xref: /openbmc/linux/sound/core/hwdep.c (revision 104326f8)
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/smp_lock.h>
26 #include <linux/slab.h>
27 #include <linux/time.h>
28 #include <linux/mutex.h>
29 #include <sound/core.h>
30 #include <sound/control.h>
31 #include <sound/minors.h>
32 #include <sound/hwdep.h>
33 #include <sound/info.h>
34 
35 MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
36 MODULE_DESCRIPTION("Hardware dependent layer");
37 MODULE_LICENSE("GPL");
38 
39 static LIST_HEAD(snd_hwdep_devices);
40 static DEFINE_MUTEX(register_mutex);
41 
42 static int snd_hwdep_free(struct snd_hwdep *hwdep);
43 static int snd_hwdep_dev_free(struct snd_device *device);
44 static int snd_hwdep_dev_register(struct snd_device *device);
45 static int snd_hwdep_dev_disconnect(struct snd_device *device);
46 
47 
48 static struct snd_hwdep *snd_hwdep_search(struct snd_card *card, int device)
49 {
50 	struct list_head *p;
51 	struct snd_hwdep *hwdep;
52 
53 	list_for_each(p, &snd_hwdep_devices) {
54 		hwdep = list_entry(p, struct snd_hwdep, list);
55 		if (hwdep->card == card && hwdep->device == device)
56 			return hwdep;
57 	}
58 	return NULL;
59 }
60 
61 static loff_t snd_hwdep_llseek(struct file * file, loff_t offset, int orig)
62 {
63 	struct snd_hwdep *hw = file->private_data;
64 	if (hw->ops.llseek)
65 		return hw->ops.llseek(hw, file, offset, orig);
66 	return -ENXIO;
67 }
68 
69 static ssize_t snd_hwdep_read(struct file * file, char __user *buf,
70 			      size_t count, loff_t *offset)
71 {
72 	struct snd_hwdep *hw = file->private_data;
73 	if (hw->ops.read)
74 		return hw->ops.read(hw, buf, count, offset);
75 	return -ENXIO;
76 }
77 
78 static ssize_t snd_hwdep_write(struct file * file, const char __user *buf,
79 			       size_t count, loff_t *offset)
80 {
81 	struct snd_hwdep *hw = file->private_data;
82 	if (hw->ops.write)
83 		return hw->ops.write(hw, buf, count, offset);
84 	return -ENXIO;
85 }
86 
87 static int snd_hwdep_open(struct inode *inode, struct file * file)
88 {
89 	int major = imajor(inode);
90 	struct snd_hwdep *hw;
91 	int err;
92 	wait_queue_t wait;
93 
94 	if (major == snd_major) {
95 		hw = snd_lookup_minor_data(iminor(inode),
96 					   SNDRV_DEVICE_TYPE_HWDEP);
97 #ifdef CONFIG_SND_OSSEMUL
98 	} else if (major == SOUND_MAJOR) {
99 		hw = snd_lookup_oss_minor_data(iminor(inode),
100 					       SNDRV_OSS_DEVICE_TYPE_DMFM);
101 #endif
102 	} else
103 		return -ENXIO;
104 	if (hw == NULL)
105 		return -ENODEV;
106 
107 	if (!hw->ops.open)
108 		return -ENXIO;
109 
110 	if (!try_module_get(hw->card->module))
111 		return -EFAULT;
112 
113 	init_waitqueue_entry(&wait, current);
114 	add_wait_queue(&hw->open_wait, &wait);
115 	mutex_lock(&hw->open_mutex);
116 	while (1) {
117 		if (hw->exclusive && hw->used > 0) {
118 			err = -EBUSY;
119 			break;
120 		}
121 		err = hw->ops.open(hw, file);
122 		if (err >= 0)
123 			break;
124 		if (err == -EAGAIN) {
125 			if (file->f_flags & O_NONBLOCK) {
126 				err = -EBUSY;
127 				break;
128 			}
129 		} else
130 			break;
131 		set_current_state(TASK_INTERRUPTIBLE);
132 		mutex_unlock(&hw->open_mutex);
133 		schedule();
134 		mutex_lock(&hw->open_mutex);
135 		if (signal_pending(current)) {
136 			err = -ERESTARTSYS;
137 			break;
138 		}
139 	}
140 	remove_wait_queue(&hw->open_wait, &wait);
141 	if (err >= 0) {
142 		err = snd_card_file_add(hw->card, file);
143 		if (err >= 0) {
144 			file->private_data = hw;
145 			hw->used++;
146 		} else {
147 			if (hw->ops.release)
148 				hw->ops.release(hw, file);
149 		}
150 	}
151 	mutex_unlock(&hw->open_mutex);
152 	if (err < 0)
153 		module_put(hw->card->module);
154 	return err;
