xref: /linux/drivers/usb/serial/usb_wwan.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
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 void usb_wwan_dtr_rts(struct usb_serial_port *port, int on)
40 {
41 	struct usb_wwan_port_private *portdata;
42 	struct usb_wwan_intf_private *intfdata;
43 
44 	intfdata = usb_get_serial_data(port->serial);
45 
46 	if (!intfdata->send_setup)
47 		return;
48 
49 	portdata = usb_get_serial_port_data(port);
50 	/* FIXME: locking */
51 	portdata->rts_state = on;
52 	portdata->dtr_state = on;
53 
54 	intfdata->send_setup(port);
55 }
56 EXPORT_SYMBOL(usb_wwan_dtr_rts);
57 
58 int usb_wwan_tiocmget(struct tty_struct *tty)
59 {
60 	struct usb_serial_port *port = tty->driver_data;
61 	unsigned int value;
62 	struct usb_wwan_port_private *portdata;
63 
64 	portdata = usb_get_serial_port_data(port);
65 
66 	value = ((portdata->rts_state) ? TIOCM_RTS : 0) |
67 	    ((portdata->dtr_state) ? TIOCM_DTR : 0) |
68 	    ((portdata->cts_state) ? TIOCM_CTS : 0) |
69 	    ((portdata->dsr_state) ? TIOCM_DSR : 0) |
70 	    ((portdata->dcd_state) ? TIOCM_CAR : 0) |
71 	    ((portdata->ri_state) ? TIOCM_RNG : 0);
72 
73 	return value;
74 }
75 EXPORT_SYMBOL(usb_wwan_tiocmget);
76 
77 int usb_wwan_tiocmset(struct tty_struct *tty,
78 		      unsigned int set, unsigned int clear)
79 {
80 	struct usb_serial_port *port = tty->driver_data;
81 	struct usb_wwan_port_private *portdata;
82 	struct usb_wwan_intf_private *intfdata;
83 
84 	portdata = usb_get_serial_port_data(port);
85 	intfdata = usb_get_serial_data(port->serial);
86 
87 	if (!intfdata->send_setup)
88 		return -EINVAL;
89 
90 	/* FIXME: what locks portdata fields ? */
91 	if (set & TIOCM_RTS)
92 		portdata->rts_state = 1;
93 	if (set & TIOCM_DTR)
94 		portdata->dtr_state = 1;
95 
96 	if (clear & TIOCM_RTS)
97 		portdata->rts_state = 0;
98 	if (clear & TIOCM_DTR)
99 		portdata->dtr_state = 0;
100 	return intfdata->send_setup(port);
101 }
102 EXPORT_SYMBOL(usb_wwan_tiocmset);
103 
104 static int get_serial_info(struct usb_serial_port *port,
105 			   struct serial_struct __user *retinfo)
106 {
107 	struct serial_struct tmp;
108 
109 	if (!retinfo)
110 		return -EFAULT;
111 
112 	memset(&tmp, 0, sizeof(tmp));
113 	tmp.line            = port->minor;
114 	tmp.port            = port->port_number;
115 	tmp.baud_base       = tty_get_baud_rate(port->port.tty);
116 	tmp.close_delay	    = port->port.close_delay / 10;
117 	tmp.closing_wait    = port->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
118 				 ASYNC_CLOSING_WAIT_NONE :
119 				 port->port.closing_wait / 10;
120 
121 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
122 		return -EFAULT;
123 	return 0;
124 }
125 
126 static int set_serial_info(struct usb_serial_port *port,
127 			   struct serial_struct __user *newinfo)
128 {
129 	struct serial_struct new_serial;
130 	unsigned int closing_wait, close_delay;
131 	int retval = 0;
132 
133 	if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
134 		return -EFAULT;
135 
136 	close_delay = new_serial.close_delay * 10;
137 	closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
