[alsa-devel] [PATCH] ASoC: fsl-asoc-card: Allow to describe master or slave mode

Fabio Estevam festevam at gmail.com
Mon Sep 22 06:40:54 CEST 2014


From: Fabio Estevam <fabio.estevam at freescale.com>

Provide a mechanism to describe whether the system runs in master or slave mode.

In order to keep compatibilty with existing dtb's let slave mode be default one.

Tested on a imx6q-sabresd board in both modes.

Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
---
 Documentation/devicetree/bindings/sound/fsl-asoc-card.txt |  5 +++++
 sound/soc/fsl/fsl-asoc-card.c                             | 15 ++++++++++++---
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt b/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt
index a96774c..1bbc828 100644
--- a/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt
+++ b/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt
@@ -59,6 +59,10 @@ Optional properties:
   - audio-asrc		: The phandle of ASRC. It can be absent if there's no
 			  need to add ASRC support via DPCM.
 
+  - audio-cpu-mode	: The operating mode for the audio cpu interface.
+			  "slave" - audio clock comes from the external codec
+			  "master" -audio clock is generated from the audio cpu
+
 Example:
 sound-cs42888 {
 	compatible = "fsl,imx-audio-cs42888";
@@ -66,6 +70,7 @@ sound-cs42888 {
 	audio-cpu = <&esai>;
 	audio-asrc = <&asrc>;
 	audio-codec = <&cs42888>;
+	audio-cpu-mode = "master";
 	audio-routing =
 		"Line Out Jack", "AOUT1L",
 		"Line Out Jack", "AOUT1R",
diff --git a/sound/soc/fsl/fsl-asoc-card.c b/sound/soc/fsl/fsl-asoc-card.c
index 007c772..bd903cc 100644
--- a/sound/soc/fsl/fsl-asoc-card.c
+++ b/sound/soc/fsl/fsl-asoc-card.c
@@ -393,6 +393,7 @@ static int fsl_asoc_card_probe(struct platform_device *pdev)
 	struct clk *codec_clk;
 	u32 width;
 	int ret;
+	const char *mode;
 
 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
@@ -441,6 +442,17 @@ static int fsl_asoc_card_probe(struct platform_device *pdev)
 	/* Assign a default DAI format, and allow each card to overwrite it */
 	priv->dai_fmt = DAI_FMT_BASE;
 
+	mode = of_get_property(np, "audio-cpu-mode", NULL);
+	if (mode) {
+		if (!strcmp(mode, "master"))
+			priv->dai_fmt |= SND_SOC_DAIFMT_CBS_CFS;
+		else if (!strcmp(mode, "slave"))
+			priv->dai_fmt |= SND_SOC_DAIFMT_CBM_CFM;
+	} else {
+		/* Assign slave mode by default */
+		priv->dai_fmt |= SND_SOC_DAIFMT_CBM_CFM;
+	}
+
 	/* Diversify the card configurations */
 	if (of_device_is_compatible(np, "fsl,imx-audio-cs42888")) {
 		priv->card.set_bias_level = NULL;
@@ -448,16 +460,13 @@ static int fsl_asoc_card_probe(struct platform_device *pdev)
 		priv->cpu_priv.sysclk_freq[RX] = priv->codec_priv.mclk_freq;
 		priv->cpu_priv.sysclk_dir[TX] = SND_SOC_CLOCK_OUT;
 		priv->cpu_priv.sysclk_dir[RX] = SND_SOC_CLOCK_OUT;
-		priv->dai_fmt |= SND_SOC_DAIFMT_CBS_CFS;
 	} else if (of_device_is_compatible(np, "fsl,imx-audio-sgtl5000")) {
 		priv->codec_priv.mclk_id = SGTL5000_SYSCLK;
-		priv->dai_fmt |= SND_SOC_DAIFMT_CBM_CFM;
 	} else if (of_device_is_compatible(np, "fsl,imx-audio-wm8962")) {
 		priv->card.set_bias_level = fsl_asoc_card_set_bias_level;
 		priv->codec_priv.mclk_id = WM8962_SYSCLK_MCLK;
 		priv->codec_priv.fll_id = WM8962_SYSCLK_FLL;
 		priv->codec_priv.pll_id = WM8962_FLL;
-		priv->dai_fmt |= SND_SOC_DAIFMT_CBM_CFM;
 	} else {
 		dev_err(&pdev->dev, "unknown Device Tree compatible\n");
 		return -EINVAL;
-- 
1.9.1



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