interface.c revision 9d4bee2b9de9e30057a860d2d6794f874caffc5e
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.h>
17#include <linux/tty_flip.h>
18
19/*** our ioctls ***/
20
21static int if_lock(struct cardstate *cs, int *arg)
22{
23	int cmd = *arg;
24
25	gig_dbg(DEBUG_IF, "%u: if_lock (%d)", cs->minor_index, cmd);
26
27	if (cmd > 1)
28		return -EINVAL;
29
30	if (cmd < 0) {
31		*arg = cs->mstate == MS_LOCKED;
32		return 0;
33	}
34
35	if (!cmd && cs->mstate == MS_LOCKED && cs->connected) {
36		cs->ops->set_modem_ctrl(cs, 0, TIOCM_DTR|TIOCM_RTS);
37		cs->ops->baud_rate(cs, B115200);
38		cs->ops->set_line_ctrl(cs, CS8);
39		cs->control_state = TIOCM_DTR|TIOCM_RTS;
40	}
41
42	cs->waiting = 1;
43	if (!gigaset_add_event(cs, &cs->at_state, EV_IF_LOCK,
44			       NULL, cmd, NULL)) {
45		cs->waiting = 0;
46		return -ENOMEM;
47	}
48
49	gig_dbg(DEBUG_CMD, "scheduling IF_LOCK");
50	gigaset_schedule_event(cs);
51
52	wait_event(cs->waitqueue, !cs->waiting);
53
54	if (cs->cmd_result >= 0) {
55		*arg = cs->cmd_result;
56		return 0;
57	}
58
59	return cs->cmd_result;
60}
61
62static int if_version(struct cardstate *cs, unsigned arg[4])
63{
64	static const unsigned version[4] = GIG_VERSION;
65	static const unsigned compat[4] = GIG_COMPAT;
66	unsigned cmd = arg[0];
67
68	gig_dbg(DEBUG_IF, "%u: if_version (%d)", cs->minor_index, cmd);
69
70	switch (cmd) {
71	case GIGVER_DRIVER:
72		memcpy(arg, version, sizeof version);
73		return 0;
74	case GIGVER_COMPAT:
75		memcpy(arg, compat, sizeof compat);
76		return 0;
77	case GIGVER_FWBASE:
78		cs->waiting = 1;
79		if (!gigaset_add_event(cs, &cs->at_state, EV_IF_VER,
80				       NULL, 0, arg)) {
81			cs->waiting = 0;
82			return -ENOMEM;
83		}
84
85		gig_dbg(DEBUG_CMD, "scheduling IF_VER");
86		gigaset_schedule_event(cs);
87
88		wait_event(cs->waitqueue, !cs->waiting);
89
90		if (cs->cmd_result >= 0)
91			return 0;
92
93		return cs->cmd_result;
94	default:
95		return -EINVAL;
96	}
97}
98
99static int if_config(struct cardstate *cs, int *arg)
100{
101	gig_dbg(DEBUG_IF, "%u: if_config (%d)", cs->minor_index, *arg);
102
103	if (*arg != 1)
104		return -EINVAL;
105
106	if (cs->mstate != MS_LOCKED)
107		return -EBUSY;
108
109	if (!cs->connected) {
110		err("not connected!");
111		return -ENODEV;
112	}
113
114	*arg = 0;
115	return gigaset_enterconfigmode(cs);
116}
117
118/*** the terminal driver ***/
119/* stolen from usbserial and some other tty drivers */
120
121static int  if_open(struct tty_struct *tty, struct file *filp);
122static void if_close(struct tty_struct *tty, struct file *filp);
123static int  if_ioctl(struct tty_struct *tty, struct file *file,
124		     unsigned int cmd, unsigned long arg);
125static int  if_write_room(struct tty_struct *tty);
126static int  if_chars_in_buffer(struct tty_struct *tty);
