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v5.4
  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	} else {
274		if (urb->actual_length) {
275			tty_insert_flip_string(&port->port, data,
276					urb->actual_length);
277			tty_flip_buffer_push(&port->port);
278		} else
279			dev_dbg(dev, "%s: empty read urb received\n", __func__);
280	}
281	/* Resubmit urb so we continue receiving */
282	err = usb_submit_urb(urb, GFP_ATOMIC);
283	if (err) {
284		if (err != -EPERM && err != -ENODEV) {
285			dev_err(dev, "%s: resubmit read urb failed. (%d)\n",
286				__func__, err);
287			/* busy also in error unless we are killed */
288			usb_mark_last_busy(port->serial->dev);
289		}
290	} else {
291		usb_mark_last_busy(port->serial->dev);
292	}
293}
294
295static void usb_wwan_outdat_callback(struct urb *urb)
296{
297	struct usb_serial_port *port;
298	struct usb_wwan_port_private *portdata;
299	struct usb_wwan_intf_private *intfdata;
300	unsigned long flags;
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_irqsave(&intfdata->susp_lock, flags);
310	intfdata->in_flight--;
311	spin_unlock_irqrestore(&intfdata->susp_lock, flags);
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
322int 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}
341EXPORT_SYMBOL(usb_wwan_write_room);
342
343int 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}
363EXPORT_SYMBOL(usb_wwan_chars_in_buffer);
364
365int 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}
406EXPORT_SYMBOL(usb_wwan_open);
407
408static 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
421void 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 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}
456EXPORT_SYMBOL(usb_wwan_close);
457
458static 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
477int 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
523bail_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	}
528bail_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}
537EXPORT_SYMBOL_GPL(usb_wwan_port_probe);
538
539int 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}
560EXPORT_SYMBOL(usb_wwan_port_remove);
561
562#ifdef CONFIG_PM
563static 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
582int 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}
600EXPORT_SYMBOL(usb_wwan_suspend);
601
602/* Caller must hold susp_lock. */
603static 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
637int 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 (!tty_port_initialized(&port->port))
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}
690EXPORT_SYMBOL(usb_wwan_resume);
691#endif
692
693MODULE_AUTHOR(DRIVER_AUTHOR);
694MODULE_DESCRIPTION(DRIVER_DESC);
695MODULE_LICENSE("GPL v2");
v4.10.11
 
  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/*
 40 * Generate DTR/RTS signals on the port using the SET_CONTROL_LINE_STATE request
 41 * in CDC ACM.
 42 */
 43static int usb_wwan_send_setup(struct usb_serial_port *port)
 44{
 45	struct usb_serial *serial = port->serial;
 46	struct usb_wwan_port_private *portdata;
 47	int val = 0;
 48	int ifnum;
 49	int res;
 50
 51	portdata = usb_get_serial_port_data(port);
 52
 53	if (portdata->dtr_state)
 54		val |= 0x01;
 55	if (portdata->rts_state)
 56		val |= 0x02;
 57
 58	ifnum = serial->interface->cur_altsetting->desc.bInterfaceNumber;
 59
 60	res = usb_autopm_get_interface(serial->interface);
 61	if (res)
 62		return res;
 63
 64	res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 65				0x22, 0x21, val, ifnum, NULL, 0,
 66				USB_CTRL_SET_TIMEOUT);
 67
