[PATCH v3 2/2] ASoC: Intel: Add period size constraint on strago board

[Brent Lu <brent.lu@intel.com>]

From: Yu-Hsuan Hsu <yuhsuan@chromium.org>

The CRAS server does not set the period size in hw_param so ALSA will
calculate a value for period size which is based on the buffer size
and other parameters. The value may not always be aligned with Atom's
dsp design so a constraint is added to make sure the board always has
a good value.

Cyan uses chtmax98090 and others(banon, celes, edgar, kefka...) use
rt5650.

Signed-off-by: Yu-Hsuan Hsu <yuhsuan@chromium.org>
Signed-off-by: Brent Lu <brent.lu@intel.com>
---
 sound/soc/intel/boards/cht_bsw_max98090_ti.c | 14 +++++++++++++-
 sound/soc/intel/boards/cht_bsw_rt5645.c      | 14 +++++++++++++-
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/sound/soc/intel/boards/cht_bsw_max98090_ti.c b/sound/soc/intel/boards/cht_bsw_max98090_ti.c
index 835e9bd..bf67254 100644
--- a/sound/soc/intel/boards/cht_bsw_max98090_ti.c
+++ b/sound/soc/intel/boards/cht_bsw_max98090_ti.c
@@ -283,8 +283,20 @@ static int cht_codec_fixup(struct snd_soc_pcm_runtime *rtd,
 
 static int cht_aif1_startup(struct snd_pcm_substream *substream)
 {
-	return snd_pcm_hw_constraint_single(substream->runtime,
+	int err;
+
+	/* Set period size to 240 to align with Atom design */
+	err = snd_pcm_hw_constraint_minmax(substream->runtime,
+			SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 240, 240);
+	if (err < 0)
+		return err;
+
+	err = snd_pcm_hw_constraint_single(substream->runtime,
 			SNDRV_PCM_HW_PARAM_RATE, 48000);
+	if (err < 0)
+		return err;
+
+	return 0;
 }
 
 static int cht_max98090_headset_init(struct snd_soc_component *component)
diff --git a/sound/soc/intel/boards/cht_bsw_rt5645.c b/sound/soc/intel/boards/cht_bsw_rt5645.c
index b53c024..6e62f0d 100644
--- a/sound/soc/intel/boards/cht_bsw_rt5645.c
+++ b/sound/soc/intel/boards/cht_bsw_rt5645.c
@@ -414,8 +414,20 @@ static int cht_codec_fixup(struct snd_soc_pcm_runtime *rtd,
 
 static int cht_aif1_startup(struct snd_pcm_substream *substream)
 {
-	return snd_pcm_hw_constraint_single(substream->runtime,
+	int err;
+
+	/* Set period size to 240 to align with Atom design */
+	err = snd_pcm_hw_constraint_minmax(substream->runtime,
+			SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 240, 240);
+	if (err < 0)
+		return err;
+
+	err = snd_pcm_hw_constraint_single(substream->runtime,
 			SNDRV_PCM_HW_PARAM_RATE, 48000);
+	if (err < 0)
+		return err;
+
+	return 0;
 }
 
 static const struct snd_soc_ops cht_aif1_ops = {
-- 
2.7.4