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/drivers/isdn/gigaset/interface.c

https://bitbucket.org/ndreys/linux-sunxi
C | 721 lines | 538 code | 135 blank | 48 comment | 100 complexity | f87f8ca095495e698a8805e3ab22c312 MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.0, AGPL-1.0
  1/*
  2 * interface to user space for the gigaset driver
  3 *
  4 * Copyright (c) 2004 by Hansjoerg Lipp <hjlipp@web.de>
  5 *
  6 * =====================================================================
  7 *    This program is free software; you can redistribute it and/or
  8 *    modify it under the terms of the GNU General Public License as
  9 *    published by the Free Software Foundation; either version 2 of
 10 *    the License, or (at your option) any later version.
 11 * =====================================================================
 12 */
 13
 14#include "gigaset.h"
 15#include <linux/gigaset_dev.h>
 16#include <linux/tty_flip.h>
 17
 18/*** our ioctls ***/
 19
 20static int if_lock(struct cardstate *cs, int *arg)
 21{
 22	int cmd = *arg;
 23
 24	gig_dbg(DEBUG_IF, "%u: if_lock (%d)", cs->minor_index, cmd);
 25
 26	if (cmd > 1)
 27		return -EINVAL;
 28
 29	if (cmd < 0) {
 30		*arg = cs->mstate == MS_LOCKED;
 31		return 0;
 32	}
 33
 34	if (!cmd && cs->mstate == MS_LOCKED && cs->connected) {
 35		cs->ops->set_modem_ctrl(cs, 0, TIOCM_DTR|TIOCM_RTS);
 36		cs->ops->baud_rate(cs, B115200);
 37		cs->ops->set_line_ctrl(cs, CS8);
 38		cs->control_state = TIOCM_DTR|TIOCM_RTS;
 39	}
 40
 41	cs->waiting = 1;
 42	if (!gigaset_add_event(cs, &cs->at_state, EV_IF_LOCK,
 43			       NULL, cmd, NULL)) {
 44		cs->waiting = 0;
 45		return -ENOMEM;
 46	}
 47	gigaset_schedule_event(cs);
 48
 49	wait_event(cs->waitqueue, !cs->waiting);
 50
 51	if (cs->cmd_result >= 0) {
 52		*arg = cs->cmd_result;
 53		return 0;
 54	}
 55
 56	return cs->cmd_result;
 57}
 58
 59static int if_version(struct cardstate *cs, unsigned arg[4])
 60{
 61	static const unsigned version[4] = GIG_VERSION;
 62	static const unsigned compat[4] = GIG_COMPAT;
 63	unsigned cmd = arg[0];
 64
 65	gig_dbg(DEBUG_IF, "%u: if_version (%d)", cs->minor_index, cmd);
 66
 67	switch (cmd) {
 68	case GIGVER_DRIVER:
 69		memcpy(arg, version, sizeof version);
 70		return 0;
 71	case GIGVER_COMPAT:
 72		memcpy(arg, compat, sizeof compat);
 73		return 0;
 74	case GIGVER_FWBASE:
 75		cs->waiting = 1;
 76		if (!gigaset_add_event(cs, &cs->at_state, EV_IF_VER,
 77				       NULL, 0, arg)) {
 78			cs->waiting = 0;
 79			return -ENOMEM;
 80		}
 81		gigaset_schedule_event(cs);
 82
 83		wait_event(cs->waitqueue, !cs->waiting);
 84
 85		if (cs->cmd_result >= 0)
 86			return 0;
 87
 88		return cs->cmd_result;
 89	default:
 90		return -EINVAL;
 91	}
 92}
 93
 94static int if_config(struct cardstate *cs, int *arg)
 95{
 96	gig_dbg(DEBUG_IF, "%u: if_config (%d)", cs->minor_index, *arg);
 97
 98	if (*arg != 1)
 99		return -EINVAL;
100
101	if (cs->mstate != MS_LOCKED)
102		return -EBUSY;
103
104	if (!cs->connected) {
105		pr_err("%s: not connected\n", __func__);
106		return -ENODEV;
107	}
108
109	*arg = 0;
110	return gigaset_enterconfigmode(cs);
111}
112
113/*** the terminal driver ***/
114/* stolen from usbserial and some other tty drivers */
