USB: usb_wwan: fix write and suspend race
[pandora-kernel.git] / drivers / usb / serial / usb_wwan.c
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 int debug;
41
42 void usb_wwan_dtr_rts(struct usb_serial_port *port, int on)
43 {
44         struct usb_wwan_port_private *portdata;
45
46         struct usb_wwan_intf_private *intfdata;
47
48         dbg("%s", __func__);
49
50         intfdata = port->serial->private;
51
52         if (!intfdata->send_setup)
53                 return;
54
55         portdata = usb_get_serial_port_data(port);
56         /* FIXME: locking */
57         portdata->rts_state = on;
58         portdata->dtr_state = on;
59
60         intfdata->send_setup(port);
61 }
62 EXPORT_SYMBOL(usb_wwan_dtr_rts);
63
64 void usb_wwan_set_termios(struct tty_struct *tty,
65                           struct usb_serial_port *port,
66                           struct ktermios *old_termios)
67 {
68         struct usb_wwan_intf_private *intfdata = port->serial->private;
69
70         dbg("%s", __func__);
71
72         /* Doesn't support option setting */
73         tty_termios_copy_hw(tty->termios, old_termios);
74
75         if (intfdata->send_setup)
76                 intfdata->send_setup(port);
77 }
78 EXPORT_SYMBOL(usb_wwan_set_termios);
79
80 int usb_wwan_tiocmget(struct tty_struct *tty)
81 {
82         struct usb_serial_port *port = tty->driver_data;
83         unsigned int value;
84         struct usb_wwan_port_private *portdata;
85
86         portdata = usb_get_serial_port_data(port);
87
88         value = ((portdata->rts_state) ? TIOCM_RTS : 0) |
89             ((portdata->dtr_state) ? TIOCM_DTR : 0) |
90             ((portdata->cts_state) ? TIOCM_CTS : 0) |
91             ((portdata->dsr_state) ? TIOCM_DSR : 0) |
92             ((portdata->dcd_state) ? TIOCM_CAR : 0) |
93             ((portdata->ri_state) ? TIOCM_RNG : 0);
94
95         return value;
96 }
97 EXPORT_SYMBOL(usb_wwan_tiocmget);
98
99 int usb_wwan_tiocmset(struct tty_struct *tty,
100                       unsigned int set, unsigned int clear)
101 {
102         struct usb_serial_port *port = tty->driver_data;
103         struct usb_wwan_port_private *portdata;
104         struct usb_wwan_intf_private *intfdata;
105
106         portdata = usb_get_serial_port_data(port);
107         intfdata = port->serial->private;
108
109         if (!intfdata->send_setup)
110                 return -EINVAL;
111
112         /* FIXME: what locks portdata fields ? */
113         if (set & TIOCM_RTS)
114                 portdata->rts_state = 1;
115         if (set & TIOCM_DTR)
116                 portdata->dtr_state = 1;
117
118         if (clear & TIOCM_RTS)
119                 portdata->rts_state = 0;
120         if (clear & TIOCM_DTR)
121                 portdata->dtr_state = 0;
122         return intfdata->send_setup(port);
123 }
124 EXPORT_SYMBOL(usb_wwan_tiocmset);
125
126 static int get_serial_info(struct usb_serial_port *port,
127                            struct serial_struct __user *retinfo)
128 {
129         struct serial_struct tmp;
130
131         if (!retinfo)
132                 return -EFAULT;
133
134         memset(&tmp, 0, sizeof(tmp));
135         tmp.line            = port->serial->minor;
136         tmp.port            = port->number;
137         tmp.baud_base       = tty_get_baud_rate(port->port.tty);
138         tmp.close_delay     = port->port.close_delay / 10;
139         tmp.closing_wait    = port->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
140                                  ASYNC_CLOSING_WAIT_NONE :
141                                  port->port.closing_wait / 10;
142
143         if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
144                 return -EFAULT;
145         return 0;
146 }
147
148 static int set_serial_info(struct usb_serial_port *port,
149                            struct serial_struct __user *newinfo)
150 {
151         struct serial_struct new_serial;
152         unsigned int closing_wait, close_delay;
153         int retval = 0;
154
155         if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
156                 return -EFAULT;
157
158         close_delay = new_serial.close_delay * 10;
159         closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
160                         ASYNC_CLOSING_WAIT_NONE : new_serial.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 }
178
179 int usb_wwan_ioctl(struct tty_struct *tty,
180                    unsigned int cmd, unsigned long arg)
181 {
182         struct usb_serial_port *port = tty->driver_data;
183