 68	usb_autopm_put_interface(port->serial->interface);
 69
 70	return res;
 71}
 72
 73void usb_wwan_dtr_rts(struct usb_serial_port *port, int on)
 74{
 75	struct usb_wwan_port_private *portdata;
 76	struct usb_wwan_intf_private *intfdata;
 77
 78	intfdata = usb_get_serial_data(port->serial);
 79
 80	if (!intfdata->use_send_setup)
 81		return;
 82
 83	portdata = usb_get_serial_port_data(port);
 84	/* FIXME: locking */
 85	portdata->rts_state = on;
 86	portdata->dtr_state = on;
 87
 88	usb_wwan_send_setup(port);
 89}
 90EXPORT_SYMBOL(usb_wwan_dtr_rts);
 91
 92int usb_wwan_tiocmget(struct tty_struct *tty)
 93{
 94	struct usb_serial_port *port = tty->driver_data;
 95	unsigned int value;
 96	struct usb_wwan_port_private *portdata;
 97
 98	portdata = usb_get_serial_port_data(port);
 99
100	value = ((portdata->rts_state) ? TIOCM_RTS : 0) |
101	    ((portdata->dtr_state) ? TIOCM_DTR : 0) |
102	    ((portdata->cts_state) ? TIOCM_CTS : 0) |
103	    ((portdata->dsr_state) ? TIOCM_DSR : 0) |
104	    ((portdata->dcd_state) ? TIOCM_CAR : 0) |
105	    ((portdata->ri_state) ? TIOCM_RNG : 0);
106
107	return value;
108}
109EXPORT_SYMBOL(usb_wwan_tiocmget);
110
111int usb_wwan_tiocmset(struct tty_struct *tty,
112		      unsigned int set, unsigned int clear)
113{
114	struct usb_serial_port *port = tty->driver_data;
115	struct usb_wwan_port_private *portdata;
116	struct usb_wwan_intf_private *intfdata;
117
118	portdata = usb_get_serial_port_data(port);
119	intfdata = usb_get_serial_data(port->serial);
120
121	if (!intfdata->use_send_setup)
122		return -EINVAL;
123
124	/* FIXME: what locks portdata fields ? */
125	if (set & TIOCM_RTS)
126		portdata->rts_state = 1;
127	if (set & TIOCM_DTR)
128		portdata->dtr_state = 1;
129
130	if (clear & TIOCM_RTS)
131		portdata->rts_state = 0;
132	if (clear & TIOCM_DTR)
133		portdata->dtr_state = 0;
134	return usb_wwan_send_setup(port);
135}
136EXPORT_SYMBOL(usb_wwan_tiocmset);
137
138static int get_serial_info(struct usb_serial_port *port,
139			   struct serial_struct __user *retinfo)
140{
141	struct serial_struct tmp;
142
143	memset(&tmp, 0, sizeof(tmp));
144	tmp.line            = port->minor;
145	tmp.port            = port->port_number;
146	tmp.baud_base       = tty_get_baud_rate(port->port.tty);
147	tmp.close_delay	    = port->port.close_delay / 10;
148	tmp.closing_wait    = port->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
149				 ASYNC_CLOSING_WAIT_NONE :
150				 port->port.closing_wait / 10;
151
152	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
153		return -EFAULT;
154	return 0;
155}
 
156
157static int set_serial_info(struct usb_serial_port *port,
158			   struct serial_struct __user *newinfo)
159{
160	struct serial_struct new_serial;
161	unsigned int closing_wait, close_delay;
162	int retval = 0;
163
164	if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
165		return -EFAULT;
166
167	close_delay = new_serial.close_delay * 10;
168	closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
169			ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;
170
171	mutex_lock(&port->port.mutex);
172
173	if (!capable(CAP_SYS_ADMIN)) {
174		if ((close_delay != port->port.close_delay) ||
175		    (closing_wait != port->port.closing_wait))
176			retval = -EPERM;
177		else
178			retval = -EOPNOTSUPP;
179	} else {
180		port->port.close_delay  = close_delay;
181		port->port.closing_wait = closing_wait;
182	}
183
184	mutex_unlock(&port->port.mutex);
185	return retval;
186}
187
188int usb_wwan_ioctl(struct tty_struct *tty,
189		   unsigned int cmd, unsigned long arg)
190{
