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1/*
2 USB Driver layer for GSM modems
3
4 Copyright (C) 2005 Matthias Urlichs <smurf@smurf.noris.de>
5
6 This driver is free software; you can redistribute it and/or modify
7 it under the terms of Version 2 of the GNU General Public License as
8 published by the Free Software Foundation.
9
10 Portions copied from the Keyspan driver by Hugh Blemings <hugh@blemings.org>
11
12 History: see the git log.
13
14 Work sponsored by: Sigos GmbH, Germany <info@sigos.de>
15
16 This driver exists because the "normal" serial driver doesn't work too well
17 with GSM modems. Issues:
18 - data loss -- one single Receive URB is not nearly enough
19 - controlling the baud rate doesn't make sense
20*/
21
22#define DRIVER_AUTHOR "Matthias Urlichs <smurf@smurf.noris.de>"
23#define DRIVER_DESC "USB Driver for GSM modems"
24
25#include <linux/kernel.h>
26#include <linux/jiffies.h>
27#include <linux/errno.h>
28#include <linux/slab.h>
29#include <linux/tty.h>
30#include <linux/tty_flip.h>
31#include <linux/module.h>
32#include <linux/bitops.h>
33#include <linux/uaccess.h>
34#include <linux/usb.h>
35#include <linux/usb/serial.h>
36#include <linux/serial.h>
37#include "usb-wwan.h"
38
39/*
40 * Generate DTR/RTS signals on the port using the SET_CONTROL_LINE_STATE request
41 * in CDC ACM.
42 */
43static int usb_wwan_send_setup(struct usb_serial_port *port)
44{
45 struct usb_serial *serial = port->serial;
46 struct usb_wwan_port_private *portdata;
47 int val = 0;
48 int ifnum;
49 int res;
50
51 portdata = usb_get_serial_port_data(port);
52
53 if (portdata->dtr_state)
54 val |= 0x01;
55 if (portdata->rts_state)
56 val |= 0x02;
57
58 ifnum = serial->interface->cur_altsetting->desc.bInterfaceNumber;
59
60 res = usb_autopm_get_interface(serial->interface);
61 if (res)
62 return res;
63
64 res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
65 0x22, 0x21, val, ifnum, NULL, 0,
66 USB_CTRL_SET_TIMEOUT);
67
68 usb_autopm_put_interface(port->serial->interface);
69
70 return res;
71}
72
73void usb_wwan_dtr_rts(struct usb_serial_port *port, int on)
74{
75 struct usb_wwan_port_private *portdata;
76 struct usb_wwan_intf_private *intfdata;
77
78 intfdata = usb_get_serial_data(port->serial);
79
80 if (!intfdata->use_send_setup)
81 return;
82
83 portdata = usb_get_serial_port_data(port);
84 /* FIXME: locking */
85 portdata->rts_state = on;
86 portdata->dtr_state = on;
87
88 usb_wwan_send_setup(port);
89}
90EXPORT_SYMBOL(usb_wwan_dtr_rts);
91
92int usb_wwan_tiocmget(struct tty_struct *tty)
93{
94 struct usb_serial_port *port = tty->driver_data;
95 unsigned int value;
96 struct usb_wwan_port_private *portdata;
97
98 portdata = usb_get_serial_port_data(port);
99
100 value = ((portdata->rts_state) ? TIOCM_RTS : 0) |
101 ((portdata->dtr_state) ? TIOCM_DTR : 0) |
102 ((portdata->cts_state) ? TIOCM_CTS : 0) |
103 ((portdata->dsr_state) ? TIOCM_DSR : 0) |
104 ((portdata->dcd_state) ? TIOCM_CAR : 0) |
105 ((portdata->ri_state) ? TIOCM_RNG : 0);
106
107 return value;
108}
109EXPORT_SYMBOL(usb_wwan_tiocmget);
110
111int usb_wwan_tiocmset(struct tty_struct *tty,
112 unsigned int set, unsigned int clear)
113{
114 struct usb_serial_port *port = tty->driver_data;
115 struct usb_wwan_port_private *portdata;
116 struct usb_wwan_intf_private *intfdata;
117
118 portdata = usb_get_serial_port_data(port);
119 intfdata = usb_get_serial_data(port->serial);
120
121 if (!intfdata->use_send_setup)
122 return -EINVAL;
123
124 /* FIXME: what locks portdata fields ? */
125 if (set & TIOCM_RTS)
126 portdata->rts_state = 1;
127 if (set & TIOCM_DTR)
128 portdata->dtr_state = 1;
129
130 if (clear & TIOCM_RTS)
131 portdata->rts_state = 0;
132 if (clear & TIOCM_DTR)
133 portdata->dtr_state = 0;
134 return usb_wwan_send_setup(port);
135}
136EXPORT_SYMBOL(usb_wwan_tiocmset);
137
138static int get_serial_info(struct usb_serial_port *port,
139 struct serial_struct __user *retinfo)
140{
141 struct serial_struct tmp;
142
143 if (!retinfo)
144 return -EFAULT;
145
146 memset(&tmp, 0, sizeof(tmp));
147 tmp.line = port->minor;
148 tmp.port = port->port_number;
149 tmp.baud_base = tty_get_baud_rate(port->port.tty);
150 tmp.close_delay = port->port.close_delay / 10;
151 tmp.closing_wait = port->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
152 ASYNC_CLOSING_WAIT_NONE :
153 port->port.closing_wait / 10;
