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 (verify_area(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 inline int _snd_hwdep_ioctl(struct inode *inode, struct file * file,
 236                                    unsigned int cmd, unsigned long arg)
 237 {
 238         snd_hwdep_t *hw = file->private_data;
 239         void __user *argp = (void __user *)arg;
 240         switch (cmd) {
 241         case SNDRV_HWDEP_IOCTL_PVERSION:
 242                 return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp);
 243         case SNDRV_HWDEP_IOCTL_INFO:
 244                 return snd_hwdep_info(hw, argp);
 245         case SNDRV_HWDEP_IOCTL_DSP_STATUS:
 246                 return snd_hwdep_dsp_status(hw, argp);
 247         case SNDRV_HWDEP_IOCTL_DSP_LOAD:
 248                 return snd_hwdep_dsp_load(hw, argp);
 249         }
 250         if (hw->ops.ioctl)
 251                 return hw->ops.ioctl(hw, file, cmd, arg);
 252         return -ENOTTY;
 253 }
 254
 255 /* FIXME: need to unlock BKL to allow preemption */
 256 static int snd_hwdep_ioctl(struct inode *inode, struct file * file,
 257                            unsigned int cmd, unsigned long arg)
 258 {
 259         int err;
 260         unlock_kernel();
 261         err = _snd_hwdep_ioctl(inode, file, cmd, arg);
 262         lock_kernel();
 263         return err;
 264 }
 265
 266 static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma)
 267 {
 268         snd_hwdep_t *hw = file->private_data;
 269         if (hw->ops.mmap)
 270                 return hw->ops.mmap(hw, file, vma);
 271         return -ENXIO;
 272 }
 273
 274 static int snd_hwdep_control_ioctl(snd_card_t * card, snd_ctl_file_t * control,
 275                                    unsigned int cmd, unsigned long arg)
 276 {
 277         unsigned int tmp;
 278
 279         tmp = card->number * SNDRV_MINOR_HWDEPS;
 280         switch (cmd) {
 281         case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE:
 282                 {
 283                         int device;
 284
 285                         if (get_user(device, (int __user *)arg))
 286                                 return -EFAULT;
 287                         device = device < 0 ? 0 : device + 1;
 288                         while (device < SNDRV_MINOR_HWDEPS) {
 289                                 if (snd_hwdep_devices[tmp + device])
 290                                         break;
 291                                 device++;
 292                         }
 293                         if (device >= SNDRV_MINOR_HWDEPS)
 294                                 device = -1;
 295                         if (put_user(device, (int __user *)arg))
 296                                 return -EFAULT;
 297                         return 0;
 298                 }
 299         case SNDRV_CTL_IOCTL_HWDEP_INFO:
 300                 {
 301                         snd_hwdep_info_t __user *info = (snd_hwdep_info_t __user *)arg;
 302                         int device;
 303                         snd_hwdep_t *hwdep;
 304
 305                         if (get_user(device, &info->device))
 306                                 return -EFAULT;
 307                         if (device < 0 || device >= SNDRV_MINOR_HWDEPS)
 308                                 return -ENXIO;
 309                         hwdep = snd_hwdep_devices[tmp + device];
 310                         if (hwdep == NULL)
 311                                 return -ENXIO;
 312                         return snd_hwdep_info(hwdep, info);
 313                 }
 314         }
 315         return -ENOIOCTLCMD;
 316 }
 317
 318 /*
 319
 320  */
 321
 322 static struct file_operations snd_hwdep_f_ops =
 323 {
 324         .owner =        THIS_MODULE,
 325         .llseek =       snd_hwdep_llseek,
 326         .read =         snd_hwdep_read,
 327         .write =        snd_hwdep_write,
 328         .open =         snd_hwdep_open,
 329         .release =      snd_hwdep_release,
 330         .poll =         snd_hwdep_poll,
 331         .ioctl =        snd_hwdep_ioctl,
 332         .mmap =         snd_hwdep_mmap,
 333 };
 334
 335 static snd_minor_t snd_hwdep_reg =
 336 {
 337         .comment =      "hardware dependent",
 338         .f_ops =        &snd_hwdep_f_ops,
 339 };
 340
 341 /**
 342  * snd_hwdep_new - create a new hwdep instance
 343  * @card: the card instance
 344  * @id: the id string
 345  * @device: the device index (zero-based)
 346  * @rhwdep: the pointer to store the new hwdep instance
 347  *
 348  * Creates a new hwdep instance with the given index on the card.
