xref: /linux/drivers/usb/serial/usb_wwan.c (revision 95e9fd10f06cb5642028b6b851e32b8c8afb4571)
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_VERSION "v0.7.2"
23 #define DRIVER_AUTHOR "Matthias Urlichs <smurf@smurf.noris.de>"
24 #define DRIVER_DESC "USB Driver for GSM modems"
25 
26 #include <linux/kernel.h>
27 #include <linux/jiffies.h>
28 #include <linux/errno.h>
29 #include <linux/slab.h>
30 #include <linux/tty.h>
31 #include <linux/tty_flip.h>
32 #include <linux/module.h>
33 #include <linux/bitops.h>
34 #include <linux/uaccess.h>
35 #include <linux/usb.h>
36 #include <linux/usb/serial.h>
37 #include <linux/serial.h>
38 #include "usb-wwan.h"
39 
40 static bool debug;
41 
42 void usb_wwan_dtr_rts(struct usb_serial_port *port, int on)
43 {
44 	struct usb_serial *serial = port->serial;
45 	struct usb_wwan_port_private *portdata;
46 	struct usb_wwan_intf_private *intfdata;
47 
48 	intfdata = port->serial->private;
49 
50 	if (!intfdata->send_setup)
51 		return;
52 
53 	portdata = usb_get_serial_port_data(port);
54 	mutex_lock(&serial->disc_mutex);
55 	portdata->rts_state = on;
56 	portdata->dtr_state = on;
57 	if (serial->dev)
58 		intfdata->send_setup(port);
59 	mutex_unlock(&serial->disc_mutex);
60 }
61 EXPORT_SYMBOL(usb_wwan_dtr_rts);
62 
63 void usb_wwan_set_termios(struct tty_struct *tty,
64 			  struct usb_serial_port *port,
65 			  struct ktermios *old_termios)
66 {
67 	struct usb_wwan_intf_private *intfdata = port->serial->private;
68 
69 	/* Doesn't support option setting */
70 	tty_termios_copy_hw(tty->termios, old_termios);
71 
72 	if (intfdata->send_setup)
73 		intfdata->send_setup(port);
74 }
75 EXPORT_SYMBOL(usb_wwan_set_termios);
76 
77 int usb_wwan_tiocmget(struct tty_struct *tty)
78 {
79 	struct usb_serial_port *port = tty->driver_data;
80 	unsigned int value;
81 	struct usb_wwan_port_private *portdata;
82 
83 	portdata = usb_get_serial_port_data(port);
84 
85 	value = ((portdata->rts_state) ? TIOCM_RTS : 0) |
86 	    ((portdata->dtr_state) ? TIOCM_DTR : 0) |
87 	    ((portdata->cts_state) ? TIOCM_CTS : 0) |
88 	    ((portdata->dsr_state) ? TIOCM_DSR : 0) |
89 	    ((portdata->dcd_state) ? TIOCM_CAR : 0) |
90 	    ((portdata->ri_state) ? TIOCM_RNG : 0);
91 
92 	return value;
93 }
94 EXPORT_SYMBOL(usb_wwan_tiocmget);
95 
96 int usb_wwan_tiocmset(struct tty_struct *tty,
97 		      unsigned int set, unsigned int clear)
98 {
99 	struct usb_serial_port *port = tty->driver_data;
100 	struct usb_wwan_port_private *portdata;
101 	struct usb_wwan_intf_private *intfdata;
102 
103 	portdata = usb_get_serial_port_data(port);
104 	intfdata = port->serial->private;
105 
106 	if (!intfdata->send_setup)
107 		return -EINVAL;
108 
109 	/* FIXME: what locks portdata fields ? */
110 	if (set & TIOCM_RTS)
111 		portdata->rts_state = 1;
112 	if (set & TIOCM_DTR)
113 		portdata->dtr_state = 1;
114 
115 	if (clear & TIOCM_RTS)
116 		portdata->rts_state = 0;
117 	if (clear & TIOCM_DTR)
118 		portdata->dtr_state = 0;
119 	return intfdata->send_setup(port);
120 }
121 EXPORT_SYMBOL(usb_wwan_tiocmset);
122 
123 static int get_serial_info(struct usb_serial_port *port,
124 			   struct serial_struct __user *retinfo)
125 {
126 	struct serial_struct tmp;
127 
128 	if (!retinfo)
129 		return -EFAULT;
130 
131 	memset(&tmp, 0, sizeof(tmp));
132 	tmp.line            = port->serial->minor;
133 	tmp.port            = port->number;
134 	tmp.baud_base       = tty_get_baud_rate(port->port.tty);