115
116static int  if_open(struct tty_struct *tty, struct file *filp);
117static void if_close(struct tty_struct *tty, struct file *filp);
118static int  if_ioctl(struct tty_struct *tty,
119		     unsigned int cmd, unsigned long arg);
120static int  if_write_room(struct tty_struct *tty);
121static int  if_chars_in_buffer(struct tty_struct *tty);
122static void if_throttle(struct tty_struct *tty);
123static void if_unthrottle(struct tty_struct *tty);
124static void if_set_termios(struct tty_struct *tty, struct ktermios *old);
125static int  if_tiocmget(struct tty_struct *tty);
126static int  if_tiocmset(struct tty_struct *tty,
127			unsigned int set, unsigned int clear);
128static int  if_write(struct tty_struct *tty,
129		     const unsigned char *buf, int count);
130
131static const struct tty_operations if_ops = {
132	.open =			if_open,
133	.close =		if_close,
134	.ioctl =		if_ioctl,
135	.write =		if_write,
136	.write_room =		if_write_room,
137	.chars_in_buffer =	if_chars_in_buffer,
138	.set_termios =		if_set_termios,
139	.throttle =		if_throttle,
140	.unthrottle =		if_unthrottle,
141	.tiocmget =		if_tiocmget,
142	.tiocmset =		if_tiocmset,
143};
144
145static int if_open(struct tty_struct *tty, struct file *filp)
146{
147	struct cardstate *cs;
148	unsigned long flags;
149
150	gig_dbg(DEBUG_IF, "%d+%d: %s()",
151		tty->driver->minor_start, tty->index, __func__);
152
153	tty->driver_data = NULL;
154
155	cs = gigaset_get_cs_by_tty(tty);
156	if (!cs || !try_module_get(cs->driver->owner))
157		return -ENODEV;
158
159	if (mutex_lock_interruptible(&cs->mutex)) {
160		module_put(cs->driver->owner);
161		return -ERESTARTSYS;
162	}
163	tty->driver_data = cs;
164
165	++cs->open_count;
166
167	if (cs->open_count == 1) {
168		spin_lock_irqsave(&cs->lock, flags);
169		cs->tty = tty;
170		spin_unlock_irqrestore(&cs->lock, flags);
171		tty->low_latency = 1;
172	}
173
174	mutex_unlock(&cs->mutex);
175	return 0;
176}
177
178static void if_close(struct tty_struct *tty, struct file *filp)
179{
180	struct cardstate *cs;
181	unsigned long flags;
182
183	cs = (struct cardstate *) tty->driver_data;
184	if (!cs) {
185		pr_err("%s: no cardstate\n", __func__);
186		return;
187	}
188
189	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
190
191	mutex_lock(&cs->mutex);
192
193	if (!cs->connected)
194		gig_dbg(DEBUG_IF, "not connected");	/* nothing to do */
195	else if (!cs->open_count)
196		dev_warn(cs->dev, "%s: device not opened\n", __func__);
197	else {
198		if (!--cs->open_count) {
199			spin_lock_irqsave(&cs->lock, flags);
200			cs->tty = NULL;
201			spin_unlock_irqrestore(&cs->lock, flags);
202		}
203	}
204
205	mutex_unlock(&cs->mutex);
206
207	module_put(cs->driver->owner);
208}
209
210static int if_ioctl(struct tty_struct *tty,
211		    unsigned int cmd, unsigned long arg)
212{
213	struct cardstate *cs;
214	int retval = -ENODEV;
215	int int_arg;
216	unsigned char buf[6];
217	unsigned version[4];
218
219	cs = (struct cardstate *) tty->driver_data;
220	if (!cs) {
221		pr_err("%s: no cardstate\n", __func__);
222		return -ENODEV;
223	}
224
225	gig_dbg(DEBUG_IF, "%u: %s(0x%x)", cs->minor_index, __func__, cmd);
226
227	if (mutex_lock_interruptible(&cs->mutex))
