kernel/sound/core/hwdep.c

   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 <linux/module.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@perex.cz>");
  35 MODULE_DESCRIPTION("Hardware dependent layer");
  36 MODULE_LICENSE("GPL");
  37
  38 static LIST_HEAD(snd_hwdep_devices);
  39 static DEFINE_MUTEX(register_mutex);
  40
  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                 snd_card_unref(hw->card);
 104                 return -EFAULT;
 105         }
 106
 107         init_waitqueue_entry(&wait, current);
 108         add_wait_queue(&hw->open_wait, &wait);
 109         mutex_lock(&hw->open_mutex);
 110         while (1) {
 111                 if (hw->exclusive && hw->used > 0) {
 112                         err = -EBUSY;
 113                         break;
 114                 }
 115                 if (!hw->ops.open) {
 116                         err = 0;
 117                         break;
 118                 }
 119                 err = hw->ops.open(hw, file);
 120                 if (err >= 0)
 121                         break;
 122                 if (err == -EAGAIN) {
 123                         if (file->f_flags & O_NONBLOCK) {
 124                                 err = -EBUSY;
 125                                 break;
 126                         }
 127                 } else
 128                         break;
 129                 set_current_state(TASK_INTERRUPTIBLE);
 130                 mutex_unlock(&hw->open_mutex);
 131                 schedule();
 132                 mutex_lock(&hw->open_mutex);
 133                 if (hw->card->shutdown) {
 134                         err = -ENODEV;
 135                         break;
 136                 }
 137                 if (signal_pending(current)) {
 138                         err = -ERESTARTSYS;
 139                         break;
 140                 }
 141         }
 142         remove_wait_queue(&hw->open_wait, &wait);
 143         if (err >= 0) {
 144                 err = snd_card_file_add(hw->card, file);
 145                 if (err >= 0) {
 146                         file->private_data = hw;
 147                         hw->used++;
 148                 } else {
 149                         if (hw->ops.release)
 150                                 hw->ops.release(hw, file);
 151                 }
 152         }
 153         mutex_unlock(&hw->open_mutex);
 154         if (err < 0)
 155                 module_put(hw->card->module);
 156         snd_card_unref(hw->card);
 157         return err;
 158 }
 159
 160 static int snd_hwdep_release(struct inode *inode, struct file * file)
 161 {
 162         int err = 0;
 163         struct snd_hwdep *hw = file->private_data;
 164         struct module *mod = hw->card->module;
 165
 166         mutex_lock(&hw->open_mutex);
 167         if (hw->ops.release)
 168                 err = hw->ops.release(hw, file);
 169         if (hw->used > 0)
 170                 hw->used--;
 171         mutex_unlock(&hw->open_mutex);
 172         wake_up(&hw->open_wait);
 173
 174         snd_card_file_remove(hw->card, file);
 175         module_put(mod);
 176         return err;
 177 }
 178
 179 static unsigned int snd_hwdep_poll(struct file * file, poll_table * wait)
 180 {
 181         struct snd_hwdep *hw = file->private_data;
 182         if (hw->ops.poll)
 183                 return hw->ops.poll(hw, file, wait);
 184         return 0;
 185 }
 186
 187 static int snd_hwdep_info(struct snd_hwdep *hw,
 188                           struct snd_hwdep_info __user *_info)
 189 {
 190         struct snd_hwdep_info info;
 191
 192         memset(&info, 0, sizeof(info));
 193         info.card = hw->card->number;
 194         strlcpy(info.id, hw->id, sizeof(info.id));
 195         strlcpy(info.name, hw->name, sizeof(info.name));
 196         info.iface = hw->iface;
 197         if (copy_to_user(_info, &info, sizeof(info)))
 198                 return -EFAULT;
 199         return 0;
 200 }
 201
 202 static int snd_hwdep_dsp_status(struct snd_hwdep *hw,
 203                                 struct snd_hwdep_dsp_status __user *_info)
 204 {
 205         struct snd_hwdep_dsp_status info;
 206         int err;
 207
 208         if (! hw->ops.dsp_status)