135 	tmp.close_delay	    = port->port.close_delay / 10;
136 	tmp.closing_wait    = port->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
137 				 ASYNC_CLOSING_WAIT_NONE :
138 				 port->port.closing_wait / 10;
139 
140 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
141 		return -EFAULT;
142 	return 0;
143 }
144 
145 static int set_serial_info(struct usb_serial_port *port,
146 			   struct serial_struct __user *newinfo)
147 {
148 	struct serial_struct new_serial;
149 	unsigned int closing_wait, close_delay;
150 	int retval = 0;
151 
152 	if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
153 		return -EFAULT;
154 
155 	close_delay = new_serial.close_delay * 10;
156 	closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
157 			ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;
158 
159 	mutex_lock(&port->port.mutex);
160 
161 	if (!capable(CAP_SYS_ADMIN)) {
162 		if ((close_delay != port->port.close_delay) ||
163 		    (closing_wait != port->port.closing_wait))
164 			retval = -EPERM;
165 		else
166 			retval = -EOPNOTSUPP;
167 	} else {
168 		port->port.close_delay  = close_delay;
169 		port->port.closing_wait = closing_wait;
170 	}
171 
172 	mutex_unlock(&port->port.mutex);
173 	return retval;
174 }
175 
176 int usb_wwan_ioctl(struct tty_struct *tty,
177 		   unsigned int cmd, unsigned long arg)
178 {
179 	struct usb_serial_port *port = tty->driver_data;
180 
181 	dbg("%s cmd 0x%04x", __func__, cmd);
182 
183 	switch (cmd) {
184 	case TIOCGSERIAL:
185 		return get_serial_info(port,
186 				       (struct serial_struct __user *) arg);
187 	case TIOCSSERIAL:
188 		return set_serial_info(port,
189 				       (struct serial_struct __user *) arg);
190 	default:
191 		break;
192 	}
193 
194 	dbg("%s arg not supported", __func__);
195 
196 	return -ENOIOCTLCMD;
197 }
198 EXPORT_SYMBOL(usb_wwan_ioctl);
199 
200 /* Write */
201 int usb_wwan_write(struct tty_struct *tty, struct usb_serial_port *port,
202 		   const unsigned char *buf, int count)
203 {
204 	struct usb_wwan_port_private *portdata;
205 	struct usb_wwan_intf_private *intfdata;
206 	int i;
207 	int left, todo;
208 	struct urb *this_urb = NULL;	/* spurious */
209 	int err;
210 	unsigned long flags;
211 
212 	portdata = usb_get_serial_port_data(port);
213 	intfdata = port->serial->private;
214 
215 	dbg("%s: write (%d chars)", __func__, count);
216 
217 	i = 0;
218 	left = count;
219 	for (i = 0; left > 0 && i < N_OUT_URB; i++) {
220 		todo = left;
221 		if (todo > OUT_BUFLEN)
222 			todo = OUT_BUFLEN;
223 
224 		this_urb = portdata->out_urbs[i];
225 		if (test_and_set_bit(i, &portdata->out_busy)) {
226 			if (time_before(jiffies,
227 					portdata->tx_start_time[i] + 10 * HZ))
228 				continue;
229 			usb_unlink_urb(this_urb);
230 			continue;
231 		}
232 		dbg("%s: endpoint %d buf %d", __func__,
233 		    usb_pipeendpoint(this_urb->pipe), i);
234 
235 		err = usb_autopm_get_interface_async(port->serial->interface);
236 		if (err < 0)
237 			break;
238 
239 		/* send the data */
240 		memcpy(this_urb->transfer_buffer, buf, todo);
241 		this_urb->transfer_buffer_length = todo;
242 
243 		spin_lock_irqsave(&intfdata->susp_lock, flags);
244 		if (intfdata->suspended) {
245 			usb_anchor_urb(this_urb, &portdata->delayed);
246 			spin_unlock_irqrestore(&intfdata->susp_lock, flags);
247 		} else {
248 			intfdata->in_flight++;
249 			spin_unlock_irqrestore(&intfdata->susp_lock, flags);
250 			err = usb_submit_urb(this_urb, GFP_ATOMIC);
