xref: /openbmc/linux/sound/core/hwdep.c (revision 1eb4c977)
1 /*
2  *  Hardware dependent layer
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4  *
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *   GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program; if not, write to the Free Software
18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
19  *
20  */
21 
22 #include <linux/major.h>
23 #include <linux/init.h>
24 #include <linux/slab.h>
25 #include <linux/time.h>
26 #include <linux/mutex.h>
27 #include <linux/module.h>
28 #include <sound/core.h>
29 #include <sound/control.h>
30 #include <sound/minors.h>
31 #include <sound/hwdep.h>
32 #include <sound/info.h>
33 
34 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
35 MODULE_DESCRIPTION("Hardware dependent layer");
36 MODULE_LICENSE("GPL");
37 
38 static LIST_HEAD(snd_hwdep_devices);
39 static DEFINE_MUTEX(register_mutex);
40 
41 static int snd_hwdep_free(struct snd_hwdep *hwdep);
42 static int snd_hwdep_dev_free(struct snd_device *device);
43 static int snd_hwdep_dev_register(struct snd_device *device);
44 static int snd_hwdep_dev_disconnect(struct snd_device *device);
45 
46 
47 static struct snd_hwdep *snd_hwdep_search(struct snd_card *card, int device)
48 {
49 	struct snd_hwdep *hwdep;
50 
51 	list_for_each_entry(hwdep, &snd_hwdep_devices, list)
52 		if (hwdep->card == card && hwdep->device == device)
53 			return hwdep;
54 	return NULL;
55 }
56 
57 static loff_t snd_hwdep_llseek(struct file * file, loff_t offset, int orig)
58 {
59 	struct snd_hwdep *hw = file->private_data;
60 	if (hw->ops.llseek)
61 		return hw->ops.llseek(hw, file, offset, orig);
62 	return -ENXIO;
63 }
64 
65 static ssize_t snd_hwdep_read(struct file * file, char __user *buf,
66 			      size_t count, loff_t *offset)
67 {
68 	struct snd_hwdep *hw = file->private_data;
69 	if (hw->ops.read)
70 		return hw->ops.read(hw, buf, count, offset);
71 	return -ENXIO;
72 }
73 
74 static ssize_t snd_hwdep_write(struct file * file, const char __user *buf,
75 			       size_t count, loff_t *offset)
76 {
77 	struct snd_hwdep *hw = file->private_data;
78 	if (hw->ops.write)
79 		return hw->ops.write(hw, buf, count, offset);
80 	return -ENXIO;
81 }
82 
83 static int snd_hwdep_open(struct inode *inode, struct file * file)
84 {
85 	int major = imajor(inode);
86 	struct snd_hwdep *hw;
87 	int err;
88 	wait_queue_t wait;
89 
90 	if (major == snd_major) {
91 		hw = snd_lookup_minor_data(iminor(inode),
92 					   SNDRV_DEVICE_TYPE_HWDEP);
93 #ifdef CONFIG_SND_OSSEMUL
94 	} else if (major == SOUND_MAJOR) {
95 		hw = snd_lookup_oss_minor_data(iminor(inode),
96 					       SNDRV_OSS_DEVICE_TYPE_DMFM);
97 #endif
98 	} else
99 		return -ENXIO;
100 	if (hw == NULL)
101 		return -ENODEV;
102 
103 	if (!try_module_get(hw->card->module))
104 		return -EFAULT;
105 
106 	init_waitqueue_entry(&wait, current);
107 	add_wait_queue(&hw->open_wait, &wait);
108 	mutex_lock(&hw->open_mutex);
109 	while (1) {
110 		if (hw->exclusive && hw->used > 0) {
111 			err = -EBUSY;
112 			break;
113 		}
114 		if (!hw->ops.open) {
115 			err = 0;
116 			break;
117 		}
118 		err = hw->ops.open(hw, file);
119 		if (err >= 0)
120 			break;
121 		if (err == -EAGAIN) {
122 			if (file->f_flags & O_NONBLOCK) {
123 				err = -EBUSY;
124 				break;
125 			}
126 		} else
127 			break;
128 		set_current_state(TASK_INTERRUPTIBLE);
129 		mutex_unlock(&hw->open_mutex);
130 		schedule();
131 		mutex_lock(&hw->open_mutex);
132 		if (signal_pending(current)) {
133 			err = -ERESTARTSYS;
134 			break;
135 		}
136 	}
137 	remove_wait_queue(&hw->open_wait, &wait);
138 	if (err >= 0) {
139 		err = snd_card_file_add(hw->card, file);
140 		if (err >= 0) {
141 			file->private_data = hw;
142 			hw->used++;