 349  * The callbacks (hwdep->ops) must be set on the returned instance
 350  * after this call manually by the caller.
 351  *
 352  * Returns zero if successful, or a negative error code on failure.
 353  */
 354 int snd_hwdep_new(snd_card_t * card, char *id, int device, snd_hwdep_t ** rhwdep)
 355 {
 356         snd_hwdep_t *hwdep;
 357         int err;
 358         static snd_device_ops_t ops = {
 359                 .dev_free = snd_hwdep_dev_free,
 360                 .dev_register = snd_hwdep_dev_register,
 361                 .dev_unregister = snd_hwdep_dev_unregister
 362         };
 363
 364         snd_assert(rhwdep != NULL, return -EINVAL);
 365         *rhwdep = NULL;
 366         snd_assert(card != NULL, return -ENXIO);
 367         hwdep = kcalloc(1, sizeof(*hwdep), GFP_KERNEL);
 368         if (hwdep == NULL)
 369                 return -ENOMEM;
 370         hwdep->card = card;
 371         hwdep->device = device;
 372         if (id) {
 373                 strlcpy(hwdep->id, id, sizeof(hwdep->id));
 374         }
 375 #ifdef CONFIG_SND_OSSEMUL
 376         hwdep->oss_type = -1;
 377 #endif
 378         if ((err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops)) < 0) {
 379                 snd_hwdep_free(hwdep);
 380                 return err;
 381         }
 382         init_waitqueue_head(&hwdep->open_wait);
 383         init_MUTEX(&hwdep->open_mutex);
 384         *rhwdep = hwdep;
 385         return 0;
 386 }
 387
 388 static int snd_hwdep_free(snd_hwdep_t *hwdep)
 389 {
 390         snd_assert(hwdep != NULL, return -ENXIO);
 391         if (hwdep->private_free)
 392                 hwdep->private_free(hwdep);
 393         kfree(hwdep);
 394         return 0;
 395 }
 396
 397 static int snd_hwdep_dev_free(snd_device_t *device)
 398 {
 399         snd_hwdep_t *hwdep = device->device_data;
 400         return snd_hwdep_free(hwdep);
 401 }
 402
 403 static int snd_hwdep_dev_register(snd_device_t *device)
 404 {
 405         snd_hwdep_t *hwdep = device->device_data;
 406         int idx, err;
 407         char name[32];
 408
 409         down(&register_mutex);
 410         idx = (hwdep->card->number * SNDRV_MINOR_HWDEPS) + hwdep->device;
 411         if (snd_hwdep_devices[idx]) {
 412                 up(&register_mutex);
 413                 return -EBUSY;
 414         }
 415         snd_hwdep_devices[idx] = hwdep;
 416         sprintf(name, "hwC%iD%i", hwdep->card->number, hwdep->device);
 417         if ((err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
 418                                        hwdep->card, hwdep->device,
 419                                        &snd_hwdep_reg, name)) < 0) {
 420                 snd_printk(KERN_ERR "unable to register hardware dependent device %i:%i\n",
 421                            hwdep->card->number, hwdep->device);
 422                 snd_hwdep_devices[idx] = NULL;
 423                 up(&register_mutex);
 424                 return err;
 425         }
 426 #ifdef CONFIG_SND_OSSEMUL
 427         hwdep->ossreg = 0;
 428         if (hwdep->oss_type >= 0) {
 429                 if ((hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM) && (hwdep->device != 0)) {
 430                         snd_printk (KERN_WARNING "only hwdep device 0 can be registered as OSS direct FM device!\n");
 431                 } else {
 432                         if (snd_register_oss_device(hwdep->oss_type,