138 			ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;
139 
140 	mutex_lock(&port->port.mutex);
141 
142 	if (!capable(CAP_SYS_ADMIN)) {
143 		if ((close_delay != port->port.close_delay) ||
144 		    (closing_wait != port->port.closing_wait))
145 			retval = -EPERM;
146 		else
147 			retval = -EOPNOTSUPP;
148 	} else {
149 		port->port.close_delay  = close_delay;
150 		port->port.closing_wait = closing_wait;
151 	}
152 
153 	mutex_unlock(&port->port.mutex);
154 	return retval;
155 }
156 
157 int usb_wwan_ioctl(struct tty_struct *tty,
158 		   unsigned int cmd, unsigned long arg)
159 {
160 	struct usb_serial_port *port = tty->driver_data;
161 
162 	dev_dbg(&port->dev, "%s cmd 0x%04x\n", __func__, cmd);
163 
164 	switch (cmd) {
165 	case TIOCGSERIAL:
166 		return get_serial_info(port,
167 				       (struct serial_struct __user *) arg);
168 	case TIOCSSERIAL:
169 		return set_serial_info(port,
170 				       (struct serial_struct __user *) arg);
171 	default:
172 		break;
173 	}
174 
175 	dev_dbg(&port->dev, "%s arg not supported\n", __func__);
176 
177 	return -ENOIOCTLCMD;
178 }
179 EXPORT_SYMBOL(usb_wwan_ioctl);
180 
181 int usb_wwan_write(struct tty_struct *tty, struct usb_serial_port *port,
182 		   const unsigned char *buf, int count)
183 {
184 	struct usb_wwan_port_private *portdata;
185 	struct usb_wwan_intf_private *intfdata;
186 	int i;
187 	int left, todo;
188 	struct urb *this_urb = NULL;	/* spurious */
189 	int err;
190 	unsigned long flags;
191 
192 	portdata = usb_get_serial_port_data(port);
193 	intfdata = usb_get_serial_data(port->serial);
194 
195 	dev_dbg(&port->dev, "%s: write (%d chars)\n", __func__, count);
196 
197 	i = 0;
198 	left = count;
199 	for (i = 0; left > 0 && i < N_OUT_URB; i++) {
200 		todo = left;
201 		if (todo > OUT_BUFLEN)
202 			todo = OUT_BUFLEN;
203 
204 		this_urb = portdata->out_urbs[i];
205 		if (test_and_set_bit(i, &portdata->out_busy)) {
206 			if (time_before(jiffies,
207 					portdata->tx_start_time[i] + 10 * HZ))
208 				continue;
209 			usb_unlink_urb(this_urb);
210 			continue;
211 		}
212 		dev_dbg(&port->dev, "%s: endpoint %d buf %d\n", __func__,
213 			usb_pipeendpoint(this_urb->pipe), i);
214 
215 		err = usb_autopm_get_interface_async(port->serial->interface);
216 		if (err < 0) {
217 			clear_bit(i, &portdata->out_busy);
218 			break;
219 		}
220 
221 		/* send the data */
222 		memcpy(this_urb->transfer_buffer, buf, todo);
223 		this_urb->transfer_buffer_length = todo;
224 
225 		spin_lock_irqsave(&intfdata->susp_lock, flags);
226 		if (intfdata->suspended) {
227 			usb_anchor_urb(this_urb, &portdata->delayed);
228 			spin_unlock_irqrestore(&intfdata->susp_lock, flags);
229 		} else {
230 			intfdata->in_flight++;
231 			spin_unlock_irqrestore(&intfdata->susp_lock, flags);
232 			err = usb_submit_urb(this_urb, GFP_ATOMIC);
233 			if (err) {
234 				dev_err(&port->dev,
235 					"%s: submit urb %d failed: %d\n",
236 					__func__, i, err);
237 				clear_bit(i, &portdata->out_busy);
238 				spin_lock_irqsave(&intfdata->susp_lock, flags);
239 				intfdata->in_flight--;
240 				spin_unlock_irqrestore(&intfdata->susp_lock,