154
155 if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
156 return -EFAULT;
157 return 0;
158}
159
160static int set_serial_info(struct usb_serial_port *port,
161 struct serial_struct __user *newinfo)
162{
163 struct serial_struct new_serial;
164 unsigned int closing_wait, close_delay;
165 int retval = 0;
166
167 if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
168 return -EFAULT;
169
170 close_delay = new_serial.close_delay * 10;
171 closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
172 ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;
173
174 mutex_lock(&port->port.mutex);
175
176 if (!capable(CAP_SYS_ADMIN)) {
177 if ((close_delay != port->port.close_delay) ||
178 (closing_wait != port->port.closing_wait))
179 retval = -EPERM;
180 else
181 retval = -EOPNOTSUPP;
182 } else {
183 port->port.close_delay = close_delay;
184 port->port.closing_wait = closing_wait;
185 }
186
187 mutex_unlock(&port->port.mutex);
188 return retval;
189}
190
191int usb_wwan_ioctl(struct tty_struct *tty,
192 unsigned int cmd, unsigned long arg)
193{
194 struct usb_serial_port *port = tty->driver_data;
195
196 dev_dbg(&port->dev, "%s cmd 0x%04x\n", __func__, cmd);
197
198 switch (cmd) {
199 case TIOCGSERIAL:
200 return get_serial_info(port,
201 (struct serial_struct __user *) arg);
202 case TIOCSSERIAL:
203 return set_serial_info(port,
204 (struct serial_struct __user *) arg);
205 default:
206 break;
207 }
208
209 dev_dbg(&port->dev, "%s arg not supported\n", __func__);
210
211 return -ENOIOCTLCMD;
212}
213EXPORT_SYMBOL(usb_wwan_ioctl);
214
215int usb_wwan_write(struct tty_struct *tty, struct usb_serial_port *port,
216 const unsigned char *buf, int count)
217{
218 struct usb_wwan_port_private *portdata;
219 struct usb_wwan_intf_private *intfdata;
220 int i;
221 int left, todo;
222 struct urb *this_urb = NULL; /* spurious */
223 int err;
224 unsigned long flags;
225
226 portdata = usb_get_serial_port_data(port);
227 intfdata = usb_get_serial_data(port->serial);
228
229 dev_dbg(&port->dev, "%s: write (%d chars)\n", __func__, count);
230
231 i = 0;
232 left = count;
233 for (i = 0; left > 0 && i < N_OUT_URB; i++) {
234 todo = left;
235 if (todo > OUT_BUFLEN)
236 todo = OUT_BUFLEN;
237
238 this_urb = portdata->out_urbs[i];
239 if (test_and_set_bit(i, &portdata->out_busy)) {
240 if (time_before(jiffies,
241 portdata->tx_start_time[i] + 10 * HZ))
242 continue;
243 usb_unlink_urb(this_urb);
244 continue;
245 }
246 dev_dbg(&port->dev, "%s: endpoint %d buf %d\n", __func__,
247 usb_pipeendpoint(this_urb->pipe), i);
248
249 err = usb_autopm_get_interface_async(port->serial->interface);
250 if (err < 0) {
251 clear_bit(i, &portdata->out_busy);
252 break;
253 }
254
255 /* send the data */
256 memcpy(this_urb->transfer_buffer, buf, todo);
257 this_urb->transfer_buffer_length = todo;
258
259 spin_lock_irqsave(&intfdata->susp_lock, flags);
260 if (intfdata->suspended) {
261 usb_anchor_urb(this_urb, &portdata->delayed);
262 spin_unlock_irqrestore(&intfdata->susp_lock, flags);
263 } else {
264 intfdata->in_flight++;
265 spin_unlock_irqrestore(&intfdata->susp_lock, flags);
266 err = usb_submit_urb(this_urb, GFP_ATOMIC);
267 if (err) {
268 dev_err(&port->dev,
269 "%s: submit urb %d failed: %d\n",
270 __func__, i, err);
271 clear_bit(i, &portdata->out_busy);
272 spin_lock_irqsave(&intfdata->susp_lock, flags);
273 intfdata->in_flight--;
274 spin_unlock_irqrestore(&intfdata->susp_lock,
275 flags);
276 usb_autopm_put_interface_async(port->serial->interface);
277 break;
278 }
279 }
280
281 portdata->tx_start_time[i] = jiffies;
282 buf += todo;
283 left -= todo;
284 }
285
286 count -= left;
287 dev_dbg(&port->dev, "%s: wrote (did %d)\n", __func__, count);
288 return count;
289}
290EXPORT_SYMBOL(usb_wwan_write);
291
292static void usb_wwan_indat_callback(struct urb *urb)
293{
294 int err;
295 int endpoint;
296 struct usb_serial_port *port;
297 struct device *dev;
298 unsigned char *data = urb->transfer_buffer;
299 int status = urb->status;
300
301 endpoint = usb_pipeendpoint(urb->pipe);
302 port = urb->context;
303 dev = &port->dev;
304
305 if (status) {
306 dev_dbg(dev, "%s: nonzero status: %d on endpoint %02x.\n",
307 __func__, status, endpoint);
308 } else {
309 if (urb->actual_length) {
310 tty_insert_flip_string(&port->port, data,
311 urb->actual_length);