127static void if_throttle(struct tty_struct *tty);
128static void if_unthrottle(struct tty_struct *tty);
129static void if_set_termios(struct tty_struct *tty, struct ktermios *old);
130static int  if_tiocmget(struct tty_struct *tty, struct file *file);
131static int  if_tiocmset(struct tty_struct *tty, struct file *file,
132			unsigned int set, unsigned int clear);
133static int  if_write(struct tty_struct *tty,
134		     const unsigned char *buf, int count);
135
136static const struct tty_operations if_ops = {
137	.open =			if_open,
138	.close =		if_close,
139	.ioctl =		if_ioctl,
140	.write =		if_write,
141	.write_room =		if_write_room,
142	.chars_in_buffer =	if_chars_in_buffer,
143	.set_termios =		if_set_termios,
144	.throttle =		if_throttle,
145	.unthrottle =		if_unthrottle,
146#if 0
147	.break_ctl =		serial_break,
148#endif
149	.tiocmget =		if_tiocmget,
150	.tiocmset =		if_tiocmset,
151};
152
153static int if_open(struct tty_struct *tty, struct file *filp)
154{
155	struct cardstate *cs;
156	unsigned long flags;
157
158	gig_dbg(DEBUG_IF, "%d+%d: %s()",
159		tty->driver->minor_start, tty->index, __func__);
160
161	tty->driver_data = NULL;
162
163	cs = gigaset_get_cs_by_tty(tty);
164	if (!cs)
165		return -ENODEV;
166
167	if (mutex_lock_interruptible(&cs->mutex))
168		return -ERESTARTSYS; // FIXME -EINTR?
169	tty->driver_data = cs;
170
171	++cs->open_count;
172
173	if (cs->open_count == 1) {
174		spin_lock_irqsave(&cs->lock, flags);
175		cs->tty = tty;
176		spin_unlock_irqrestore(&cs->lock, flags);
177		tty->low_latency = 1; //FIXME test
178	}
179
180	mutex_unlock(&cs->mutex);
181	return 0;
182}
183
184static void if_close(struct tty_struct *tty, struct file *filp)
185{
186	struct cardstate *cs;
187	unsigned long flags;
188
189	cs = (struct cardstate *) tty->driver_data;
190	if (!cs) {
191		err("cs==NULL in %s", __func__);
192		return;
193	}
194
195	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
196
197	mutex_lock(&cs->mutex);
198
199	if (!cs->open_count)
200		warn("%s: device not opened", __func__);
201	else {
202		if (!--cs->open_count) {
203			spin_lock_irqsave(&cs->lock, flags);
204			cs->tty = NULL;
205			spin_unlock_irqrestore(&cs->lock, flags);
206		}
207	}
208
209	mutex_unlock(&cs->mutex);
210}
211
212static int if_ioctl(struct tty_struct *tty, struct file *file,
213		    unsigned int cmd, unsigned long arg)
214{
215	struct cardstate *cs;
216	int retval = -ENODEV;
217	int int_arg;
218	unsigned char buf[6];
219	unsigned version[4];
220
221	cs = (struct cardstate *) tty->driver_data;
222	if (!cs) {
223		err("cs==NULL in %s", __func__);
224		return -ENODEV;
225	}
226
227	gig_dbg(DEBUG_IF, "%u: %s(0x%x)", cs->minor_index, __func__, cmd);
228
229	if (mutex_lock_interruptible(&cs->mutex))
230		return -ERESTARTSYS; // FIXME -EINTR?