241 						       flags);
242 				usb_autopm_put_interface_async(port->serial->interface);
243 				break;
244 			}
245 		}
246 
247 		portdata->tx_start_time[i] = jiffies;
248 		buf += todo;
249 		left -= todo;
250 	}
251 
252 	count -= left;
253 	dev_dbg(&port->dev, "%s: wrote (did %d)\n", __func__, count);
254 	return count;
255 }
256 EXPORT_SYMBOL(usb_wwan_write);
257 
258 static void usb_wwan_indat_callback(struct urb *urb)
259 {
260 	int err;
261 	int endpoint;
262 	struct usb_serial_port *port;
263 	struct device *dev;
264 	unsigned char *data = urb->transfer_buffer;
265 	int status = urb->status;
266 
267 	endpoint = usb_pipeendpoint(urb->pipe);
268 	port = urb->context;
269 	dev = &port->dev;
270 
271 	if (status) {
272 		dev_dbg(dev, "%s: nonzero status: %d on endpoint %02x.\n",
273 			__func__, status, endpoint);
274 	} else {
275 		if (urb->actual_length) {
276 			tty_insert_flip_string(&port->port, data,
277 					urb->actual_length);
278 			tty_flip_buffer_push(&port->port);
279 		} else
280 			dev_dbg(dev, "%s: empty read urb received\n", __func__);
281 	}
282 	/* Resubmit urb so we continue receiving */
283 	err = usb_submit_urb(urb, GFP_ATOMIC);
284 	if (err) {
285 		if (err != -EPERM) {
286 			dev_err(dev, "%s: resubmit read urb failed. (%d)\n",
287 				__func__, err);
288 			/* busy also in error unless we are killed */
289 			usb_mark_last_busy(port->serial->dev);
290 		}
291 	} else {
292 		usb_mark_last_busy(port->serial->dev);
293 	}
294 }
295 
296 static void usb_wwan_outdat_callback(struct urb *urb)
297 {
298 	struct usb_serial_port *port;
299 	struct usb_wwan_port_private *portdata;
300 	struct usb_wwan_intf_private *intfdata;
301 	int i;
302 
303 	port = urb->context;
304 	intfdata = usb_get_serial_data(port->serial);
305 
306 	usb_serial_port_softint(port);
307 	usb_autopm_put_interface_async(port->serial->interface);
308 	portdata = usb_get_serial_port_data(port);
309 	spin_lock(&intfdata->susp_lock);
310 	intfdata->in_flight--;
311 	spin_unlock(&intfdata->susp_lock);
312 
313 	for (i = 0; i < N_OUT_URB; ++i) {
314 		if (portdata->out_urbs[i] == urb) {
315 			smp_mb__before_atomic();
316 			clear_bit(i, &portdata->out_busy);
317 			break;
318 		}
319 	}
320 }
321 
322 int usb_wwan_write_room(struct tty_struct *tty)
323 {
324 	struct usb_serial_port *port = tty->driver_data;
325 	struct usb_wwan_port_private *portdata;
326 	int i;
327 	int data_len = 0;
328 	struct urb *this_urb;
329 
330 	portdata = usb_get_serial_port_data(port);
331 
332 	for (i = 0; i < N_OUT_URB; i++) {
333 		this_urb = portdata->out_urbs[i];
334 		if (this_urb && !test_bit(i, &portdata->out_busy))
335 			data_len += OUT_BUFLEN;
336 	}
337 
338 	dev_dbg(&port->dev, "%s: %d\n", __func__, data_len);
339 	return data_len;
340 }
341 EXPORT_SYMBOL(usb_wwan_write_room);
342 
343 int usb_wwan_chars_in_buffer(struct tty_struct *tty)
344 {
345 	struct usb_serial_port *port = tty->driver_data;
346 	struct usb_wwan_port_private *portdata;
347 	int i;
348 	int data_len = 0;
349 	struct urb *this_urb;
350 
351 	portdata = usb_get_serial_port_data(port);
352 