312 tty_flip_buffer_push(&port->port);
313 } else
314 dev_dbg(dev, "%s: empty read urb received\n", __func__);
315 }
316 /* Resubmit urb so we continue receiving */
317 err = usb_submit_urb(urb, GFP_ATOMIC);
318 if (err) {
319 if (err != -EPERM && err != -ENODEV) {
320 dev_err(dev, "%s: resubmit read urb failed. (%d)\n",
321 __func__, err);
322 /* busy also in error unless we are killed */
323 usb_mark_last_busy(port->serial->dev);
324 }
325 } else {
326 usb_mark_last_busy(port->serial->dev);
327 }
328}
329
330static void usb_wwan_outdat_callback(struct urb *urb)
331{
332 struct usb_serial_port *port;
333 struct usb_wwan_port_private *portdata;
334 struct usb_wwan_intf_private *intfdata;
335 int i;
336
337 port = urb->context;
338 intfdata = usb_get_serial_data(port->serial);
339
340 usb_serial_port_softint(port);
341 usb_autopm_put_interface_async(port->serial->interface);
342 portdata = usb_get_serial_port_data(port);
343 spin_lock(&intfdata->susp_lock);
344 intfdata->in_flight--;
345 spin_unlock(&intfdata->susp_lock);
346
347 for (i = 0; i < N_OUT_URB; ++i) {
348 if (portdata->out_urbs[i] == urb) {
349 smp_mb__before_atomic();
350 clear_bit(i, &portdata->out_busy);
351 break;
352 }
353 }
354}
355
356int usb_wwan_write_room(struct tty_struct *tty)
357{
358 struct usb_serial_port *port = tty->driver_data;
359 struct usb_wwan_port_private *portdata;
360 int i;
361 int data_len = 0;
362 struct urb *this_urb;
363
364 portdata = usb_get_serial_port_data(port);
365
366 for (i = 0; i < N_OUT_URB; i++) {
367 this_urb = portdata->out_urbs[i];
368 if (this_urb && !test_bit(i, &portdata->out_busy))
369 data_len += OUT_BUFLEN;
370 }
371
372 dev_dbg(&port->dev, "%s: %d\n", __func__, data_len);
373 return data_len;
374}
375EXPORT_SYMBOL(usb_wwan_write_room);
376
377int usb_wwan_chars_in_buffer(struct tty_struct *tty)
378{
379 struct usb_serial_port *port = tty->driver_data;
380 struct usb_wwan_port_private *portdata;
381 int i;
382 int data_len = 0;
383 struct urb *this_urb;
384
385 portdata = usb_get_serial_port_data(port);
386
387 for (i = 0; i < N_OUT_URB; i++) {
388 this_urb = portdata->out_urbs[i];
389 /* FIXME: This locking is insufficient as this_urb may
390 go unused during the test */
391 if (this_urb && test_bit(i, &portdata->out_busy))
392 data_len += this_urb->transfer_buffer_length;
393 }
394 dev_dbg(&port->dev, "%s: %d\n", __func__, data_len);
395 return data_len;
396}
397EXPORT_SYMBOL(usb_wwan_chars_in_buffer);
398
399int usb_wwan_open(struct tty_struct *tty, struct usb_serial_port *port)
400{
401 struct usb_wwan_port_private *portdata;
402 struct usb_wwan_intf_private *intfdata;
403 struct usb_serial *serial = port->serial;
404 int i, err;
405 struct urb *urb;
406
407 portdata = usb_get_serial_port_data(port);
408 intfdata = usb_get_serial_data(serial);
409
410 if (port->interrupt_in_urb) {
411 err = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
412 if (err) {
413 dev_err(&port->dev, "%s: submit int urb failed: %d\n",
414 __func__, err);
415 }
416 }
417
418 /* Start reading from the IN endpoint */
419 for (i = 0; i < N_IN_URB; i++) {
420 urb = portdata->in_urbs[i];
421 if (!urb)
422 continue;
423 err = usb_submit_urb(urb, GFP_KERNEL);
424 if (err) {
425 dev_err(&port->dev,
426 "%s: submit read urb %d failed: %d\n",
427 __func__, i, err);
428 }
429 }
430
431 spin_lock_irq(&intfdata->susp_lock);
432 if (++intfdata->open_ports == 1)
433 serial->interface->needs_remote_wakeup = 1;
434 spin_unlock_irq(&intfdata->susp_lock);
435 /* this balances a get in the generic USB serial code */
436 usb_autopm_put_interface(serial->interface);
437
438 return 0;
439}
440EXPORT_SYMBOL(usb_wwan_open);
441
442static void unbusy_queued_urb(struct urb *urb,
443 struct usb_wwan_port_private *portdata)
444{
445 int i;
446
447 for (i = 0; i < N_OUT_URB; i++) {
448 if (urb == portdata->out_urbs[i]) {
449 clear_bit(i, &portdata->out_busy);
450 break;
451 }
452 }
453}
454
455void usb_wwan_close(struct usb_serial_port *port)
456{
457 int i;
458 struct usb_serial *serial = port->serial;
459 struct usb_wwan_port_private *portdata;
460 struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
461 struct urb *urb;
462
463 portdata = usb_get_serial_port_data(port);
464
465 /*
466 * Need to take susp_lock to make sure port is not already being
467 * resumed, but no need to hold it due to ASYNC_INITIALIZED.