231
232	if (!cs->open_count)
233		warn("%s: device not opened", __func__);
234	else {
235		retval = 0;
236		switch (cmd) {
237		case GIGASET_REDIR:
238			retval = get_user(int_arg, (int __user *) arg);
239			if (retval >= 0)
240				retval = if_lock(cs, &int_arg);
241			if (retval >= 0)
242				retval = put_user(int_arg, (int __user *) arg);
243			break;
244		case GIGASET_CONFIG:
245			retval = get_user(int_arg, (int __user *) arg);
246			if (retval >= 0)
247				retval = if_config(cs, &int_arg);
248			if (retval >= 0)
249				retval = put_user(int_arg, (int __user *) arg);
250			break;
251		case GIGASET_BRKCHARS:
252			//FIXME test if MS_LOCKED
253			if (!cs->connected) {
254				gig_dbg(DEBUG_ANY,
255				    "can't communicate with unplugged device");
256				retval = -ENODEV;
257				break;
258			}
259			retval = copy_from_user(&buf,
260					(const unsigned char __user *) arg, 6)
261				? -EFAULT : 0;
262			if (retval >= 0) {
263				gigaset_dbg_buffer(DEBUG_IF, "GIGASET_BRKCHARS",
264						6, (const unsigned char *) arg);
265				retval = cs->ops->brkchars(cs, buf);
266			}
267			break;
268		case GIGASET_VERSION:
269			retval = copy_from_user(version,
270					(unsigned __user *) arg, sizeof version)
271				? -EFAULT : 0;
272			if (retval >= 0)
273				retval = if_version(cs, version);
274			if (retval >= 0)
275				retval = copy_to_user((unsigned __user *) arg,
276						      version, sizeof version)
277					? -EFAULT : 0;
278			break;
279		default:
280			gig_dbg(DEBUG_ANY, "%s: arg not supported - 0x%04x",
281				__func__, cmd);
282			retval = -ENOIOCTLCMD;
283		}
284	}
285
286	mutex_unlock(&cs->mutex);
287
288	return retval;
289}
290
291static int if_tiocmget(struct tty_struct *tty, struct file *file)
292{
293	struct cardstate *cs;
294	int retval;
295
296	cs = (struct cardstate *) tty->driver_data;
297	if (!cs) {
298		err("cs==NULL in %s", __func__);
299		return -ENODEV;
300	}
301
302	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
303
304	if (mutex_lock_interruptible(&cs->mutex))
305		return -ERESTARTSYS; // FIXME -EINTR?
306
307	// FIXME read from device?
308	retval = cs->control_state & (TIOCM_RTS|TIOCM_DTR);
309
310	mutex_unlock(&cs->mutex);
311
312	return retval;
313}
314
315static int if_tiocmset(struct tty_struct *tty, struct file *file,
316		       unsigned int set, unsigned int clear)
317{
318	struct cardstate *cs;
319	int retval;
320	unsigned mc;
321
322	cs = (struct cardstate *) tty->driver_data;
323	if (!cs) {
324		err("cs==NULL in %s", __func__);
325		return -ENODEV;
326	}
327
328	gig_dbg(DEBUG_IF, "%u: %s(0x%x, 0x%x)",
329		cs->minor_index, __func__, set, clear);
330
331	if (mutex_lock_interruptible(&cs->mutex))
332		return -ERESTARTSYS; // FIXME -EINTR?
333
334	if (!cs->connected) {
335		gig_dbg(DEBUG_ANY, "can't communicate with unplugged device");
336		retval = -ENODEV;
337	} else {
338		mc = (cs->control_state | set) & ~clear & (TIOCM_RTS|TIOCM_DTR);
339		retval = cs->ops->set_modem_ctrl(cs, cs->control_state, mc);
340		cs->control_state = mc;
341	}
342
343	mutex_unlock(&cs->mutex);
344
345	return retval;
346}
347
348static int if_write(struct tty_struct *tty, const unsigned char *buf, int count)
349{
350	struct cardstate *cs;
351	int retval = -ENODEV;
352
353	cs = (struct cardstate *) tty->driver_data;
354	if (!cs) {
355		err("cs==NULL in %s", __func__);
356		return -ENODEV;
357	}
358
359	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
360
361	if (mutex_lock_interruptible(&cs->mutex))
362		return -ERESTARTSYS; // FIXME -EINTR?
