[ALSA] snd_hwdep_release() racefix
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / sound / core / hwdep.c
blob39c03f3dfbfa07d2a0dfed12ac5bf12480cfb8ac
1 /*
2 * Hardware dependent layer
3 * Copyright (c) by Jaroslav Kysela <perex@suse.cz>
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.
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.
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
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>
35 MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
36 MODULE_DESCRIPTION("Hardware dependent layer");
37 MODULE_LICENSE("GPL");
39 static LIST_HEAD(snd_hwdep_devices);
40 static DEFINE_MUTEX(register_mutex);
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);
48 static struct snd_hwdep *snd_hwdep_search(struct snd_card *card, int device)
50 struct snd_hwdep *hwdep;
52 list_for_each_entry(hwdep, &snd_hwdep_devices, list)
53 if (hwdep->card == card && hwdep->device == device)
54 return hwdep;
55 return NULL;
58 static loff_t snd_hwdep_llseek(struct file * file, loff_t offset, int orig)
60 struct snd_hwdep *hw = file->private_data;
61 if (hw->ops.llseek)
62 return hw->ops.llseek(hw, file, offset, orig);
63 return -ENXIO;
66 static ssize_t snd_hwdep_read(struct file * file, char __user *buf,
67 size_t count, loff_t *offset)
69 struct snd_hwdep *hw = file->private_data;
70 if (hw->ops.read)
71 return hw->ops.read(hw, buf, count, offset);
72 return -ENXIO;
75 static ssize_t snd_hwdep_write(struct file * file, const char __user *buf,
76 size_t count, loff_t *offset)
78 struct snd_hwdep *hw = file->private_data;
79 if (hw->ops.write)
80 return hw->ops.write(hw, buf, count, offset);
81 return -ENXIO;
84 static int snd_hwdep_open(struct inode *inode, struct file * file)
86 int major = imajor(inode);
87 struct snd_hwdep *hw;
88 int err;
89 wait_queue_t wait;
91 if (major == snd_major) {
92 hw = snd_lookup_minor_data(iminor(inode),
93 SNDRV_DEVICE_TYPE_HWDEP);
94 #ifdef CONFIG_SND_OSSEMUL
95 } else if (major == SOUND_MAJOR) {
96 hw = snd_lookup_oss_minor_data(iminor(inode),
97 SNDRV_OSS_DEVICE_TYPE_DMFM);
98 #endif
99 } else
100 return -ENXIO;
101 if (hw == NULL)
102 return -ENODEV;
104 if (!hw->ops.open)
105 return -ENXIO;
107 if (!try_module_get(hw->card->module))
108 return -EFAULT;
110 init_waitqueue_entry(&wait, current);
111 add_wait_queue(&hw->open_wait, &wait);
112 mutex_lock(&hw->open_mutex);
113 while (1) {
114 if (hw->exclusive && hw->used > 0) {
115 err = -EBUSY;
116 break;
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;
126 } else
127 break;
128 set_current_state(TASK_INTERRUPTIBLE);
129 mutex_unlock(&hw->open_mutex);
130 schedule();
131 mutex_lock(&hw->open_mutex);
132 if (signal_pending(current)) {
133 err = -ERESTARTSYS;
134 break;
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);
148 mutex_unlock(&hw->open_mutex);
149 if (err < 0)
150 module_put(hw->card->module);
151 return err;
154 static int snd_hwdep_release(struct inode *inode, struct file * file)
156 int err = -ENXIO;
157 struct snd_hwdep *hw = file->private_data;
158 struct module *mod = hw->card->module;
160 mutex_lock(&hw->open_mutex);
161 if (hw->ops.release)
162 err = hw->ops.release(hw, file);
163 if (hw->used > 0)
164 hw->used--;
165 mutex_unlock(&hw->open_mutex);
166 wake_up(&hw->open_wait);
168 snd_card_file_remove(hw->card, file);
169 module_put(mod);
170 return err;
173 static unsigned int snd_hwdep_poll(struct file * file, poll_table * wait)
175 struct snd_hwdep *hw = file->private_data;
176 if (hw->ops.poll)
177 return hw->ops.poll(hw, file, wait);
178 return 0;
181 static int snd_hwdep_info(struct snd_hwdep *hw,
182 struct snd_hwdep_info __user *_info)
184 struct snd_hwdep_info info;
186 memset(&info, 0, sizeof(info));
187 info.card = hw->card->number;
188 strlcpy(info.id, hw->id, sizeof(info.id));
189 strlcpy(info.name, hw->name, sizeof(info.name));
190 info.iface = hw->iface;
191 if (copy_to_user(_info, &info, sizeof(info)))
192 return -EFAULT;
193 return 0;
196 static int snd_hwdep_dsp_status(struct snd_hwdep *hw,
197 struct snd_hwdep_dsp_status __user *_info)
199 struct snd_hwdep_dsp_status info;
200 int err;
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;
213 static int snd_hwdep_dsp_load(struct snd_hwdep *hw,
214 struct snd_hwdep_dsp_image __user *_info)
216 struct snd_hwdep_dsp_image info;
217 int err;
219 if (! hw->ops.dsp_load)
220 return -ENXIO;
221 memset(&info, 0, sizeof(info));
222 if (copy_from_user(&info, _info, sizeof(info)))
223 return -EFAULT;
224 /* check whether the dsp was already loaded */
225 if (hw->dsp_loaded & (1 << info.index))
226 return -EBUSY;
227 if (!access_ok(VERIFY_READ, info.image, info.length))
228 return -EFAULT;
229 err = hw->ops.dsp_load(hw, &info);
230 if (err < 0)
231 return err;
232 hw->dsp_loaded |= (1 << info.index);
233 return 0;
236 static long snd_hwdep_ioctl(struct file * file, unsigned int cmd,
237 unsigned long arg)
239 struct snd_hwdep *hw = file->private_data;
240 void __user *argp = (void __user *)arg;
241 switch (cmd) {
242 case SNDRV_HWDEP_IOCTL_PVERSION:
243 return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp);
244 case SNDRV_HWDEP_IOCTL_INFO:
245 return snd_hwdep_info(hw, argp);
246 case SNDRV_HWDEP_IOCTL_DSP_STATUS:
247 return snd_hwdep_dsp_status(hw, argp);
248 case SNDRV_HWDEP_IOCTL_DSP_LOAD:
249 return snd_hwdep_dsp_load(hw, argp);
251 if (hw->ops.ioctl)
252 return hw->ops.ioctl(hw, file, cmd, arg);
253 return -ENOTTY;
256 static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma)
258 struct snd_hwdep *hw = file->private_data;
259 if (hw->ops.mmap)
260 return hw->ops.mmap(hw, file, vma);
261 return -ENXIO;
264 static int snd_hwdep_control_ioctl(struct snd_card *card,
265 struct snd_ctl_file * control,
266 unsigned int cmd, unsigned long arg)
268 switch (cmd) {
269 case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE:
271 int device;
273 if (get_user(device, (int __user *)arg))
274 return -EFAULT;
275 mutex_lock(&register_mutex);
276 device = device < 0 ? 0 : device + 1;
277 while (device < SNDRV_MINOR_HWDEPS) {
278 if (snd_hwdep_search(card, device))
279 break;
280 device++;
282 if (device >= SNDRV_MINOR_HWDEPS)
283 device = -1;
284 mutex_unlock(&register_mutex);
285 if (put_user(device, (int __user *)arg))
286 return -EFAULT;
287 return 0;
289 case SNDRV_CTL_IOCTL_HWDEP_INFO:
291 struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg;
292 int device, err;
293 struct snd_hwdep *hwdep;
295 if (get_user(device, &info->device))
296 return -EFAULT;
297 mutex_lock(&register_mutex);
298 hwdep = snd_hwdep_search(card, device);
299 if (hwdep)
300 err = snd_hwdep_info(hwdep, info);
301 else
302 err = -ENXIO;
303 mutex_unlock(&register_mutex);
304 return err;
307 return -ENOIOCTLCMD;
310 #ifdef CONFIG_COMPAT
311 #include "hwdep_compat.c"
312 #else
313 #define snd_hwdep_ioctl_compat NULL
314 #endif
320 static struct file_operations snd_hwdep_f_ops =
322 .owner = THIS_MODULE,
323 .llseek = snd_hwdep_llseek,
324 .read = snd_hwdep_read,
325 .write = snd_hwdep_write,
326 .open = snd_hwdep_open,
327 .release = snd_hwdep_release,
328 .poll = snd_hwdep_poll,
329 .unlocked_ioctl = snd_hwdep_ioctl,
330 .compat_ioctl = snd_hwdep_ioctl_compat,
331 .mmap = snd_hwdep_mmap,
335 * snd_hwdep_new - create a new hwdep instance
336 * @card: the card instance
337 * @id: the id string
338 * @device: the device index (zero-based)
339 * @rhwdep: the pointer to store the new hwdep instance
341 * Creates a new hwdep instance with the given index on the card.
342 * The callbacks (hwdep->ops) must be set on the returned instance
343 * after this call manually by the caller.
345 * Returns zero if successful, or a negative error code on failure.
