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From 96588b9ccaddd69a832a07e2e3f2f3299e6d6c3a Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Tue, 4 Sep 2018 17:58:30 +0200
Subject: [PATCH] staging: bcm2835-audio: Clean up mutex locks
commit ce4bb1aa271a97047b80ac917a5d91b54925913b upstream.
snd-bcm2835 driver takes the lock with mutex_lock_interruptible() in
all places, which don't make sense. Replace them with the simple
mutex_lock().
Also taking a mutex lock right after creating it for each PCM object
is nonsense, too. It cannot be racy at that point. We can get rid of
it.
Last but not least, initializing chip->audio_mutex at each place is
error-prone. Initialize properly at creating the chip object in
snd_bcm2835_create() instead.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
.../vc04_services/bcm2835-audio/bcm2835-ctl.c | 18 +++----
.../vc04_services/bcm2835-audio/bcm2835-pcm.c | 33 ++-----------
.../bcm2835-audio/bcm2835-vchiq.c | 47 ++++---------------
.../vc04_services/bcm2835-audio/bcm2835.c | 1 +
4 files changed, 20 insertions(+), 79 deletions(-)
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-ctl.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-ctl.c
@@ -77,8 +77,7 @@ static int snd_bcm2835_ctl_get(struct sn
{
struct bcm2835_chip *chip = snd_kcontrol_chip(kcontrol);
- if (mutex_lock_interruptible(&chip->audio_mutex))
- return -EINTR;
+ mutex_lock(&chip->audio_mutex);
BUG_ON(!chip && !(chip->avail_substreams & AVAIL_SUBSTREAMS_MASK));
@@ -99,8 +98,7 @@ static int snd_bcm2835_ctl_put(struct sn
struct bcm2835_chip *chip = snd_kcontrol_chip(kcontrol);
int changed = 0;
- if (mutex_lock_interruptible(&chip->audio_mutex))
- return -EINTR;
+ mutex_lock(&chip->audio_mutex);
if (kcontrol->private_value == PCM_PLAYBACK_VOLUME) {
audio_info("Volume change attempted.. volume = %d new_volume = %d\n", chip->volume, (int)ucontrol->value.integer.value[0]);
@@ -187,8 +185,7 @@ static int snd_bcm2835_spdif_default_get
struct bcm2835_chip *chip = snd_kcontrol_chip(kcontrol);
int i;
- if (mutex_lock_interruptible(&chip->audio_mutex))
- return -EINTR;
+ mutex_lock(&chip->audio_mutex);
for (i = 0; i < 4; i++)
ucontrol->value.iec958.status[i] =
@@ -205,8 +202,7 @@ static int snd_bcm2835_spdif_default_put
unsigned int val = 0;
int i, change;
- if (mutex_lock_interruptible(&chip->audio_mutex))
- return -EINTR;
+ mutex_lock(&chip->audio_mutex);
for (i = 0; i < 4; i++)
val |= (unsigned int)ucontrol->value.iec958.status[i] << (i * 8);
@@ -251,8 +247,7 @@ static int snd_bcm2835_spdif_stream_get(
struct bcm2835_chip *chip = snd_kcontrol_chip(kcontrol);
int i;
- if (mutex_lock_interruptible(&chip->audio_mutex))
- return -EINTR;
+ mutex_lock(&chip->audio_mutex);
for (i = 0; i < 4; i++)
ucontrol->value.iec958.status[i] =
@@ -269,8 +264,7 @@ static int snd_bcm2835_spdif_stream_put(
unsigned int val = 0;
int i, change;
- if (mutex_lock_interruptible(&chip->audio_mutex))
- return -EINTR;
+ mutex_lock(&chip->audio_mutex);
for (i = 0; i < 4; i++)
val |= (unsigned int)ucontrol->value.iec958.status[i] << (i * 8);
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
@@ -99,10 +99,7 @@ static int snd_bcm2835_playback_open_gen
int idx;
int err;
- if (mutex_lock_interruptible(&chip->audio_mutex)) {
- audio_error("Interrupted whilst waiting for lock\n");
- return -EINTR;
- }
+ mutex_lock(&chip->audio_mutex);
audio_info("Alsa open (%d)\n", substream->number);
idx = substream->number;
@@ -194,10 +191,7 @@ static int snd_bcm2835_playback_close(st
struct bcm2835_alsa_stream *alsa_stream;
chip = snd_pcm_substream_chip(substream);
- if (mutex_lock_interruptible(&chip->audio_mutex)) {
- audio_error("Interrupted whilst waiting for lock\n");
- return -EINTR;
- }
+ mutex_lock(&chip->audio_mutex);
runtime = substream->runtime;
alsa_stream = runtime->private_data;
@@ -274,8 +268,7 @@ static int snd_bcm2835_pcm_prepare(struc
int channels;
int err;
- if (mutex_lock_interruptible(&chip->audio_mutex))
- return -EINTR;
+ mutex_lock(&chip->audio_mutex);
/* notify the vchiq that it should enter spdif passthrough mode by
* setting channels=0 (see
@@ -449,14 +442,9 @@ int snd_bcm2835_new_pcm(struct bcm2835_c
struct snd_pcm *pcm;
int err;
- mutex_init(&chip->audio_mutex);
- if (mutex_lock_interruptible(&chip->audio_mutex)) {
- audio_error("Interrupted whilst waiting for lock\n");
- return -EINTR;
- }
err = snd_pcm_new(chip->card, "bcm2835 ALSA", 0, numchannels, 0, &pcm);
if (err < 0)
- goto out;
+ return err;
pcm->private_data = chip;
strcpy(pcm->name, "bcm2835 ALSA");
chip->pcm = pcm;
@@ -474,9 +462,6 @@ int snd_bcm2835_new_pcm(struct bcm2835_c
snd_bcm2835_playback_hw.buffer_bytes_max,
snd_bcm2835_playback_hw.buffer_bytes_max);
-out:
- mutex_unlock(&chip->audio_mutex);
-
return 0;
}
@@ -485,13 +470,9 @@ int snd_bcm2835_new_spdif_pcm(struct bcm
struct snd_pcm *pcm;
int err;
- if (mutex_lock_interruptible(&chip->audio_mutex)) {
- audio_error("Interrupted whilst waiting for lock\n");
- return -EINTR;
- }
err = snd_pcm_new(chip->card, "bcm2835 ALSA", 1, 1, 0, &pcm);
if (err < 0)
- goto out;
+ return err;
pcm->private_data = chip;
strcpy(pcm->name, "bcm2835 IEC958/HDMI");
@@ -504,8 +485,6 @@ int snd_bcm2835_new_spdif_pcm(struct bcm
snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
snd_dma_continuous_data(GFP_KERNEL),
snd_bcm2835_playback_spdif_hw.buffer_bytes_max, snd_bcm2835_playback_spdif_hw.buffer_bytes_max);
-out:
- mutex_unlock(&chip->audio_mutex);
return 0;
}
@@ -518,8 +497,6 @@ int snd_bcm2835_new_simple_pcm(struct bc
struct snd_pcm *pcm;
int err;
- mutex_init(&chip->audio_mutex);
-
err = snd_pcm_new(chip->card, name, 0, numchannels,
0, &pcm);
if (err)
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c
@@ -319,11 +319,7 @@ static int vc_vchi_audio_deinit(struct b
}
LOG_DBG(" .. about to lock (%d)\n", instance->num_connections);
- if (mutex_lock_interruptible(&instance->vchi_mutex)) {
- LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",
- instance->num_connections);
- return -EINTR;
- }
+ mutex_lock(&instance->vchi_mutex);
/* Close all VCHI service connections */
for (i = 0; i < instance->num_connections; i++) {
@@ -434,11 +430,7 @@ int bcm2835_audio_open(struct bcm2835_al
instance = alsa_stream->instance;
LOG_DBG(" instance (%p)\n", instance);
- if (mutex_lock_interruptible(&instance->vchi_mutex)) {
- LOG_DBG("Interrupted whilst waiting for lock on (%d)\n", instance->num_connections);
- ret = -EINTR;
- goto free_wq;
- }
+ mutex_lock(&instance->vchi_mutex);
vchi_service_use(instance->vchi_handle[0]);
m.type = VC_AUDIO_MSG_TYPE_OPEN;
@@ -479,11 +471,7 @@ static int bcm2835_audio_set_ctls_chan(s
LOG_INFO(" Setting ALSA dest(%d), volume(%d)\n",
chip->dest, chip->volume);
- if (mutex_lock_interruptible(&instance->vchi_mutex)) {
- LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",
- instance->num_connections);
- return -EINTR;
- }
+ mutex_lock(&instance->vchi_mutex);
vchi_service_use(instance->vchi_handle[0]);
instance->result = -1;
@@ -569,10 +557,7 @@ int bcm2835_audio_set_params(struct bcm2
return -EINVAL;
}
- if (mutex_lock_interruptible(&instance->vchi_mutex)) {
- LOG_DBG("Interrupted whilst waiting for lock on (%d)\n", instance->num_connections);
- return -EINTR;
- }
+ mutex_lock(&instance->vchi_mutex);
vchi_service_use(instance->vchi_handle[0]);
instance->result = -1;
@@ -629,11 +614,7 @@ static int bcm2835_audio_start_worker(st
int status;
int ret;
- if (mutex_lock_interruptible(&instance->vchi_mutex)) {
- LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",
- instance->num_connections);
- return -EINTR;
- }
+ mutex_lock(&instance->vchi_mutex);
vchi_service_use(instance->vchi_handle[0]);
m.type = VC_AUDIO_MSG_TYPE_START;
@@ -665,11 +646,7 @@ static int bcm2835_audio_stop_worker(str
int status;
int ret;
- if (mutex_lock_interruptible(&instance->vchi_mutex)) {
- LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",
- instance->num_connections);
- return -EINTR;
- }
+ mutex_lock(&instance->vchi_mutex);
vchi_service_use(instance->vchi_handle[0]);
m.type = VC_AUDIO_MSG_TYPE_STOP;
@@ -704,11 +681,7 @@ int bcm2835_audio_close(struct bcm2835_a
my_workqueue_quit(alsa_stream);
- if (mutex_lock_interruptible(&instance->vchi_mutex)) {
- LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",
- instance->num_connections);
- return -EINTR;
- }
+ mutex_lock(&instance->vchi_mutex);
vchi_service_use(instance->vchi_handle[0]);
m.type = VC_AUDIO_MSG_TYPE_CLOSE;
@@ -761,11 +734,7 @@ static int bcm2835_audio_write_worker(st
LOG_INFO(" Writing %d bytes from %p\n", count, src);
- if (mutex_lock_interruptible(&instance->vchi_mutex)) {
- LOG_DBG("Interrupted whilst waiting for lock on (%d)\n",
- instance->num_connections);
- return -EINTR;
- }
+ mutex_lock(&instance->vchi_mutex);
vchi_service_use(instance->vchi_handle[0]);
if (instance->peer_version == 0 &&
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835.c
@@ -149,6 +149,7 @@ static int snd_bcm2835_create(struct snd
return -ENOMEM;
chip->card = card;
+ mutex_init(&chip->audio_mutex);
chip->vchi_ctx = devres_find(card->dev->parent,
bcm2835_devm_free_vchi_ctx, NULL, NULL);
|
