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 #include <linux/module.h>
18
19 /*** our ioctls ***/
20
if_lock(struct cardstate * cs,int * arg)21 static 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 gigaset_schedule_event(cs);
49
50 wait_event(cs->waitqueue, !cs->waiting);
51
52 if (cs->cmd_result >= 0) {
53 *arg = cs->cmd_result;
54 return 0;
55 }
56
57 return cs->cmd_result;
58 }
59
if_version(struct cardstate * cs,unsigned arg[4])60 static int if_version(struct cardstate *cs, unsigned arg[4])
61 {
62 static const unsigned version[4] = GIG_VERSION;
63 static const unsigned compat[4] = GIG_COMPAT;
64 unsigned cmd = arg[0];
65
66 gig_dbg(DEBUG_IF, "%u: if_version (%d)", cs->minor_index, cmd);
67
68 switch (cmd) {
69 case GIGVER_DRIVER:
70 memcpy(arg, version, sizeof version);
71 return 0;
72 case GIGVER_COMPAT:
73 memcpy(arg, compat, sizeof compat);
74 return 0;
75 case GIGVER_FWBASE:
76 cs->waiting = 1;
77 if (!gigaset_add_event(cs, &cs->at_state, EV_IF_VER,
78 NULL, 0, arg)) {
79 cs->waiting = 0;
80 return -ENOMEM;
81 }
82 gigaset_schedule_event(cs);
83
84 wait_event(cs->waitqueue, !cs->waiting);
85
86 if (cs->cmd_result >= 0)
87 return 0;
88
89 return cs->cmd_result;
90 default:
91 return -EINVAL;
92 }
93 }
94
if_config(struct cardstate * cs,int * arg)95 static int if_config(struct cardstate *cs, int *arg)
96 {
97 gig_dbg(DEBUG_IF, "%u: if_config (%d)", cs->minor_index, *arg);
98
99 if (*arg != 1)
100 return -EINVAL;
101
102 if (cs->mstate != MS_LOCKED)
103 return -EBUSY;
104
105 if (!cs->connected) {
106 pr_err("%s: not connected\n", __func__);
107 return -ENODEV;
108 }
109
110 *arg = 0;
111 return gigaset_enterconfigmode(cs);
112 }
113
114 /*** the terminal driver ***/
115
if_open(struct tty_struct * tty,struct file * filp)116 static int if_open(struct tty_struct *tty, struct file *filp)
117 {
118 struct cardstate *cs;
119
120 gig_dbg(DEBUG_IF, "%d+%d: %s()",
121 tty->driver->minor_start, tty->index, __func__);
122
123 cs = gigaset_get_cs_by_tty(tty);
124 if (!cs || !try_module_get(cs->driver->owner))
125 return -ENODEV;
126
127 if (mutex_lock_interruptible(&cs->mutex)) {
128 module_put(cs->driver->owner);
129 return -ERESTARTSYS;
130 }
131 tty->driver_data = cs;
132
133 ++cs->port.count;
134
135 if (cs->port.count == 1) {
136 tty_port_tty_set(&cs->port, tty);
137 cs->port.low_latency = 1;
138 }
139
140 mutex_unlock(&cs->mutex);
141 return 0;
142 }
143
if_close(struct tty_struct * tty,struct file * filp)144 static void if_close(struct tty_struct *tty, struct file *filp)
145 {
146 struct cardstate *cs = tty->driver_data;
147
148 if (!cs) { /* happens if we didn't find cs in open */
149 gig_dbg(DEBUG_IF, "%s: no cardstate", __func__);
150 return;
151 }
152
153 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
154
155 mutex_lock(&cs->mutex);
156
157 if (!cs->connected)
158 gig_dbg(DEBUG_IF, "not connected"); /* nothing to do */
159 else if (!cs->port.count)
160 dev_warn(cs->dev, "%s: device not opened\n", __func__);
161 else if (!--cs->port.count)
162 tty_port_tty_set(&cs->port, NULL);
163
164 mutex_unlock(&cs->mutex);
165
166 module_put(cs->driver->owner);
167 }
168
if_ioctl(struct tty_struct * tty,unsigned int cmd,unsigned long arg)169 static int if_ioctl(struct tty_struct *tty,
170 unsigned int cmd, unsigned long arg)
171 {
172 struct cardstate *cs = tty->driver_data;
173 int retval = -ENODEV;
174 int int_arg;
175 unsigned char buf[6];
176 unsigned version[4];
177
