xref: /openbmc/linux/sound/core/hwdep.c (revision d5cb9783536a41df9f9cba5b0a1d78047ed787f7)
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 	switch (major) {
85 	case CONFIG_SND_MAJOR:
86 		cardnum = SNDRV_MINOR_CARD(iminor(inode));
87 		device = SNDRV_MINOR_DEVICE(iminor(inode)) - SNDRV_MINOR_HWDEP;
88 		break;
89 #ifdef CONFIG_SND_OSSEMUL
90 	case SOUND_MAJOR:
91 		cardnum = SNDRV_MINOR_OSS_CARD(iminor(inode));
92 		device = 0;
93 		break;
94 #endif
95 	default:
96 		return -ENXIO;
97 	}
98 	cardnum %= SNDRV_CARDS;
99 	device %= SNDRV_MINOR_HWDEPS;
100 	hw = snd_hwdep_devices[(cardnum * SNDRV_MINOR_HWDEPS) + device];
101 	if (hw == NULL)
102 		return -ENODEV;
103 
104 	if (!hw->ops.open)
105 		return -ENXIO;
106 #ifdef CONFIG_SND_OSSEMUL
107 	if (major == SOUND_MAJOR && hw->oss_type < 0)
108 		return -ENXIO;
109 #endif
110 
111 	if (!try_module_get(hw->card->module))
112 		return -EFAULT;
113 
114 	init_waitqueue_entry(&wait, current);
115 	add_wait_queue(&hw->open_wait, &wait);
116 	down(&hw->open_mutex);
117 	while (1) {
118 		if (hw->exclusive && hw->used > 0) {
119 			err = -EBUSY;
120 			break;
121 		}
122 		err = hw->ops.open(hw, file);
123 		if (err >= 0)
124 			break;
125 		if (err == -EAGAIN) {
126 			if (file->f_flags & O_NONBLOCK) {
127 				err = -EBUSY;
128 				break;
129 			}
130 		} else
131 			break;
132 		set_current_state(TASK_INTERRUPTIBLE);
133 		up(&hw->open_mutex);
134 		schedule();
135 		down(&hw->open_mutex);
136 		if (signal_pending(current)) {
137 			err = -ERESTARTSYS;
138 			break;
139 		}
140 	}
141 	remove_wait_queue(&hw->open_wait, &wait);
142 	if (err >= 0) {
143 		err = snd_card_file_add(hw->card, file);
144 		if (err >= 0) {
145 			file->private_data = hw;
146 			hw->used++;
147 		} else {
148 			if (hw->ops.release)
149 				hw->ops.release(hw, file);
150 		}
151 	}
152 	up(&hw->open_mutex);
153 	if (err < 0)
154 		module_put(hw->card->module);
155 	return err;
156 }
157 
158 static int snd_hwdep_release(struct inode *inode, struct file * file)
159 {
160 	int err = -ENXIO;
161 	snd_hwdep_t *hw = file->private_data;
162 	down(&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 	up(&hw->open_mutex);
171 	module_put(hw->card->module);
172 	return err;
173 }
174 
175 static unsigned int snd_hwdep_poll(struct file * file, poll_table * wait)
176 {
177 	snd_hwdep_t *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(snd_hwdep_t *hw, snd_hwdep_info_t __user *_info)
184 {
185 	snd_hwdep_info_t info;
186 
187 	memset(&info, 0, sizeof(info));
188 	info.card = hw->card->number;
189 	strlcpy(info.id, hw->id, sizeof(info.id));
190 	strlcpy(info.name, hw->name, sizeof(info.name));
191 	info.iface = hw->iface;
192 	if (copy_to_user(_info, &info, sizeof(info)))
193 		return -EFAULT;
194 	return 0;
195 }
196 
197 static int snd_hwdep_dsp_status(snd_hwdep_t *hw, snd_hwdep_dsp_status_t __user *_info)
198 {
199 	snd_hwdep_dsp_status_t 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(snd_hwdep_t *hw, snd_hwdep_dsp_image_t __user *_info)
214 {
215 	snd_hwdep_dsp_image_t 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, unsigned long arg)
236 {
237 	snd_hwdep_t *hw = file->private_data;
238 	void __user *argp = (void __user *)arg;
239 	switch (cmd) {
240 	case SNDRV_HWDEP_IOCTL_PVERSION:
241 		return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp);
242 	case SNDRV_HWDEP_IOCTL_INFO:
243 		return snd_hwdep_info(hw, argp);
244 	case SNDRV_HWDEP_IOCTL_DSP_STATUS:
245 		return snd_hwdep_dsp_status(hw, argp);
246 	case SNDRV_HWDEP_IOCTL_DSP_LOAD:
247 		return snd_hwdep_dsp_load(hw, argp);
248 	}
249 	if (hw->ops.ioctl)
250 		return hw->ops.ioctl(hw, file, cmd, arg);
251 	return -ENOTTY;
252 }
253 
254 static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma)
255 {
256 	snd_hwdep_t *hw = file->private_data;
257 	if (hw->ops.mmap)
258 		return hw->ops.mmap(hw, file, vma);
259 	return -ENXIO;
260 }
261 
262 static int snd_hwdep_control_ioctl(snd_card_t * card, snd_ctl_file_t * control,
263 				   unsigned int cmd, unsigned long arg)
264 {
265 	unsigned int tmp;
266 
267 	tmp = card->number * SNDRV_MINOR_HWDEPS;
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 			device = device < 0 ? 0 : device + 1;
276 			while (device < SNDRV_MINOR_HWDEPS) {
277 				if (snd_hwdep_devices[tmp + device])
278 					break;
279 				device++;
280 			}
281 			if (device >= SNDRV_MINOR_HWDEPS)
282 				device = -1;
283 			if (put_user(device, (int __user *)arg))
284 				return -EFAULT;
285 			return 0;
286 		}
287 	case SNDRV_CTL_IOCTL_HWDEP_INFO:
288 		{
289 			snd_hwdep_info_t __user *info = (snd_hwdep_info_t __user *)arg;
290 			int device;
291 			snd_hwdep_t *hwdep;
292 
293 			if (get_user(device, &info->device))
294 				return -EFAULT;
295 			if (device < 0 || device >= SNDRV_MINOR_HWDEPS)
296 				return -ENXIO;
297 			hwdep = snd_hwdep_devices[tmp + device];
298 			if (hwdep == NULL)
299 				return -ENXIO;
300 			return snd_hwdep_info(hwdep, info);
301 		}
302 	}
303 	return -ENOIOCTLCMD;
304 }
305 
306 #ifdef CONFIG_COMPAT
307 #include "hwdep_compat.c"
308 #else
309 #define snd_hwdep_ioctl_compat	NULL
310 #endif
311 
312 /*
313 
314  */
315 
316 static struct file_operations snd_hwdep_f_ops =
317 {
318 	.owner = 	THIS_MODULE,
319 	.llseek =	snd_hwdep_llseek,
320 	.read = 	snd_hwdep_read,
321 	.write =	snd_hwdep_write,
322 	.open =		snd_hwdep_open,
323 	.release =	snd_hwdep_release,
324 	.poll =		snd_hwdep_poll,
325 	.unlocked_ioctl =	snd_hwdep_ioctl,
326 	.compat_ioctl =	snd_hwdep_ioctl_compat,
327 	.mmap =		snd_hwdep_mmap,
328 };
329 
330 static snd_minor_t snd_hwdep_reg =
331 {
332 	.comment =	"hardware dependent",
333 	.f_ops =	&snd_hwdep_f_ops,
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(snd_card_t * card, char *id, int device, snd_hwdep_t ** rhwdep)
350 {
351 	snd_hwdep_t *hwdep;
352 	int err;
353 	static snd_device_ops_t ops = {
354 		.dev_free = snd_hwdep_dev_free,
355 		.dev_register = snd_hwdep_dev_register,
356 		.dev_unregister = snd_hwdep_dev_unregister
357 	};
358 
359 	snd_assert(rhwdep != NULL, return -EINVAL);
360 	*rhwdep = NULL;
361 	snd_assert(card != NULL, return -ENXIO);
362 	hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
363 	if (hwdep == NULL)
364 		return -ENOMEM;
365 	hwdep->card = card;
366 	hwdep->device = device;
367 	if (id) {
368 		strlcpy(hwdep->id, id, sizeof(hwdep->id));
369 	}
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 	init_MUTEX(&hwdep->open_mutex);
379 	*rhwdep = hwdep;
380 	return 0;
381 }
382 
383 static int snd_hwdep_free(snd_hwdep_t *hwdep)
384 {
385 	snd_assert(hwdep != NULL, return -ENXIO);
386 	if (hwdep->private_free)
387 		hwdep->private_free(hwdep);
388 	kfree(hwdep);
389 	return 0;
390 }
391 
392 static int snd_hwdep_dev_free(snd_device_t *device)
393 {
394 	snd_hwdep_t *hwdep = device->device_data;
395 	return snd_hwdep_free(hwdep);
396 }
397 
398 static int snd_hwdep_dev_register(snd_device_t *device)
399 {
400 	snd_hwdep_t *hwdep = device->device_data;
401 	int idx, err;
402 	char name[32];