251 			if (err) {
252 				dbg("usb_submit_urb %p (write bulk) failed "
253 				    "(%d)", this_urb, err);
254 				clear_bit(i, &portdata->out_busy);
255 				spin_lock_irqsave(&intfdata->susp_lock, flags);
256 				intfdata->in_flight--;
257 				spin_unlock_irqrestore(&intfdata->susp_lock,
258 						       flags);
259 				usb_autopm_put_interface_async(port->serial->interface);
260 				break;
261 			}
262 		}
263 
264 		portdata->tx_start_time[i] = jiffies;
265 		buf += todo;
266 		left -= todo;
267 	}
268 
269 	count -= left;
270 	dbg("%s: wrote (did %d)", __func__, count);
271 	return count;
272 }
273 EXPORT_SYMBOL(usb_wwan_write);
274 
275 static void usb_wwan_indat_callback(struct urb *urb)
276 {
277 	int err;
278 	int endpoint;
279 	struct usb_serial_port *port;
280 	struct tty_struct *tty;
281 	unsigned char *data = urb->transfer_buffer;
282 	int status = urb->status;
283 
284 	endpoint = usb_pipeendpoint(urb->pipe);
285 	port = urb->context;
286 
287 	if (status) {
288 		dbg("%s: nonzero status: %d on endpoint %02x.",
289 		    __func__, status, endpoint);
290 	} else {
291 		tty = tty_port_tty_get(&port->port);
292 		if (tty) {
293 			if (urb->actual_length) {
294 				tty_insert_flip_string(tty, data,
295 						urb->actual_length);
296 				tty_flip_buffer_push(tty);
297 			} else
298 				dbg("%s: empty read urb received", __func__);
299 			tty_kref_put(tty);
300 		}
301 
302 		/* Resubmit urb so we continue receiving */
303 		err = usb_submit_urb(urb, GFP_ATOMIC);
304 		if (err) {
305 			if (err != -EPERM) {
306 				printk(KERN_ERR "%s: resubmit read urb failed. "
307 					"(%d)", __func__, err);
308 				/* busy also in error unless we are killed */
309 				usb_mark_last_busy(port->serial->dev);
310 			}
311 		} else {
312 			usb_mark_last_busy(port->serial->dev);
313 		}
314 	}
315 }
316 
317 static void usb_wwan_outdat_callback(struct urb *urb)
318 {
319 	struct usb_serial_port *port;
320 	struct usb_wwan_port_private *portdata;
321 	struct usb_wwan_intf_private *intfdata;
322 	int i;
323 
324 	port = urb->context;
325 	intfdata = port->serial->private;
326 
327 	usb_serial_port_softint(port);
328 	usb_autopm_put_interface_async(port->serial->interface);
329 	portdata = usb_get_serial_port_data(port);
330 	spin_lock(&intfdata->susp_lock);
331 	intfdata->in_flight--;
332 	spin_unlock(&intfdata->susp_lock);
333 
334 	for (i = 0; i < N_OUT_URB; ++i) {
335 		if (portdata->out_urbs[i] == urb) {
336 			smp_mb__before_clear_bit();
337 			clear_bit(i, &portdata->out_busy);
338 			break;
339 		}
340 	}
341 }
342 
343 int usb_wwan_write_room(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 		if (this_urb && !test_bit(i, &portdata->out_busy))
356 			data_len += OUT_BUFLEN;
357 	}
358 
359 	dbg("%s: %d", __func__, data_len);
360 	return data_len;
361 }
362 EXPORT_SYMBOL(usb_wwan_write_room);
363 
364 int usb_wwan_chars_in_buffer(struct tty_struct *tty)
365 {
366 	struct usb_serial_port *port = tty->driver_data;
367 	struct usb_wwan_port_private *portdata;
368 	int i;
369 	int data_len = 0;
370 	struct urb *this_urb;
371 
372 	portdata = usb_get_serial_port_data(port);
373 
374 	for (i = 0; i < N_OUT_URB; i++) {
375 		this_urb = portdata->out_urbs[i];
376 		/* FIXME: This locking is insufficient as this_urb may
377 		   go unused during the test */
378 		if (this_urb && test_bit(i, &portdata->out_busy))
379 			data_len += this_urb->transfer_buffer_length;
380 	}
381 	dbg("%s: %d", __func__, data_len);
