[PATCH] ASoC: imx-card: Fix DSD/PDM mclk frequency

Shengjiu Wang shengjiu.wang at nxp.com
Wed Jul 6 11:42:55 CEST 2022


The DSD/PDM rate not only DSD64/128/256/512, which are the
multiple rate of 44.1kHz,  but also support the multiple
rate of 8kHz, so can't force all mclk frequency to be
22579200Hz, need to assign the frequency according to
rate.

Fixes: aa736700f42f ("ASoC: imx-card: Add imx-card machine driver")
Signed-off-by: Shengjiu Wang <shengjiu.wang at nxp.com>
---
 sound/soc/fsl/imx-card.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/sound/soc/fsl/imx-card.c b/sound/soc/fsl/imx-card.c
index 1797d777b1b8..ccc4194dc5e7 100644
--- a/sound/soc/fsl/imx-card.c
+++ b/sound/soc/fsl/imx-card.c
@@ -17,6 +17,9 @@
 
 #include "fsl_sai.h"
 
+#define IMX_CARD_MCLK_22P5792MHZ  22579200
+#define IMX_CARD_MCLK_24P576MHZ   24576000
+
 enum codec_type {
 	CODEC_DUMMY = 0,
 	CODEC_AK5558 = 1,
@@ -353,9 +356,14 @@ static int imx_aif_hw_params(struct snd_pcm_substream *substream,
 		mclk_freq = akcodec_get_mclk_rate(substream, params, slots, slot_width);
 	else
 		mclk_freq = params_rate(params) * slots * slot_width;
-	/* Use the maximum freq from DSD512 (512*44100 = 22579200) */
-	if (format_is_dsd(params))
-		mclk_freq = 22579200;
+
+	if (format_is_dsd(params)) {
+		/* Use the maximum freq from DSD512 (512*44100 = 22579200) */
+		if (!(params_rate(params) % 11025))
+			mclk_freq = IMX_CARD_MCLK_22P5792MHZ;
+		else
+			mclk_freq = IMX_CARD_MCLK_24P576MHZ;
+	}
 
 	ret = snd_soc_dai_set_sysclk(cpu_dai, link_data->cpu_sysclk_id, mclk_freq,
 				     SND_SOC_CLOCK_OUT);
-- 
2.17.1



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