aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/usb/serial/usb_wwan.c
blob: fbc94679780168b9ef0a455dc0c1bcf0211d741e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
/*
  USB Driver layer for GSM modems

  Copyright (C) 2005  Matthias Urlichs <smurf@smurf.noris.de>

  This driver is free software; you can redistribute it and/or modify
  it under the terms of Version 2 of the GNU General Public License as
  published by the Free Software Foundation.

  Portions copied from the Keyspan driver by Hugh Blemings <hugh@blemings.org>

  History: see the git log.

  Work sponsored by: Sigos GmbH, Germany <info@sigos.de>

  This driver exists because the "normal" serial driver doesn't work too well
  with GSM modems. Issues:
  - data loss -- one single Receive URB is not nearly enough
  - controlling the baud rate doesn't make sense
*/

#define DRIVER_VERSION "v0.7.2"
#define DRIVER_AUTHOR "Matthias Urlichs <smurf@smurf.noris.de>"
#define DRIVER_DESC "USB Driver for GSM modems"

#include <linux/kernel.h>
#include <linux/jiffies.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/bitops.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include "usb-wwan.h"

static int debug;

void usb_wwan_dtr_rts(struct usb_serial_port *port, int on)
{
	struct usb_serial *serial = port->serial;
	struct usb_wwan_port_private *portdata;

	struct usb_wwan_intf_private *intfdata;

	dbg("%s", __func__);

	intfdata = port->serial->private;

	if (!intfdata->send_setup)
		return;

	portdata = usb_get_serial_port_data(port);
	mutex_lock(&serial->disc_mutex);
	portdata->rts_state = on;
	portdata->dtr_state = on;
	if (serial->dev)
		intfdata->send_setup(port);
	mutex_unlock(&serial->disc_mutex);
}
EXPORT_SYMBOL(usb_wwan_dtr_rts);

void usb_wwan_set_termios(struct tty_struct *tty,
			  struct usb_serial_port *port,
			  struct ktermios *old_termios)
{
	struct usb_wwan_intf_private *intfdata = port->serial->private;

	dbg("%s", __func__);

	/* Doesn't support option setting */
	tty_termios_copy_hw(tty->termios, old_termios);

	if (intfdata->send_setup)
		intfdata->send_setup(port);
}
EXPORT_SYMBOL(usb_wwan_set_termios);

int usb_wwan_tiocmget(struct tty_struct *tty, struct file *file)
{
	struct usb_serial_port *port = tty->driver_data;
	unsigned int value;
	struct usb_wwan_port_private *portdata;

	portdata = usb_get_serial_port_data(port);

	value = ((portdata->rts_state) ? TIOCM_RTS : 0) |
	    ((portdata->dtr_state) ? TIOCM_DTR : 0) |
	    ((portdata->cts_state) ? TIOCM_CTS : 0) |
	    ((portdata->dsr_state) ? TIOCM_DSR : 0) |
	    ((portdata->dcd_state) ? TIOCM_CAR : 0) |
	    ((portdata->ri_state) ? TIOCM_RNG : 0);

	return value;
}
EXPORT_SYMBOL(usb_wwan_tiocmget);

int usb_wwan_tiocmset(struct tty_struct *tty, struct file *file,
		      unsigned int set, unsigned int clear)
{
	struct usb_serial_port *port = tty->driver_data;
	struct usb_wwan_port_private *portdata;
	struct usb_wwan_intf_private *intfdata;

	portdata = usb_get_serial_port_data(port);
	intfdata = port->serial->private;

	if (!intfdata->send_setup)
		return -EINVAL;

	/* FIXME: what locks portdata fields ? */
	if (set & TIOCM_RTS)
		portdata->rts_state = 1;
	if (set & TIOCM_DTR)
		portdata->dtr_state = 1;

	if (clear & TIOCM_RTS)
		portdata->rts_state = 0;
	if (clear & TIOCM_DTR)
		portdata->dtr_state = 0;
	return intfdata->send_setup(port);
}
EXPORT_SYMBOL(usb_wwan_tiocmset);

