xref: /openbmc/linux/sound/core/hwdep.c (revision 64c70b1c)
1 /*
2  *  Hardware dependent layer
3  *  Copyright (c) by Jaroslav Kysela <perex@suse.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 <sound/driver.h>
23 #include <linux/major.h>
24 #include <linux/init.h>
25 #include <linux/slab.h>
26 #include <linux/time.h>
27 #include <linux/mutex.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@suse.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 (!hw->ops.open)
104 		return -ENXIO;
105 
106 	if (!try_module_get(hw->card->module))
107 		return -EFAULT;
108 
109 	init_waitqueue_entry(&wait, current);
110 	add_wait_queue(&hw->open_wait, &wait);
111 	mutex_lock(&hw->open_mutex);
112 	while (1) {
113 		if (hw->exclusive && hw->used > 0) {
114 			err = -EBUSY;
115 			break;
116 		}
117 		err = hw->ops.open(hw, file);
118 		if (err >= 0)
119 			break;
120 		if (err == -EAGAIN) {
121 			if (file->f_flags & O_NONBLOCK) {
122 				err = -EBUSY;
123 				break;
124 			}
125 		} else
126 			break;
127 		set_current_state(TASK_INTERRUPTIBLE);
128 		mutex_unlock(&hw->open_mutex);
129 		schedule();
130 		mutex_lock(&hw->open_mutex);
131 		if (signal_pending(current)) {
132 			err = -ERESTARTSYS;
133 			break;
134 		}
135 	}
136 	remove_wait_queue(&hw->open_wait, &wait);
137 	if (err >= 0) {
138 		err = snd_card_file_add(hw->card, file);
139 		if (err >= 0) {
140 			file->private_data = hw;
141 			hw->used++;
142 		} else {
143 			if (hw->ops.release)
144 				hw->ops.release(hw, file);
145 		}
146 	}
147 	mutex_unlock(&hw->open_mutex);
148 	if (err < 0)
149 		module_put(hw->card->module);
150 	return err;
151 }
152 
153 static int snd_hwdep_release(struct inode *inode, struct file * file)
154 {
155 	int err = -ENXIO;
156 	struct snd_hwdep *hw = file->private_data;
157 	struct module *mod = hw->card->module;
158 
159 	mutex_lock(&hw->open_mutex);
160 	if (hw->ops.release)
161 		err = hw->ops.release(hw, file);
162 	if (hw->used > 0)
163 		hw->used--;
164 	mutex_unlock(&hw->open_mutex);
165 	wake_up(&hw->open_wait);
166 
167 	snd_card_file_remove(hw->card, file);
168 	module_put(mod);
169 	return err;
170 }
171 
172 static unsigned int snd_hwdep_poll(struct file * file, poll_table * wait)
173 {
174 	struct snd_hwdep *hw = file->private_data;
175 	if (hw->ops.poll)
176 		return hw->ops.poll(hw, file, wait);
177 	return 0;
178 }
179 
180 static int snd_hwdep_info(struct snd_hwdep *hw,
181 			  struct snd_hwdep_info __user *_info)
182 {
183 	struct snd_hwdep_info info;
184 
185 	memset(&info, 0, sizeof(info));
186 	info.card = hw->card->number;
187 	strlcpy(info.id, hw->id, sizeof(info.id));
188 	strlcpy(info.name, hw->name, sizeof(info.name));
189 	info.iface = hw->iface;
190 	if (copy_to_user(_info, &info, sizeof(info)))
191 		return -EFAULT;
192 	return 0;
193 }
194 
195 static int snd_hwdep_dsp_status(struct snd_hwdep *hw,
196 				struct snd_hwdep_dsp_status __user *_info)
197 {
198 	struct snd_hwdep_dsp_status info;
199 	int err;
200 
201 	if (! hw->ops.dsp_status)
202 		return -ENXIO;
203 	memset(&info, 0, sizeof(info));
204 	info.dsp_loaded = hw->dsp_loaded;
205 	if ((err = hw->ops.dsp_status(hw, &info)) < 0)
206 		return err;
207 	if (copy_to_user(_info, &info, sizeof(info)))
208 		return -EFAULT;
209 	return 0;
210 }
211 
212 static int snd_hwdep_dsp_load(struct snd_hwdep *hw,
213 			      struct snd_hwdep_dsp_image __user *_info)
214 {
215 	struct snd_hwdep_dsp_image info;
216 	int err;
217 
218 	if (! hw->ops.dsp_load)
219 		return -ENXIO;
220 	memset(&info, 0, sizeof(info));
221 	if (copy_from_user(&info, _info, sizeof(info)))
222 		return -EFAULT;
223 	/* check whether the dsp was already loaded */
224 	if (hw->dsp_loaded & (1 << info.index))
225 		return -EBUSY;
226 	if (!access_ok(VERIFY_READ, info.image, info.length))
227 		return -EFAULT;
228 	err = hw->ops.dsp_load(hw, &info);
229 	if (err < 0)
230 		return err;
231 	hw->dsp_loaded |= (1 << info.index);
232 	return 0;
233 }
234 
235 static long snd_hwdep_ioctl(struct file * file, unsigned int cmd,
236 			    unsigned long arg)
237 {
238 	struct snd_hwdep *hw = file->private_data;
239 	void __user *argp = (void __user *)arg;
240 	switch (cmd) {
241 	case SNDRV_HWDEP_IOCTL_PVERSION:
242 		return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp);
243 	case SNDRV_HWDEP_IOCTL_INFO:
244 		return snd_hwdep_info(hw, argp);
245 	case SNDRV_HWDEP_IOCTL_DSP_STATUS:
246 		return snd_hwdep_dsp_status(hw, argp);
247 	case SNDRV_HWDEP_IOCTL_DSP_LOAD:
248 		return snd_hwdep_dsp_load(hw, argp);
249 	}
250 	if (hw->ops.ioctl)
251 		return hw->ops.ioctl(hw, file, cmd, arg);
252 	return -ENOTTY;
253 }
254 
255 static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma)
256 {
257 	struct snd_hwdep *hw = file->private_data;
258 	if (hw->ops.mmap)
259 		return hw->ops.mmap(hw, file, vma);
260 	return -ENXIO;
261 }
262 
263 static int snd_hwdep_control_ioctl(struct snd_card *card,
264 				   struct snd_ctl_file * control,
265 				   unsigned int cmd, unsigned long arg)
266 {
267 	switch (cmd) {
268 	case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE:
269 		{
270 			int device;
271 
272 			if (get_user(device, (int __user *)arg))
273 				return -EFAULT;
274 			mutex_lock(&register_mutex);
275 			device = device < 0 ? 0 : device + 1;
276 			while (device < SNDRV_MINOR_HWDEPS) {
277 				if (snd_hwdep_search(card, device))
278 					break;
279 				device++;
280 			}
281 			if (device >= SNDRV_MINOR_HWDEPS)
282 				device = -1;
283 			mutex_unlock(&register_mutex);
284 			if (put_user(device, (int __user *)arg))
285 				return -EFAULT;
286 			return 0;
287 		}
288 	case SNDRV_CTL_IOCTL_HWDEP_INFO:
289 		{
290 			struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg;
291 			int device, err;
292 			struct snd_hwdep *hwdep;
293 
294 			if (get_user(device, &info->device))
295 				return -EFAULT;
296 			mutex_lock(&register_mutex);
297 			hwdep = snd_hwdep_search(card, device);
298 			if (hwdep)
299 				err = snd_hwdep_info(hwdep, info);
300 			else
301 				err = -ENXIO;
302 			mutex_unlock(&register_mutex);
303 			return err;
304 		}
305 	}
306 	return -ENOIOCTLCMD;
307 }
308 
309 #ifdef CONFIG_COMPAT
310 #include "hwdep_compat.c"
311 #else
312 #define snd_hwdep_ioctl_compat	NULL
313 #endif
314 
315 /*
316 
317  */
318 
319 static const struct file_operations snd_hwdep_f_ops =
320 {
321 	.owner = 	THIS_MODULE,
322 	.llseek =	snd_hwdep_llseek,
323 	.read = 	snd_hwdep_read,
324 	.write =	snd_hwdep_write,
325 	.open =		snd_hwdep_open,
326 	.release =	snd_hwdep_release,
327 	.poll =		snd_hwdep_poll,
328 	.unlocked_ioctl =	snd_hwdep_ioctl,
329 	.compat_ioctl =	snd_hwdep_ioctl_compat,
330 	.mmap =		snd_hwdep_mmap,
331 };
332 
333 /**
334  * snd_hwdep_new - create a new hwdep instance
335  * @card: the card instance
336  * @id: the id string
337  * @device: the device index (zero-based)
338  * @rhwdep: the pointer to store the new hwdep instance
339  *
340  * Creates a new hwdep instance with the given index on the card.
