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>

diff --git a/include/sound/control.h b/include/sound/control.h
index 042613938a1db4fdf1f5b0b3d5b373d90307887d..75f3054023f71182b6cf4ab89491c65180cb6292 100644 (file)
--- a/include/sound/control.h
+++ b/include/sound/control.h
@@ -93,12 +93,17 @@ struct snd_kctl_event {
 
 struct pid;
 
+enum {
+       SND_CTL_SUBDEV_PCM,
+       SND_CTL_SUBDEV_RAWMIDI,
+       SND_CTL_SUBDEV_ITEMS,
+};
+
 struct snd_ctl_file {
        struct list_head list;          /* list of all control files */
        struct snd_card *card;
        struct pid *pid;
-       int prefer_pcm_subdevice;
-       int prefer_rawmidi_subdevice;
+       int preferred_subdevice[SND_CTL_SUBDEV_ITEMS];
        wait_queue_head_t change_sleep;
        spinlock_t read_lock;
        struct fasync_struct *fasync;
@@ -138,6 +143,8 @@ int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn);
 #define snd_ctl_unregister_ioctl_compat(fcn)
 #endif
 
+int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type);
+
 static inline unsigned int snd_ctl_get_ioffnum(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
 {
        return id->numid - kctl->id.numid;

diff --git a/sound/core/control.c b/sound/core/control.c
index bb96a467e88d080ff693766f77b36b4dc1a02b01..cd246a0bcd5528e7302c2c0ea69e63482da177c1 100644 (file)
--- 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
  */

diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index dba5180e5b8072e220e35a38330c24c41ec3bf47..1b7c473720fa46c8999975c5890c4298aa0d0863 100644 (file)
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -161,7 +161,7 @@ static int snd_pcm_control_ioctl(struct snd_card *card,
                        
                        if (get_user(val, (int __user *)arg))
                                return -EFAULT;
-                       control->prefer_pcm_subdevice = val;
+                       control->preferred_subdevice[SND_CTL_SUBDEV_PCM] = val;
                        return 0;
                }
        }
@@ -901,9 +901,8 @@ int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
        struct snd_pcm_str * pstr;
        struct snd_pcm_substream *substream;
        struct snd_pcm_runtime *runtime;
-       struct snd_ctl_file *kctl;
        struct snd_card *card;
-       int prefer_subdevice = -1;
+       int prefer_subdevice;
        size_t size;
 
        if (snd_BUG_ON(!pcm || !rsubstream))
@@ -914,15 +913,7 @@ int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
                return -ENODEV;
 
        card = pcm->card;
-       read_lock(&card->ctl_files_rwlock);
-       list_for_each_entry(kctl, &card->ctl_files, list) {
-               if (kctl->pid == task_pid(current)) {
-                       prefer_subdevice = kctl->prefer_pcm_subdevice;
-                       if (prefer_subdevice != -1)
-                               break;
-               }
-       }
-       read_unlock(&card->ctl_files_rwlock);
+       prefer_subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_PCM);
 
        switch (stream) {
        case SNDRV_PCM_STREAM_PLAYBACK:

diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index 6fc71a4c8a5177c63094333093de18a70b3159ac..be18162c380f15257e6a1a6c77b7f7ae90e13559 100644 (file)
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -369,7 +369,6 @@ static int snd_rawmidi_open(struct inode *inode, struct file *file)
        struct snd_rawmidi *rmidi;
        struct snd_rawmidi_file *rawmidi_file = NULL;
        wait_queue_t wait;
-       struct snd_ctl_file *kctl;
 
        if ((file->f_flags & O_APPEND) && !(file->f_flags & O_NONBLOCK)) 
                return -EINVAL;         /* invalid combination */
@@ -413,16 +412,7 @@ static int snd_rawmidi_open(struct inode *inode, struct file *file)
        init_waitqueue_entry(&wait, current);
        add_wait_queue(&rmidi->open_wait, &wait);
        while (1) {
-               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->prefer_rawmidi_subdevice;
-                               if (subdevice != -1)
-                                       break;
-                       }
-               }
-               read_unlock(&card->ctl_files_rwlock);
+               subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_RAWMIDI);
                err = rawmidi_open_priv(rmidi, subdevice, fflags, rawmidi_file);
                if (err >= 0)
                        break;
@@ -862,7 +852,7 @@ static int snd_rawmidi_control_ioctl(struct snd_card *card,
                
                if (get_user(val, (int __user *)argp))
                        return -EFAULT;
-               control->prefer_rawmidi_subdevice = val;
+               control->preferred_subdevice[SND_CTL_SUBDEV_RAWMIDI] = val;
                return 0;
        }
        case SNDRV_CTL_IOCTL_RAWMIDI_INFO: