xref: /linux/sound/core/hwdep.c (revision 9ce7677cfd7cd871adb457c80bea3b581b839641)
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 <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 snd_hwdep_t *snd_hwdep_devices[SNDRV_CARDS * SNDRV_MINOR_HWDEPS];
39 
40 static DECLARE_MUTEX(register_mutex);
41 
42 static int snd_hwdep_free(snd_hwdep_t *hwdep);
43 static int snd_hwdep_dev_free(snd_device_t *device);
44 static int snd_hwdep_dev_register(snd_device_t *device);
45 static int snd_hwdep_dev_unregister(snd_device_t *device);
46 
47 /*
48 
49  */
50 
51 static loff_t snd_hwdep_llseek(struct file * file, loff_t offset, int orig)
52 {
53 	snd_hwdep_t *hw = file->private_data;
54 	if (hw->ops.llseek)
55 		return hw->ops.llseek(hw, file, offset, orig);
56 	return -ENXIO;
57 }
58 
59 static ssize_t snd_hwdep_read(struct file * file, char __user *buf, size_t count, loff_t *offset)
60 {
61 	snd_hwdep_t *hw = file->private_data;
62 	if (hw->ops.read)
63 		return hw->ops.read(hw, buf, count, offset);
64 	return -ENXIO;
65 }
66 
67 static ssize_t snd_hwdep_write(struct file * file, const char __user *buf, size_t count, loff_t *offset)
68 {
69 	snd_hwdep_t *hw = file->private_data;
70 	if (hw->ops.write)
71 		return hw->ops.write(hw, buf, count, offset);
72 	return -ENXIO;
73 }
74 
75 static int snd_hwdep_open(struct inode *inode, struct file * file)
76 {
77 	int major = imajor(inode);
78 	int cardnum;
79 	int device;
80 	snd_hwdep_t *hw;
81 	int err;
82 	wait_queue_t wait;
83 
84 	if (major == snd_major) {
85 		cardnum = SNDRV_MINOR_CARD(iminor(inode));
86 		device = SNDRV_MINOR_DEVICE(iminor(inode)) - SNDRV_MINOR_HWDEP;
87 #ifdef CONFIG_SND_OSSEMUL
88 	} else if (major == SOUND_MAJOR) {
89 		cardnum = SNDRV_MINOR_OSS_CARD(iminor(inode));
90 		device = 0;
91 #endif
92 	} else
93 		return -ENXIO;
94 	cardnum %= SNDRV_CARDS;
95 	device %= SNDRV_MINOR_HWDEPS;
96 	hw = snd_hwdep_devices[(cardnum * SNDRV_MINOR_HWDEPS) + device];
97 	if (hw == NULL)
98 		return -ENODEV;
99 
100 	if (!hw->ops.open)
101 		return -ENXIO;
102 #ifdef CONFIG_SND_OSSEMUL
103 	if (major == SOUND_MAJOR && hw->oss_type < 0)
104 		return -ENXIO;
105 #endif
106 
107 	if (!try_module_get(hw->card->module))
108 		return -EFAULT;
109 
110 	init_waitqueue_entry(&wait, current);
111 	add_wait_queue(&hw->open_wait, &wait);
112 	down(&hw->open_mutex);
113 	while (1) {
114 		if (hw->exclusive && hw->used > 0) {
115 			err = -EBUSY;
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 		up(&hw->open_mutex);
130 		schedule();
131 		down(&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 	up(&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 = -ENXIO;
157 	snd_hwdep_t *hw = file->private_data;
158 	down(&hw->open_mutex);
159 	if (hw->ops.release) {
160 		err = hw->ops.release(hw, file);
161 		wake_up(&hw->open_wait);
162 	}
163 	if (hw->used > 0)
164 		hw->used--;
165 	snd_card_file_remove(hw->card, file);
166 	up(&hw->open_mutex);
167 	module_put(hw->card->module);
168 	return err;
169 }
170 
171 static unsigned int snd_hwdep_poll(struct file * file, poll_table * wait)
172 {
173 	snd_hwdep_t *hw = file->private_data;
174 	if (hw->ops.poll)
175 		return hw->ops.poll(hw, file, wait);
176 	return 0;
177 }
178 
179 static int snd_hwdep_info(snd_hwdep_t *hw, snd_hwdep_info_t __user *_info)
180 {