/* Write */
int usb_wwan_write(struct tty_struct *tty, struct usb_serial_port *port,
		   const unsigned char *buf, int count)
{
	struct usb_wwan_port_private *portdata;
	struct usb_wwan_intf_private *intfdata;
	int i;
	int left, todo;
	struct urb *this_urb = NULL;	/* spurious */
	int err;
	unsigned long flags;

	portdata = usb_get_serial_port_data(port);
	intfdata = port->serial->private;

	dbg("%s: write (%d chars)", __func__, count);

	i = 0;
	left = count;
	for (i = 0; left > 0 && i < N_OUT_URB; i++) {
		todo = left;
		if (todo > OUT_BUFLEN)
			todo = OUT_BUFLEN;

		this_urb = portdata->out_urbs[i];
		if (test_and_set_bit(i, &portdata->out_busy)) {
			if (time_before(jiffies,
					portdata->tx_start_time[i] + 10 * HZ))
				continue;
			usb_unlink_urb(this_urb);
			continue;
		}
		dbg("%s: endpoint %d buf %d", __func__,
		    usb_pipeendpoint(this_urb->pipe), i);

		err = usb_autopm_get_interface_async(port->serial->interface);
		if (err < 0)
			break;

		/* send the data */
		memcpy(this_urb->transfer_buffer, buf, todo);
		this_urb->transfer_buffer_length = todo;

		spin_lock_irqsave(&intfdata->susp_lock, flags);
		if (intfdata->suspended) {
			usb_anchor_urb(this_urb, &portdata->delayed);
			spin_unlock_irqrestore(&intfdata->susp_lock, flags);
		} else {
			intfdata->in_flight++;
			spin_unlock_irqrestore(&intfdata->susp_lock, flags);
			err = usb_submit_urb(this_urb, GFP_ATOMIC);
			if (err) {
				dbg("usb_submit_urb %p (write bulk) failed "
				    "(%d)", this_urb, err);
				clear_bit(i, &portdata->out_busy);
				spin_lock_irqsave(&intfdata->susp_lock, flags);
				intfdata->in_flight--;
				spin_unlock_irqrestore(&intfdata->susp_lock,
						       flags);
				continue;
			}
		}

		portdata->tx_start_time[i] = jiffies;
		buf += todo;
		left -= todo;
	}

	count -= left;
	dbg("%s: wrote (did %d)", __func__, count);
	return count;
}
EXPORT_SYMBOL(usb_wwan_write);

static void usb_wwan_indat_callback(struct urb *urb)
{
	int err;
	int endpoint;
	struct usb_serial_port *port;
	struct tty_struct *tty;
	unsigned char *data = urb->transfer_buffer;
	int status = urb->status;

	dbg("%s: %p", __func__, urb);

	endpoint = usb_pipeendpoint(urb->pipe);
	port = urb->context;

	if (status) {
		dbg("%s: nonzero status: %d on endpoint %02x.",
		    __func__, status, endpoint);
	} else {
		tty = tty_port_tty_get(&port->port);
		if (urb->actual_length) {
			tty_insert_flip_string(tty, data, urb->actual_length);
			tty_flip_buffer_push(tty);
		} else
			dbg("%s: empty read urb received", __func__);
		tty_kref_put(tty);

		/* Resubmit urb so we continue receiving */
		if (status != -ESHUTDOWN) {
			err = usb_submit_urb(urb, GFP_ATOMIC);
			if (err && err != -EPERM)
				printk(KERN_ERR "%s: resubmit read urb failed. "
				       "(%d)", __func__, err);
			else
				usb_mark_last_busy(port->serial->dev);
		}

	}
}

static void usb_wwan_outdat_callback(struct urb *urb)
{
	struct usb_serial_port *port;
	struct usb_wwan_port_private *portdata;
	struct usb_wwan_intf_private *intfdata;
	int i;

	dbg("%s", __func__);

	port = urb->context;
	intfdata = port->serial->private;

	usb_serial_port_softint(port);
	usb_autopm_put_interface_async(port->serial->interface);
	portdata = usb_get_serial_port_data(port);
	spin_lock(&intfdata->susp_lock);
	intfdata->in_flight--;
	spin_unlock(&intfdata->susp_lock);

