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