347 int snd_hwdep_new(struct snd_card *card, char *id, int device,
348 struct snd_hwdep **rhwdep)
350 struct snd_hwdep *hwdep;
351 int err;
352 static struct snd_device_ops ops = {
353 .dev_free = snd_hwdep_dev_free,
354 .dev_register = snd_hwdep_dev_register,
355 .dev_disconnect = snd_hwdep_dev_disconnect,
358 snd_assert(rhwdep != NULL, return -EINVAL);
359 *rhwdep = NULL;
360 snd_assert(card != NULL, return -ENXIO);
361 hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
362 if (hwdep == NULL) {
363 snd_printk(KERN_ERR "hwdep: cannot allocate\n");
364 return -ENOMEM;
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;
377 init_waitqueue_head(&hwdep->open_wait);
378 mutex_init(&hwdep->open_mutex);
379 *rhwdep = hwdep;
380 return 0;
383 static int snd_hwdep_free(struct snd_hwdep *hwdep)
385 snd_assert(hwdep != NULL, return -ENXIO);
386 if (hwdep->private_free)
387 hwdep->private_free(hwdep);
388 kfree(hwdep);
389 return 0;
392 static int snd_hwdep_dev_free(struct snd_device *device)
394 struct snd_hwdep *hwdep = device->device_data;
395 return snd_hwdep_free(hwdep);
398 static int snd_hwdep_dev_register(struct snd_device *device)
400 struct snd_hwdep *hwdep = device->device_data;
401 int err;
402 char name[32];
404 mutex_lock(&register_mutex);
405 if (snd_hwdep_search(hwdep->card, hwdep->device)) {
406 mutex_unlock(&register_mutex);
407 return -EBUSY;
409 list_add_tail(&hwdep->list, &snd_hwdep_devices);
410 sprintf(name, "hwC%iD%i", hwdep->card->number, hwdep->device);
411 if ((err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
412 hwdep->card, hwdep->device,
413 &snd_hwdep_f_ops, hwdep, name)) < 0) {
414 snd_printk(KERN_ERR "unable to register hardware dependent device %i:%i\n",
415 hwdep->card->number, hwdep->device);
416 list_del(&hwdep->list);
417 mutex_unlock(&register_mutex);
418 return err;
420 #ifdef CONFIG_SND_OSSEMUL
421 hwdep->ossreg = 0;
422 if (hwdep->oss_type >= 0) {
423 if ((hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM) && (hwdep->device != 0)) {
424 snd_printk (KERN_WARNING "only hwdep device 0 can be registered as OSS direct FM device!\n");
425 } else {
426 if (snd_register_oss_device(hwdep->oss_type,
427 hwdep->card, hwdep->device,
428 &snd_hwdep_f_ops, hwdep,
429 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;
436 #endif
437 mutex_unlock(&register_mutex);
438 return 0;
441 static int snd_hwdep_dev_disconnect(struct snd_device *device)
443 struct snd_hwdep *hwdep = device->device_data;
445 snd_assert(hwdep != NULL, return -ENXIO);
446 mutex_lock(&register_mutex);
447 if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) {
448 mutex_unlock(&register_mutex);
449 return -EINVAL;
451 #ifdef CONFIG_SND_OSSEMUL
452 if (hwdep->ossreg)
453 snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
454 #endif
455 snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
456 list_del_init(&hwdep->list);
457 mutex_unlock(&register_mutex);
458 return 0;
461 #ifdef CONFIG_PROC_FS
463 * Info interface
466 static void snd_hwdep_proc_read(struct snd_info_entry *entry,
467 struct snd_info_buffer *buffer)
469 struct snd_hwdep *hwdep;
471 mutex_lock(&register_mutex);
472 list_for_each_entry(hwdep, &snd_hwdep_devices, list)
473 snd_iprintf(buffer, "%02i-%02i: %s\n",
474 hwdep->card->number, hwdep->device, hwdep->name);
475 mutex_unlock(&register_mutex);
478 static struct snd_info_entry *snd_hwdep_proc_entry;
480 static void __init snd_hwdep_proc_init(void)
482 struct snd_info_entry *entry;
484 if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
485 entry->c.text.read = snd_hwdep_proc_read;
486 if (snd_info_register(entry) < 0) {
487 snd_info_free_entry(entry);
488 entry = NULL;
491 snd_hwdep_proc_entry = entry;
494 static void __exit snd_hwdep_proc_done(void)
496 snd_info_free_entry(snd_hwdep_proc_entry);
498 #else /* !CONFIG_PROC_FS */
499 #define snd_hwdep_proc_init()
500 #define snd_hwdep_proc_done()
501 #endif /* CONFIG_PROC_FS */
505 * ENTRY functions
508 static int __init alsa_hwdep_init(void)
510 snd_hwdep_proc_init();
511 snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
512 snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl);
513 return 0;
516 static void __exit alsa_hwdep_exit(void)
518 snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
519 snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl);
520 snd_hwdep_proc_done();
523 module_init(alsa_hwdep_init)
524 module_exit(alsa_hwdep_exit)
526 EXPORT_SYMBOL(snd_hwdep_new);