191	struct usb_serial_port *port = tty->driver_data;
192
193	dev_dbg(&port->dev, "%s cmd 0x%04x\n", __func__, cmd);
194
195	switch (cmd) {
196	case TIOCGSERIAL:
197		return get_serial_info(port,
198				       (struct serial_struct __user *) arg);
199	case TIOCSSERIAL:
200		return set_serial_info(port,
201				       (struct serial_struct __user *) arg);
202	default:
203		break;
204	}
205
206	dev_dbg(&port->dev, "%s arg not supported\n", __func__);
207
208	return -ENOIOCTLCMD;
209}
210EXPORT_SYMBOL(usb_wwan_ioctl);
211
212int usb_wwan_write(struct tty_struct *tty, struct usb_serial_port *port,
213		   const unsigned char *buf, int count)
214{
215	struct usb_wwan_port_private *portdata;
216	struct usb_wwan_intf_private *intfdata;
217	int i;
218	int left, todo;
219	struct urb *this_urb = NULL;	/* spurious */
220	int err;
221	unsigned long flags;
222
223	portdata = usb_get_serial_port_data(port);
224	intfdata = usb_get_serial_data(port->serial);
225
226	dev_dbg(&port->dev, "%s: write (%d chars)\n", __func__, count);
227
228	i = 0;
229	left = count;
230	for (i = 0; left > 0 && i < N_OUT_URB; i++) {
231		todo = left;
232		if (todo > OUT_BUFLEN)
233			todo = OUT_BUFLEN;
234
235		this_urb = portdata->out_urbs[i];
236		if (test_and_set_bit(i, &portdata->out_busy)) {
237			if (time_before(jiffies,
238					portdata->tx_start_time[i] + 10 * HZ))
239				continue;
240			usb_unlink_urb(this_urb);
241			continue;
242		}
243		dev_dbg(&port->dev, "%s: endpoint %d buf %d\n", __func__,
244			usb_pipeendpoint(this_urb->pipe), i);
245
246		err = usb_autopm_get_interface_async(port->serial->interface);
247		if (err < 0) {
248			clear_bit(i, &portdata->out_busy);
249			break;
250		}
251
252		/* send the data */
253		memcpy(this_urb->transfer_buffer, buf, todo);
254		this_urb->transfer_buffer_length = todo;
255
256		spin_lock_irqsave(&intfdata->susp_lock, flags);
257		if (intfdata->suspended) {
258			usb_anchor_urb(this_urb, &portdata->delayed);
259			spin_unlock_irqrestore(&intfdata->susp_lock, flags);
260		} else {
261			intfdata->in_flight++;
262			spin_unlock_irqrestore(&intfdata->susp_lock, flags);
263			err = usb_submit_urb(this_urb, GFP_ATOMIC);
264			if (err) {
265				dev_err(&port->dev,
266					"%s: submit urb %d failed: %d\n",
267					__func__, i, err);
268				clear_bit(i, &portdata->out_busy);
269				spin_lock_irqsave(&intfdata->susp_lock, flags);
270				intfdata->in_flight--;
271				spin_unlock_irqrestore(&intfdata->susp_lock,
272						       flags);
273				usb_autopm_put_interface_async(port->serial->interface);
274				break;
275			}
276		}
277
278		portdata->tx_start_time[i] = jiffies;
279		buf += todo;
280		left -= todo;
281	}
282
283	count -= left;
284	dev_dbg(&port->dev, "%s: wrote (did %d)\n", __func__, count);
285	return count;
286}
287EXPORT_SYMBOL(usb_wwan_write);
288
289static void usb_wwan_indat_callback(struct urb *urb)
290{
291	int err;
292	int endpoint;
293	struct usb_serial_port *port;
294	struct device *dev;
295	unsigned char *data = urb->transfer_buffer;
296	int status = urb->status;
297
298	endpoint = usb_pipeendpoint(urb->pipe);
299	port = urb->context;
300	dev = &port->dev;
301
302	if (status) {
303		dev_dbg(dev, "%s: nonzero status: %d on endpoint %02x.\n",
304			__func__, status, endpoint);
305	} else {
306		if (urb->actual_length) {
307			tty_insert_flip_string(&port->port, data,
308					urb->actual_length);
309			tty_flip_buffer_push(&port->port);
310		} else
311			dev_dbg(dev, "%s: empty read urb received\n", __func__);
312	}
313	/* Resubmit urb so we continue receiving */
