ASoC: Intel: Add FE rate & channel constraints for bxt-rt298

We support stereo 48Khz audio, so add these as constraints
for this card

Signed-off-by: Senthilnathan Veppur <senthilnathanx.veppur@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/boards/bxt_rt298.c

@@ -220,6 +220,40 @@ static struct snd_soc_ops broxton_dmic_ops = {
 	.startup = broxton_dmic_startup,
 };
 
+static unsigned int channels[] = {
+	2,
+};
+
+static struct snd_pcm_hw_constraint_list constraints_channels = {
+	.count = ARRAY_SIZE(channels),
+	.list = channels,
+	.mask = 0,
+};
+
+static int bxt_fe_startup(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+
+	/*
+	 * on this platform for PCM device we support:
+	 *      48Khz
+	 *      stereo
+	 */
+
+	runtime->hw.channels_max = 2;
+	snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
+				&constraints_channels);
+
+	snd_pcm_hw_constraint_list(runtime, 0,
+				SNDRV_PCM_HW_PARAM_RATE, &constraints_rates);
+
+	return 0;
+}
+
+static const struct snd_soc_ops broxton_rt286_fe_ops = {
+	.startup = bxt_fe_startup,
+};
+
 /* broxton digital audio interface glue - connects codec <--> CPU */
 static struct snd_soc_dai_link broxton_rt298_dais[] = {
 	/* Front End DAI links */
@@ -235,6 +269,7 @@ static struct snd_soc_dai_link broxton_rt298_dais[] = {
 		.codec_dai_name = "snd-soc-dummy-dai",
 		.trigger = {SND_SOC_DPCM_TRIGGER_POST, SND_SOC_DPCM_TRIGGER_POST},
 		.dpcm_playback = 1,
+		.ops = &broxton_rt286_fe_ops,
 	},
 	[BXT_DPCM_AUDIO_CP]
 	{
@@ -248,6 +283,7 @@ static struct snd_soc_dai_link broxton_rt298_dais[] = {
 		.codec_dai_name = "snd-soc-dummy-dai",
 		.trigger = {SND_SOC_DPCM_TRIGGER_POST, SND_SOC_DPCM_TRIGGER_POST},
 		.dpcm_capture = 1,
+		.ops = &broxton_rt286_fe_ops,
 	},
 	[BXT_DPCM_AUDIO_REF_CP]
 	{