[PATCH v2 1/2] ASoC: bindings: fsl_spdif: Add new compatible string for imx6sx

[PATCH v2 1/2] ASoC: bindings: fsl_spdif: Add new compatible string for imx6sx

[Shengjiu Wang]

Add new compatible string "fsl,imx6sx-spdif" in the binding document.
And add compatible string "fsl,vf610-spdif" which was missed before.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
---
 Documentation/devicetree/bindings/sound/fsl,spdif.txt | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/sound/fsl,spdif.txt b/Documentation/devicetree/bindings/sound/fsl,spdif.txt
index 8b324f82a782..e1365b0ee1e9 100644
--- a/Documentation/devicetree/bindings/sound/fsl,spdif.txt
+++ b/Documentation/devicetree/bindings/sound/fsl,spdif.txt
@@ -6,7 +6,11 @@ a fibre cable.
 
 Required properties:
 
-  - compatible		: Compatible list, must contain "fsl,imx35-spdif".
+  - compatible		: Compatible list, should contain one of the following
+			  compatibles:
+			  "fsl,imx35-spdif",
+			  "fsl,vf610-spdif",
+			  "fsl,imx6sx-spdif",
 
   - reg			: Offset and length of the register set for the device.
 
-- 
2.21.0

[PATCH v2 2/2] ASoC: fsl_spdif: Add support for imx6sx platform

[Shengjiu Wang]

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 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>
---
changes in v2
- use shared_root_clk instead ind_root_clk.
- add fsl_spdif_can_set_clk_rate function.

 sound/soc/fsl/fsl_spdif.c | 50 +++++++++++++++++++++++++++++++++++----
 1 file changed, 46 insertions(+), 4 deletions(-)

diff --git a/sound/soc/fsl/fsl_spdif.c b/sound/soc/fsl/fsl_spdif.c
index 1b2e516f9162..8dc1959d0463 100644
--- a/sound/soc/fsl/fsl_spdif.c
+++ b/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 +123,28 @@ 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)
 {
@@ -421,7 +456,7 @@ 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 +1221,7 @@ 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 +1265,12 @@ 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 +1400,9 @@ 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);
-- 
2.21.0

Re: [PATCH v2 2/2] ASoC: fsl_spdif: Add support for imx6sx platform

[Nicolin Chen]

On Wed, Jun 17, 2020 at 12:30:17PM +0800, Shengjiu Wang wrote:
> 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 independent,

"shared" means "not independent", against "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>

Can add this once fixing the remaining comments:

Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>

> +static inline bool fsl_spdif_can_set_clk_rate(struct fsl_spdif_priv *spdif,
> +					      int clk)

Can actually merge into single line as kernel has 100-character
limit now, though 80-char is still preferable for a good coding
style. But I think this one wouldn't be too bad at all.

> @@ -421,7 +456,7 @@ 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 */

We can drop this comments now as it's out-of-date and the name of
the new helper function is straightforward enough.

> -	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 */

Re: [PATCH v2 2/2] ASoC: fsl_spdif: Add support for imx6sx platform

[Shengjiu Wang]

On Wed, Jun 17, 2020 at 2:27 PM Nicolin Chen <nicoleotsuka@gmail.com> wrote:
>
> On Wed, Jun 17, 2020 at 12:30:17PM +0800, Shengjiu Wang wrote:
> > 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 independent,
>
> "shared" means "not independent", against "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>
>
> Can add this once fixing the remaining comments:
>
> Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
>
> > +static inline bool fsl_spdif_can_set_clk_rate(struct fsl_spdif_priv *spdif,
> > +                                           int clk)
>
> Can actually merge into single line as kernel has 100-character
> limit now, though 80-char is still preferable for a good coding
> style. But I think this one wouldn't be too bad at all.
>
> > @@ -421,7 +456,7 @@ 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 */
>
> We can drop this comments now as it's out-of-date and the name of
> the new helper function is straightforward enough.
>

ok, will send v3.

best regards
wang shengjiu