363
364	if (!cs->open_count)
365		warn("%s: device not opened", __func__);
366	else if (cs->mstate != MS_LOCKED) {
367		warn("can't write to unlocked device");
368		retval = -EBUSY;
369	} else if (!cs->connected) {
370		gig_dbg(DEBUG_ANY, "can't write to unplugged device");
371		retval = -EBUSY; //FIXME
372	} else {
373		retval = cs->ops->write_cmd(cs, buf, count,
374					    &cs->if_wake_tasklet);
375	}
376
377	mutex_unlock(&cs->mutex);
378
379	return retval;
380}
381
382static int if_write_room(struct tty_struct *tty)
383{
384	struct cardstate *cs;
385	int retval = -ENODEV;
386
387	cs = (struct cardstate *) tty->driver_data;
388	if (!cs) {
389		err("cs==NULL in %s", __func__);
390		return -ENODEV;
391	}
392
393	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
394
395	if (mutex_lock_interruptible(&cs->mutex))
396		return -ERESTARTSYS; // FIXME -EINTR?
397
398	if (!cs->open_count)
399		warn("%s: device not opened", __func__);
400	else if (cs->mstate != MS_LOCKED) {
401		warn("can't write to unlocked device");
402		retval = -EBUSY;
403	} else if (!cs->connected) {
404		gig_dbg(DEBUG_ANY, "can't write to unplugged device");
405		retval = -EBUSY; //FIXME
406	} else
407		retval = cs->ops->write_room(cs);
408
409	mutex_unlock(&cs->mutex);
410
411	return retval;
412}
413
414static int if_chars_in_buffer(struct tty_struct *tty)
415{
416	struct cardstate *cs;
417	int retval = -ENODEV;
418
419	cs = (struct cardstate *) tty->driver_data;
420	if (!cs) {
421		err("cs==NULL in %s", __func__);
422		return -ENODEV;
423	}
424
425	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
426
427	if (mutex_lock_interruptible(&cs->mutex))
428		return -ERESTARTSYS; // FIXME -EINTR?
429
430	if (!cs->open_count)
431		warn("%s: device not opened", __func__);
432	else if (cs->mstate != MS_LOCKED) {
433		warn("can't write to unlocked device");
434		retval = -EBUSY;
435	} else if (!cs->connected) {
436		gig_dbg(DEBUG_ANY, "can't write to unplugged device");
437		retval = -EBUSY; //FIXME
438	} else
439		retval = cs->ops->chars_in_buffer(cs);
440
441	mutex_unlock(&cs->mutex);
442
443	return retval;
444}
445
446static void if_throttle(struct tty_struct *tty)
447{
448	struct cardstate *cs;
449
450	cs = (struct cardstate *) tty->driver_data;
451	if (!cs) {
452		err("cs==NULL in %s", __func__);
453		return;
454	}
455
456	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
457
458	mutex_lock(&cs->mutex);
459
460	if (!cs->open_count)
461		warn("%s: device not opened", __func__);
462	else {
463		//FIXME
464	}
465
466	mutex_unlock(&cs->mutex);
467}
468
469static void if_unthrottle(struct tty_struct *tty)
470{
471	struct cardstate *cs;
472
473	cs = (struct cardstate *) tty->driver_data;
474	if (!cs) {
475		err("cs==NULL in %s", __func__);
476		return;
477	}
478
479	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
480
481	mutex_lock(&cs->mutex);
482
483	if (!cs->open_count)
484		warn("%s: device not opened", __func__);
485	else {
486		//FIXME
487	}
488
489	mutex_unlock(&cs->mutex);
490}
491
492static void if_set_termios(struct tty_struct *tty, struct ktermios *old)
493{
494	struct cardstate *cs;
495	unsigned int iflag;
496	unsigned int cflag;
497	unsigned int old_cflag;
498	unsigned int control_state, new_state;
499
500	cs = (struct cardstate *) tty->driver_data;
501	if (!cs) {
502		err("cs==NULL in %s", __func__);
503		return;
504	}
505
506	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
507
508	mutex_lock(&cs->mutex);
509
510	if (!cs->open_count) {
511		warn("%s: device not opened", __func__);
512		goto out;
513	}
514
515	if (!cs->connected) {
516		gig_dbg(DEBUG_ANY, "can't communicate with unplugged device");
517		goto out;
518	}
519
520	// stolen from mct_u232.c
521	iflag = tty->termios->c_iflag;
522	cflag = tty->termios->c_cflag;
523	old_cflag = old ? old->c_cflag : cflag; //FIXME?
