GNU Linux-libre 4.19.286-gnu1
[releases.git] / drivers / usb / serial / belkin_sa.c
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Belkin USB Serial Adapter Driver
4  *
5  *  Copyright (C) 2000          William Greathouse (wgreathouse@smva.com)
6  *  Copyright (C) 2000-2001     Greg Kroah-Hartman (greg@kroah.com)
7  *  Copyright (C) 2010          Johan Hovold (jhovold@gmail.com)
8  *
9  *  This program is largely derived from work by the linux-usb group
10  *  and associated source files.  Please see the usb/serial files for
11  *  individual credits and copyrights.
12  *
13  * See Documentation/usb/usb-serial.txt for more information on using this
14  * driver
15  *
16  * TODO:
17  * -- Add true modem control line query capability.  Currently we track the
18  *    states reported by the interrupt and the states we request.
19  * -- Add support for flush commands
20  */
21
22 #include <linux/kernel.h>
23 #include <linux/errno.h>
24 #include <linux/slab.h>
25 #include <linux/tty.h>
26 #include <linux/tty_driver.h>
27 #include <linux/tty_flip.h>
28 #include <linux/module.h>
29 #include <linux/spinlock.h>
30 #include <linux/uaccess.h>
31 #include <linux/usb.h>
32 #include <linux/usb/serial.h>
33 #include "belkin_sa.h"
34
35 #define DRIVER_AUTHOR "William Greathouse <wgreathouse@smva.com>"
36 #define DRIVER_DESC "USB Belkin Serial converter driver"
37
38 /* function prototypes for a Belkin USB Serial Adapter F5U103 */
39 static int belkin_sa_port_probe(struct usb_serial_port *port);
40 static int belkin_sa_port_remove(struct usb_serial_port *port);
41 static int  belkin_sa_open(struct tty_struct *tty,
42                         struct usb_serial_port *port);
43 static void belkin_sa_close(struct usb_serial_port *port);
44 static void belkin_sa_read_int_callback(struct urb *urb);
45 static void belkin_sa_process_read_urb(struct urb *urb);
46 static void belkin_sa_set_termios(struct tty_struct *tty,
47                         struct usb_serial_port *port, struct ktermios * old);
48 static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state);
49 static int  belkin_sa_tiocmget(struct tty_struct *tty);
50 static int  belkin_sa_tiocmset(struct tty_struct *tty,
51                                         unsigned int set, unsigned int clear);
52
53
54 static const struct usb_device_id id_table[] = {
55         { USB_DEVICE(BELKIN_SA_VID, BELKIN_SA_PID) },
56         { USB_DEVICE(BELKIN_OLD_VID, BELKIN_OLD_PID) },
57         { USB_DEVICE(PERACOM_VID, PERACOM_PID) },
58         { USB_DEVICE(GOHUBS_VID, GOHUBS_PID) },
59         { USB_DEVICE(GOHUBS_VID, HANDYLINK_PID) },
60         { USB_DEVICE(BELKIN_DOCKSTATION_VID, BELKIN_DOCKSTATION_PID) },
61         { }     /* Terminating entry */
62 };
63 MODULE_DEVICE_TABLE(usb, id_table);
64
65 /* All of the device info needed for the serial converters */
66 static struct usb_serial_driver belkin_device = {
67         .driver = {
68                 .owner =        THIS_MODULE,
69                 .name =         "belkin",
70         },
71         .description =          "Belkin / Peracom / GoHubs USB Serial Adapter",
72         .id_table =             id_table,
73         .num_ports =            1,
74         .open =                 belkin_sa_open,
75         .close =                belkin_sa_close,
76         .read_int_callback =    belkin_sa_read_int_callback,
77         .process_read_urb =     belkin_sa_process_read_urb,
78         .set_termios =          belkin_sa_set_termios,
79         .break_ctl =            belkin_sa_break_ctl,
80         .tiocmget =             belkin_sa_tiocmget,
81         .tiocmset =             belkin_sa_tiocmset,
82         .port_probe =           belkin_sa_port_probe,
83         .port_remove =          belkin_sa_port_remove,
84 };
85
86 static struct usb_serial_driver * const serial_drivers[] = {
87         &belkin_device, NULL
88 };
89
90 struct belkin_sa_private {
91         spinlock_t              lock;
92         unsigned long           control_state;
93         unsigned char           last_lsr;
94         unsigned char           last_msr;
95         int                     bad_flow_control;
96 };
97
98
99 /*
100  * ***************************************************************************
101  * Belkin USB Serial Adapter F5U103 specific driver functions
102  * ***************************************************************************
103  */
104
105 #define WDR_TIMEOUT 5000 /* default urb timeout */
106
107 /* assumes that struct usb_serial *serial is available */
108 #define BSA_USB_CMD(c, v) usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), \
109                                             (c), BELKIN_SA_SET_REQUEST_TYPE, \
110                                             (v), 0, NULL, 0, WDR_TIMEOUT)
111
112 static int belkin_sa_port_probe(struct usb_serial_port *port)
113 {
114         struct usb_device *dev = port->serial->dev;
115         struct belkin_sa_private *priv;
116
117         priv = kmalloc(sizeof(struct belkin_sa_private), GFP_KERNEL);
118         if (!priv)
