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 /* stolen from usbserial and some other tty drivers */
116
117 static int if_open(struct tty_struct *tty, struct file *filp);
118 static void if_close(struct tty_struct *tty, struct file *filp);
119 static int if_ioctl(struct tty_struct *tty,
120 unsigned int cmd, unsigned long arg);
121 static int if_write_room(struct tty_struct *tty);
122 static int if_chars_in_buffer(struct tty_struct *tty);
123 static void if_throttle(struct tty_struct *tty);
124 static void if_unthrottle(struct tty_struct *tty);
125 static void if_set_termios(struct tty_struct *tty, struct ktermios *old);
126 static int if_tiocmget(struct tty_struct *tty);
127 static int if_tiocmset(struct tty_struct *tty,
128 unsigned int set, unsigned int clear);
129 static int if_write(struct tty_struct *tty,
130 const unsigned char *buf, int count);
131
132 static const struct tty_operations if_ops = {
133 .open = if_open,
134 .close = if_close,
135 .ioctl = if_ioctl,
136 .write = if_write,
137 .write_room = if_write_room,
138 .chars_in_buffer = if_chars_in_buffer,
139 .set_termios = if_set_termios,
140 .throttle = if_throttle,
141 .unthrottle = if_unthrottle,
142 .tiocmget = if_tiocmget,
143 .tiocmset = if_tiocmset,
144 };
145
if_open(struct tty_struct * tty,struct file * filp)146 static int if_open(struct tty_struct *tty, struct file *filp)
147 {
148 struct cardstate *cs;
149
150 gig_dbg(DEBUG_IF, "%d+%d: %s()",
151 tty->driver->minor_start, tty->index, __func__);
152
153 cs = gigaset_get_cs_by_tty(tty);
154 if (!cs || !try_module_get(cs->driver->owner))
155 return -ENODEV;
156
157 if (mutex_lock_interruptible(&cs->mutex)) {
158 module_put(cs->driver->owner);
159 return -ERESTARTSYS;
160 }
161 tty->driver_data = cs;
162
163 ++cs->port.count;
164
165 if (cs->port.count == 1) {
166 tty_port_tty_set(&cs->port, tty);
167 tty->low_latency = 1;
168 }
169
170 mutex_unlock(&cs->mutex);
171 return 0;
172 }
173
if_close(struct tty_struct * tty,struct file * filp)174 static void if_close(struct tty_struct *tty, struct file *filp)
175 {
176 struct cardstate *cs = tty->driver_data;
177
178 if (!cs) { /* happens if we didn't find cs in open */
179 gig_dbg(DEBUG_IF, "%s: no cardstate", __func__);
180 return;
181 }
182
183 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
184
185 mutex_lock(&cs->mutex);
186
187 if (!cs->connected)
188 gig_dbg(DEBUG_IF, "not connected"); /* nothing to do */
189 else if (!cs->port.count)
190 dev_warn(cs->dev, "%s: device not opened\n", __func__);
191 else if (!--cs->port.count)
192 tty_port_tty_set(&cs->port, NULL);
193
194 mutex_unlock(&cs->mutex);
195
196 module_put(cs->driver->owner);
197 }
198
if_ioctl(struct tty_struct * tty,unsigned int cmd,unsigned long arg)199 static int if_ioctl(struct tty_struct *tty,
200 unsigned int cmd, unsigned long arg)
201 {
202 struct cardstate *cs = tty->driver_data;
203 int retval = -ENODEV;
204 int int_arg;
205 unsigned char buf[6];
206 unsigned version[4];
207
208 gig_dbg(DEBUG_IF, "%u: %s(0x%x)", cs->minor_index, __func__, cmd);
209
210 if (mutex_lock_interruptible(&cs->mutex))
211 return -ERESTARTSYS;
212
213 if (!cs->connected) {
214 gig_dbg(DEBUG_IF, "not connected");
215 retval = -ENODEV;
216 } else {
217 retval = 0;
218 switch (cmd) {
219 case GIGASET_REDIR:
220 retval = get_user(int_arg, (int __user *) arg);
221 if (retval >= 0)
222 retval = if_lock(cs, &int_arg);
223 if (retval >= 0)
224 retval = put_user(int_arg, (int __user *) arg);
225 break;
226 case GIGASET_CONFIG:
227 retval = get_user(int_arg, (int __user *) arg);
228 if (retval >= 0)
229 retval = if_config(cs, &int_arg);
230 if (retval >= 0)
231 retval = put_user(int_arg, (int __user *) arg);
232 break;
233 case GIGASET_BRKCHARS:
234 retval = copy_from_user(&buf,
235 (const unsigned char __user *) arg, 6)
236 ? -EFAULT : 0;
237 if (retval >= 0) {
238 gigaset_dbg_buffer(DEBUG_IF, "GIGASET_BRKCHARS",
239 6, (const unsigned char *) arg);
240 retval = cs->ops->brkchars(cs, buf);
241 }
242 break;
243 case GIGASET_VERSION:
244 retval = copy_from_user(version,
245 (unsigned __user *) arg, sizeof version)
246 ? -EFAULT : 0;
247 if (retval >= 0)
248 retval = if_version(cs, version);
249 if (retval >= 0)
250 retval = copy_to_user((unsigned __user *) arg,
251 version, sizeof version)
252 ? -EFAULT : 0;
253 break;
254 default:
255 gig_dbg(DEBUG_IF, "%s: arg not supported - 0x%04x",
256 __func__, cmd);
257 retval = -ENOIOCTLCMD;
258 }
259 }
260
261 mutex_unlock(&cs->mutex);
262
263 return retval;
264 }
265
if_tiocmget(struct tty_struct * tty)266 static int if_tiocmget(struct tty_struct *tty)
267 {
268 struct cardstate *cs = tty->driver_data;
269 int retval;
270
271 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
272
273 if (mutex_lock_interruptible(&cs->mutex))
274 return -ERESTARTSYS;
275
276 retval = cs->control_state & (TIOCM_RTS | TIOCM_DTR);
277
278 mutex_unlock(&cs->mutex);
279
280 return retval;
281 }
282
if_tiocmset(struct tty_struct * tty,unsigned int set,unsigned int clear)283 static int if_tiocmset(struct tty_struct *tty,
284 unsigned int set, unsigned int clear)
285 {
286 struct cardstate *cs = tty->driver_data;
287 int retval;
288 unsigned mc;
289
290 gig_dbg(DEBUG_IF, "%u: %s(0x%x, 0x%x)",
291 cs->minor_index, __func__, set, clear);
292
293 if (mutex_lock_interruptible(&cs->mutex))
294 return -ERESTARTSYS;
295
296 if (!cs->connected) {
297 gig_dbg(DEBUG_IF, "not connected");
298 retval = -ENODEV;
299 } else {
300 mc = (cs->control_state | set) & ~clear & (TIOCM_RTS | TIOCM_DTR);
301 retval = cs->ops->set_modem_ctrl(cs, cs->control_state, mc);
302 cs->control_state = mc;
303 }
304
305 mutex_unlock(&cs->mutex);
306
307 return retval;
308 }
309
if_write(struct tty_struct * tty,const unsigned char * buf,int count)310 static int if_write(struct tty_struct *tty, const unsigned char *buf, int count)
311 {
312 struct cardstate *cs = tty->driver_data;
313 struct cmdbuf_t *cb;
314 int retval;
315
316 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
317
318 if (mutex_lock_interruptible(&cs->mutex))
319 return -ERESTARTSYS;
320
321 if (!cs->connected) {
322 gig_dbg(DEBUG_IF, "not connected");
323 retval = -ENODEV;
324 goto done;
325 }
326 if (cs->mstate != MS_LOCKED) {
327 dev_warn(cs->dev, "can't write to unlocked device\n");
328 retval = -EBUSY;
329 goto done;
330 }
331 if (count <= 0) {
332 /* nothing to do */
333 retval = 0;
334 goto done;
335 }
336
337 cb = kmalloc(sizeof(struct cmdbuf_t) + count, GFP_KERNEL);
338 if (!cb) {
339 dev_err(cs->dev, "%s: out of memory\n", __func__);
340 retval = -ENOMEM;
341 goto done;
342 }
343
344 memcpy(cb->buf, buf, count);
345 cb->len = count;
346 cb->offset = 0;
347 cb->next = NULL;
348 cb->wake_tasklet = &cs->if_wake_tasklet;
349 retval = cs->ops->write_cmd(cs, cb);
350 done:
351 mutex_unlock(&cs->mutex);
352 return retval;
353 }
354
if_write_room(struct tty_struct * tty)355 static int if_write_room(struct tty_struct *tty)
356 {
357 struct cardstate *cs = tty->driver_data;
358 int retval = -ENODEV;
359
360 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
361
362 if (mutex_lock_interruptible(&cs->mutex))
363 return -ERESTARTSYS;
364
365 if (!cs->connected) {
366 gig_dbg(DEBUG_IF, "not connected");
367 retval = -ENODEV;
368 } else if (cs->mstate != MS_LOCKED) {
369 dev_warn(cs->dev, "can't write to unlocked device\n");
370 retval = -EBUSY;
371 } else
372 retval = cs->ops->write_room(cs);
373
374 mutex_unlock(&cs->mutex);
375
376 return retval;
377 }
378
if_chars_in_buffer(struct tty_struct * tty)379 static int if_chars_in_buffer(struct tty_struct *tty)
380 {
381 struct cardstate *cs = tty->driver_data;
382 int retval = 0;
383
384 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
385
386 mutex_lock(&cs->mutex);
387
388 if (!cs->connected)
389 gig_dbg(DEBUG_IF, "not connected");
390 else if (cs->mstate != MS_LOCKED)
391 dev_warn(cs->dev, "can't write to unlocked device\n");
392 else
393 retval = cs->ops->chars_in_buffer(cs);
394
395 mutex_unlock(&cs->mutex);
396
397 return retval;
398 }
399
if_throttle(struct tty_struct * tty)400 static void if_throttle(struct tty_struct *tty)
401 {
402 struct cardstate *cs = tty->driver_data;
403
404 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
405
406 mutex_lock(&cs->mutex);
407
408 if (!cs->connected)
409 gig_dbg(DEBUG_IF, "not connected"); /* nothing to do */
410 else
411 gig_dbg(DEBUG_IF, "%s: not implemented\n", __func__);
412
413 mutex_unlock(&cs->mutex);
414 }
415
if_unthrottle(struct tty_struct * tty)416 static void if_unthrottle(struct tty_struct *tty)
417 {
418 struct cardstate *cs = tty->driver_data;
419
420 gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
421
422 mutex_lock(&cs->mutex);
423
424 if (!cs->connected)
425 gig_dbg(DEBUG_IF, "not connected"); /* nothing to do */
426 else
427 gig_dbg(DEBUG_IF, "%s: not implemented\n", __func__);
428
429 mutex_unlock(&cs->mutex);
430 }
431
if_set_termios(struct tty_struct * tty,struct ktermios * old)432 static void if_set_termios(struct tty_struct *tty, struct ktermios *old)
433 {
434 struct cardstate *cs = tty->driver_data;
435 unsigned int iflag;
436 unsigned int cflag;
437 unsigned int old_cflag;
438 unsigned int control_state, new_state;
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 goto out;
447 }
448
449 iflag = tty->termios->c_iflag;
450 cflag = tty->termios->c_cflag;
451 old_cflag = old ? old->c_cflag : cflag;
452 gig_dbg(DEBUG_IF, "%u: iflag %x cflag %x old %x",
453 cs->minor_index, iflag, cflag, old_cflag);
454
455 /* get a local copy of the current port settings */
456 control_state = cs->control_state;
457
458 /*
459 * Update baud rate.
460 * Do not attempt to cache old rates and skip settings,
461 * disconnects screw such tricks up completely.
462 * Premature optimization is the root of all evil.
463 */
464
465 /* reassert DTR and (maybe) RTS on transition from B0 */
466 if ((old_cflag & CBAUD) == B0) {
467 new_state = control_state | TIOCM_DTR;
468 /* don't set RTS if using hardware flow control */
469 if (!(old_cflag & CRTSCTS))
470 new_state |= TIOCM_RTS;
471 gig_dbg(DEBUG_IF, "%u: from B0 - set DTR%s",
472 cs->minor_index,
473 (new_state & TIOCM_RTS) ? " only" : "/RTS");
474 cs->ops->set_modem_ctrl(cs, control_state, new_state);
475 control_state = new_state;
476 }
477
478 cs->ops->baud_rate(cs, cflag & CBAUD);
479
480 if ((cflag & CBAUD) == B0) {
481 /* Drop RTS and DTR */
482 gig_dbg(DEBUG_IF, "%u: to B0 - drop DTR/RTS", cs->minor_index);
483 new_state = control_state & ~(TIOCM_DTR | TIOCM_RTS);
484 cs->ops->set_modem_ctrl(cs, control_state, new_state);
485 control_state = new_state;
486 }
487
488 /*
489 * Update line control register (LCR)
490 */
491
492 cs->ops->set_line_ctrl(cs, cflag);
493
494 /* save off the modified port settings */
495 cs->control_state = control_state;
496
497 out:
498 mutex_unlock(&cs->mutex);
499 }
500
501
502 /* wakeup tasklet for the write operation */
