ASoC: fsl_spdif: Add support for imx6sx platform

The one difference on imx6sx platform is that the root clock
is shared with ASRC module, so we add a new flags
"shared_root_clock" which means the root clock is not independent,
then we will not do the clk_set_rate and clk_round_rate to avoid
impact ASRC module usage.

As add a new flags, we include the soc specific data struct.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
Link: https://lore.kernel.org/r/7a343edd5f8487abad248a0b862f45fd95067751.1592376770.git.shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/fsl/fsl_spdif.c

@@ -42,6 +42,18 @@ static u8 srpc_dpll_locked[] = { 0x0, 0x1, 0x2, 0x3, 0x4, 0xa, 0xb };
 
 #define DEFAULT_RXCLK_SRC	1
 
+/**
+ * struct fsl_spdif_soc_data: soc specific data
+ *
+ * @imx: for imx platform
+ * @shared_root_clock: flag of sharing a clock source with others;
+ *                     so the driver shouldn't set root clock rate
+ */
+struct fsl_spdif_soc_data {
+	bool imx;
+	bool shared_root_clock;
+};
+
 /*
  * SPDIF control structure
  * Defines channel status, subcode and Q sub
@@ -89,6 +101,7 @@ struct spdif_mixer_control {
  * @dma_params_rx: DMA parameters for receive channel
  */
 struct fsl_spdif_priv {
+	const struct fsl_spdif_soc_data *soc;
 	struct spdif_mixer_control fsl_spdif_control;
 	struct snd_soc_dai_driver cpu_dai_drv;
 	struct platform_device *pdev;
@@ -110,6 +123,27 @@ struct fsl_spdif_priv {
 	u32 regcache_srpc;
 };
 
+static struct fsl_spdif_soc_data fsl_spdif_vf610 = {
+	.imx = false,
+	.shared_root_clock = false,
+};
+
+static struct fsl_spdif_soc_data fsl_spdif_imx35 = {
+	.imx = true,
+	.shared_root_clock = false,
+};
+
+static struct fsl_spdif_soc_data fsl_spdif_imx6sx = {
+	.imx = true,
+	.shared_root_clock = true,
+};
+
+/* Check if clk is a root clock that does not share clock source with others */
+static inline bool fsl_spdif_can_set_clk_rate(struct fsl_spdif_priv *spdif, int clk)
+{
+	return (clk == STC_TXCLK_SPDIF_ROOT) && !spdif->soc->shared_root_clock;
+}
+
 /* DPLL locked and lock loss interrupt handler */
 static void spdif_irq_dpll_lock(struct fsl_spdif_priv *spdif_priv)
 {
@@ -420,8 +454,7 @@ static int spdif_set_sample_rate(struct snd_pcm_substream *substream,
 
 	sysclk_df = spdif_priv->sysclk_df[rate];
 
-	/* Don't mess up the clocks from other modules */
-	if (clk != STC_TXCLK_SPDIF_ROOT)
+	if (!fsl_spdif_can_set_clk_rate(spdif_priv, clk))
 		goto clk_set_bypass;
 
 	/* The S/PDIF block needs a clock of 64 * fs * txclk_df */
@@ -1186,7 +1219,7 @@ static int fsl_spdif_probe_txclk(struct fsl_spdif_priv *spdif_priv,
 			continue;
 
 		ret = fsl_spdif_txclk_caldiv(spdif_priv, clk, savesub, index,
-					     i == STC_TXCLK_SPDIF_ROOT);
+					     fsl_spdif_can_set_clk_rate(spdif_priv, i));
 		if (savesub == ret)
 			continue;
 
@@ -1230,6 +1263,12 @@ static int fsl_spdif_probe(struct platform_device *pdev)
 
 	spdif_priv->pdev = pdev;
 
+	spdif_priv->soc = of_device_get_match_data(&pdev->dev);
+	if (!spdif_priv->soc) {
+		dev_err(&pdev->dev, "failed to get soc data\n");
+		return -ENODEV;
+	}
+
 	/* Initialize this copy of the CPU DAI driver structure */
 	memcpy(&spdif_priv->cpu_dai_drv, &fsl_spdif_dai, sizeof(fsl_spdif_dai));
 	spdif_priv->cpu_dai_drv.name = dev_name(&pdev->dev);
@@ -1359,8 +1398,9 @@ static const struct dev_pm_ops fsl_spdif_pm = {
 };
 
 static const struct of_device_id fsl_spdif_dt_ids[] = {
-	{ .compatible = "fsl,imx35-spdif", },
-	{ .compatible = "fsl,vf610-spdif", },
+	{ .compatible = "fsl,imx35-spdif", .data = &fsl_spdif_imx35, },
+	{ .compatible = "fsl,vf610-spdif", .data = &fsl_spdif_vf610, },
+	{ .compatible = "fsl,imx6sx-spdif", .data = &fsl_spdif_imx6sx, },
 	{}
 };
 MODULE_DEVICE_TABLE(of, fsl_spdif_dt_ids);