	for (i = 0; i < N_OUT_URB; ++i) {
		if (portdata->out_urbs[i] == urb) {
			smp_mb__before_clear_bit();
			clear_bit(i, &portdata->out_busy);
			break;
		}
	}
}

int usb_wwan_write_room(struct tty_struct *tty)
{
	struct usb_serial_port *port = tty->driver_data;
	struct usb_wwan_port_private *portdata;
	int i;
	int data_len = 0;
	struct urb *this_urb;

	portdata = usb_get_serial_port_data(port);

	for (i = 0; i < N_OUT_URB; i++) {
		this_urb = portdata->out_urbs[i];
		if (this_urb && !test_bit(i, &portdata->out_busy))
			data_len += OUT_BUFLEN;
	}

	dbg("%s: %d", __func__, data_len);
	return data_len;
}
EXPORT_SYMBOL(usb_wwan_write_room);

int usb_wwan_chars_in_buffer(struct tty_struct *tty)
{
	struct usb_serial_port *port = tty->driver_data;
	struct usb_wwan_port_private *portdata;
	int i;
	int data_len = 0;
	struct urb *this_urb;

	portdata = usb_get_serial_port_data(port);

	for (i = 0; i < N_OUT_URB; i++) {
		this_urb = portdata->out_urbs[i];
		/* FIXME: This locking is insufficient as this_urb may
		   go unused during the test */
		if (this_urb && test_bit(i, &portdata->out_busy))
			data_len += this_urb->transfer_buffer_length;
	}
	dbg("%s: %d", __func__, data_len);
	return data_len;
}
EXPORT_SYMBOL(usb_wwan_chars_in_buffer);

int usb_wwan_open(struct tty_struct *tty, struct usb_serial_port *port)
{
	struct usb_wwan_port_private *portdata;
	struct usb_wwan_intf_private *intfdata;
	struct usb_serial *serial = port->serial;
	int i, err;
	struct urb *urb;

	portdata = usb_get_serial_port_data(port);
	intfdata = serial->private;

	dbg("%s", __func__);

	/* Start reading from the IN endpoint */
	for (i = 0; i < N_IN_URB; i++) {
		urb = portdata->in_urbs[i];
		if (!urb)
			continue;
		err = usb_submit_urb(urb, GFP_KERNEL);
		if (err) {
			dbg("%s: submit urb %d failed (%d) %d",
			    __func__, i, err, urb->transfer_buffer_length);
		}
	}

	if (intfdata->send_setup)
		intfdata->send_setup(port);

	serial->interface->needs_remote_wakeup = 1;
	spin_lock_irq(&intfdata->susp_lock);
	portdata->opened = 1;
	spin_unlock_irq(&intfdata->susp_lock);
	usb_autopm_put_interface(serial->interface);

	return 0;
}
EXPORT_SYMBOL(usb_wwan_open);

void usb_wwan_close(struct usb_serial_port *port)
{
	int i;
	struct usb_serial *serial = port->serial;
	struct usb_wwan_port_private *portdata;
	struct usb_wwan_intf_private *intfdata = port->serial->private;

	dbg("%s", __func__);
	portdata = usb_get_serial_port_data(port);

	if (serial->dev) {
		/* Stop reading/writing urbs */
		spin_lock_irq(&intfdata->susp_lock);
		portdata->opened = 0;
		spin_unlock_irq(&intfdata->susp_lock);

		for (i = 0; i < N_IN_URB; i++)
			usb_kill_urb(portdata->in_urbs[i]);
		for (i = 0; i < N_OUT_URB; i++)
			usb_kill_urb(portdata->out_urbs[i]);
		usb_autopm_get_interface(serial->interface);
		serial->interface->needs_remote_wakeup = 0;
	}
}
EXPORT_SYMBOL(usb_wwan_close);

/* Helper functions used by usb_wwan_setup_urbs */
static struct urb *usb_wwan_setup_urb(struct usb_serial *serial, int endpoint,
				      int dir, void *ctx, char *buf, int len,
				      void (*callback) (struct urb *))
{
	struct urb *urb;

	if (endpoint == -1)
		return NULL;	/* endpoint not needed */

	urb = usb_alloc_urb(0, GFP_KERNEL);	/* No ISO */
	if (urb == NULL) {
		dbg("%s: alloc for endpoint %d failed.", __func__, endpoint);
		return NULL;
	}