155 }
156 
157 static int snd_hwdep_release(struct inode *inode, struct file * file)
158 {
159 	int err = -ENXIO;
160 	struct snd_hwdep *hw = file->private_data;
161 	struct module *mod = hw->card->module;
162 	mutex_lock(&hw->open_mutex);
163 	if (hw->ops.release) {
164 		err = hw->ops.release(hw, file);
165 		wake_up(&hw->open_wait);
166 	}
167 	if (hw->used > 0)
168 		hw->used--;
169 	snd_card_file_remove(hw->card, file);
170 	mutex_unlock(&hw->open_mutex);
171 	module_put(mod);
172 	return err;
173 }
174 
175 static unsigned int snd_hwdep_poll(struct file * file, poll_table * wait)
176 {
177 	struct snd_hwdep *hw = file->private_data;
178 	if (hw->ops.poll)
179 		return hw->ops.poll(hw, file, wait);
180 	return 0;
181 }
182 
183 static int snd_hwdep_info(struct snd_hwdep *hw,
184 			  struct snd_hwdep_info __user *_info)
185 {
186 	struct snd_hwdep_info info;
187 
188 	memset(&info, 0, sizeof(info));
189 	info.card = hw->card->number;
190 	strlcpy(info.id, hw->id, sizeof(info.id));
191 	strlcpy(info.name, hw->name, sizeof(info.name));
192 	info.iface = hw->iface;
193 	if (copy_to_user(_info, &info, sizeof(info)))
194 		return -EFAULT;
195 	return 0;
196 }
197 
198 static int snd_hwdep_dsp_status(struct snd_hwdep *hw,
199 				struct snd_hwdep_dsp_status __user *_info)
200 {
201 	struct snd_hwdep_dsp_status info;
202 	int err;
203 
204 	if (! hw->ops.dsp_status)
205 		return -ENXIO;
206 	memset(&info, 0, sizeof(info));
207 	info.dsp_loaded = hw->dsp_loaded;
208 	if ((err = hw->ops.dsp_status(hw, &info)) < 0)
209 		return err;
210 	if (copy_to_user(_info, &info, sizeof(info)))
211 		return -EFAULT;
212 	return 0;
213 }
214 
215 static int snd_hwdep_dsp_load(struct snd_hwdep *hw,
216 			      struct snd_hwdep_dsp_image __user *_info)
217 {
218 	struct snd_hwdep_dsp_image info;
219 	int err;
220 
221 	if (! hw->ops.dsp_load)
222 		return -ENXIO;
223 	memset(&info, 0, sizeof(info));
224 	if (copy_from_user(&info, _info, sizeof(info)))
225 		return -EFAULT;
226 	/* check whether the dsp was already loaded */
227 	if (hw->dsp_loaded & (1 << info.index))
228 		return -EBUSY;
229 	if (!access_ok(VERIFY_READ, info.image, info.length))
230 		return -EFAULT;
231 	err = hw->ops.dsp_load(hw, &info);
232 	if (err < 0)
233 		return err;
234 	hw->dsp_loaded |= (1 << info.index);
235 	return 0;
236 }
237 
238 static long snd_hwdep_ioctl(struct file * file, unsigned int cmd,
239 			    unsigned long arg)
240 {
241 	struct snd_hwdep *hw = file->private_data;
242 	void __user *argp = (void __user *)arg;
243 	switch (cmd) {
244 	case SNDRV_HWDEP_IOCTL_PVERSION:
245 		return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp);
246 	case SNDRV_HWDEP_IOCTL_INFO:
247 		return snd_hwdep_info(hw, argp);
248 	case SNDRV_HWDEP_IOCTL_DSP_STATUS:
249 		return snd_hwdep_dsp_status(hw, argp);
250 	case SNDRV_HWDEP_IOCTL_DSP_LOAD:
251 		return snd_hwdep_dsp_load(hw, argp);
252 	}
253 	if (hw->ops.ioctl)
254 		return hw->ops.ioctl(hw, file, cmd, arg);
255 	return -ENOTTY;
256 }
257 
258 static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma)
259 {
260 	struct snd_hwdep *hw = file->private_data;
261 	if (hw->ops.mmap)
262 		return hw->ops.mmap(hw, file, vma);
263 	return -ENXIO;
264 }
265 
266 static int snd_hwdep_control_ioctl(struct snd_card *card,
267 				   struct snd_ctl_file * control,
268 				   unsigned int cmd, unsigned long arg)
269 {
270 	switch (cmd) {
271 	case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE:
272 		{
273 			int device;
274 
275 			if (get_user(device, (int __user *)arg))
276 				return -EFAULT;
277 			mutex_lock(&register_mutex);
278 			device = device < 0 ? 0 : device + 1;
