[PATCH 16/29] staging: bcm2835-audio: Drop superfluous mutex lock during prepare

Takashi Iwai
2018-09-04T16:00:30Z

The chip->audio_mutex is used basically for protecting the opened
stream assignment, and the prepare callback is irrelevant with it.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
index 1f9c940f1cc3..9659c25b9f9d 100644
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
@@ -218,8 +218,6 @@ static int snd_bcm2835_pcm_prepare(struct snd_pcm_substream *substream)
int channels;
int err;

- mutex_lock(&chip->audio_mutex);
-
/* notify the vchiq that it should enter spdif passthrough mode by
* setting channels=0 (see
* https://github.com/raspberrypi/linux/issues/528)
@@ -233,7 +231,7 @@ static int snd_bcm2835_pcm_prepare(struct snd_pcm_substream *substream)
runtime->rate,
snd_pcm_format_width(runtime->format));
if (err < 0)
- goto out;
+ return err;

memset(&alsa_stream->pcm_indirect, 0, sizeof(alsa_stream->pcm_indirect));

@@ -246,9 +244,7 @@ static int snd_bcm2835_pcm_prepare(struct snd_pcm_substream *substream)
alsa_stream->pos = 0;
alsa_stream->draining = false;

- out:
- mutex_unlock(&chip->audio_mutex);
- return err;
+ return 0;
}

static void snd_bcm2835_pcm_transfer(struct snd_pcm_substream *substream,
--
2.18.0