[PATCH] gfp flags annotations - part 1
[linux-2.6] / sound / core / hwdep.c
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);