228		return -ERESTARTSYS;
229
230	if (!cs->connected) {
231		gig_dbg(DEBUG_IF, "not connected");
232		retval = -ENODEV;
233	} else if (!cs->open_count)
234		dev_warn(cs->dev, "%s: device not opened\n", __func__);
235	else {
236		retval = 0;
237		switch (cmd) {
238		case GIGASET_REDIR:
239			retval = get_user(int_arg, (int __user *) arg);
240			if (retval >= 0)
241				retval = if_lock(cs, &int_arg);
242			if (retval >= 0)
243				retval = put_user(int_arg, (int __user *) arg);
244			break;
245		case GIGASET_CONFIG:
246			retval = get_user(int_arg, (int __user *) arg);
247			if (retval >= 0)
248				retval = if_config(cs, &int_arg);
249			if (retval >= 0)
250				retval = put_user(int_arg, (int __user *) arg);
251			break;
252		case GIGASET_BRKCHARS:
253			retval = copy_from_user(&buf,
254					(const unsigned char __user *) arg, 6)
255				? -EFAULT : 0;
256			if (retval >= 0) {
257				gigaset_dbg_buffer(DEBUG_IF, "GIGASET_BRKCHARS",
258						6, (const unsigned char *) arg);
259				retval = cs->ops->brkchars(cs, buf);
260			}
261			break;
262		case GIGASET_VERSION:
263			retval = copy_from_user(version,
264					(unsigned __user *) arg, sizeof version)
265				? -EFAULT : 0;
266			if (retval >= 0)
267				retval = if_version(cs, version);
268			if (retval >= 0)
269				retval = copy_to_user((unsigned __user *) arg,
270						      version, sizeof version)
271					? -EFAULT : 0;
272			break;
273		default:
274			gig_dbg(DEBUG_IF, "%s: arg not supported - 0x%04x",
275				__func__, cmd);
276			retval = -ENOIOCTLCMD;
277		}
278	}
279
280	mutex_unlock(&cs->mutex);
281
282	return retval;
283}
284
285static int if_tiocmget(struct tty_struct *tty)
286{
287	struct cardstate *cs;
288	int retval;
289
290	cs = (struct cardstate *) tty->driver_data;
291	if (!cs) {
292		pr_err("%s: no cardstate\n", __func__);
293		return -ENODEV;
294	}
295
296	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
297
298	if (mutex_lock_interruptible(&cs->mutex))
299		return -ERESTARTSYS;
300
301	retval = cs->control_state & (TIOCM_RTS|TIOCM_DTR);
302
303	mutex_unlock(&cs->mutex);
304
305	return retval;
306}
307
308static int if_tiocmset(struct tty_struct *tty,
309		       unsigned int set, unsigned int clear)
310{
311	struct cardstate *cs;
312	int retval;
313	unsigned mc;
314
315	cs = (struct cardstate *) tty->driver_data;
316	if (!cs) {
317		pr_err("%s: no cardstate\n", __func__);
318		return -ENODEV;
319	}
320
321	gig_dbg(DEBUG_IF, "%u: %s(0x%x, 0x%x)",
322		cs->minor_index, __func__, set, clear);
323
324	if (mutex_lock_interruptible(&cs->mutex))
325		return -ERESTARTSYS;
326
327	if (!cs->connected) {
328		gig_dbg(DEBUG_IF, "not connected");
329		retval = -ENODEV;
330	} else {
331		mc = (cs->control_state | set) & ~clear & (TIOCM_RTS|TIOCM_DTR);
332		retval = cs->ops->set_modem_ctrl(cs, cs->control_state, mc);
333		cs->control_state = mc;
334	}
335
336	mutex_unlock(&cs->mutex);
337
338	return retval;
339}
340
341static int if_write(struct tty_struct *tty, const unsigned char *buf, int count)
342{
343	struct cardstate *cs;
344	struct cmdbuf_t *cb;
345	int retval;
346
347	cs = (struct cardstate *) tty->driver_data;
348	if (!cs) {
349		pr_err("%s: no cardstate\n", __func__);
