kernel/sound/core/sound_oss.c

   1 /*
   2  *  Advanced Linux Sound Architecture
   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 #ifdef CONFIG_SND_OSSEMUL
  23
  24 #if !IS_ENABLED(CONFIG_SOUND)
  25 #error "Enable the OSS soundcore multiplexer (CONFIG_SOUND) in the kernel."
  26 #endif
  27
  28 #include <linux/init.h>
  29 #include <linux/export.h>
  30 #include <linux/slab.h>
  31 #include <linux/time.h>
  32 #include <sound/core.h>
  33 #include <sound/minors.h>
  34 #include <sound/info.h>
  35 #include <linux/sound.h>
  36 #include <linux/mutex.h>
  37
  38 #define SNDRV_OSS_MINORS 256
  39
  40 static struct snd_minor *snd_oss_minors[SNDRV_OSS_MINORS];
  41 static DEFINE_MUTEX(sound_oss_mutex);
  42
  43 /* NOTE: This function increments the refcount of the associated card like
  44  * snd_lookup_minor_data(); the caller must call snd_card_unref() appropriately
  45  */
  46 void *snd_lookup_oss_minor_data(unsigned int minor, int type)
  47 {
  48         struct snd_minor *mreg;
  49         void *private_data;
  50
  51         if (minor >= ARRAY_SIZE(snd_oss_minors))
  52                 return NULL;
  53         mutex_lock(&sound_oss_mutex);
  54         mreg = snd_oss_minors[minor];
  55         if (mreg && mreg->type == type) {
  56                 private_data = mreg->private_data;
  57                 if (private_data && mreg->card_ptr)
  58                         get_device(&mreg->card_ptr->card_dev);
  59         } else
  60                 private_data = NULL;
  61         mutex_unlock(&sound_oss_mutex);
  62         return private_data;
  63 }
  64
  65 EXPORT_SYMBOL(snd_lookup_oss_minor_data);
  66
  67 static int snd_oss_kernel_minor(int type, struct snd_card *card, int dev)
  68 {
  69         int minor;
  70
  71         switch (type) {
  72         case SNDRV_OSS_DEVICE_TYPE_MIXER:
  73                 if (snd_BUG_ON(!card || dev < 0 || dev > 1))
  74                         return -EINVAL;
  75                 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIXER1 : SNDRV_MINOR_OSS_MIXER));
  76                 break;
  77         case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:
  78                 minor = SNDRV_MINOR_OSS_SEQUENCER;
  79                 break;
  80         case SNDRV_OSS_DEVICE_TYPE_MUSIC:
  81                 minor = SNDRV_MINOR_OSS_MUSIC;
  82                 break;
  83         case SNDRV_OSS_DEVICE_TYPE_PCM:
  84                 if (snd_BUG_ON(!card || dev < 0 || dev > 1))
  85                         return -EINVAL;
  86                 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_PCM1 : SNDRV_MINOR_OSS_PCM));
  87                 break;
  88         case SNDRV_OSS_DEVICE_TYPE_MIDI:
  89                 if (snd_BUG_ON(!card || dev < 0 || dev > 1))
  90                         return -EINVAL;
  91                 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIDI1 : SNDRV_MINOR_OSS_MIDI));
  92                 break;
  93         case SNDRV_OSS_DEVICE_TYPE_DMFM:
  94                 minor = SNDRV_MINOR_OSS(card->number, SNDRV_MINOR_OSS_DMFM);
  95                 break;
  96         case SNDRV_OSS_DEVICE_TYPE_SNDSTAT:
  97                 minor = SNDRV_MINOR_OSS_SNDSTAT;
  98                 break;
  99         default:
 100                 return -EINVAL;
 101         }
 102         if (minor < 0 || minor >= SNDRV_OSS_MINORS)
 103                 return -EINVAL;
 104         return minor;
 105 }
 106
 107 int snd_register_oss_device(int type, struct snd_card *card, int dev,
 108                             const struct file_operations *f_ops, void *private_data)
 109 {
 110         int minor = snd_oss_kernel_minor(type, card, dev);
 111         int minor_unit;
 112         struct snd_minor *preg;
 113         int cidx = SNDRV_MINOR_OSS_CARD(minor);
 114         int track2 = -1;
 115         int register1 = -1, register2 = -1;
 116         struct device *carddev = snd_card_get_device_link(card);
 117
 118         if (card && card->number >= SNDRV_MINOR_OSS_DEVICES)
 119                 return 0; /* ignore silently */
 120         if (minor < 0)
 121                 return minor;
 122         preg = kmalloc(sizeof(struct snd_minor), GFP_KERNEL);
 123         if (preg == NULL)
 124                 return -ENOMEM;
 125         preg->type = type;
 126         preg->card = card ? card->number : -1;
 127         preg->device = dev;
 128         preg->f_ops = f_ops;
 129         preg->private_data = private_data;
 130         preg->card_ptr = card;
 131         mutex_lock(&sound_oss_mutex);
 132         snd_oss_minors[minor] = preg;
 133         minor_unit = SNDRV_MINOR_OSS_DEVICE(minor);
 134         switch (minor_unit) {
 135         case SNDRV_MINOR_OSS_PCM:
 136                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO);
 137                 break;
 138         case SNDRV_MINOR_OSS_MIDI:
 139                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI);
 140                 break;
 141         case SNDRV_MINOR_OSS_MIDI1:
 142                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1);
 143                 break;
