ALSA: usx2y: Don't peep the card internal object
Avoid traversing the device object list of the card instance just for
checking the PCM streams. The driver's private object already
contains the array of substream pointers, so it can be simply looked
through. The card internal may be restructured in future, thus better
not to rely on it.
Also, this fixes the possible deadlocks in PCM mutex. Instead of
taking multiple PCM mutexes, just take the common mutex in all
places. Along with it, rename prepare_mutex as pcm_mutex.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/usx2y/usx2yhwdeppcm.c b/sound/usb/usx2y/usx2yhwdeppcm.c
index 814d0e8..90766a9 100644
--- a/sound/usb/usx2y/usx2yhwdeppcm.c
+++ b/sound/usb/usx2y/usx2yhwdeppcm.c
@@ -358,7 +358,7 @@
struct snd_pcm_runtime *runtime = substream->runtime;
struct snd_usX2Y_substream *subs = runtime->private_data,
*cap_subs2 = subs->usX2Y->subs[SNDRV_PCM_STREAM_CAPTURE + 2];
- mutex_lock(&subs->usX2Y->prepare_mutex);
+ mutex_lock(&subs->usX2Y->pcm_mutex);
snd_printdd("snd_usX2Y_usbpcm_hw_free(%p)\n", substream);
if (SNDRV_PCM_STREAM_PLAYBACK == substream->stream) {
@@ -387,7 +387,7 @@
usX2Y_usbpcm_urbs_release(cap_subs2);
}
}
- mutex_unlock(&subs->usX2Y->prepare_mutex);
+ mutex_unlock(&subs->usX2Y->pcm_mutex);
return snd_pcm_lib_free_pages(substream);
}
@@ -493,7 +493,7 @@
memset(usX2Y->hwdep_pcm_shm, 0, sizeof(struct snd_usX2Y_hwdep_pcm_shm));
}
- mutex_lock(&usX2Y->prepare_mutex);
+ mutex_lock(&usX2Y->pcm_mutex);
usX2Y_subs_prepare(subs);
// Start hardware streams
// SyncStream first....
@@ -534,7 +534,7 @@
usX2Y->hwdep_pcm_shm->capture_iso_start = -1;
up_prepare_mutex:
- mutex_unlock(&usX2Y->prepare_mutex);
+ mutex_unlock(&usX2Y->pcm_mutex);
return err;
}
@@ -600,59 +600,30 @@
};
-static int usX2Y_pcms_lock_check(struct snd_card *card)
+static int usX2Y_pcms_busy_check(struct snd_card *card)
{
- struct list_head *list;
- struct snd_device *dev;
- struct snd_pcm *pcm;
- int err = 0;
- list_for_each(list, &card->devices) {
- dev = snd_device(list);
- if (dev->type != SNDRV_DEV_PCM)
- continue;
- pcm = dev->device_data;
- mutex_lock(&pcm->open_mutex);
+ struct usX2Ydev *dev = usX2Y(card);
+ int i;
+
+ for (i = 0; i < dev->pcm_devs * 2; i++) {
+ struct snd_usX2Y_substream *subs = dev->subs[i];
+ if (subs && subs->pcm_substream &&
+ SUBSTREAM_BUSY(subs->pcm_substream))
+ return -EBUSY;
}
- list_for_each(list, &card->devices) {
- int s;
- dev = snd_device(list);
- if (dev->type != SNDRV_DEV_PCM)
- continue;
- pcm = dev->device_data;
- for (s = 0; s < 2; ++s) {
- struct snd_pcm_substream *substream;
- substream = pcm->streams[s].substream;
- if (substream && SUBSTREAM_BUSY(substream))
- err = -EBUSY;
- }
- }
- return err;
+ return 0;
}
-
-static void usX2Y_pcms_unlock(struct snd_card *card)
-{
- struct list_head *list;
- struct snd_device *dev;
- struct snd_pcm *pcm;
- list_for_each(list, &card->devices) {
- dev = snd_device(list);
- if (dev->type != SNDRV_DEV_PCM)
- continue;
- pcm = dev->device_data;
- mutex_unlock(&pcm->open_mutex);
- }
-}
-
-
static int snd_usX2Y_hwdep_pcm_open(struct snd_hwdep *hw, struct file *file)
{
- // we need to be the first
struct snd_card *card = hw->card;
- int err = usX2Y_pcms_lock_check(card);
- if (0 == err)
+ int err;
+
+ mutex_lock(&usX2Y(card)->pcm_mutex);
+ err = usX2Y_pcms_busy_check(card);
+ if (!err)
usX2Y(card)->chip_status |= USX2Y_STAT_CHIP_MMAP_PCM_URBS;
- usX2Y_pcms_unlock(card);
+ mutex_unlock(&usX2Y(card)->pcm_mutex);
return err;
}
@@ -660,10 +631,13 @@
static int snd_usX2Y_hwdep_pcm_release(struct snd_hwdep *hw, struct file *file)
{
struct snd_card *card = hw->card;
- int err = usX2Y_pcms_lock_check(card);
- if (0 == err)
+ int err;
+
+ mutex_lock(&usX2Y(card)->pcm_mutex);
+ err = usX2Y_pcms_busy_check(card);
+ if (!err)
usX2Y(hw->card)->chip_status &= ~USX2Y_STAT_CHIP_MMAP_PCM_URBS;
- usX2Y_pcms_unlock(card);
+ mutex_unlock(&usX2Y(card)->pcm_mutex);
return err;
}