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v5.9
  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
274		/* don't resubmit on fatal errors */
275		if (status == -ESHUTDOWN || status == -ENOENT)
276			return;
277	} else {
278		if (urb->actual_length) {
279			tty_insert_flip_string(&port->port, data,
280					urb->actual_length);
281			tty_flip_buffer_push(&port->port);
282		} else
283			dev_dbg(dev, "%s: empty read urb received\n", __func__);
284	}
285	/* Resubmit urb so we continue receiving */
286	err = usb_submit_urb(urb, GFP_ATOMIC);
287	if (err) {
288		if (err != -EPERM && err != -ENODEV) {
289			dev_err(dev, "%s: resubmit read urb failed. (%d)\n",
290				__func__, err);
291			/* busy also in error unless we are killed */
292			usb_mark_last_busy(port->serial->dev);
293		}
294	} else {
295		usb_mark_last_busy(port->serial->dev);
296	}
297}
298
299static void usb_wwan_outdat_callback(struct urb *urb)
300{
301	struct usb_serial_port *port;
302	struct usb_wwan_port_private *portdata;
303	struct usb_wwan_intf_private *intfdata;
304	unsigned long flags;
305	int i;
306
307	port = urb->context;
308	intfdata = usb_get_serial_data(port->serial);
309
310	usb_serial_port_softint(port);
311	usb_autopm_put_interface_async(port->serial->interface);
312	portdata = usb_get_serial_port_data(port);
313	spin_lock_irqsave(&intfdata->susp_lock, flags);
314	intfdata->in_flight--;
315	spin_unlock_irqrestore(&intfdata->susp_lock, flags);
316
317	for (i = 0; i < N_OUT_URB; ++i) {
318		if (portdata->out_urbs[i] == urb) {
319			smp_mb__before_atomic();
320			clear_bit(i, &portdata->out_busy);
321			break;
322		}
323	}
324}
325
326int usb_wwan_write_room(struct tty_struct *tty)
327{
328	struct usb_serial_port *port = tty->driver_data;
329	struct usb_wwan_port_private *portdata;
330	int i;
331	int data_len = 0;
332	struct urb *this_urb;
333
334	portdata = usb_get_serial_port_data(port);
335
336	for (i = 0; i < N_OUT_URB; i++) {
337		this_urb = portdata->out_urbs[i];
338		if (this_urb && !test_bit(i, &portdata->out_busy))
339			data_len += OUT_BUFLEN;
340	}
341
342	dev_dbg(&port->dev, "%s: %d\n", __func__, data_len);
343	return data_len;
344}
345EXPORT_SYMBOL(usb_wwan_write_room);
346
347int usb_wwan_chars_in_buffer(struct tty_struct *tty)
348{
349	struct usb_serial_port *port = tty->driver_data;
350	struct usb_wwan_port_private *portdata;
351	int i;
352	int data_len = 0;
353	struct urb *this_urb;
354
355	portdata = usb_get_serial_port_data(port);
356
357	for (i = 0; i < N_OUT_URB; i++) {
358		this_urb = portdata->out_urbs[i];
359		/* FIXME: This locking is insufficient as this_urb may
360		   go unused during the test */
361		if (this_urb && test_bit(i, &portdata->out_busy))
362			data_len += this_urb->transfer_buffer_length;
363	}
364	dev_dbg(&port->dev, "%s: %d\n", __func__, data_len);
365	return data_len;
366}
367EXPORT_SYMBOL(usb_wwan_chars_in_buffer);
368
369int usb_wwan_open(struct tty_struct *tty, struct usb_serial_port *port)
370{
371	struct usb_wwan_port_private *portdata;
372	struct usb_wwan_intf_private *intfdata;
373	struct usb_serial *serial = port->serial;
374	int i, err;
375	struct urb *urb;
376
377	portdata = usb_get_serial_port_data(port);
378	intfdata = usb_get_serial_data(serial);
379
380	if (port->interrupt_in_urb) {
381		err = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
382		if (err) {
383			dev_err(&port->dev, "%s: submit int urb failed: %d\n",
384				__func__, err);
385		}
386	}
387
388	/* Start reading from the IN endpoint */
389	for (i = 0; i < N_IN_URB; i++) {
390		urb = portdata->in_urbs[i];
391		if (!urb)
392			continue;
393		err = usb_submit_urb(urb, GFP_KERNEL);
394		if (err) {
395			dev_err(&port->dev,
396				"%s: submit read urb %d failed: %d\n",
397				__func__, i, err);
398		}
399	}
400
401	spin_lock_irq(&intfdata->susp_lock);
402	if (++intfdata->open_ports == 1)
403		serial->interface->needs_remote_wakeup = 1;