524	gig_dbg(DEBUG_IF, "%u: iflag %x cflag %x old %x",
525		cs->minor_index, iflag, cflag, old_cflag);
526
527	/* get a local copy of the current port settings */
528	control_state = cs->control_state;
529
530	/*
531	 * Update baud rate.
532	 * Do not attempt to cache old rates and skip settings,
533	 * disconnects screw such tricks up completely.
534	 * Premature optimization is the root of all evil.
535	 */
536
537	/* reassert DTR and (maybe) RTS on transition from B0 */
538	if ((old_cflag & CBAUD) == B0) {
539		new_state = control_state | TIOCM_DTR;
540		/* don't set RTS if using hardware flow control */
541		if (!(old_cflag & CRTSCTS))
542			new_state |= TIOCM_RTS;
543		gig_dbg(DEBUG_IF, "%u: from B0 - set DTR%s",
544			cs->minor_index,
545			(new_state & TIOCM_RTS) ? " only" : "/RTS");
546		cs->ops->set_modem_ctrl(cs, control_state, new_state);
547		control_state = new_state;
548	}
549
550	cs->ops->baud_rate(cs, cflag & CBAUD);
551
552	if ((cflag & CBAUD) == B0) {
553		/* Drop RTS and DTR */
554		gig_dbg(DEBUG_IF, "%u: to B0 - drop DTR/RTS", cs->minor_index);
555		new_state = control_state & ~(TIOCM_DTR | TIOCM_RTS);
556		cs->ops->set_modem_ctrl(cs, control_state, new_state);
557		control_state = new_state;
558	}
559
560	/*
561	 * Update line control register (LCR)
562	 */
563
564	cs->ops->set_line_ctrl(cs, cflag);
565
566#if 0
567	//FIXME this hangs M101 [ts 2005-03-09]
568	//FIXME do we need this?
569	/*
570	 * Set flow control: well, I do not really now how to handle DTR/RTS.
571	 * Just do what we have seen with SniffUSB on Win98.
572	 */
573	/* Drop DTR/RTS if no flow control otherwise assert */
574	gig_dbg(DEBUG_IF, "%u: control_state %x",
575		cs->minor_index, control_state);
576	new_state = control_state;
577	if ((iflag & IXOFF) || (iflag & IXON) || (cflag & CRTSCTS))
578		new_state |= TIOCM_DTR | TIOCM_RTS;
579	else
580		new_state &= ~(TIOCM_DTR | TIOCM_RTS);
581	if (new_state != control_state) {
582		gig_dbg(DEBUG_IF, "%u: new_state %x",
583			cs->minor_index, new_state);
584		gigaset_set_modem_ctrl(cs, control_state, new_state);
585		control_state = new_state;
586	}
587#endif
588
589	/* save off the modified port settings */
590	cs->control_state = control_state;
591
592out:
593	mutex_unlock(&cs->mutex);
594}
595
596
597/* wakeup tasklet for the write operation */
598static void if_wake(unsigned long data)
599{
600	struct cardstate *cs = (struct cardstate *) data;
601
602	if (cs->tty)
603		tty_wakeup(cs->tty);
604}
605
606/*** interface to common ***/
607
608void gigaset_if_init(struct cardstate *cs)
609{
610	struct gigaset_driver *drv;
611
612	drv = cs->driver;
613	if (!drv->have_tty)
614		return;
615
616	tasklet_init(&cs->if_wake_tasklet, &if_wake, (unsigned long) cs);
617
618	mutex_lock(&cs->mutex);
