Re: [PATCH V3 3/3] ASoC: fsl_asrc: spba clock is needed by asrc device

[Rob Herring <robh@kernel.org>]

On Tue, Nov 24, 2015 at 03:03:30PM +0800, Shengjiu Wang wrote:
> ASRC need to enable the spba clock, when sdma is using share peripheral
> script. In this case, there is two spba master port is used, if don't
> enable the clock, the spba bus will have arbitration issue, which may
> cause read/write wrong data from/to ASRC registers
> 
> Signed-off-by: Shengjiu Wang <shengjiu.wang@freescale.com>
> ---
>  Documentation/devicetree/bindings/sound/fsl,asrc.txt |  5 +++++

For the binding:

Acked-by: Rob Herring <robh@kernel.org>

>  sound/soc/fsl/fsl_asrc.c                             | 10 ++++++++++
>  sound/soc/fsl/fsl_asrc.h                             |  2 ++
>  3 files changed, 17 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/sound/fsl,asrc.txt b/Documentation/devicetree/bindings/sound/fsl,asrc.txt
> index b93362a..3e26a94 100644
> --- a/Documentation/devicetree/bindings/sound/fsl,asrc.txt
> +++ b/Documentation/devicetree/bindings/sound/fsl,asrc.txt
> @@ -25,6 +25,11 @@ Required properties:
>  	"mem"		  Peripheral access clock to access registers.
>  	"ipg"		  Peripheral clock to driver module.
>  	"asrck_<0-f>"	  Clock sources for input and output clock.
> +	"spba"		  The spba clock is required when ASRC is placed as a
> +			  bus slave of the Shared Peripheral Bus and when two
> +			  or more bus masters (CPU, DMA or DSP) try to access
> +			  it. This property is optional depending on the SoC
> +			  design.
>  
>     - big-endian		: If this property is absent, the little endian mode
>  			  will be in use as default. Otherwise, the big endian
> diff --git a/sound/soc/fsl/fsl_asrc.c b/sound/soc/fsl/fsl_asrc.c
> index 9f087d4..800828e 100644
> --- a/sound/soc/fsl/fsl_asrc.c
> +++ b/sound/soc/fsl/fsl_asrc.c
> @@ -859,6 +859,10 @@ static int fsl_asrc_probe(struct platform_device *pdev)
>  		return PTR_ERR(asrc_priv->ipg_clk);
>  	}
>  
> +	asrc_priv->spba_clk = devm_clk_get(&pdev->dev, "spba");
> +	if (IS_ERR(asrc_priv->spba_clk))
> +		dev_warn(&pdev->dev, "failed to get spba clock\n");
> +
>  	for (i = 0; i < ASRC_CLK_MAX_NUM; i++) {
>  		sprintf(tmp, "asrck_%x", i);
>  		asrc_priv->asrck_clk[i] = devm_clk_get(&pdev->dev, tmp);
> @@ -939,6 +943,9 @@ static int fsl_asrc_runtime_resume(struct device *dev)
>  	ret = clk_prepare_enable(asrc_priv->ipg_clk);
>  	if (ret)
>  		goto disable_mem_clk;
> +	ret = clk_prepare_enable(asrc_priv->spba_clk);
> +	if (ret)
> +		goto disable_ipg_clk;
>  	for (i = 0; i < ASRC_CLK_MAX_NUM; i++) {
>  		ret = clk_prepare_enable(asrc_priv->asrck_clk[i]);
>  		if (ret)
> @@ -950,6 +957,8 @@ static int fsl_asrc_runtime_resume(struct device *dev)
>  disable_asrck_clk:
>  	for (i--; i >= 0; i--)
>  		clk_disable_unprepare(asrc_priv->asrck_clk[i]);
> +	clk_disable_unprepare(asrc_priv->spba_clk);
> +disable_ipg_clk:
>  	clk_disable_unprepare(asrc_priv->ipg_clk);
>  disable_mem_clk:
>  	clk_disable_unprepare(asrc_priv->mem_clk);
> @@ -963,6 +972,7 @@ static int fsl_asrc_runtime_suspend(struct device *dev)
>  
>  	for (i = 0; i < ASRC_CLK_MAX_NUM; i++)
>  		clk_disable_unprepare(asrc_priv->asrck_clk[i]);
> +	clk_disable_unprepare(asrc_priv->spba_clk);
>  	clk_disable_unprepare(asrc_priv->ipg_clk);
>  	clk_disable_unprepare(asrc_priv->mem_clk);
>  
> diff --git a/sound/soc/fsl/fsl_asrc.h b/sound/soc/fsl/fsl_asrc.h
> index 4aed63c..68802cd 100644
> --- a/sound/soc/fsl/fsl_asrc.h
> +++ b/sound/soc/fsl/fsl_asrc.h
> @@ -426,6 +426,7 @@ struct fsl_asrc_pair {
>   * @paddr: physical address to the base address of registers
>   * @mem_clk: clock source to access register
>   * @ipg_clk: clock source to drive peripheral
> + * @spba_clk: SPBA clock (optional, depending on SoC design)
>   * @asrck_clk: clock sources to driver ASRC internal logic
>   * @lock: spin lock for resource protection
>   * @pair: pair pointers
> @@ -442,6 +443,7 @@ struct fsl_asrc {
>  	unsigned long paddr;
>  	struct clk *mem_clk;
>  	struct clk *ipg_clk;
> +	struct clk *spba_clk;
>  	struct clk *asrck_clk[ASRC_CLK_MAX_NUM];
>  	spinlock_t lock;
>  
> -- 
> 1.9.1
>