404	spin_unlock_irq(&intfdata->susp_lock);
405	/* this balances a get in the generic USB serial code */
406	usb_autopm_put_interface(serial->interface);
407
408	return 0;
409}
410EXPORT_SYMBOL(usb_wwan_open);
411
412static void unbusy_queued_urb(struct urb *urb,
413					struct usb_wwan_port_private *portdata)
414{
415	int i;
416
417	for (i = 0; i < N_OUT_URB; i++) {
418		if (urb == portdata->out_urbs[i]) {
419			clear_bit(i, &portdata->out_busy);
420			break;
421		}
422	}
423}
424
425void usb_wwan_close(struct usb_serial_port *port)
426{
427	int i;
428	struct usb_serial *serial = port->serial;
429	struct usb_wwan_port_private *portdata;
430	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
431	struct urb *urb;
432
433	portdata = usb_get_serial_port_data(port);
434
435	/*
436	 * Need to take susp_lock to make sure port is not already being
437	 * resumed, but no need to hold it due to initialized
438	 */
439	spin_lock_irq(&intfdata->susp_lock);
440	if (--intfdata->open_ports == 0)
441		serial->interface->needs_remote_wakeup = 0;
442	spin_unlock_irq(&intfdata->susp_lock);
443
444	for (;;) {
445		urb = usb_get_from_anchor(&portdata->delayed);
446		if (!urb)
447			break;
448		unbusy_queued_urb(urb, portdata);
449		usb_autopm_put_interface_async(serial->interface);
450	}
451
452	for (i = 0; i < N_IN_URB; i++)
453		usb_kill_urb(portdata->in_urbs[i]);
454	for (i = 0; i < N_OUT_URB; i++)
455		usb_kill_urb(portdata->out_urbs[i]);
456	usb_kill_urb(port->interrupt_in_urb);
457
458	usb_autopm_get_interface_no_resume(serial->interface);
459}
460EXPORT_SYMBOL(usb_wwan_close);
461
462static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
463				      int endpoint,
464				      int dir, void *ctx, char *buf, int len,
465				      void (*callback) (struct urb *))
466{
467	struct usb_serial *serial = port->serial;
468	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
469	struct urb *urb;
470
471	urb = usb_alloc_urb(0, GFP_KERNEL);	/* No ISO */
472	if (!urb)
473		return NULL;
474
475	usb_fill_bulk_urb(urb, serial->dev,
476			  usb_sndbulkpipe(serial->dev, endpoint) | dir,
477			  buf, len, callback, ctx);
478
479	if (intfdata->use_zlp && dir == USB_DIR_OUT)
480		urb->transfer_flags |= URB_ZERO_PACKET;
481
482	return urb;
483}
484
485int usb_wwan_port_probe(struct usb_serial_port *port)
486{
487	struct usb_wwan_port_private *portdata;
488	struct urb *urb;
489	u8 *buffer;
490	int i;
491
492	if (!port->bulk_in_size || !port->bulk_out_size)
493		return -ENODEV;
494
495	portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
496	if (!portdata)
497		return -ENOMEM;
498
499	init_usb_anchor(&portdata->delayed);
500
501	for (i = 0; i < N_IN_URB; i++) {
502		buffer = (u8 *)__get_free_page(GFP_KERNEL);
503		if (!buffer)
504			goto bail_out_error;
505		portdata->in_buffer[i] = buffer;
506
507		urb = usb_wwan_setup_urb(port, port->bulk_in_endpointAddress,
508						USB_DIR_IN, port,
509						buffer, IN_BUFLEN,
510						usb_wwan_indat_callback);
511		portdata->in_urbs[i] = urb;
512	}
513
514	for (i = 0; i < N_OUT_URB; i++) {
515		buffer = kmalloc(OUT_BUFLEN, GFP_KERNEL);
516		if (!buffer)
517			goto bail_out_error2;
518		portdata->out_buffer[i] = buffer;
519
520		urb = usb_wwan_setup_urb(port, port->bulk_out_endpointAddress,
521						USB_DIR_OUT, port,
522						buffer, OUT_BUFLEN,
523						usb_wwan_outdat_callback);
524		portdata->out_urbs[i] = urb;
525	}
526
527	usb_set_serial_port_data(port, portdata);
528
529	return 0;
530
531bail_out_error2:
532	for (i = 0; i < N_OUT_URB; i++) {
533		usb_free_urb(portdata->out_urbs[i]);
534		kfree(portdata->out_buffer[i]);
535	}
536bail_out_error:
537	for (i = 0; i < N_IN_URB; i++) {
538		usb_free_urb(portdata->in_urbs[i]);
539		free_page((unsigned long)portdata->in_buffer[i]);
540	}
541	kfree(portdata);
542
543	return -ENOMEM;
544}
545EXPORT_SYMBOL_GPL(usb_wwan_port_probe);
546