178 gig_dbg(DEBUG_IF, "%u: %s(0x%x)", cs->minor_index, __func__, cmd);
179
180 if (mutex_lock_interruptible(&cs->mutex))
181 return -ERESTARTSYS;
182
183 if (!cs->connected) {
184 gig_dbg(DEBUG_IF, "not connected");
185 retval = -ENODEV;
186 } else {
187 retval = 0;
188 switch (cmd) {
189 case GIGASET_REDIR:
190 retval = get_user(int_arg, (int __user *) arg);
191 if (retval >= 0)
192 retval = if_lock(cs, &int_arg);
193 if (retval >= 0)
194 retval = put_user(int_arg, (int __user *) arg);
195 break;
196 case GIGASET_CONFIG:
197 retval = get_user(int_arg, (int __user *) arg);
198 if (retval >= 0)
199 retval = if_config(cs, &int_arg);
200 if (retval >= 0)
201 retval = put_user(int_arg, (int __user *) arg);
202 break;
203 case GIGASET_BRKCHARS:
204 retval = copy_from_user(&buf,
205 (const unsigned char __user *) arg, 6)
206 ? -EFAULT : 0;
207 if (retval >= 0) {
208 gigaset_dbg_buffer(DEBUG_IF, "GIGASET_BRKCHARS",
209 6, (const unsigned char *) arg);
210 retval = cs->ops->brkchars(cs, buf);
211 }
212 break;
213 case GIGASET_VERSION:
214 retval = copy_from_user(version,
215 (unsigned __user *) arg, sizeof version)
216 ? -EFAULT : 0;
217 if (retval >= 0)
218 retval = if_version(cs, version);
219 if (retval >= 0)
220 retval = copy_to_user((unsigned __user *) arg,
221 version, sizeof version)
222 ? -EFAULT : 0;
223 break;
224 default:
225 gig_dbg(DEBUG_IF, "%s: arg not supported - 0x%04x",
226 __func__, cmd);
227 retval = -ENOIOCTLCMD;
228 }
229 }
230
231 mutex_unlock(&cs->mutex);
232
233 return retval;
234 }
235
if_tiocmget(struct tty_struct * tty)236 static int if_tiocmget(struct tty_struct *tty)
237 {
238 struct cardstate *cs = tty->driver_data;
239 int retval;
240
241 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
242
243 if (mutex_lock_interruptible(&cs->mutex))
244 return -ERESTARTSYS;
245
246 retval = cs->control_state & (TIOCM_RTS | TIOCM_DTR);
247
248 mutex_unlock(&cs->mutex);
249
250 return retval;
251 }
252
if_tiocmset(struct tty_struct * tty,unsigned int set,unsigned int clear)253 static int if_tiocmset(struct tty_struct *tty,
254 unsigned int set, unsigned int clear)
255 {
256 struct cardstate *cs = tty->driver_data;
257 int retval;
258 unsigned mc;
259
260 gig_dbg(DEBUG_IF, "%u: %s(0x%x, 0x%x)",
261 cs->minor_index, __func__, set, clear);
262
263 if (mutex_lock_interruptible(&cs->mutex))
264 return -ERESTARTSYS;
265
266 if (!cs->connected) {
267 gig_dbg(DEBUG_IF, "not connected");
268 retval = -ENODEV;
269 } else {
270 mc = (cs->control_state | set) & ~clear & (TIOCM_RTS | TIOCM_DTR);
271 retval = cs->ops->set_modem_ctrl(cs, cs->control_state, mc);
272 cs->control_state = mc;
273 }
274
275 mutex_unlock(&cs->mutex);
276
277 return retval;
278 }
279
if_write(struct tty_struct * tty,const unsigned char * buf,int count)280 static int if_write(struct tty_struct *tty, const unsigned char *buf, int count)
281 {
282 struct cardstate *cs = tty->driver_data;
283 struct cmdbuf_t *cb;
284 int retval;
285
286 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
287
288 if (mutex_lock_interruptible(&cs->mutex))
289 return -ERESTARTSYS;
290
291 if (!cs->connected) {
292 gig_dbg(DEBUG_IF, "not connected");
293 retval = -ENODEV;
294 goto done;
295 }
296 if (cs->mstate != MS_LOCKED) {
297 dev_warn(cs->dev, "can't write to unlocked device\n");
298 retval = -EBUSY;
299 goto done;
300 }
301 if (count <= 0) {
302 /* nothing to do */
303 retval = 0;
304 goto done;
305 }
306
