diff options
| author | Takashi Iwai <tiwai@suse.de> | 2014-02-19 14:30:29 +0100 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2015-02-02 14:21:21 +0100 |
| commit | 23c18d4bfd73ee24070849faf98b3ab01263a3c4 (patch) | |
| tree | 944e0e24bd847fdbbddd8baf5ab0976c0fdcfa81 /sound/core/control.c | |
| parent | 92b7952da8279189aad352efbf9f2e7001de9524 (diff) | |
| download | linux-23c18d4bfd73ee24070849faf98b3ab01263a3c4.tar.gz linux-23c18d4bfd73ee24070849faf98b3ab01263a3c4.tar.bz2 linux-23c18d4bfd73ee24070849faf98b3ab01263a3c4.zip | |
ALSA: control: Provide a helper to look for the preferred subdevice
Instead of open-coding the search over the control file loop, provide
a helper function for the preferred subdevice assigned to the current
process.
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/core/control.c')
| -rw-r--r-- | sound/core/control.c | 27 |
1 files changed, 24 insertions, 3 deletions
diff --git a/sound/core/control.c b/sound/core/control.c index bb96a467e88d..cd246a0bcd55 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -50,7 +50,7 @@ static int snd_ctl_open(struct inode *inode, struct file *file) unsigned long flags; struct snd_card *card; struct snd_ctl_file *ctl; - int err; + int i, err; err = nonseekable_open(inode, file); if (err < 0) @@ -79,8 +79,8 @@ static int snd_ctl_open(struct inode *inode, struct file *file) init_waitqueue_head(&ctl->change_sleep); spin_lock_init(&ctl->read_lock); ctl->card = card; - ctl->prefer_pcm_subdevice = -1; - ctl->prefer_rawmidi_subdevice = -1; + for (i = 0; i < SND_CTL_SUBDEV_ITEMS; i++) + ctl->preferred_subdevice[i] = -1; ctl->pid = get_pid(task_pid(current)); file->private_data = ctl; write_lock_irqsave(&card->ctl_files_rwlock, flags); @@ -1607,6 +1607,27 @@ static int snd_ctl_fasync(int fd, struct file * file, int on) return fasync_helper(fd, file, on, &ctl->fasync); } +/* return the preferred subdevice number if already assigned; + * otherwise return -1 + */ +int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type) +{ + struct snd_ctl_file *kctl; + int subdevice = -1; + + read_lock(&card->ctl_files_rwlock); + list_for_each_entry(kctl, &card->ctl_files, list) { + if (kctl->pid == task_pid(current)) { + subdevice = kctl->preferred_subdevice[type]; + if (subdevice != -1) + break; + } + } + read_unlock(&card->ctl_files_rwlock); + return subdevice; +} +EXPORT_SYMBOL_GPL(snd_ctl_get_preferred_subdevice); + /* * ioctl32 compat */ |