diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0130-bcm2835-access-controls-under-the-audio-mutex.patch')
-rw-r--r-- | target/linux/brcm2708/patches-4.4/0130-bcm2835-access-controls-under-the-audio-mutex.patch | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0130-bcm2835-access-controls-under-the-audio-mutex.patch b/target/linux/brcm2708/patches-4.4/0130-bcm2835-access-controls-under-the-audio-mutex.patch new file mode 100644 index 0000000000..ce1c05c62e --- /dev/null +++ b/target/linux/brcm2708/patches-4.4/0130-bcm2835-access-controls-under-the-audio-mutex.patch @@ -0,0 +1,237 @@ +From 16a8daf3e66584f5c1bd3b113675d3fc3b44adc1 Mon Sep 17 00:00:00 2001 +From: wm4 <wm4@nowhere> +Date: Wed, 13 Jan 2016 19:43:35 +0100 +Subject: [PATCH 130/381] bcm2835: access controls under the audio mutex + +I don't think the ALSA framework provides any kind of automatic +synchronization within the control callbacks. We most likely need +to ensure this manually, so add locking around all access to shared +mutable data. In particular, bcm2835_audio_set_ctls() should +probably always be called under our own audio lock. +--- + sound/arm/bcm2835-ctl.c | 74 +++++++++++++++++++++++++++++++++++++++++-------- + sound/arm/bcm2835-pcm.c | 4 +++ + 2 files changed, 66 insertions(+), 12 deletions(-) + +--- a/sound/arm/bcm2835-ctl.c ++++ b/sound/arm/bcm2835-ctl.c +@@ -94,6 +94,9 @@ 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; ++ + BUG_ON(!chip && !(chip->avail_substreams & AVAIL_SUBSTREAMS_MASK)); + + if (kcontrol->private_value == PCM_PLAYBACK_VOLUME) +@@ -103,6 +106,7 @@ static int snd_bcm2835_ctl_get(struct sn + else if (kcontrol->private_value == PCM_PLAYBACK_DEVICE) + ucontrol->value.integer.value[0] = chip->dest; + ++ mutex_unlock(&chip->audio_mutex); + return 0; + } + +@@ -112,11 +116,15 @@ 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; ++ + 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]); + if (chip->mute == CTRL_VOL_MUTE) { + /* changed = toggle_mute(chip, CTRL_VOL_UNMUTE); */ +- return 1; /* should return 0 to signify no change but the mixer takes this as the opposite sign (no idea why) */ ++ changed = 1; /* should return 0 to signify no change but the mixer takes this as the opposite sign (no idea why) */ ++ goto unlock; + } + if (changed + || (ucontrol->value.integer.value[0] != chip2alsa(chip->volume))) { +@@ -142,6 +150,8 @@ static int snd_bcm2835_ctl_put(struct sn + printk(KERN_ERR "Failed to set ALSA controls..\n"); + } + ++unlock: ++ mutex_unlock(&chip->audio_mutex); + return changed; + } + +@@ -198,10 +208,14 @@ 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; ++ + for (i = 0; i < 4; i++) + ucontrol->value.iec958.status[i] = + (chip->spdif_status >> (i * 8)) && 0xff; + ++ mutex_unlock(&chip->audio_mutex); + return 0; + } + +@@ -212,12 +226,16 @@ static int snd_bcm2835_spdif_default_put + unsigned int val = 0; + int i, change; + ++ if (mutex_lock_interruptible(&chip->audio_mutex)) ++ return -EINTR; ++ + for (i = 0; i < 4; i++) + val |= (unsigned int)ucontrol->value.iec958.status[i] << (i * 8); + + change = val != chip->spdif_status; + chip->spdif_status = val; + ++ mutex_unlock(&chip->audio_mutex); + return change; + } + +@@ -253,9 +271,14 @@ 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; ++ + for (i = 0; i < 4; i++) + ucontrol->value.iec958.status[i] = + (chip->spdif_status >> (i * 8)) & 0xff; ++ ++ mutex_unlock(&chip->audio_mutex); + return 0; + } + +@@ -266,11 +289,15 @@ static int snd_bcm2835_spdif_stream_put( + unsigned int val = 0; + int i, change; + ++ if (mutex_lock_interruptible(&chip->audio_mutex)) ++ return -EINTR; ++ + for (i = 0; i < 4; i++) + val |= (unsigned int)ucontrol->value.iec958.status[i] << (i * 8); + change = val != chip->spdif_status; + chip->spdif_status = val; + ++ mutex_unlock(&chip->audio_mutex); + return change; + } + +@@ -454,11 +481,17 @@ static int snd_bcm2835_chmap_ctl_get(str + unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id); + struct snd_pcm_substream *substream = snd_pcm_chmap_substream(info, idx); + struct cea_channel_speaker_allocation *ch = NULL; ++ int res = 0; + int cur = 0; + int i; + +- if (!substream || !substream->runtime) +- return -ENODEV; ++ if (mutex_lock_interruptible(&chip->audio_mutex)) ++ return -EINTR; ++ ++ if (!substream || !substream->runtime) { ++ res = -ENODEV; ++ goto unlock; ++ } + + for (i = 0; i < ARRAY_SIZE(channel_allocations); i++) { + if (channel_allocations[i].ca_index == chip->cea_chmap) +@@ -476,7 +509,10 @@ static int snd_bcm2835_chmap_ctl_get(str + } + while (cur < 8) + ucontrol->value.integer.value[cur++] = SNDRV_CHMAP_NA; +- return 0; ++ ++unlock: ++ mutex_unlock(&chip->audio_mutex); ++ return res; + } + + static int snd_bcm2835_chmap_ctl_put(struct snd_kcontrol *kcontrol, +@@ -487,10 +523,16 @@ static int snd_bcm2835_chmap_ctl_put(str + unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id); + struct snd_pcm_substream *substream = snd_pcm_chmap_substream(info, idx); + int i, prepared = 0, cea_chmap = -1; ++ int res = 0; + int remap[8]; + +- if (!substream || !substream->runtime) +- return -ENODEV; ++ if (mutex_lock_interruptible(&chip->audio_mutex)) ++ return -EINTR; ++ ++ if (!substream || !substream->runtime) { ++ res = -ENODEV; ++ goto unlock; ++ } + + switch (substream->runtime->status->state) { + case SNDRV_PCM_STATE_OPEN: +@@ -500,7 +542,8 @@ static int snd_bcm2835_chmap_ctl_put(str + prepared = 1; + break; + default: +- return -EBUSY; ++ res = -EBUSY; ++ goto unlock; + } + + for (i = 0; i < ARRAY_SIZE(channel_allocations); i++) { +@@ -538,19 +581,26 @@ static int snd_bcm2835_chmap_ctl_put(str + } + } + +- if (cea_chmap < 0) +- return -EINVAL; ++ if (cea_chmap < 0) { ++ res = -EINVAL; ++ goto unlock; ++ } + + /* don't change the layout if another substream is active */ +- if (chip->opened != (1 << substream->number) && chip->cea_chmap != cea_chmap) +- return -EBUSY; /* unsure whether this is a good error code */ ++ if (chip->opened != (1 << substream->number) && chip->cea_chmap != cea_chmap) { ++ res = -EBUSY; /* unsure whether this is a good error code */ ++ goto unlock; ++ } + + chip->cea_chmap = cea_chmap; + for (i = 0; i < 8; i++) + chip->map_channels[i] = remap[i]; + if (prepared) + snd_bcm2835_pcm_prepare_again(substream); +- return 0; ++ ++unlock: ++ mutex_unlock(&chip->audio_mutex); ++ return res; + } + + static int snd_bcm2835_add_chmap_ctl(bcm2835_chip_t * chip) +--- a/sound/arm/bcm2835-pcm.c ++++ b/sound/arm/bcm2835-pcm.c +@@ -379,6 +379,9 @@ static int snd_bcm2835_pcm_prepare(struc + + audio_info(" .. IN\n"); + ++ if (mutex_lock_interruptible(&chip->audio_mutex)) ++ return -EINTR; ++ + snd_bcm2835_pcm_prepare_again(substream); + + bcm2835_audio_setup(alsa_stream); +@@ -401,6 +404,7 @@ static int snd_bcm2835_pcm_prepare(struc + alsa_stream->buffer_size, alsa_stream->period_size, + alsa_stream->pos, runtime->frame_bits); + ++ mutex_unlock(&chip->audio_mutex); + audio_info(" .. OUT\n"); + return 0; + } |