[PATCH 04/29] staging: bcm2835-audio: Remove redundant substream mask checks

From: Takashi Iwai
Date: Tue Sep 04 2018 - 12:00:47 EST


The avail_substreams bit mask is checked for the possible racy
accesses, but this cannot happen in practice; i.e. the assignment and
the check are superfluous.

Let's rip them off.

Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
---
.../vc04_services/bcm2835-audio/bcm2835-ctl.c | 2 --
.../vc04_services/bcm2835-audio/bcm2835-pcm.c | 8 --------
.../vc04_services/bcm2835-audio/bcm2835-vchiq.c | 17 +++++++----------
.../vc04_services/bcm2835-audio/bcm2835.c | 5 +----
.../vc04_services/bcm2835-audio/bcm2835.h | 2 --
5 files changed, 8 insertions(+), 26 deletions(-)

diff --git a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-ctl.c b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-ctl.c
index 1c5a87580978..d2f0f609f737 100644
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-ctl.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-ctl.c
@@ -64,8 +64,6 @@ static int snd_bcm2835_ctl_get(struct snd_kcontrol *kcontrol,

mutex_lock(&chip->audio_mutex);

- BUG_ON(!chip && !(chip->avail_substreams & AVAIL_SUBSTREAMS_MASK));
-
if (kcontrol->private_value == PCM_PLAYBACK_VOLUME)
ucontrol->value.integer.value[0] = chip2alsa(chip->volume);
else if (kcontrol->private_value == PCM_PLAYBACK_MUTE)
diff --git a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
index f2d8b17d0cfe..0be185350f33 100644
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-pcm.c
@@ -118,14 +118,6 @@ static int snd_bcm2835_playback_open_generic(
goto out;
}

- /* Check if we are ready */
- if (!(chip->avail_substreams & (1 << idx))) {
- /* We are not ready yet */
- audio_error("substream(%d) device is not ready yet\n", idx);
- err = -EAGAIN;
- goto out;
- }
-
alsa_stream = kzalloc(sizeof(*alsa_stream), GFP_KERNEL);
if (!alsa_stream) {
err = -ENOMEM;
diff --git a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c
index bec361aff4fe..942a38942c29 100644
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c
@@ -523,16 +523,13 @@ int bcm2835_audio_set_ctls(struct bcm2835_chip *chip)

/* change ctls for all substreams */
for (i = 0; i < MAX_SUBSTREAMS; i++) {
- if (chip->avail_substreams & (1 << i)) {
- if (!chip->alsa_stream[i]) {
- LOG_DBG(" No ALSA stream available?! %i:%p (%x)\n", i, chip->alsa_stream[i], chip->avail_substreams);
- ret = 0;
- } else if (bcm2835_audio_set_ctls_chan(chip->alsa_stream[i], chip) != 0) {
- LOG_ERR("Couldn't set the controls for stream %d\n", i);
- ret = -1;
- } else {
- LOG_DBG(" Controls set for stream %d\n", i);
- }
+ if (!chip->alsa_stream[i])
+ continue;
+ if (bcm2835_audio_set_ctls_chan(chip->alsa_stream[i], chip) != 0) {
+ LOG_ERR("Couldn't set the controls for stream %d\n", i);
+ ret = -1;
+ } else {
+ LOG_DBG(" Controls set for stream %d\n", i);
}
}
return ret;
diff --git a/drivers/staging/vc04_services/bcm2835-audio/bcm2835.c b/drivers/staging/vc04_services/bcm2835-audio/bcm2835.c
index fa04f6bc9858..6876a5eadc07 100644
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835.c
@@ -280,7 +280,7 @@ static int snd_add_child_device(struct device *device,
struct snd_card *card;
struct device *child;
struct bcm2835_chip *chip;
- int err, i;
+ int err;

child = snd_create_device(device, &audio_driver->driver,
audio_driver->driver.name);
@@ -325,9 +325,6 @@ static int snd_add_child_device(struct device *device,
return err;
}

- for (i = 0; i < numchans; i++)
- chip->avail_substreams |= (1 << i);
-
err = snd_card_register(card);
if (err) {
dev_err(child, "Failed to register card, error %d\n", err);
diff --git a/drivers/staging/vc04_services/bcm2835-audio/bcm2835.h b/drivers/staging/vc04_services/bcm2835-audio/bcm2835.h
index 5dc427240a1d..c0e7df4914ed 100644
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835.h
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835.h
@@ -98,8 +98,6 @@ struct bcm2835_chip {
struct snd_card *card;
struct snd_pcm *pcm;
struct snd_pcm *pcm_spdif;
- /* Bitmat for valid reg_base and irq numbers */
- unsigned int avail_substreams;
struct device *dev;
struct bcm2835_alsa_stream *alsa_stream[MAX_SUBSTREAMS];

--
2.18.0