181 	snd_hwdep_info_t info;
182 
183 	memset(&info, 0, sizeof(info));
184 	info.card = hw->card->number;
185 	strlcpy(info.id, hw->id, sizeof(info.id));
186 	strlcpy(info.name, hw->name, sizeof(info.name));
187 	info.iface = hw->iface;
188 	if (copy_to_user(_info, &info, sizeof(info)))
189 		return -EFAULT;
190 	return 0;
191 }
192 
193 static int snd_hwdep_dsp_status(snd_hwdep_t *hw, snd_hwdep_dsp_status_t __user *_info)
194 {
195 	snd_hwdep_dsp_status_t info;
196 	int err;
197 
198 	if (! hw->ops.dsp_status)
199 		return -ENXIO;
200 	memset(&info, 0, sizeof(info));
201 	info.dsp_loaded = hw->dsp_loaded;
202 	if ((err = hw->ops.dsp_status(hw, &info)) < 0)
203 		return err;
204 	if (copy_to_user(_info, &info, sizeof(info)))
205 		return -EFAULT;
206 	return 0;
207 }
208 
209 static int snd_hwdep_dsp_load(snd_hwdep_t *hw, snd_hwdep_dsp_image_t __user *_info)
210 {
211 	snd_hwdep_dsp_image_t info;
212 	int err;
213 
214 	if (! hw->ops.dsp_load)
215 		return -ENXIO;
216 	memset(&info, 0, sizeof(info));
217 	if (copy_from_user(&info, _info, sizeof(info)))
218 		return -EFAULT;
219 	/* check whether the dsp was already loaded */
220 	if (hw->dsp_loaded & (1 << info.index))
221 		return -EBUSY;
222 	if (!access_ok(VERIFY_READ, info.image, info.length))
223 		return -EFAULT;
224 	err = hw->ops.dsp_load(hw, &info);
225 	if (err < 0)
226 		return err;
227 	hw->dsp_loaded |= (1 << info.index);
228 	return 0;
229 }
230 
231 static long snd_hwdep_ioctl(struct file * file, unsigned int cmd, unsigned long arg)
232 {
233 	snd_hwdep_t *hw = file->private_data;
234 	void __user *argp = (void __user *)arg;
235 	switch (cmd) {
236 	case SNDRV_HWDEP_IOCTL_PVERSION:
237 		return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp);
238 	case SNDRV_HWDEP_IOCTL_INFO:
239 		return snd_hwdep_info(hw, argp);
240 	case SNDRV_HWDEP_IOCTL_DSP_STATUS:
241 		return snd_hwdep_dsp_status(hw, argp);
242 	case SNDRV_HWDEP_IOCTL_DSP_LOAD:
243 		return snd_hwdep_dsp_load(hw, argp);
244 	}
245 	if (hw->ops.ioctl)
246 		return hw->ops.ioctl(hw, file, cmd, arg);
247 	return -ENOTTY;
248 }
249 
250 static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma)
251 {
252 	snd_hwdep_t *hw = file->private_data;
253 	if (hw->ops.mmap)
254 		return hw->ops.mmap(hw, file, vma);
255 	return -ENXIO;
256 }
257 
258 static int snd_hwdep_control_ioctl(snd_card_t * card, snd_ctl_file_t * control,
259 				   unsigned int cmd, unsigned long arg)
260 {
261 	unsigned int tmp;
262 
263 	tmp = card->number * SNDRV_MINOR_HWDEPS;
264 	switch (cmd) {
265 	case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE:
266 		{
267 			int device;
268 
269 			if (get_user(device, (int __user *)arg))
270 				return -EFAULT;
271 			device = device < 0 ? 0 : device + 1;
272 			while (device < SNDRV_MINOR_HWDEPS) {
273 				if (snd_hwdep_devices[tmp + device])
274 					break;
275 				device++;
276 			}
277 			if (device >= SNDRV_MINOR_HWDEPS)
278 				device = -1;
279 			if (put_user(device, (int __user *)arg))
280 				return -EFAULT;
281 			return 0;
282 		}
283 	case SNDRV_CTL_IOCTL_HWDEP_INFO:
284 		{
285 			snd_hwdep_info_t __user *info = (snd_hwdep_info_t __user *)arg;
286 			int device;
287 			snd_hwdep_t *hwdep;
288 
289 			if (get_user(device, &info->device))
290 				return -EFAULT;
291 			if (device < 0 || device >= SNDRV_MINOR_HWDEPS)
292 				return -ENXIO;
293 			hwdep = snd_hwdep_devices[tmp + device];
294 			if (hwdep == NULL)
295 				return -ENXIO;
296 			return snd_hwdep_info(hwdep, info);
297 		}
298 	}
299 	return -ENOIOCTLCMD;
300 }
301 
302 #ifdef CONFIG_COMPAT
303 #include "hwdep_compat.c"
304 #else
305 #define snd_hwdep_ioctl_compat	NULL
306 #endif
307 
308 /*
309 
310  */
311 
312 static struct file_operations snd_hwdep_f_ops =
313 {
314 	.owner = 	THIS_MODULE,
315 	.llseek =	snd_hwdep_llseek,
316 	.read = 	snd_hwdep_read,
317 	.write =	snd_hwdep_write,
318 	.open =		snd_hwdep_open,
319 	.release =	snd_hwdep_release,
320 	.poll =		snd_hwdep_poll,
321 	.unlocked_ioctl =	snd_hwdep_ioctl,
322 	.compat_ioctl =	snd_hwdep_ioctl_compat,
323 	.mmap =		snd_hwdep_mmap,
324 };
325 
326 static snd_minor_t snd_hwdep_reg =
327 {
328 	.comment =	"hardware dependent",
329 	.f_ops =	&snd_hwdep_f_ops,
330 };
331 
332 /**
333  * snd_hwdep_new - create a new hwdep instance
334  * @card: the card instance
335  * @id: the id string
336  * @device: the device index (zero-based)
337  * @rhwdep: the pointer to store the new hwdep instance
338  *
339  * Creates a new hwdep instance with the given index on the card.
340  * The callbacks (hwdep->ops) must be set on the returned instance
341  * after this call manually by the caller.
342  *
343  * Returns zero if successful, or a negative error code on failure.
344  */
345 int snd_hwdep_new(snd_card_t * card, char *id, int device, snd_hwdep_t ** rhwdep)
346 {
347 	snd_hwdep_t *hwdep;
348 	int err;
349 	static snd_device_ops_t ops = {
350 		.dev_free = snd_hwdep_dev_free,
351 		.dev_register = snd_hwdep_dev_register,
352 		.dev_unregister = snd_hwdep_dev_unregister
353 	};
354 
355 	snd_assert(rhwdep != NULL, return -EINVAL);
356 	*rhwdep = NULL;
357 	snd_assert(card != NULL, return -ENXIO);
358 	hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
359 	if (hwdep == NULL)
360 		return -ENOMEM;
361 	hwdep->card = card;
362 	hwdep->device = device;
363 	if (id) {
364 		strlcpy(hwdep->id, id, sizeof(hwdep->id));
365 	}
366 #ifdef CONFIG_SND_OSSEMUL
367 	hwdep->oss_type = -1;
368 #endif
369 	if ((err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops)) < 0) {
370 		snd_hwdep_free(hwdep);
371 		return err;
372 	}
373 	init_waitqueue_head(&hwdep->open_wait);
374 	init_MUTEX(&hwdep->open_mutex);
375 	*rhwdep = hwdep;
376 	return 0;
377 }
378 
379 static int snd_hwdep_free(snd_hwdep_t *hwdep)
380 {
381 	snd_assert(hwdep != NULL, return -ENXIO);
382 	if (hwdep->private_free)
383 		hwdep->private_free(hwdep);
384 	kfree(hwdep);
385 	return 0;
386 }
387 
388 static int snd_hwdep_dev_free(snd_device_t *device)
389 {
390 	snd_hwdep_t *hwdep = device->device_data;
391 	return snd_hwdep_free(hwdep);
392 }
393 
394 static int snd_hwdep_dev_register(snd_device_t *device)
395 {
396 	snd_hwdep_t *hwdep = device->device_data;
397 	int idx, err;
398 	char name[32];
399 
400 	down(&register_mutex);
401 	idx = (hwdep->card->number * SNDRV_MINOR_HWDEPS) + hwdep->device;
402 	if (snd_hwdep_devices[idx]) {
403 		up(&register_mutex);
404 		return -EBUSY;
405 	}
406 	snd_hwdep_devices[idx] = hwdep;
407 	sprintf(name, "hwC%iD%i", hwdep->card->number, hwdep->device);
408 	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
409 				       hwdep->card, hwdep->device,
