GNU Linux-libre 4.19.242-gnu1
[releases.git] / drivers / tty / synclink_gt.c
1 // SPDX-License-Identifier: GPL-1.0+
2 /*
3  * Device driver for Microgate SyncLink GT serial adapters.
4  *
5  * written by Paul Fulghum for Microgate Corporation
6  * paulkf@microgate.com
7  *
8  * Microgate and SyncLink are trademarks of Microgate Corporation
9  *
10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
11  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
12  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
13  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
14  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
15  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
16  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
17  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
18  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
19  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
20  * OF THE POSSIBILITY OF SUCH DAMAGE.
21  */
22
23 /*
24  * DEBUG OUTPUT DEFINITIONS
25  *
26  * uncomment lines below to enable specific types of debug output
27  *
28  * DBGINFO   information - most verbose output
29  * DBGERR    serious errors
30  * DBGBH     bottom half service routine debugging
31  * DBGISR    interrupt service routine debugging
32  * DBGDATA   output receive and transmit data
33  * DBGTBUF   output transmit DMA buffers and registers
34  * DBGRBUF   output receive DMA buffers and registers
35  */
36
37 #define DBGINFO(fmt) if (debug_level >= DEBUG_LEVEL_INFO) printk fmt
38 #define DBGERR(fmt) if (debug_level >= DEBUG_LEVEL_ERROR) printk fmt
39 #define DBGBH(fmt) if (debug_level >= DEBUG_LEVEL_BH) printk fmt
40 #define DBGISR(fmt) if (debug_level >= DEBUG_LEVEL_ISR) printk fmt
41 #define DBGDATA(info, buf, size, label) if (debug_level >= DEBUG_LEVEL_DATA) trace_block((info), (buf), (size), (label))
42 /*#define DBGTBUF(info) dump_tbufs(info)*/
43 /*#define DBGRBUF(info) dump_rbufs(info)*/
44
45
46 #include <linux/module.h>
47 #include <linux/errno.h>
48 #include <linux/signal.h>
49 #include <linux/sched.h>
50 #include <linux/timer.h>
51 #include <linux/interrupt.h>
52 #include <linux/pci.h>
53 #include <linux/tty.h>
54 #include <linux/tty_flip.h>
55 #include <linux/serial.h>
56 #include <linux/major.h>
57 #include <linux/string.h>
58 #include <linux/fcntl.h>
59 #include <linux/ptrace.h>
60 #include <linux/ioport.h>
61 #include <linux/mm.h>
62 #include <linux/seq_file.h>
63 #include <linux/slab.h>
64 #include <linux/netdevice.h>
65 #include <linux/vmalloc.h>
66 #include <linux/init.h>
67 #include <linux/delay.h>
68 #include <linux/ioctl.h>
69 #include <linux/termios.h>
70 #include <linux/bitops.h>
71 #include <linux/workqueue.h>
72 #include <linux/hdlc.h>
73 #include <linux/synclink.h>
74
75 #include <asm/io.h>
76 #include <asm/irq.h>
77 #include <asm/dma.h>
78 #include <asm/types.h>
79 #include <linux/uaccess.h>
80
81 #if defined(CONFIG_HDLC) || (defined(CONFIG_HDLC_MODULE) && defined(CONFIG_SYNCLINK_GT_MODULE))
82 #define SYNCLINK_GENERIC_HDLC 1
83 #else
84 #define SYNCLINK_GENERIC_HDLC 0
85 #endif
86
87 /*
88  * module identification
89  */
90 static char *driver_name     = "SyncLink GT";
91 static char *slgt_driver_name = "synclink_gt";
92 static char *tty_dev_prefix  = "ttySLG";
93 MODULE_LICENSE("GPL");
94 #define MGSL_MAGIC 0x5401
95 #define MAX_DEVICES 32
96
97 static const struct pci_device_id pci_table[] = {
98         {PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
99         {PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT2_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
100         {PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT4_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
101         {PCI_VENDOR_ID_MICROGATE, SYNCLINK_AC_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
102         {0,}, /* terminate list */
103 };
104 MODULE_DEVICE_TABLE(pci, pci_table);
105
106 static int  init_one(struct pci_dev *dev,const struct pci_device_id *ent);
107 static void remove_one(struct pci_dev *dev);
108 static struct pci_driver pci_driver = {
109         .name           = "synclink_gt",
110         .id_table       = pci_table,
111         .probe          = init_one,
112         .remove         = remove_one,
113 };
114
115 static bool pci_registered;
116
117 /*
118  * module configuration and status
119  */
120 static struct slgt_info *slgt_device_list;
121 static int slgt_device_count;
122
123 static int ttymajor;
124 static int debug_level;
125 static int maxframe[MAX_DEVICES];
126
127 module_param(ttymajor, int, 0);
128 module_param(debug_level, int, 0);
129 module_param_array(maxframe, int, NULL, 0);
130
131 MODULE_PARM_DESC(ttymajor, "TTY major device number override: 0=auto assigned");
132 MODULE_PARM_DESC(debug_level, "Debug syslog output: 0=disabled, 1 to 5=increasing detail");
133 MODULE_PARM_DESC(maxframe, "Maximum frame size used by device (4096 to 65535)");
134
135 /*
136  * tty support and callbacks
137  */
138 static struct tty_driver *serial_driver;
139
140 static void wait_until_sent(struct tty_struct *tty, int timeout);
141 static void flush_buffer(struct tty_struct *tty);
142 static void tx_release(struct tty_struct *tty);
143
144 /*
145  * generic HDLC support
146  */
147 #define dev_to_port(D) (dev_to_hdlc(D)->priv)
148
149
150 /*
151  * device specific structures, macros and functions
152  */
153
154 #define SLGT_MAX_PORTS 4
155 #define SLGT_REG_SIZE  256
156
157 /*
158  * conditional wait facility
159  */
160 struct cond_wait {
161         struct cond_wait *next;
162         wait_queue_head_t q;
163         wait_queue_entry_t wait;
164         unsigned int data;
165 };
166 static void flush_cond_wait(struct cond_wait **head);
167
168 /*
169  * DMA buffer descriptor and access macros
170  */
171 struct slgt_desc
172 {
173         __le16 count;
174         __le16 status;
175         __le32 pbuf;  /* physical address of data buffer */
176         __le32 next;  /* physical address of next descriptor */
177
178         /* driver book keeping */
179         char *buf;          /* virtual  address of data buffer */
180         unsigned int pdesc; /* physical address of this descriptor */
181         dma_addr_t buf_dma_addr;
182         unsigned short buf_count;
183 };
184
185 #define set_desc_buffer(a,b) (a).pbuf = cpu_to_le32((unsigned int)(b))
186 #define set_desc_next(a,b) (a).next   = cpu_to_le32((unsigned int)(b))
187 #define set_desc_count(a,b)(a).count  = cpu_to_le16((unsigned short)(b))
188 #define set_desc_eof(a,b)  (a).status = cpu_to_le16((b) ? (le16_to_cpu((a).status) | BIT0) : (le16_to_cpu((a).status) & ~BIT0))
189 #define set_desc_status(a, b) (a).status = cpu_to_le16((unsigned short)(b))
190 #define desc_count(a)      (le16_to_cpu((a).count))
191 #define desc_status(a)     (le16_to_cpu((a).status))
192 #define desc_complete(a)   (le16_to_cpu((a).status) & BIT15)
193 #define desc_eof(a)        (le16_to_cpu((a).status) & BIT2)
194 #define desc_crc_error(a)  (le16_to_cpu((a).status) & BIT1)
195 #define desc_abort(a)      (le16_to_cpu((a).status) & BIT0)
196 #define desc_residue(a)    ((le16_to_cpu((a).status) & 0x38) >> 3)
197
198 struct _input_signal_events {
199         int ri_up;
200         int ri_down;
201         int dsr_up;
202         int dsr_down;
203         int dcd_up;
204         int dcd_down;
205         int cts_up;
206         int cts_down;
207 };
208
209 /*
210  * device instance data structure
211  */
212 struct slgt_info {
213         void *if_ptr;           /* General purpose pointer (used by SPPP) */
214         struct tty_port port;
215
216         struct slgt_info *next_device;  /* device list link */
217
218         int magic;
219
220         char device_name[25];
221         struct pci_dev *pdev;
222
223         int port_count;  /* count of ports on adapter */
224         int adapter_num; /* adapter instance number */
225         int port_num;    /* port instance number */
226
227         /* array of pointers to port contexts on this adapter */
228         struct slgt_info *port_array[SLGT_MAX_PORTS];
229
230         int                     line;           /* tty line instance number */
231
232         struct mgsl_icount      icount;
233
234         int                     timeout;
235         int                     x_char;         /* xon/xoff character */
236         unsigned int            read_status_mask;
237         unsigned int            ignore_status_mask;
238
239         wait_queue_head_t       status_event_wait_q;
240         wait_queue_head_t       event_wait_q;
241         struct timer_list       tx_timer;
242         struct timer_list       rx_timer;
243
244         unsigned int            gpio_present;
245         struct cond_wait        *gpio_wait_q;
246
247         spinlock_t lock;        /* spinlock for synchronizing with ISR */
248
249         struct work_struct task;
250         u32 pending_bh;
251         bool bh_requested;
252         bool bh_running;
253
254         int isr_overflow;
255         bool irq_requested;     /* true if IRQ requested */
256         bool irq_occurred;      /* for diagnostics use */
257
258         /* device configuration */
259
260         unsigned int bus_type;
261         unsigned int irq_level;
262         unsigned long irq_flags;
263
264         unsigned char __iomem * reg_addr;  /* memory mapped registers address */
265         u32 phys_reg_addr;
266         bool reg_addr_requested;
267
268         MGSL_PARAMS params;       /* communications parameters */
269         u32 idle_mode;
270         u32 max_frame_size;       /* as set by device config */
271
272         unsigned int rbuf_fill_level;
273         unsigned int rx_pio;
274         unsigned int if_mode;
275         unsigned int base_clock;
276         unsigned int xsync;
277         unsigned int xctrl;
278
279         /* device status */
280
281         bool rx_enabled;
282         bool rx_restart;
283
284         bool tx_enabled;
285         bool tx_active;
286
287         unsigned char signals;    /* serial signal states */
288         int init_error;  /* initialization error */
289
290         unsigned char *tx_buf;
291         int tx_count;
292
293         char *flag_buf;
294         bool drop_rts_on_tx_done;
295         struct  _input_signal_events    input_signal_events;
296
297         int dcd_chkcount;       /* check counts to prevent */
298         int cts_chkcount;       /* too many IRQs if a signal */
299         int dsr_chkcount;       /* is floating */
300         int ri_chkcount;
301
302         char *bufs;             /* virtual address of DMA buffer lists */
303         dma_addr_t bufs_dma_addr; /* physical address of buffer descriptors */
304
305         unsigned int rbuf_count;
306         struct slgt_desc *rbufs;
307         unsigned int rbuf_current;
308         unsigned int rbuf_index;
309         unsigned int rbuf_fill_index;
310         unsigned short rbuf_fill_count;
311
312         unsigned int tbuf_count;
313         struct slgt_desc *tbufs;
314         unsigned int tbuf_current;
315         unsigned int tbuf_start;
316
317         unsigned char *tmp_rbuf;
318         unsigned int tmp_rbuf_count;
319
320         /* SPPP/Cisco HDLC device parts */
321
322         int netcount;
323         spinlock_t netlock;
324 #if SYNCLINK_GENERIC_HDLC
325         struct net_device *netdev;
326 #endif
327
328 };
329
330 static MGSL_PARAMS default_params = {
331         .mode            = MGSL_MODE_HDLC,
332         .loopback        = 0,
333         .flags           = HDLC_FLAG_UNDERRUN_ABORT15,
334         .encoding        = HDLC_ENCODING_NRZI_SPACE,
335         .clock_speed     = 0,
336         .addr_filter     = 0xff,
337         .crc_type        = HDLC_CRC_16_CCITT,
338         .preamble_length = HDLC_PREAMBLE_LENGTH_8BITS,
339         .preamble        = HDLC_PREAMBLE_PATTERN_NONE,
340         .data_rate       = 9600,
341         .data_bits       = 8,
342         .stop_bits       = 1,
343         .parity          = ASYNC_PARITY_NONE
344 };
345
346
347 #define BH_RECEIVE  1
348 #define BH_TRANSMIT 2
349 #define BH_STATUS   4
350 #define IO_PIN_SHUTDOWN_LIMIT 100
351
352 #define DMABUFSIZE 256
353 #define DESC_LIST_SIZE 4096
354
355 #define MASK_PARITY  BIT1
356 #define MASK_FRAMING BIT0
357 #define MASK_BREAK   BIT14
358 #define MASK_OVERRUN BIT4
359
360 #define GSR   0x00 /* global status */
361 #define JCR   0x04 /* JTAG control */
362 #define IODR  0x08 /* GPIO direction */
363 #define IOER  0x0c /* GPIO interrupt enable */
364 #define IOVR  0x10 /* GPIO value */
365 #define IOSR  0x14 /* GPIO interrupt status */
366 #define TDR   0x80 /* tx data */
367 #define RDR   0x80 /* rx data */
368 #define TCR   0x82 /* tx control */
369 #define TIR   0x84 /* tx idle */
370 #define TPR   0x85 /* tx preamble */
371 #define RCR   0x86 /* rx control */
372 #define VCR   0x88 /* V.24 control */
373 #define CCR   0x89 /* clock control */
374 #define BDR   0x8a /* baud divisor */
375 #define SCR   0x8c /* serial control */
376 #define SSR   0x8e /* serial status */
377 #define RDCSR 0x90 /* rx DMA control/status */
378 #define TDCSR 0x94 /* tx DMA control/status */
379 #define RDDAR 0x98 /* rx DMA descriptor address */
380 #define TDDAR 0x9c /* tx DMA descriptor address */
381 #define XSR   0x40 /* extended sync pattern */
382 #define XCR   0x44 /* extended control */
383
384 #define RXIDLE      BIT14
385 #define RXBREAK     BIT14
386 #define IRQ_TXDATA  BIT13
387 #define IRQ_TXIDLE  BIT12
388 #define IRQ_TXUNDER BIT11 /* HDLC */
389 #define IRQ_RXDATA  BIT10
390 #define IRQ_RXIDLE  BIT9  /* HDLC */
391 #define IRQ_RXBREAK BIT9  /* async */
392 #define IRQ_RXOVER  BIT8
393 #define IRQ_DSR     BIT7
394 #define IRQ_CTS     BIT6
395 #define IRQ_DCD     BIT5
396 #define IRQ_RI      BIT4
397 #define IRQ_ALL     0x3ff0
398 #define IRQ_MASTER  BIT0
399
400 #define slgt_irq_on(info, mask) \
401         wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) | (mask)))
402 #define slgt_irq_off(info, mask) \
403         wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) & ~(mask)))
404
405 static __u8  rd_reg8(struct slgt_info *info, unsigned int addr);
406 static void  wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value);
407 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr);
408 static void  wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value);
409 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr);
410 static void  wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value);
411
412 static void  msc_set_vcr(struct slgt_info *info);
413
414 static int  startup(struct slgt_info *info);
415 static int  block_til_ready(struct tty_struct *tty, struct file * filp,struct slgt_info *info);
416 static void shutdown(struct slgt_info *info);
417 static void program_hw(struct slgt_info *info);
418 static void change_params(struct slgt_info *info);
419
420 static int  adapter_test(struct slgt_info *info);
421
422 static void reset_port(struct slgt_info *info);
423 static void async_mode(struct slgt_info *info);
424 static void sync_mode(struct slgt_info *info);
425
426 static void rx_stop(struct slgt_info *info);
427 static void rx_start(struct slgt_info *info);
428 static void reset_rbufs(struct slgt_info *info);
429 static void free_rbufs(struct slgt_info *info, unsigned int first, unsigned int last);
430 static bool rx_get_frame(struct slgt_info *info);
431 static bool rx_get_buf(struct slgt_info *info);
432
433 static void tx_start(struct slgt_info *info);
434 static void tx_stop(struct slgt_info *info);
435 static void tx_set_idle(struct slgt_info *info);
436 static unsigned int tbuf_bytes(struct slgt_info *info);
437 static void reset_tbufs(struct slgt_info *info);
438 static void tdma_reset(struct slgt_info *info);
439 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int count);
440
441 static void get_gtsignals(struct slgt_info *info);
442 static void set_gtsignals(struct slgt_info *info);
443 static void set_rate(struct slgt_info *info, u32 data_rate);
444
445 static void bh_transmit(struct slgt_info *info);
446 static void isr_txeom(struct slgt_info *info, unsigned short status);
447
448 static void tx_timeout(struct timer_list *t);
449 static void rx_timeout(struct timer_list *t);
450
451 /*
452  * ioctl handlers
453  */
454 static int  get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount);
455 static int  get_params(struct slgt_info *info, MGSL_PARAMS __user *params);
456 static int  set_params(struct slgt_info *info, MGSL_PARAMS __user *params);
457 static int  get_txidle(struct slgt_info *info, int __user *idle_mode);
458 static int  set_txidle(struct slgt_info *info, int idle_mode);
459 static int  tx_enable(struct slgt_info *info, int enable);
460 static int  tx_abort(struct slgt_info *info);
461 static int  rx_enable(struct slgt_info *info, int enable);
462 static int  modem_input_wait(struct slgt_info *info,int arg);
463 static int  wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr);
464 static int  get_interface(struct slgt_info *info, int __user *if_mode);
465 static int  set_interface(struct slgt_info *info, int if_mode);
466 static int  set_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
467 static int  get_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
468 static int  wait_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
469 static int  get_xsync(struct slgt_info *info, int __user *if_mode);
470 static int  set_xsync(struct slgt_info *info, int if_mode);
471 static int  get_xctrl(struct slgt_info *info, int __user *if_mode);
472 static int  set_xctrl(struct slgt_info *info, int if_mode);
473
474 /*
475  * driver functions
476  */
477 static void release_resources(struct slgt_info *info);
478
479 /*
480  * DEBUG OUTPUT CODE
481  */
482 #ifndef DBGINFO
483 #define DBGINFO(fmt)
484 #endif
485 #ifndef DBGERR
486 #define DBGERR(fmt)
487 #endif
488 #ifndef DBGBH
489 #define DBGBH(fmt)
490 #endif
491 #ifndef DBGISR
492 #define DBGISR(fmt)
493 #endif
494
495 #ifdef DBGDATA
496 static void trace_block(struct slgt_info *info, const char *data, int count, const char *label)
497 {
498         int i;
499         int linecount;
500         printk("%s %s data:\n",info->device_name, label);
501         while(count) {
502                 linecount = (count > 16) ? 16 : count;
503                 for(i=0; i < linecount; i++)
504                         printk("%02X ",(unsigned char)data[i]);
505                 for(;i<17;i++)
506                         printk("   ");
507                 for(i=0;i<linecount;i++) {
508                         if (data[i]>=040 && data[i]<=0176)
509                                 printk("%c",data[i]);
510                         else
511                                 printk(".");
512                 }
513                 printk("\n");
514                 data  += linecount;
515                 count -= linecount;
516         }
517 }
518 #else
519 #define DBGDATA(info, buf, size, label)
520 #endif
521
522 #ifdef DBGTBUF
523 static void dump_tbufs(struct slgt_info *info)
524 {
525         int i;
526         printk("tbuf_current=%d\n", info->tbuf_current);
527         for (i=0 ; i < info->tbuf_count ; i++) {
528                 printk("%d: count=%04X status=%04X\n",
529                         i, le16_to_cpu(info->tbufs[i].count), le16_to_cpu(info->tbufs[i].status));
530         }
531 }
532 #else
533 #define DBGTBUF(info)
534 #endif
535
536 #ifdef DBGRBUF
537 static void dump_rbufs(struct slgt_info *info)
538 {
539         int i;
540         printk("rbuf_current=%d\n", info->rbuf_current);
541         for (i=0 ; i < info->rbuf_count ; i++) {
542                 printk("%d: count=%04X status=%04X\n",
543                         i, le16_to_cpu(info->rbufs[i].count), le16_to_cpu(info->rbufs[i].status));
544         }
545 }
546 #else
547 #define DBGRBUF(info)
548 #endif
549
550 static inline int sanity_check(struct slgt_info *info, char *devname, const char *name)
551 {
552 #ifdef SANITY_CHECK
553         if (!info) {
554                 printk("null struct slgt_info for (%s) in %s\n", devname, name);
555                 return 1;
556         }
557         if (info->magic != MGSL_MAGIC) {
558                 printk("bad magic number struct slgt_info (%s) in %s\n", devname, name);
559                 return 1;
560         }
561 #else
562         if (!info)
563                 return 1;
564 #endif
565         return 0;
566 }
567
568 /**
569  * line discipline callback wrappers
570  *
571  * The wrappers maintain line discipline references
572  * while calling into the line discipline.
573  *
574  * ldisc_receive_buf  - pass receive data to line discipline
575  */
576 static void ldisc_receive_buf(struct tty_struct *tty,
577                               const __u8 *data, char *flags, int count)
578 {
579         struct tty_ldisc *ld;
580         if (!tty)
581                 return;
582         ld = tty_ldisc_ref(tty);
583         if (ld) {
584                 if (ld->ops->receive_buf)
585                         ld->ops->receive_buf(tty, data, flags, count);
586                 tty_ldisc_deref(ld);
587         }
588 }
589
590 /* tty callbacks */
591
592 static int open(struct tty_struct *tty, struct file *filp)
593 {
594         struct slgt_info *info;
595         int retval, line;
596         unsigned long flags;
597
598         line = tty->index;
599         if (line >= slgt_device_count) {
600                 DBGERR(("%s: open with invalid line #%d.\n", driver_name, line));
601                 return -ENODEV;
602         }
603
604         info = slgt_device_list;
605         while(info && info->line != line)
606                 info = info->next_device;
607         if (sanity_check(info, tty->name, "open"))
608                 return -ENODEV;
609         if (info->init_error) {
610                 DBGERR(("%s init error=%d\n", info->device_name, info->init_error));
611                 return -ENODEV;
612         }
613
614         tty->driver_data = info;
615         info->port.tty = tty;
616
617         DBGINFO(("%s open, old ref count = %d\n", info->device_name, info->port.count));
618
619         mutex_lock(&info->port.mutex);
620         info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
621
622         spin_lock_irqsave(&info->netlock, flags);
623         if (info->netcount) {
624                 retval = -EBUSY;
625                 spin_unlock_irqrestore(&info->netlock, flags);
626                 mutex_unlock(&info->port.mutex);
627                 goto cleanup;
628         }
629         info->port.count++;
630         spin_unlock_irqrestore(&info->netlock, flags);
631
632         if (info->port.count == 1) {
633                 /* 1st open on this device, init hardware */
634                 retval = startup(info);
635                 if (retval < 0) {
636                         mutex_unlock(&info->port.mutex);
637                         goto cleanup;
638                 }
639         }
640         mutex_unlock(&info->port.mutex);
641         retval = block_til_ready(tty, filp, info);
642         if (retval) {
643                 DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval));
644                 goto cleanup;
645         }
646
647         retval = 0;
648
649 cleanup:
650         if (retval) {
651                 if (tty->count == 1)
652                         info->port.tty = NULL; /* tty layer will release tty struct */
653                 if(info->port.count)
654                         info->port.count--;
655         }
656
657         DBGINFO(("%s open rc=%d\n", info->device_name, retval));
658         return retval;
659 }
660
661 static void close(struct tty_struct *tty, struct file *filp)
662 {
663         struct slgt_info *info = tty->driver_data;
664
665         if (sanity_check(info, tty->name, "close"))
666                 return;
667         DBGINFO(("%s close entry, count=%d\n", info->device_name, info->port.count));
668
669         if (tty_port_close_start(&info->port, tty, filp) == 0)
670                 goto cleanup;
671
672         mutex_lock(&info->port.mutex);
673         if (tty_port_initialized(&info->port))
674                 wait_until_sent(tty, info->timeout);
675         flush_buffer(tty);
676         tty_ldisc_flush(tty);
677
678         shutdown(info);
679         mutex_unlock(&info->port.mutex);
680
681         tty_port_close_end(&info->port, tty);
682         info->port.tty = NULL;
683 cleanup:
684         DBGINFO(("%s close exit, count=%d\n", tty->driver->name, info->port.count));
685 }
686
687 static void hangup(struct tty_struct *tty)
688 {
689         struct slgt_info *info = tty->driver_data;
690         unsigned long flags;
691
692         if (sanity_check(info, tty->name, "hangup"))
693                 return;
694         DBGINFO(("%s hangup\n", info->device_name));
695
696         flush_buffer(tty);
697
698         mutex_lock(&info->port.mutex);
699         shutdown(info);
700
701         spin_lock_irqsave(&info->port.lock, flags);
702         info->port.count = 0;
703         info->port.tty = NULL;
704         spin_unlock_irqrestore(&info->port.lock, flags);
705         tty_port_set_active(&info->port, 0);
706         mutex_unlock(&info->port.mutex);
707
708         wake_up_interruptible(&info->port.open_wait);
709 }
710
711 static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
712 {
713         struct slgt_info *info = tty->driver_data;
714         unsigned long flags;
715
716         DBGINFO(("%s set_termios\n", tty->driver->name));
717
718         change_params(info);
719
720         /* Handle transition to B0 status */
721         if ((old_termios->c_cflag & CBAUD) && !C_BAUD(tty)) {
722                 info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
723                 spin_lock_irqsave(&info->lock,flags);
724                 set_gtsignals(info);
725                 spin_unlock_irqrestore(&info->lock,flags);
726         }
727
728         /* Handle transition away from B0 status */
729         if (!(old_termios->c_cflag & CBAUD) && C_BAUD(tty)) {
730                 info->signals |= SerialSignal_DTR;
731                 if (!C_CRTSCTS(tty) || !tty_throttled(tty))
732                         info->signals |= SerialSignal_RTS;
733                 spin_lock_irqsave(&info->lock,flags);
734                 set_gtsignals(info);
735                 spin_unlock_irqrestore(&info->lock,flags);
736         }
737
738         /* Handle turning off CRTSCTS */
739         if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
740                 tty->hw_stopped = 0;
741                 tx_release(tty);
742         }
743 }
744
745 static void update_tx_timer(struct slgt_info *info)
746 {
747         /*
748          * use worst case speed of 1200bps to calculate transmit timeout
749          * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
750          */
751         if (info->params.mode == MGSL_MODE_HDLC) {
752                 int timeout  = (tbuf_bytes(info) * 7) + 1000;
753                 mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
754         }
755 }
756
757 static int write(struct tty_struct *tty,
758                  const unsigned char *buf, int count)
759 {
760         int ret = 0;
761         struct slgt_info *info = tty->driver_data;
762         unsigned long flags;
763
764         if (sanity_check(info, tty->name, "write"))
765                 return -EIO;
766
767         DBGINFO(("%s write count=%d\n", info->device_name, count));
768
769         if (!info->tx_buf || (count > info->max_frame_size))
770                 return -EIO;
771
772         if (!count || tty->stopped || tty->hw_stopped)
773                 return 0;
774
775         spin_lock_irqsave(&info->lock, flags);
776
777         if (info->tx_count) {
778                 /* send accumulated data from send_char() */
779                 if (!tx_load(info, info->tx_buf, info->tx_count))
780                         goto cleanup;
781                 info->tx_count = 0;
782         }
783
784         if (tx_load(info, buf, count))
785                 ret = count;
786
787 cleanup:
788         spin_unlock_irqrestore(&info->lock, flags);
789         DBGINFO(("%s write rc=%d\n", info->device_name, ret));
790         return ret;
791 }
792
793 static int put_char(struct tty_struct *tty, unsigned char ch)
794 {
795         struct slgt_info *info = tty->driver_data;
796         unsigned long flags;
797         int ret = 0;
798
799         if (sanity_check(info, tty->name, "put_char"))
800                 return 0;
801         DBGINFO(("%s put_char(%d)\n", info->device_name, ch));
802         if (!info->tx_buf)
803                 return 0;
804         spin_lock_irqsave(&info->lock,flags);
805         if (info->tx_count < info->max_frame_size) {
806                 info->tx_buf[info->tx_count++] = ch;
807                 ret = 1;
808         }
809         spin_unlock_irqrestore(&info->lock,flags);
810         return ret;
811 }
812
813 static void send_xchar(struct tty_struct *tty, char ch)
814 {
815         struct slgt_info *info = tty->driver_data;
816         unsigned long flags;
817
818         if (sanity_check(info, tty->name, "send_xchar"))
819                 return;
820         DBGINFO(("%s send_xchar(%d)\n", info->device_name, ch));
821         info->x_char = ch;
822         if (ch) {
823                 spin_lock_irqsave(&info->lock,flags);
824                 if (!info->tx_enabled)
825                         tx_start(info);
826                 spin_unlock_irqrestore(&info->lock,flags);
827         }
828 }
829
830 static void wait_until_sent(struct tty_struct *tty, int timeout)
831 {
832         struct slgt_info *info = tty->driver_data;
833         unsigned long orig_jiffies, char_time;
834
835         if (!info )
836                 return;
837         if (sanity_check(info, tty->name, "wait_until_sent"))
838                 return;
839         DBGINFO(("%s wait_until_sent entry\n", info->device_name));
840         if (!tty_port_initialized(&info->port))
841                 goto exit;
842
843         orig_jiffies = jiffies;
844
845         /* Set check interval to 1/5 of estimated time to
846          * send a character, and make it at least 1. The check
847          * interval should also be less than the timeout.
848          * Note: use tight timings here to satisfy the NIST-PCTS.
849          */
850
851         if (info->params.data_rate) {
852                 char_time = info->timeout/(32 * 5);
853                 if (!char_time)
854                         char_time++;
855         } else
856                 char_time = 1;
857
858         if (timeout)
859                 char_time = min_t(unsigned long, char_time, timeout);
860
861         while (info->tx_active) {
862                 msleep_interruptible(jiffies_to_msecs(char_time));
863                 if (signal_pending(current))
864                         break;
865                 if (timeout && time_after(jiffies, orig_jiffies + timeout))
866                         break;
867         }
868 exit:
869         DBGINFO(("%s wait_until_sent exit\n", info->device_name));
870 }
871
872 static int write_room(struct tty_struct *tty)
873 {
874         struct slgt_info *info = tty->driver_data;
875         int ret;
876
877         if (sanity_check(info, tty->name, "write_room"))
878                 return 0;
879         ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
880         DBGINFO(("%s write_room=%d\n", info->device_name, ret));
881         return ret;
882 }
883
884 static void flush_chars(struct tty_struct *tty)
885 {
886         struct slgt_info *info = tty->driver_data;
887         unsigned long flags;
888
889         if (sanity_check(info, tty->name, "flush_chars"))
890                 return;
891         DBGINFO(("%s flush_chars entry tx_count=%d\n", info->device_name, info->tx_count));
892
893         if (info->tx_count <= 0 || tty->stopped ||
894             tty->hw_stopped || !info->tx_buf)
895                 return;
896
897         DBGINFO(("%s flush_chars start transmit\n", info->device_name));
898
899         spin_lock_irqsave(&info->lock,flags);
900         if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
901                 info->tx_count = 0;
902         spin_unlock_irqrestore(&info->lock,flags);
903 }
904
905 static void flush_buffer(struct tty_struct *tty)
906 {
907         struct slgt_info *info = tty->driver_data;
908         unsigned long flags;
909
910         if (sanity_check(info, tty->name, "flush_buffer"))
911                 return;
912         DBGINFO(("%s flush_buffer\n", info->device_name));
913
914         spin_lock_irqsave(&info->lock, flags);
915         info->tx_count = 0;
916         spin_unlock_irqrestore(&info->lock, flags);
917
918         tty_wakeup(tty);
919 }
920
921 /*
922  * throttle (stop) transmitter
923  */
924 static void tx_hold(struct tty_struct *tty)
925 {
926         struct slgt_info *info = tty->driver_data;
927         unsigned long flags;
928
929         if (sanity_check(info, tty->name, "tx_hold"))
930                 return;
931         DBGINFO(("%s tx_hold\n", info->device_name));
932         spin_lock_irqsave(&info->lock,flags);
933         if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
934                 tx_stop(info);
935         spin_unlock_irqrestore(&info->lock,flags);
936 }
937
938 /*
939  * release (start) transmitter
940  */
941 static void tx_release(struct tty_struct *tty)
942 {
943         struct slgt_info *info = tty->driver_data;
944         unsigned long flags;
945
946         if (sanity_check(info, tty->name, "tx_release"))
947                 return;
948         DBGINFO(("%s tx_release\n", info->device_name));
949         spin_lock_irqsave(&info->lock, flags);
950         if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
951                 info->tx_count = 0;
952         spin_unlock_irqrestore(&info->lock, flags);
953 }
954
955 /*
956  * Service an IOCTL request
957  *
958  * Arguments
959  *
960  *      tty     pointer to tty instance data
961  *      cmd     IOCTL command code
962  *      arg     command argument/context
963  *
964  * Return 0 if success, otherwise error code
965  */
966 static int ioctl(struct tty_struct *tty,
967                  unsigned int cmd, unsigned long arg)
968 {
969         struct slgt_info *info = tty->driver_data;
970         void __user *argp = (void __user *)arg;
971         int ret;
972
973         if (sanity_check(info, tty->name, "ioctl"))
974                 return -ENODEV;
975         DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
976
977         if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
978             (cmd != TIOCMIWAIT)) {
979                 if (tty_io_error(tty))
980                     return -EIO;
981         }
982
983         switch (cmd) {
984         case MGSL_IOCWAITEVENT:
985                 return wait_mgsl_event(info, argp);
986         case TIOCMIWAIT:
987                 return modem_input_wait(info,(int)arg);
988         case MGSL_IOCSGPIO:
989                 return set_gpio(info, argp);
990         case MGSL_IOCGGPIO:
991                 return get_gpio(info, argp);
992         case MGSL_IOCWAITGPIO:
993                 return wait_gpio(info, argp);
994         case MGSL_IOCGXSYNC:
995                 return get_xsync(info, argp);
996         case MGSL_IOCSXSYNC:
997                 return set_xsync(info, (int)arg);
998         case MGSL_IOCGXCTRL:
999                 return get_xctrl(info, argp);
1000         case MGSL_IOCSXCTRL:
1001                 return set_xctrl(info, (int)arg);
1002         }
1003         mutex_lock(&info->port.mutex);
1004         switch (cmd) {
1005         case MGSL_IOCGPARAMS:
1006                 ret = get_params(info, argp);
1007                 break;
1008         case MGSL_IOCSPARAMS:
1009                 ret = set_params(info, argp);
1010                 break;
1011         case MGSL_IOCGTXIDLE:
1012                 ret = get_txidle(info, argp);
1013                 break;
1014         case MGSL_IOCSTXIDLE:
1015                 ret = set_txidle(info, (int)arg);
1016                 break;
1017         case MGSL_IOCTXENABLE:
1018                 ret = tx_enable(info, (int)arg);
1019                 break;
1020         case MGSL_IOCRXENABLE:
1021                 ret = rx_enable(info, (int)arg);
1022                 break;
1023         case MGSL_IOCTXABORT:
1024                 ret = tx_abort(info);
1025                 break;
1026         case MGSL_IOCGSTATS:
1027                 ret = get_stats(info, argp);
1028                 break;
1029         case MGSL_IOCGIF:
1030                 ret = get_interface(info, argp);
1031                 break;
1032         case MGSL_IOCSIF:
1033                 ret = set_interface(info,(int)arg);
1034                 break;
1035         default:
1036                 ret = -ENOIOCTLCMD;
1037         }
1038         mutex_unlock(&info->port.mutex);
1039         return ret;
1040 }
1041
1042 static int get_icount(struct tty_struct *tty,
1043                                 struct serial_icounter_struct *icount)
1044
1045 {
1046         struct slgt_info *info = tty->driver_data;
1047         struct mgsl_icount cnow;        /* kernel counter temps */
1048         unsigned long flags;
1049
1050         spin_lock_irqsave(&info->lock,flags);
1051         cnow = info->icount;
1052         spin_unlock_irqrestore(&info->lock,flags);
1053
1054         icount->cts = cnow.cts;
1055         icount->dsr = cnow.dsr;
1056         icount->rng = cnow.rng;
1057         icount->dcd = cnow.dcd;
1058         icount->rx = cnow.rx;
1059         icount->tx = cnow.tx;
1060         icount->frame = cnow.frame;
1061         icount->overrun = cnow.overrun;
1062         icount->parity = cnow.parity;
1063         icount->brk = cnow.brk;
1064         icount->buf_overrun = cnow.buf_overrun;
1065
1066         return 0;
1067 }
1068
1069 /*
1070  * support for 32 bit ioctl calls on 64 bit systems
1071  */
1072 #ifdef CONFIG_COMPAT
1073 static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
1074 {
1075         struct MGSL_PARAMS32 tmp_params;
1076
1077         DBGINFO(("%s get_params32\n", info->device_name));
1078         memset(&tmp_params, 0, sizeof(tmp_params));
1079         tmp_params.mode            = (compat_ulong_t)info->params.mode;
1080         tmp_params.loopback        = info->params.loopback;
1081         tmp_params.flags           = info->params.flags;
1082         tmp_params.encoding        = info->params.encoding;
1083         tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
1084         tmp_params.addr_filter     = info->params.addr_filter;
1085         tmp_params.crc_type        = info->params.crc_type;
1086         tmp_params.preamble_length = info->params.preamble_length;
1087         tmp_params.preamble        = info->params.preamble;
1088         tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
1089         tmp_params.data_bits       = info->params.data_bits;
1090         tmp_params.stop_bits       = info->params.stop_bits;
1091         tmp_params.parity          = info->params.parity;
1092         if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
1093                 return -EFAULT;
1094         return 0;
1095 }
1096
1097 static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
1098 {
1099         struct MGSL_PARAMS32 tmp_params;
1100
1101         DBGINFO(("%s set_params32\n", info->device_name));
1102         if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
1103                 return -EFAULT;
1104
1105         spin_lock(&info->lock);
1106         if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
1107                 info->base_clock = tmp_params.clock_speed;
1108         } else {
1109                 info->params.mode            = tmp_params.mode;
1110                 info->params.loopback        = tmp_params.loopback;
1111                 info->params.flags           = tmp_params.flags;
1112                 info->params.encoding        = tmp_params.encoding;
1113                 info->params.clock_speed     = tmp_params.clock_speed;
1114                 info->params.addr_filter     = tmp_params.addr_filter;
1115                 info->params.crc_type        = tmp_params.crc_type;
1116                 info->params.preamble_length = tmp_params.preamble_length;
1117                 info->params.preamble        = tmp_params.preamble;
1118                 info->params.data_rate       = tmp_params.data_rate;
1119                 info->params.data_bits       = tmp_params.data_bits;
1120                 info->params.stop_bits       = tmp_params.stop_bits;
1121                 info->params.parity          = tmp_params.parity;
1122         }
1123         spin_unlock(&info->lock);
1124
1125         program_hw(info);
1126
1127         return 0;
1128 }
1129
1130 static long slgt_compat_ioctl(struct tty_struct *tty,
1131                          unsigned int cmd, unsigned long arg)
1132 {
1133         struct slgt_info *info = tty->driver_data;
1134         int rc;
1135
1136         if (sanity_check(info, tty->name, "compat_ioctl"))
1137                 return -ENODEV;
1138         DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));
1139
1140         switch (cmd) {
1141         case MGSL_IOCSPARAMS32:
1142                 rc = set_params32(info, compat_ptr(arg));
1143                 break;
1144
1145         case MGSL_IOCGPARAMS32:
1146                 rc = get_params32(info, compat_ptr(arg));
1147                 break;
1148
1149         case MGSL_IOCGPARAMS:
1150         case MGSL_IOCSPARAMS:
1151         case MGSL_IOCGTXIDLE:
1152         case MGSL_IOCGSTATS:
1153         case MGSL_IOCWAITEVENT:
1154         case MGSL_IOCGIF:
1155         case MGSL_IOCSGPIO:
1156         case MGSL_IOCGGPIO:
1157         case MGSL_IOCWAITGPIO:
1158         case MGSL_IOCGXSYNC:
1159         case MGSL_IOCGXCTRL:
1160                 rc = ioctl(tty, cmd, (unsigned long)compat_ptr(arg));
1161                 break;
1162         default:
1163                 rc = ioctl(tty, cmd, arg);
1164         }
1165         DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
1166         return rc;
1167 }
1168 #else
1169 #define slgt_compat_ioctl NULL
1170 #endif /* ifdef CONFIG_COMPAT */
1171
1172 /*
1173  * proc fs support
1174  */
1175 static inline void line_info(struct seq_file *m, struct slgt_info *info)
1176 {
1177         char stat_buf[30];
1178         unsigned long flags;
1179
1180         seq_printf(m, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
1181                       info->device_name, info->phys_reg_addr,
1182                       info->irq_level, info->max_frame_size);
1183
1184         /* output current serial signal states */
1185         spin_lock_irqsave(&info->lock,flags);
1186         get_gtsignals(info);
1187         spin_unlock_irqrestore(&info->lock,flags);
1188
1189         stat_buf[0] = 0;
1190         stat_buf[1] = 0;
1191         if (info->signals & SerialSignal_RTS)
1192                 strcat(stat_buf, "|RTS");
1193         if (info->signals & SerialSignal_CTS)
1194                 strcat(stat_buf, "|CTS");
1195         if (info->signals & SerialSignal_DTR)
1196                 strcat(stat_buf, "|DTR");
1197         if (info->signals & SerialSignal_DSR)
1198                 strcat(stat_buf, "|DSR");
1199         if (info->signals & SerialSignal_DCD)
1200                 strcat(stat_buf, "|CD");
1201         if (info->signals & SerialSignal_RI)
1202                 strcat(stat_buf, "|RI");
1203
1204         if (info->params.mode != MGSL_MODE_ASYNC) {
1205                 seq_printf(m, "\tHDLC txok:%d rxok:%d",
1206                                info->icount.txok, info->icount.rxok);
1207                 if (info->icount.txunder)
1208                         seq_printf(m, " txunder:%d", info->icount.txunder);
1209                 if (info->icount.txabort)
1210                         seq_printf(m, " txabort:%d", info->icount.txabort);
1211                 if (info->icount.rxshort)
1212                         seq_printf(m, " rxshort:%d", info->icount.rxshort);
1213                 if (info->icount.rxlong)
1214                         seq_printf(m, " rxlong:%d", info->icount.rxlong);
1215                 if (info->icount.rxover)
1216                         seq_printf(m, " rxover:%d", info->icount.rxover);
1217                 if (info->icount.rxcrc)
1218                         seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
1219         } else {
1220                 seq_printf(m, "\tASYNC tx:%d rx:%d",
1221                                info->icount.tx, info->icount.rx);
1222                 if (info->icount.frame)
1223                         seq_printf(m, " fe:%d", info->icount.frame);
1224                 if (info->icount.parity)
1225                         seq_printf(m, " pe:%d", info->icount.parity);
1226                 if (info->icount.brk)
1227                         seq_printf(m, " brk:%d", info->icount.brk);
1228                 if (info->icount.overrun)
1229                         seq_printf(m, " oe:%d", info->icount.overrun);
1230         }
1231
1232         /* Append serial signal status to end */
1233         seq_printf(m, " %s\n", stat_buf+1);
1234
1235         seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
1236                        info->tx_active,info->bh_requested,info->bh_running,
1237                        info->pending_bh);
1238 }
1239
1240 /* Called to print information about devices
1241  */
1242 static int synclink_gt_proc_show(struct seq_file *m, void *v)
1243 {
1244         struct slgt_info *info;
1245
1246         seq_puts(m, "synclink_gt driver\n");
1247
1248         info = slgt_device_list;
1249         while( info ) {
1250                 line_info(m, info);
1251                 info = info->next_device;
1252         }
1253         return 0;
1254 }
1255
1256 /*
1257  * return count of bytes in transmit buffer
1258  */
1259 static int chars_in_buffer(struct tty_struct *tty)
1260 {
1261         struct slgt_info *info = tty->driver_data;
1262         int count;
1263         if (sanity_check(info, tty->name, "chars_in_buffer"))
1264                 return 0;
1265         count = tbuf_bytes(info);
1266         DBGINFO(("%s chars_in_buffer()=%d\n", info->device_name, count));
1267         return count;
1268 }
1269
1270 /*
1271  * signal remote device to throttle send data (our receive data)
1272  */
1273 static void throttle(struct tty_struct * tty)
1274 {
1275         struct slgt_info *info = tty->driver_data;
1276         unsigned long flags;
1277
1278         if (sanity_check(info, tty->name, "throttle"))
1279                 return;
1280         DBGINFO(("%s throttle\n", info->device_name));
1281         if (I_IXOFF(tty))
1282                 send_xchar(tty, STOP_CHAR(tty));
1283         if (C_CRTSCTS(tty)) {
1284                 spin_lock_irqsave(&info->lock,flags);
1285                 info->signals &= ~SerialSignal_RTS;
1286                 set_gtsignals(info);
1287                 spin_unlock_irqrestore(&info->lock,flags);
1288         }
1289 }
1290
1291 /*
1292  * signal remote device to stop throttling send data (our receive data)
1293  */
1294 static void unthrottle(struct tty_struct * tty)
1295 {
1296         struct slgt_info *info = tty->driver_data;
1297         unsigned long flags;
1298
1299         if (sanity_check(info, tty->name, "unthrottle"))
1300                 return;
1301         DBGINFO(("%s unthrottle\n", info->device_name));
1302         if (I_IXOFF(tty)) {
1303                 if (info->x_char)
1304                         info->x_char = 0;
1305                 else
1306                         send_xchar(tty, START_CHAR(tty));
1307         }
1308         if (C_CRTSCTS(tty)) {
1309                 spin_lock_irqsave(&info->lock,flags);
1310                 info->signals |= SerialSignal_RTS;
1311                 set_gtsignals(info);
1312                 spin_unlock_irqrestore(&info->lock,flags);
1313         }
1314 }
1315
1316 /*
1317  * set or clear transmit break condition
1318  * break_state  -1=set break condition, 0=clear
1319  */
1320 static int set_break(struct tty_struct *tty, int break_state)
1321 {
1322         struct slgt_info *info = tty->driver_data;
1323         unsigned short value;
1324         unsigned long flags;
1325
1326         if (sanity_check(info, tty->name, "set_break"))
1327                 return -EINVAL;
1328         DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));
1329
1330         spin_lock_irqsave(&info->lock,flags);
1331         value = rd_reg16(info, TCR);
1332         if (break_state == -1)
1333                 value |= BIT6;
1334         else
1335                 value &= ~BIT6;
1336         wr_reg16(info, TCR, value);
1337         spin_unlock_irqrestore(&info->lock,flags);
1338         return 0;
1339 }
1340
1341 #if SYNCLINK_GENERIC_HDLC
1342
1343 /**
1344  * called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1345  * set encoding and frame check sequence (FCS) options
1346  *
1347  * dev       pointer to network device structure
1348  * encoding  serial encoding setting
1349  * parity    FCS setting
1350  *
1351  * returns 0 if success, otherwise error code
1352  */
1353 static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
1354                           unsigned short parity)
1355 {
1356         struct slgt_info *info = dev_to_port(dev);
1357         unsigned char  new_encoding;
1358         unsigned short new_crctype;
1359
1360         /* return error if TTY interface open */
1361         if (info->port.count)
1362                 return -EBUSY;
1363
1364         DBGINFO(("%s hdlcdev_attach\n", info->device_name));
1365
1366         switch (encoding)
1367         {
1368         case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
1369         case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
1370         case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
1371         case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
1372         case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
1373         default: return -EINVAL;
1374         }
1375
1376         switch (parity)
1377         {
1378         case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
1379         case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
1380         case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
1381         default: return -EINVAL;
1382         }
1383
1384         info->params.encoding = new_encoding;
1385         info->params.crc_type = new_crctype;
1386
1387         /* if network interface up, reprogram hardware */
1388         if (info->netcount)
1389                 program_hw(info);
1390
1391         return 0;
1392 }
1393
1394 /**
1395  * called by generic HDLC layer to send frame
1396  *
1397  * skb  socket buffer containing HDLC frame
1398  * dev  pointer to network device structure
1399  */
1400 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1401                                       struct net_device *dev)
1402 {
1403         struct slgt_info *info = dev_to_port(dev);
1404         unsigned long flags;
1405
1406         DBGINFO(("%s hdlc_xmit\n", dev->name));
1407
1408         if (!skb->len)
1409                 return NETDEV_TX_OK;
1410
1411         /* stop sending until this frame completes */
1412         netif_stop_queue(dev);
1413
1414         /* update network statistics */
1415         dev->stats.tx_packets++;
1416         dev->stats.tx_bytes += skb->len;
1417
1418         /* save start time for transmit timeout detection */
1419         netif_trans_update(dev);
1420
1421         spin_lock_irqsave(&info->lock, flags);
1422         tx_load(info, skb->data, skb->len);
1423         spin_unlock_irqrestore(&info->lock, flags);
1424
1425         /* done with socket buffer, so free it */
1426         dev_kfree_skb(skb);
1427
1428         return NETDEV_TX_OK;
1429 }
1430
1431 /**
1432  * called by network layer when interface enabled
1433  * claim resources and initialize hardware
1434  *
1435  * dev  pointer to network device structure
1436  *
1437  * returns 0 if success, otherwise error code
1438  */
1439 static int hdlcdev_open(struct net_device *dev)
1440 {
1441         struct slgt_info *info = dev_to_port(dev);
1442         int rc;
1443         unsigned long flags;
1444
1445         if (!try_module_get(THIS_MODULE))
1446                 return -EBUSY;
1447
1448         DBGINFO(("%s hdlcdev_open\n", dev->name));
1449
1450         /* generic HDLC layer open processing */
1451         rc = hdlc_open(dev);
1452         if (rc)
1453                 return rc;
1454
1455         /* arbitrate between network and tty opens */
1456         spin_lock_irqsave(&info->netlock, flags);
1457         if (info->port.count != 0 || info->netcount != 0) {
1458                 DBGINFO(("%s hdlc_open busy\n", dev->name));
1459                 spin_unlock_irqrestore(&info->netlock, flags);
1460                 return -EBUSY;
1461         }
1462         info->netcount=1;
1463         spin_unlock_irqrestore(&info->netlock, flags);
1464
1465         /* claim resources and init adapter */
1466         if ((rc = startup(info)) != 0) {
1467                 spin_lock_irqsave(&info->netlock, flags);
1468                 info->netcount=0;
1469                 spin_unlock_irqrestore(&info->netlock, flags);
1470                 return rc;
1471         }
1472
1473         /* assert RTS and DTR, apply hardware settings */
1474         info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1475         program_hw(info);
1476
1477         /* enable network layer transmit */
1478         netif_trans_update(dev);
1479         netif_start_queue(dev);
1480
1481         /* inform generic HDLC layer of current DCD status */
1482         spin_lock_irqsave(&info->lock, flags);
1483         get_gtsignals(info);
1484         spin_unlock_irqrestore(&info->lock, flags);
1485         if (info->signals & SerialSignal_DCD)
1486                 netif_carrier_on(dev);
1487         else
1488                 netif_carrier_off(dev);
1489         return 0;
1490 }
1491
1492 /**
1493  * called by network layer when interface is disabled
1494  * shutdown hardware and release resources
1495  *
1496  * dev  pointer to network device structure
1497  *
1498  * returns 0 if success, otherwise error code
1499  */
1500 static int hdlcdev_close(struct net_device *dev)
1501 {
1502         struct slgt_info *info = dev_to_port(dev);
1503         unsigned long flags;
1504
1505         DBGINFO(("%s hdlcdev_close\n", dev->name));
1506
1507         netif_stop_queue(dev);
1508
1509         /* shutdown adapter and release resources */
1510         shutdown(info);
1511
1512         hdlc_close(dev);
1513
1514         spin_lock_irqsave(&info->netlock, flags);
1515         info->netcount=0;
1516         spin_unlock_irqrestore(&info->netlock, flags);
1517
1518         module_put(THIS_MODULE);
1519         return 0;
1520 }
1521
1522 /**
1523  * called by network layer to process IOCTL call to network device
1524  *
1525  * dev  pointer to network device structure
1526  * ifr  pointer to network interface request structure
1527  * cmd  IOCTL command code
1528  *
1529  * returns 0 if success, otherwise error code
1530  */
1531 static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1532 {
1533         const size_t size = sizeof(sync_serial_settings);
1534         sync_serial_settings new_line;
1535         sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
1536         struct slgt_info *info = dev_to_port(dev);
1537         unsigned int flags;
1538
1539         DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1540
1541         /* return error if TTY interface open */
1542         if (info->port.count)
1543                 return -EBUSY;
1544
1545         if (cmd != SIOCWANDEV)
1546                 return hdlc_ioctl(dev, ifr, cmd);
1547
1548         memset(&new_line, 0, sizeof(new_line));
1549
1550         switch(ifr->ifr_settings.type) {
1551         case IF_GET_IFACE: /* return current sync_serial_settings */
1552
1553                 ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
1554                 if (ifr->ifr_settings.size < size) {
1555                         ifr->ifr_settings.size = size; /* data size wanted */
1556                         return -ENOBUFS;
1557                 }
1558
1559                 flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1560                                               HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1561                                               HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1562                                               HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1563
1564                 switch (flags){
1565                 case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1566                 case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1567                 case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1568                 case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1569                 default: new_line.clock_type = CLOCK_DEFAULT;
1570                 }
1571
1572                 new_line.clock_rate = info->params.clock_speed;
1573                 new_line.loopback   = info->params.loopback ? 1:0;
1574
1575                 if (copy_to_user(line, &new_line, size))
1576                         return -EFAULT;
1577                 return 0;
1578
1579         case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1580
1581                 if(!capable(CAP_NET_ADMIN))
1582                         return -EPERM;
1583                 if (copy_from_user(&new_line, line, size))
1584                         return -EFAULT;
1585
1586                 switch (new_line.clock_type)
1587                 {
1588                 case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1589                 case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1590                 case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1591                 case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1592                 case CLOCK_DEFAULT:  flags = info->params.flags &
1593                                              (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1594                                               HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1595                                               HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1596                                               HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1597                 default: return -EINVAL;
1598                 }
1599
1600                 if (new_line.loopback != 0 && new_line.loopback != 1)
1601                         return -EINVAL;
1602
1603                 info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1604                                         HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1605                                         HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1606                                         HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1607                 info->params.flags |= flags;
1608
1609                 info->params.loopback = new_line.loopback;
1610
1611                 if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1612                         info->params.clock_speed = new_line.clock_rate;
1613                 else
1614                         info->params.clock_speed = 0;
1615
1616                 /* if network interface up, reprogram hardware */
1617                 if (info->netcount)
1618                         program_hw(info);
1619                 return 0;
1620
1621         default:
1622                 return hdlc_ioctl(dev, ifr, cmd);
1623         }
1624 }
1625
1626 /**
1627  * called by network layer when transmit timeout is detected
1628  *
1629  * dev  pointer to network device structure
1630  */
1631 static void hdlcdev_tx_timeout(struct net_device *dev)
1632 {
1633         struct slgt_info *info = dev_to_port(dev);
1634         unsigned long flags;
1635
1636         DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1637
1638         dev->stats.tx_errors++;
1639         dev->stats.tx_aborted_errors++;
1640
1641         spin_lock_irqsave(&info->lock,flags);
1642         tx_stop(info);
1643         spin_unlock_irqrestore(&info->lock,flags);
1644
1645         netif_wake_queue(dev);
1646 }
1647
1648 /**
1649  * called by device driver when transmit completes
1650  * reenable network layer transmit if stopped
1651  *
1652  * info  pointer to device instance information
1653  */
1654 static void hdlcdev_tx_done(struct slgt_info *info)
1655 {
1656         if (netif_queue_stopped(info->netdev))
1657                 netif_wake_queue(info->netdev);
1658 }
1659
1660 /**
1661  * called by device driver when frame received
1662  * pass frame to network layer
1663  *
1664  * info  pointer to device instance information
1665  * buf   pointer to buffer contianing frame data
1666  * size  count of data bytes in buf
1667  */
1668 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1669 {
1670         struct sk_buff *skb = dev_alloc_skb(size);
1671         struct net_device *dev = info->netdev;
1672
1673         DBGINFO(("%s hdlcdev_rx\n", dev->name));
1674
1675         if (skb == NULL) {
1676                 DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1677                 dev->stats.rx_dropped++;
1678                 return;
1679         }
1680
1681         skb_put_data(skb, buf, size);
1682
1683         skb->protocol = hdlc_type_trans(skb, dev);
1684
1685         dev->stats.rx_packets++;
1686         dev->stats.rx_bytes += size;
1687
1688         netif_rx(skb);
1689 }
1690
1691 static const struct net_device_ops hdlcdev_ops = {
1692         .ndo_open       = hdlcdev_open,
1693         .ndo_stop       = hdlcdev_close,
1694         .ndo_start_xmit = hdlc_start_xmit,
1695         .ndo_do_ioctl   = hdlcdev_ioctl,
1696         .ndo_tx_timeout = hdlcdev_tx_timeout,
1697 };
1698
1699 /**
1700  * called by device driver when adding device instance
1701  * do generic HDLC initialization
1702  *
1703  * info  pointer to device instance information
1704  *
1705  * returns 0 if success, otherwise error code
1706  */
1707 static int hdlcdev_init(struct slgt_info *info)
1708 {
1709         int rc;
1710         struct net_device *dev;
1711         hdlc_device *hdlc;
1712
1713         /* allocate and initialize network and HDLC layer objects */
1714
1715         dev = alloc_hdlcdev(info);
1716         if (!dev) {
1717                 printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1718                 return -ENOMEM;
1719         }
1720
1721         /* for network layer reporting purposes only */
1722         dev->mem_start = info->phys_reg_addr;
1723         dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1724         dev->irq       = info->irq_level;
1725
1726         /* network layer callbacks and settings */
1727         dev->netdev_ops     = &hdlcdev_ops;
1728         dev->watchdog_timeo = 10 * HZ;
1729         dev->tx_queue_len   = 50;
1730
1731         /* generic HDLC layer callbacks and settings */
1732         hdlc         = dev_to_hdlc(dev);
1733         hdlc->attach = hdlcdev_attach;
1734         hdlc->xmit   = hdlcdev_xmit;
1735
1736         /* register objects with HDLC layer */
1737         rc = register_hdlc_device(dev);
1738         if (rc) {
1739                 printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1740                 free_netdev(dev);
1741                 return rc;
1742         }
1743
1744         info->netdev = dev;
1745         return 0;
1746 }
1747
1748 /**
1749  * called by device driver when removing device instance
1750  * do generic HDLC cleanup
1751  *
1752  * info  pointer to device instance information
1753  */
1754 static void hdlcdev_exit(struct slgt_info *info)
1755 {
1756         unregister_hdlc_device(info->netdev);
1757         free_netdev(info->netdev);
1758         info->netdev = NULL;
1759 }
1760
1761 #endif /* ifdef CONFIG_HDLC */
1762
1763 /*
1764  * get async data from rx DMA buffers
1765  */
1766 static void rx_async(struct slgt_info *info)
1767 {
1768         struct mgsl_icount *icount = &info->icount;
1769         unsigned int start, end;
1770         unsigned char *p;
1771         unsigned char status;
1772         struct slgt_desc *bufs = info->rbufs;
1773         int i, count;
1774         int chars = 0;
1775         int stat;
1776         unsigned char ch;
1777
1778         start = end = info->rbuf_current;
1779
1780         while(desc_complete(bufs[end])) {
1781                 count = desc_count(bufs[end]) - info->rbuf_index;
1782                 p     = bufs[end].buf + info->rbuf_index;
1783
1784                 DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1785                 DBGDATA(info, p, count, "rx");
1786
1787                 for(i=0 ; i < count; i+=2, p+=2) {
1788                         ch = *p;
1789                         icount->rx++;
1790
1791                         stat = 0;
1792
1793                         status = *(p + 1) & (BIT1 + BIT0);
1794                         if (status) {
1795                                 if (status & BIT1)
1796                                         icount->parity++;
1797                                 else if (status & BIT0)
1798                                         icount->frame++;
1799                                 /* discard char if tty control flags say so */
1800                                 if (status & info->ignore_status_mask)
1801                                         continue;
1802                                 if (status & BIT1)
1803                                         stat = TTY_PARITY;
1804                                 else if (status & BIT0)
1805                                         stat = TTY_FRAME;
1806                         }
1807                         tty_insert_flip_char(&info->port, ch, stat);
1808                         chars++;
1809                 }
1810
1811                 if (i < count) {
1812                         /* receive buffer not completed */
1813                         info->rbuf_index += i;
1814                         mod_timer(&info->rx_timer, jiffies + 1);
1815                         break;
1816                 }
1817
1818                 info->rbuf_index = 0;
1819                 free_rbufs(info, end, end);
1820
1821                 if (++end == info->rbuf_count)
1822                         end = 0;
1823
1824                 /* if entire list searched then no frame available */
1825                 if (end == start)
1826                         break;
1827         }
1828
1829         if (chars)
1830                 tty_flip_buffer_push(&info->port);
1831 }
1832
1833 /*
1834  * return next bottom half action to perform
1835  */
1836 static int bh_action(struct slgt_info *info)
1837 {
1838         unsigned long flags;
1839         int rc;
1840
1841         spin_lock_irqsave(&info->lock,flags);
1842
1843         if (info->pending_bh & BH_RECEIVE) {
1844                 info->pending_bh &= ~BH_RECEIVE;
1845                 rc = BH_RECEIVE;
1846         } else if (info->pending_bh & BH_TRANSMIT) {
1847                 info->pending_bh &= ~BH_TRANSMIT;
1848                 rc = BH_TRANSMIT;
1849         } else if (info->pending_bh & BH_STATUS) {
1850                 info->pending_bh &= ~BH_STATUS;
1851                 rc = BH_STATUS;
1852         } else {
1853                 /* Mark BH routine as complete */
1854                 info->bh_running = false;
1855                 info->bh_requested = false;
1856                 rc = 0;
1857         }
1858
1859         spin_unlock_irqrestore(&info->lock,flags);
1860
1861         return rc;
1862 }
1863
1864 /*
1865  * perform bottom half processing
1866  */
1867 static void bh_handler(struct work_struct *work)
1868 {
1869         struct slgt_info *info = container_of(work, struct slgt_info, task);
1870         int action;
1871
1872         info->bh_running = true;
1873
1874         while((action = bh_action(info))) {
1875                 switch (action) {
1876                 case BH_RECEIVE:
1877                         DBGBH(("%s bh receive\n", info->device_name));
1878                         switch(info->params.mode) {
1879                         case MGSL_MODE_ASYNC:
1880                                 rx_async(info);
1881                                 break;
1882                         case MGSL_MODE_HDLC:
1883                                 while(rx_get_frame(info));
1884                                 break;
1885                         case MGSL_MODE_RAW:
1886                         case MGSL_MODE_MONOSYNC:
1887                         case MGSL_MODE_BISYNC:
1888                         case MGSL_MODE_XSYNC:
1889                                 while(rx_get_buf(info));
1890                                 break;
1891                         }
1892                         /* restart receiver if rx DMA buffers exhausted */
1893                         if (info->rx_restart)
1894                                 rx_start(info);
1895                         break;
1896                 case BH_TRANSMIT:
1897                         bh_transmit(info);
1898                         break;
1899                 case BH_STATUS:
1900                         DBGBH(("%s bh status\n", info->device_name));
1901                         info->ri_chkcount = 0;
1902                         info->dsr_chkcount = 0;
1903                         info->dcd_chkcount = 0;
1904                         info->cts_chkcount = 0;
1905                         break;
1906                 default:
1907                         DBGBH(("%s unknown action\n", info->device_name));
1908                         break;
1909                 }
1910         }
1911         DBGBH(("%s bh_handler exit\n", info->device_name));
1912 }
1913
1914 static void bh_transmit(struct slgt_info *info)
1915 {
1916         struct tty_struct *tty = info->port.tty;
1917
1918         DBGBH(("%s bh_transmit\n", info->device_name));
1919         if (tty)
1920                 tty_wakeup(tty);
1921 }
1922
1923 static void dsr_change(struct slgt_info *info, unsigned short status)
1924 {
1925         if (status & BIT3) {
1926                 info->signals |= SerialSignal_DSR;
1927                 info->input_signal_events.dsr_up++;
1928         } else {
1929                 info->signals &= ~SerialSignal_DSR;
1930                 info->input_signal_events.dsr_down++;
1931         }
1932         DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
1933         if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1934                 slgt_irq_off(info, IRQ_DSR);
1935                 return;
1936         }
1937         info->icount.dsr++;
1938         wake_up_interruptible(&info->status_event_wait_q);
1939         wake_up_interruptible(&info->event_wait_q);
1940         info->pending_bh |= BH_STATUS;
1941 }
1942
1943 static void cts_change(struct slgt_info *info, unsigned short status)
1944 {
1945         if (status & BIT2) {
1946                 info->signals |= SerialSignal_CTS;
1947                 info->input_signal_events.cts_up++;
1948         } else {
1949                 info->signals &= ~SerialSignal_CTS;
1950                 info->input_signal_events.cts_down++;
1951         }
1952         DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
1953         if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1954                 slgt_irq_off(info, IRQ_CTS);
1955                 return;
1956         }
1957         info->icount.cts++;
1958         wake_up_interruptible(&info->status_event_wait_q);
1959         wake_up_interruptible(&info->event_wait_q);
1960         info->pending_bh |= BH_STATUS;
1961
1962         if (tty_port_cts_enabled(&info->port)) {
1963                 if (info->port.tty) {
1964                         if (info->port.tty->hw_stopped) {
1965                                 if (info->signals & SerialSignal_CTS) {
1966                                         info->port.tty->hw_stopped = 0;
1967                                         info->pending_bh |= BH_TRANSMIT;
1968                                         return;
1969                                 }
1970                         } else {
1971                                 if (!(info->signals & SerialSignal_CTS))
1972                                         info->port.tty->hw_stopped = 1;
1973                         }
1974                 }
1975         }
1976 }
1977
1978 static void dcd_change(struct slgt_info *info, unsigned short status)
1979 {
1980         if (status & BIT1) {
1981                 info->signals |= SerialSignal_DCD;
1982                 info->input_signal_events.dcd_up++;
1983         } else {
1984                 info->signals &= ~SerialSignal_DCD;
1985                 info->input_signal_events.dcd_down++;
1986         }
1987         DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
1988         if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1989                 slgt_irq_off(info, IRQ_DCD);
1990                 return;
1991         }
1992         info->icount.dcd++;
1993 #if SYNCLINK_GENERIC_HDLC
1994         if (info->netcount) {
1995                 if (info->signals & SerialSignal_DCD)
1996                         netif_carrier_on(info->netdev);
1997                 else
1998                         netif_carrier_off(info->netdev);
1999         }
2000 #endif
2001         wake_up_interruptible(&info->status_event_wait_q);
2002         wake_up_interruptible(&info->event_wait_q);
2003         info->pending_bh |= BH_STATUS;
2004
2005         if (tty_port_check_carrier(&info->port)) {
2006                 if (info->signals & SerialSignal_DCD)
2007                         wake_up_interruptible(&info->port.open_wait);
2008                 else {
2009                         if (info->port.tty)
2010                                 tty_hangup(info->port.tty);
2011                 }
2012         }
2013 }
2014
2015 static void ri_change(struct slgt_info *info, unsigned short status)
2016 {
2017         if (status & BIT0) {
2018                 info->signals |= SerialSignal_RI;
2019                 info->input_signal_events.ri_up++;
2020         } else {
2021                 info->signals &= ~SerialSignal_RI;
2022                 info->input_signal_events.ri_down++;
2023         }
2024         DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2025         if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2026                 slgt_irq_off(info, IRQ_RI);
2027                 return;
2028         }
2029         info->icount.rng++;
2030         wake_up_interruptible(&info->status_event_wait_q);
2031         wake_up_interruptible(&info->event_wait_q);
2032         info->pending_bh |= BH_STATUS;
2033 }
2034
2035 static void isr_rxdata(struct slgt_info *info)
2036 {
2037         unsigned int count = info->rbuf_fill_count;
2038         unsigned int i = info->rbuf_fill_index;
2039         unsigned short reg;
2040
2041         while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2042                 reg = rd_reg16(info, RDR);
2043                 DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2044                 if (desc_complete(info->rbufs[i])) {
2045                         /* all buffers full */
2046                         rx_stop(info);
2047                         info->rx_restart = 1;
2048                         continue;
2049                 }
2050                 info->rbufs[i].buf[count++] = (unsigned char)reg;
2051                 /* async mode saves status byte to buffer for each data byte */
2052                 if (info->params.mode == MGSL_MODE_ASYNC)
2053                         info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2054                 if (count == info->rbuf_fill_level || (reg & BIT10)) {
2055                         /* buffer full or end of frame */
2056                         set_desc_count(info->rbufs[i], count);
2057                         set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2058                         info->rbuf_fill_count = count = 0;
2059                         if (++i == info->rbuf_count)
2060                                 i = 0;
2061                         info->pending_bh |= BH_RECEIVE;
2062                 }
2063         }
2064
2065         info->rbuf_fill_index = i;
2066         info->rbuf_fill_count = count;
2067 }
2068
2069 static void isr_serial(struct slgt_info *info)
2070 {
2071         unsigned short status = rd_reg16(info, SSR);
2072
2073         DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2074
2075         wr_reg16(info, SSR, status); /* clear pending */
2076
2077         info->irq_occurred = true;
2078
2079         if (info->params.mode == MGSL_MODE_ASYNC) {
2080                 if (status & IRQ_TXIDLE) {
2081                         if (info->tx_active)
2082                                 isr_txeom(info, status);
2083                 }
2084                 if (info->rx_pio && (status & IRQ_RXDATA))
2085                         isr_rxdata(info);
2086                 if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2087                         info->icount.brk++;
2088                         /* process break detection if tty control allows */
2089                         if (info->port.tty) {
2090                                 if (!(status & info->ignore_status_mask)) {
2091                                         if (info->read_status_mask & MASK_BREAK) {
2092                                                 tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2093                                                 if (info->port.flags & ASYNC_SAK)
2094                                                         do_SAK(info->port.tty);
2095                                         }
2096                                 }
2097                         }
2098                 }
2099         } else {
2100                 if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2101                         isr_txeom(info, status);
2102                 if (info->rx_pio && (status & IRQ_RXDATA))
2103                         isr_rxdata(info);
2104                 if (status & IRQ_RXIDLE) {
2105                         if (status & RXIDLE)
2106                                 info->icount.rxidle++;
2107                         else
2108                                 info->icount.exithunt++;
2109                         wake_up_interruptible(&info->event_wait_q);
2110                 }
2111
2112                 if (status & IRQ_RXOVER)
2113                         rx_start(info);
2114         }
2115
2116         if (status & IRQ_DSR)
2117                 dsr_change(info, status);
2118         if (status & IRQ_CTS)
2119                 cts_change(info, status);
2120         if (status & IRQ_DCD)
2121                 dcd_change(info, status);
2122         if (status & IRQ_RI)
2123                 ri_change(info, status);
2124 }
2125
2126 static void isr_rdma(struct slgt_info *info)
2127 {
2128         unsigned int status = rd_reg32(info, RDCSR);
2129
2130         DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2131
2132         /* RDCSR (rx DMA control/status)
2133          *
2134          * 31..07  reserved
2135          * 06      save status byte to DMA buffer
2136          * 05      error
2137          * 04      eol (end of list)
2138          * 03      eob (end of buffer)
2139          * 02      IRQ enable
2140          * 01      reset
2141          * 00      enable
2142          */
2143         wr_reg32(info, RDCSR, status);  /* clear pending */
2144
2145         if (status & (BIT5 + BIT4)) {
2146                 DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2147                 info->rx_restart = true;
2148         }
2149         info->pending_bh |= BH_RECEIVE;
2150 }
2151
2152 static void isr_tdma(struct slgt_info *info)
2153 {
2154         unsigned int status = rd_reg32(info, TDCSR);
2155
2156         DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2157
2158         /* TDCSR (tx DMA control/status)
2159          *
2160          * 31..06  reserved
2161          * 05      error
2162          * 04      eol (end of list)
2163          * 03      eob (end of buffer)
2164          * 02      IRQ enable
2165          * 01      reset
2166          * 00      enable
2167          */
2168         wr_reg32(info, TDCSR, status);  /* clear pending */
2169
2170         if (status & (BIT5 + BIT4 + BIT3)) {
2171                 // another transmit buffer has completed
2172                 // run bottom half to get more send data from user
2173                 info->pending_bh |= BH_TRANSMIT;
2174         }
2175 }
2176
2177 /*
2178  * return true if there are unsent tx DMA buffers, otherwise false
2179  *
2180  * if there are unsent buffers then info->tbuf_start
2181  * is set to index of first unsent buffer
2182  */
2183 static bool unsent_tbufs(struct slgt_info *info)
2184 {
2185         unsigned int i = info->tbuf_current;
2186         bool rc = false;
2187
2188         /*
2189          * search backwards from last loaded buffer (precedes tbuf_current)
2190          * for first unsent buffer (desc_count > 0)
2191          */
2192
2193         do {
2194                 if (i)
2195                         i--;
2196                 else
2197                         i = info->tbuf_count - 1;
2198                 if (!desc_count(info->tbufs[i]))
2199                         break;
2200                 info->tbuf_start = i;
2201                 rc = true;
2202         } while (i != info->tbuf_current);
2203
2204         return rc;
2205 }
2206
2207 static void isr_txeom(struct slgt_info *info, unsigned short status)
2208 {
2209         DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2210
2211         slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2212         tdma_reset(info);
2213         if (status & IRQ_TXUNDER) {
2214                 unsigned short val = rd_reg16(info, TCR);
2215                 wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2216                 wr_reg16(info, TCR, val); /* clear reset bit */
2217         }
2218
2219         if (info->tx_active) {
2220                 if (info->params.mode != MGSL_MODE_ASYNC) {
2221                         if (status & IRQ_TXUNDER)
2222                                 info->icount.txunder++;
2223                         else if (status & IRQ_TXIDLE)
2224                                 info->icount.txok++;
2225                 }
2226
2227                 if (unsent_tbufs(info)) {
2228                         tx_start(info);
2229                         update_tx_timer(info);
2230                         return;
2231                 }
2232                 info->tx_active = false;
2233
2234                 del_timer(&info->tx_timer);
2235
2236                 if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2237                         info->signals &= ~SerialSignal_RTS;
2238                         info->drop_rts_on_tx_done = false;
2239                         set_gtsignals(info);
2240                 }
2241
2242 #if SYNCLINK_GENERIC_HDLC
2243                 if (info->netcount)
2244                         hdlcdev_tx_done(info);
2245                 else
2246 #endif
2247                 {
2248                         if (info->port.tty && (info->port.tty->stopped || info->port.tty->hw_stopped)) {
2249                                 tx_stop(info);
2250                                 return;
2251                         }
2252                         info->pending_bh |= BH_TRANSMIT;
2253                 }
2254         }
2255 }
2256
2257 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2258 {
2259         struct cond_wait *w, *prev;
2260
2261         /* wake processes waiting for specific transitions */
2262         for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2263                 if (w->data & changed) {
2264                         w->data = state;
2265                         wake_up_interruptible(&w->q);
2266                         if (prev != NULL)
2267                                 prev->next = w->next;
2268                         else
2269                                 info->gpio_wait_q = w->next;
2270                 } else
2271                         prev = w;
2272         }
2273 }
2274
2275 /* interrupt service routine
2276  *
2277  *      irq     interrupt number
2278  *      dev_id  device ID supplied during interrupt registration
2279  */
2280 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2281 {
2282         struct slgt_info *info = dev_id;
2283         unsigned int gsr;
2284         unsigned int i;
2285
2286         DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2287
2288         while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2289                 DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2290                 info->irq_occurred = true;
2291                 for(i=0; i < info->port_count ; i++) {
2292                         if (info->port_array[i] == NULL)
2293                                 continue;
2294                         spin_lock(&info->port_array[i]->lock);
2295                         if (gsr & (BIT8 << i))
2296                                 isr_serial(info->port_array[i]);
2297                         if (gsr & (BIT16 << (i*2)))
2298                                 isr_rdma(info->port_array[i]);
2299                         if (gsr & (BIT17 << (i*2)))
2300                                 isr_tdma(info->port_array[i]);
2301                         spin_unlock(&info->port_array[i]->lock);
2302                 }
2303         }
2304
2305         if (info->gpio_present) {
2306                 unsigned int state;
2307                 unsigned int changed;
2308                 spin_lock(&info->lock);
2309                 while ((changed = rd_reg32(info, IOSR)) != 0) {
2310                         DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2311                         /* read latched state of GPIO signals */
2312                         state = rd_reg32(info, IOVR);
2313                         /* clear pending GPIO interrupt bits */
2314                         wr_reg32(info, IOSR, changed);
2315                         for (i=0 ; i < info->port_count ; i++) {
2316                                 if (info->port_array[i] != NULL)
2317                                         isr_gpio(info->port_array[i], changed, state);
2318                         }
2319                 }
2320                 spin_unlock(&info->lock);
2321         }
2322
2323         for(i=0; i < info->port_count ; i++) {
2324                 struct slgt_info *port = info->port_array[i];
2325                 if (port == NULL)
2326                         continue;
2327                 spin_lock(&port->lock);
2328                 if ((port->port.count || port->netcount) &&
2329                     port->pending_bh && !port->bh_running &&
2330                     !port->bh_requested) {
2331                         DBGISR(("%s bh queued\n", port->device_name));
2332                         schedule_work(&port->task);
2333                         port->bh_requested = true;
2334                 }
2335                 spin_unlock(&port->lock);
2336         }
2337
2338         DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2339         return IRQ_HANDLED;
2340 }
2341
2342 static int startup(struct slgt_info *info)
2343 {
2344         DBGINFO(("%s startup\n", info->device_name));
2345
2346         if (tty_port_initialized(&info->port))
2347                 return 0;
2348
2349         if (!info->tx_buf) {
2350                 info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2351                 if (!info->tx_buf) {
2352                         DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2353                         return -ENOMEM;
2354                 }
2355         }
2356
2357         info->pending_bh = 0;
2358
2359         memset(&info->icount, 0, sizeof(info->icount));
2360
2361         /* program hardware for current parameters */
2362         change_params(info);
2363
2364         if (info->port.tty)
2365                 clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2366
2367         tty_port_set_initialized(&info->port, 1);
2368
2369         return 0;
2370 }
2371
2372 /*
2373  *  called by close() and hangup() to shutdown hardware
2374  */
2375 static void shutdown(struct slgt_info *info)
2376 {
2377         unsigned long flags;
2378
2379         if (!tty_port_initialized(&info->port))
2380                 return;
2381
2382         DBGINFO(("%s shutdown\n", info->device_name));
2383
2384         /* clear status wait queue because status changes */
2385         /* can't happen after shutting down the hardware */
2386         wake_up_interruptible(&info->status_event_wait_q);
2387         wake_up_interruptible(&info->event_wait_q);
2388
2389         del_timer_sync(&info->tx_timer);
2390         del_timer_sync(&info->rx_timer);
2391
2392         kfree(info->tx_buf);
2393         info->tx_buf = NULL;
2394
2395         spin_lock_irqsave(&info->lock,flags);
2396
2397         tx_stop(info);
2398         rx_stop(info);
2399
2400         slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2401
2402         if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2403                 info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2404                 set_gtsignals(info);
2405         }
2406
2407         flush_cond_wait(&info->gpio_wait_q);
2408
2409         spin_unlock_irqrestore(&info->lock,flags);
2410
2411         if (info->port.tty)
2412                 set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2413
2414         tty_port_set_initialized(&info->port, 0);
2415 }
2416
2417 static void program_hw(struct slgt_info *info)
2418 {
2419         unsigned long flags;
2420
2421         spin_lock_irqsave(&info->lock,flags);
2422
2423         rx_stop(info);
2424         tx_stop(info);
2425
2426         if (info->params.mode != MGSL_MODE_ASYNC ||
2427             info->netcount)
2428                 sync_mode(info);
2429         else
2430                 async_mode(info);
2431
2432         set_gtsignals(info);
2433
2434         info->dcd_chkcount = 0;
2435         info->cts_chkcount = 0;
2436         info->ri_chkcount = 0;
2437         info->dsr_chkcount = 0;
2438
2439         slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2440         get_gtsignals(info);
2441
2442         if (info->netcount ||
2443             (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2444                 rx_start(info);
2445
2446         spin_unlock_irqrestore(&info->lock,flags);
2447 }
2448
2449 /*
2450  * reconfigure adapter based on new parameters
2451  */
2452 static void change_params(struct slgt_info *info)
2453 {
2454         unsigned cflag;
2455         int bits_per_char;
2456
2457         if (!info->port.tty)
2458                 return;
2459         DBGINFO(("%s change_params\n", info->device_name));
2460
2461         cflag = info->port.tty->termios.c_cflag;
2462
2463         /* if B0 rate (hangup) specified then negate RTS and DTR */
2464         /* otherwise assert RTS and DTR */
2465         if (cflag & CBAUD)
2466                 info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2467         else
2468                 info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2469
2470         /* byte size and parity */
2471
2472         switch (cflag & CSIZE) {
2473         case CS5: info->params.data_bits = 5; break;
2474         case CS6: info->params.data_bits = 6; break;
2475         case CS7: info->params.data_bits = 7; break;
2476         case CS8: info->params.data_bits = 8; break;
2477         default:  info->params.data_bits = 7; break;
2478         }
2479
2480         info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2481
2482         if (cflag & PARENB)
2483                 info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2484         else
2485                 info->params.parity = ASYNC_PARITY_NONE;
2486
2487         /* calculate number of jiffies to transmit a full
2488          * FIFO (32 bytes) at specified data rate
2489          */
2490         bits_per_char = info->params.data_bits +
2491                         info->params.stop_bits + 1;
2492
2493         info->params.data_rate = tty_get_baud_rate(info->port.tty);
2494
2495         if (info->params.data_rate) {
2496                 info->timeout = (32*HZ*bits_per_char) /
2497                                 info->params.data_rate;
2498         }
2499         info->timeout += HZ/50;         /* Add .02 seconds of slop */
2500
2501         tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2502         tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2503
2504         /* process tty input control flags */
2505
2506         info->read_status_mask = IRQ_RXOVER;
2507         if (I_INPCK(info->port.tty))
2508                 info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2509         if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2510                 info->read_status_mask |= MASK_BREAK;
2511         if (I_IGNPAR(info->port.tty))
2512                 info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2513         if (I_IGNBRK(info->port.tty)) {
2514                 info->ignore_status_mask |= MASK_BREAK;
2515                 /* If ignoring parity and break indicators, ignore
2516                  * overruns too.  (For real raw support).
2517                  */
2518                 if (I_IGNPAR(info->port.tty))
2519                         info->ignore_status_mask |= MASK_OVERRUN;
2520         }
2521
2522         program_hw(info);
2523 }
2524
2525 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2526 {
2527         DBGINFO(("%s get_stats\n",  info->device_name));
2528         if (!user_icount) {
2529                 memset(&info->icount, 0, sizeof(info->icount));
2530         } else {
2531                 if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2532                         return -EFAULT;
2533         }
2534         return 0;
2535 }
2536
2537 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2538 {
2539         DBGINFO(("%s get_params\n", info->device_name));
2540         if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2541                 return -EFAULT;
2542         return 0;
2543 }
2544
2545 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2546 {
2547         unsigned long flags;
2548         MGSL_PARAMS tmp_params;
2549
2550         DBGINFO(("%s set_params\n", info->device_name));
2551         if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2552                 return -EFAULT;
2553
2554         spin_lock_irqsave(&info->lock, flags);
2555         if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2556                 info->base_clock = tmp_params.clock_speed;
2557         else
2558                 memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2559         spin_unlock_irqrestore(&info->lock, flags);
2560
2561         program_hw(info);
2562
2563         return 0;
2564 }
2565
2566 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2567 {
2568         DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2569         if (put_user(info->idle_mode, idle_mode))
2570                 return -EFAULT;
2571         return 0;
2572 }
2573
2574 static int set_txidle(struct slgt_info *info, int idle_mode)
2575 {
2576         unsigned long flags;
2577         DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2578         spin_lock_irqsave(&info->lock,flags);
2579         info->idle_mode = idle_mode;
2580         if (info->params.mode != MGSL_MODE_ASYNC)
2581                 tx_set_idle(info);
2582         spin_unlock_irqrestore(&info->lock,flags);
2583         return 0;
2584 }
2585
2586 static int tx_enable(struct slgt_info *info, int enable)
2587 {
2588         unsigned long flags;
2589         DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2590         spin_lock_irqsave(&info->lock,flags);
2591         if (enable) {
2592                 if (!info->tx_enabled)
2593                         tx_start(info);
2594         } else {
2595                 if (info->tx_enabled)
2596                         tx_stop(info);
2597         }
2598         spin_unlock_irqrestore(&info->lock,flags);
2599         return 0;
2600 }
2601
2602 /*
2603  * abort transmit HDLC frame
2604  */
2605 static int tx_abort(struct slgt_info *info)
2606 {
2607         unsigned long flags;
2608         DBGINFO(("%s tx_abort\n", info->device_name));
2609         spin_lock_irqsave(&info->lock,flags);
2610         tdma_reset(info);
2611         spin_unlock_irqrestore(&info->lock,flags);
2612         return 0;
2613 }
2614
2615 static int rx_enable(struct slgt_info *info, int enable)
2616 {
2617         unsigned long flags;
2618         unsigned int rbuf_fill_level;
2619         DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2620         spin_lock_irqsave(&info->lock,flags);
2621         /*
2622          * enable[31..16] = receive DMA buffer fill level
2623          * 0 = noop (leave fill level unchanged)
2624          * fill level must be multiple of 4 and <= buffer size
2625          */
2626         rbuf_fill_level = ((unsigned int)enable) >> 16;
2627         if (rbuf_fill_level) {
2628                 if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2629                         spin_unlock_irqrestore(&info->lock, flags);
2630                         return -EINVAL;
2631                 }
2632                 info->rbuf_fill_level = rbuf_fill_level;
2633                 if (rbuf_fill_level < 128)
2634                         info->rx_pio = 1; /* PIO mode */
2635                 else
2636                         info->rx_pio = 0; /* DMA mode */
2637                 rx_stop(info); /* restart receiver to use new fill level */
2638         }
2639
2640         /*
2641          * enable[1..0] = receiver enable command
2642          * 0 = disable
2643          * 1 = enable
2644          * 2 = enable or force hunt mode if already enabled
2645          */
2646         enable &= 3;
2647         if (enable) {
2648                 if (!info->rx_enabled)
2649                         rx_start(info);
2650                 else if (enable == 2) {
2651                         /* force hunt mode (write 1 to RCR[3]) */
2652                         wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2653                 }
2654         } else {
2655                 if (info->rx_enabled)
2656                         rx_stop(info);
2657         }
2658         spin_unlock_irqrestore(&info->lock,flags);
2659         return 0;
2660 }
2661
2662 /*
2663  *  wait for specified event to occur
2664  */
2665 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2666 {
2667         unsigned long flags;
2668         int s;
2669         int rc=0;
2670         struct mgsl_icount cprev, cnow;
2671         int events;
2672         int mask;
2673         struct  _input_signal_events oldsigs, newsigs;
2674         DECLARE_WAITQUEUE(wait, current);
2675
2676         if (get_user(mask, mask_ptr))
2677                 return -EFAULT;
2678
2679         DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2680
2681         spin_lock_irqsave(&info->lock,flags);
2682
2683         /* return immediately if state matches requested events */
2684         get_gtsignals(info);
2685         s = info->signals;
2686
2687         events = mask &
2688                 ( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2689                   ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2690                   ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2691                   ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2692         if (events) {
2693                 spin_unlock_irqrestore(&info->lock,flags);
2694                 goto exit;
2695         }
2696
2697         /* save current irq counts */
2698         cprev = info->icount;
2699         oldsigs = info->input_signal_events;
2700
2701         /* enable hunt and idle irqs if needed */
2702         if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2703                 unsigned short val = rd_reg16(info, SCR);
2704                 if (!(val & IRQ_RXIDLE))
2705                         wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2706         }
2707
2708         set_current_state(TASK_INTERRUPTIBLE);
2709         add_wait_queue(&info->event_wait_q, &wait);
2710
2711         spin_unlock_irqrestore(&info->lock,flags);
2712
2713         for(;;) {
2714                 schedule();
2715                 if (signal_pending(current)) {
2716                         rc = -ERESTARTSYS;
2717                         break;
2718                 }
2719
2720                 /* get current irq counts */
2721                 spin_lock_irqsave(&info->lock,flags);
2722                 cnow = info->icount;
2723                 newsigs = info->input_signal_events;
2724                 set_current_state(TASK_INTERRUPTIBLE);
2725                 spin_unlock_irqrestore(&info->lock,flags);
2726
2727                 /* if no change, wait aborted for some reason */
2728                 if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2729                     newsigs.dsr_down == oldsigs.dsr_down &&
2730                     newsigs.dcd_up   == oldsigs.dcd_up   &&
2731                     newsigs.dcd_down == oldsigs.dcd_down &&
2732                     newsigs.cts_up   == oldsigs.cts_up   &&
2733                     newsigs.cts_down == oldsigs.cts_down &&
2734                     newsigs.ri_up    == oldsigs.ri_up    &&
2735                     newsigs.ri_down  == oldsigs.ri_down  &&
2736                     cnow.exithunt    == cprev.exithunt   &&
2737                     cnow.rxidle      == cprev.rxidle) {
2738                         rc = -EIO;
2739                         break;
2740                 }
2741
2742                 events = mask &
2743                         ( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2744                           (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2745                           (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2746                           (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2747                           (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2748                           (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2749                           (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2750                           (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2751                           (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2752                           (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2753                 if (events)
2754                         break;
2755
2756                 cprev = cnow;
2757                 oldsigs = newsigs;
2758         }
2759
2760         remove_wait_queue(&info->event_wait_q, &wait);
2761         set_current_state(TASK_RUNNING);
2762
2763
2764         if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2765                 spin_lock_irqsave(&info->lock,flags);
2766                 if (!waitqueue_active(&info->event_wait_q)) {
2767                         /* disable enable exit hunt mode/idle rcvd IRQs */
2768                         wr_reg16(info, SCR,
2769                                 (unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2770                 }
2771                 spin_unlock_irqrestore(&info->lock,flags);
2772         }
2773 exit:
2774         if (rc == 0)
2775                 rc = put_user(events, mask_ptr);
2776         return rc;
2777 }
2778
2779 static int get_interface(struct slgt_info *info, int __user *if_mode)
2780 {
2781         DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2782         if (put_user(info->if_mode, if_mode))
2783                 return -EFAULT;
2784         return 0;
2785 }
2786
2787 static int set_interface(struct slgt_info *info, int if_mode)
2788 {
2789         unsigned long flags;
2790         unsigned short val;
2791
2792         DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2793         spin_lock_irqsave(&info->lock,flags);
2794         info->if_mode = if_mode;
2795
2796         msc_set_vcr(info);
2797
2798         /* TCR (tx control) 07  1=RTS driver control */
2799         val = rd_reg16(info, TCR);
2800         if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2801                 val |= BIT7;
2802         else
2803                 val &= ~BIT7;
2804         wr_reg16(info, TCR, val);
2805
2806         spin_unlock_irqrestore(&info->lock,flags);
2807         return 0;
2808 }
2809
2810 static int get_xsync(struct slgt_info *info, int __user *xsync)
2811 {
2812         DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2813         if (put_user(info->xsync, xsync))
2814                 return -EFAULT;
2815         return 0;
2816 }
2817
2818 /*
2819  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2820  *
2821  * sync pattern is contained in least significant bytes of value
2822  * most significant byte of sync pattern is oldest (1st sent/detected)
2823  */
2824 static int set_xsync(struct slgt_info *info, int xsync)
2825 {
2826         unsigned long flags;
2827
2828         DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2829         spin_lock_irqsave(&info->lock, flags);
2830         info->xsync = xsync;
2831         wr_reg32(info, XSR, xsync);
2832         spin_unlock_irqrestore(&info->lock, flags);
2833         return 0;
2834 }
2835
2836 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2837 {
2838         DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2839         if (put_user(info->xctrl, xctrl))
2840                 return -EFAULT;
2841         return 0;
2842 }
2843
2844 /*
2845  * set extended control options
2846  *
2847  * xctrl[31:19] reserved, must be zero
2848  * xctrl[18:17] extended sync pattern length in bytes
2849  *              00 = 1 byte  in xsr[7:0]
2850  *              01 = 2 bytes in xsr[15:0]
2851  *              10 = 3 bytes in xsr[23:0]
2852  *              11 = 4 bytes in xsr[31:0]
2853  * xctrl[16]    1 = enable terminal count, 0=disabled
2854  * xctrl[15:0]  receive terminal count for fixed length packets
2855  *              value is count minus one (0 = 1 byte packet)
2856  *              when terminal count is reached, receiver
2857  *              automatically returns to hunt mode and receive
2858  *              FIFO contents are flushed to DMA buffers with
2859  *              end of frame (EOF) status
2860  */
2861 static int set_xctrl(struct slgt_info *info, int xctrl)
2862 {
2863         unsigned long flags;
2864
2865         DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2866         spin_lock_irqsave(&info->lock, flags);
2867         info->xctrl = xctrl;
2868         wr_reg32(info, XCR, xctrl);
2869         spin_unlock_irqrestore(&info->lock, flags);
2870         return 0;
2871 }
2872
2873 /*
2874  * set general purpose IO pin state and direction
2875  *
2876  * user_gpio fields:
2877  * state   each bit indicates a pin state
2878  * smask   set bit indicates pin state to set
2879  * dir     each bit indicates a pin direction (0=input, 1=output)
2880  * dmask   set bit indicates pin direction to set
2881  */
2882 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2883 {
2884         unsigned long flags;
2885         struct gpio_desc gpio;
2886         __u32 data;
2887
2888         if (!info->gpio_present)
2889                 return -EINVAL;
2890         if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2891                 return -EFAULT;
2892         DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2893                  info->device_name, gpio.state, gpio.smask,
2894                  gpio.dir, gpio.dmask));
2895
2896         spin_lock_irqsave(&info->port_array[0]->lock, flags);
2897         if (gpio.dmask) {
2898                 data = rd_reg32(info, IODR);
2899                 data |= gpio.dmask & gpio.dir;
2900                 data &= ~(gpio.dmask & ~gpio.dir);
2901                 wr_reg32(info, IODR, data);
2902         }
2903         if (gpio.smask) {
2904                 data = rd_reg32(info, IOVR);
2905                 data |= gpio.smask & gpio.state;
2906                 data &= ~(gpio.smask & ~gpio.state);
2907                 wr_reg32(info, IOVR, data);
2908         }
2909         spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2910
2911         return 0;
2912 }
2913
2914 /*
2915  * get general purpose IO pin state and direction
2916  */
2917 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2918 {
2919         struct gpio_desc gpio;
2920         if (!info->gpio_present)
2921                 return -EINVAL;
2922         gpio.state = rd_reg32(info, IOVR);
2923         gpio.smask = 0xffffffff;
2924         gpio.dir   = rd_reg32(info, IODR);
2925         gpio.dmask = 0xffffffff;
2926         if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
2927                 return -EFAULT;
2928         DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
2929                  info->device_name, gpio.state, gpio.dir));
2930         return 0;
2931 }
2932
2933 /*
2934  * conditional wait facility
2935  */
2936 static void init_cond_wait(struct cond_wait *w, unsigned int data)
2937 {
2938         init_waitqueue_head(&w->q);
2939         init_waitqueue_entry(&w->wait, current);
2940         w->data = data;
2941 }
2942
2943 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
2944 {
2945         set_current_state(TASK_INTERRUPTIBLE);
2946         add_wait_queue(&w->q, &w->wait);
2947         w->next = *head;
2948         *head = w;
2949 }
2950
2951 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
2952 {
2953         struct cond_wait *w, *prev;
2954         remove_wait_queue(&cw->q, &cw->wait);
2955         set_current_state(TASK_RUNNING);
2956         for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
2957                 if (w == cw) {
2958                         if (prev != NULL)
2959                                 prev->next = w->next;
2960                         else
2961                                 *head = w->next;
2962                         break;
2963                 }
2964         }
2965 }
2966
2967 static void flush_cond_wait(struct cond_wait **head)
2968 {
2969         while (*head != NULL) {
2970                 wake_up_interruptible(&(*head)->q);
2971                 *head = (*head)->next;
2972         }
2973 }
2974
2975 /*
2976  * wait for general purpose I/O pin(s) to enter specified state
2977  *
2978  * user_gpio fields:
2979  * state - bit indicates target pin state
2980  * smask - set bit indicates watched pin
2981  *
2982  * The wait ends when at least one watched pin enters the specified
2983  * state. When 0 (no error) is returned, user_gpio->state is set to the
2984  * state of all GPIO pins when the wait ends.
2985  *
2986  * Note: Each pin may be a dedicated input, dedicated output, or
2987  * configurable input/output. The number and configuration of pins
2988  * varies with the specific adapter model. Only input pins (dedicated
2989  * or configured) can be monitored with this function.
2990  */
2991 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2992 {
2993         unsigned long flags;
2994         int rc = 0;
2995         struct gpio_desc gpio;
2996         struct cond_wait wait;
2997         u32 state;
2998
2999         if (!info->gpio_present)
3000                 return -EINVAL;
3001         if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
3002                 return -EFAULT;
3003         DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
3004                  info->device_name, gpio.state, gpio.smask));
3005         /* ignore output pins identified by set IODR bit */
3006         if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
3007                 return -EINVAL;
3008         init_cond_wait(&wait, gpio.smask);
3009
3010         spin_lock_irqsave(&info->port_array[0]->lock, flags);
3011         /* enable interrupts for watched pins */
3012         wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
3013         /* get current pin states */
3014         state = rd_reg32(info, IOVR);
3015
3016         if (gpio.smask & ~(state ^ gpio.state)) {
3017                 /* already in target state */
3018                 gpio.state = state;
3019         } else {
3020                 /* wait for target state */
3021                 add_cond_wait(&info->gpio_wait_q, &wait);
3022                 spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3023                 schedule();
3024                 if (signal_pending(current))
3025                         rc = -ERESTARTSYS;
3026                 else
3027                         gpio.state = wait.data;
3028                 spin_lock_irqsave(&info->port_array[0]->lock, flags);
3029                 remove_cond_wait(&info->gpio_wait_q, &wait);
3030         }
3031
3032         /* disable all GPIO interrupts if no waiting processes */
3033         if (info->gpio_wait_q == NULL)
3034                 wr_reg32(info, IOER, 0);
3035         spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3036
3037         if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3038                 rc = -EFAULT;
3039         return rc;
3040 }
3041
3042 static int modem_input_wait(struct slgt_info *info,int arg)
3043 {
3044         unsigned long flags;
3045         int rc;
3046         struct mgsl_icount cprev, cnow;
3047         DECLARE_WAITQUEUE(wait, current);
3048
3049         /* save current irq counts */
3050         spin_lock_irqsave(&info->lock,flags);
3051         cprev = info->icount;
3052         add_wait_queue(&info->status_event_wait_q, &wait);
3053         set_current_state(TASK_INTERRUPTIBLE);
3054         spin_unlock_irqrestore(&info->lock,flags);
3055
3056         for(;;) {
3057                 schedule();
3058                 if (signal_pending(current)) {
3059                         rc = -ERESTARTSYS;
3060                         break;
3061                 }
3062
3063                 /* get new irq counts */
3064                 spin_lock_irqsave(&info->lock,flags);
3065                 cnow = info->icount;
3066                 set_current_state(TASK_INTERRUPTIBLE);
3067                 spin_unlock_irqrestore(&info->lock,flags);
3068
3069                 /* if no change, wait aborted for some reason */
3070                 if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3071                     cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3072                         rc = -EIO;
3073                         break;
3074                 }
3075
3076                 /* check for change in caller specified modem input */
3077                 if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3078                     (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3079                     (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3080                     (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3081                         rc = 0;
3082                         break;
3083                 }
3084
3085                 cprev = cnow;
3086         }
3087         remove_wait_queue(&info->status_event_wait_q, &wait);
3088         set_current_state(TASK_RUNNING);
3089         return rc;
3090 }
3091
3092 /*
3093  *  return state of serial control and status signals
3094  */
3095 static int tiocmget(struct tty_struct *tty)
3096 {
3097         struct slgt_info *info = tty->driver_data;
3098         unsigned int result;
3099         unsigned long flags;
3100
3101         spin_lock_irqsave(&info->lock,flags);
3102         get_gtsignals(info);
3103         spin_unlock_irqrestore(&info->lock,flags);
3104
3105         result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3106                 ((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3107                 ((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3108                 ((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3109                 ((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3110                 ((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3111
3112         DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3113         return result;
3114 }
3115
3116 /*
3117  * set modem control signals (DTR/RTS)
3118  *
3119  *      cmd     signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3120  *              TIOCMSET = set/clear signal values
3121  *      value   bit mask for command
3122  */
3123 static int tiocmset(struct tty_struct *tty,
3124                     unsigned int set, unsigned int clear)
3125 {
3126         struct slgt_info *info = tty->driver_data;
3127         unsigned long flags;
3128
3129         DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3130
3131         if (set & TIOCM_RTS)
3132                 info->signals |= SerialSignal_RTS;
3133         if (set & TIOCM_DTR)
3134                 info->signals |= SerialSignal_DTR;
3135         if (clear & TIOCM_RTS)
3136                 info->signals &= ~SerialSignal_RTS;
3137         if (clear & TIOCM_DTR)
3138                 info->signals &= ~SerialSignal_DTR;
3139
3140         spin_lock_irqsave(&info->lock,flags);
3141         set_gtsignals(info);
3142         spin_unlock_irqrestore(&info->lock,flags);
3143         return 0;
3144 }
3145
3146 static int carrier_raised(struct tty_port *port)
3147 {
3148         unsigned long flags;
3149         struct slgt_info *info = container_of(port, struct slgt_info, port);
3150
3151         spin_lock_irqsave(&info->lock,flags);
3152         get_gtsignals(info);
3153         spin_unlock_irqrestore(&info->lock,flags);
3154         return (info->signals & SerialSignal_DCD) ? 1 : 0;
3155 }
3156
3157 static void dtr_rts(struct tty_port *port, int on)
3158 {
3159         unsigned long flags;
3160         struct slgt_info *info = container_of(port, struct slgt_info, port);
3161
3162         spin_lock_irqsave(&info->lock,flags);
3163         if (on)
3164                 info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3165         else
3166                 info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3167         set_gtsignals(info);
3168         spin_unlock_irqrestore(&info->lock,flags);
3169 }
3170
3171
3172 /*
3173  *  block current process until the device is ready to open
3174  */
3175 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3176                            struct slgt_info *info)
3177 {
3178         DECLARE_WAITQUEUE(wait, current);
3179         int             retval;
3180         bool            do_clocal = false;
3181         unsigned long   flags;
3182         int             cd;
3183         struct tty_port *port = &info->port;
3184
3185         DBGINFO(("%s block_til_ready\n", tty->driver->name));
3186
3187         if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3188                 /* nonblock mode is set or port is not enabled */
3189                 tty_port_set_active(port, 1);
3190                 return 0;
3191         }
3192
3193         if (C_CLOCAL(tty))
3194                 do_clocal = true;
3195
3196         /* Wait for carrier detect and the line to become
3197          * free (i.e., not in use by the callout).  While we are in
3198          * this loop, port->count is dropped by one, so that
3199          * close() knows when to free things.  We restore it upon
3200          * exit, either normal or abnormal.
3201          */
3202
3203         retval = 0;
3204         add_wait_queue(&port->open_wait, &wait);
3205
3206         spin_lock_irqsave(&info->lock, flags);
3207         port->count--;
3208         spin_unlock_irqrestore(&info->lock, flags);
3209         port->blocked_open++;
3210
3211         while (1) {
3212                 if (C_BAUD(tty) && tty_port_initialized(port))
3213                         tty_port_raise_dtr_rts(port);
3214
3215                 set_current_state(TASK_INTERRUPTIBLE);
3216
3217                 if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3218                         retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3219                                         -EAGAIN : -ERESTARTSYS;
3220                         break;
3221                 }
3222
3223                 cd = tty_port_carrier_raised(port);
3224                 if (do_clocal || cd)
3225                         break;
3226
3227                 if (signal_pending(current)) {
3228                         retval = -ERESTARTSYS;
3229                         break;
3230                 }
3231
3232                 DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3233                 tty_unlock(tty);
3234                 schedule();
3235                 tty_lock(tty);
3236         }
3237
3238         set_current_state(TASK_RUNNING);
3239         remove_wait_queue(&port->open_wait, &wait);
3240
3241         if (!tty_hung_up_p(filp))
3242                 port->count++;
3243         port->blocked_open--;
3244
3245         if (!retval)
3246                 tty_port_set_active(port, 1);
3247
3248         DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3249         return retval;
3250 }
3251
3252 /*
3253  * allocate buffers used for calling line discipline receive_buf
3254  * directly in synchronous mode
3255  * note: add 5 bytes to max frame size to allow appending
3256  * 32-bit CRC and status byte when configured to do so
3257  */
3258 static int alloc_tmp_rbuf(struct slgt_info *info)
3259 {
3260         info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3261         if (info->tmp_rbuf == NULL)
3262                 return -ENOMEM;
3263         /* unused flag buffer to satisfy receive_buf calling interface */
3264         info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3265         if (!info->flag_buf) {
3266                 kfree(info->tmp_rbuf);
3267                 info->tmp_rbuf = NULL;
3268                 return -ENOMEM;
3269         }
3270         return 0;
3271 }
3272
3273 static void free_tmp_rbuf(struct slgt_info *info)
3274 {
3275         kfree(info->tmp_rbuf);
3276         info->tmp_rbuf = NULL;
3277         kfree(info->flag_buf);
3278         info->flag_buf = NULL;
3279 }
3280
3281 /*
3282  * allocate DMA descriptor lists.
3283  */
3284 static int alloc_desc(struct slgt_info *info)
3285 {
3286         unsigned int i;
3287         unsigned int pbufs;
3288
3289         /* allocate memory to hold descriptor lists */
3290         info->bufs = pci_zalloc_consistent(info->pdev, DESC_LIST_SIZE,
3291                                            &info->bufs_dma_addr);
3292         if (info->bufs == NULL)
3293                 return -ENOMEM;
3294
3295         info->rbufs = (struct slgt_desc*)info->bufs;
3296         info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3297
3298         pbufs = (unsigned int)info->bufs_dma_addr;
3299
3300         /*
3301          * Build circular lists of descriptors
3302          */
3303
3304         for (i=0; i < info->rbuf_count; i++) {
3305                 /* physical address of this descriptor */
3306                 info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3307
3308                 /* physical address of next descriptor */
3309                 if (i == info->rbuf_count - 1)
3310                         info->rbufs[i].next = cpu_to_le32(pbufs);
3311                 else
3312                         info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3313                 set_desc_count(info->rbufs[i], DMABUFSIZE);
3314         }
3315
3316         for (i=0; i < info->tbuf_count; i++) {
3317                 /* physical address of this descriptor */
3318                 info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3319
3320                 /* physical address of next descriptor */
3321                 if (i == info->tbuf_count - 1)
3322                         info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3323                 else
3324                         info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3325         }
3326
3327         return 0;
3328 }
3329
3330 static void free_desc(struct slgt_info *info)
3331 {
3332         if (info->bufs != NULL) {
3333                 pci_free_consistent(info->pdev, DESC_LIST_SIZE, info->bufs, info->bufs_dma_addr);
3334                 info->bufs  = NULL;
3335                 info->rbufs = NULL;
3336                 info->tbufs = NULL;
3337         }
3338 }
3339
3340 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3341 {
3342         int i;
3343         for (i=0; i < count; i++) {
3344                 if ((bufs[i].buf = pci_alloc_consistent(info->pdev, DMABUFSIZE, &bufs[i].buf_dma_addr)) == NULL)
3345                         return -ENOMEM;
3346                 bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3347         }
3348         return 0;
3349 }
3350
3351 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3352 {
3353         int i;
3354         for (i=0; i < count; i++) {
3355                 if (bufs[i].buf == NULL)
3356                         continue;
3357                 pci_free_consistent(info->pdev, DMABUFSIZE, bufs[i].buf, bufs[i].buf_dma_addr);
3358                 bufs[i].buf = NULL;
3359         }
3360 }
3361
3362 static int alloc_dma_bufs(struct slgt_info *info)
3363 {
3364         info->rbuf_count = 32;
3365         info->tbuf_count = 32;
3366
3367         if (alloc_desc(info) < 0 ||
3368             alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3369             alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3370             alloc_tmp_rbuf(info) < 0) {
3371                 DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3372                 return -ENOMEM;
3373         }
3374         reset_rbufs(info);
3375         return 0;
3376 }
3377
3378 static void free_dma_bufs(struct slgt_info *info)
3379 {
3380         if (info->bufs) {
3381                 free_bufs(info, info->rbufs, info->rbuf_count);
3382                 free_bufs(info, info->tbufs, info->tbuf_count);
3383                 free_desc(info);
3384         }
3385         free_tmp_rbuf(info);
3386 }
3387
3388 static int claim_resources(struct slgt_info *info)
3389 {
3390         if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3391                 DBGERR(("%s reg addr conflict, addr=%08X\n",
3392                         info->device_name, info->phys_reg_addr));
3393                 info->init_error = DiagStatus_AddressConflict;
3394                 goto errout;
3395         }
3396         else
3397                 info->reg_addr_requested = true;
3398
3399         info->reg_addr = ioremap_nocache(info->phys_reg_addr, SLGT_REG_SIZE);
3400         if (!info->reg_addr) {
3401                 DBGERR(("%s can't map device registers, addr=%08X\n",
3402                         info->device_name, info->phys_reg_addr));
3403                 info->init_error = DiagStatus_CantAssignPciResources;
3404                 goto errout;
3405         }
3406         return 0;
3407
3408 errout:
3409         release_resources(info);
3410         return -ENODEV;
3411 }
3412
3413 static void release_resources(struct slgt_info *info)
3414 {
3415         if (info->irq_requested) {
3416                 free_irq(info->irq_level, info);
3417                 info->irq_requested = false;
3418         }
3419
3420         if (info->reg_addr_requested) {
3421                 release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3422                 info->reg_addr_requested = false;
3423         }
3424
3425         if (info->reg_addr) {
3426                 iounmap(info->reg_addr);
3427                 info->reg_addr = NULL;
3428         }
3429 }
3430
3431 /* Add the specified device instance data structure to the
3432  * global linked list of devices and increment the device count.
3433  */
3434 static void add_device(struct slgt_info *info)
3435 {
3436         char *devstr;
3437
3438         info->next_device = NULL;
3439         info->line = slgt_device_count;
3440         sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3441
3442         if (info->line < MAX_DEVICES) {
3443                 if (maxframe[info->line])
3444                         info->max_frame_size = maxframe[info->line];
3445         }
3446
3447         slgt_device_count++;
3448
3449         if (!slgt_device_list)
3450                 slgt_device_list = info;
3451         else {
3452                 struct slgt_info *current_dev = slgt_device_list;
3453                 while(current_dev->next_device)
3454                         current_dev = current_dev->next_device;
3455                 current_dev->next_device = info;
3456         }
3457
3458         if (info->max_frame_size < 4096)
3459                 info->max_frame_size = 4096;
3460         else if (info->max_frame_size > 65535)
3461                 info->max_frame_size = 65535;
3462
3463         switch(info->pdev->device) {
3464         case SYNCLINK_GT_DEVICE_ID:
3465                 devstr = "GT";
3466                 break;
3467         case SYNCLINK_GT2_DEVICE_ID:
3468                 devstr = "GT2";
3469                 break;
3470         case SYNCLINK_GT4_DEVICE_ID:
3471                 devstr = "GT4";
3472                 break;
3473         case SYNCLINK_AC_DEVICE_ID:
3474                 devstr = "AC";
3475                 info->params.mode = MGSL_MODE_ASYNC;
3476                 break;
3477         default:
3478                 devstr = "(unknown model)";
3479         }
3480         printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3481                 devstr, info->device_name, info->phys_reg_addr,
3482                 info->irq_level, info->max_frame_size);
3483
3484 #if SYNCLINK_GENERIC_HDLC
3485         hdlcdev_init(info);
3486 #endif
3487 }
3488
3489 static const struct tty_port_operations slgt_port_ops = {
3490         .carrier_raised = carrier_raised,
3491         .dtr_rts = dtr_rts,
3492 };
3493
3494 /*
3495  *  allocate device instance structure, return NULL on failure
3496  */
3497 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3498 {
3499         struct slgt_info *info;
3500
3501         info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3502
3503         if (!info) {
3504                 DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3505                         driver_name, adapter_num, port_num));
3506         } else {
3507                 tty_port_init(&info->port);
3508                 info->port.ops = &slgt_port_ops;
3509                 info->magic = MGSL_MAGIC;
3510                 INIT_WORK(&info->task, bh_handler);
3511                 info->max_frame_size = 4096;
3512                 info->base_clock = 14745600;
3513                 info->rbuf_fill_level = DMABUFSIZE;
3514                 info->port.close_delay = 5*HZ/10;
3515                 info->port.closing_wait = 30*HZ;
3516                 init_waitqueue_head(&info->status_event_wait_q);
3517                 init_waitqueue_head(&info->event_wait_q);
3518                 spin_lock_init(&info->netlock);
3519                 memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3520                 info->idle_mode = HDLC_TXIDLE_FLAGS;
3521                 info->adapter_num = adapter_num;
3522                 info->port_num = port_num;
3523
3524                 timer_setup(&info->tx_timer, tx_timeout, 0);
3525                 timer_setup(&info->rx_timer, rx_timeout, 0);
3526
3527                 /* Copy configuration info to device instance data */
3528                 info->pdev = pdev;
3529                 info->irq_level = pdev->irq;
3530                 info->phys_reg_addr = pci_resource_start(pdev,0);
3531
3532                 info->bus_type = MGSL_BUS_TYPE_PCI;
3533                 info->irq_flags = IRQF_SHARED;
3534
3535                 info->init_error = -1; /* assume error, set to 0 on successful init */
3536         }
3537
3538         return info;
3539 }
3540
3541 static void device_init(int adapter_num, struct pci_dev *pdev)
3542 {
3543         struct slgt_info *port_array[SLGT_MAX_PORTS];
3544         int i;
3545         int port_count = 1;
3546
3547         if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3548                 port_count = 2;
3549         else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3550                 port_count = 4;
3551
3552         /* allocate device instances for all ports */
3553         for (i=0; i < port_count; ++i) {
3554                 port_array[i] = alloc_dev(adapter_num, i, pdev);
3555                 if (port_array[i] == NULL) {
3556                         for (--i; i >= 0; --i) {
3557                                 tty_port_destroy(&port_array[i]->port);
3558                                 kfree(port_array[i]);
3559                         }
3560                         return;
3561                 }
3562         }
3563
3564         /* give copy of port_array to all ports and add to device list  */
3565         for (i=0; i < port_count; ++i) {
3566                 memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3567                 add_device(port_array[i]);
3568                 port_array[i]->port_count = port_count;
3569                 spin_lock_init(&port_array[i]->lock);
3570         }
3571
3572         /* Allocate and claim adapter resources */
3573         if (!claim_resources(port_array[0])) {
3574
3575                 alloc_dma_bufs(port_array[0]);
3576
3577                 /* copy resource information from first port to others */
3578                 for (i = 1; i < port_count; ++i) {
3579                         port_array[i]->irq_level = port_array[0]->irq_level;
3580                         port_array[i]->reg_addr  = port_array[0]->reg_addr;
3581                         alloc_dma_bufs(port_array[i]);
3582                 }
3583
3584                 if (request_irq(port_array[0]->irq_level,
3585                                         slgt_interrupt,
3586                                         port_array[0]->irq_flags,
3587                                         port_array[0]->device_name,
3588                                         port_array[0]) < 0) {
3589                         DBGERR(("%s request_irq failed IRQ=%d\n",
3590                                 port_array[0]->device_name,
3591                                 port_array[0]->irq_level));
3592                 } else {
3593                         port_array[0]->irq_requested = true;
3594                         adapter_test(port_array[0]);
3595                         for (i=1 ; i < port_count ; i++) {
3596                                 port_array[i]->init_error = port_array[0]->init_error;
3597                                 port_array[i]->gpio_present = port_array[0]->gpio_present;
3598                         }
3599                 }
3600         }
3601
3602         for (i = 0; i < port_count; ++i) {
3603                 struct slgt_info *info = port_array[i];
3604                 tty_port_register_device(&info->port, serial_driver, info->line,
3605                                 &info->pdev->dev);
3606         }
3607 }
3608
3609 static int init_one(struct pci_dev *dev,
3610                               const struct pci_device_id *ent)
3611 {
3612         if (pci_enable_device(dev)) {
3613                 printk("error enabling pci device %p\n", dev);
3614                 return -EIO;
3615         }
3616         pci_set_master(dev);
3617         device_init(slgt_device_count, dev);
3618         return 0;
3619 }
3620
3621 static void remove_one(struct pci_dev *dev)
3622 {
3623 }
3624
3625 static const struct tty_operations ops = {
3626         .open = open,
3627         .close = close,
3628         .write = write,
3629         .put_char = put_char,
3630         .flush_chars = flush_chars,
3631         .write_room = write_room,
3632         .chars_in_buffer = chars_in_buffer,
3633         .flush_buffer = flush_buffer,
3634         .ioctl = ioctl,
3635         .compat_ioctl = slgt_compat_ioctl,
3636         .throttle = throttle,
3637         .unthrottle = unthrottle,
3638         .send_xchar = send_xchar,
3639         .break_ctl = set_break,
3640         .wait_until_sent = wait_until_sent,
3641         .set_termios = set_termios,
3642         .stop = tx_hold,
3643         .start = tx_release,
3644         .hangup = hangup,
3645         .tiocmget = tiocmget,
3646         .tiocmset = tiocmset,
3647         .get_icount = get_icount,
3648         .proc_show = synclink_gt_proc_show,
3649 };
3650
3651 static void slgt_cleanup(void)
3652 {
3653         int rc;
3654         struct slgt_info *info;
3655         struct slgt_info *tmp;
3656
3657         printk(KERN_INFO "unload %s\n", driver_name);
3658
3659         if (serial_driver) {
3660                 for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3661                         tty_unregister_device(serial_driver, info->line);
3662                 rc = tty_unregister_driver(serial_driver);
3663                 if (rc)
3664                         DBGERR(("tty_unregister_driver error=%d\n", rc));
3665                 put_tty_driver(serial_driver);
3666         }
3667
3668         /* reset devices */
3669         info = slgt_device_list;
3670         while(info) {
3671                 reset_port(info);
3672                 info = info->next_device;
3673         }
3674
3675         /* release devices */
3676         info = slgt_device_list;
3677         while(info) {
3678 #if SYNCLINK_GENERIC_HDLC
3679                 hdlcdev_exit(info);
3680 #endif
3681                 free_dma_bufs(info);
3682                 free_tmp_rbuf(info);
3683                 if (info->port_num == 0)
3684                         release_resources(info);
3685                 tmp = info;
3686                 info = info->next_device;
3687                 tty_port_destroy(&tmp->port);
3688                 kfree(tmp);
3689         }
3690
3691         if (pci_registered)
3692                 pci_unregister_driver(&pci_driver);
3693 }
3694
3695 /*
3696  *  Driver initialization entry point.
3697  */
3698 static int __init slgt_init(void)
3699 {
3700         int rc;
3701
3702         printk(KERN_INFO "%s\n", driver_name);
3703
3704         serial_driver = alloc_tty_driver(MAX_DEVICES);
3705         if (!serial_driver) {
3706                 printk("%s can't allocate tty driver\n", driver_name);
3707                 return -ENOMEM;
3708         }
3709
3710         /* Initialize the tty_driver structure */
3711
3712         serial_driver->driver_name = slgt_driver_name;
3713         serial_driver->name = tty_dev_prefix;
3714         serial_driver->major = ttymajor;
3715         serial_driver->minor_start = 64;
3716         serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3717         serial_driver->subtype = SERIAL_TYPE_NORMAL;
3718         serial_driver->init_termios = tty_std_termios;
3719         serial_driver->init_termios.c_cflag =
3720                 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3721         serial_driver->init_termios.c_ispeed = 9600;
3722         serial_driver->init_termios.c_ospeed = 9600;
3723         serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
3724         tty_set_operations(serial_driver, &ops);
3725         if ((rc = tty_register_driver(serial_driver)) < 0) {
3726                 DBGERR(("%s can't register serial driver\n", driver_name));
3727                 put_tty_driver(serial_driver);
3728                 serial_driver = NULL;
3729                 goto error;
3730         }
3731
3732         printk(KERN_INFO "%s, tty major#%d\n",
3733                driver_name, serial_driver->major);
3734
3735         slgt_device_count = 0;
3736         if ((rc = pci_register_driver(&pci_driver)) < 0) {
3737                 printk("%s pci_register_driver error=%d\n", driver_name, rc);
3738                 goto error;
3739         }
3740         pci_registered = true;
3741
3742         if (!slgt_device_list)
3743                 printk("%s no devices found\n",driver_name);
3744
3745         return 0;
3746
3747 error:
3748         slgt_cleanup();
3749         return rc;
3750 }
3751
3752 static void __exit slgt_exit(void)
3753 {
3754         slgt_cleanup();
3755 }
3756
3757 module_init(slgt_init);
3758 module_exit(slgt_exit);
3759
3760 /*
3761  * register access routines
3762  */
3763
3764 #define CALC_REGADDR() \
3765         unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3766         if (addr >= 0x80) \
3767                 reg_addr += (info->port_num) * 32; \
3768         else if (addr >= 0x40)  \
3769                 reg_addr += (info->port_num) * 16;
3770
3771 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3772 {
3773         CALC_REGADDR();
3774         return readb((void __iomem *)reg_addr);
3775 }
3776
3777 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3778 {
3779         CALC_REGADDR();
3780         writeb(value, (void __iomem *)reg_addr);
3781 }
3782
3783 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3784 {
3785         CALC_REGADDR();
3786         return readw((void __iomem *)reg_addr);
3787 }
3788
3789 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3790 {
3791         CALC_REGADDR();
3792         writew(value, (void __iomem *)reg_addr);
3793 }
3794
3795 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3796 {
3797         CALC_REGADDR();
3798         return readl((void __iomem *)reg_addr);
3799 }
3800
3801 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3802 {
3803         CALC_REGADDR();
3804         writel(value, (void __iomem *)reg_addr);
3805 }
3806
3807 static void rdma_reset(struct slgt_info *info)
3808 {
3809         unsigned int i;
3810
3811         /* set reset bit */
3812         wr_reg32(info, RDCSR, BIT1);
3813
3814         /* wait for enable bit cleared */
3815         for(i=0 ; i < 1000 ; i++)
3816                 if (!(rd_reg32(info, RDCSR) & BIT0))
3817                         break;
3818 }
3819
3820 static void tdma_reset(struct slgt_info *info)
3821 {
3822         unsigned int i;
3823
3824         /* set reset bit */
3825         wr_reg32(info, TDCSR, BIT1);
3826
3827         /* wait for enable bit cleared */
3828         for(i=0 ; i < 1000 ; i++)
3829                 if (!(rd_reg32(info, TDCSR) & BIT0))
3830                         break;
3831 }
3832
3833 /*
3834  * enable internal loopback
3835  * TxCLK and RxCLK are generated from BRG
3836  * and TxD is looped back to RxD internally.
3837  */
3838 static void enable_loopback(struct slgt_info *info)
3839 {
3840         /* SCR (serial control) BIT2=loopback enable */
3841         wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3842
3843         if (info->params.mode != MGSL_MODE_ASYNC) {
3844                 /* CCR (clock control)
3845                  * 07..05  tx clock source (010 = BRG)
3846                  * 04..02  rx clock source (010 = BRG)
3847                  * 01      auxclk enable   (0 = disable)
3848                  * 00      BRG enable      (1 = enable)
3849                  *
3850                  * 0100 1001
3851                  */
3852                 wr_reg8(info, CCR, 0x49);
3853
3854                 /* set speed if available, otherwise use default */
3855                 if (info->params.clock_speed)
3856                         set_rate(info, info->params.clock_speed);
3857                 else
3858                         set_rate(info, 3686400);
3859         }
3860 }
3861
3862 /*
3863  *  set baud rate generator to specified rate
3864  */
3865 static void set_rate(struct slgt_info *info, u32 rate)
3866 {
3867         unsigned int div;
3868         unsigned int osc = info->base_clock;
3869
3870         /* div = osc/rate - 1
3871          *
3872          * Round div up if osc/rate is not integer to
3873          * force to next slowest rate.
3874          */
3875
3876         if (rate) {
3877                 div = osc/rate;
3878                 if (!(osc % rate) && div)
3879                         div--;
3880                 wr_reg16(info, BDR, (unsigned short)div);
3881         }
3882 }
3883
3884 static void rx_stop(struct slgt_info *info)
3885 {
3886         unsigned short val;
3887
3888         /* disable and reset receiver */
3889         val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3890         wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3891         wr_reg16(info, RCR, val);                  /* clear reset bit */
3892
3893         slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3894
3895         /* clear pending rx interrupts */
3896         wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3897
3898         rdma_reset(info);
3899
3900         info->rx_enabled = false;
3901         info->rx_restart = false;
3902 }
3903
3904 static void rx_start(struct slgt_info *info)
3905 {
3906         unsigned short val;
3907
3908         slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3909
3910         /* clear pending rx overrun IRQ */
3911         wr_reg16(info, SSR, IRQ_RXOVER);
3912
3913         /* reset and disable receiver */
3914         val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3915         wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3916         wr_reg16(info, RCR, val);                  /* clear reset bit */
3917
3918         rdma_reset(info);
3919         reset_rbufs(info);
3920
3921         if (info->rx_pio) {
3922                 /* rx request when rx FIFO not empty */
3923                 wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
3924                 slgt_irq_on(info, IRQ_RXDATA);
3925                 if (info->params.mode == MGSL_MODE_ASYNC) {
3926                         /* enable saving of rx status */
3927                         wr_reg32(info, RDCSR, BIT6);
3928                 }
3929         } else {
3930                 /* rx request when rx FIFO half full */
3931                 wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
3932                 /* set 1st descriptor address */
3933                 wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
3934
3935                 if (info->params.mode != MGSL_MODE_ASYNC) {
3936                         /* enable rx DMA and DMA interrupt */
3937                         wr_reg32(info, RDCSR, (BIT2 + BIT0));
3938                 } else {
3939                         /* enable saving of rx status, rx DMA and DMA interrupt */
3940                         wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
3941                 }
3942         }
3943
3944         slgt_irq_on(info, IRQ_RXOVER);
3945
3946         /* enable receiver */
3947         wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
3948
3949         info->rx_restart = false;
3950         info->rx_enabled = true;
3951 }
3952
3953 static void tx_start(struct slgt_info *info)
3954 {
3955         if (!info->tx_enabled) {
3956                 wr_reg16(info, TCR,
3957                          (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
3958                 info->tx_enabled = true;
3959         }
3960
3961         if (desc_count(info->tbufs[info->tbuf_start])) {
3962                 info->drop_rts_on_tx_done = false;
3963
3964                 if (info->params.mode != MGSL_MODE_ASYNC) {
3965                         if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
3966                                 get_gtsignals(info);
3967                                 if (!(info->signals & SerialSignal_RTS)) {
3968                                         info->signals |= SerialSignal_RTS;
3969                                         set_gtsignals(info);
3970                                         info->drop_rts_on_tx_done = true;
3971                                 }
3972                         }
3973
3974                         slgt_irq_off(info, IRQ_TXDATA);
3975                         slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
3976                         /* clear tx idle and underrun status bits */
3977                         wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3978                 } else {
3979                         slgt_irq_off(info, IRQ_TXDATA);
3980                         slgt_irq_on(info, IRQ_TXIDLE);
3981                         /* clear tx idle status bit */
3982                         wr_reg16(info, SSR, IRQ_TXIDLE);
3983                 }
3984                 /* set 1st descriptor address and start DMA */
3985                 wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
3986                 wr_reg32(info, TDCSR, BIT2 + BIT0);
3987                 info->tx_active = true;
3988         }
3989 }
3990
3991 static void tx_stop(struct slgt_info *info)
3992 {
3993         unsigned short val;
3994
3995         del_timer(&info->tx_timer);
3996
3997         tdma_reset(info);
3998
3999         /* reset and disable transmitter */
4000         val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
4001         wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
4002
4003         slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
4004
4005         /* clear tx idle and underrun status bit */
4006         wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4007
4008         reset_tbufs(info);
4009
4010         info->tx_enabled = false;
4011         info->tx_active = false;
4012 }
4013
4014 static void reset_port(struct slgt_info *info)
4015 {
4016         if (!info->reg_addr)
4017                 return;
4018
4019         tx_stop(info);
4020         rx_stop(info);
4021
4022         info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4023         set_gtsignals(info);
4024
4025         slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4026 }
4027
4028 static void reset_adapter(struct slgt_info *info)
4029 {
4030         int i;
4031         for (i=0; i < info->port_count; ++i) {
4032                 if (info->port_array[i])
4033                         reset_port(info->port_array[i]);
4034         }
4035 }
4036
4037 static void async_mode(struct slgt_info *info)
4038 {
4039         unsigned short val;
4040
4041         slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4042         tx_stop(info);
4043         rx_stop(info);
4044
4045         /* TCR (tx control)
4046          *
4047          * 15..13  mode, 010=async
4048          * 12..10  encoding, 000=NRZ
4049          * 09      parity enable
4050          * 08      1=odd parity, 0=even parity
4051          * 07      1=RTS driver control
4052          * 06      1=break enable
4053          * 05..04  character length
4054          *         00=5 bits
4055          *         01=6 bits
4056          *         10=7 bits
4057          *         11=8 bits
4058          * 03      0=1 stop bit, 1=2 stop bits
4059          * 02      reset
4060          * 01      enable
4061          * 00      auto-CTS enable
4062          */
4063         val = 0x4000;
4064
4065         if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4066                 val |= BIT7;
4067
4068         if (info->params.parity != ASYNC_PARITY_NONE) {
4069                 val |= BIT9;
4070                 if (info->params.parity == ASYNC_PARITY_ODD)
4071                         val |= BIT8;
4072         }
4073
4074         switch (info->params.data_bits)
4075         {
4076         case 6: val |= BIT4; break;
4077         case 7: val |= BIT5; break;
4078         case 8: val |= BIT5 + BIT4; break;
4079         }
4080
4081         if (info->params.stop_bits != 1)
4082                 val |= BIT3;
4083
4084         if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4085                 val |= BIT0;
4086
4087         wr_reg16(info, TCR, val);
4088
4089         /* RCR (rx control)
4090          *
4091          * 15..13  mode, 010=async
4092          * 12..10  encoding, 000=NRZ
4093          * 09      parity enable
4094          * 08      1=odd parity, 0=even parity
4095          * 07..06  reserved, must be 0
4096          * 05..04  character length
4097          *         00=5 bits
4098          *         01=6 bits
4099          *         10=7 bits
4100          *         11=8 bits
4101          * 03      reserved, must be zero
4102          * 02      reset
4103          * 01      enable
4104          * 00      auto-DCD enable
4105          */
4106         val = 0x4000;
4107
4108         if (info->params.parity != ASYNC_PARITY_NONE) {
4109                 val |= BIT9;
4110                 if (info->params.parity == ASYNC_PARITY_ODD)
4111                         val |= BIT8;
4112         }
4113
4114         switch (info->params.data_bits)
4115         {
4116         case 6: val |= BIT4; break;
4117         case 7: val |= BIT5; break;
4118         case 8: val |= BIT5 + BIT4; break;
4119         }
4120
4121         if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4122                 val |= BIT0;
4123
4124         wr_reg16(info, RCR, val);
4125
4126         /* CCR (clock control)
4127          *
4128          * 07..05  011 = tx clock source is BRG/16
4129          * 04..02  010 = rx clock source is BRG
4130          * 01      0 = auxclk disabled
4131          * 00      1 = BRG enabled
4132          *
4133          * 0110 1001
4134          */
4135         wr_reg8(info, CCR, 0x69);
4136
4137         msc_set_vcr(info);
4138
4139         /* SCR (serial control)
4140          *
4141          * 15  1=tx req on FIFO half empty
4142          * 14  1=rx req on FIFO half full
4143          * 13  tx data  IRQ enable
4144          * 12  tx idle  IRQ enable
4145          * 11  rx break on IRQ enable
4146          * 10  rx data  IRQ enable
4147          * 09  rx break off IRQ enable
4148          * 08  overrun  IRQ enable
4149          * 07  DSR      IRQ enable
4150          * 06  CTS      IRQ enable
4151          * 05  DCD      IRQ enable
4152          * 04  RI       IRQ enable
4153          * 03  0=16x sampling, 1=8x sampling
4154          * 02  1=txd->rxd internal loopback enable
4155          * 01  reserved, must be zero
4156          * 00  1=master IRQ enable
4157          */
4158         val = BIT15 + BIT14 + BIT0;
4159         /* JCR[8] : 1 = x8 async mode feature available */
4160         if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4161             ((info->base_clock < (info->params.data_rate * 16)) ||
4162              (info->base_clock % (info->params.data_rate * 16)))) {
4163                 /* use 8x sampling */
4164                 val |= BIT3;
4165                 set_rate(info, info->params.data_rate * 8);
4166         } else {
4167                 /* use 16x sampling */
4168                 set_rate(info, info->params.data_rate * 16);
4169         }
4170         wr_reg16(info, SCR, val);
4171
4172         slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4173
4174         if (info->params.loopback)
4175                 enable_loopback(info);
4176 }
4177
4178 static void sync_mode(struct slgt_info *info)
4179 {
4180         unsigned short val;
4181
4182         slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4183         tx_stop(info);
4184         rx_stop(info);
4185
4186         /* TCR (tx control)
4187          *
4188          * 15..13  mode
4189          *         000=HDLC/SDLC
4190          *         001=raw bit synchronous
4191          *         010=asynchronous/isochronous
4192          *         011=monosync byte synchronous
4193          *         100=bisync byte synchronous
4194          *         101=xsync byte synchronous
4195          * 12..10  encoding
4196          * 09      CRC enable
4197          * 08      CRC32
4198          * 07      1=RTS driver control
4199          * 06      preamble enable
4200          * 05..04  preamble length
4201          * 03      share open/close flag
4202          * 02      reset
4203          * 01      enable
4204          * 00      auto-CTS enable
4205          */
4206         val = BIT2;
4207
4208         switch(info->params.mode) {
4209         case MGSL_MODE_XSYNC:
4210                 val |= BIT15 + BIT13;
4211                 break;
4212         case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4213         case MGSL_MODE_BISYNC:   val |= BIT15; break;
4214         case MGSL_MODE_RAW:      val |= BIT13; break;
4215         }
4216         if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4217                 val |= BIT7;
4218
4219         switch(info->params.encoding)
4220         {
4221         case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4222         case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4223         case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4224         case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4225         case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4226         case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4227         case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4228         }
4229
4230         switch (info->params.crc_type & HDLC_CRC_MASK)
4231         {
4232         case HDLC_CRC_16_CCITT: val |= BIT9; break;
4233         case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4234         }
4235
4236         if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4237                 val |= BIT6;
4238
4239         switch (info->params.preamble_length)
4240         {
4241         case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4242         case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4243         case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4244         }
4245
4246         if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4247                 val |= BIT0;
4248
4249         wr_reg16(info, TCR, val);
4250
4251         /* TPR (transmit preamble) */
4252
4253         switch (info->params.preamble)
4254         {
4255         case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4256         case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4257         case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4258         case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4259         case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4260         default:                          val = 0x7e; break;
4261         }
4262         wr_reg8(info, TPR, (unsigned char)val);
4263
4264         /* RCR (rx control)
4265          *
4266          * 15..13  mode
4267          *         000=HDLC/SDLC
4268          *         001=raw bit synchronous
4269          *         010=asynchronous/isochronous
4270          *         011=monosync byte synchronous
4271          *         100=bisync byte synchronous
4272          *         101=xsync byte synchronous
4273          * 12..10  encoding
4274          * 09      CRC enable
4275          * 08      CRC32
4276          * 07..03  reserved, must be 0
4277          * 02      reset
4278          * 01      enable
4279          * 00      auto-DCD enable
4280          */
4281         val = 0;
4282
4283         switch(info->params.mode) {
4284         case MGSL_MODE_XSYNC:
4285                 val |= BIT15 + BIT13;
4286                 break;
4287         case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4288         case MGSL_MODE_BISYNC:   val |= BIT15; break;
4289         case MGSL_MODE_RAW:      val |= BIT13; break;
4290         }
4291
4292         switch(info->params.encoding)
4293         {
4294         case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4295         case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4296         case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4297         case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4298         case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4299         case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4300         case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4301         }
4302
4303         switch (info->params.crc_type & HDLC_CRC_MASK)
4304         {
4305         case HDLC_CRC_16_CCITT: val |= BIT9; break;
4306         case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4307         }
4308
4309         if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4310                 val |= BIT0;
4311
4312         wr_reg16(info, RCR, val);
4313
4314         /* CCR (clock control)
4315          *
4316          * 07..05  tx clock source
4317          * 04..02  rx clock source
4318          * 01      auxclk enable
4319          * 00      BRG enable
4320          */
4321         val = 0;
4322
4323         if (info->params.flags & HDLC_FLAG_TXC_BRG)
4324         {
4325                 // when RxC source is DPLL, BRG generates 16X DPLL
4326                 // reference clock, so take TxC from BRG/16 to get
4327                 // transmit clock at actual data rate
4328                 if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4329                         val |= BIT6 + BIT5;     /* 011, txclk = BRG/16 */
4330                 else
4331                         val |= BIT6;    /* 010, txclk = BRG */
4332         }
4333         else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4334                 val |= BIT7;    /* 100, txclk = DPLL Input */
4335         else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4336                 val |= BIT5;    /* 001, txclk = RXC Input */
4337
4338         if (info->params.flags & HDLC_FLAG_RXC_BRG)
4339                 val |= BIT3;    /* 010, rxclk = BRG */
4340         else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4341                 val |= BIT4;    /* 100, rxclk = DPLL */
4342         else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4343                 val |= BIT2;    /* 001, rxclk = TXC Input */
4344
4345         if (info->params.clock_speed)
4346                 val |= BIT1 + BIT0;
4347
4348         wr_reg8(info, CCR, (unsigned char)val);
4349
4350         if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4351         {
4352                 // program DPLL mode
4353                 switch(info->params.encoding)
4354                 {
4355                 case HDLC_ENCODING_BIPHASE_MARK:
4356                 case HDLC_ENCODING_BIPHASE_SPACE:
4357                         val = BIT7; break;
4358                 case HDLC_ENCODING_BIPHASE_LEVEL:
4359                 case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4360                         val = BIT7 + BIT6; break;
4361                 default: val = BIT6;    // NRZ encodings
4362                 }
4363                 wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4364
4365                 // DPLL requires a 16X reference clock from BRG
4366                 set_rate(info, info->params.clock_speed * 16);
4367         }
4368         else
4369                 set_rate(info, info->params.clock_speed);
4370
4371         tx_set_idle(info);
4372
4373         msc_set_vcr(info);
4374
4375         /* SCR (serial control)
4376          *
4377          * 15  1=tx req on FIFO half empty
4378          * 14  1=rx req on FIFO half full
4379          * 13  tx data  IRQ enable
4380          * 12  tx idle  IRQ enable
4381          * 11  underrun IRQ enable
4382          * 10  rx data  IRQ enable