 144         }
 145         register1 = register_sound_special_device(f_ops, minor, carddev);
 146         if (register1 != minor)
 147                 goto __end;
 148         if (track2 >= 0) {
 149                 register2 = register_sound_special_device(f_ops, track2,
 150                                                           carddev);
 151                 if (register2 != track2)
 152                         goto __end;
 153                 snd_oss_minors[track2] = preg;
 154         }
 155         mutex_unlock(&sound_oss_mutex);
 156         return 0;
 157
 158       __end:
 159         if (register2 >= 0)
 160                 unregister_sound_special(register2);
 161         if (register1 >= 0)
 162                 unregister_sound_special(register1);
 163         snd_oss_minors[minor] = NULL;
 164         mutex_unlock(&sound_oss_mutex);
 165         kfree(preg);
 166         return -EBUSY;
 167 }
 168
 169 EXPORT_SYMBOL(snd_register_oss_device);
 170
 171 int snd_unregister_oss_device(int type, struct snd_card *card, int dev)
 172 {
 173         int minor = snd_oss_kernel_minor(type, card, dev);
 174         int cidx = SNDRV_MINOR_OSS_CARD(minor);
 175         int track2 = -1;
 176         struct snd_minor *mptr;
 177
 178         if (card && card->number >= SNDRV_MINOR_OSS_DEVICES)
 179                 return 0;
 180         if (minor < 0)
 181                 return minor;
 182         mutex_lock(&sound_oss_mutex);
 183         mptr = snd_oss_minors[minor];
 184         if (mptr == NULL) {
 185                 mutex_unlock(&sound_oss_mutex);
 186                 return -ENOENT;
 187         }
 188         unregister_sound_special(minor);
 189         switch (SNDRV_MINOR_OSS_DEVICE(minor)) {
 190         case SNDRV_MINOR_OSS_PCM:
 191                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO);
 192                 break;
 193         case SNDRV_MINOR_OSS_MIDI:
 194                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI);
 195                 break;
 196         case SNDRV_MINOR_OSS_MIDI1:
 197                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1);
 198                 break;
 199         }
 200         if (track2 >= 0) {
 201                 unregister_sound_special(track2);
 202                 snd_oss_minors[track2] = NULL;
 203         }
 204         snd_oss_minors[minor] = NULL;
 205         mutex_unlock(&sound_oss_mutex);
 206         kfree(mptr);
 207         return 0;
 208 }
 209
 210 EXPORT_SYMBOL(snd_unregister_oss_device);
 211
 212 /*
 213  *  INFO PART
 214  */
 215
 216 #ifdef CONFIG_PROC_FS
 217
 218 static struct snd_info_entry *snd_minor_info_oss_entry;
 219
 220 static const char *snd_oss_device_type_name(int type)
 221 {
 222         switch (type) {
 223         case SNDRV_OSS_DEVICE_TYPE_MIXER:
 224                 return "mixer";
 225         case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:
 226         case SNDRV_OSS_DEVICE_TYPE_MUSIC:
 227                 return "sequencer";
 228         case SNDRV_OSS_DEVICE_TYPE_PCM:
 229                 return "digital audio";
 230         case SNDRV_OSS_DEVICE_TYPE_MIDI:
 231                 return "raw midi";
 232         case SNDRV_OSS_DEVICE_TYPE_DMFM:
 233                 return "hardware dependent";
 234         default:
 235                 return "?";
 236         }
 237 }
 238
 239 static void snd_minor_info_oss_read(struct snd_info_entry *entry,
 240                                     struct snd_info_buffer *buffer)
 241 {
 242         int minor;
 243         struct snd_minor *mptr;
 244
 245         mutex_lock(&sound_oss_mutex);
 246         for (minor = 0; minor < SNDRV_OSS_MINORS; ++minor) {
 247                 if (!(mptr = snd_oss_minors[minor]))
 248                         continue;
 249                 if (mptr->card >= 0)
 250                         snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", minor,
 251                                     mptr->card, mptr->device,
 252                                     snd_oss_device_type_name(mptr->type));
 253                 else
 254                         snd_iprintf(buffer, "%3i:       : %s\n", minor,
 255                                     snd_oss_device_type_name(mptr->type));
 256         }
 257         mutex_unlock(&sound_oss_mutex);
 258 }
 259
 260
 261 int __init snd_minor_info_oss_init(void)
 262 {
 263         struct snd_info_entry *entry;
 264
 265         entry = snd_info_create_module_entry(THIS_MODULE, "devices", snd_oss_root);
 266         if (entry) {
 267                 entry->c.text.read = snd_minor_info_oss_read;
 268                 if (snd_info_register(entry) < 0) {
 269                         snd_info_free_entry(entry);
 270                         entry = NULL;
 271                 }
 272         }
 273         snd_minor_info_oss_entry = entry;
 274         return 0;
 275 }
 276
 277 int __exit snd_minor_info_oss_done(void)
 278 {
 279         snd_info_free_entry(snd_minor_info_oss_entry);
 280         return 0;
 281 }
 282 #endif /* CONFIG_PROC_FS */
 283
 284 #endif /* CONFIG_SND_OSSEMUL */