382 	return data_len;
383 }
384 EXPORT_SYMBOL(usb_wwan_chars_in_buffer);
385 
386 int usb_wwan_open(struct tty_struct *tty, struct usb_serial_port *port)
387 {
388 	struct usb_wwan_port_private *portdata;
389 	struct usb_wwan_intf_private *intfdata;
390 	struct usb_serial *serial = port->serial;
391 	int i, err;
392 	struct urb *urb;
393 
394 	portdata = usb_get_serial_port_data(port);
395 	intfdata = serial->private;
396 
397 	/* Start reading from the IN endpoint */
398 	for (i = 0; i < N_IN_URB; i++) {
399 		urb = portdata->in_urbs[i];
400 		if (!urb)
401 			continue;
402 		err = usb_submit_urb(urb, GFP_KERNEL);
403 		if (err) {
404 			dbg("%s: submit urb %d failed (%d) %d",
405 			    __func__, i, err, urb->transfer_buffer_length);
406 		}
407 	}
408 
409 	if (intfdata->send_setup)
410 		intfdata->send_setup(port);
411 
412 	serial->interface->needs_remote_wakeup = 1;
413 	spin_lock_irq(&intfdata->susp_lock);
414 	portdata->opened = 1;
415 	spin_unlock_irq(&intfdata->susp_lock);
416 	/* this balances a get in the generic USB serial code */
417 	usb_autopm_put_interface(serial->interface);
418 
419 	return 0;
420 }
421 EXPORT_SYMBOL(usb_wwan_open);
422 
423 void usb_wwan_close(struct usb_serial_port *port)
424 {
425 	int i;
426 	struct usb_serial *serial = port->serial;
427 	struct usb_wwan_port_private *portdata;
428 	struct usb_wwan_intf_private *intfdata = port->serial->private;
429 
430 	portdata = usb_get_serial_port_data(port);
431 
432 	if (serial->dev) {
433 		/* Stop reading/writing urbs */
434 		spin_lock_irq(&intfdata->susp_lock);
435 		portdata->opened = 0;
436 		spin_unlock_irq(&intfdata->susp_lock);
437 
438 		for (i = 0; i < N_IN_URB; i++)
439 			usb_kill_urb(portdata->in_urbs[i]);
440 		for (i = 0; i < N_OUT_URB; i++)
441 			usb_kill_urb(portdata->out_urbs[i]);
442 		/* balancing - important as an error cannot be handled*/
443 		usb_autopm_get_interface_no_resume(serial->interface);
444 		serial->interface->needs_remote_wakeup = 0;
445 	}
446 }
447 EXPORT_SYMBOL(usb_wwan_close);
448 
449 /* Helper functions used by usb_wwan_setup_urbs */
450 static struct urb *usb_wwan_setup_urb(struct usb_serial *serial, int endpoint,
451 				      int dir, void *ctx, char *buf, int len,
452 				      void (*callback) (struct urb *))
453 {
454 	struct urb *urb;
455 
456 	if (endpoint == -1)
457 		return NULL;	/* endpoint not needed */
458 
459 	urb = usb_alloc_urb(0, GFP_KERNEL);	/* No ISO */
460 	if (urb == NULL) {
461 		dbg("%s: alloc for endpoint %d failed.", __func__, endpoint);
462 		return NULL;
463 	}
464 
465 	/* Fill URB using supplied data. */
466 	usb_fill_bulk_urb(urb, serial->dev,
467 			  usb_sndbulkpipe(serial->dev, endpoint) | dir,
468 			  buf, len, callback, ctx);
469 
470 	return urb;
471 }
472 
473 /* Setup urbs */
474 static void usb_wwan_setup_urbs(struct usb_serial *serial)
475 {
476 	int i, j;
477 	struct usb_serial_port *port;
478 	struct usb_wwan_port_private *portdata;
479 
480 	for (i = 0; i < serial->num_ports; i++) {
481 		port = serial->port[i];
482 		portdata = usb_get_serial_port_data(port);
483 
484 		/* Do indat endpoints first */
485 		for (j = 0; j < N_IN_URB; ++j) {
486 			portdata->in_urbs[j] = usb_wwan_setup_urb(serial,
487 								  port->
488 								  bulk_in_endpointAddress,
489 								  USB_DIR_IN,
490 								  port,
491 								  portdata->
492 								  in_buffer[j],
493 								  IN_BUFLEN,
494 								  usb_wwan_indat_callback);