353 	for (i = 0; i < N_OUT_URB; i++) {
354 		this_urb = portdata->out_urbs[i];
355 		/* FIXME: This locking is insufficient as this_urb may
356 		   go unused during the test */
357 		if (this_urb && test_bit(i, &portdata->out_busy))
358 			data_len += this_urb->transfer_buffer_length;
359 	}
360 	dev_dbg(&port->dev, "%s: %d\n", __func__, data_len);
361 	return data_len;
362 }
363 EXPORT_SYMBOL(usb_wwan_chars_in_buffer);
364 
365 int usb_wwan_open(struct tty_struct *tty, struct usb_serial_port *port)
366 {
367 	struct usb_wwan_port_private *portdata;
368 	struct usb_wwan_intf_private *intfdata;
369 	struct usb_serial *serial = port->serial;
370 	int i, err;
371 	struct urb *urb;
372 
373 	portdata = usb_get_serial_port_data(port);
374 	intfdata = usb_get_serial_data(serial);
375 
376 	if (port->interrupt_in_urb) {
377 		err = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
378 		if (err) {
379 			dev_err(&port->dev, "%s: submit int urb failed: %d\n",
380 				__func__, err);
381 		}
382 	}
383 
384 	/* Start reading from the IN endpoint */
385 	for (i = 0; i < N_IN_URB; i++) {
386 		urb = portdata->in_urbs[i];
387 		if (!urb)
388 			continue;
389 		err = usb_submit_urb(urb, GFP_KERNEL);
390 		if (err) {
391 			dev_err(&port->dev,
392 				"%s: submit read urb %d failed: %d\n",
393 				__func__, i, err);
394 		}
395 	}
396 
397 	spin_lock_irq(&intfdata->susp_lock);
398 	if (++intfdata->open_ports == 1)
399 		serial->interface->needs_remote_wakeup = 1;
400 	spin_unlock_irq(&intfdata->susp_lock);
401 	/* this balances a get in the generic USB serial code */
402 	usb_autopm_put_interface(serial->interface);
403 
404 	return 0;
405 }
406 EXPORT_SYMBOL(usb_wwan_open);
407 
408 static void unbusy_queued_urb(struct urb *urb,
409 					struct usb_wwan_port_private *portdata)
410 {
411 	int i;
412 
413 	for (i = 0; i < N_OUT_URB; i++) {
414 		if (urb == portdata->out_urbs[i]) {
415 			clear_bit(i, &portdata->out_busy);
416 			break;
417 		}
418 	}
419 }
420 
421 void usb_wwan_close(struct usb_serial_port *port)
422 {
423 	int i;
424 	struct usb_serial *serial = port->serial;
425 	struct usb_wwan_port_private *portdata;
426 	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
427 	struct urb *urb;
428 
429 	portdata = usb_get_serial_port_data(port);
430 
431 	/*
432 	 * Need to take susp_lock to make sure port is not already being
433 	 * resumed, but no need to hold it due to ASYNC_INITIALIZED.
434 	 */
435 	spin_lock_irq(&intfdata->susp_lock);
436 	if (--intfdata->open_ports == 0)
437 		serial->interface->needs_remote_wakeup = 0;
438 	spin_unlock_irq(&intfdata->susp_lock);
439 
440 	for (;;) {
441 		urb = usb_get_from_anchor(&portdata->delayed);
442 		if (!urb)
443 			break;
444 		unbusy_queued_urb(urb, portdata);
445 		usb_autopm_put_interface_async(serial->interface);
446 	}
447 
448 	for (i = 0; i < N_IN_URB; i++)
449 		usb_kill_urb(portdata->in_urbs[i]);
450 	for (i = 0; i < N_OUT_URB; i++)
451 		usb_kill_urb(portdata->out_urbs[i]);
452 	usb_kill_urb(port->interrupt_in_urb);
453 
454 	usb_autopm_get_interface_no_resume(serial->interface);
455 }
456 EXPORT_SYMBOL(usb_wwan_close);