350		return -ENODEV;
351	}
352
353	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
354
355	if (mutex_lock_interruptible(&cs->mutex))
356		return -ERESTARTSYS;
357
358	if (!cs->connected) {
359		gig_dbg(DEBUG_IF, "not connected");
360		retval = -ENODEV;
361		goto done;
362	}
363	if (!cs->open_count) {
364		dev_warn(cs->dev, "%s: device not opened\n", __func__);
365		retval = -ENODEV;
366		goto done;
367	}
368	if (cs->mstate != MS_LOCKED) {
369		dev_warn(cs->dev, "can't write to unlocked device\n");
370		retval = -EBUSY;
371		goto done;
372	}
373	if (count <= 0) {
374		/* nothing to do */
375		retval = 0;
376		goto done;
377	}
378
379	cb = kmalloc(sizeof(struct cmdbuf_t) + count, GFP_KERNEL);
380	if (!cb) {
381		dev_err(cs->dev, "%s: out of memory\n", __func__);
382		retval = -ENOMEM;
383		goto done;
384	}
385
386	memcpy(cb->buf, buf, count);
387	cb->len = count;
388	cb->offset = 0;
389	cb->next = NULL;
390	cb->wake_tasklet = &cs->if_wake_tasklet;
391	retval = cs->ops->write_cmd(cs, cb);
392done:
393	mutex_unlock(&cs->mutex);
394	return retval;
395}
396
397static int if_write_room(struct tty_struct *tty)
398{
399	struct cardstate *cs;
400	int retval = -ENODEV;
401
402	cs = (struct cardstate *) tty->driver_data;
403	if (!cs) {
404		pr_err("%s: no cardstate\n", __func__);
405		return -ENODEV;
406	}
407
408	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
409
410	if (mutex_lock_interruptible(&cs->mutex))
411		return -ERESTARTSYS;
412
413	if (!cs->connected) {
414		gig_dbg(DEBUG_IF, "not connected");
415		retval = -ENODEV;
416	} else if (!cs->open_count)
417		dev_warn(cs->dev, "%s: device not opened\n", __func__);
418	else if (cs->mstate != MS_LOCKED) {
419		dev_warn(cs->dev, "can't write to unlocked device\n");
420		retval = -EBUSY;
421	} else
422		retval = cs->ops->write_room(cs);
423
424	mutex_unlock(&cs->mutex);
425
426	return retval;
427}
428
429static int if_chars_in_buffer(struct tty_struct *tty)
430{
431	struct cardstate *cs;
432	int retval = 0;
433
434	cs = (struct cardstate *) tty->driver_data;
435	if (!cs) {
436		pr_err("%s: no cardstate\n", __func__);
437		return 0;
438	}
439
440	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
441
442	mutex_lock(&cs->mutex);
443
444	if (!cs->connected)
445		gig_dbg(DEBUG_IF, "not connected");
446	else if (!cs->open_count)
447		dev_warn(cs->dev, "%s: device not opened\n", __func__);
448	else if (cs->mstate != MS_LOCKED)
449		dev_warn(cs->dev, "can't write to unlocked device\n");
450	else
451		retval = cs->ops->chars_in_buffer(cs);
452
453	mutex_unlock(&cs->mutex);
454
455	return retval;
456}
457
458static void if_throttle(struct tty_struct *tty)
459{
460	struct cardstate *cs;
461
462	cs = (struct cardstate *) tty->driver_data;
463	if (!cs) {
464		pr_err("%s: no cardstate\n", __func__);
465		return;
466	}
467
468	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
469
470	mutex_lock(&cs->mutex);
471
472	if (!cs->connected)
473		gig_dbg(DEBUG_IF, "not connected");	/* nothing to do */
474	else if (!cs->open_count)
475		dev_warn(cs->dev, "%s: device not opened\n", __func__);
476	else
477		gig_dbg(DEBUG_IF, "%s: not implemented\n", __func__);
478
479	mutex_unlock(&cs->mutex);
480}