184         dbg("%s cmd 0x%04x", __func__, cmd);
185
186         switch (cmd) {
187         case TIOCGSERIAL:
188                 return get_serial_info(port,
189                                        (struct serial_struct __user *) arg);
190         case TIOCSSERIAL:
191                 return set_serial_info(port,
192                                        (struct serial_struct __user *) arg);
193         default:
194                 break;
195         }
196
197         dbg("%s arg not supported", __func__);
198
199         return -ENOIOCTLCMD;
200 }
201 EXPORT_SYMBOL(usb_wwan_ioctl);
202
203 /* Write */
204 int usb_wwan_write(struct tty_struct *tty, struct usb_serial_port *port,
205                    const unsigned char *buf, int count)
206 {
207         struct usb_wwan_port_private *portdata;
208         struct usb_wwan_intf_private *intfdata;
209         int i;
210         int left, todo;
211         struct urb *this_urb = NULL;    /* spurious */
212         int err;
213         unsigned long flags;
214
215         portdata = usb_get_serial_port_data(port);
216         intfdata = port->serial->private;
217
218         dbg("%s: write (%d chars)", __func__, count);
219
220         i = 0;
221         left = count;
222         for (i = 0; left > 0 && i < N_OUT_URB; i++) {
223                 todo = left;
224                 if (todo > OUT_BUFLEN)
225                         todo = OUT_BUFLEN;
226
227                 this_urb = portdata->out_urbs[i];
228                 if (test_and_set_bit(i, &portdata->out_busy)) {
229                         if (time_before(jiffies,
230                                         portdata->tx_start_time[i] + 10 * HZ))
231                                 continue;
232                         usb_unlink_urb(this_urb);
233                         continue;
234                 }
235                 dbg("%s: endpoint %d buf %d", __func__,
236                     usb_pipeendpoint(this_urb->pipe), i);
237
238                 err = usb_autopm_get_interface_async(port->serial->interface);
239                 if (err < 0) {
240                         clear_bit(i, &portdata->out_busy);
241                         break;
242                 }
243
244                 /* send the data */
245                 memcpy(this_urb->transfer_buffer, buf, todo);
246                 this_urb->transfer_buffer_length = todo;
247
248                 spin_lock_irqsave(&intfdata->susp_lock, flags);
249                 if (intfdata->suspended) {
250                         usb_anchor_urb(this_urb, &portdata->delayed);
251                         spin_unlock_irqrestore(&intfdata->susp_lock, flags);
252                 } else {
253                         intfdata->in_flight++;
254                         spin_unlock_irqrestore(&intfdata->susp_lock, flags);
255                         err = usb_submit_urb(this_urb, GFP_ATOMIC);
256                         if (err) {
257                                 dbg("usb_submit_urb %p (write bulk) failed "
258                                     "(%d)", this_urb, err);
259                                 clear_bit(i, &portdata->out_busy);
260                                 spin_lock_irqsave(&intfdata->susp_lock, flags);
261                                 intfdata->in_flight--;
262                                 spin_unlock_irqrestore(&intfdata->susp_lock,
263                                                        flags);
264                                 usb_autopm_put_interface_async(port->serial->interface);
265                                 break;
266                         }
267                 }
268
269                 portdata->tx_start_time[i] = jiffies;
270                 buf += todo;
271                 left -= todo;
272         }
273
274         count -= left;
275         dbg("%s: wrote (did %d)", __func__, count);
276         return count;
277 }
278 EXPORT_SYMBOL(usb_wwan_write);
279
280 static void usb_wwan_indat_callback(struct urb *urb)
281 {
282         int err;
283         int endpoint;
284         struct usb_serial_port *port;
285         struct tty_struct *tty;
286         unsigned char *data = urb->transfer_buffer;
287         int status = urb->status;
288
289         dbg("%s: %p", __func__, urb);
290
291         endpoint = usb_pipeendpoint(urb->pipe);
292         port = urb->context;
293
294         if (status) {
295                 dbg("%s: nonzero status: %d on endpoint %02x.",
296                     __func__, status, endpoint);
297         } else {
298                 tty = tty_port_tty_get(&port->port);
299                 if (tty) {