279 			while (device < SNDRV_MINOR_HWDEPS) {
280 				if (snd_hwdep_search(card, device))
281 					break;
282 				device++;
283 			}
284 			if (device >= SNDRV_MINOR_HWDEPS)
285 				device = -1;
286 			mutex_unlock(&register_mutex);
287 			if (put_user(device, (int __user *)arg))
288 				return -EFAULT;
289 			return 0;
290 		}
291 	case SNDRV_CTL_IOCTL_HWDEP_INFO:
292 		{
293 			struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg;
294 			int device, err;
295 			struct snd_hwdep *hwdep;
296 
297 			if (get_user(device, &info->device))
298 				return -EFAULT;
299 			mutex_lock(&register_mutex);
300 			hwdep = snd_hwdep_search(card, device);
301 			if (hwdep)
302 				err = snd_hwdep_info(hwdep, info);
303 			else
304 				err = -ENXIO;
305 			mutex_unlock(&register_mutex);
306 			return err;
307 		}
308 	}
309 	return -ENOIOCTLCMD;
310 }
311 
312 #ifdef CONFIG_COMPAT
313 #include "hwdep_compat.c"
314 #else
315 #define snd_hwdep_ioctl_compat	NULL
316 #endif
317 
318 /*
319 
320  */
321 
322 static struct file_operations snd_hwdep_f_ops =
323 {
324 	.owner = 	THIS_MODULE,
325 	.llseek =	snd_hwdep_llseek,
326 	.read = 	snd_hwdep_read,
327 	.write =	snd_hwdep_write,
328 	.open =		snd_hwdep_open,
329 	.release =	snd_hwdep_release,
330 	.poll =		snd_hwdep_poll,
331 	.unlocked_ioctl =	snd_hwdep_ioctl,
332 	.compat_ioctl =	snd_hwdep_ioctl_compat,
333 	.mmap =		snd_hwdep_mmap,
334 };
335 
336 /**
337  * snd_hwdep_new - create a new hwdep instance
338  * @card: the card instance
339  * @id: the id string
340  * @device: the device index (zero-based)
341  * @rhwdep: the pointer to store the new hwdep instance
342  *
343  * Creates a new hwdep instance with the given index on the card.
344  * The callbacks (hwdep->ops) must be set on the returned instance
345  * after this call manually by the caller.
346  *
347  * Returns zero if successful, or a negative error code on failure.
348  */
349 int snd_hwdep_new(struct snd_card *card, char *id, int device,
350 		  struct snd_hwdep **rhwdep)
351 {
352 	struct snd_hwdep *hwdep;
353 	int err;
354 	static struct snd_device_ops ops = {
355 		.dev_free = snd_hwdep_dev_free,
356 		.dev_register = snd_hwdep_dev_register,
357 		.dev_disconnect = snd_hwdep_dev_disconnect,
358 	};
359 
360 	snd_assert(rhwdep != NULL, return -EINVAL);
361 	*rhwdep = NULL;
362 	snd_assert(card != NULL, return -ENXIO);
363 	hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
364 	if (hwdep == NULL) {
365 		snd_printk(KERN_ERR "hwdep: cannot allocate\n");
366 		return -ENOMEM;
367 	}
368 	hwdep->card = card;
369 	hwdep->device = device;
370 	if (id)
371 		strlcpy(hwdep->id, id, sizeof(hwdep->id));
372 #ifdef CONFIG_SND_OSSEMUL
373 	hwdep->oss_type = -1;
374 #endif
375 	if ((err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops)) < 0) {
376 		snd_hwdep_free(hwdep);
377 		return err;
378 	}
379 	init_waitqueue_head(&hwdep->open_wait);
380 	mutex_init(&hwdep->open_mutex);
381 	*rhwdep = hwdep;
382 	return 0;
383 }
384 
385 static int snd_hwdep_free(struct snd_hwdep *hwdep)
386 {
387 	snd_assert(hwdep != NULL, return -ENXIO);
388 	if (hwdep->private_free)
389 		hwdep->private_free(hwdep);
390 	kfree(hwdep);
391 	return 0;
392 }
393 
394 static int snd_hwdep_dev_free(struct snd_device *device)
395 {
396 	struct snd_hwdep *hwdep = device->device_data;
397 	return snd_hwdep_free(hwdep);
398 }
399 
400 static int snd_hwdep_dev_register(struct snd_device *device)
401 {
402 	struct snd_hwdep *hwdep = device->device_data;
403 	int err;
404 	char name[32];
405 
406 	mutex_lock(&register_mutex);
407 	if (snd_hwdep_search(hwdep->card, hwdep->device)) {
408 		mutex_unlock(&register_mutex);
409 		return -EBUSY;
