GNU Linux-libre 4.19.286-gnu1
[releases.git] / drivers / usb / serial / ir-usb.c
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * USB IR Dongle driver
4  *
5  *      Copyright (C) 2001-2002 Greg Kroah-Hartman (greg@kroah.com)
6  *      Copyright (C) 2002      Gary Brubaker (xavyer@ix.netcom.com)
7  *      Copyright (C) 2010      Johan Hovold (jhovold@gmail.com)
8  *
9  * This driver allows a USB IrDA device to be used as a "dumb" serial device.
10  * This can be useful if you do not have access to a full IrDA stack on the
11  * other side of the connection.  If you do have an IrDA stack on both devices,
12  * please use the usb-irda driver, as it contains the proper error checking and
13  * other goodness of a full IrDA stack.
14  *
15  * Portions of this driver were taken from drivers/net/irda/irda-usb.c, which
16  * was written by Roman Weissgaerber <weissg@vienna.at>, Dag Brattli
17  * <dag@brattli.net>, and Jean Tourrilhes <jt@hpl.hp.com>
18  *
19  * See Documentation/usb/usb-serial.txt for more information on using this
20  * driver
21  */
22
23 #include <linux/kernel.h>
24 #include <linux/errno.h>
25 #include <linux/init.h>
26 #include <linux/slab.h>
27 #include <linux/tty.h>
28 #include <linux/tty_driver.h>
29 #include <linux/tty_flip.h>
30 #include <linux/module.h>
31 #include <linux/spinlock.h>
32 #include <linux/uaccess.h>
33 #include <linux/usb.h>
34 #include <linux/usb/serial.h>
35 #include <linux/usb/irda.h>
36
37 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Johan Hovold <jhovold@gmail.com>"
38 #define DRIVER_DESC "USB IR Dongle driver"
39
40 /* if overridden by the user, then use their value for the size of the read and
41  * write urbs */
42 static int buffer_size;
43
44 /* if overridden by the user, then use the specified number of XBOFs */
45 static int xbof = -1;
46
47 static int  ir_startup (struct usb_serial *serial);
48 static int ir_write(struct tty_struct *tty, struct usb_serial_port *port,
49                 const unsigned char *buf, int count);
50 static int ir_write_room(struct tty_struct *tty);
51 static void ir_write_bulk_callback(struct urb *urb);
52 static void ir_process_read_urb(struct urb *urb);
53 static void ir_set_termios(struct tty_struct *tty,
54                 struct usb_serial_port *port, struct ktermios *old_termios);
55
56 /* Not that this lot means you can only have one per system */
57 static u8 ir_baud;
58 static u8 ir_xbof;
59 static u8 ir_add_bof;
60
61 static const struct usb_device_id ir_id_table[] = {
62         { USB_DEVICE(0x050f, 0x0180) },         /* KC Technology, KC-180 */
63         { USB_DEVICE(0x08e9, 0x0100) },         /* XTNDAccess */
64         { USB_DEVICE(0x09c4, 0x0011) },         /* ACTiSys ACT-IR2000U */
65         { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, USB_SUBCLASS_IRDA, 0) },
66         { }                                     /* Terminating entry */
67 };
68
69 MODULE_DEVICE_TABLE(usb, ir_id_table);
70
71 static struct usb_serial_driver ir_device = {
72         .driver = {
73                 .owner  = THIS_MODULE,
74                 .name   = "ir-usb",
75         },
76         .description            = "IR Dongle",
77         .id_table               = ir_id_table,
78         .num_ports              = 1,
79         .set_termios            = ir_set_termios,
80         .attach                 = ir_startup,
81         .write                  = ir_write,
82         .write_room             = ir_write_room,
83         .write_bulk_callback    = ir_write_bulk_callback,
84         .process_read_urb       = ir_process_read_urb,
85 };
86
87 static struct usb_serial_driver * const serial_drivers[] = {
88         &ir_device, NULL
89 };
90
91 static inline void irda_usb_dump_class_desc(struct usb_serial *serial,
92                                             struct usb_irda_cs_descriptor *desc)
93 {
94         struct device *dev = &serial->dev->dev;
95
96         dev_dbg(dev, "bLength=%x\n", desc->bLength);
97         dev_dbg(dev, "bDescriptorType=%x\n", desc->bDescriptorType);
98         dev_dbg(dev, "bcdSpecRevision=%x\n", __le16_to_cpu(desc->bcdSpecRevision));
99         dev_dbg(dev, "bmDataSize=%x\n", desc->bmDataSize);
100         dev_dbg(dev, "bmWindowSize=%x\n", desc->bmWindowSize);
101         dev_dbg(dev, "bmMinTurnaroundTime=%d\n", desc->bmMinTurnaroundTime);
102         dev_dbg(dev, "wBaudRate=%x\n", __le16_to_cpu(desc->wBaudRate));
