[PATCH v5 4/5] ASoC: qdsp6: q6apm-dai: set 10 ms period and buffer alignment.

srinivas.kandagatla
2025-03-14T17:48:39Z

From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

DSP expects the periods to be aligned to fragment sizes, currently
setting up to hw constriants on periods bytes is not going to work
correctly as we can endup with periods sizes aligned to 32 bytes however
not aligned to fragment size.

Update the constriants to use fragment size, and also set at step of
10ms for period size to accommodate DSP requirements of 10ms latency.

Fixes: 9b4fe0f1cd79 ("ASoC: qdsp6: audioreach: add q6apm-dai support")
Cc: stable@vger.kernel.org
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
---
sound/soc/qcom/qdsp6/q6apm-dai.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/sound/soc/qcom/qdsp6/q6apm-dai.c b/sound/soc/qcom/qdsp6/q6apm-dai.c
index 90cb24947f31..180ff24041bf 100644
--- a/sound/soc/qcom/qdsp6/q6apm-dai.c
+++ b/sound/soc/qcom/qdsp6/q6apm-dai.c
@@ -385,13 +385,14 @@ static int q6apm_dai_open(struct snd_soc_component *component,
}
}

- ret = snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 32);
+ /* setup 10ms latency to accommodate DSP restrictions */
+ ret = snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 480);
if (ret < 0) {
dev_err(dev, "constraint for period bytes step ret = %d\n", ret);
goto err;
}

- ret = snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 32);
+ ret = snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, 480);
if (ret < 0) {
dev_err(dev, "constraint for buffer bytes step ret = %d\n", ret);
goto err;
--
2.39.5