341  * The callbacks (hwdep->ops) must be set on the returned instance
342  * after this call manually by the caller.
343  *
344  * Returns zero if successful, or a negative error code on failure.
345  */
346 int snd_hwdep_new(struct snd_card *card, char *id, int device,
347 		  struct snd_hwdep **rhwdep)
348 {
349 	struct snd_hwdep *hwdep;
350 	int err;
351 	static struct snd_device_ops ops = {
352 		.dev_free = snd_hwdep_dev_free,
353 		.dev_register = snd_hwdep_dev_register,
354 		.dev_disconnect = snd_hwdep_dev_disconnect,
355 	};
356 
357 	snd_assert(rhwdep != NULL, return -EINVAL);
358 	*rhwdep = NULL;
359 	snd_assert(card != NULL, return -ENXIO);
360 	hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
361 	if (hwdep == NULL) {
362 		snd_printk(KERN_ERR "hwdep: cannot allocate\n");
363 		return -ENOMEM;
364 	}
365 	hwdep->card = card;
366 	hwdep->device = device;
367 	if (id)
368 		strlcpy(hwdep->id, id, sizeof(hwdep->id));
369 #ifdef CONFIG_SND_OSSEMUL
370 	hwdep->oss_type = -1;
371 #endif
372 	if ((err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops)) < 0) {
373 		snd_hwdep_free(hwdep);
374 		return err;
375 	}
376 	init_waitqueue_head(&hwdep->open_wait);
377 	mutex_init(&hwdep->open_mutex);
378 	*rhwdep = hwdep;
379 	return 0;
380 }
381 
382 static int snd_hwdep_free(struct snd_hwdep *hwdep)
383 {
384 	snd_assert(hwdep != NULL, return -ENXIO);
385 	if (hwdep->private_free)
386 		hwdep->private_free(hwdep);
387 	kfree(hwdep);
388 	return 0;
389 }
390 
391 static int snd_hwdep_dev_free(struct snd_device *device)
392 {
393 	struct snd_hwdep *hwdep = device->device_data;
394 	return snd_hwdep_free(hwdep);
395 }
396 
397 static int snd_hwdep_dev_register(struct snd_device *device)
398 {
399 	struct snd_hwdep *hwdep = device->device_data;
400 	int err;
401 	char name[32];
402 
403 	mutex_lock(&register_mutex);
404 	if (snd_hwdep_search(hwdep->card, hwdep->device)) {
405 		mutex_unlock(&register_mutex);
406 		return -EBUSY;
407 	}
408 	list_add_tail(&hwdep->list, &snd_hwdep_devices);
409 	sprintf(name, "hwC%iD%i", hwdep->card->number, hwdep->device);
410 	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
411 				       hwdep->card, hwdep->device,
412 				       &snd_hwdep_f_ops, hwdep, name)) < 0) {
413 		snd_printk(KERN_ERR "unable to register hardware dependent device %i:%i\n",
414 			   hwdep->card->number, hwdep->device);
415 		list_del(&hwdep->list);
416 		mutex_unlock(&register_mutex);
417 		return err;
418 	}
419 #ifdef CONFIG_SND_OSSEMUL
420 	hwdep->ossreg = 0;
421 	if (hwdep->oss_type >= 0) {
422 		if ((hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM) && (hwdep->device != 0)) {
423 			snd_printk (KERN_WARNING "only hwdep device 0 can be registered as OSS direct FM device!\n");
424 		} else {
425 			if (snd_register_oss_device(hwdep->oss_type,
426 						    hwdep->card, hwdep->device,
427 						    &snd_hwdep_f_ops, hwdep,
428 						    hwdep->oss_dev) < 0) {
429 				snd_printk(KERN_ERR "unable to register OSS compatibility device %i:%i\n",
430 					   hwdep->card->number, hwdep->device);
431 			} else
432 				hwdep->ossreg = 1;
433 		}
434 	}
435 #endif
436 	mutex_unlock(&register_mutex);
437 	return 0;
438 }
439 
440 static int snd_hwdep_dev_disconnect(struct snd_device *device)
441 {
442 	struct snd_hwdep *hwdep = device->device_data;
443 
444 	snd_assert(hwdep != NULL, return -ENXIO);
445 	mutex_lock(&register_mutex);
446 	if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) {
447 		mutex_unlock(&register_mutex);
448 		return -EINVAL;
449 	}
450 #ifdef CONFIG_SND_OSSEMUL
451 	if (hwdep->ossreg)
452 		snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
453 #endif
454 	snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
455 	list_del_init(&hwdep->list);
456 	mutex_unlock(&register_mutex);
457 	return 0;
458 }
459 
460 #ifdef CONFIG_PROC_FS
461 /*
462  *  Info interface
463  */
464 
465 static void snd_hwdep_proc_read(struct snd_info_entry *entry,
466 				struct snd_info_buffer *buffer)
467 {
468 	struct snd_hwdep *hwdep;
469 
470 	mutex_lock(&register_mutex);
471 	list_for_each_entry(hwdep, &snd_hwdep_devices, list)
472 		snd_iprintf(buffer, "%02i-%02i: %s\n",
473 			    hwdep->card->number, hwdep->device, hwdep->name);
474 	mutex_unlock(&register_mutex);
475 }
476 
477 static struct snd_info_entry *snd_hwdep_proc_entry;
478 
479 static void __init snd_hwdep_proc_init(void)
480 {
481 	struct snd_info_entry *entry;
482 
483 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
484 		entry->c.text.read = snd_hwdep_proc_read;
485 		if (snd_info_register(entry) < 0) {
486 			snd_info_free_entry(entry);
487 			entry = NULL;
488 		}
489 	}
490 	snd_hwdep_proc_entry = entry;
491 }
492 
493 static void __exit snd_hwdep_proc_done(void)
494 {
495 	snd_info_free_entry(snd_hwdep_proc_entry);
496 }
497 #else /* !CONFIG_PROC_FS */
498 #define snd_hwdep_proc_init()
499 #define snd_hwdep_proc_done()
500 #endif /* CONFIG_PROC_FS */
501 
502 
503 /*
504  *  ENTRY functions
505  */
506 
507 static int __init alsa_hwdep_init(void)
508 {
509 	snd_hwdep_proc_init();
510 	snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
511 	snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl);
512 	return 0;
513 }
514 
515 static void __exit alsa_hwdep_exit(void)
516 {
517 	snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
518 	snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl);
519 	snd_hwdep_proc_done();
520 }
521 
522 module_init(alsa_hwdep_init)
523 module_exit(alsa_hwdep_exit)
524 
525 EXPORT_SYMBOL(snd_hwdep_new);
526