	/* Fill URB using supplied data. */
	usb_fill_bulk_urb(urb, serial->dev,
			  usb_sndbulkpipe(serial->dev, endpoint) | dir,
			  buf, len, callback, ctx);

	return urb;
}

/* Setup urbs */
static void usb_wwan_setup_urbs(struct usb_serial *serial)
{
	int i, j;
	struct usb_serial_port *port;
	struct usb_wwan_port_private *portdata;

	dbg("%s", __func__);

	for (i = 0; i < serial->num_ports; i++) {
		port = serial->port[i];
		portdata = usb_get_serial_port_data(port);

		/* Do indat endpoints first */
		for (j = 0; j < N_IN_URB; ++j) {
			portdata->in_urbs[j] = usb_wwan_setup_urb(serial,
								  port->
								  bulk_in_endpointAddress,
								  USB_DIR_IN,
								  port,
								  portdata->
								  in_buffer[j],
								  IN_BUFLEN,
								  usb_wwan_indat_callback);
		}

		/* outdat endpoints */
		for (j = 0; j < N_OUT_URB; ++j) {
			portdata->out_urbs[j] = usb_wwan_setup_urb(serial,
								   port->
								   bulk_out_endpointAddress,
								   USB_DIR_OUT,
								   port,
								   portdata->
								   out_buffer
								   [j],
								   OUT_BUFLEN,
								   usb_wwan_outdat_callback);
		}
	}
}

int usb_wwan_startup(struct usb_serial *serial)
{
	int i, j, err;
	struct usb_serial_port *port;
	struct usb_wwan_port_private *portdata;
	u8 *buffer;

	dbg("%s", __func__);

	/* Now setup per port private data */
	for (i = 0; i < serial->num_ports; i++) {
		port = serial->port[i];
		portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
		if (!portdata) {
			dbg("%s: kmalloc for usb_wwan_port_private (%d) failed!.",
			    __func__, i);
			return 1;
		}
		init_usb_anchor(&portdata->delayed);

		for (j = 0; j < N_IN_URB; j++) {
			buffer = (u8 *) __get_free_page(GFP_KERNEL);
			if (!buffer)
				goto bail_out_error;
			portdata->in_buffer[j] = buffer;
		}

		for (j = 0; j < N_OUT_URB; j++) {
			buffer = kmalloc(OUT_BUFLEN, GFP_KERNEL);
			if (!buffer)
				goto bail_out_error2;
			portdata->out_buffer[j] = buffer;
		}

		usb_set_serial_port_data(port, portdata);

		if (!port->interrupt_in_urb)
			continue;
		err = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
		if (err)
			dbg("%s: submit irq_in urb failed %d", __func__, err);
	}
	usb_wwan_setup_urbs(serial);
	return 0;

bail_out_error2:
	for (j = 0; j < N_OUT_URB; j++)
		kfree(portdata->out_buffer[j]);
bail_out_error:
	for (j = 0; j < N_IN_URB; j++)
		if (portdata->in_buffer[j])
			free_page((unsigned long)portdata->in_buffer[j]);
	kfree(portdata);
	return 1;
}
EXPORT_SYMBOL(usb_wwan_startup);

static void stop_read_write_urbs(struct usb_serial *serial)
{
	int i, j;
	struct usb_serial_port *port;
	struct usb_wwan_port_private *portdata;

	/* Stop reading/writing urbs */
	for (i = 0; i < serial->num_ports; ++i) {
		port = serial->port[i];
		portdata = usb_get_serial_port_data(port);
		for (j = 0; j < N_IN_URB; j++)
			usb_kill_urb(portdata->in_urbs[j]);
		for (j = 0; j < N_OUT_URB; j++)
			usb_kill_urb(portdata->out_urbs[j]);
	}
}

void usb_wwan_disconnect(struct usb_serial *serial)
{
	dbg("%s", __func__);

	stop_read_write_urbs(serial);
}
EXPORT_SYMBOL(usb_wwan_disconnect);

void usb_wwan_release(struct usb_serial *serial)
{
	int i, j;
	struct usb_serial_port *port;
	struct usb_wwan_port_private *portdata;

	dbg("%s", __func__);