314	err = usb_submit_urb(urb, GFP_ATOMIC);
315	if (err) {
316		if (err != -EPERM && err != -ENODEV) {
317			dev_err(dev, "%s: resubmit read urb failed. (%d)\n",
318				__func__, err);
319			/* busy also in error unless we are killed */
320			usb_mark_last_busy(port->serial->dev);
321		}
322	} else {
323		usb_mark_last_busy(port->serial->dev);
324	}
325}
326
327static 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	port = urb->context;
335	intfdata = usb_get_serial_data(port->serial);
336
337	usb_serial_port_softint(port);
338	usb_autopm_put_interface_async(port->serial->interface);
339	portdata = usb_get_serial_port_data(port);
340	spin_lock(&intfdata->susp_lock);
341	intfdata->in_flight--;
342	spin_unlock(&intfdata->susp_lock);
343
344	for (i = 0; i < N_OUT_URB; ++i) {
345		if (portdata->out_urbs[i] == urb) {
346			smp_mb__before_atomic();
347			clear_bit(i, &portdata->out_busy);
348			break;
349		}
350	}
351}
352
353int usb_wwan_write_room(struct tty_struct *tty)
354{
355	struct usb_serial_port *port = tty->driver_data;
356	struct usb_wwan_port_private *portdata;
357	int i;
358	int data_len = 0;
359	struct urb *this_urb;
360
361	portdata = usb_get_serial_port_data(port);
362
363	for (i = 0; i < N_OUT_URB; i++) {
364		this_urb = portdata->out_urbs[i];
365		if (this_urb && !test_bit(i, &portdata->out_busy))
366			data_len += OUT_BUFLEN;
367	}
368
369	dev_dbg(&port->dev, "%s: %d\n", __func__, data_len);
370	return data_len;
371}
372EXPORT_SYMBOL(usb_wwan_write_room);
373
374int usb_wwan_chars_in_buffer(struct tty_struct *tty)
375{
376	struct usb_serial_port *port = tty->driver_data;
377	struct usb_wwan_port_private *portdata;
378	int i;
379	int data_len = 0;
380	struct urb *this_urb;
381
382	portdata = usb_get_serial_port_data(port);
383
384	for (i = 0; i < N_OUT_URB; i++) {
385		this_urb = portdata->out_urbs[i];
386		/* FIXME: This locking is insufficient as this_urb may
387		   go unused during the test */
388		if (this_urb && test_bit(i, &portdata->out_busy))
389			data_len += this_urb->transfer_buffer_length;
390	}
391	dev_dbg(&port->dev, "%s: %d\n", __func__, data_len);
392	return data_len;
393}
394EXPORT_SYMBOL(usb_wwan_chars_in_buffer);
395
396int usb_wwan_open(struct tty_struct *tty, struct usb_serial_port *port)
397{
398	struct usb_wwan_port_private *portdata;
399	struct usb_wwan_intf_private *intfdata;
400	struct usb_serial *serial = port->serial;
401	int i, err;
402	struct urb *urb;
403
404	portdata = usb_get_serial_port_data(port);
405	intfdata = usb_get_serial_data(serial);
406
407	if (port->interrupt_in_urb) {
408		err = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
409		if (err) {
410			dev_err(&port->dev, "%s: submit int urb failed: %d\n",
411				__func__, err);
412		}
413	}
414
415	/* Start reading from the IN endpoint */
416	for (i = 0; i < N_IN_URB; i++) {
417		urb = portdata->in_urbs[i];
418		if (!urb)
419			continue;
420		err = usb_submit_urb(urb, GFP_KERNEL);
421		if (err) {
422			dev_err(&port->dev,
423				"%s: submit read urb %d failed: %d\n",
424				__func__, i, err);
425		}
426	}
427
428	spin_lock_irq(&intfdata->susp_lock);
429	if (++intfdata->open_ports == 1)
430		serial->interface->needs_remote_wakeup = 1;
431	spin_unlock_irq(&intfdata->susp_lock);
432	/* this balances a get in the generic USB serial code */
433	usb_autopm_put_interface(serial->interface);
434
435	return 0;
436}
437EXPORT_SYMBOL(usb_wwan_open);
438
439static void unbusy_queued_urb(struct urb *urb,
440					struct usb_wwan_port_private *portdata)
441{
442	int i;
443
444	for (i = 0; i < N_OUT_URB; i++) {