307 cb = kmalloc(sizeof(struct cmdbuf_t) + count, GFP_KERNEL);
308 if (!cb) {
309 dev_err(cs->dev, "%s: out of memory\n", __func__);
310 retval = -ENOMEM;
311 goto done;
312 }
313
314 memcpy(cb->buf, buf, count);
315 cb->len = count;
316 cb->offset = 0;
317 cb->next = NULL;
318 cb->wake_tasklet = &cs->if_wake_tasklet;
319 retval = cs->ops->write_cmd(cs, cb);
320 done:
321 mutex_unlock(&cs->mutex);
322 return retval;
323 }
324
if_write_room(struct tty_struct * tty)325 static int if_write_room(struct tty_struct *tty)
326 {
327 struct cardstate *cs = tty->driver_data;
328 int retval;
329
330 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
331
332 if (mutex_lock_interruptible(&cs->mutex))
333 return -ERESTARTSYS;
334
335 if (!cs->connected) {
336 gig_dbg(DEBUG_IF, "not connected");
337 retval = -ENODEV;
338 } else if (cs->mstate != MS_LOCKED) {
339 dev_warn(cs->dev, "can't write to unlocked device\n");
340 retval = -EBUSY;
341 } else
342 retval = cs->ops->write_room(cs);
343
344 mutex_unlock(&cs->mutex);
345
346 return retval;
347 }
348
if_chars_in_buffer(struct tty_struct * tty)349 static int if_chars_in_buffer(struct tty_struct *tty)
350 {
351 struct cardstate *cs = tty->driver_data;
352 int retval = 0;
353
354 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
355
356 mutex_lock(&cs->mutex);
357
358 if (!cs->connected)
359 gig_dbg(DEBUG_IF, "not connected");
360 else if (cs->mstate != MS_LOCKED)
361 dev_warn(cs->dev, "can't write to unlocked device\n");
362 else
363 retval = cs->ops->chars_in_buffer(cs);
364
365 mutex_unlock(&cs->mutex);
366
367 return retval;
368 }
369
if_throttle(struct tty_struct * tty)370 static void if_throttle(struct tty_struct *tty)
371 {
372 struct cardstate *cs = tty->driver_data;
373
374 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
375
376 mutex_lock(&cs->mutex);
377
378 if (!cs->connected)
379 gig_dbg(DEBUG_IF, "not connected"); /* nothing to do */
380 else
381 gig_dbg(DEBUG_IF, "%s: not implemented\n", __func__);
382
383 mutex_unlock(&cs->mutex);
384 }
385
if_unthrottle(struct tty_struct * tty)386 static void if_unthrottle(struct tty_struct *tty)
387 {
388 struct cardstate *cs = tty->driver_data;
389
390 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
391
392 mutex_lock(&cs->mutex);
393
394 if (!cs->connected)
395 gig_dbg(DEBUG_IF, "not connected"); /* nothing to do */
396 else
397 gig_dbg(DEBUG_IF, "%s: not implemented\n", __func__);
398
399 mutex_unlock(&cs->mutex);
400 }
401
if_set_termios(struct tty_struct * tty,struct ktermios * old)402 static void if_set_termios(struct tty_struct *tty, struct ktermios *old)
403 {
404 struct cardstate *cs = tty->driver_data;
405 unsigned int iflag;
406 unsigned int cflag;
407 unsigned int old_cflag;
408 unsigned int control_state, new_state;
409
410 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
411
412 mutex_lock(&cs->mutex);
413
414 if (!cs->connected) {
415 gig_dbg(DEBUG_IF, "not connected");
416 goto out;
417 }
418
419 iflag = tty->termios.c_iflag;
420 cflag = tty->termios.c_cflag;
421 old_cflag = old ? old->c_cflag : cflag;
422 gig_dbg(DEBUG_IF, "%u: iflag %x cflag %x old %x",
423 cs->minor_index, iflag, cflag, old_cflag);
424
425 /* get a local copy of the current port settings */
426 control_state = cs->control_state;
427
428 /*
429 * Update baud rate.
430 * Do not attempt to cache old rates and skip settings,
431 * disconnects screw such tricks up completely.
432 * Premature optimization is the root of all evil.