	/* Now free them */
	for (i = 0; i < serial->num_ports; ++i) {
		port = serial->port[i];
		portdata = usb_get_serial_port_data(port);

		for (j = 0; j < N_IN_URB; j++) {
			usb_free_urb(portdata->in_urbs[j]);
			free_page((unsigned long)
				  portdata->in_buffer[j]);
			portdata->in_urbs[j] = NULL;
		}
		for (j = 0; j < N_OUT_URB; j++) {
			usb_free_urb(portdata->out_urbs[j]);
			kfree(portdata->out_buffer[j]);
			portdata->out_urbs[j] = NULL;
		}
	}

	/* Now free per port private data */
	for (i = 0; i < serial->num_ports; i++) {
		port = serial->port[i];
		kfree(usb_get_serial_port_data(port));
	}
}
EXPORT_SYMBOL(usb_wwan_release);

#ifdef CONFIG_PM
int usb_wwan_suspend(struct usb_serial *serial, pm_message_t message)
{
	struct usb_wwan_intf_private *intfdata = serial->private;
	int b;

	dbg("%s entered", __func__);

	if (message.event & PM_EVENT_AUTO) {
		spin_lock_irq(&intfdata->susp_lock);
		b = intfdata->in_flight;
		spin_unlock_irq(&intfdata->susp_lock);

		if (b)
			return -EBUSY;
	}

	spin_lock_irq(&intfdata->susp_lock);
	intfdata->suspended = 1;
	spin_unlock_irq(&intfdata->susp_lock);
	stop_read_write_urbs(serial);

	return 0;
}
EXPORT_SYMBOL(usb_wwan_suspend);

static void play_delayed(struct usb_serial_port *port)
{
	struct usb_wwan_intf_private *data;
	struct usb_wwan_port_private *portdata;
	struct urb *urb;
	int err;

	portdata = usb_get_serial_port_data(port);
	data = port->serial->private;
	while ((urb = usb_get_from_anchor(&portdata->delayed))) {
		err = usb_submit_urb(urb, GFP_ATOMIC);
		if (!err)
			data->in_flight++;
	}
}

int usb_wwan_resume(struct usb_serial *serial)
{
	int i, j;
	struct usb_serial_port *port;
	struct usb_wwan_intf_private *intfdata = serial->private;
	struct usb_wwan_port_private *portdata;
	struct urb *urb;
	int err = 0;

	dbg("%s entered", __func__);
	/* get the interrupt URBs resubmitted unconditionally */
	for (i = 0; i < serial->num_ports; i++) {
		port = serial->port[i];
		if (!port->interrupt_in_urb) {
			dbg("%s: No interrupt URB for port %d", __func__, i);
			continue;
		}
		err = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
		dbg("Submitted interrupt URB for port %d (result %d)", i, err);
		if (err < 0) {
			err("%s: Error %d for interrupt URB of port%d",
			    __func__, err, i);
			goto err_out;
		}
	}

	for (i = 0; i < serial->num_ports; i++) {
		/* walk all ports */
		port = serial->port[i];
		portdata = usb_get_serial_port_data(port);

		/* skip closed ports */
		spin_lock_irq(&intfdata->susp_lock);
		if (!portdata->opened) {
			spin_unlock_irq(&intfdata->susp_lock);
			continue;
		}

		for (j = 0; j < N_IN_URB; j++) {
			urb = portdata->in_urbs[j];
			err = usb_submit_urb(urb, GFP_ATOMIC);
			if (err < 0) {
				err("%s: Error %d for bulk URB %d",
				    __func__, err, i);
				spin_unlock_irq(&intfdata->susp_lock);
				goto err_out;
			}
		}
		play_delayed(port);
		spin_unlock_irq(&intfdata->susp_lock);
	}
	spin_lock_irq(&intfdata->susp_lock);
	intfdata->suspended = 0;
	spin_unlock_irq(&intfdata->susp_lock);
err_out:
	return err;
}
EXPORT_SYMBOL(usb_wwan_resume);
#endif

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_VERSION(DRIVER_VERSION);
MODULE_LICENSE("GPL");

module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug messages");