495 		}
496 
497 		/* outdat endpoints */
498 		for (j = 0; j < N_OUT_URB; ++j) {
499 			portdata->out_urbs[j] = usb_wwan_setup_urb(serial,
500 								   port->
501 								   bulk_out_endpointAddress,
502 								   USB_DIR_OUT,
503 								   port,
504 								   portdata->
505 								   out_buffer
506 								   [j],
507 								   OUT_BUFLEN,
508 								   usb_wwan_outdat_callback);
509 		}
510 	}
511 }
512 
513 int usb_wwan_startup(struct usb_serial *serial)
514 {
515 	int i, j, err;
516 	struct usb_serial_port *port;
517 	struct usb_wwan_port_private *portdata;
518 	u8 *buffer;
519 
520 	/* Now setup per port private data */
521 	for (i = 0; i < serial->num_ports; i++) {
522 		port = serial->port[i];
523 		portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
524 		if (!portdata) {
525 			dbg("%s: kmalloc for usb_wwan_port_private (%d) failed!.",
526 			    __func__, i);
527 			return 1;
528 		}
529 		init_usb_anchor(&portdata->delayed);
530 
531 		for (j = 0; j < N_IN_URB; j++) {
532 			buffer = (u8 *) __get_free_page(GFP_KERNEL);
533 			if (!buffer)
534 				goto bail_out_error;
535 			portdata->in_buffer[j] = buffer;
536 		}
537 
538 		for (j = 0; j < N_OUT_URB; j++) {
539 			buffer = kmalloc(OUT_BUFLEN, GFP_KERNEL);
540 			if (!buffer)
541 				goto bail_out_error2;
542 			portdata->out_buffer[j] = buffer;
543 		}
544 
545 		usb_set_serial_port_data(port, portdata);
546 
547 		if (!port->interrupt_in_urb)
548 			continue;
549 		err = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
550 		if (err)
551 			dbg("%s: submit irq_in urb failed %d", __func__, err);
552 	}
553 	usb_wwan_setup_urbs(serial);
554 	return 0;
555 
556 bail_out_error2:
557 	for (j = 0; j < N_OUT_URB; j++)
558 		kfree(portdata->out_buffer[j]);
559 bail_out_error:
560 	for (j = 0; j < N_IN_URB; j++)
561 		if (portdata->in_buffer[j])
562 			free_page((unsigned long)portdata->in_buffer[j]);
563 	kfree(portdata);
564 	return 1;
565 }
566 EXPORT_SYMBOL(usb_wwan_startup);
567 
568 int usb_wwan_port_remove(struct usb_serial_port *port)
569 {
570 	int i;
571 	struct usb_wwan_port_private *portdata;
572 
573 	portdata = usb_get_serial_port_data(port);
574 	usb_set_serial_port_data(port, NULL);
575 
576 	/* Stop reading/writing urbs and free them */
577 	for (i = 0; i < N_IN_URB; i++) {
578 		usb_kill_urb(portdata->in_urbs[i]);
579 		usb_free_urb(portdata->in_urbs[i]);
580 		free_page((unsigned long)portdata->in_buffer[i]);
581 	}
582 	for (i = 0; i < N_OUT_URB; i++) {
583 		usb_kill_urb(portdata->out_urbs[i]);
584 		usb_free_urb(portdata->out_urbs[i]);
585 		kfree(portdata->out_buffer[i]);
586 	}
587 
588 	/* Now free port private data */
589 	kfree(portdata);
590 	return 0;
591 }
592 EXPORT_SYMBOL(usb_wwan_port_remove);
593 
594 #ifdef CONFIG_PM
595 static void stop_read_write_urbs(struct usb_serial *serial)
596 {
597 	int i, j;
598 	struct usb_serial_port *port;
599 	struct usb_wwan_port_private *portdata;
600 
601 	/* Stop reading/writing urbs */
602 	for (i = 0; i < serial->num_ports; ++i) {
603 		port = serial->port[i];
604 		portdata = usb_get_serial_port_data(port);
605 		if (!portdata)
606 			continue;
607 		for (j = 0; j < N_IN_URB; j++)
608 			usb_kill_urb(portdata->in_urbs[j]);
609 		for (j = 0; j < N_OUT_URB; j++)
610 			usb_kill_urb(portdata->out_urbs[j]);
611 	}
612 }
613 
614 int usb_wwan_suspend(struct usb_serial *serial, pm_message_t message)
615 {
616 	struct usb_wwan_intf_private *intfdata = serial->private;
617 	int b;
618 
619 	if (PMSG_IS_AUTO(message)) {
620 		spin_lock_irq(&intfdata->susp_lock);
621 		b = intfdata->in_flight;
622 		spin_unlock_irq(&intfdata->susp_lock);
623 
624 		if (b)
625 			return -EBUSY;
626 	}
627 
628 	spin_lock_irq(&intfdata->susp_lock);
629 	intfdata->suspended = 1;
630 	spin_unlock_irq(&intfdata->susp_lock);
631 	stop_read_write_urbs(serial);
632 
633 	return 0;
634 }
635 EXPORT_SYMBOL(usb_wwan_suspend);
636 
637 static void unbusy_queued_urb(struct urb *urb, struct usb_wwan_port_private *portdata)
638 {
639 	int i;
640 
641 	for (i = 0; i < N_OUT_URB; i++) {
642 		if (urb == portdata->out_urbs[i]) {
643 			clear_bit(i, &portdata->out_busy);
644 			break;
645 		}
646 	}
647 }
648 
649 static void play_delayed(struct usb_serial_port *port)
650 {
651 	struct usb_wwan_intf_private *data;
652 	struct usb_wwan_port_private *portdata;
653 	struct urb *urb;
654 	int err;
655 
656 	portdata = usb_get_serial_port_data(port);
657 	data = port->serial->private;
658 	while ((urb = usb_get_from_anchor(&portdata->delayed))) {
659 		err = usb_submit_urb(urb, GFP_ATOMIC);
660 		if (!err) {
661 			data->in_flight++;
662 		} else {
663 			/* we have to throw away the rest */
664 			do {
665 				unbusy_queued_urb(urb, portdata);
666 				usb_autopm_put_interface_no_suspend(port->serial->interface);
667 			} while ((urb = usb_get_from_anchor(&portdata->delayed)));
668 			break;
669 		}
670 	}
671 }
672 
673 int usb_wwan_resume(struct usb_serial *serial)
674 {
675 	int i, j;
676 	struct usb_serial_port *port;
677 	struct usb_wwan_intf_private *intfdata = serial->private;
678 	struct usb_wwan_port_private *portdata;
679 	struct urb *urb;
680 	int err = 0;
681 
682 	/* get the interrupt URBs resubmitted unconditionally */
683 	for (i = 0; i < serial->num_ports; i++) {
684 		port = serial->port[i];
685 		if (!port->interrupt_in_urb) {
686 			dbg("%s: No interrupt URB for port %d", __func__, i);
687 			continue;
688 		}
689 		err = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
690 		dbg("Submitted interrupt URB for port %d (result %d)", i, err);
691 		if (err < 0) {
692 			dev_err(&port->dev, "%s: Error %d for interrupt URB\n",
693 				__func__, err);
694 			goto err_out;
695 		}
696 	}
697 
698 	for (i = 0; i < serial->num_ports; i++) {
699 		/* walk all ports */
700 		port = serial->port[i];
701 		portdata = usb_get_serial_port_data(port);
702 
703 		/* skip closed ports */
704 		spin_lock_irq(&intfdata->susp_lock);
705 		if (!portdata || !portdata->opened) {
706 			spin_unlock_irq(&intfdata->susp_lock);
707 			continue;
708 		}
709 
710 		for (j = 0; j < N_IN_URB; j++) {
711 			urb = portdata->in_urbs[j];
712 			err = usb_submit_urb(urb, GFP_ATOMIC);
713 			if (err < 0) {
714 				dev_err(&port->dev, "%s: Error %d for bulk URB %d\n",
715 					__func__, err, i);
716 				spin_unlock_irq(&intfdata->susp_lock);
717 				goto err_out;
718 			}
719 		}
720 		play_delayed(port);
721 		spin_unlock_irq(&intfdata->susp_lock);
722 	}
723 	spin_lock_irq(&intfdata->susp_lock);
724 	intfdata->suspended = 0;
725 	spin_unlock_irq(&intfdata->susp_lock);
726 err_out:
727 	return err;
728 }
729 EXPORT_SYMBOL(usb_wwan_resume);
730 #endif
731 
732 MODULE_AUTHOR(DRIVER_AUTHOR);
733 MODULE_DESCRIPTION(DRIVER_DESC);
734 MODULE_VERSION(DRIVER_VERSION);
735 MODULE_LICENSE("GPL");
736 
737 module_param(debug, bool, S_IRUGO | S_IWUSR);
738 MODULE_PARM_DESC(debug, "Debug messages");
739