433 */
434
435 /* reassert DTR and (maybe) RTS on transition from B0 */
436 if ((old_cflag & CBAUD) == B0) {
437 new_state = control_state | TIOCM_DTR;
438 /* don't set RTS if using hardware flow control */
439 if (!(old_cflag & CRTSCTS))
440 new_state |= TIOCM_RTS;
441 gig_dbg(DEBUG_IF, "%u: from B0 - set DTR%s",
442 cs->minor_index,
443 (new_state & TIOCM_RTS) ? " only" : "/RTS");
444 cs->ops->set_modem_ctrl(cs, control_state, new_state);
445 control_state = new_state;
446 }
447
448 cs->ops->baud_rate(cs, cflag & CBAUD);
449
450 if ((cflag & CBAUD) == B0) {
451 /* Drop RTS and DTR */
452 gig_dbg(DEBUG_IF, "%u: to B0 - drop DTR/RTS", cs->minor_index);
453 new_state = control_state & ~(TIOCM_DTR | TIOCM_RTS);
454 cs->ops->set_modem_ctrl(cs, control_state, new_state);
455 control_state = new_state;
456 }
457
458 /*
459 * Update line control register (LCR)
460 */
461
462 cs->ops->set_line_ctrl(cs, cflag);
463
464 /* save off the modified port settings */
465 cs->control_state = control_state;
466
467 out:
468 mutex_unlock(&cs->mutex);
469 }
470
471 static const struct tty_operations if_ops = {
472 .open = if_open,
473 .close = if_close,
474 .ioctl = if_ioctl,
475 .write = if_write,
476 .write_room = if_write_room,
477 .chars_in_buffer = if_chars_in_buffer,
478 .set_termios = if_set_termios,
479 .throttle = if_throttle,
480 .unthrottle = if_unthrottle,
481 .tiocmget = if_tiocmget,
482 .tiocmset = if_tiocmset,
483 };
484
485
486 /* wakeup tasklet for the write operation */
if_wake(unsigned long data)487 static void if_wake(unsigned long data)
488 {
489 struct cardstate *cs = (struct cardstate *)data;
490
491 tty_port_tty_wakeup(&cs->port);
492 }
493
494 /*** interface to common ***/
495
gigaset_if_init(struct cardstate * cs)496 void gigaset_if_init(struct cardstate *cs)
497 {
498 struct gigaset_driver *drv;
499
500 drv = cs->driver;
501 if (!drv->have_tty)
502 return;
503
504 tasklet_init(&cs->if_wake_tasklet, if_wake, (unsigned long) cs);
505
506 mutex_lock(&cs->mutex);
507 cs->tty_dev = tty_port_register_device(&cs->port, drv->tty,
508 cs->minor_index, NULL);
509
510 if (!IS_ERR(cs->tty_dev))
511 dev_set_drvdata(cs->tty_dev, cs);
512 else {
513 pr_warning("could not register device to the tty subsystem\n");
514 cs->tty_dev = NULL;
515 }
516 mutex_unlock(&cs->mutex);
517 }
518
gigaset_if_free(struct cardstate * cs)519 void gigaset_if_free(struct cardstate *cs)
520 {
521 struct gigaset_driver *drv;
522
523 drv = cs->driver;
524 if (!drv->have_tty)
525 return;
526
527 tasklet_disable(&cs->if_wake_tasklet);
528 tasklet_kill(&cs->if_wake_tasklet);
529 cs->tty_dev = NULL;
530 tty_unregister_device(drv->tty, cs->minor_index);
531 }
532
533 /**
534 * gigaset_if_receive() - pass a received block of data to the tty device
535 * @cs: device descriptor structure.
536 * @buffer: received data.
537 * @len: number of bytes received.
538 *
539 * Called by asyncdata/isocdata if a block of data received from the
540 * device must be sent to userspace through the ttyG* device.
541 */
gigaset_if_receive(struct cardstate * cs,unsigned char * buffer,size_t len)542 void gigaset_if_receive(struct cardstate *cs,
543 unsigned char *buffer, size_t len)
544 {
545 tty_insert_flip_string(&cs->port, buffer, len);
546 tty_flip_buffer_push(&cs->port);
547 }
548 EXPORT_SYMBOL_GPL(gigaset_if_receive);
549
550 /* gigaset_if_initdriver
551 * Initialize tty interface.
552 * parameters:
553 * drv Driver
554 * procname Name of the driver (e.g. for /proc/tty/drivers)
555 * devname Name of the device files (prefix without minor number)
556 */
gigaset_if_initdriver(struct gigaset_driver * drv,const char * procname,const char * devname)557 void gigaset_if_initdriver(struct gigaset_driver *drv, const char *procname,
558 const char *devname)
559 {
560 int ret;
561 struct tty_driver *tty;
562
563 drv->have_tty = 0;
564
565 drv->tty = tty = alloc_tty_driver(drv->minors);
566 if (tty == NULL)
567 goto enomem;
568
569 tty->type = TTY_DRIVER_TYPE_SERIAL;
570 tty->subtype = SERIAL_TYPE_NORMAL;
571 tty->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
572
573 tty->driver_name = procname;
574 tty->name = devname;
575 tty->minor_start = drv->minor;
576
577 tty->init_termios = tty_std_termios;
578 tty->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
579 tty_set_operations(tty, &if_ops);
580
581 ret = tty_register_driver(tty);
582 if (ret < 0) {
583 pr_err("error %d registering tty driver\n", ret);
584 goto error;
585 }
586 gig_dbg(DEBUG_IF, "tty driver initialized");
587 drv->have_tty = 1;
588 return;
589
590 enomem:
591 pr_err("out of memory\n");
592 error:
593 if (drv->tty)
594 put_tty_driver(drv->tty);
595 }
596
gigaset_if_freedriver(struct gigaset_driver * drv)597 void gigaset_if_freedriver(struct gigaset_driver *drv)
598 {
599 if (!drv->have_tty)
600 return;
601
602 drv->have_tty = 0;
603 tty_unregister_driver(drv->tty);
604 put_tty_driver(drv->tty);
605 }
606