 209                 return -ENXIO;
 210         memset(&info, 0, sizeof(info));
 211         info.dsp_loaded = hw->dsp_loaded;
 212         if ((err = hw->ops.dsp_status(hw, &info)) < 0)
 213                 return err;
 214         if (copy_to_user(_info, &info, sizeof(info)))
 215                 return -EFAULT;
 216         return 0;
 217 }
 218
 219 static int snd_hwdep_dsp_load(struct snd_hwdep *hw,
 220                               struct snd_hwdep_dsp_image __user *_info)
 221 {
 222         struct snd_hwdep_dsp_image info;
 223         int err;
 224
 225         if (! hw->ops.dsp_load)
 226                 return -ENXIO;
 227         memset(&info, 0, sizeof(info));
 228         if (copy_from_user(&info, _info, sizeof(info)))
 229                 return -EFAULT;
 230         /* check whether the dsp was already loaded */
 231         if (hw->dsp_loaded & (1 << info.index))
 232                 return -EBUSY;
 233         if (!access_ok(VERIFY_READ, info.image, info.length))
 234                 return -EFAULT;
 235         err = hw->ops.dsp_load(hw, &info);
 236         if (err < 0)
 237                 return err;
 238         hw->dsp_loaded |= (1 << info.index);
 239         return 0;
 240 }
 241
 242 static long snd_hwdep_ioctl(struct file * file, unsigned int cmd,
 243                             unsigned long arg)
 244 {
 245         struct snd_hwdep *hw = file->private_data;
 246         void __user *argp = (void __user *)arg;
 247         switch (cmd) {
 248         case SNDRV_HWDEP_IOCTL_PVERSION:
 249                 return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp);
 250         case SNDRV_HWDEP_IOCTL_INFO:
 251                 return snd_hwdep_info(hw, argp);
 252         case SNDRV_HWDEP_IOCTL_DSP_STATUS:
 253                 return snd_hwdep_dsp_status(hw, argp);
 254         case SNDRV_HWDEP_IOCTL_DSP_LOAD:
 255                 return snd_hwdep_dsp_load(hw, argp);
 256         }
 257         if (hw->ops.ioctl)
 258                 return hw->ops.ioctl(hw, file, cmd, arg);
 259         return -ENOTTY;
 260 }
 261
 262 static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma)
 263 {
 264         struct snd_hwdep *hw = file->private_data;
 265         if (hw->ops.mmap)
 266                 return hw->ops.mmap(hw, file, vma);
 267         return -ENXIO;
 268 }
 269
 270 static int snd_hwdep_control_ioctl(struct snd_card *card,
 271                                    struct snd_ctl_file * control,
 272                                    unsigned int cmd, unsigned long arg)
 273 {
 274         switch (cmd) {
 275         case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE:
 276                 {
 277                         int device;
 278
 279                         if (get_user(device, (int __user *)arg))
 280                                 return -EFAULT;
 281                         mutex_lock(&register_mutex);
 282
 283                         if (device < 0)
 284                                 device = 0;
 285                         else if (device < SNDRV_MINOR_HWDEPS)
 286                                 device++;
 287                         else
 288                                 device = SNDRV_MINOR_HWDEPS;
 289
 290                         while (device < SNDRV_MINOR_HWDEPS) {
 291                                 if (snd_hwdep_search(card, device))
 292                                         break;
 293                                 device++;
 294                         }
 295                         if (device >= SNDRV_MINOR_HWDEPS)
 296                                 device = -1;
 297                         mutex_unlock(&register_mutex);
 298                         if (put_user(device, (int __user *)arg))
 299                                 return -EFAULT;
 300                         return 0;
 301                 }
 302         case SNDRV_CTL_IOCTL_HWDEP_INFO:
 303                 {
 304                         struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg;
 305                         int device, err;
 306                         struct snd_hwdep *hwdep;
 307
 308                         if (get_user(device, &info->device))
 309                                 return -EFAULT;