143 		} else {
144 			if (hw->ops.release)
145 				hw->ops.release(hw, file);
146 		}
147 	}
148 	mutex_unlock(&hw->open_mutex);
149 	if (err < 0)
150 		module_put(hw->card->module);
151 	return err;
152 }
153 
154 static int snd_hwdep_release(struct inode *inode, struct file * file)
155 {
156 	int err = 0;
157 	struct snd_hwdep *hw = file->private_data;
158 	struct module *mod = hw->card->module;
159 
160 	mutex_lock(&hw->open_mutex);
161 	if (hw->ops.release)
162 		err = hw->ops.release(hw, file);
163 	if (hw->used > 0)
164 		hw->used--;
165 	mutex_unlock(&hw->open_mutex);
166 	wake_up(&hw->open_wait);
167 
168 	snd_card_file_remove(hw->card, file);
169 	module_put(mod);
170 	return err;
171 }
172 
173 static unsigned int snd_hwdep_poll(struct file * file, poll_table * wait)
174 {
175 	struct snd_hwdep *hw = file->private_data;
176 	if (hw->ops.poll)
177 		return hw->ops.poll(hw, file, wait);
178 	return 0;
179 }
180 
181 static int snd_hwdep_info(struct snd_hwdep *hw,
182 			  struct snd_hwdep_info __user *_info)
183 {
184 	struct snd_hwdep_info info;
185 
186 	memset(&info, 0, sizeof(info));
187 	info.card = hw->card->number;
188 	strlcpy(info.id, hw->id, sizeof(info.id));
189 	strlcpy(info.name, hw->name, sizeof(info.name));
190 	info.iface = hw->iface;
191 	if (copy_to_user(_info, &info, sizeof(info)))
192 		return -EFAULT;
193 	return 0;
194 }
195 
196 static int snd_hwdep_dsp_status(struct snd_hwdep *hw,
197 				struct snd_hwdep_dsp_status __user *_info)
198 {
199 	struct snd_hwdep_dsp_status info;
200 	int err;
201 
202 	if (! hw->ops.dsp_status)
203 		return -ENXIO;
204 	memset(&info, 0, sizeof(info));
205 	info.dsp_loaded = hw->dsp_loaded;
206 	if ((err = hw->ops.dsp_status(hw, &info)) < 0)
207 		return err;
208 	if (copy_to_user(_info, &info, sizeof(info)))
209 		return -EFAULT;
210 	return 0;
211 }
212 
213 static int snd_hwdep_dsp_load(struct snd_hwdep *hw,
214 			      struct snd_hwdep_dsp_image __user *_info)
215 {
216 	struct snd_hwdep_dsp_image info;
217 	int err;
218 
219 	if (! hw->ops.dsp_load)
220 		return -ENXIO;
221 	memset(&info, 0, sizeof(info));
222 	if (copy_from_user(&info, _info, sizeof(info)))
223 		return -EFAULT;
224 	/* check whether the dsp was already loaded */
225 	if (hw->dsp_loaded & (1 << info.index))
226 		return -EBUSY;
227 	if (!access_ok(VERIFY_READ, info.image, info.length))
228 		return -EFAULT;
229 	err = hw->ops.dsp_load(hw, &info);
230 	if (err < 0)
231 		return err;
232 	hw->dsp_loaded |= (1 << info.index);
233 	return 0;
234 }
235 
236 static long snd_hwdep_ioctl(struct file * file, unsigned int cmd,
237 			    unsigned long arg)
238 {
239 	struct snd_hwdep *hw = file->private_data;
240 	void __user *argp = (void __user *)arg;
241 	switch (cmd) {
242 	case SNDRV_HWDEP_IOCTL_PVERSION:
243 		return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp);
244 	case SNDRV_HWDEP_IOCTL_INFO:
245 		return snd_hwdep_info(hw, argp);
246 	case SNDRV_HWDEP_IOCTL_DSP_STATUS:
247 		return snd_hwdep_dsp_status(hw, argp);
248 	case SNDRV_HWDEP_IOCTL_DSP_LOAD:
249 		return snd_hwdep_dsp_load(hw, argp);
250 	}
251 	if (hw->ops.ioctl)
252 		return hw->ops.ioctl(hw, file, cmd, arg);
253 	return -ENOTTY;
254 }
255 
256 static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma)
257 {
258 	struct snd_hwdep *hw = file->private_data;
259 	if (hw->ops.mmap)
260 		return hw->ops.mmap(hw, file, vma);
261 	return -ENXIO;
262 }
263 
264 static int snd_hwdep_control_ioctl(struct snd_card *card,
265 				   struct snd_ctl_file * control,
266 				   unsigned int cmd, unsigned long arg)
267 {
268 	switch (cmd) {
269 	case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE:
270 		{
271 			int device;
272 
273 			if (get_user(device, (int __user *)arg))