619	cs->tty_dev = tty_register_device(drv->tty, cs->minor_index, NULL);
620
621	if (!IS_ERR(cs->tty_dev))
622		dev_set_drvdata(cs->tty_dev, cs);
623	else {
624		warn("could not register device to the tty subsystem");
625		cs->tty_dev = NULL;
626	}
627	mutex_unlock(&cs->mutex);
628}
629
630void gigaset_if_free(struct cardstate *cs)
631{
632	struct gigaset_driver *drv;
633
634	drv = cs->driver;
635	if (!drv->have_tty)
636		return;
637
638	tasklet_disable(&cs->if_wake_tasklet);
639	tasklet_kill(&cs->if_wake_tasklet);
640	cs->tty_dev = NULL;
641	tty_unregister_device(drv->tty, cs->minor_index);
642}
643
644void gigaset_if_receive(struct cardstate *cs,
645			unsigned char *buffer, size_t len)
646{
647	unsigned long flags;
648	struct tty_struct *tty;
649
650	spin_lock_irqsave(&cs->lock, flags);
651	if ((tty = cs->tty) == NULL)
652		gig_dbg(DEBUG_ANY, "receive on closed device");
653	else {
654		tty_buffer_request_room(tty, len);
655		tty_insert_flip_string(tty, buffer, len);
656		tty_flip_buffer_push(tty);
657	}
658	spin_unlock_irqrestore(&cs->lock, flags);
659}
660EXPORT_SYMBOL_GPL(gigaset_if_receive);
661
662/* gigaset_if_initdriver
663 * Initialize tty interface.
664 * parameters:
665 *	drv		Driver
666 *	procname	Name of the driver (e.g. for /proc/tty/drivers)
667 *	devname		Name of the device files (prefix without minor number)
668 */
669void gigaset_if_initdriver(struct gigaset_driver *drv, const char *procname,
670			   const char *devname)
671{
672	unsigned minors = drv->minors;
673	int ret;
674	struct tty_driver *tty;
675
676	drv->have_tty = 0;
677
678	if ((drv->tty = alloc_tty_driver(minors)) == NULL)
679		goto enomem;
680	tty = drv->tty;
681
682	tty->magic =		TTY_DRIVER_MAGIC,
683	tty->major =		GIG_MAJOR,
684	tty->type =		TTY_DRIVER_TYPE_SERIAL,
685	tty->subtype =		SERIAL_TYPE_NORMAL,
686	tty->flags =		TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
687
688	tty->driver_name =	procname;
689	tty->name =		devname;
690	tty->minor_start =	drv->minor;
691	tty->num =		drv->minors;
692
693	tty->owner =		THIS_MODULE;
694
695	tty->init_termios          = tty_std_termios; //FIXME
696	tty->init_termios.c_cflag  = B9600 | CS8 | CREAD | HUPCL | CLOCAL; //FIXME
697	tty_set_operations(tty, &if_ops);
698
699	ret = tty_register_driver(tty);
700	if (ret < 0) {
701		warn("failed to register tty driver (error %d)", ret);
702		goto error;
703	}
704	gig_dbg(DEBUG_IF, "tty driver initialized");
705	drv->have_tty = 1;
706	return;
707
708enomem:
709	warn("could not allocate tty structures");
710error:
711	if (drv->tty)
712		put_tty_driver(drv->tty);
713}
714
715void gigaset_if_freedriver(struct gigaset_driver *drv)
716{
717	if (!drv->have_tty)
718		return;
719
720	drv->have_tty = 0;
721	tty_unregister_driver(drv->tty);
722	put_tty_driver(drv->tty);
723}
724