 310                         mutex_lock(&register_mutex);
 311                         hwdep = snd_hwdep_search(card, device);
 312                         if (hwdep)
 313                                 err = snd_hwdep_info(hwdep, info);
 314                         else
 315                                 err = -ENXIO;
 316                         mutex_unlock(&register_mutex);
 317                         return err;
 318                 }
 319         }
 320         return -ENOIOCTLCMD;
 321 }
 322
 323 #ifdef CONFIG_COMPAT
 324 #include "hwdep_compat.c"
 325 #else
 326 #define snd_hwdep_ioctl_compat  NULL
 327 #endif
 328
 329 /*
 330
 331  */
 332
 333 static const struct file_operations snd_hwdep_f_ops =
 334 {
 335         .owner =        THIS_MODULE,
 336         .llseek =       snd_hwdep_llseek,
 337         .read =         snd_hwdep_read,
 338         .write =        snd_hwdep_write,
 339         .open =         snd_hwdep_open,
 340         .release =      snd_hwdep_release,
 341         .poll =         snd_hwdep_poll,
 342         .unlocked_ioctl =       snd_hwdep_ioctl,
 343         .compat_ioctl = snd_hwdep_ioctl_compat,
 344         .mmap =         snd_hwdep_mmap,
 345 };
 346
 347 static void release_hwdep_device(struct device *dev)
 348 {
 349         kfree(container_of(dev, struct snd_hwdep, dev));
 350 }
 351
 352 /**
 353  * snd_hwdep_new - create a new hwdep instance
 354  * @card: the card instance
 355  * @id: the id string
 356  * @device: the device index (zero-based)
 357  * @rhwdep: the pointer to store the new hwdep instance
 358  *
 359  * Creates a new hwdep instance with the given index on the card.
 360  * The callbacks (hwdep->ops) must be set on the returned instance
 361  * after this call manually by the caller.
 362  *
 363  * Return: Zero if successful, or a negative error code on failure.
 364  */
 365 int snd_hwdep_new(struct snd_card *card, char *id, int device,
 366                   struct snd_hwdep **rhwdep)
 367 {
 368         struct snd_hwdep *hwdep;
 369         int err;
 370         static struct snd_device_ops ops = {
 371                 .dev_free = snd_hwdep_dev_free,
 372                 .dev_register = snd_hwdep_dev_register,
 373                 .dev_disconnect = snd_hwdep_dev_disconnect,
 374         };
 375
 376         if (snd_BUG_ON(!card))
 377                 return -ENXIO;
 378         if (rhwdep)
 379                 *rhwdep = NULL;
 380         hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
 381         if (!hwdep)
 382                 return -ENOMEM;
 383
 384         init_waitqueue_head(&hwdep->open_wait);
 385         mutex_init(&hwdep->open_mutex);
 386         hwdep->card = card;
 387         hwdep->device = device;
 388         if (id)
 389                 strlcpy(hwdep->id, id, sizeof(hwdep->id));
 390
 391         snd_device_initialize(&hwdep->dev, card);
 392         hwdep->dev.release = release_hwdep_device;
 393         dev_set_name(&hwdep->dev, "hwC%iD%i", card->number, device);
 394 #ifdef CONFIG_SND_OSSEMUL
 395         hwdep->oss_type = -1;
 396 #endif
 397
 398         err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops);
 399         if (err < 0) {
 400                 put_device(&hwdep->dev);
 401                 return err;
 402         }
 403
 404         if (rhwdep)
 405                 *rhwdep = hwdep;
 406         return 0;
 407 }
 408 EXPORT_SYMBOL(snd_hwdep_new);
 409
 410 static int snd_hwdep_dev_free(struct snd_device *device)
 411 {
 412         struct snd_hwdep *hwdep = device->device_data;
 413         if (!hwdep)
 414                 return 0;
 415         if (hwdep->private_free)
 416                 hwdep->private_free(hwdep);
 417         put_device(&hwdep->dev);
 418         return 0;
 419 }
 420
 421 static int snd_hwdep_dev_register(struct snd_device *device)
 422 {
 423         struct snd_hwdep *hwdep = device->device_data;
 424         struct snd_card *card = hwdep->card;
 425         int err;
 426
 427         mutex_lock(&register_mutex);
 428         if (snd_hwdep_search(card, hwdep->device)) {
 429                 mutex_unlock(&register_mutex);
 430                 return -EBUSY;
 431         }
 432         list_add_tail(&hwdep->list, &snd_hwdep_devices);