468 */
469 spin_lock_irq(&intfdata->susp_lock);
470 if (--intfdata->open_ports == 0)
471 serial->interface->needs_remote_wakeup = 0;
472 spin_unlock_irq(&intfdata->susp_lock);
473
474 for (;;) {
475 urb = usb_get_from_anchor(&portdata->delayed);
476 if (!urb)
477 break;
478 unbusy_queued_urb(urb, portdata);
479 usb_autopm_put_interface_async(serial->interface);
480 }
481
482 for (i = 0; i < N_IN_URB; i++)
483 usb_kill_urb(portdata->in_urbs[i]);
484 for (i = 0; i < N_OUT_URB; i++)
485 usb_kill_urb(portdata->out_urbs[i]);
486 usb_kill_urb(port->interrupt_in_urb);
487
488 usb_autopm_get_interface_no_resume(serial->interface);
489}
490EXPORT_SYMBOL(usb_wwan_close);
491
492static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
493 int endpoint,
494 int dir, void *ctx, char *buf, int len,
495 void (*callback) (struct urb *))
496{
497 struct usb_serial *serial = port->serial;
498 struct urb *urb;
499
500 urb = usb_alloc_urb(0, GFP_KERNEL); /* No ISO */
501 if (!urb)
502 return NULL;
503
504 usb_fill_bulk_urb(urb, serial->dev,
505 usb_sndbulkpipe(serial->dev, endpoint) | dir,
506 buf, len, callback, ctx);
507
508 return urb;
509}
510
511int usb_wwan_port_probe(struct usb_serial_port *port)
512{
513 struct usb_wwan_port_private *portdata;
514 struct urb *urb;
515 u8 *buffer;
516 int i;
517
518 if (!port->bulk_in_size || !port->bulk_out_size)
519 return -ENODEV;
520
521 portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
522 if (!portdata)
523 return -ENOMEM;
524
525 init_usb_anchor(&portdata->delayed);
526
527 for (i = 0; i < N_IN_URB; i++) {
528 buffer = (u8 *)__get_free_page(GFP_KERNEL);
529 if (!buffer)
530 goto bail_out_error;
531 portdata->in_buffer[i] = buffer;
532
533 urb = usb_wwan_setup_urb(port, port->bulk_in_endpointAddress,
534 USB_DIR_IN, port,
535 buffer, IN_BUFLEN,
536 usb_wwan_indat_callback);
537 portdata->in_urbs[i] = urb;
538 }
539
540 for (i = 0; i < N_OUT_URB; i++) {
541 buffer = kmalloc(OUT_BUFLEN, GFP_KERNEL);
542 if (!buffer)
543 goto bail_out_error2;
544 portdata->out_buffer[i] = buffer;
545
546 urb = usb_wwan_setup_urb(port, port->bulk_out_endpointAddress,
547 USB_DIR_OUT, port,
548 buffer, OUT_BUFLEN,
549 usb_wwan_outdat_callback);
550 portdata->out_urbs[i] = urb;
551 }
552
553 usb_set_serial_port_data(port, portdata);
554
555 return 0;
556
557bail_out_error2:
558 for (i = 0; i < N_OUT_URB; i++) {
559 usb_free_urb(portdata->out_urbs[i]);
560 kfree(portdata->out_buffer[i]);
561 }
562bail_out_error:
563 for (i = 0; i < N_IN_URB; i++) {
564 usb_free_urb(portdata->in_urbs[i]);
565 free_page((unsigned long)portdata->in_buffer[i]);
566 }
567 kfree(portdata);
568
569 return -ENOMEM;
570}
571EXPORT_SYMBOL_GPL(usb_wwan_port_probe);
572
573int usb_wwan_port_remove(struct usb_serial_port *port)
574{
575 int i;
576 struct usb_wwan_port_private *portdata;
577
578 portdata = usb_get_serial_port_data(port);
579 usb_set_serial_port_data(port, NULL);
580
581 for (i = 0; i < N_IN_URB; i++) {
582 usb_free_urb(portdata->in_urbs[i]);
583 free_page((unsigned long)portdata->in_buffer[i]);
584 }
585 for (i = 0; i < N_OUT_URB; i++) {
586 usb_free_urb(portdata->out_urbs[i]);
587 kfree(portdata->out_buffer[i]);
588 }
589
590 kfree(portdata);
591
592 return 0;
593}
594EXPORT_SYMBOL(usb_wwan_port_remove);
595
596#ifdef CONFIG_PM
597static void stop_urbs(struct usb_serial *serial)
598{
599 int i, j;
600 struct usb_serial_port *port;
601 struct usb_wwan_port_private *portdata;
602
603 for (i = 0; i < serial->num_ports; ++i) {
604 port = serial->port[i];
605 portdata = usb_get_serial_port_data(port);
606 if (!portdata)
607 continue;
608 for (j = 0; j < N_IN_URB; j++)
609 usb_kill_urb(portdata->in_urbs[j]);
610 for (j = 0; j < N_OUT_URB; j++)
611 usb_kill_urb(portdata->out_urbs[j]);
612 usb_kill_urb(port->interrupt_in_urb);
613 }
614}
615
616int usb_wwan_suspend(struct usb_serial *serial, pm_message_t message)
617{
618 struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
619
620 spin_lock_irq(&intfdata->susp_lock);
621 if (PMSG_IS_AUTO(message)) {
622 if (intfdata->in_flight) {
623 spin_unlock_irq(&intfdata->susp_lock);
624 return -EBUSY;
625 }
626 }
627 intfdata->suspended = 1;
628 spin_unlock_irq(&intfdata->susp_lock);
629
630 stop_urbs(serial);
631
632 return 0;
633}
634EXPORT_SYMBOL(usb_wwan_suspend);
635
636/* Caller must hold susp_lock. */
637static int usb_wwan_submit_delayed_urbs(struct usb_serial_port *port)
638{
639 struct usb_serial *serial = port->serial;
640 struct usb_wwan_intf_private *data = usb_get_serial_data(serial);
641 struct usb_wwan_port_private *portdata;
642 struct urb *urb;
643 int err_count = 0;
644 int err;
645
646 portdata = usb_get_serial_port_data(port);
647
648 for (;;) {
649 urb = usb_get_from_anchor(&portdata->delayed);
650 if (!urb)
651 break;
652
653 err = usb_submit_urb(urb, GFP_ATOMIC);
654 if (err) {
655 dev_err(&port->dev, "%s: submit urb failed: %d\n",
656 __func__, err);
657 err_count++;
658 unbusy_queued_urb(urb, portdata);
659 usb_autopm_put_interface_async(serial->interface);
660 continue;
661 }
662 data->in_flight++;
663 }
664
665 if (err_count)
666 return -EIO;
667
668 return 0;
669}
670
671int usb_wwan_resume(struct usb_serial *serial)
672{
673 int i, j;
674 struct usb_serial_port *port;
675 struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
676 struct usb_wwan_port_private *portdata;
677 struct urb *urb;
678 int err;
679 int err_count = 0;
680
681 spin_lock_irq(&intfdata->susp_lock);
682 for (i = 0; i < serial->num_ports; i++) {
683 port = serial->port[i];
684
685 if (!test_bit(ASYNCB_INITIALIZED, &port->port.flags))
686 continue;
687
688 portdata = usb_get_serial_port_data(port);
689
690 if (port->interrupt_in_urb) {
691 err = usb_submit_urb(port->interrupt_in_urb,
692 GFP_ATOMIC);
693 if (err) {
694 dev_err(&port->dev,
695 "%s: submit int urb failed: %d\n",
696 __func__, err);
697 err_count++;
698 }
699 }
700
701 err = usb_wwan_submit_delayed_urbs(port);
702 if (err)
703 err_count++;
704
705 for (j = 0; j < N_IN_URB; j++) {
706 urb = portdata->in_urbs[j];
707 err = usb_submit_urb(urb, GFP_ATOMIC);
708 if (err < 0) {
709 dev_err(&port->dev,
710 "%s: submit read urb %d failed: %d\n",
711 __func__, i, err);
712 err_count++;
713 }
714 }
715 }
716 intfdata->suspended = 0;
717 spin_unlock_irq(&intfdata->susp_lock);
718
719 if (err_count)
720 return -EIO;
721
722 return 0;
723}
724EXPORT_SYMBOL(usb_wwan_resume);
725#endif
726
727MODULE_AUTHOR(DRIVER_AUTHOR);
728MODULE_DESCRIPTION(DRIVER_DESC);
729MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0
2/*
3 USB Driver layer for GSM modems
4
5 Copyright (C) 2005 Matthias Urlichs <smurf@smurf.noris.de>
6
7 Portions copied from the Keyspan driver by Hugh Blemings <hugh@blemings.org>
8
9 History: see the git log.
10
11 Work sponsored by: Sigos GmbH, Germany <info@sigos.de>
12
13 This driver exists because the "normal" serial driver doesn't work too well
14 with GSM modems. Issues:
15 - data loss -- one single Receive URB is not nearly enough
16 - controlling the baud rate doesn't make sense
17*/
18
19#define DRIVER_AUTHOR "Matthias Urlichs <smurf@smurf.noris.de>"
20#define DRIVER_DESC "USB Driver for GSM modems"
21
22#include <linux/kernel.h>
23#include <linux/jiffies.h>
24#include <linux/errno.h>
25#include <linux/slab.h>
26#include <linux/tty.h>
27#include <linux/tty_flip.h>
28#include <linux/module.h>
29#include <linux/bitops.h>
30#include <linux/uaccess.h>
31#include <linux/usb.h>
32#include <linux/usb/cdc.h>
33#include <linux/usb/serial.h>
34#include <linux/serial.h>
35#include "usb-wwan.h"
36
37/*
38 * Generate DTR/RTS signals on the port using the SET_CONTROL_LINE_STATE request
39 * in CDC ACM.
40 */
41static int usb_wwan_send_setup(struct usb_serial_port *port)
42{
43 struct usb_serial *serial = port->serial;
44 struct usb_wwan_port_private *portdata;
45 int val = 0;
46 int ifnum;
47 int res;
48
49 portdata = usb_get_serial_port_data(port);
50
51 if (portdata->dtr_state)
52 val |= USB_CDC_CTRL_DTR;
53 if (portdata->rts_state)
54 val |= USB_CDC_CTRL_RTS;
55
56 ifnum = serial->interface->cur_altsetting->desc.bInterfaceNumber;
57
58 res = usb_autopm_get_interface(serial->interface);
59 if (res)
60 return res;
61
62 res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
63 USB_CDC_REQ_SET_CONTROL_LINE_STATE,
64 USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
65 val, ifnum, NULL, 0, USB_CTRL_SET_TIMEOUT);
66
67 usb_autopm_put_interface(port->serial->interface);
68
69 return res;
70}
71
72void usb_wwan_dtr_rts(struct usb_serial_port *port, int on)
73{
74 struct usb_wwan_port_private *portdata;
75 struct usb_wwan_intf_private *intfdata;
76
77 intfdata = usb_get_serial_data(port->serial);
78
79 if (!intfdata->use_send_setup)
80 return;
81
82 portdata = usb_get_serial_port_data(port);
83 /* FIXME: locking */
84 portdata->rts_state = on;
85 portdata->dtr_state = on;
86
87 usb_wwan_send_setup(port);
88}
89EXPORT_SYMBOL(usb_wwan_dtr_rts);
90
91int usb_wwan_tiocmget(struct tty_struct *tty)
92{
93 struct usb_serial_port *port = tty->driver_data;
94 unsigned int value;
95 struct usb_wwan_port_private *portdata;
96
97 portdata = usb_get_serial_port_data(port);
98
99 value = ((portdata->rts_state) ? TIOCM_RTS : 0) |
100 ((portdata->dtr_state) ? TIOCM_DTR : 0) |
101 ((portdata->cts_state) ? TIOCM_CTS : 0) |
102 ((portdata->dsr_state) ? TIOCM_DSR : 0) |
103 ((portdata->dcd_state) ? TIOCM_CAR : 0) |
104 ((portdata->ri_state) ? TIOCM_RNG : 0);
105
106 return value;
107}
108EXPORT_SYMBOL(usb_wwan_tiocmget);
109
110int usb_wwan_tiocmset(struct tty_struct *tty,
111 unsigned int set, unsigned int clear)
112{
113 struct usb_serial_port *port = tty->driver_data;
114 struct usb_wwan_port_private *portdata;
115 struct usb_wwan_intf_private *intfdata;
116
117 portdata = usb_get_serial_port_data(port);
118 intfdata = usb_get_serial_data(port->serial);
119
120 if (!intfdata->use_send_setup)
121 return -EINVAL;
122
123 /* FIXME: what locks portdata fields ? */
124 if (set & TIOCM_RTS)
125 portdata->rts_state = 1;
126 if (set & TIOCM_DTR)
127 portdata->dtr_state = 1;
128
129 if (clear & TIOCM_RTS)
130 portdata->rts_state = 0;
131 if (clear & TIOCM_DTR)
132 portdata->dtr_state = 0;
133 return usb_wwan_send_setup(port);
134}
135EXPORT_SYMBOL(usb_wwan_tiocmset);
136
137int usb_wwan_write(struct tty_struct *tty, struct usb_serial_port *port,
138 const unsigned char *buf, int count)
139{
140 struct usb_wwan_port_private *portdata;
141 struct usb_wwan_intf_private *intfdata;
142 int i;
143 int left, todo;
144 struct urb *this_urb = NULL; /* spurious */
145 int err;
146 unsigned long flags;
147
148 portdata = usb_get_serial_port_data(port);
149 intfdata = usb_get_serial_data(port->serial);
150
151 dev_dbg(&port->dev, "%s: write (%d chars)\n", __func__, count);
152
153 left = count;
154 for (i = 0; left > 0 && i < N_OUT_URB; i++) {
155 todo = left;
156 if (todo > OUT_BUFLEN)
157 todo = OUT_BUFLEN;
158
