Hi,
On Thu, Sep 17, 2015 at 02:09:23PM +0800, Shengjiu Wang wrote:
esai need to enable the spba clock, when sdma is using share peripheral script. If don't enable it, may cause the read/write wrong data from/to register.
It would be nicer to elaborate the SPBA as well, especially the reason why it "may cause the read/write wrong data from/to register".
Signed-off-by: Shengjiu Wang shengjiu.wang@freescale.com
diff --git a/Documentation/devicetree/bindings/sound/fsl,esai.txt b/Documentation/devicetree/bindings/sound/fsl,esai.txt index d3b6b5f..d677203 100644 --- a/Documentation/devicetree/bindings/sound/fsl,esai.txt +++ b/Documentation/devicetree/bindings/sound/fsl,esai.txt @@ -27,6 +27,8 @@ Required properties: derive HCK, SCK and FS. "fsys" The system clock derived from ahb clock used to derive HCK, SCK and FS.
- "dma" The spba clock is needed when sdma share peripheral
script is used.
It would be better to treat it as an optional property as ESAI itself doesn't require it to be enabled while a specific SDMA script does so as to access the registers successfully via the arbiter. There is one of existing SoCs that doesn't have SDMA and SPBA at all so they don't need it.
@@ -469,6 +470,9 @@ static int fsl_esai_startup(struct snd_pcm_substream *substream, ret = clk_prepare_enable(esai_priv->coreclk); if (ret) return ret;
- ret = clk_prepare_enable(esai_priv->dmaclk);
- if (ret)
return ret;
Needs a goto for a failed case in order to disable the coreclk.
@@ -772,6 +778,13 @@ static int fsl_esai_probe(struct platform_device *pdev) dev_warn(&pdev->dev, "failed to get fsys clock: %ld\n", PTR_ERR(esai_priv->fsysclk));
- esai_priv->dmaclk = devm_clk_get(&pdev->dev, "dma");
- if (IS_ERR(esai_priv->dmaclk)) {
dev_err(&pdev->dev, "Cannot get dma clock: %ld\n",PTR_ERR(esai_priv->dmaclk));return PTR_ERR(esai_priv->dmaclk);- }
This will break the old DTB -- would be solved by making the clock optional though. And it would be better to follow the pattern of previous error message.
Nicolin