403 
404 	down(&register_mutex);
405 	idx = (hwdep->card->number * SNDRV_MINOR_HWDEPS) + hwdep->device;
406 	if (snd_hwdep_devices[idx]) {
407 		up(&register_mutex);
408 		return -EBUSY;
409 	}
410 	snd_hwdep_devices[idx] = hwdep;
411 	sprintf(name, "hwC%iD%i", hwdep->card->number, hwdep->device);
412 	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
413 				       hwdep->card, hwdep->device,
414 				       &snd_hwdep_reg, name)) < 0) {
415 		snd_printk(KERN_ERR "unable to register hardware dependent device %i:%i\n",
416 			   hwdep->card->number, hwdep->device);
417 		snd_hwdep_devices[idx] = NULL;
418 		up(&register_mutex);
419 		return err;
420 	}
421 #ifdef CONFIG_SND_OSSEMUL
422 	hwdep->ossreg = 0;
423 	if (hwdep->oss_type >= 0) {
424 		if ((hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM) && (hwdep->device != 0)) {
425 			snd_printk (KERN_WARNING "only hwdep device 0 can be registered as OSS direct FM device!\n");
426 		} else {
427 			if (snd_register_oss_device(hwdep->oss_type,
428 						    hwdep->card, hwdep->device,
429 						    &snd_hwdep_reg, hwdep->oss_dev) < 0) {
430 				snd_printk(KERN_ERR "unable to register OSS compatibility device %i:%i\n",
431 					   hwdep->card->number, hwdep->device);
432 			} else
433 				hwdep->ossreg = 1;
434 		}
435 	}
436 #endif
437 	up(&register_mutex);
438 	return 0;
439 }
440 
441 static int snd_hwdep_dev_unregister(snd_device_t *device)
442 {
443 	snd_hwdep_t *hwdep = device->device_data;
444 	int idx;
445 
446 	snd_assert(hwdep != NULL, return -ENXIO);
447 	down(&register_mutex);
448 	idx = (hwdep->card->number * SNDRV_MINOR_HWDEPS) + hwdep->device;
449 	if (snd_hwdep_devices[idx] != hwdep) {
450 		up(&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 	snd_hwdep_devices[idx] = NULL;
459 	up(&register_mutex);
460 	return snd_hwdep_free(hwdep);
461 }
462 
463 /*
464  *  Info interface
465  */
466 
467 static void snd_hwdep_proc_read(snd_info_entry_t *entry,
468 				snd_info_buffer_t * buffer)
469 {
470 	int idx;
471 	snd_hwdep_t *hwdep;
472 
473 	down(&register_mutex);
474 	for (idx = 0; idx < SNDRV_CARDS * SNDRV_MINOR_HWDEPS; idx++) {
475 		hwdep = snd_hwdep_devices[idx];
476 		if (hwdep == NULL)
477 			continue;
478 		snd_iprintf(buffer, "%02i-%02i: %s\n",
479 					idx / SNDRV_MINOR_HWDEPS,
480 					idx % SNDRV_MINOR_HWDEPS,
481 					hwdep->name);
482 	}
483 	up(&register_mutex);
484 }
485 
486 /*
487  *  ENTRY functions
488  */
489 
490 static snd_info_entry_t *snd_hwdep_proc_entry = NULL;
491 
492 static int __init alsa_hwdep_init(void)
493 {
494 	snd_info_entry_t *entry;
495 
496 	memset(snd_hwdep_devices, 0, sizeof(snd_hwdep_devices));
497 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
498 		entry->c.text.read_size = 512;
499 		entry->c.text.read = snd_hwdep_proc_read;
500 		if (snd_info_register(entry) < 0) {
501 			snd_info_free_entry(entry);
502 			entry = NULL;
503 		}
504 	}
505 	snd_hwdep_proc_entry = entry;
506 	snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
507 	snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl);
508 	return 0;
509 }
510 
511 static void __exit alsa_hwdep_exit(void)
512 {
513 	snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
514 	snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl);
515 	if (snd_hwdep_proc_entry) {
516 		snd_info_unregister(snd_hwdep_proc_entry);
517 		snd_hwdep_proc_entry = NULL;
518 	}
519 }
520 
521 module_init(alsa_hwdep_init)
522 module_exit(alsa_hwdep_exit)
523 
524 EXPORT_SYMBOL(snd_hwdep_new);
525