410 	}
411 	list_add_tail(&hwdep->list, &snd_hwdep_devices);
412 	sprintf(name, "hwC%iD%i", hwdep->card->number, hwdep->device);
413 	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
414 				       hwdep->card, hwdep->device,
415 				       &snd_hwdep_f_ops, hwdep, name)) < 0) {
416 		snd_printk(KERN_ERR "unable to register hardware dependent device %i:%i\n",
417 			   hwdep->card->number, hwdep->device);
418 		list_del(&hwdep->list);
419 		mutex_unlock(&register_mutex);
420 		return err;
421 	}
422 #ifdef CONFIG_SND_OSSEMUL
423 	hwdep->ossreg = 0;
424 	if (hwdep->oss_type >= 0) {
425 		if ((hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM) && (hwdep->device != 0)) {
426 			snd_printk (KERN_WARNING "only hwdep device 0 can be registered as OSS direct FM device!\n");
427 		} else {
428 			if (snd_register_oss_device(hwdep->oss_type,
429 						    hwdep->card, hwdep->device,
430 						    &snd_hwdep_f_ops, hwdep,
431 						    hwdep->oss_dev) < 0) {
432 				snd_printk(KERN_ERR "unable to register OSS compatibility device %i:%i\n",
433 					   hwdep->card->number, hwdep->device);
434 			} else
435 				hwdep->ossreg = 1;
436 		}
437 	}
438 #endif
439 	mutex_unlock(&register_mutex);
440 	return 0;
441 }
442 
443 static int snd_hwdep_dev_disconnect(struct snd_device *device)
444 {
445 	struct snd_hwdep *hwdep = device->device_data;
446 
447 	snd_assert(hwdep != NULL, return -ENXIO);
448 	mutex_lock(&register_mutex);
449 	if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) {
450 		mutex_unlock(&register_mutex);
451 		return -EINVAL;
452 	}
453 #ifdef CONFIG_SND_OSSEMUL
454 	if (hwdep->ossreg)
455 		snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
456 #endif
457 	snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
458 	list_del_init(&hwdep->list);
459 	mutex_unlock(&register_mutex);
460 	return 0;
461 }
462 
463 #ifdef CONFIG_PROC_FS
464 /*
465  *  Info interface
466  */
467 
468 static void snd_hwdep_proc_read(struct snd_info_entry *entry,
469 				struct snd_info_buffer *buffer)
470 {
471 	struct list_head *p;
472 	struct snd_hwdep *hwdep;
473 
474 	mutex_lock(&register_mutex);
475 	list_for_each(p, &snd_hwdep_devices) {
476 		hwdep = list_entry(p, struct snd_hwdep, list);
477 		snd_iprintf(buffer, "%02i-%02i: %s\n",
478 			    hwdep->card->number, hwdep->device, hwdep->name);
479 	}
480 	mutex_unlock(&register_mutex);
481 }
482 
483 static struct snd_info_entry *snd_hwdep_proc_entry;
484 
485 static void __init snd_hwdep_proc_init(void)
486 {
487 	struct snd_info_entry *entry;
488 
489 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
490 		entry->c.text.read = snd_hwdep_proc_read;
491 		if (snd_info_register(entry) < 0) {
492 			snd_info_free_entry(entry);
493 			entry = NULL;
494 		}
495 	}
496 	snd_hwdep_proc_entry = entry;
497 }
498 
499 static void __exit snd_hwdep_proc_done(void)
500 {
501 	snd_info_free_entry(snd_hwdep_proc_entry);
502 }
503 #else /* !CONFIG_PROC_FS */
504 #define snd_hwdep_proc_init()
505 #define snd_hwdep_proc_done()
506 #endif /* CONFIG_PROC_FS */
507 
508 
509 /*
510  *  ENTRY functions
511  */
512 
513 static int __init alsa_hwdep_init(void)
514 {
515 	snd_hwdep_proc_init();
516 	snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
517 	snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl);
518 	return 0;
519 }
520 
521 static void __exit alsa_hwdep_exit(void)
522 {
523 	snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
524 	snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl);
525 	snd_hwdep_proc_done();
526 }
527 
528 module_init(alsa_hwdep_init)
529 module_exit(alsa_hwdep_exit)
530 
531 EXPORT_SYMBOL(snd_hwdep_new);
532