Re: [alsa-devel] [PATCH 4/6] ASoC: mxs: add device tree support for mxs-saif

On Thu, May 10, 2012 at 04:42:11PM +0800, Shawn Guo wrote:

Add device tree probe for mxs-saif driver.

Signed-off-by: Shawn Guo shawn.guo@linaro.org

.../devicetree/bindings/sound/mxs-saif.txt | 36 ++++++++++ sound/soc/mxs/mxs-saif.c | 74 +++++++++++++++----- 2 files changed, 93 insertions(+), 17 deletions(-) create mode 100644 Documentation/devicetree/bindings/sound/mxs-saif.txt

diff --git a/Documentation/devicetree/bindings/sound/mxs-saif.txt b/Documentation/devicetree/bindings/sound/mxs-saif.txt new file mode 100644 index 0000000..c37ba61 --- /dev/null +++ b/Documentation/devicetree/bindings/sound/mxs-saif.txt @@ -0,0 +1,36 @@ +* Freescale MXS Serial Audio Interface (SAIF)

+Required properties: +- compatible: Should be "fsl,<chip>-saif" +- reg: Should contain registers location and length +- interrupts: Should contain ERROR and DMA interrupts +- fsl,saif-dma-channel: APBX DMA channel for the SAIF

+Optional properties: +- fsl,saif-master: phandle to the master SAIF. It's only required for

• the slave SAIF.

+Note: Each SAIF controller should have an alias correctly numbered +in "aliases" node.

+Example:

+aliases {

• saif0 = &saif0;
• saif1 = &saif1;

+};

+saif0: saif@80042000 {

• compatible = "fsl,imx28-saif";
• reg = <0x80042000 2000>;
• interrupts = <59 80>;
• fsl,saif-dma-channel = <4>;

+};

+saif1: saif@80046000 {

• compatible = "fsl,imx28-saif";
• reg = <0x80046000 2000>;
• interrupts = <58 81>;
• fsl,saif-dma-channel = <5>;
• fsl,saif-master = <&saif0>;

+}; diff --git a/sound/soc/mxs/mxs-saif.c b/sound/soc/mxs/mxs-saif.c index fa80ee6..ca1e77c 100644 --- a/sound/soc/mxs/mxs-saif.c +++ b/sound/soc/mxs/mxs-saif.c @@ -18,6 +18,8 @@

#include <linux/module.h> #include <linux/init.h> +#include <linux/of.h> +#include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/dma-mapping.h> @@ -623,35 +625,58 @@ static irqreturn_t mxs_saif_irq(int irq, void *dev_id)

static int __devinit mxs_saif_probe(struct platform_device *pdev) {

• struct device_node *np = pdev->dev.of_node; struct resource *iores, *dmares; struct mxs_saif *saif; struct mxs_saif_platform_data *pdata; struct pinctrl *pinctrl; int ret = 0;

• if (pdev->id >= ARRAY_SIZE(mxs_saif))

• if (!np && pdev->id >= ARRAY_SIZE(mxs_saif)) return -EINVAL;

  saif = devm_kzalloc(&pdev->dev, sizeof(*saif), GFP_KERNEL); if (!saif) return -ENOMEM;

• mxs_saif[pdev->id] = saif;
• saif->id = pdev->id;
• pdata = pdev->dev.platform_data;
• if (pdata && !pdata->master_mode) {

• saif->master_id = pdata->master_id;
  

• if (saif->master_id < 0 ||
  

• 	saif->master_id >= ARRAY_SIZE(mxs_saif) ||
  

• 	saif->master_id == saif->id) {
  

• 	dev_err(&pdev->dev, "get wrong master id\n");
  

• 	return -EINVAL;
  

• if (np) {

• struct device_node *master;
  

• saif->id = of_alias_get_id(np, "saif");
  

• if (saif->id < 0)
  

• 	return saif->id;
  

• /*
  

•  * If there is no "fsl,saif-master" phandle, it's a saif
  

•  * master.  Otherwise, it's a slave and its phandle points
  

•  * to the master.
  

•  */
  

• master = of_parse_phandle(np, "fsl,saif-master", 0);
  

• if (!master) {
  

• 	saif->master_id = saif->id;
  

• } else {
  

• 	saif->master_id = of_alias_get_id(master, "saif");
  

• 	if (saif->master_id < 0)
  

• 		return saif->master_id;
  

  } } else {

• saif->master_id = saif->id;
  

• saif->id = pdev->id;
  

• pdata = pdev->dev.platform_data;
  

• if (pdata && !pdata->master_mode) {
  

• 	saif->master_id = pdata->master_id;
  

• 	if (saif->master_id < 0 ||
  

• 		saif->master_id >= ARRAY_SIZE(mxs_saif) ||
  

• 		saif->master_id == saif->id) {
  

• 		dev_err(&pdev->dev, "get wrong master id\n");
  

• 		return -EINVAL;
  

Maybe we could put the master_id validation code out to below since for dt case it also needs it.

Otherwise the code looks ok to me.

Regards Dong Aisheng