300                         if (urb->actual_length) {
301                                 tty_insert_flip_string(tty, data,
302                                                 urb->actual_length);
303                                 tty_flip_buffer_push(tty);
304                         } else
305                                 dbg("%s: empty read urb received", __func__);
306                         tty_kref_put(tty);
307                 }
308
309                 /* Resubmit urb so we continue receiving */
310                 if (status != -ESHUTDOWN) {
311                         err = usb_submit_urb(urb, GFP_ATOMIC);
312                         if (err) {
313                                 if (err != -EPERM) {
314                                         printk(KERN_ERR "%s: resubmit read urb failed. "
315                                                 "(%d)", __func__, err);
316                                         /* busy also in error unless we are killed */
317                                         usb_mark_last_busy(port->serial->dev);
318                                 }
319                         } else {
320                                 usb_mark_last_busy(port->serial->dev);
321                         }
322                 }
323
324         }
325 }
326
327 static void usb_wwan_outdat_callback(struct urb *urb)
328 {
329         struct usb_serial_port *port;
330         struct usb_wwan_port_private *portdata;
331         struct usb_wwan_intf_private *intfdata;
332         int i;
333
334         dbg("%s", __func__);
335
336         port = urb->context;
337         intfdata = port->serial->private;
338
339         usb_serial_port_softint(port);
340         usb_autopm_put_interface_async(port->serial->interface);
341         portdata = usb_get_serial_port_data(port);
342         spin_lock(&intfdata->susp_lock);
343         intfdata->in_flight--;
344         spin_unlock(&intfdata->susp_lock);
345
346         for (i = 0; i < N_OUT_URB; ++i) {
347                 if (portdata->out_urbs[i] == urb) {
348                         smp_mb__before_clear_bit();
349                         clear_bit(i, &portdata->out_busy);
350                         break;
351                 }
352         }
353 }
354
355 int usb_wwan_write_room(struct tty_struct *tty)
356 {
357         struct usb_serial_port *port = tty->driver_data;
358         struct usb_wwan_port_private *portdata;
359         int i;
360         int data_len = 0;
361         struct urb *this_urb;
362
363         portdata = usb_get_serial_port_data(port);
364
365         for (i = 0; i < N_OUT_URB; i++) {
366                 this_urb = portdata->out_urbs[i];
367                 if (this_urb && !test_bit(i, &portdata->out_busy))
368                         data_len += OUT_BUFLEN;
369         }
370
371         dbg("%s: %d", __func__, data_len);
372         return data_len;
373 }
374 EXPORT_SYMBOL(usb_wwan_write_room);
375
376 int usb_wwan_chars_in_buffer(struct tty_struct *tty)
377 {
378         struct usb_serial_port *port = tty->driver_data;
379         struct usb_wwan_port_private *portdata;
380         int i;
381         int data_len = 0;
382         struct urb *this_urb;
383
384         portdata = usb_get_serial_port_data(port);
385
386         for (i = 0; i < N_OUT_URB; i++) {
387                 this_urb = portdata->out_urbs[i];
388                 /* FIXME: This locking is insufficient as this_urb may
389                    go unused during the test */
390                 if (this_urb && test_bit(i, &portdata->out_busy))
391                         data_len += this_urb->transfer_buffer_length;
392         }
393         dbg("%s: %d", __func__, data_len);
394         return data_len;
395 }
396 EXPORT_SYMBOL(usb_wwan_chars_in_buffer);
397
398 int usb_wwan_open(struct tty_struct *tty, struct usb_serial_port *port)
399 {
400         struct usb_wwan_port_private *portdata;
401         struct usb_wwan_intf_private *intfdata;
402         struct usb_serial *serial = port->serial;
403         int i, err;
404         struct urb *urb;
405
406         portdata = usb_get_serial_port_data(port);
407         intfdata = serial->private;
408
409         dbg("%s", __func__);
410
411         /* Start reading from the IN endpoint */
412         for (i = 0; i < N_IN_URB; i++) {
413                 urb = portdata->in_urbs[i];
414                 if (!urb)
415                         continue;
416                 err = usb_submit_urb(urb, GFP_KERNEL);
417                 if (err) {
418                         dbg("%s: submit urb %d failed (%d) %d",