 433                                                     hwdep->card, hwdep->device,
 434                                                     &snd_hwdep_reg, hwdep->oss_dev) < 0) {
 435                                 snd_printk(KERN_ERR "unable to register OSS compatibility device %i:%i\n",
 436                                            hwdep->card->number, hwdep->device);
 437                         } else
 438                                 hwdep->ossreg = 1;
 439                 }
 440         }
 441 #endif
 442         up(&register_mutex);
 443         return 0;
 444 }
 445
 446 static int snd_hwdep_dev_unregister(snd_device_t *device)
 447 {
 448         snd_hwdep_t *hwdep = device->device_data;
 449         int idx;
 450
 451         snd_assert(hwdep != NULL, return -ENXIO);
 452         down(&register_mutex);
 453         idx = (hwdep->card->number * SNDRV_MINOR_HWDEPS) + hwdep->device;
 454         if (snd_hwdep_devices[idx] != hwdep) {
 455                 up(&register_mutex);
 456                 return -EINVAL;
 457         }
 458 #ifdef CONFIG_SND_OSSEMUL
 459         if (hwdep->ossreg)
 460                 snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
 461 #endif
 462         snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
 463         snd_hwdep_devices[idx] = NULL;
 464         up(&register_mutex);
 465         return snd_hwdep_free(hwdep);
 466 }
 467
 468 /*
 469  *  Info interface
 470  */
 471
 472 static void snd_hwdep_proc_read(snd_info_entry_t *entry,
 473                                 snd_info_buffer_t * buffer)
 474 {
 475         int idx;
 476         snd_hwdep_t *hwdep;
 477
 478         down(&register_mutex);
 479         for (idx = 0; idx < SNDRV_CARDS * SNDRV_MINOR_HWDEPS; idx++) {
 480                 hwdep = snd_hwdep_devices[idx];
 481                 if (hwdep == NULL)
 482                         continue;
 483                 snd_iprintf(buffer, "%02i-%02i: %s\n",
 484                                         idx / SNDRV_MINOR_HWDEPS,
 485                                         idx % SNDRV_MINOR_HWDEPS,
 486                                         hwdep->name);
 487         }
 488         up(&register_mutex);
 489 }
 490
 491 /*
 492  *  ENTRY functions
 493  */
 494
 495 static snd_info_entry_t *snd_hwdep_proc_entry = NULL;
 496
 497 static int __init alsa_hwdep_init(void)
 498 {
 499         snd_info_entry_t *entry;
 500
 501         memset(snd_hwdep_devices, 0, sizeof(snd_hwdep_devices));
 502         if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
 503                 entry->c.text.read_size = 512;
 504                 entry->c.text.read = snd_hwdep_proc_read;
 505                 if (snd_info_register(entry) < 0) {
 506                         snd_info_free_entry(entry);
 507                         entry = NULL;
 508                 }
 509         }
 510         snd_hwdep_proc_entry = entry;
 511         snd_ctl_register_ioctl(snd_hwdep_control_ioctl);
 512         return 0;
 513 }
 514
 515 static void __exit alsa_hwdep_exit(void)
 516 {
 517         snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl);
 518         if (snd_hwdep_proc_entry) {
 519                 snd_info_unregister(snd_hwdep_proc_entry);
 520                 snd_hwdep_proc_entry = NULL;
 521         }
 522 }
 523
 524 module_init(alsa_hwdep_init)
 525 module_exit(alsa_hwdep_exit)
 526
 527 EXPORT_SYMBOL(snd_hwdep_new);