481
482static void if_unthrottle(struct tty_struct *tty)
483{
484	struct cardstate *cs;
485
486	cs = (struct cardstate *) tty->driver_data;
487	if (!cs) {
488		pr_err("%s: no cardstate\n", __func__);
489		return;
490	}
491
492	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
493
494	mutex_lock(&cs->mutex);
495
496	if (!cs->connected)
497		gig_dbg(DEBUG_IF, "not connected");	/* nothing to do */
498	else if (!cs->open_count)
499		dev_warn(cs->dev, "%s: device not opened\n", __func__);
500	else
501		gig_dbg(DEBUG_IF, "%s: not implemented\n", __func__);
502
503	mutex_unlock(&cs->mutex);
504}
505
506static void if_set_termios(struct tty_struct *tty, struct ktermios *old)
507{
508	struct cardstate *cs;
509	unsigned int iflag;
510	unsigned int cflag;
511	unsigned int old_cflag;
512	unsigned int control_state, new_state;
513
514	cs = (struct cardstate *) tty->driver_data;
515	if (!cs) {
516		pr_err("%s: no cardstate\n", __func__);
517		return;
518	}
519
520	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
521
522	mutex_lock(&cs->mutex);
523
524	if (!cs->connected) {
525		gig_dbg(DEBUG_IF, "not connected");
526		goto out;
527	}
528
529	if (!cs->open_count) {
530		dev_warn(cs->dev, "%s: device not opened\n", __func__);
531		goto out;
532	}
533
534	iflag = tty->termios->c_iflag;
535	cflag = tty->termios->c_cflag;
536	old_cflag = old ? old->c_cflag : cflag;
537	gig_dbg(DEBUG_IF, "%u: iflag %x cflag %x old %x",
538		cs->minor_index, iflag, cflag, old_cflag);
539
540	/* get a local copy of the current port settings */
541	control_state = cs->control_state;
542
543	/*
544	 * Update baud rate.
545	 * Do not attempt to cache old rates and skip settings,
546	 * disconnects screw such tricks up completely.
547	 * Premature optimization is the root of all evil.
548	 */
549
550	/* reassert DTR and (maybe) RTS on transition from B0 */
551	if ((old_cflag & CBAUD) == B0) {
552		new_state = control_state | TIOCM_DTR;
553		/* don't set RTS if using hardware flow control */
554		if (!(old_cflag & CRTSCTS))
555			new_state |= TIOCM_RTS;
556		gig_dbg(DEBUG_IF, "%u: from B0 - set DTR%s",
557			cs->minor_index,
558			(new_state & TIOCM_RTS) ? " only" : "/RTS");
559		cs->ops->set_modem_ctrl(cs, control_state, new_state);
560		control_state = new_state;
561	}
562
563	cs->ops->baud_rate(cs, cflag & CBAUD);
564
565	if ((cflag & CBAUD) == B0) {
566		/* Drop RTS and DTR */
567		gig_dbg(DEBUG_IF, "%u: to B0 - drop DTR/RTS", cs->minor_index);
568		new_state = control_state & ~(TIOCM_DTR | TIOCM_RTS);
569		cs->ops->set_modem_ctrl(cs, control_state, new_state);
570		control_state = new_state;
571	}
572
573	/*
574	 * Update line control register (LCR)
575	 */
576
577	cs->ops->set_line_ctrl(cs, cflag);
578
579	/* save off the modified port settings */
580	cs->control_state = control_state;
581
582out:
583	mutex_unlock(&cs->mutex);
584}
585
586
587/* wakeup tasklet for the write operation */
588static void if_wake(unsigned long data)
589{
590	struct cardstate *cs = (struct cardstate *) data;
591
592	if (cs->tty)
593		tty_wakeup(cs->tty);
594}
595
596/*** interface to common ***/
597
598void gigaset_if_init(struct cardstate *cs)
599{
600	struct gigaset_driver *drv;
601