547int usb_wwan_port_remove(struct usb_serial_port *port)
548{
549	int i;
550	struct usb_wwan_port_private *portdata;
551
552	portdata = usb_get_serial_port_data(port);
553	usb_set_serial_port_data(port, NULL);
554
555	for (i = 0; i < N_IN_URB; i++) {
556		usb_free_urb(portdata->in_urbs[i]);
557		free_page((unsigned long)portdata->in_buffer[i]);
558	}
559	for (i = 0; i < N_OUT_URB; i++) {
560		usb_free_urb(portdata->out_urbs[i]);
561		kfree(portdata->out_buffer[i]);
562	}
563
564	kfree(portdata);
565
566	return 0;
567}
568EXPORT_SYMBOL(usb_wwan_port_remove);
569
570#ifdef CONFIG_PM
571static void stop_urbs(struct usb_serial *serial)
572{
573	int i, j;
574	struct usb_serial_port *port;
575	struct usb_wwan_port_private *portdata;
576
577	for (i = 0; i < serial->num_ports; ++i) {
578		port = serial->port[i];
579		portdata = usb_get_serial_port_data(port);
580		if (!portdata)
581			continue;
582		for (j = 0; j < N_IN_URB; j++)
583			usb_kill_urb(portdata->in_urbs[j]);
584		for (j = 0; j < N_OUT_URB; j++)
585			usb_kill_urb(portdata->out_urbs[j]);
586		usb_kill_urb(port->interrupt_in_urb);
587	}
588}
589
590int usb_wwan_suspend(struct usb_serial *serial, pm_message_t message)
591{
592	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
593
594	spin_lock_irq(&intfdata->susp_lock);
595	if (PMSG_IS_AUTO(message)) {
596		if (intfdata->in_flight) {
597			spin_unlock_irq(&intfdata->susp_lock);
598			return -EBUSY;
599		}
600	}
601	intfdata->suspended = 1;
602	spin_unlock_irq(&intfdata->susp_lock);
603
604	stop_urbs(serial);
605
606	return 0;
607}
608EXPORT_SYMBOL(usb_wwan_suspend);
609
610/* Caller must hold susp_lock. */
611static int usb_wwan_submit_delayed_urbs(struct usb_serial_port *port)
612{
613	struct usb_serial *serial = port->serial;
614	struct usb_wwan_intf_private *data = usb_get_serial_data(serial);
615	struct usb_wwan_port_private *portdata;
616	struct urb *urb;
617	int err_count = 0;
618	int err;
619
620	portdata = usb_get_serial_port_data(port);
621
622	for (;;) {
623		urb = usb_get_from_anchor(&portdata->delayed);
624		if (!urb)
625			break;
626
627		err = usb_submit_urb(urb, GFP_ATOMIC);
628		if (err) {
629			dev_err(&port->dev, "%s: submit urb failed: %d\n",
630					__func__, err);
631			err_count++;
632			unbusy_queued_urb(urb, portdata);
633			usb_autopm_put_interface_async(serial->interface);
634			continue;
635		}
636		data->in_flight++;
637	}
638
639	if (err_count)
640		return -EIO;
641
642	return 0;
643}
644
645int usb_wwan_resume(struct usb_serial *serial)
646{
647	int i, j;
648	struct usb_serial_port *port;
649	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
650	struct usb_wwan_port_private *portdata;
651	struct urb *urb;
652	int err;
653	int err_count = 0;
654
655	spin_lock_irq(&intfdata->susp_lock);
656	for (i = 0; i < serial->num_ports; i++) {
657		port = serial->port[i];
658
659		if (!tty_port_initialized(&port->port))
660			continue;
661
662		portdata = usb_get_serial_port_data(port);
663
664		if (port->interrupt_in_urb) {
665			err = usb_submit_urb(port->interrupt_in_urb,
666					GFP_ATOMIC);
667			if (err) {
668				dev_err(&port->dev,
669					"%s: submit int urb failed: %d\n",
670					__func__, err);
671				err_count++;
672			}
673		}
674
675		err = usb_wwan_submit_delayed_urbs(port);
676		if (err)
677			err_count++;
678
679		for (j = 0; j < N_IN_URB; j++) {
680			urb = portdata->in_urbs[j];
681			err = usb_submit_urb(urb, GFP_ATOMIC);
682			if (err < 0) {
683				dev_err(&port->dev,
684					"%s: submit read urb %d failed: %d\n",
685					__func__, i, err);
686				err_count++;
687			}
688		}
689	}
690	intfdata->suspended = 0;
691	spin_unlock_irq(&intfdata->susp_lock);
692
693	if (err_count)
694		return -EIO;
695
696	return 0;
697}
698EXPORT_SYMBOL(usb_wwan_resume);
699#endif
700
701MODULE_AUTHOR(DRIVER_AUTHOR);
702MODULE_DESCRIPTION(DRIVER_DESC);
703MODULE_LICENSE("GPL v2");
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");