119                 return -ENOMEM;
120
121         spin_lock_init(&priv->lock);
122         priv->control_state = 0;
123         priv->last_lsr = 0;
124         priv->last_msr = 0;
125         /* see comments at top of file */
126         priv->bad_flow_control =
127                 (le16_to_cpu(dev->descriptor.bcdDevice) <= 0x0206) ? 1 : 0;
128         dev_info(&dev->dev, "bcdDevice: %04x, bfc: %d\n",
129                                         le16_to_cpu(dev->descriptor.bcdDevice),
130                                         priv->bad_flow_control);
131
132         usb_set_serial_port_data(port, priv);
133
134         return 0;
135 }
136
137 static int belkin_sa_port_remove(struct usb_serial_port *port)
138 {
139         struct belkin_sa_private *priv;
140
141         priv = usb_get_serial_port_data(port);
142         kfree(priv);
143
144         return 0;
145 }
146
147 static int belkin_sa_open(struct tty_struct *tty,
148                                         struct usb_serial_port *port)
149 {
150         int retval;
151
152         retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
153         if (retval) {
154                 dev_err(&port->dev, "usb_submit_urb(read int) failed\n");
155                 return retval;
156         }
157
158         retval = usb_serial_generic_open(tty, port);
159         if (retval)
160                 usb_kill_urb(port->interrupt_in_urb);
161
162         return retval;
163 }
164
165 static void belkin_sa_close(struct usb_serial_port *port)
166 {
167         usb_serial_generic_close(port);
168         usb_kill_urb(port->interrupt_in_urb);
169 }
170
171 static void belkin_sa_read_int_callback(struct urb *urb)
172 {
173         struct usb_serial_port *port = urb->context;
174         struct belkin_sa_private *priv;
175         unsigned char *data = urb->transfer_buffer;
176         int retval;
177         int status = urb->status;
178         unsigned long flags;
179
180         switch (status) {
181         case 0:
182                 /* success */
183                 break;
184         case -ECONNRESET:
185         case -ENOENT:
186         case -ESHUTDOWN:
187                 /* this urb is terminated, clean up */
188                 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
189                         __func__, status);
190                 return;
191         default:
192                 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
193                         __func__, status);
194                 goto exit;
195         }
196
197         usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
198
199         /* Handle known interrupt data */
200         /* ignore data[0] and data[1] */
201
202         priv = usb_get_serial_port_data(port);
203         spin_lock_irqsave(&priv->lock, flags);
204         priv->last_msr = data[BELKIN_SA_MSR_INDEX];
205
206         /* Record Control Line states */
207         if (priv->last_msr & BELKIN_SA_MSR_DSR)
208                 priv->control_state |= TIOCM_DSR;
209         else
210                 priv->control_state &= ~TIOCM_DSR;
211
212         if (priv->last_msr & BELKIN_SA_MSR_CTS)
213                 priv->control_state |= TIOCM_CTS;
214         else
215                 priv->control_state &= ~TIOCM_CTS;
216
217         if (priv->last_msr & BELKIN_SA_MSR_RI)
218                 priv->control_state |= TIOCM_RI;
219         else
220                 priv->control_state &= ~TIOCM_RI;
221
222         if (priv->last_msr & BELKIN_SA_MSR_CD)
223                 priv->control_state |= TIOCM_CD;
224         else
225                 priv->control_state &= ~TIOCM_CD;
226
227         priv->last_lsr = data[BELKIN_SA_LSR_INDEX];
228         spin_unlock_irqrestore(&priv->lock, flags);
229 exit:
230         retval = usb_submit_urb(urb, GFP_ATOMIC);
231         if (retval)
232                 dev_err(&port->dev, "%s - usb_submit_urb failed with "
233                         "result %d\n", __func__, retval);
234 }
235
236 static void belkin_sa_process_read_urb(struct urb *urb)
237 {
238         struct usb_serial_port *port = urb->context;
239         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
240         unsigned char *data = urb->transfer_buffer;
241         unsigned long flags;
242         unsigned char status;
243         char tty_flag;
244
245         /* Update line status */
246         tty_flag = TTY_NORMAL;
247
248         spin_lock_irqsave(&priv->lock, flags);
249         status = priv->last_lsr;
250         priv->last_lsr &= ~BELKIN_SA_LSR_ERR;
251         spin_unlock_irqrestore(&priv->lock, flags);
252
253         if (!urb->actual_length)
254                 return;
255
256         if (status & BELKIN_SA_LSR_ERR) {
257                 /* Break takes precedence over parity, which takes precedence
258                  * over framing errors. */
259                 if (status & BELKIN_SA_LSR_BI)
260                         tty_flag = TTY_BREAK;
261                 else if (status & BELKIN_SA_LSR_PE)
262                         tty_flag = TTY_PARITY;