if_wake(unsigned long data)503 static void if_wake(unsigned long data)
504 {
505 struct cardstate *cs = (struct cardstate *)data;
506 struct tty_struct *tty = tty_port_tty_get(&cs->port);
507
508 if (tty) {
509 tty_wakeup(tty);
510 tty_kref_put(tty);
511 }
512 }
513
514 /*** interface to common ***/
515
gigaset_if_init(struct cardstate * cs)516 void gigaset_if_init(struct cardstate *cs)
517 {
518 struct gigaset_driver *drv;
519
520 drv = cs->driver;
521 if (!drv->have_tty)
522 return;
523
524 tasklet_init(&cs->if_wake_tasklet, if_wake, (unsigned long) cs);
525
526 mutex_lock(&cs->mutex);
527 cs->tty_dev = tty_register_device(drv->tty, cs->minor_index, NULL);
528
529 if (!IS_ERR(cs->tty_dev))
530 dev_set_drvdata(cs->tty_dev, cs);
531 else {
532 pr_warning("could not register device to the tty subsystem\n");
533 cs->tty_dev = NULL;
534 }
535 mutex_unlock(&cs->mutex);
536 }
537
gigaset_if_free(struct cardstate * cs)538 void gigaset_if_free(struct cardstate *cs)
539 {
540 struct gigaset_driver *drv;
541
542 drv = cs->driver;
543 if (!drv->have_tty)
544 return;
545
546 tasklet_disable(&cs->if_wake_tasklet);
547 tasklet_kill(&cs->if_wake_tasklet);
548 cs->tty_dev = NULL;
549 tty_unregister_device(drv->tty, cs->minor_index);
550 }
551
552 /**
553 * gigaset_if_receive() - pass a received block of data to the tty device
554 * @cs: device descriptor structure.
555 * @buffer: received data.
556 * @len: number of bytes received.
557 *
558 * Called by asyncdata/isocdata if a block of data received from the
559 * device must be sent to userspace through the ttyG* device.
560 */
gigaset_if_receive(struct cardstate * cs,unsigned char * buffer,size_t len)561 void gigaset_if_receive(struct cardstate *cs,
562 unsigned char *buffer, size_t len)
563 {
564 struct tty_struct *tty = tty_port_tty_get(&cs->port);
565
566 if (tty == NULL) {
567 gig_dbg(DEBUG_IF, "receive on closed device");
568 return;
569 }
570
571 tty_insert_flip_string(tty, buffer, len);
572 tty_flip_buffer_push(tty);
573 tty_kref_put(tty);
574 }
575 EXPORT_SYMBOL_GPL(gigaset_if_receive);
576
577 /* gigaset_if_initdriver
578 * Initialize tty interface.
579 * parameters:
580 * drv Driver
581 * procname Name of the driver (e.g. for /proc/tty/drivers)
582 * devname Name of the device files (prefix without minor number)
583 */
gigaset_if_initdriver(struct gigaset_driver * drv,const char * procname,const char * devname)584 void gigaset_if_initdriver(struct gigaset_driver *drv, const char *procname,
585 const char *devname)
586 {
587 int ret;
588 struct tty_driver *tty;
589
590 drv->have_tty = 0;
591
592 drv->tty = tty = alloc_tty_driver(drv->minors);
593 if (tty == NULL)
594 goto enomem;
595
596 tty->type = TTY_DRIVER_TYPE_SERIAL;
597 tty->subtype = SERIAL_TYPE_NORMAL;
598 tty->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
599
600 tty->driver_name = procname;
601 tty->name = devname;
602 tty->minor_start = drv->minor;
603
604 tty->init_termios = tty_std_termios;
605 tty->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
606 tty_set_operations(tty, &if_ops);
607
608 ret = tty_register_driver(tty);
609 if (ret < 0) {
610 pr_err("error %d registering tty driver\n", ret);
611 goto error;
612 }
613 gig_dbg(DEBUG_IF, "tty driver initialized");
614 drv->have_tty = 1;
615 return;
616
617 enomem:
618 pr_err("out of memory\n");
619 error:
620 if (drv->tty)
621 put_tty_driver(drv->tty);
622 }
623
gigaset_if_freedriver(struct gigaset_driver * drv)624 void gigaset_if_freedriver(struct gigaset_driver *drv)
625 {
626 if (!drv->have_tty)
627 return;
628
629 drv->have_tty = 0;
630 tty_unregister_driver(drv->tty);
631 put_tty_driver(drv->tty);
632 }
633