457 
458 static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
459 				      int endpoint,
460 				      int dir, void *ctx, char *buf, int len,
461 				      void (*callback) (struct urb *))
462 {
463 	struct usb_serial *serial = port->serial;
464 	struct urb *urb;
465 
466 	urb = usb_alloc_urb(0, GFP_KERNEL);	/* No ISO */
467 	if (!urb)
468 		return NULL;
469 
470 	usb_fill_bulk_urb(urb, serial->dev,
471 			  usb_sndbulkpipe(serial->dev, endpoint) | dir,
472 			  buf, len, callback, ctx);
473 
474 	return urb;
475 }
476 
477 int usb_wwan_port_probe(struct usb_serial_port *port)
478 {
479 	struct usb_wwan_port_private *portdata;
480 	struct urb *urb;
481 	u8 *buffer;
482 	int i;
483 
484 	if (!port->bulk_in_size || !port->bulk_out_size)
485 		return -ENODEV;
486 
487 	portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
488 	if (!portdata)
489 		return -ENOMEM;
490 
491 	init_usb_anchor(&portdata->delayed);
492 
493 	for (i = 0; i < N_IN_URB; i++) {
494 		buffer = (u8 *)__get_free_page(GFP_KERNEL);
495 		if (!buffer)
496 			goto bail_out_error;
497 		portdata->in_buffer[i] = buffer;
498 
499 		urb = usb_wwan_setup_urb(port, port->bulk_in_endpointAddress,
500 						USB_DIR_IN, port,
501 						buffer, IN_BUFLEN,
502 						usb_wwan_indat_callback);
503 		portdata->in_urbs[i] = urb;
504 	}
505 
506 	for (i = 0; i < N_OUT_URB; i++) {
507 		buffer = kmalloc(OUT_BUFLEN, GFP_KERNEL);
508 		if (!buffer)
509 			goto bail_out_error2;
510 		portdata->out_buffer[i] = buffer;
511 
512 		urb = usb_wwan_setup_urb(port, port->bulk_out_endpointAddress,
513 						USB_DIR_OUT, port,
514 						buffer, OUT_BUFLEN,
515 						usb_wwan_outdat_callback);
516 		portdata->out_urbs[i] = urb;
517 	}
518 
519 	usb_set_serial_port_data(port, portdata);
520 
521 	return 0;
522 
523 bail_out_error2:
524 	for (i = 0; i < N_OUT_URB; i++) {
525 		usb_free_urb(portdata->out_urbs[i]);
526 		kfree(portdata->out_buffer[i]);
527 	}
528 bail_out_error:
529 	for (i = 0; i < N_IN_URB; i++) {
530 		usb_free_urb(portdata->in_urbs[i]);
531 		free_page((unsigned long)portdata->in_buffer[i]);
532 	}
533 	kfree(portdata);
534 
535 	return -ENOMEM;
536 }
537 EXPORT_SYMBOL_GPL(usb_wwan_port_probe);
538 
539 int usb_wwan_port_remove(struct usb_serial_port *port)
540 {
541 	int i;
542 	struct usb_wwan_port_private *portdata;
543 
544 	portdata = usb_get_serial_port_data(port);
545 	usb_set_serial_port_data(port, NULL);
546 
547 	for (i = 0; i < N_IN_URB; i++) {
548 		usb_free_urb(portdata->in_urbs[i]);
549 		free_page((unsigned long)portdata->in_buffer[i]);
550 	}
551 	for (i = 0; i < N_OUT_URB; i++) {
552 		usb_free_urb(portdata->out_urbs[i]);
553 		kfree(portdata->out_buffer[i]);
554 	}
555 
556 	kfree(portdata);
557 
558 	return 0;
559 }
560 EXPORT_SYMBOL(usb_wwan_port_remove);
561 
562 #ifdef CONFIG_PM
563 static void stop_urbs(struct usb_serial *serial)
564 {
565 	int i, j;
566 	struct usb_serial_port *port;
567 	struct usb_wwan_port_private *portdata;
568 
569 	for (i = 0; i < serial->num_ports; ++i) {
570 		port = serial->port[i];
571 		portdata = usb_get_serial_port_data(port);
572 		if (!portdata)
