ASoC: SOF: add a helper to get topology configured bclk

Add helper function sof_dai_ssp_bclk() to get the BCLK frequency
configured by topology.
Reviewed-by: Bard Liao <bard.liao@intel.com>
Signed-off-by: Brent Lu <brent.lu@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20210625205042.65181-4-pierre-louis.bossart@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

include/sound/sof.h

@@ -101,5 +101,6 @@ struct sof_dev_desc {
 };
 
 int sof_dai_get_mclk(struct snd_soc_pcm_runtime *rtd);
+int sof_dai_get_bclk(struct snd_soc_pcm_runtime *rtd);
 
 #endif

sound/soc/sof/sof-audio.c

@@ -433,11 +433,10 @@ struct snd_sof_dai *snd_sof_find_dai(struct snd_soc_component *scomp,
 	return NULL;
 }
 
-/*
- * Helper to get SSP MCLK from a pcm_runtime.
- * Return 0 if not exist.
- */
-int sof_dai_get_mclk(struct snd_soc_pcm_runtime *rtd)
+#define SOF_DAI_CLK_INTEL_SSP_MCLK	0
+#define SOF_DAI_CLK_INTEL_SSP_BCLK	1
+
+static int sof_dai_get_clk(struct snd_soc_pcm_runtime *rtd, int clk_type)
 {
 	struct snd_soc_component *component =
 		snd_soc_rtdcom_lookup(rtd, SOF_AUDIO_PCM_DRV_NAME);
@@ -450,16 +449,45 @@ int sof_dai_get_mclk(struct snd_soc_pcm_runtime *rtd)
 
 	switch (dai->dai_config->type) {
 	case SOF_DAI_INTEL_SSP:
+		switch (clk_type) {
+		case SOF_DAI_CLK_INTEL_SSP_MCLK:
 			return dai->dai_config->ssp.mclk_rate;
+		case SOF_DAI_CLK_INTEL_SSP_BCLK:
+			return dai->dai_config->ssp.bclk_rate;
+		default:
+			dev_err(rtd->dev, "fail to get SSP clk %d rate\n",
+				clk_type);
+			return -EINVAL;
+		}
+		break;
 	default:
 		/* not yet implemented for platforms other than the above */
-		dev_err(rtd->dev, "mclk for dai_config->type %d not supported yet!\n",
+		dev_err(rtd->dev, "DAI type %d not supported yet!\n",
 			dai->dai_config->type);
 		return -EINVAL;
 	}
 }
+
+/*
+ * Helper to get SSP MCLK from a pcm_runtime.
+ * Return 0 if not exist.
+ */
+int sof_dai_get_mclk(struct snd_soc_pcm_runtime *rtd)
+{
+	return sof_dai_get_clk(rtd, SOF_DAI_CLK_INTEL_SSP_MCLK);
+}
 EXPORT_SYMBOL(sof_dai_get_mclk);
 
+/*
+ * Helper to get SSP BCLK from a pcm_runtime.
+ * Return 0 if not exist.
+ */
+int sof_dai_get_bclk(struct snd_soc_pcm_runtime *rtd)
+{
+	return sof_dai_get_clk(rtd, SOF_DAI_CLK_INTEL_SSP_BCLK);
+}
+EXPORT_SYMBOL(sof_dai_get_bclk);
+
 /*
  * SOF Driver enumeration.
  */