159 this_urb = portdata->out_urbs[i];
160 if (test_and_set_bit(i, &portdata->out_busy)) {
161 if (time_before(jiffies,
162 portdata->tx_start_time[i] + 10 * HZ))
163 continue;
164 usb_unlink_urb(this_urb);
165 continue;
166 }
167 dev_dbg(&port->dev, "%s: endpoint %d buf %d\n", __func__,
168 usb_pipeendpoint(this_urb->pipe), i);
169
170 err = usb_autopm_get_interface_async(port->serial->interface);
171 if (err < 0) {
172 clear_bit(i, &portdata->out_busy);
173 break;
174 }
175
176 /* send the data */
177 memcpy(this_urb->transfer_buffer, buf, todo);
178 this_urb->transfer_buffer_length = todo;
179
180 spin_lock_irqsave(&intfdata->susp_lock, flags);
181 if (intfdata->suspended) {
182 usb_anchor_urb(this_urb, &portdata->delayed);
183 spin_unlock_irqrestore(&intfdata->susp_lock, flags);
184 } else {
185 intfdata->in_flight++;
186 spin_unlock_irqrestore(&intfdata->susp_lock, flags);
187 err = usb_submit_urb(this_urb, GFP_ATOMIC);
188 if (err) {
189 dev_err(&port->dev,
190 "%s: submit urb %d failed: %d\n",
191 __func__, i, err);
192 clear_bit(i, &portdata->out_busy);
193 spin_lock_irqsave(&intfdata->susp_lock, flags);
194 intfdata->in_flight--;
195 spin_unlock_irqrestore(&intfdata->susp_lock,
196 flags);
197 usb_autopm_put_interface_async(port->serial->interface);
198 break;
199 }
200 }
201
202 portdata->tx_start_time[i] = jiffies;
203 buf += todo;
204 left -= todo;
205 }
206
207 count -= left;
208 dev_dbg(&port->dev, "%s: wrote (did %d)\n", __func__, count);
209 return count;
210}
211EXPORT_SYMBOL(usb_wwan_write);
212
213static void usb_wwan_indat_callback(struct urb *urb)
214{
215 int err;
216 int endpoint;
217 struct usb_serial_port *port;
218 struct device *dev;
219 unsigned char *data = urb->transfer_buffer;
220 int status = urb->status;
221
222 endpoint = usb_pipeendpoint(urb->pipe);
223 port = urb->context;
224 dev = &port->dev;
225
226 if (status) {
227 dev_dbg(dev, "%s: nonzero status: %d on endpoint %02x.\n",
228 __func__, status, endpoint);
229
230 /* don't resubmit on fatal errors */
231 if (status == -ESHUTDOWN || status == -ENOENT)
232 return;
233 } else {
234 if (urb->actual_length) {
235 tty_insert_flip_string(&port->port, data,
236 urb->actual_length);
237 tty_flip_buffer_push(&port->port);
238 } else
239 dev_dbg(dev, "%s: empty read urb received\n", __func__);
240 }
241 /* Resubmit urb so we continue receiving */
242 err = usb_submit_urb(urb, GFP_ATOMIC);
243 if (err) {
244 if (err != -EPERM && err != -ENODEV) {
245 dev_err(dev, "%s: resubmit read urb failed. (%d)\n",
246 __func__, err);
247 /* busy also in error unless we are killed */
248 usb_mark_last_busy(port->serial->dev);
249 }
250 } else {
251 usb_mark_last_busy(port->serial->dev);
252 }
253}
254
255static void usb_wwan_outdat_callback(struct urb *urb)
256{
257 struct usb_serial_port *port;
258 struct usb_wwan_port_private *portdata;
259 struct usb_wwan_intf_private *intfdata;
260 unsigned long flags;
261 int i;
262
263 port = urb->context;
264 intfdata = usb_get_serial_data(port->serial);
265
266 usb_serial_port_softint(port);
267 usb_autopm_put_interface_async(port->serial->interface);
268 portdata = usb_get_serial_port_data(port);
269 spin_lock_irqsave(&intfdata->susp_lock, flags);
270 intfdata->in_flight--;
271 spin_unlock_irqrestore(&intfdata->susp_lock, flags);
272
273 for (i = 0; i < N_OUT_URB; ++i) {
274 if (portdata->out_urbs[i] == urb) {
275 smp_mb__before_atomic();
276 clear_bit(i, &portdata->out_busy);
277 break;
278 }
279 }
280}
281
282unsigned int usb_wwan_write_room(struct tty_struct *tty)
283{
284 struct usb_serial_port *port = tty->driver_data;
285 struct usb_wwan_port_private *portdata;
286 int i;
287 unsigned int data_len = 0;
288 struct urb *this_urb;
289
290 portdata = usb_get_serial_port_data(port);
291
292 for (i = 0; i < N_OUT_URB; i++) {
293 this_urb = portdata->out_urbs[i];
294 if (this_urb && !test_bit(i, &portdata->out_busy))
295 data_len += OUT_BUFLEN;
296 }
297
298 dev_dbg(&port->dev, "%s: %u\n", __func__, data_len);
299 return data_len;
300}
301EXPORT_SYMBOL(usb_wwan_write_room);
302
303unsigned int usb_wwan_chars_in_buffer(struct tty_struct *tty)
304{
305 struct usb_serial_port *port = tty->driver_data;
306 struct usb_wwan_port_private *portdata;
307 int i;
308 unsigned int data_len = 0;
309 struct urb *this_urb;
310
311 portdata = usb_get_serial_port_data(port);
312
313 for (i = 0; i < N_OUT_URB; i++) {
314 this_urb = portdata->out_urbs[i];
315 /* FIXME: This locking is insufficient as this_urb may
316 go unused during the test */
317 if (this_urb && test_bit(i, &portdata->out_busy))
318 data_len += this_urb->transfer_buffer_length;
319 }
320 dev_dbg(&port->dev, "%s: %u\n", __func__, data_len);
321 return data_len;
322}
323EXPORT_SYMBOL(usb_wwan_chars_in_buffer);
324
325int usb_wwan_open(struct tty_struct *tty, struct usb_serial_port *port)
326{
327 struct usb_wwan_port_private *portdata;
328 struct usb_wwan_intf_private *intfdata;
329 struct usb_serial *serial = port->serial;
330 int i, err;
331 struct urb *urb;
332
333 portdata = usb_get_serial_port_data(port);
334 intfdata = usb_get_serial_data(serial);
335
336 if (port->interrupt_in_urb) {
337 err = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
338 if (err) {
339 dev_err(&port->dev, "%s: submit int urb failed: %d\n",
340 __func__, err);
341 }
342 }
343
344 /* Start reading from the IN endpoint */
345 for (i = 0; i < N_IN_URB; i++) {
346 urb = portdata->in_urbs[i];
347 if (!urb)
348 continue;
349 err = usb_submit_urb(urb, GFP_KERNEL);
350 if (err) {
351 dev_err(&port->dev,
352 "%s: submit read urb %d failed: %d\n",
353 __func__, i, err);
354 }
355 }
356
357 spin_lock_irq(&intfdata->susp_lock);
358 if (++intfdata->open_ports == 1)
359 serial->interface->needs_remote_wakeup = 1;
360 spin_unlock_irq(&intfdata->susp_lock);
361 /* this balances a get in the generic USB serial code */
362 usb_autopm_put_interface(serial->interface);
363
364 return 0;
365}
366EXPORT_SYMBOL(usb_wwan_open);
367
368static void unbusy_queued_urb(struct urb *urb,
369 struct usb_wwan_port_private *portdata)
370{
371 int i;
372
373 for (i = 0; i < N_OUT_URB; i++) {
374 if (urb == portdata->out_urbs[i]) {
375 clear_bit(i, &portdata->out_busy);
376 break;
377 }
378 }
379}
380
381void usb_wwan_close(struct usb_serial_port *port)
382{
383 int i;
384 struct usb_serial *serial = port->serial;
385 struct usb_wwan_port_private *portdata;
386 struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
387 struct urb *urb;
388
389 portdata = usb_get_serial_port_data(port);
390
391 /*
392 * Need to take susp_lock to make sure port is not already being
393 * resumed, but no need to hold it due to the tty-port initialized
394 * flag.
395 */
396 spin_lock_irq(&intfdata->susp_lock);
397 if (--intfdata->open_ports == 0)
398 serial->interface->needs_remote_wakeup = 0;
399 spin_unlock_irq(&intfdata->susp_lock);
400
401 for (;;) {
402 urb = usb_get_from_anchor(&portdata->delayed);
403 if (!urb)
404 break;
405 unbusy_queued_urb(urb, portdata);
406 usb_autopm_put_interface_async(serial->interface);
407 }
408
409 for (i = 0; i < N_IN_URB; i++)
410 usb_kill_urb(portdata->in_urbs[i]);
411 for (i = 0; i < N_OUT_URB; i++)
412 usb_kill_urb(portdata->out_urbs[i]);
413 usb_kill_urb(port->interrupt_in_urb);
414
415 usb_autopm_get_interface_no_resume(serial->interface);
416}
417EXPORT_SYMBOL(usb_wwan_close);
418
419static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
420 int endpoint,
421 int dir, void *ctx, char *buf, int len,
422 void (*callback) (struct urb *))
423{
424 struct usb_serial *serial = port->serial;
425 struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
426 struct urb *urb;
427
428 urb = usb_alloc_urb(0, GFP_KERNEL); /* No ISO */
429 if (!urb)
430 return NULL;
431
432 usb_fill_bulk_urb(urb, serial->dev,
433 usb_sndbulkpipe(serial->dev, endpoint) | dir,
434 buf, len, callback, ctx);
435
436 if (intfdata->use_zlp && dir == USB_DIR_OUT)
437 urb->transfer_flags |= URB_ZERO_PACKET;
438
439 return urb;
440}
441
442int usb_wwan_port_probe(struct usb_serial_port *port)
443{
444 struct usb_wwan_port_private *portdata;
445 struct urb *urb;
446 u8 *buffer;
447 int i;
448
449 if (!port->bulk_in_size || !port->bulk_out_size)
450 return -ENODEV;
451
452 portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
453 if (!portdata)
454 return -ENOMEM;
455
456 init_usb_anchor(&portdata->delayed);
457
458 for (i = 0; i < N_IN_URB; i++) {
459 buffer = (u8 *)__get_free_page(GFP_KERNEL);
460 if (!buffer)
461 goto bail_out_error;
462 portdata->in_buffer[i] = buffer;
463
464 urb = usb_wwan_setup_urb(port, port->bulk_in_endpointAddress,
465 USB_DIR_IN, port,
466 buffer, IN_BUFLEN,
467 usb_wwan_indat_callback);
468 portdata->in_urbs[i] = urb;
469 }
470
471 for (i = 0; i < N_OUT_URB; i++) {
472 buffer = kmalloc(OUT_BUFLEN, GFP_KERNEL);
473 if (!buffer)
474 goto bail_out_error2;
475 portdata->out_buffer[i] = buffer;
