[PATCH 3/5] dma: mxs-dma: add device tree probe support

Shawn Guo shawn.guo at linaro.org
Mon Apr 23 13:15:20 EST 2012


On Wed, Apr 18, 2012 at 08:46:35PM +0800, Dong Aisheng wrote:
> From: Dong Aisheng <dong.aisheng at linaro.org>
> 
> Cc: Grant Likely <grant.likely at secretlab.ca>
> Cc: Rob Herring <rob.herring at calxeda.com>
> Cc: Rob Landley <rob at landley.net>
> Cc: Vinod Koul <vinod.koul at intel.com>
> Cc: Dan Williams <dan.j.williams at intel.com>
> Cc: Shawn Guo <shawn.guo at linaro.org>
> Cc: Sascha Hauer <s.hauer at pengutronix.de>
> Cc: Marek Vasut <marek.vasut at gmail.com>
> Cc: Huang Shijie <b32955 at freescale.com>
> Signed-off-by: Dong Aisheng <dong.aisheng at linaro.org>
> ---
>  .../devicetree/bindings/dma/fsl-mxs-dma.txt        |   19 +++++++++++++
>  drivers/dma/mxs-dma.c                              |   29 +++++++++++++++++---
>  2 files changed, 44 insertions(+), 4 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/dma/fsl-mxs-dma.txt b/Documentation/devicetree/bindings/dma/fsl-mxs-dma.txt
> new file mode 100644
> index 0000000..ded0398
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/dma/fsl-mxs-dma.txt
> @@ -0,0 +1,19 @@
> +* Freescale MXS DMA
> +
> +Required properties:
> +- compatible : Should be "fsl,<chip>-dma-apbh" or "fsl,<chip>-dma-apbx"
> +- reg : Should contain registers location and length
> +
> +Supported chips:
> +imx23, imx28.
> +
> +Examples:
> +dma-apbh at 80004000 {
> +	compatible = "fsl,imx28-dma-apbh";
> +	reg = <0x80004000 2000>;
> +};
> +
> +dma-apbx at 80024000 {
> +	compatible = "fsl,imx28-dma-apbx";
> +	reg = <0x80024000 2000>;
> +};
> diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
> index 51a29f9..74c3275 100644
> --- a/drivers/dma/mxs-dma.c
> +++ b/drivers/dma/mxs-dma.c
> @@ -22,8 +22,11 @@
>  #include <linux/platform_device.h>
>  #include <linux/dmaengine.h>
>  #include <linux/delay.h>
> +#include <linux/module.h>
>  #include <linux/fsl/mxs-dma.h>
>  #include <linux/stmp_device.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
>  
>  #include <asm/irq.h>
>  
> @@ -178,6 +181,17 @@ static struct platform_device_id mxs_dma_idt[] = {
>  	}
>  };
>  
> +#ifdef CONFIG_OF
> +static const struct of_device_id mxs_dma_dt_ids[] = {
> +	{ .compatible = "fsl,imx23-dma-apbh", .data = &mxs_dma_idt[0], },
> +	{ .compatible = "fsl,imx23-dma-apbx", .data = &mxs_dma_idt[1], },
> +	{ .compatible = "fsl,imx28-dma-apbh", .data = &mxs_dma_idt[2], },
> +	{ .compatible = "fsl,imx28-dma-apbx", .data = &mxs_dma_idt[3], },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, mxs_dma_dt_ids);
> +#endif
> +
As out goal is to convert mxs over to DT, you can remove the #ifdef
here ...

>  static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
>  {
>  	return container_of(chan, struct mxs_dma_chan, chan);
> @@ -671,10 +685,9 @@ err_out:
>  
>  static int __init mxs_dma_probe(struct platform_device *pdev)
>  {
> -	const struct platform_device_id *id_entry =
> -				platform_get_device_id(pdev);
> -	const struct mxs_dma_type *mtype =
> -			(struct mxs_dma_type *)id_entry->driver_data;
> +	const struct platform_device_id *id_entry;
> +	const struct of_device_id *of_id;
> +	const struct mxs_dma_type *mtype;
>  	struct mxs_dma_engine *mxs_dma;
>  	struct resource *iores;
>  	int ret, i;
> @@ -683,6 +696,13 @@ static int __init mxs_dma_probe(struct platform_device *pdev)
>  	if (!mxs_dma)
>  		return -ENOMEM;
>  
> +	of_id = of_match_device(mxs_dma_dt_ids, &pdev->dev);
> +	if (of_id)
> +		id_entry = of_id->data;
> +	else
> +		id_entry = platform_get_device_id(pdev);
> +
> +	mtype = (struct mxs_dma_type *)id_entry->driver_data;
>  	mxs_dma->type = mtype->type;
>  	mxs_dma->dev_id = mtype->id;
>  
> @@ -770,6 +790,7 @@ err_request_region:
>  static struct platform_driver mxs_dma_driver = {
>  	.driver		= {
>  		.name	= "mxs-dma",
> +		.of_match_table = of_match_ptr(mxs_dma_dt_ids),

... then of_match_ptr is not needed here.

>  	},
>  	.id_table	= mxs_dma_idt,
>  };
> -- 
> 1.7.0.4
> 
> 
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-- 
Regards,
Shawn


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