ASoC: bdw-rt5677: add channel constraint

BDW boards using this machine driver supports only stereo capture and
playback. Implement a constraint to enforce it.

Signed-off-by: Brent Lu <brent.lu@intel.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/1588007614-25061-2-git-send-email-brent.lu@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/intel/boards/bdw-rt5677.c b/sound/soc/intel/boards/bdw-rt5677.c
index cc41a348295ec3c6b37dd1ff47bfc7aae4932d5b..5f96d7ac0a226e2d98e6c6567692c378c33133b9 100644 (file)
--- a/sound/soc/intel/boards/bdw-rt5677.c
+++ b/sound/soc/intel/boards/bdw-rt5677.c
@@ -222,6 +222,31 @@ static int bdw_rt5677_rtd_init(struct snd_soc_pcm_runtime *rtd)
 }
 #endif
 
+static const unsigned int channels[] = {
+       2,
+};
+
+static const struct snd_pcm_hw_constraint_list constraints_channels = {
+       .count = ARRAY_SIZE(channels),
+       .list = channels,
+       .mask = 0,
+};
+
+static int bdw_rt5677_fe_startup(struct snd_pcm_substream *substream)
+{
+       struct snd_pcm_runtime *runtime = substream->runtime;
+
+       /* Board supports stereo configuration only */
+       runtime->hw.channels_max = 2;
+       return snd_pcm_hw_constraint_list(runtime, 0,
+                                         SNDRV_PCM_HW_PARAM_CHANNELS,
+                                         &constraints_channels);
+}
+
+static const struct snd_soc_ops bdw_rt5677_fe_ops = {
+       .startup = bdw_rt5677_fe_startup,
+};
+
 static int bdw_rt5677_init(struct snd_soc_pcm_runtime *rtd)
 {
        struct bdw_rt5677_priv *bdw_rt5677 =
@@ -321,6 +346,7 @@ static struct snd_soc_dai_link bdw_rt5677_dais[] = {
                },
                .dpcm_capture = 1,
                .dpcm_playback = 1,
+               .ops = &bdw_rt5677_fe_ops,
                SND_SOC_DAILINK_REG(fe, dummy, platform),
        },