103         dev_dbg(dev, "bmAdditionalBOFs=%x\n", desc->bmAdditionalBOFs);
104         dev_dbg(dev, "bIrdaRateSniff=%x\n", desc->bIrdaRateSniff);
105         dev_dbg(dev, "bMaxUnicastList=%x\n", desc->bMaxUnicastList);
106 }
107
108 /*------------------------------------------------------------------*/
109 /*
110  * Function irda_usb_find_class_desc(dev, ifnum)
111  *
112  *    Returns instance of IrDA class descriptor, or NULL if not found
113  *
114  * The class descriptor is some extra info that IrDA USB devices will
115  * offer to us, describing their IrDA characteristics. We will use that in
116  * irda_usb_init_qos()
117  *
118  * Based on the same function in drivers/net/irda/irda-usb.c
119  */
120 static struct usb_irda_cs_descriptor *
121 irda_usb_find_class_desc(struct usb_serial *serial, unsigned int ifnum)
122 {
123         struct usb_device *dev = serial->dev;
124         struct usb_irda_cs_descriptor *desc;
125         int ret;
126
127         desc = kzalloc(sizeof(*desc), GFP_KERNEL);
128         if (!desc)
129                 return NULL;
130
131         ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
132                         USB_REQ_CS_IRDA_GET_CLASS_DESC,
133                         USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
134                         0, ifnum, desc, sizeof(*desc), 1000);
135
136         dev_dbg(&serial->dev->dev, "%s -  ret=%d\n", __func__, ret);
137         if (ret < (int)sizeof(*desc)) {
138                 dev_dbg(&serial->dev->dev,
139                         "%s - class descriptor read %s (%d)\n", __func__,
140                         (ret < 0) ? "failed" : "too short", ret);
141                 goto error;
142         }
143         if (desc->bDescriptorType != USB_DT_CS_IRDA) {
144                 dev_dbg(&serial->dev->dev, "%s - bad class descriptor type\n",
145                         __func__);
146                 goto error;
147         }
148
149         irda_usb_dump_class_desc(serial, desc);
150         return desc;
151
152 error:
153         kfree(desc);
154         return NULL;
155 }
156
157 static u8 ir_xbof_change(u8 xbof)
158 {
159         u8 result;
160
161         /* reference irda-usb.c */
162         switch (xbof) {
163         case 48:
164                 result = 0x10;
165                 break;
166         case 28:
167         case 24:
168                 result = 0x20;
169                 break;
170         default:
171         case 12:
172                 result = 0x30;
173                 break;
174         case  5:
175         case  6:
176                 result = 0x40;
177                 break;
178         case  3:
179                 result = 0x50;
180                 break;
181         case  2:
182                 result = 0x60;
183                 break;
184         case  1:
185                 result = 0x70;
186                 break;
187         case  0:
188                 result = 0x80;
189                 break;
190         }
191
192         return(result);
193 }
194
195 static int ir_startup(struct usb_serial *serial)
196 {
197         struct usb_irda_cs_descriptor *irda_desc;
198         int rates;
199
200         if (serial->num_bulk_in < 1 || serial->num_bulk_out < 1)
201                 return -ENODEV;
202
203         irda_desc = irda_usb_find_class_desc(serial, 0);
204         if (!irda_desc) {
205                 dev_err(&serial->dev->dev,
206                         "IRDA class descriptor not found, device not bound\n");
207                 return -ENODEV;
208         }
209
210         rates = le16_to_cpu(irda_desc->wBaudRate);
211
212         dev_dbg(&serial->dev->dev,
213                 "%s - Baud rates supported:%s%s%s%s%s%s%s%s%s\n",
214                 __func__,
215                 (rates & USB_IRDA_BR_2400) ? " 2400" : "",
216                 (rates & USB_IRDA_BR_9600) ? " 9600" : "",
217                 (rates & USB_IRDA_BR_19200) ? " 19200" : "",
218                 (rates & USB_IRDA_BR_38400) ? " 38400" : "",
219                 (rates & USB_IRDA_BR_57600) ? " 57600" : "",
220                 (rates & USB_IRDA_BR_115200) ? " 115200" : "",
221                 (rates & USB_IRDA_BR_576000) ? " 576000" : "",
222                 (rates & USB_IRDA_BR_1152000) ? " 1152000" : "",
223                 (rates & USB_IRDA_BR_4000000) ? " 4000000" : "");
224
225         switch (irda_desc->bmAdditionalBOFs) {
226         case USB_IRDA_AB_48:
227                 ir_add_bof = 48;
228                 break;
229         case USB_IRDA_AB_24:
230                 ir_add_bof = 24;
231                 break;
232         case USB_IRDA_AB_12:
233                 ir_add_bof = 12;
234                 break;
235         case USB_IRDA_AB_6:
236                 ir_add_bof = 6;
237                 break;
238         case USB_IRDA_AB_3:
239                 ir_add_bof = 3;
240                 break;
241         case USB_IRDA_AB_2:
242                 ir_add_bof = 2;
243                 break;
244         case USB_IRDA_AB_1:
245                 ir_add_bof = 1;
246                 break;
247         case USB_IRDA_AB_0:
248                 ir_add_bof = 0;
249                 break;
250         default:
251                 break;
252         }
253
254         kfree(irda_desc);
255
256         return 0;
257 }
258
259 static int ir_write(struct tty_struct *tty, struct usb_serial_port *port,
260                 const unsigned char *buf, int count)
261 {
262         struct urb *urb = NULL;
263         unsigned long flags;
264         int ret;
265
266         if (port->bulk_out_size == 0)
267                 return -EINVAL;
268
269         if (count == 0)
270                 return 0;
271
272         count = min(count, port->bulk_out_size - 1);
273
274         spin_lock_irqsave(&port->lock, flags);
275         if (__test_and_clear_bit(0, &port->write_urbs_free)) {
276                 urb = port->write_urbs[0];
277                 port->tx_bytes += count;
278         }
279         spin_unlock_irqrestore(&port->lock, flags);
280
281         if (!urb)
282                 return 0;
283
284         /*
285          * The first byte of the packet we send to the device contains an
286          * outbound header which indicates an additional number of BOFs and
287          * a baud rate change.
288          *
289          * See section 5.4.2.2 of the USB IrDA spec.
290          */
291         *(u8 *)urb->transfer_buffer = ir_xbof | ir_baud;
292
293         memcpy(urb->transfer_buffer + 1, buf, count);
294
295         urb->transfer_buffer_length = count + 1;
296         urb->transfer_flags = URB_ZERO_PACKET;
297
298         ret = usb_submit_urb(urb, GFP_ATOMIC);
299         if (ret) {
300                 dev_err(&port->dev, "failed to submit write urb: %d\n", ret);
301
302                 spin_lock_irqsave(&port->lock, flags);
303                 __set_bit(0, &port->write_urbs_free);
304                 port->tx_bytes -= count;
305                 spin_unlock_irqrestore(&port->lock, flags);
306
307                 return ret;
308         }
309
310         return count;
311 }
312
313 static void ir_write_bulk_callback(struct urb *urb)
314 {
315         struct usb_serial_port *port = urb->context;
316         int status = urb->status;
317         unsigned long flags;
318
319         spin_lock_irqsave(&port->lock, flags);
320         __set_bit(0, &port->write_urbs_free);
321         port->tx_bytes -= urb->transfer_buffer_length - 1;
322         spin_unlock_irqrestore(&port->lock, flags);
323
324         switch (status) {
325         case 0:
326                 break;
327         case -ENOENT:
328         case -ECONNRESET:
329         case -ESHUTDOWN:
330                 dev_dbg(&port->dev, "write urb stopped: %d\n", status);
331                 return;
332         case -EPIPE:
333                 dev_err(&port->dev, "write urb stopped: %d\n", status);
334                 return;
335         default:
336                 dev_err(&port->dev, "nonzero write-urb status: %d\n", status);
337                 break;
338         }
339
340         usb_serial_port_softint(port);
341 }
342
343 static int ir_write_room(struct tty_struct *tty)
344 {
345         struct usb_serial_port *port = tty->driver_data;
346         int count = 0;
347
348         if (port->bulk_out_size == 0)
349                 return 0;
350
351         if (test_bit(0, &port->write_urbs_free))
352                 count = port->bulk_out_size - 1;
353
354         return count;
355 }
356
357 static void ir_process_read_urb(struct urb *urb)
358 {
359         struct usb_serial_port *port = urb->context;
360         unsigned char *data = urb->transfer_buffer;
361
362         if (!urb->actual_length)
363                 return;
364         /*
365          * The first byte of the packet we get from the device
366          * contains a busy indicator and baud rate change.