274 				return -EFAULT;
275 			mutex_lock(&register_mutex);
276 
277 			if (device < 0)
278 				device = 0;
279 			else if (device < SNDRV_MINOR_HWDEPS)
280 				device++;
281 			else
282 				device = SNDRV_MINOR_HWDEPS;
283 
284 			while (device < SNDRV_MINOR_HWDEPS) {
285 				if (snd_hwdep_search(card, device))
286 					break;
287 				device++;
288 			}
289 			if (device >= SNDRV_MINOR_HWDEPS)
290 				device = -1;
291 			mutex_unlock(&register_mutex);
292 			if (put_user(device, (int __user *)arg))
293 				return -EFAULT;
294 			return 0;
295 		}
296 	case SNDRV_CTL_IOCTL_HWDEP_INFO:
297 		{
298 			struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg;
299 			int device, err;
300 			struct snd_hwdep *hwdep;
301 
302 			if (get_user(device, &info->device))
303 				return -EFAULT;
304 			mutex_lock(&register_mutex);
305 			hwdep = snd_hwdep_search(card, device);
306 			if (hwdep)
307 				err = snd_hwdep_info(hwdep, info);
308 			else
309 				err = -ENXIO;
310 			mutex_unlock(&register_mutex);
311 			return err;
312 		}
313 	}
314 	return -ENOIOCTLCMD;
315 }
316 
317 #ifdef CONFIG_COMPAT
318 #include "hwdep_compat.c"
319 #else
320 #define snd_hwdep_ioctl_compat	NULL
321 #endif
322 
323 /*
324 
325  */
326 
327 static const struct file_operations snd_hwdep_f_ops =
328 {
329 	.owner = 	THIS_MODULE,
330 	.llseek =	snd_hwdep_llseek,
331 	.read = 	snd_hwdep_read,
332 	.write =	snd_hwdep_write,
333 	.open =		snd_hwdep_open,
334 	.release =	snd_hwdep_release,
335 	.poll =		snd_hwdep_poll,
336 	.unlocked_ioctl =	snd_hwdep_ioctl,
337 	.compat_ioctl =	snd_hwdep_ioctl_compat,
338 	.mmap =		snd_hwdep_mmap,
339 };
340 
341 /**
342  * snd_hwdep_new - create a new hwdep instance
343  * @card: the card instance
344  * @id: the id string
345  * @device: the device index (zero-based)
346  * @rhwdep: the pointer to store the new hwdep instance
347  *
348  * Creates a new hwdep instance with the given index on the card.
349  * The callbacks (hwdep->ops) must be set on the returned instance
350  * after this call manually by the caller.
351  *
352  * Returns zero if successful, or a negative error code on failure.
353  */
354 int snd_hwdep_new(struct snd_card *card, char *id, int device,
355 		  struct snd_hwdep **rhwdep)
356 {
357 	struct snd_hwdep *hwdep;
358 	int err;
359 	static struct snd_device_ops ops = {
360 		.dev_free = snd_hwdep_dev_free,
361 		.dev_register = snd_hwdep_dev_register,
362 		.dev_disconnect = snd_hwdep_dev_disconnect,
363 	};
364 
365 	if (snd_BUG_ON(!card))
366 		return -ENXIO;
367 	if (rhwdep)
368 		*rhwdep = NULL;
369 	hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
370 	if (hwdep == NULL) {
371 		snd_printk(KERN_ERR "hwdep: cannot allocate\n");
372 		return -ENOMEM;
373 	}
374 	hwdep->card = card;
375 	hwdep->device = device;
376 	if (id)
377 		strlcpy(hwdep->id, id, sizeof(hwdep->id));
378 #ifdef CONFIG_SND_OSSEMUL
379 	hwdep->oss_type = -1;
380 #endif
381 	if ((err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops)) < 0) {
382 		snd_hwdep_free(hwdep);
383 		return err;
384 	}
385 	init_waitqueue_head(&hwdep->open_wait);
386 	mutex_init(&hwdep->open_mutex);
387 	if (rhwdep)
388 		*rhwdep = hwdep;
389 	return 0;
390 }
391 
392 static int snd_hwdep_free(struct snd_hwdep *hwdep)
393 {
394 	if (!hwdep)
395 		return 0;
396 	if (hwdep->private_free)
397 		hwdep->private_free(hwdep);
398 	kfree(hwdep);
399 	return 0;
400 }
401 
402 static int snd_hwdep_dev_free(struct snd_device *device)
403 {
404 	struct snd_hwdep *hwdep = device->device_data;
405 	return snd_hwdep_free(hwdep);
406 }
407 
408 static int snd_hwdep_dev_register(struct snd_device *device)
409 {
410 	struct snd_hwdep *hwdep = device->device_data;
411 	int err;
412 	char name[32];
413 
