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Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0312-Revert-bcm2835-interpolate-audio-delay.patch')
-rw-r--r--target/linux/brcm2708/patches-4.4/0312-Revert-bcm2835-interpolate-audio-delay.patch70
1 files changed, 70 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0312-Revert-bcm2835-interpolate-audio-delay.patch b/target/linux/brcm2708/patches-4.4/0312-Revert-bcm2835-interpolate-audio-delay.patch
new file mode 100644
index 0000000000..a972170c19
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.4/0312-Revert-bcm2835-interpolate-audio-delay.patch
@@ -0,0 +1,70 @@
+From 65978c7586dc8fe403a3a3bebf40de881b8d2741 Mon Sep 17 00:00:00 2001
+From: popcornmix <popcornmix@gmail.com>
+Date: Fri, 29 Apr 2016 17:27:37 +0100
+Subject: [PATCH 312/423] Revert "bcm2835: interpolate audio delay"
+
+This reverts commit 83eca613d0eddd2c8299f114b8fe573ccaffdefc.
+---
+ sound/arm/bcm2835-pcm.c | 12 +-----------
+ sound/arm/bcm2835.h | 1 -
+ 2 files changed, 1 insertion(+), 12 deletions(-)
+
+--- a/sound/arm/bcm2835-pcm.c
++++ b/sound/arm/bcm2835-pcm.c
+@@ -25,7 +25,7 @@
+ /* hardware definition */
+ static struct snd_pcm_hardware snd_bcm2835_playback_hw = {
+ .info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
+- SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID | SNDRV_PCM_INFO_BATCH),
++ SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID),
+ .formats = SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE,
+ .rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
+ .rate_min = 8000,
+@@ -99,8 +99,6 @@ static irqreturn_t bcm2835_playback_fifo
+ alsa_stream->pos %= alsa_stream->buffer_size;
+ }
+
+- alsa_stream->interpolate_start = ktime_get_ns();
+-
+ if (alsa_stream->substream) {
+ if (new_period)
+ snd_pcm_period_elapsed(alsa_stream->substream);
+@@ -401,7 +399,6 @@ static int snd_bcm2835_pcm_prepare(struc
+ alsa_stream->buffer_size = snd_pcm_lib_buffer_bytes(substream);
+ alsa_stream->period_size = snd_pcm_lib_period_bytes(substream);
+ alsa_stream->pos = 0;
+- alsa_stream->interpolate_start = ktime_get_ns();
+
+ audio_debug("buffer_size=%d, period_size=%d pos=%d frame_bits=%d\n",
+ alsa_stream->buffer_size, alsa_stream->period_size,
+@@ -498,7 +495,6 @@ snd_bcm2835_pcm_pointer(struct snd_pcm_s
+ {
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ bcm2835_alsa_stream_t *alsa_stream = runtime->private_data;
+- u64 now = ktime_get_ns();
+
+ audio_info(" .. IN\n");
+
+@@ -507,12 +503,6 @@ snd_bcm2835_pcm_pointer(struct snd_pcm_s
+ frames_to_bytes(runtime, runtime->control->appl_ptr),
+ alsa_stream->pos);
+
+- /* Give userspace better delay reporting by interpolating between GPU
+- * notifications, assuming audio speed is close enough to the clock
+- * used for ktime */
+- if (alsa_stream->interpolate_start && alsa_stream->interpolate_start < now)
+- runtime->delay = -(int)div_u64((now - alsa_stream->interpolate_start) * runtime->rate, 1000000000);
+-
+ audio_info(" .. OUT\n");
+ return snd_pcm_indirect_playback_pointer(substream,
+ &alsa_stream->pcm_indirect,
+--- a/sound/arm/bcm2835.h
++++ b/sound/arm/bcm2835.h
+@@ -137,7 +137,6 @@ typedef struct bcm2835_alsa_stream {
+ unsigned int pos;
+ unsigned int buffer_size;
+ unsigned int period_size;
+- u64 interpolate_start;
+
+ uint32_t enable_fifo_irq;
+ irq_handler_t fifo_irq_handler;