419                             __func__, i, err, urb->transfer_buffer_length);
420                 }
421         }
422
423         if (intfdata->send_setup)
424                 intfdata->send_setup(port);
425
426         serial->interface->needs_remote_wakeup = 1;
427         spin_lock_irq(&intfdata->susp_lock);
428         portdata->opened = 1;
429         spin_unlock_irq(&intfdata->susp_lock);
430         /* this balances a get in the generic USB serial code */
431         usb_autopm_put_interface(serial->interface);
432
433         return 0;
434 }
435 EXPORT_SYMBOL(usb_wwan_open);
436
437 void usb_wwan_close(struct usb_serial_port *port)
438 {
439         int i;
440         struct usb_serial *serial = port->serial;
441         struct usb_wwan_port_private *portdata;
442         struct usb_wwan_intf_private *intfdata = port->serial->private;
443
444         dbg("%s", __func__);
445         portdata = usb_get_serial_port_data(port);
446
447         if (serial->dev) {
448                 /* Stop reading/writing urbs */
449                 spin_lock_irq(&intfdata->susp_lock);
450                 portdata->opened = 0;
451                 spin_unlock_irq(&intfdata->susp_lock);
452
453                 for (i = 0; i < N_IN_URB; i++)
454                         usb_kill_urb(portdata->in_urbs[i]);
455                 for (i = 0; i < N_OUT_URB; i++)
456                         usb_kill_urb(portdata->out_urbs[i]);
457                 /* balancing - important as an error cannot be handled*/
458                 usb_autopm_get_interface_no_resume(serial->interface);
459                 serial->interface->needs_remote_wakeup = 0;
460         }
461 }
462 EXPORT_SYMBOL(usb_wwan_close);
463
464 /* Helper functions used by usb_wwan_setup_urbs */
465 static struct urb *usb_wwan_setup_urb(struct usb_serial *serial, int endpoint,
466                                       int dir, void *ctx, char *buf, int len,
467                                       void (*callback) (struct urb *))
468 {
469         struct urb *urb;
470
471         if (endpoint == -1)
472                 return NULL;    /* endpoint not needed */
473
474         urb = usb_alloc_urb(0, GFP_KERNEL);     /* No ISO */
475         if (urb == NULL) {
476                 dbg("%s: alloc for endpoint %d failed.", __func__, endpoint);
477                 return NULL;
478         }
479
480         /* Fill URB using supplied data. */
481         usb_fill_bulk_urb(urb, serial->dev,
482                           usb_sndbulkpipe(serial->dev, endpoint) | dir,
483                           buf, len, callback, ctx);
484
485         return urb;
486 }
487
488 /* Setup urbs */
489 static void usb_wwan_setup_urbs(struct usb_serial *serial)
490 {
491         int i, j;
492         struct usb_serial_port *port;
493         struct usb_wwan_port_private *portdata;
494
495         dbg("%s", __func__);
496
497         for (i = 0; i < serial->num_ports; i++) {
498                 port = serial->port[i];
499                 portdata = usb_get_serial_port_data(port);
500
501                 /* Do indat endpoints first */
502                 for (j = 0; j < N_IN_URB; ++j) {
503                         portdata->in_urbs[j] = usb_wwan_setup_urb(serial,
504                                                                   port->
505                                                                   bulk_in_endpointAddress,
506                                                                   USB_DIR_IN,
507                                                                   port,
508                                                                   portdata->
509                                                                   in_buffer[j],
510                                                                   IN_BUFLEN,
511                                                                   usb_wwan_indat_callback);
512                 }
513
514                 /* outdat endpoints */
515                 for (j = 0; j < N_OUT_URB; ++j) {
516                         portdata->out_urbs[j] = usb_wwan_setup_urb(serial,
517                                                                    port->
518                                                                    bulk_out_endpointAddress,
519                                                                    USB_DIR_OUT,
520                                                                    port,
521                                                                    portdata->
522                                                                    out_buffer