476
477 urb = usb_wwan_setup_urb(port, port->bulk_out_endpointAddress,
478 USB_DIR_OUT, port,
479 buffer, OUT_BUFLEN,
480 usb_wwan_outdat_callback);
481 portdata->out_urbs[i] = urb;
482 }
483
484 usb_set_serial_port_data(port, portdata);
485
486 return 0;
487
488bail_out_error2:
489 for (i = 0; i < N_OUT_URB; i++) {
490 usb_free_urb(portdata->out_urbs[i]);
491 kfree(portdata->out_buffer[i]);
492 }
493bail_out_error:
494 for (i = 0; i < N_IN_URB; i++) {
495 usb_free_urb(portdata->in_urbs[i]);
496 free_page((unsigned long)portdata->in_buffer[i]);
497 }
498 kfree(portdata);
499
500 return -ENOMEM;
501}
502EXPORT_SYMBOL_GPL(usb_wwan_port_probe);
503
504void usb_wwan_port_remove(struct usb_serial_port *port)
505{
506 int i;
507 struct usb_wwan_port_private *portdata;
508
509 portdata = usb_get_serial_port_data(port);
510 usb_set_serial_port_data(port, NULL);
511
512 for (i = 0; i < N_IN_URB; i++) {
513 usb_free_urb(portdata->in_urbs[i]);
514 free_page((unsigned long)portdata->in_buffer[i]);
515 }
516 for (i = 0; i < N_OUT_URB; i++) {
517 usb_free_urb(portdata->out_urbs[i]);
518 kfree(portdata->out_buffer[i]);
519 }
520
521 kfree(portdata);
522}
523EXPORT_SYMBOL(usb_wwan_port_remove);
524
525#ifdef CONFIG_PM
526static void stop_urbs(struct usb_serial *serial)
527{
528 int i, j;
529 struct usb_serial_port *port;
530 struct usb_wwan_port_private *portdata;
531
532 for (i = 0; i < serial->num_ports; ++i) {
533 port = serial->port[i];
534 portdata = usb_get_serial_port_data(port);
535 if (!portdata)
536 continue;
537 for (j = 0; j < N_IN_URB; j++)
538 usb_kill_urb(portdata->in_urbs[j]);
539 for (j = 0; j < N_OUT_URB; j++)
540 usb_kill_urb(portdata->out_urbs[j]);
541 usb_kill_urb(port->interrupt_in_urb);
542 }
543}
544
545int usb_wwan_suspend(struct usb_serial *serial, pm_message_t message)
546{
547 struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
548
549 spin_lock_irq(&intfdata->susp_lock);
550 if (PMSG_IS_AUTO(message)) {
551 if (intfdata->in_flight) {
552 spin_unlock_irq(&intfdata->susp_lock);
553 return -EBUSY;
554 }
555 }
556 intfdata->suspended = 1;
557 spin_unlock_irq(&intfdata->susp_lock);
558
559 stop_urbs(serial);
560
561 return 0;
562}
563EXPORT_SYMBOL(usb_wwan_suspend);
564
565/* Caller must hold susp_lock. */
566static int usb_wwan_submit_delayed_urbs(struct usb_serial_port *port)
567{
568 struct usb_serial *serial = port->serial;
569 struct usb_wwan_intf_private *data = usb_get_serial_data(serial);
570 struct usb_wwan_port_private *portdata;
571 struct urb *urb;
572 int err_count = 0;
573 int err;
574
575 portdata = usb_get_serial_port_data(port);
576
577 for (;;) {
578 urb = usb_get_from_anchor(&portdata->delayed);
579 if (!urb)
580 break;
581
582 err = usb_submit_urb(urb, GFP_ATOMIC);
583 if (err) {
584 dev_err(&port->dev, "%s: submit urb failed: %d\n",
585 __func__, err);
586 err_count++;
587 unbusy_queued_urb(urb, portdata);
588 usb_autopm_put_interface_async(serial->interface);
589 continue;
590 }
591 data->in_flight++;
592 }
593
594 if (err_count)
595 return -EIO;
596
597 return 0;
598}
599
600int usb_wwan_resume(struct usb_serial *serial)
601{
602 int i, j;
603 struct usb_serial_port *port;
604 struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
605 struct usb_wwan_port_private *portdata;
606 struct urb *urb;
607 int err;
608 int err_count = 0;
609
610 spin_lock_irq(&intfdata->susp_lock);
611 for (i = 0; i < serial->num_ports; i++) {
612 port = serial->port[i];
613
614 if (!tty_port_initialized(&port->port))
615 continue;
616
617 portdata = usb_get_serial_port_data(port);
618
619 if (port->interrupt_in_urb) {
620 err = usb_submit_urb(port->interrupt_in_urb,
621 GFP_ATOMIC);
622 if (err) {
623 dev_err(&port->dev,
624 "%s: submit int urb failed: %d\n",
625 __func__, err);
626 err_count++;
627 }
628 }
629
630 err = usb_wwan_submit_delayed_urbs(port);
631 if (err)
632 err_count++;
633
634 for (j = 0; j < N_IN_URB; j++) {
635 urb = portdata->in_urbs[j];
636 err = usb_submit_urb(urb, GFP_ATOMIC);
637 if (err < 0) {
638 dev_err(&port->dev,
639 "%s: submit read urb %d failed: %d\n",
640 __func__, i, err);
641 err_count++;
642 }
643 }
644 }
645 intfdata->suspended = 0;
646 spin_unlock_irq(&intfdata->susp_lock);
647
648 if (err_count)
649 return -EIO;
650
651 return 0;
652}
653EXPORT_SYMBOL(usb_wwan_resume);
654#endif
655
656MODULE_AUTHOR(DRIVER_AUTHOR);
657MODULE_DESCRIPTION(DRIVER_DESC);
658MODULE_LICENSE("GPL v2");