573 			continue;
574 		for (j = 0; j < N_IN_URB; j++)
575 			usb_kill_urb(portdata->in_urbs[j]);
576 		for (j = 0; j < N_OUT_URB; j++)
577 			usb_kill_urb(portdata->out_urbs[j]);
578 		usb_kill_urb(port->interrupt_in_urb);
579 	}
580 }
581 
582 int usb_wwan_suspend(struct usb_serial *serial, pm_message_t message)
583 {
584 	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
585 
586 	spin_lock_irq(&intfdata->susp_lock);
587 	if (PMSG_IS_AUTO(message)) {
588 		if (intfdata->in_flight) {
589 			spin_unlock_irq(&intfdata->susp_lock);
590 			return -EBUSY;
591 		}
592 	}
593 	intfdata->suspended = 1;
594 	spin_unlock_irq(&intfdata->susp_lock);
595 
596 	stop_urbs(serial);
597 
598 	return 0;
599 }
600 EXPORT_SYMBOL(usb_wwan_suspend);
601 
602 /* Caller must hold susp_lock. */
603 static int usb_wwan_submit_delayed_urbs(struct usb_serial_port *port)
604 {
605 	struct usb_serial *serial = port->serial;
606 	struct usb_wwan_intf_private *data = usb_get_serial_data(serial);
607 	struct usb_wwan_port_private *portdata;
608 	struct urb *urb;
609 	int err_count = 0;
610 	int err;
611 
612 	portdata = usb_get_serial_port_data(port);
613 
614 	for (;;) {
615 		urb = usb_get_from_anchor(&portdata->delayed);
616 		if (!urb)
617 			break;
618 
619 		err = usb_submit_urb(urb, GFP_ATOMIC);
620 		if (err) {
621 			dev_err(&port->dev, "%s: submit urb failed: %d\n",
622 					__func__, err);
623 			err_count++;
624 			unbusy_queued_urb(urb, portdata);
625 			usb_autopm_put_interface_async(serial->interface);
626 			continue;
627 		}
628 		data->in_flight++;
629 	}
630 
631 	if (err_count)
632 		return -EIO;
633 
634 	return 0;
635 }
636 
637 int usb_wwan_resume(struct usb_serial *serial)
638 {
639 	int i, j;
640 	struct usb_serial_port *port;
641 	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
642 	struct usb_wwan_port_private *portdata;
643 	struct urb *urb;
644 	int err;
645 	int err_count = 0;
646 
647 	spin_lock_irq(&intfdata->susp_lock);
648 	for (i = 0; i < serial->num_ports; i++) {
649 		port = serial->port[i];
650 
651 		if (!test_bit(ASYNCB_INITIALIZED, &port->port.flags))
652 			continue;
653 
654 		portdata = usb_get_serial_port_data(port);
655 
656 		if (port->interrupt_in_urb) {
657 			err = usb_submit_urb(port->interrupt_in_urb,
658 					GFP_ATOMIC);
659 			if (err) {
660 				dev_err(&port->dev,
661 					"%s: submit int urb failed: %d\n",
662 					__func__, err);
663 				err_count++;
664 			}
665 		}
666 
667 		err = usb_wwan_submit_delayed_urbs(port);
668 		if (err)
669 			err_count++;
670 
671 		for (j = 0; j < N_IN_URB; j++) {
672 			urb = portdata->in_urbs[j];
673 			err = usb_submit_urb(urb, GFP_ATOMIC);
674 			if (err < 0) {
675 				dev_err(&port->dev,
676 					"%s: submit read urb %d failed: %d\n",
677 					__func__, i, err);
678 				err_count++;
679 			}
680 		}
681 	}
682 	intfdata->suspended = 0;
683 	spin_unlock_irq(&intfdata->susp_lock);
684 
685 	if (err_count)
686 		return -EIO;
687 
688 	return 0;
689 }
690 EXPORT_SYMBOL(usb_wwan_resume);
691 #endif
692 
693 MODULE_AUTHOR(DRIVER_AUTHOR);
694 MODULE_DESCRIPTION(DRIVER_DESC);
695 MODULE_LICENSE("GPL");
696