523                                                                    [j],
524                                                                    OUT_BUFLEN,
525                                                                    usb_wwan_outdat_callback);
526                 }
527         }
528 }
529
530 int usb_wwan_startup(struct usb_serial *serial)
531 {
532         int i, j, err;
533         struct usb_serial_port *port;
534         struct usb_wwan_port_private *portdata;
535         u8 *buffer;
536
537         dbg("%s", __func__);
538
539         /* Now setup per port private data */
540         for (i = 0; i < serial->num_ports; i++) {
541                 port = serial->port[i];
542                 portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
543                 if (!portdata) {
544                         dbg("%s: kmalloc for usb_wwan_port_private (%d) failed!.",
545                             __func__, i);
546                         return 1;
547                 }
548                 init_usb_anchor(&portdata->delayed);
549
550                 for (j = 0; j < N_IN_URB; j++) {
551                         buffer = (u8 *) __get_free_page(GFP_KERNEL);
552                         if (!buffer)
553                                 goto bail_out_error;
554                         portdata->in_buffer[j] = buffer;
555                 }
556
557                 for (j = 0; j < N_OUT_URB; j++) {
558                         buffer = kmalloc(OUT_BUFLEN, GFP_KERNEL);
559                         if (!buffer)
560                                 goto bail_out_error2;
561                         portdata->out_buffer[j] = buffer;
562                 }
563
564                 usb_set_serial_port_data(port, portdata);
565
566                 if (!port->interrupt_in_urb)
567                         continue;
568                 err = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
569                 if (err)
570                         dbg("%s: submit irq_in urb failed %d", __func__, err);
571         }
572         usb_wwan_setup_urbs(serial);
573         return 0;
574
575 bail_out_error2:
576         for (j = 0; j < N_OUT_URB; j++)
577                 kfree(portdata->out_buffer[j]);
578 bail_out_error:
579         for (j = 0; j < N_IN_URB; j++)
580                 if (portdata->in_buffer[j])
581                         free_page((unsigned long)portdata->in_buffer[j]);
582         kfree(portdata);
583         return 1;
584 }
585 EXPORT_SYMBOL(usb_wwan_startup);
586
587 static void stop_read_write_urbs(struct usb_serial *serial)
588 {
589         int i, j;
590         struct usb_serial_port *port;
591         struct usb_wwan_port_private *portdata;
592
593         /* Stop reading/writing urbs */
594         for (i = 0; i < serial->num_ports; ++i) {
595                 port = serial->port[i];
596                 portdata = usb_get_serial_port_data(port);
597                 for (j = 0; j < N_IN_URB; j++)
598                         usb_kill_urb(portdata->in_urbs[j]);
599                 for (j = 0; j < N_OUT_URB; j++)
600                         usb_kill_urb(portdata->out_urbs[j]);
601         }
602 }
603
604 void usb_wwan_disconnect(struct usb_serial *serial)
605 {
606         dbg("%s", __func__);
607
608         stop_read_write_urbs(serial);
609 }
610 EXPORT_SYMBOL(usb_wwan_disconnect);
611
612 void usb_wwan_release(struct usb_serial *serial)
613 {
614         int i, j;
615         struct usb_serial_port *port;
616         struct usb_wwan_port_private *portdata;
617
618         dbg("%s", __func__);
619
620         /* Now free them */
621         for (i = 0; i < serial->num_ports; ++i) {
622                 port = serial->port[i];
623                 portdata = usb_get_serial_port_data(port);
624
625                 for (j = 0; j < N_IN_URB; j++) {
626                         usb_free_urb(portdata->in_urbs[j]);
627                         free_page((unsigned long)
628                                   portdata->in_buffer[j]);
629                         portdata->in_urbs[j] = NULL;
630                 }
631                 for (j = 0; j < N_OUT_URB; j++) {
632                         usb_free_urb(portdata->out_urbs[j]);
633                         kfree(portdata->out_buffer[j]);
634                         portdata->out_urbs[j] = NULL;
635                 }
636         }
637
638         /* Now free per port private data */
639         for (i = 0; i < serial->num_ports; i++) {
640                 port = serial->port[i];
641                 kfree(usb_get_serial_port_data(port));
642         }
643 }