445		if (urb == portdata->out_urbs[i]) {
446			clear_bit(i, &portdata->out_busy);
447			break;
448		}
449	}
450}
451
452void usb_wwan_close(struct usb_serial_port *port)
453{
454	int i;
455	struct usb_serial *serial = port->serial;
456	struct usb_wwan_port_private *portdata;
457	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
458	struct urb *urb;
459
460	portdata = usb_get_serial_port_data(port);
461
462	/*
463	 * Need to take susp_lock to make sure port is not already being
464	 * resumed, but no need to hold it due to initialized
465	 */
466	spin_lock_irq(&intfdata->susp_lock);
467	if (--intfdata->open_ports == 0)
468		serial->interface->needs_remote_wakeup = 0;
469	spin_unlock_irq(&intfdata->susp_lock);
470
471	for (;;) {
472		urb = usb_get_from_anchor(&portdata->delayed);
473		if (!urb)
474			break;
475		unbusy_queued_urb(urb, portdata);
476		usb_autopm_put_interface_async(serial->interface);
477	}
478
479	for (i = 0; i < N_IN_URB; i++)
480		usb_kill_urb(portdata->in_urbs[i]);
481	for (i = 0; i < N_OUT_URB; i++)
482		usb_kill_urb(portdata->out_urbs[i]);
483	usb_kill_urb(port->interrupt_in_urb);
484
485	usb_autopm_get_interface_no_resume(serial->interface);
486}
487EXPORT_SYMBOL(usb_wwan_close);
488
489static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
490				      int endpoint,
491				      int dir, void *ctx, char *buf, int len,
492				      void (*callback) (struct urb *))
493{
494	struct usb_serial *serial = port->serial;
495	struct urb *urb;
496
497	urb = usb_alloc_urb(0, GFP_KERNEL);	/* No ISO */
498	if (!urb)
499		return NULL;
500
501	usb_fill_bulk_urb(urb, serial->dev,
502			  usb_sndbulkpipe(serial->dev, endpoint) | dir,
503			  buf, len, callback, ctx);
504
505	return urb;
506}
507
508int usb_wwan_port_probe(struct usb_serial_port *port)
509{
510	struct usb_wwan_port_private *portdata;
511	struct urb *urb;
512	u8 *buffer;
513	int i;
514
515	if (!port->bulk_in_size || !port->bulk_out_size)
516		return -ENODEV;
517
518	portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
519	if (!portdata)
520		return -ENOMEM;
521
522	init_usb_anchor(&portdata->delayed);
523
524	for (i = 0; i < N_IN_URB; i++) {
525		buffer = (u8 *)__get_free_page(GFP_KERNEL);
526		if (!buffer)
527			goto bail_out_error;
528		portdata->in_buffer[i] = buffer;
529
530		urb = usb_wwan_setup_urb(port, port->bulk_in_endpointAddress,
531						USB_DIR_IN, port,
532						buffer, IN_BUFLEN,
533						usb_wwan_indat_callback);
534		portdata->in_urbs[i] = urb;
535	}
536
537	for (i = 0; i < N_OUT_URB; i++) {
538		buffer = kmalloc(OUT_BUFLEN, GFP_KERNEL);
539		if (!buffer)
540			goto bail_out_error2;
541		portdata->out_buffer[i] = buffer;
542
543		urb = usb_wwan_setup_urb(port, port->bulk_out_endpointAddress,
544						USB_DIR_OUT, port,
545						buffer, OUT_BUFLEN,
546						usb_wwan_outdat_callback);
547		portdata->out_urbs[i] = urb;
548	}
549
550	usb_set_serial_port_data(port, portdata);
551
552	return 0;
553
554bail_out_error2:
555	for (i = 0; i < N_OUT_URB; i++) {
556		usb_free_urb(portdata->out_urbs[i]);
557		kfree(portdata->out_buffer[i]);
558	}
559bail_out_error:
560	for (i = 0; i < N_IN_URB; i++) {
561		usb_free_urb(portdata->in_urbs[i]);
562		free_page((unsigned long)portdata->in_buffer[i]);
563	}
564	kfree(portdata);
565
566	return -ENOMEM;
567}
568EXPORT_SYMBOL_GPL(usb_wwan_port_probe);
569
570int usb_wwan_port_remove(struct usb_serial_port *port)
571{
572	int i;
573	struct usb_wwan_port_private *portdata;
574
575	portdata = usb_get_serial_port_data(port);
576	usb_set_serial_port_data(port, NULL);
577
578	for (i = 0; i < N_IN_URB; 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_free_urb(portdata->out_urbs[i]);
584		kfree(portdata->out_buffer[i]);
585	}
586
587	kfree(portdata);
588
589	return 0;
590}
591EXPORT_SYMBOL(usb_wwan_port_remove);
592
593#ifdef CONFIG_PM
594static void stop_urbs(struct usb_serial *serial)
595{
596	int i, j;
597	struct usb_serial_port *port;
598	struct usb_wwan_port_private *portdata;
599
600	for (i = 0; i < serial->num_ports; ++i) {
601		port = serial->port[i];
602		portdata = usb_get_serial_port_data(port);
603		if (!portdata)
604			continue;
605		for (j = 0; j < N_IN_URB; j++)
606			usb_kill_urb(portdata->in_urbs[j]);
607		for (j = 0; j < N_OUT_URB; j++)
608			usb_kill_urb(portdata->out_urbs[j]);
609		usb_kill_urb(port->interrupt_in_urb);
610	}
611}
612
613int usb_wwan_suspend(struct usb_serial *serial, pm_message_t message)
614{
615	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
616
617	spin_lock_irq(&intfdata->susp_lock);
618	if (PMSG_IS_AUTO(message)) {
619		if (intfdata->in_flight) {
620			spin_unlock_irq(&intfdata->susp_lock);
621			return -EBUSY;
622		}
623	}
624	intfdata->suspended = 1;
625	spin_unlock_irq(&intfdata->susp_lock);
626
627	stop_urbs(serial);
628
629	return 0;
630}
631EXPORT_SYMBOL(usb_wwan_suspend);
632
633/* Caller must hold susp_lock. */
634static int usb_wwan_submit_delayed_urbs(struct usb_serial_port *port)
635{
636	struct usb_serial *serial = port->serial;
637	struct usb_wwan_intf_private *data = usb_get_serial_data(serial);
638	struct usb_wwan_port_private *portdata;
639	struct urb *urb;
640	int err_count = 0;
641	int err;
642
643	portdata = usb_get_serial_port_data(port);
644
645	for (;;) {
646		urb = usb_get_from_anchor(&portdata->delayed);
647		if (!urb)
648			break;
649
650		err = usb_submit_urb(urb, GFP_ATOMIC);
651		if (err) {
652			dev_err(&port->dev, "%s: submit urb failed: %d\n",
653					__func__, err);
654			err_count++;
655			unbusy_queued_urb(urb, portdata);
656			usb_autopm_put_interface_async(serial->interface);
657			continue;
658		}
659		data->in_flight++;
660	}
661
662	if (err_count)
663		return -EIO;
664
665	return 0;
666}
667
668int usb_wwan_resume(struct usb_serial *serial)
669{
670	int i, j;
671	struct usb_serial_port *port;
672	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
673	struct usb_wwan_port_private *portdata;
674	struct urb *urb;
675	int err;
676	int err_count = 0;
677
678	spin_lock_irq(&intfdata->susp_lock);
679	for (i = 0; i < serial->num_ports; i++) {
680		port = serial->port[i];
681
682		if (!tty_port_initialized(&port->port))
683			continue;
684
685		portdata = usb_get_serial_port_data(port);
686
687		if (port->interrupt_in_urb) {
688			err = usb_submit_urb(port->interrupt_in_urb,
689					GFP_ATOMIC);
690			if (err) {
691				dev_err(&port->dev,
692					"%s: submit int urb failed: %d\n",
693					__func__, err);
694				err_count++;
695			}
696		}
697
698		err = usb_wwan_submit_delayed_urbs(port);
699		if (err)
700			err_count++;
701
702		for (j = 0; j < N_IN_URB; j++) {
703			urb = portdata->in_urbs[j];
704			err = usb_submit_urb(urb, GFP_ATOMIC);
705			if (err < 0) {
706				dev_err(&port->dev,
707					"%s: submit read urb %d failed: %d\n",
708					__func__, i, err);
709				err_count++;
710			}
711		}
712	}
713	intfdata->suspended = 0;
714	spin_unlock_irq(&intfdata->susp_lock);
715
716	if (err_count)
717		return -EIO;
718
719	return 0;
720}
721EXPORT_SYMBOL(usb_wwan_resume);
722#endif
723
724MODULE_AUTHOR(DRIVER_AUTHOR);
725MODULE_DESCRIPTION(DRIVER_DESC);
726MODULE_LICENSE("GPL");