 433         err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
 434                                   hwdep->card, hwdep->device,
 435                                   &snd_hwdep_f_ops, hwdep, &hwdep->dev);
 436         if (err < 0) {
 437                 dev_err(&hwdep->dev, "unable to register\n");
 438                 list_del(&hwdep->list);
 439                 mutex_unlock(&register_mutex);
 440                 return err;
 441         }
 442
 443 #ifdef CONFIG_SND_OSSEMUL
 444         hwdep->ossreg = 0;
 445         if (hwdep->oss_type >= 0) {
 446                 if (hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM &&
 447                     hwdep->device)
 448                         dev_warn(&hwdep->dev,
 449                                  "only hwdep device 0 can be registered as OSS direct FM device!\n");
 450                 else if (snd_register_oss_device(hwdep->oss_type,
 451                                                  card, hwdep->device,
 452                                                  &snd_hwdep_f_ops, hwdep) < 0)
 453                         dev_warn(&hwdep->dev,
 454                                  "unable to register OSS compatibility device\n");
 455                 else
 456                         hwdep->ossreg = 1;
 457         }
 458 #endif
 459         mutex_unlock(&register_mutex);
 460         return 0;
 461 }
 462
 463 static int snd_hwdep_dev_disconnect(struct snd_device *device)
 464 {
 465         struct snd_hwdep *hwdep = device->device_data;
 466
 467         if (snd_BUG_ON(!hwdep))
 468                 return -ENXIO;
 469         mutex_lock(&register_mutex);
 470         if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) {
 471                 mutex_unlock(&register_mutex);
 472                 return -EINVAL;
 473         }
 474         mutex_lock(&hwdep->open_mutex);
 475         wake_up(&hwdep->open_wait);
 476 #ifdef CONFIG_SND_OSSEMUL
 477         if (hwdep->ossreg)
 478                 snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
 479 #endif
 480         snd_unregister_device(&hwdep->dev);
 481         list_del_init(&hwdep->list);
 482         mutex_unlock(&hwdep->open_mutex);
 483         mutex_unlock(&register_mutex);
 484         return 0;
 485 }
 486
 487 #ifdef CONFIG_PROC_FS
 488 /*
 489  *  Info interface
 490  */
 491
 492 static void snd_hwdep_proc_read(struct snd_info_entry *entry,
 493                                 struct snd_info_buffer *buffer)
 494 {
 495         struct snd_hwdep *hwdep;
 496
 497         mutex_lock(&register_mutex);
 498         list_for_each_entry(hwdep, &snd_hwdep_devices, list)
 499                 snd_iprintf(buffer, "%02i-%02i: %s\n",
 500                             hwdep->card->number, hwdep->device, hwdep->name);
 501         mutex_unlock(&register_mutex);
 502 }
 503
 504 static struct snd_info_entry *snd_hwdep_proc_entry;
 505
 506 static void __init snd_hwdep_proc_init(void)
 507 {
 508         struct snd_info_entry *entry;
 509
 510         if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
 511                 entry->c.text.read = snd_hwdep_proc_read;
 512                 if (snd_info_register(entry) < 0) {
 513                         snd_info_free_entry(entry);
 514                         entry = NULL;
 515                 }
 516         }
 517         snd_hwdep_proc_entry = entry;
 518 }
 519
 520 static void __exit snd_hwdep_proc_done(void)
 521 {
 522         snd_info_free_entry(snd_hwdep_proc_entry);
 523 }
 524 #else /* !CONFIG_PROC_FS */
 525 #define snd_hwdep_proc_init()
 526 #define snd_hwdep_proc_done()
 527 #endif /* CONFIG_PROC_FS */
 528
 529
 530 /*
 531  *  ENTRY functions
 532  */
 533
 534 static int __init alsa_hwdep_init(void)
 535 {
 536         snd_hwdep_proc_init();
 537         snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
 538         snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl);
 539         return 0;
 540 }
 541
 542 static void __exit alsa_hwdep_exit(void)
 543 {
 544         snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
 545         snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl);
 546         snd_hwdep_proc_done();
 547 }
 548
 549 module_init(alsa_hwdep_init)
 550 module_exit(alsa_hwdep_exit)