263                 else if (status & BELKIN_SA_LSR_FE)
264                         tty_flag = TTY_FRAME;
265                 dev_dbg(&port->dev, "tty_flag = %d\n", tty_flag);
266
267                 /* Overrun is special, not associated with a char. */
268                 if (status & BELKIN_SA_LSR_OE)
269                         tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
270         }
271
272         tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
273                                                         urb->actual_length);
274         tty_flip_buffer_push(&port->port);
275 }
276
277 static void belkin_sa_set_termios(struct tty_struct *tty,
278                 struct usb_serial_port *port, struct ktermios *old_termios)
279 {
280         struct usb_serial *serial = port->serial;
281         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
282         unsigned int iflag;
283         unsigned int cflag;
284         unsigned int old_iflag = 0;
285         unsigned int old_cflag = 0;
286         __u16 urb_value = 0; /* Will hold the new flags */
287         unsigned long flags;
288         unsigned long control_state;
289         int bad_flow_control;
290         speed_t baud;
291         struct ktermios *termios = &tty->termios;
292
293         iflag = termios->c_iflag;
294         cflag = termios->c_cflag;
295
296         termios->c_cflag &= ~CMSPAR;
297
298         /* get a local copy of the current port settings */
299         spin_lock_irqsave(&priv->lock, flags);
300         control_state = priv->control_state;
301         bad_flow_control = priv->bad_flow_control;
302         spin_unlock_irqrestore(&priv->lock, flags);
303
304         old_iflag = old_termios->c_iflag;
305         old_cflag = old_termios->c_cflag;
306
307         /* Set the baud rate */
308         if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
309                 /* reassert DTR and (maybe) RTS on transition from B0 */
310                 if ((old_cflag & CBAUD) == B0) {
311                         control_state |= (TIOCM_DTR|TIOCM_RTS);
312                         if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0)
313                                 dev_err(&port->dev, "Set DTR error\n");
314                         /* don't set RTS if using hardware flow control */
315                         if (!(old_cflag & CRTSCTS))
316                                 if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST
317                                                                 , 1) < 0)
318                                         dev_err(&port->dev, "Set RTS error\n");
319                 }
320         }
321
322         baud = tty_get_baud_rate(tty);
323         if (baud) {
324                 urb_value = BELKIN_SA_BAUD(baud);
325                 /* Clip to maximum speed */
326                 if (urb_value == 0)
327                         urb_value = 1;
328                 /* Turn it back into a resulting real baud rate */
329                 baud = BELKIN_SA_BAUD(urb_value);
330
331                 /* Report the actual baud rate back to the caller */
332                 tty_encode_baud_rate(tty, baud, baud);
333                 if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0)
334                         dev_err(&port->dev, "Set baudrate error\n");
335         } else {
336                 /* Disable flow control */
337                 if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST,
338                                                 BELKIN_SA_FLOW_NONE) < 0)
339                         dev_err(&port->dev, "Disable flowcontrol error\n");
340                 /* Drop RTS and DTR */
341                 control_state &= ~(TIOCM_DTR | TIOCM_RTS);
342                 if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0)
343                         dev_err(&port->dev, "DTR LOW error\n");
344                 if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0)
345                         dev_err(&port->dev, "RTS LOW error\n");
346         }
347
348         /* set the parity */
349         if ((cflag ^ old_cflag) & (PARENB | PARODD)) {
350                 if (cflag & PARENB)
351                         urb_value = (cflag & PARODD) ?  BELKIN_SA_PARITY_ODD
352                                                 : BELKIN_SA_PARITY_EVEN;
353                 else
354                         urb_value = BELKIN_SA_PARITY_NONE;
355                 if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0)
356                         dev_err(&port->dev, "Set parity error\n");
357         }
358
359         /* set the number of data bits */
360         if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
361                 switch (cflag & CSIZE) {
362                 case CS5:
363                         urb_value = BELKIN_SA_DATA_BITS(5);
364                         break;
365                 case CS6:
366                         urb_value = BELKIN_SA_DATA_BITS(6);
367                         break;
368                 case CS7:
369                         urb_value = BELKIN_SA_DATA_BITS(7);
370                         break;
371                 case CS8:
372                         urb_value = BELKIN_SA_DATA_BITS(8);
373                         break;
374                 default:
375                         dev_dbg(&port->dev,
376                                 "CSIZE was not CS5-CS8, using default of 8\n");
377                         urb_value = BELKIN_SA_DATA_BITS(8);
378                         break;
379                 }
380                 if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0)
381                         dev_err(&port->dev, "Set data bits error\n");
382         }
383
384         /* set the number of stop bits */
385         if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
386                 urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2)
387                                                 : BELKIN_SA_STOP_BITS(1);
388                 if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST,
389                                                         urb_value) < 0)
390                         dev_err(&port->dev, "Set stop bits error\n");
391         }
392
393         /* Set flow control */
394         if (((iflag ^ old_iflag) & (IXOFF | IXON)) ||
395                 ((cflag ^ old_cflag) & CRTSCTS)) {
396                 urb_value = 0;
397                 if ((iflag & IXOFF) || (iflag & IXON))
398                         urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
399                 else
400                         urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
401
402                 if (cflag & CRTSCTS)
403                         urb_value |=  (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
404                 else
405                         urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
406
407                 if (bad_flow_control)
408                         urb_value &= ~(BELKIN_SA_FLOW_IRTS);
409
410                 if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0)
411                         dev_err(&port->dev, "Set flow control error\n");
412         }
413
414         /* save off the modified port settings */
415         spin_lock_irqsave(&priv->lock, flags);
416         priv->control_state = control_state;
417         spin_unlock_irqrestore(&priv->lock, flags);
418 }
419
420 static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state)
421 {
422         struct usb_serial_port *port = tty->driver_data;
423         struct usb_serial *serial = port->serial;
424
425         if (BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0) < 0)
426                 dev_err(&port->dev, "Set break_ctl %d\n", break_state);
427 }
428
429 static int belkin_sa_tiocmget(struct tty_struct *tty)
430 {
431         struct usb_serial_port *port = tty->driver_data;
432         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
433         unsigned long control_state;
434         unsigned long flags;
435
436         spin_lock_irqsave(&priv->lock, flags);
437         control_state = priv->control_state;
438         spin_unlock_irqrestore(&priv->lock, flags);
439
440         return control_state;
441 }
442
443 static int belkin_sa_tiocmset(struct tty_struct *tty,
444                                unsigned int set, unsigned int clear)
445 {
446         struct usb_serial_port *port = tty->driver_data;
447         struct usb_serial *serial = port->serial;
448         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
449         unsigned long control_state;
450         unsigned long flags;
451         int retval;
452         int rts = 0;
453         int dtr = 0;
454
455         spin_lock_irqsave(&priv->lock, flags);
456         control_state = priv->control_state;
457
458         if (set & TIOCM_RTS) {
459                 control_state |= TIOCM_RTS;
460                 rts = 1;
461         }
462         if (set & TIOCM_DTR) {
463                 control_state |= TIOCM_DTR;
464                 dtr = 1;
465         }
466         if (clear & TIOCM_RTS) {
467                 control_state &= ~TIOCM_RTS;
468                 rts = 0;
469         }
470         if (clear & TIOCM_DTR) {
471                 control_state &= ~TIOCM_DTR;
472                 dtr = 0;
473         }
474
475         priv->control_state = control_state;
476         spin_unlock_irqrestore(&priv->lock, flags);
477
478         retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts);
479         if (retval < 0) {
480                 dev_err(&port->dev, "Set RTS error %d\n", retval);
481                 goto exit;
482         }
483
484         retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr);
485         if (retval < 0) {
486                 dev_err(&port->dev, "Set DTR error %d\n", retval);
487                 goto exit;
488         }
489 exit:
490         return retval;
491 }
492
493 module_usb_serial_driver(serial_drivers, id_table);
494
495 MODULE_AUTHOR(DRIVER_AUTHOR);
496 MODULE_DESCRIPTION(DRIVER_DESC);
497 MODULE_LICENSE("GPL");