367          * See section 5.4.1.2 of the USB IrDA spec.
368          */
369         if (*data & 0x0f)
370                 ir_baud = *data & 0x0f;
371
372         if (urb->actual_length == 1)
373                 return;
374
375         tty_insert_flip_string(&port->port, data + 1, urb->actual_length - 1);
376         tty_flip_buffer_push(&port->port);
377 }
378
379 static void ir_set_termios_callback(struct urb *urb)
380 {
381         kfree(urb->transfer_buffer);
382
383         if (urb->status)
384                 dev_dbg(&urb->dev->dev, "%s - non-zero urb status: %d\n",
385                         __func__, urb->status);
386 }
387
388 static void ir_set_termios(struct tty_struct *tty,
389                 struct usb_serial_port *port, struct ktermios *old_termios)
390 {
391         struct urb *urb;
392         unsigned char *transfer_buffer;
393         int result;
394         speed_t baud;
395         int ir_baud;
396
397         baud = tty_get_baud_rate(tty);
398
399         /*
400          * FIXME, we should compare the baud request against the
401          * capability stated in the IR header that we got in the
402          * startup function.
403          */
404
405         switch (baud) {
406         case 2400:
407                 ir_baud = USB_IRDA_LS_2400;
408                 break;
409         case 9600:
410                 ir_baud = USB_IRDA_LS_9600;
411                 break;
412         case 19200:
413                 ir_baud = USB_IRDA_LS_19200;
414                 break;
415         case 38400:
416                 ir_baud = USB_IRDA_LS_38400;
417                 break;
418         case 57600:
419                 ir_baud = USB_IRDA_LS_57600;
420                 break;
421         case 115200:
422                 ir_baud = USB_IRDA_LS_115200;
423                 break;
424         case 576000:
425                 ir_baud = USB_IRDA_LS_576000;
426                 break;
427         case 1152000:
428                 ir_baud = USB_IRDA_LS_1152000;
429                 break;
430         case 4000000:
431                 ir_baud = USB_IRDA_LS_4000000;
432                 break;
433         default:
434                 ir_baud = USB_IRDA_LS_9600;
435                 baud = 9600;
436         }
437
438         if (xbof == -1)
439                 ir_xbof = ir_xbof_change(ir_add_bof);
440         else
441                 ir_xbof = ir_xbof_change(xbof) ;
442
443         /* Only speed changes are supported */
444         tty_termios_copy_hw(&tty->termios, old_termios);
445         tty_encode_baud_rate(tty, baud, baud);
446
447         /*
448          * send the baud change out on an "empty" data packet
449          */
450         urb = usb_alloc_urb(0, GFP_KERNEL);
451         if (!urb)
452                 return;
453
454         transfer_buffer = kmalloc(1, GFP_KERNEL);
455         if (!transfer_buffer)
456                 goto err_buf;
457
458         *transfer_buffer = ir_xbof | ir_baud;
459
460         usb_fill_bulk_urb(
461                 urb,
462                 port->serial->dev,
463                 usb_sndbulkpipe(port->serial->dev,
464                         port->bulk_out_endpointAddress),
465                 transfer_buffer,
466                 1,
467                 ir_set_termios_callback,
468                 port);
469
470         urb->transfer_flags = URB_ZERO_PACKET;
471
472         result = usb_submit_urb(urb, GFP_KERNEL);
473         if (result) {
474                 dev_err(&port->dev, "%s - failed to submit urb: %d\n",
475                                                         __func__, result);
476                 goto err_subm;
477         }
478
479         usb_free_urb(urb);
480
481         return;
482 err_subm:
483         kfree(transfer_buffer);
484 err_buf:
485         usb_free_urb(urb);
486 }
487
488 static int __init ir_init(void)
489 {
490         if (buffer_size) {
491                 ir_device.bulk_in_size = buffer_size;
492                 ir_device.bulk_out_size = buffer_size;
493         }
494
495         return usb_serial_register_drivers(serial_drivers, KBUILD_MODNAME, ir_id_table);
496 }
497
498 static void __exit ir_exit(void)
499 {
500         usb_serial_deregister_drivers(serial_drivers);
501 }
502
503
504 module_init(ir_init);
505 module_exit(ir_exit);
506
507 MODULE_AUTHOR(DRIVER_AUTHOR);
508 MODULE_DESCRIPTION(DRIVER_DESC);
509 MODULE_LICENSE("GPL");
510
511 module_param(xbof, int, 0);
512 MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
513 module_param(buffer_size, int, 0);
514 MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");
515