ASoC: fsl_sai: Reset FIFOs after disabling TE/RE

SAI will not clear their FIFOs after disabling TE/RE. Therfore, the driver
should take care the task so as not to let useless data remain in the FIFO.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

sound/soc/fsl/fsl_sai.c

@@ -371,10 +371,13 @@ static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd,
 
 		/* Check if the opposite FRDE is also disabled */
 		if (!(tx ? rcsr & FSL_SAI_CSR_FRDE : tcsr & FSL_SAI_CSR_FRDE)) {
+			/* Disable both directions and reset their FIFOs */
 			regmap_update_bits(sai->regmap, FSL_SAI_TCSR,
-					   FSL_SAI_CSR_TERE, 0);
+					   FSL_SAI_CSR_TERE | FSL_SAI_CSR_FR,
+					   FSL_SAI_CSR_FR);
 			regmap_update_bits(sai->regmap, FSL_SAI_RCSR,
-					   FSL_SAI_CSR_TERE, 0);
+					   FSL_SAI_CSR_TERE | FSL_SAI_CSR_FR,
+					   FSL_SAI_CSR_FR);
 		}
 		break;
 	default: