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