644 EXPORT_SYMBOL(usb_wwan_release);
645
646 #ifdef CONFIG_PM
647 int usb_wwan_suspend(struct usb_serial *serial, pm_message_t message)
648 {
649         struct usb_wwan_intf_private *intfdata = serial->private;
650
651         dbg("%s entered", __func__);
652
653         spin_lock_irq(&intfdata->susp_lock);
654         if (PMSG_IS_AUTO(message)) {
655                 if (intfdata->in_flight) {
656                         spin_unlock_irq(&intfdata->susp_lock);
657                         return -EBUSY;
658                 }
659         }
660         intfdata->suspended = 1;
661         spin_unlock_irq(&intfdata->susp_lock);
662
663         stop_read_write_urbs(serial);
664
665         return 0;
666 }
667 EXPORT_SYMBOL(usb_wwan_suspend);
668
669 static void unbusy_queued_urb(struct urb *urb, struct usb_wwan_port_private *portdata)
670 {
671         int i;
672
673         for (i = 0; i < N_OUT_URB; i++) {
674                 if (urb == portdata->out_urbs[i]) {
675                         clear_bit(i, &portdata->out_busy);
676                         break;
677                 }
678         }
679 }
680
681 static void play_delayed(struct usb_serial_port *port)
682 {
683         struct usb_wwan_intf_private *data;
684         struct usb_wwan_port_private *portdata;
685         struct urb *urb;
686         int err;
687
688         portdata = usb_get_serial_port_data(port);
689         data = port->serial->private;
690         while ((urb = usb_get_from_anchor(&portdata->delayed))) {
691                 err = usb_submit_urb(urb, GFP_ATOMIC);
692                 if (!err) {
693                         data->in_flight++;
694                 } else {
695                         /* we have to throw away the rest */
696                         do {
697                                 unbusy_queued_urb(urb, portdata);
698                                 usb_autopm_put_interface_no_suspend(port->serial->interface);
699                         } while ((urb = usb_get_from_anchor(&portdata->delayed)));
700                         break;
701                 }
702         }
703 }
704
705 int usb_wwan_resume(struct usb_serial *serial)
706 {
707         int i, j;
708         struct usb_serial_port *port;
709         struct usb_wwan_intf_private *intfdata = serial->private;
710         struct usb_wwan_port_private *portdata;
711         struct urb *urb;
712         int err = 0;
713
714         dbg("%s entered", __func__);
715         /* get the interrupt URBs resubmitted unconditionally */
716         for (i = 0; i < serial->num_ports; i++) {
717                 port = serial->port[i];
718                 if (!port->interrupt_in_urb) {
719                         dbg("%s: No interrupt URB for port %d", __func__, i);
720                         continue;
721                 }
722                 err = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
723                 dbg("Submitted interrupt URB for port %d (result %d)", i, err);
724                 if (err < 0) {
725                         err("%s: Error %d for interrupt URB of port%d",
726                             __func__, err, i);
727                         goto err_out;
728                 }
729         }
730
731         spin_lock_irq(&intfdata->susp_lock);
732         for (i = 0; i < serial->num_ports; i++) {
733                 /* walk all ports */
734                 port = serial->port[i];
735                 portdata = usb_get_serial_port_data(port);
736
737                 /* skip closed ports */
738                 if (!portdata->opened)
739                         continue;
740
741                 for (j = 0; j < N_IN_URB; j++) {
742                         urb = portdata->in_urbs[j];
743                         err = usb_submit_urb(urb, GFP_ATOMIC);
744                         if (err < 0) {
745                                 err("%s: Error %d for bulk URB %d",
746                                     __func__, err, i);
747                                 spin_unlock_irq(&intfdata->susp_lock);
748                                 goto err_out;
749                         }
750                 }
751                 play_delayed(port);
752         }
753         intfdata->suspended = 0;
754         spin_unlock_irq(&intfdata->susp_lock);
755 err_out:
756         return err;
757 }
758 EXPORT_SYMBOL(usb_wwan_resume);
759 #endif
760
761 MODULE_AUTHOR(DRIVER_AUTHOR);
762 MODULE_DESCRIPTION(DRIVER_DESC);
763 MODULE_VERSION(DRIVER_VERSION);
764 MODULE_LICENSE("GPL");
765
766 module_param(debug, bool, S_IRUGO | S_IWUSR);
767 MODULE_PARM_DESC(debug, "Debug messages");