ASoC: atmel_ssc_dai: make option to choose clock

When SSC works in slave mode, according to the hardware design, the
clock can get from TK pin, also can get from RK pin. So, add one
parameter to choose where the clock from.

Signed-off-by: Bo Shen <voice.shen@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

drivers/misc/atmel-ssc.c

@@ -150,6 +150,12 @@ static int ssc_probe(struct platform_device *pdev)
 		return -ENODEV;
 	ssc->pdata = (struct atmel_ssc_platform_data *)plat_dat;
 
+	if (pdev->dev.of_node) {
+		struct device_node *np = pdev->dev.of_node;
+		ssc->clk_from_rk_pin =
+			of_property_read_bool(np, "atmel,clk-from-rk-pin");
+	}
+
 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	ssc->regs = devm_ioremap_resource(&pdev->dev, regs);
 	if (IS_ERR(ssc->regs))

include/linux/atmel-ssc.h

@@ -18,6 +18,7 @@ struct ssc_device {
 	struct clk		*clk;
 	int			user;
 	int			irq;
+	bool			clk_from_rk_pin;
 };
 
 struct ssc_device * __must_check ssc_request(unsigned int ssc_num);

sound/soc/atmel/atmel_ssc_dai.c

@@ -341,6 +341,7 @@ static int atmel_ssc_hw_params(struct snd_pcm_substream *substream,
 {
 	int id = dai->id;
 	struct atmel_ssc_info *ssc_p = &ssc_info[id];
+	struct ssc_device *ssc = ssc_p->ssc;
 	struct atmel_pcm_dma_params *dma_params;
 	int dir, channels, bits;
 	u32 tfmr, rfmr, tcmr, rcmr;
@@ -466,7 +467,8 @@ static int atmel_ssc_hw_params(struct snd_pcm_substream *substream,
 			| SSC_BF(RCMR_START, start_event)
 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
-			| SSC_BF(RCMR_CKS, SSC_CKS_CLOCK);
+			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
+					   SSC_CKS_PIN : SSC_CKS_CLOCK);
 
 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NONE)
@@ -481,7 +483,8 @@ static int atmel_ssc_hw_params(struct snd_pcm_substream *substream,
 			| SSC_BF(TCMR_START, start_event)
 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
-			| SSC_BF(TCMR_CKS, SSC_CKS_PIN);
+			| SSC_BF(TCMR_CKS, ssc->clk_from_rk_pin ?
+					   SSC_CKS_CLOCK : SSC_CKS_PIN);
 
 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
 			| SSC_BF(TFMR_FSDEN, 0)
@@ -550,7 +553,8 @@ static int atmel_ssc_hw_params(struct snd_pcm_substream *substream,
 			| SSC_BF(RCMR_START, SSC_START_RISING_RF)
 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
-			| SSC_BF(RCMR_CKS, SSC_CKS_PIN);
+			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
+					   SSC_CKS_PIN : SSC_CKS_CLOCK);
 
 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NONE)
@@ -565,7 +569,8 @@ static int atmel_ssc_hw_params(struct snd_pcm_substream *substream,
 			| SSC_BF(TCMR_START, SSC_START_RISING_RF)
 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
-			| SSC_BF(TCMR_CKS, SSC_CKS_PIN);
+			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
+					   SSC_CKS_CLOCK : SSC_CKS_PIN);
 
 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
 			| SSC_BF(TFMR_FSDEN, 0)