Permit ALSA to run without hardware interrupts from the audio interface. Instead, ALSA will use a kernel timer to decide when to check the buffer state, resulting in a lighter workload for the CPU.
Signed-off-by: Russell King rmk+kernel@arm.linux.org.uk --- sound/soc/kirkwood/kirkwood-dma.c | 11 ++++++----- sound/soc/kirkwood/kirkwood-i2s.c | 9 ++++++--- 2 files changed, 12 insertions(+), 8 deletions(-)
diff --git a/sound/soc/kirkwood/kirkwood-dma.c b/sound/soc/kirkwood/kirkwood-dma.c index aac22fccdcdc..4cf2245950d7 100644 --- a/sound/soc/kirkwood/kirkwood-dma.c +++ b/sound/soc/kirkwood/kirkwood-dma.c @@ -28,11 +28,12 @@ static struct kirkwood_dma_data *kirkwood_priv(struct snd_pcm_substream *subs) }
static struct snd_pcm_hardware kirkwood_dma_snd_hw = { - .info = (SNDRV_PCM_INFO_INTERLEAVED | - SNDRV_PCM_INFO_MMAP | - SNDRV_PCM_INFO_MMAP_VALID | - SNDRV_PCM_INFO_BLOCK_TRANSFER | - SNDRV_PCM_INFO_PAUSE), + .info = SNDRV_PCM_INFO_INTERLEAVED | + SNDRV_PCM_INFO_MMAP | + SNDRV_PCM_INFO_MMAP_VALID | + SNDRV_PCM_INFO_BLOCK_TRANSFER | + SNDRV_PCM_INFO_PAUSE | + SNDRV_PCM_INFO_NO_PERIOD_WAKEUP, .buffer_bytes_max = KIRKWOOD_SND_MAX_BUFFER_BYTES, .period_bytes_min = KIRKWOOD_SND_MIN_PERIOD_BYTES, .period_bytes_max = KIRKWOOD_SND_MAX_PERIOD_BYTES, diff --git a/sound/soc/kirkwood/kirkwood-i2s.c b/sound/soc/kirkwood/kirkwood-i2s.c index e98650c01eba..0704cd6d2314 100644 --- a/sound/soc/kirkwood/kirkwood-i2s.c +++ b/sound/soc/kirkwood/kirkwood-i2s.c @@ -234,6 +234,7 @@ static unsigned kirkwood_i2s_play_mute(unsigned ctl) static int kirkwood_i2s_play_trigger(struct snd_pcm_substream *substream, int cmd, struct snd_soc_dai *dai) { + struct snd_pcm_runtime *runtime = substream->runtime; struct kirkwood_dma_data *priv = snd_soc_dai_get_drvdata(dai); uint32_t ctl, value;
@@ -271,9 +272,11 @@ static int kirkwood_i2s_play_trigger(struct snd_pcm_substream *substream, writel(value, priv->io + KIRKWOOD_PLAYCTL);
/* enable interrupts */ - value = readl(priv->io + KIRKWOOD_INT_MASK); - value |= KIRKWOOD_INT_CAUSE_PLAY_BYTES; - writel(value, priv->io + KIRKWOOD_INT_MASK); + if (!runtime->no_period_wakeup) { + value = readl(priv->io + KIRKWOOD_INT_MASK); + value |= KIRKWOOD_INT_CAUSE_PLAY_BYTES; + writel(value, priv->io + KIRKWOOD_INT_MASK); + }
/* enable playback */ writel(ctl, priv->io + KIRKWOOD_PLAYCTL);