xref: /openbmc/linux/sound/core/hwdep.c (revision 345d0b19)
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 <sound/core.h>
28 #include <sound/control.h>
29 #include <sound/minors.h>
30 #include <sound/hwdep.h>
31 #include <sound/info.h>
32 
33 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
34 MODULE_DESCRIPTION("Hardware dependent layer");
35 MODULE_LICENSE("GPL");
36 
37 static LIST_HEAD(snd_hwdep_devices);
38 static DEFINE_MUTEX(register_mutex);
39 
40 static int snd_hwdep_free(struct snd_hwdep *hwdep);
41 static int snd_hwdep_dev_free(struct snd_device *device);
42 static int snd_hwdep_dev_register(struct snd_device *device);
43 static int snd_hwdep_dev_disconnect(struct snd_device *device);
44 
45 
46 static struct snd_hwdep *snd_hwdep_search(struct snd_card *card, int device)
47 {
48 	struct snd_hwdep *hwdep;
49 
50 	list_for_each_entry(hwdep, &snd_hwdep_devices, list)
51 		if (hwdep->card == card && hwdep->device == device)
52 			return hwdep;
53 	return NULL;
54 }
55 
56 static loff_t snd_hwdep_llseek(struct file * file, loff_t offset, int orig)
57 {
58 	struct snd_hwdep *hw = file->private_data;
59 	if (hw->ops.llseek)
60 		return hw->ops.llseek(hw, file, offset, orig);
61 	return -ENXIO;
62 }
63 
64 static ssize_t snd_hwdep_read(struct file * file, char __user *buf,
65 			      size_t count, loff_t *offset)
66 {
67 	struct snd_hwdep *hw = file->private_data;
68 	if (hw->ops.read)
69 		return hw->ops.read(hw, buf, count, offset);
70 	return -ENXIO;
71 }
72 
73 static ssize_t snd_hwdep_write(struct file * file, const char __user *buf,
74 			       size_t count, loff_t *offset)
75 {
76 	struct snd_hwdep *hw = file->private_data;
77 	if (hw->ops.write)
78 		return hw->ops.write(hw, buf, count, offset);
79 	return -ENXIO;
80 }
81 
82 static int snd_hwdep_open(struct inode *inode, struct file * file)
83 {
84 	int major = imajor(inode);
85 	struct snd_hwdep *hw;
86 	int err;
87 	wait_queue_t wait;
88 
89 	if (major == snd_major) {
90 		hw = snd_lookup_minor_data(iminor(inode),
91 					   SNDRV_DEVICE_TYPE_HWDEP);
92 #ifdef CONFIG_SND_OSSEMUL
93 	} else if (major == SOUND_MAJOR) {
94 		hw = snd_lookup_oss_minor_data(iminor(inode),
95 					       SNDRV_OSS_DEVICE_TYPE_DMFM);
96 #endif
97 	} else
98 		return -ENXIO;
99 	if (hw == NULL)
100 		return -ENODEV;
101 
102 	if (!try_module_get(hw->card->module))
103 		return -EFAULT;
104 
105 	init_waitqueue_entry(&wait, current);
106 	add_wait_queue(&hw->open_wait, &wait);
107 	mutex_lock(&hw->open_mutex);
108 	while (1) {
109 		if (hw->exclusive && hw->used > 0) {
110 			err = -EBUSY;
111 			break;
112 		}
113 		if (!hw->ops.open) {
114 			err = 0;
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 = 0;
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 	if (snd_BUG_ON(!card))
358 		return -ENXIO;
359 	if (rhwdep)
360 		*rhwdep = NULL;
361 	hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
362 	if (hwdep == NULL) {
363 		snd_printk(KERN_ERR "hwdep: cannot allocate\n");
364 		return -ENOMEM;
365 	}
366 	hwdep->card = card;
367 	hwdep->device = device;
368 	if (id)
369 		strlcpy(hwdep->id, id, sizeof(hwdep->id));
370 #ifdef CONFIG_SND_OSSEMUL
371 	hwdep->oss_type = -1;
372 #endif
373 	if ((err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops)) < 0) {
374 		snd_hwdep_free(hwdep);
375 		return err;
376 	}
377 	init_waitqueue_head(&hwdep->open_wait);
378 	mutex_init(&hwdep->open_mutex);
379 	if (rhwdep)
380 		*rhwdep = hwdep;
381 	return 0;
382 }
383 
384 static int snd_hwdep_free(struct snd_hwdep *hwdep)
385 {
386 	if (!hwdep)
387 		return 0;
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 	if (snd_BUG_ON(!hwdep))
448 		return -ENXIO;
449 	mutex_lock(&register_mutex);
450 	if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) {
451 		mutex_unlock(&register_mutex);
452 		return -EINVAL;
453 	}
454 #ifdef CONFIG_SND_OSSEMUL
455 	if (hwdep->ossreg)
456 		snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
457 #endif
458 	snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
459 	list_del_init(&hwdep->list);
460 	mutex_unlock(&register_mutex);
461 	return 0;
462 }
463 
464 #ifdef CONFIG_PROC_FS
465 /*
466  *  Info interface
467  */
468 
469 static void snd_hwdep_proc_read(struct snd_info_entry *entry,
470 				struct snd_info_buffer *buffer)
471 {
472 	struct snd_hwdep *hwdep;
473 
474 	mutex_lock(&register_mutex);
475 	list_for_each_entry(hwdep, &snd_hwdep_devices, list)
476 		snd_iprintf(buffer, "%02i-%02i: %s\n",
477 			    hwdep->card->number, hwdep->device, hwdep->name);
478 	mutex_unlock(&register_mutex);
479 }
480 
481 static struct snd_info_entry *snd_hwdep_proc_entry;
482 
483 static void __init snd_hwdep_proc_init(void)
484 {
485 	struct snd_info_entry *entry;
486 
487 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
488 		entry->c.text.read = snd_hwdep_proc_read;
489 		if (snd_info_register(entry) < 0) {
490 			snd_info_free_entry(entry);
491 			entry = NULL;
492 		}
493 	}
494 	snd_hwdep_proc_entry = entry;
495 }
496 
497 static void __exit snd_hwdep_proc_done(void)
498 {
499 	snd_info_free_entry(snd_hwdep_proc_entry);
500 }
501 #else /* !CONFIG_PROC_FS */
502 #define snd_hwdep_proc_init()
503 #define snd_hwdep_proc_done()
504 #endif /* CONFIG_PROC_FS */
505 
506 
507 /*
508  *  ENTRY functions
509  */
510 
511 static int __init alsa_hwdep_init(void)
512 {
513 	snd_hwdep_proc_init();
514 	snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
515 	snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl);
516 	return 0;
517 }
518 
519 static void __exit alsa_hwdep_exit(void)
520 {
521 	snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
522 	snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl);
523 	snd_hwdep_proc_done();
524 }
525 
526 module_init(alsa_hwdep_init)
527 module_exit(alsa_hwdep_exit)
528 
529 EXPORT_SYMBOL(snd_hwdep_new);
530