diff options
Diffstat (limited to 'sound/core/sound.c')
| -rw-r--r-- | sound/core/sound.c | 46 |
1 files changed, 40 insertions, 6 deletions
diff --git a/sound/core/sound.c b/sound/core/sound.c index a509f49..1e5eca5 100644 --- a/sound/core/sound.c +++ b/sound/core/sound.c @@ -60,7 +60,6 @@ MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR); int snd_ecards_limit; static struct snd_minor *snd_minors[SNDRV_OS_MINORS]; - static DECLARE_MUTEX(sound_mutex); extern struct class *sound_class; @@ -107,6 +106,31 @@ static void snd_request_other(int minor) #endif /* request_module support */ +/** + * snd_lookup_minor_data - get user data of a registered device + * @minor: the minor number + * @type: device type (SNDRV_DEVICE_TYPE_XXX) + * + * Checks that a minor device with the specified type is registered, and returns + * its user data pointer. + */ +void *snd_lookup_minor_data(unsigned int minor, int type) +{ + struct snd_minor *mreg; + void *private_data; + + if (minor > ARRAY_SIZE(snd_minors)) + return NULL; + down(&sound_mutex); + mreg = snd_minors[minor]; + if (mreg && mreg->type == type) + private_data = mreg->private_data; + else + private_data = NULL; + up(&sound_mutex); + return private_data; +} + static int snd_open(struct inode *inode, struct file *file) { int minor = iminor(inode); @@ -183,6 +207,7 @@ static int snd_kernel_minor(int type, struct snd_card *card, int dev) * @card: the card instance * @dev: the device index * @f_ops: the file operations + * @private_data: user pointer for f_ops->open() * @name: the device file name * * Registers an ALSA device file for the given card. @@ -191,7 +216,8 @@ static int snd_kernel_minor(int type, struct snd_card *card, int dev) * Retrurns zero if successful, or a negative error code on failure. */ int snd_register_device(int type, struct snd_card *card, int dev, - struct file_operations *f_ops, const char *name) + struct file_operations *f_ops, void *private_data, + const char *name) { int minor = snd_kernel_minor(type, card, dev); struct snd_minor *preg; @@ -207,6 +233,7 @@ int snd_register_device(int type, struct snd_card *card, int dev, preg->card = card ? card->number : -1; preg->device = dev; preg->f_ops = f_ops; + preg->private_data = private_data; strcpy(preg->name, name); down(&sound_mutex); if (snd_minors[minor]) { @@ -238,13 +265,18 @@ int snd_register_device(int type, struct snd_card *card, int dev, */ int snd_unregister_device(int type, struct snd_card *card, int dev) { - int minor = snd_kernel_minor(type, card, dev); + int cardnum, minor; struct snd_minor *mptr; - if (minor < 0) - return minor; + cardnum = card ? card->number : -1; down(&sound_mutex); - if ((mptr = snd_minors[minor]) == NULL) { + for (minor = 0; minor < ARRAY_SIZE(snd_minors); ++minor) + if ((mptr = snd_minors[minor]) != NULL && + mptr->type == type && + mptr->card == cardnum && + mptr->device == dev) + break; + if (minor == ARRAY_SIZE(snd_minors)) { up(&sound_mutex); return -EINVAL; } @@ -392,9 +424,11 @@ EXPORT_SYMBOL(snd_request_card); #endif EXPORT_SYMBOL(snd_register_device); EXPORT_SYMBOL(snd_unregister_device); +EXPORT_SYMBOL(snd_lookup_minor_data); #if defined(CONFIG_SND_OSSEMUL) EXPORT_SYMBOL(snd_register_oss_device); EXPORT_SYMBOL(snd_unregister_oss_device); +EXPORT_SYMBOL(snd_lookup_oss_minor_data); #endif /* memory.c */ EXPORT_SYMBOL(copy_to_user_fromio); |