602	drv = cs->driver;
603	if (!drv->have_tty)
604		return;
605
606	tasklet_init(&cs->if_wake_tasklet, if_wake, (unsigned long) cs);
607
608	mutex_lock(&cs->mutex);
609	cs->tty_dev = tty_register_device(drv->tty, cs->minor_index, NULL);
610
611	if (!IS_ERR(cs->tty_dev))
612		dev_set_drvdata(cs->tty_dev, cs);
613	else {
614		pr_warning("could not register device to the tty subsystem\n");
615		cs->tty_dev = NULL;
616	}
617	mutex_unlock(&cs->mutex);
618}
619
620void gigaset_if_free(struct cardstate *cs)
621{
622	struct gigaset_driver *drv;
623
624	drv = cs->driver;
625	if (!drv->have_tty)
626		return;
627
628	tasklet_disable(&cs->if_wake_tasklet);
629	tasklet_kill(&cs->if_wake_tasklet);
630	cs->tty_dev = NULL;
631	tty_unregister_device(drv->tty, cs->minor_index);
632}
633
634/**
635 * gigaset_if_receive() - pass a received block of data to the tty device
636 * @cs:		device descriptor structure.
637 * @buffer:	received data.
638 * @len:	number of bytes received.
639 *
640 * Called by asyncdata/isocdata if a block of data received from the
641 * device must be sent to userspace through the ttyG* device.
642 */
643void gigaset_if_receive(struct cardstate *cs,
644			unsigned char *buffer, size_t len)
645{
646	unsigned long flags;
647	struct tty_struct *tty;
648
649	spin_lock_irqsave(&cs->lock, flags);
650	tty = cs->tty;
651	if (tty == NULL)
652		gig_dbg(DEBUG_IF, "receive on closed device");
653	else {
654		tty_insert_flip_string(tty, buffer, len);
655		tty_flip_buffer_push(tty);
656	}
657	spin_unlock_irqrestore(&cs->lock, flags);
658}
659EXPORT_SYMBOL_GPL(gigaset_if_receive);
660
661/* gigaset_if_initdriver
662 * Initialize tty interface.
663 * parameters:
664 *	drv		Driver
665 *	procname	Name of the driver (e.g. for /proc/tty/drivers)
666 *	devname		Name of the device files (prefix without minor number)
667 */
668void gigaset_if_initdriver(struct gigaset_driver *drv, const char *procname,
669			   const char *devname)
670{
671	unsigned minors = drv->minors;
672	int ret;
673	struct tty_driver *tty;
674
675	drv->have_tty = 0;
676
677	drv->tty = tty = alloc_tty_driver(minors);
678	if (tty == NULL)
679		goto enomem;
680
681	tty->magic =		TTY_DRIVER_MAGIC,
682	tty->type =		TTY_DRIVER_TYPE_SERIAL,
683	tty->subtype =		SERIAL_TYPE_NORMAL,
684	tty->flags =		TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
685
686	tty->driver_name =	procname;
687	tty->name =		devname;
688	tty->minor_start =	drv->minor;
689	tty->num =		drv->minors;
690
691	tty->owner =		THIS_MODULE;
692
693	tty->init_termios          = tty_std_termios;
694	tty->init_termios.c_cflag  = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
695	tty_set_operations(tty, &if_ops);
696
697	ret = tty_register_driver(tty);
698	if (ret < 0) {
699		pr_err("error %d registering tty driver\n", ret);
700		goto error;
701	}
702	gig_dbg(DEBUG_IF, "tty driver initialized");
703	drv->have_tty = 1;
704	return;
705
706enomem:
707	pr_err("out of memory\n");
708error:
709	if (drv->tty)
710		put_tty_driver(drv->tty);
711}
712
713void gigaset_if_freedriver(struct gigaset_driver *drv)
714{
715	if (!drv->have_tty)
716		return;
717
718	drv->have_tty = 0;
719	tty_unregister_driver(drv->tty);
720	put_tty_driver(drv->tty);
721}