410 				       &snd_hwdep_reg, name)) < 0) {
411 		snd_printk(KERN_ERR "unable to register hardware dependent device %i:%i\n",
412 			   hwdep->card->number, hwdep->device);
413 		snd_hwdep_devices[idx] = NULL;
414 		up(&register_mutex);
415 		return err;
416 	}
417 #ifdef CONFIG_SND_OSSEMUL
418 	hwdep->ossreg = 0;
419 	if (hwdep->oss_type >= 0) {
420 		if ((hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM) && (hwdep->device != 0)) {
421 			snd_printk (KERN_WARNING "only hwdep device 0 can be registered as OSS direct FM device!\n");
422 		} else {
423 			if (snd_register_oss_device(hwdep->oss_type,
424 						    hwdep->card, hwdep->device,
425 						    &snd_hwdep_reg, hwdep->oss_dev) < 0) {
426 				snd_printk(KERN_ERR "unable to register OSS compatibility device %i:%i\n",
427 					   hwdep->card->number, hwdep->device);
428 			} else
429 				hwdep->ossreg = 1;
430 		}
431 	}
432 #endif
433 	up(&register_mutex);
434 	return 0;
435 }
436 
437 static int snd_hwdep_dev_unregister(snd_device_t *device)
438 {
439 	snd_hwdep_t *hwdep = device->device_data;
440 	int idx;
441 
442 	snd_assert(hwdep != NULL, return -ENXIO);
443 	down(&register_mutex);
444 	idx = (hwdep->card->number * SNDRV_MINOR_HWDEPS) + hwdep->device;
445 	if (snd_hwdep_devices[idx] != hwdep) {
446 		up(&register_mutex);
447 		return -EINVAL;
448 	}
449 #ifdef CONFIG_SND_OSSEMUL
450 	if (hwdep->ossreg)
451 		snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
452 #endif
453 	snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
454 	snd_hwdep_devices[idx] = NULL;
455 	up(&register_mutex);
456 	return snd_hwdep_free(hwdep);
457 }
458 
459 /*
460  *  Info interface
461  */
462 
463 static void snd_hwdep_proc_read(snd_info_entry_t *entry,
464 				snd_info_buffer_t * buffer)
465 {
466 	int idx;
467 	snd_hwdep_t *hwdep;
468 
469 	down(&register_mutex);
470 	for (idx = 0; idx < SNDRV_CARDS * SNDRV_MINOR_HWDEPS; idx++) {
471 		hwdep = snd_hwdep_devices[idx];
472 		if (hwdep == NULL)
473 			continue;
474 		snd_iprintf(buffer, "%02i-%02i: %s\n",
475 					idx / SNDRV_MINOR_HWDEPS,
476 					idx % SNDRV_MINOR_HWDEPS,
477 					hwdep->name);
478 	}
479 	up(&register_mutex);
480 }
481 
482 /*
483  *  ENTRY functions
484  */
485 
486 static snd_info_entry_t *snd_hwdep_proc_entry = NULL;
487 
488 static int __init alsa_hwdep_init(void)
489 {
490 	snd_info_entry_t *entry;
491 
492 	memset(snd_hwdep_devices, 0, sizeof(snd_hwdep_devices));
493 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
494 		entry->c.text.read_size = 512;
495 		entry->c.text.read = snd_hwdep_proc_read;
496 		if (snd_info_register(entry) < 0) {
497 			snd_info_free_entry(entry);
498 			entry = NULL;
499 		}
500 	}
501 	snd_hwdep_proc_entry = entry;
502 	snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
503 	snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl);
504 	return 0;
505 }
506 
507 static void __exit alsa_hwdep_exit(void)
508 {
509 	snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
510 	snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl);
511 	if (snd_hwdep_proc_entry) {
512 		snd_info_unregister(snd_hwdep_proc_entry);
513 		snd_hwdep_proc_entry = NULL;
514 	}
515 }
516 
517 module_init(alsa_hwdep_init)
518 module_exit(alsa_hwdep_exit)
519 
520 EXPORT_SYMBOL(snd_hwdep_new);
521