4383          * 09  rx idle  IRQ enable
4384          * 08  overrun  IRQ enable
4385          * 07  DSR      IRQ enable
4386          * 06  CTS      IRQ enable
4387          * 05  DCD      IRQ enable
4388          * 04  RI       IRQ enable
4389          * 03  reserved, must be zero
4390          * 02  1=txd->rxd internal loopback enable
4391          * 01  reserved, must be zero
4392          * 00  1=master IRQ enable
4393          */
4394         wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4395
4396         if (info->params.loopback)
4397                 enable_loopback(info);
4398 }
4399
4400 /*
4401  *  set transmit idle mode
4402  */
4403 static void tx_set_idle(struct slgt_info *info)
4404 {
4405         unsigned char val;
4406         unsigned short tcr;
4407
4408         /* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4409          * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4410          */
4411         tcr = rd_reg16(info, TCR);
4412         if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4413                 /* disable preamble, set idle size to 16 bits */
4414                 tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4415                 /* MSB of 16 bit idle specified in tx preamble register (TPR) */
4416                 wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4417         } else if (!(tcr & BIT6)) {
4418                 /* preamble is disabled, set idle size to 8 bits */
4419                 tcr &= ~(BIT5 + BIT4);
4420         }
4421         wr_reg16(info, TCR, tcr);
4422
4423         if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4424                 /* LSB of custom tx idle specified in tx idle register */
4425                 val = (unsigned char)(info->idle_mode & 0xff);
4426         } else {
4427                 /* standard 8 bit idle patterns */
4428                 switch(info->idle_mode)
4429                 {
4430                 case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4431                 case HDLC_TXIDLE_ALT_ZEROS_ONES:
4432                 case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4433                 case HDLC_TXIDLE_ZEROS:
4434                 case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4435                 default:                         val = 0xff;
4436                 }
4437         }
4438
4439         wr_reg8(info, TIR, val);
4440 }
4441
4442 /*
4443  * get state of V24 status (input) signals
4444  */
4445 static void get_gtsignals(struct slgt_info *info)
4446 {
4447         unsigned short status = rd_reg16(info, SSR);
4448
4449         /* clear all serial signals except RTS and DTR */
4450         info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4451
4452         if (status & BIT3)
4453                 info->signals |= SerialSignal_DSR;
4454         if (status & BIT2)
4455                 info->signals |= SerialSignal_CTS;
4456         if (status & BIT1)
4457                 info->signals |= SerialSignal_DCD;
4458         if (status & BIT0)
4459                 info->signals |= SerialSignal_RI;
4460 }
4461
4462 /*
4463  * set V.24 Control Register based on current configuration
4464  */
4465 static void msc_set_vcr(struct slgt_info *info)
4466 {
4467         unsigned char val = 0;
4468
4469         /* VCR (V.24 control)
4470          *
4471          * 07..04  serial IF select
4472          * 03      DTR
4473          * 02      RTS
4474          * 01      LL
4475          * 00      RL
4476          */
4477
4478         switch(info->if_mode & MGSL_INTERFACE_MASK)
4479         {
4480         case MGSL_INTERFACE_RS232:
4481                 val |= BIT5; /* 0010 */
4482                 break;
4483         case MGSL_INTERFACE_V35:
4484                 val |= BIT7 + BIT6 + BIT5; /* 1110 */
4485                 break;
4486         case MGSL_INTERFACE_RS422:
4487                 val |= BIT6; /* 0100 */
4488                 break;
4489         }
4490
4491         if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4492                 val |= BIT4;
4493         if (info->signals & SerialSignal_DTR)
4494                 val |= BIT3;
4495         if (info->signals & SerialSignal_RTS)
4496                 val |= BIT2;
4497         if (info->if_mode & MGSL_INTERFACE_LL)
4498                 val |= BIT1;
4499         if (info->if_mode & MGSL_INTERFACE_RL)
4500                 val |= BIT0;
4501         wr_reg8(info, VCR, val);
4502 }
4503
4504 /*
4505  * set state of V24 control (output) signals
4506  */
4507 static void set_gtsignals(struct slgt_info *info)
4508 {
4509         unsigned char val = rd_reg8(info, VCR);
4510         if (info->signals & SerialSignal_DTR)
4511                 val |= BIT3;
4512         else
4513                 val &= ~BIT3;
4514         if (info->signals & SerialSignal_RTS)
4515                 val |= BIT2;
4516         else
4517                 val &= ~BIT2;
4518         wr_reg8(info, VCR, val);
4519 }
4520
4521 /*
4522  * free range of receive DMA buffers (i to last)
4523  */
4524 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4525 {
4526         int done = 0;
4527
4528         while(!done) {
4529                 /* reset current buffer for reuse */
4530                 info->rbufs[i].status = 0;
4531                 set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4532                 if (i == last)
4533                         done = 1;
4534                 if (++i == info->rbuf_count)
4535                         i = 0;
4536         }
4537         info->rbuf_current = i;
4538 }
4539
4540 /*
4541  * mark all receive DMA buffers as free
4542  */
4543 static void reset_rbufs(struct slgt_info *info)
4544 {
4545         free_rbufs(info, 0, info->rbuf_count - 1);
4546         info->rbuf_fill_index = 0;
4547         info->rbuf_fill_count = 0;
4548 }
4549
4550 /*
4551  * pass receive HDLC frame to upper layer
4552  *
4553  * return true if frame available, otherwise false
4554  */
4555 static bool rx_get_frame(struct slgt_info *info)
4556 {
4557         unsigned int start, end;
4558         unsigned short status;
4559         unsigned int framesize = 0;
4560         unsigned long flags;
4561         struct tty_struct *tty = info->port.tty;
4562         unsigned char addr_field = 0xff;
4563         unsigned int crc_size = 0;
4564
4565         switch (info->params.crc_type & HDLC_CRC_MASK) {
4566         case HDLC_CRC_16_CCITT: crc_size = 2; break;
4567         case HDLC_CRC_32_CCITT: crc_size = 4; break;
4568         }
4569
4570 check_again:
4571
4572         framesize = 0;
4573         addr_field = 0xff;
4574         start = end = info->rbuf_current;
4575
4576         for (;;) {
4577                 if (!desc_complete(info->rbufs[end]))
4578                         goto cleanup;
4579
4580                 if (framesize == 0 && info->params.addr_filter != 0xff)
4581                         addr_field = info->rbufs[end].buf[0];
4582
4583                 framesize += desc_count(info->rbufs[end]);
4584
4585                 if (desc_eof(info->rbufs[end]))
4586                         break;
4587
4588                 if (++end == info->rbuf_count)
4589                         end = 0;
4590
4591                 if (end == info->rbuf_current) {
4592                         if (info->rx_enabled){
4593                                 spin_lock_irqsave(&info->lock,flags);
4594                                 rx_start(info);
4595                                 spin_unlock_irqrestore(&info->lock,flags);
4596                         }
4597                         goto cleanup;
4598                 }
4599         }
4600
4601         /* status
4602          *
4603          * 15      buffer complete
4604          * 14..06  reserved
4605          * 05..04  residue
4606          * 02      eof (end of frame)
4607          * 01      CRC error
4608          * 00      abort
4609          */
4610         status = desc_status(info->rbufs[end]);
4611
4612         /* ignore CRC bit if not using CRC (bit is undefined) */
4613         if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4614                 status &= ~BIT1;
4615
4616         if (framesize == 0 ||
4617                  (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4618                 free_rbufs(info, start, end);
4619                 goto check_again;
4620         }
4621
4622         if (framesize < (2 + crc_size) || status & BIT0) {
4623                 info->icount.rxshort++;
4624                 framesize = 0;
4625         } else if (status & BIT1) {
4626                 info->icount.rxcrc++;
4627                 if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4628                         framesize = 0;
4629         }
4630
4631 #if SYNCLINK_GENERIC_HDLC
4632         if (framesize == 0) {
4633                 info->netdev->stats.rx_errors++;
4634                 info->netdev->stats.rx_frame_errors++;
4635         }
4636 #endif
4637
4638         DBGBH(("%s rx frame status=%04X size=%d\n",
4639                 info->device_name, status, framesize));
4640         DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4641
4642         if (framesize) {
4643                 if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4644                         framesize -= crc_size;
4645                         crc_size = 0;
4646                 }
4647
4648                 if (framesize > info->max_frame_size + crc_size)
4649                         info->icount.rxlong++;
4650                 else {
4651                         /* copy dma buffer(s) to contiguous temp buffer */
4652                         int copy_count = framesize;
4653                         int i = start;
4654                         unsigned char *p = info->tmp_rbuf;
4655                         info->tmp_rbuf_count = framesize;
4656
4657                         info->icount.rxok++;
4658
4659                         while(copy_count) {
4660                                 int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4661                                 memcpy(p, info->rbufs[i].buf, partial_count);
4662                                 p += partial_count;
4663                                 copy_count -= partial_count;
4664                                 if (++i == info->rbuf_count)
4665                                         i = 0;
4666                         }
4667
4668                         if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4669                                 *p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4670                                 framesize++;
4671                         }
4672
4673 #if SYNCLINK_GENERIC_HDLC
4674                         if (info->netcount)
4675                                 hdlcdev_rx(info,info->tmp_rbuf, framesize);
4676                         else
4677 #endif
4678                                 ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4679                 }
4680         }
4681         free_rbufs(info, start, end);
4682         return true;
4683
4684 cleanup:
4685         return false;
4686 }
4687
4688 /*
4689  * pass receive buffer (RAW synchronous mode) to tty layer
4690  * return true if buffer available, otherwise false
4691  */
4692 static bool rx_get_buf(struct slgt_info *info)
4693 {
4694         unsigned int i = info->rbuf_current;
4695         unsigned int count;
4696
4697         if (!desc_complete(info->rbufs[i]))
4698                 return false;
4699         count = desc_count(info->rbufs[i]);
4700         switch(info->params.mode) {
4701         case MGSL_MODE_MONOSYNC:
4702         case MGSL_MODE_BISYNC:
4703         case MGSL_MODE_XSYNC:
4704                 /* ignore residue in byte synchronous modes */
4705                 if (desc_residue(info->rbufs[i]))
4706                         count--;
4707                 break;
4708         }
4709         DBGDATA(info, info->rbufs[i].buf, count, "rx");
4710         DBGINFO(("rx_get_buf size=%d\n", count));
4711         if (count)
4712                 ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4713                                   info->flag_buf, count);
4714         free_rbufs(info, i, i);
4715         return true;
4716 }
4717
4718 static void reset_tbufs(struct slgt_info *info)
4719 {
4720         unsigned int i;
4721         info->tbuf_current = 0;
4722         for (i=0 ; i < info->tbuf_count ; i++) {
4723                 info->tbufs[i].status = 0;
4724                 info->tbufs[i].count  = 0;
4725         }
4726 }
4727
4728 /*
4729  * return number of free transmit DMA buffers
4730  */
4731 static unsigned int free_tbuf_count(struct slgt_info *info)
4732 {
4733         unsigned int count = 0;
4734         unsigned int i = info->tbuf_current;
4735
4736         do
4737         {
4738                 if (desc_count(info->tbufs[i]))
4739                         break; /* buffer in use */
4740                 ++count;
4741                 if (++i == info->tbuf_count)
4742                         i=0;
4743         } while (i != info->tbuf_current);
4744
4745         /* if tx DMA active, last zero count buffer is in use */
4746         if (count && (rd_reg32(info, TDCSR) & BIT0))
4747                 --count;
4748
4749         return count;
4750 }
4751
4752 /*
4753  * return number of bytes in unsent transmit DMA buffers
4754  * and the serial controller tx FIFO
4755  */
4756 static unsigned int tbuf_bytes(struct slgt_info *info)
4757 {
4758         unsigned int total_count = 0;
4759         unsigned int i = info->tbuf_current;
4760         unsigned int reg_value;
4761         unsigned int count;
4762         unsigned int active_buf_count = 0;
4763
4764         /*
4765          * Add descriptor counts for all tx DMA buffers.
4766          * If count is zero (cleared by DMA controller after read),
4767          * the buffer is complete or is actively being read from.
4768          *
4769          * Record buf_count of last buffer with zero count starting
4770          * from current ring position. buf_count is mirror
4771          * copy of count and is not cleared by serial controller.
4772          * If DMA controller is active, that buffer is actively
4773          * being read so add to total.
4774          */
4775         do {
4776                 count = desc_count(info->tbufs[i]);
4777                 if (count)
4778                         total_count += count;
4779                 else if (!total_count)
4780                         active_buf_count = info->tbufs[i].buf_count;
4781                 if (++i == info->tbuf_count)
4782                         i = 0;
4783         } while (i != info->tbuf_current);
4784
4785         /* read tx DMA status register */
4786         reg_value = rd_reg32(info, TDCSR);
4787
4788         /* if tx DMA active, last zero count buffer is in use */
4789         if (reg_value & BIT0)
4790                 total_count += active_buf_count;
4791
4792         /* add tx FIFO count = reg_value[15..8] */
4793         total_count += (reg_value >> 8) & 0xff;
4794
4795         /* if transmitter active add one byte for shift register */
4796         if (info->tx_active)
4797                 total_count++;
4798
4799         return total_count;
4800 }
4801
4802 /*
4803  * load data into transmit DMA buffer ring and start transmitter if needed
4804  * return true if data accepted, otherwise false (buffers full)
4805  */
4806 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4807 {
4808         unsigned short count;
4809         unsigned int i;
4810         struct slgt_desc *d;
4811
4812         /* check required buffer space */
4813         if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4814                 return false;
4815
4816         DBGDATA(info, buf, size, "tx");
4817
4818         /*
4819          * copy data to one or more DMA buffers in circular ring
4820          * tbuf_start   = first buffer for this data
4821          * tbuf_current = next free buffer
4822          *
4823          * Copy all data before making data visible to DMA controller by
4824          * setting descriptor count of the first buffer.
4825          * This prevents an active DMA controller from reading the first DMA
4826          * buffers of a frame and stopping before the final buffers are filled.
4827          */
4828
4829         info->tbuf_start = i = info->tbuf_current;
4830
4831         while (size) {
4832                 d = &info->tbufs[i];
4833
4834                 count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4835                 memcpy(d->buf, buf, count);
4836
4837                 size -= count;
4838                 buf  += count;
4839
4840                 /*
4841                  * set EOF bit for last buffer of HDLC frame or
4842                  * for every buffer in raw mode
4843                  */
4844                 if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4845                     info->params.mode == MGSL_MODE_RAW)
4846                         set_desc_eof(*d, 1);
4847                 else
4848                         set_desc_eof(*d, 0);
4849
4850                 /* set descriptor count for all but first buffer */
4851                 if (i != info->tbuf_start)
4852                         set_desc_count(*d, count);
4853                 d->buf_count = count;
4854
4855                 if (++i == info->tbuf_count)
4856                         i = 0;
4857         }
4858
4859         info->tbuf_current = i;
4860
4861         /* set first buffer count to make new data visible to DMA controller */
4862         d = &info->tbufs[info->tbuf_start];
4863         set_desc_count(*d, d->buf_count);
4864
4865         /* start transmitter if needed and update transmit timeout */
4866         if (!info->tx_active)
4867                 tx_start(info);
4868         update_tx_timer(info);
4869
4870         return true;
4871 }
4872
4873 static int register_test(struct slgt_info *info)
4874 {
4875         static unsigned short patterns[] =
4876                 {0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4877         static unsigned int count = ARRAY_SIZE(patterns);
4878         unsigned int i;
4879         int rc = 0;
4880
4881         for (i=0 ; i < count ; i++) {
4882                 wr_reg16(info, TIR, patterns[i]);
4883                 wr_reg16(info, BDR, patterns[(i+1)%count]);
4884                 if ((rd_reg16(info, TIR) != patterns[i]) ||
4885                     (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4886                         rc = -ENODEV;
4887                         break;
4888                 }
4889         }
4890         info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4891         info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4892         return rc;
4893 }
4894
4895 static int irq_test(struct slgt_info *info)
4896 {
4897         unsigned long timeout;
4898         unsigned long flags;
4899         struct tty_struct *oldtty = info->port.tty;
4900         u32 speed = info->params.data_rate;
4901
4902         info->params.data_rate = 921600;
4903         info->port.tty = NULL;
4904
4905         spin_lock_irqsave(&info->lock, flags);
4906         async_mode(info);
4907         slgt_irq_on(info, IRQ_TXIDLE);
4908
4909         /* enable transmitter */
4910         wr_reg16(info, TCR,
4911                 (unsigned short)(rd_reg16(info, TCR) | BIT1));
4912
4913         /* write one byte and wait for tx idle */
4914         wr_reg16(info, TDR, 0);
4915
4916         /* assume failure */
4917         info->init_error = DiagStatus_IrqFailure;
4918         info->irq_occurred = false;
4919
4920         spin_unlock_irqrestore(&info->lock, flags);
4921
4922         timeout=100;
4923         while(timeout-- && !info->irq_occurred)
4924                 msleep_interruptible(10);
4925
4926         spin_lock_irqsave(&info->lock,flags);
4927         reset_port(info);
4928         spin_unlock_irqrestore(&info->lock,flags);
4929
4930         info->params.data_rate = speed;
4931         info->port.tty = oldtty;
4932
4933         info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
4934         return info->irq_occurred ? 0 : -ENODEV;
4935 }
4936
4937 static int loopback_test_rx(struct slgt_info *info)
4938 {
4939         unsigned char *src, *dest;
4940         int count;
4941
4942         if (desc_complete(info->rbufs[0])) {
4943                 count = desc_count(info->rbufs[0]);
4944                 src   = info->rbufs[0].buf;
4945                 dest  = info->tmp_rbuf;
4946
4947                 for( ; count ; count-=2, src+=2) {
4948                         /* src=data byte (src+1)=status byte */
4949                         if (!(*(src+1) & (BIT9 + BIT8))) {
4950                                 *dest = *src;
4951                                 dest++;
4952                                 info->tmp_rbuf_count++;
4953                         }
4954                 }
4955                 DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
4956                 return 1;
4957         }
4958         return 0;
4959 }
4960
4961 static int loopback_test(struct slgt_info *info)
4962 {
4963 #define TESTFRAMESIZE 20
4964
4965         unsigned long timeout;
4966         u16 count = TESTFRAMESIZE;
4967         unsigned char buf[TESTFRAMESIZE];
4968         int rc = -ENODEV;
4969         unsigned long flags;
4970
4971         struct tty_struct *oldtty = info->port.tty;
4972         MGSL_PARAMS params;
4973
4974         memcpy(&params, &info->params, sizeof(params));
4975
4976         info->params.mode = MGSL_MODE_ASYNC;
4977         info->params.data_rate = 921600;
4978         info->params.loopback = 1;
4979         info->port.tty = NULL;
4980
4981         /* build and send transmit frame */
4982         for (count = 0; count < TESTFRAMESIZE; ++count)
4983                 buf[count] = (unsigned char)count;
4984
4985         info->tmp_rbuf_count = 0;
4986         memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
4987
4988         /* program hardware for HDLC and enabled receiver */
4989         spin_lock_irqsave(&info->lock,flags);
4990         async_mode(info);
4991         rx_start(info);
4992         tx_load(info, buf, count);
4993         spin_unlock_irqrestore(&info->lock, flags);
4994
4995         /* wait for receive complete */
4996         for (timeout = 100; timeout; --timeout) {
4997                 msleep_interruptible(10);
4998                 if (loopback_test_rx(info)) {
4999                         rc = 0;
5000                         break;
5001                 }
5002         }
5003
5004         /* verify received frame length and contents */
5005         if (!rc && (info->tmp_rbuf_count != count ||
5006                   memcmp(buf, info->tmp_rbuf, count))) {
5007                 rc = -ENODEV;
5008         }
5009
5010         spin_lock_irqsave(&info->lock,flags);
5011         reset_adapter(info);
5012         spin_unlock_irqrestore(&info->lock,flags);
5013
5014         memcpy(&info->params, &params, sizeof(info->params));
5015         info->port.tty = oldtty;
5016
5017         info->init_error = rc ? DiagStatus_DmaFailure : 0;
5018         return rc;
5019 }
5020
5021 static int adapter_test(struct slgt_info *info)
5022 {
5023         DBGINFO(("testing %s\n", info->device_name));
5024         if (register_test(info) < 0) {
5025                 printk("register test failure %s addr=%08X\n",
5026                         info->device_name, info->phys_reg_addr);
5027         } else if (irq_test(info) < 0) {
5028                 printk("IRQ test failure %s IRQ=%d\n",
5029                         info->device_name, info->irq_level);
5030         } else if (loopback_test(info) < 0) {
5031                 printk("loopback test failure %s\n", info->device_name);
5032         }
5033         return info->init_error;
5034 }
5035
5036 /*
5037  * transmit timeout handler
5038  */
5039 static void tx_timeout(struct timer_list *t)
5040 {
5041         struct slgt_info *info = from_timer(info, t, tx_timer);
5042         unsigned long flags;
5043
5044         DBGINFO(("%s tx_timeout\n", info->device_name));
5045         if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5046                 info->icount.txtimeout++;
5047         }
5048         spin_lock_irqsave(&info->lock,flags);
5049         tx_stop(info);
5050         spin_unlock_irqrestore(&info->lock,flags);
5051
5052 #if SYNCLINK_GENERIC_HDLC
5053         if (info->netcount)
5054                 hdlcdev_tx_done(info);
5055         else
5056 #endif
5057                 bh_transmit(info);
5058 }
5059
5060 /*
5061  * receive buffer polling timer
5062  */
5063 static void rx_timeout(struct timer_list *t)
5064 {
5065         struct slgt_info *info = from_timer(info, t, rx_timer);
5066         unsigned long flags;
5067
5068         DBGINFO(("%s rx_timeout\n", info->device_name));
5069         spin_lock_irqsave(&info->lock, flags);
5070         info->pending_bh |= BH_RECEIVE;
5071         spin_unlock_irqrestore(&info->lock, flags);
5072         bh_handler(&info->task);
5073 }
5074