414 	mutex_lock(&register_mutex);
415 	if (snd_hwdep_search(hwdep->card, hwdep->device)) {
416 		mutex_unlock(&register_mutex);
417 		return -EBUSY;
418 	}
419 	list_add_tail(&hwdep->list, &snd_hwdep_devices);
420 	sprintf(name, "hwC%iD%i", hwdep->card->number, hwdep->device);
421 	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
422 				       hwdep->card, hwdep->device,
423 				       &snd_hwdep_f_ops, hwdep, name)) < 0) {
424 		snd_printk(KERN_ERR "unable to register hardware dependent device %i:%i\n",
425 			   hwdep->card->number, hwdep->device);
426 		list_del(&hwdep->list);
427 		mutex_unlock(&register_mutex);
428 		return err;
429 	}
430 #ifdef CONFIG_SND_OSSEMUL
431 	hwdep->ossreg = 0;
432 	if (hwdep->oss_type >= 0) {
433 		if ((hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM) && (hwdep->device != 0)) {
434 			snd_printk (KERN_WARNING "only hwdep device 0 can be registered as OSS direct FM device!\n");
435 		} else {
436 			if (snd_register_oss_device(hwdep->oss_type,
437 						    hwdep->card, hwdep->device,
438 						    &snd_hwdep_f_ops, hwdep,
439 						    hwdep->oss_dev) < 0) {
440 				snd_printk(KERN_ERR "unable to register OSS compatibility device %i:%i\n",
441 					   hwdep->card->number, hwdep->device);
442 			} else
443 				hwdep->ossreg = 1;
444 		}
445 	}
446 #endif
447 	mutex_unlock(&register_mutex);
448 	return 0;
449 }
450 
451 static int snd_hwdep_dev_disconnect(struct snd_device *device)
452 {
453 	struct snd_hwdep *hwdep = device->device_data;
454 
455 	if (snd_BUG_ON(!hwdep))
456 		return -ENXIO;
457 	mutex_lock(&register_mutex);
458 	if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) {
459 		mutex_unlock(&register_mutex);
460 		return -EINVAL;
461 	}
462 #ifdef CONFIG_SND_OSSEMUL
463 	if (hwdep->ossreg)
464 		snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
465 #endif
466 	snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
467 	list_del_init(&hwdep->list);
468 	mutex_unlock(&register_mutex);
469 	return 0;
470 }
471 
472 #ifdef CONFIG_PROC_FS
473 /*
474  *  Info interface
475  */
476 
477 static void snd_hwdep_proc_read(struct snd_info_entry *entry,
478 				struct snd_info_buffer *buffer)
479 {
480 	struct snd_hwdep *hwdep;
481 
482 	mutex_lock(&register_mutex);
483 	list_for_each_entry(hwdep, &snd_hwdep_devices, list)
484 		snd_iprintf(buffer, "%02i-%02i: %s\n",
485 			    hwdep->card->number, hwdep->device, hwdep->name);
486 	mutex_unlock(&register_mutex);
487 }
488 
489 static struct snd_info_entry *snd_hwdep_proc_entry;
490 
491 static void __init snd_hwdep_proc_init(void)
492 {
493 	struct snd_info_entry *entry;
494 
495 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
496 		entry->c.text.read = snd_hwdep_proc_read;
497 		if (snd_info_register(entry) < 0) {
498 			snd_info_free_entry(entry);
499 			entry = NULL;
500 		}
501 	}
502 	snd_hwdep_proc_entry = entry;
503 }
504 
505 static void __exit snd_hwdep_proc_done(void)
506 {
507 	snd_info_free_entry(snd_hwdep_proc_entry);
508 }
509 #else /* !CONFIG_PROC_FS */
510 #define snd_hwdep_proc_init()
511 #define snd_hwdep_proc_done()
512 #endif /* CONFIG_PROC_FS */
513 
514 
515 /*
516  *  ENTRY functions
517  */
518 
519 static int __init alsa_hwdep_init(void)
520 {
521 	snd_hwdep_proc_init();
522 	snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
523 	snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl);
524 	return 0;
525 }
526 
527 static void __exit alsa_hwdep_exit(void)
528 {
529 	snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
530 	snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl);
531 	snd_hwdep_proc_done();
532 }
533 
534 module_init(alsa_hwdep_init)
535 module_exit(alsa_hwdep_exit)
536 
537 EXPORT_SYMBOL(snd_hwdep_new);
538