Re: [PATCH v4 2/2] drivers: dma: altera-msgdma: add OF support

[Stefan Roese <sr@xxxxxxx>]

On 29.04.21 16:18, Olivier Dautricourt wrote:
> This driver had no device tree support.
>
> - add compatible field "altr,msgdma"
> - define msgdma_of_xlate, with no argument
> - register dma controller with of_dma_controller_register
>
> Signed-off-by: Olivier Dautricourt <olivier.dautricourt@xxxxxxxxxx>

Reviewed-by: Stefan Roese <sr@xxxxxxx>

Thanks,
Stefan

> ---
>
> Notes:
>      Changes in v2:
>      	none
>
>      Changes from v2 to v3:
>      	Removed CONFIG_OF #ifdef's and use if (IS_ENABLED(CONFIG_OF))
>      	only once.
>
>      Changes from v3 to v4
>      	Reintroduce #ifdef CONFIG_OF for msgdma_match
>      	as it produces a unused variable warning
>
>   drivers/dma/altera-msgdma.c | 29 +++++++++++++++++++++++++++++
>   1 file changed, 29 insertions(+)
>
> diff --git a/drivers/dma/altera-msgdma.c b/drivers/dma/altera-msgdma.c
> index 9a841ce5f0c5..7e58385facef 100644
> --- a/drivers/dma/altera-msgdma.c
> +++ b/drivers/dma/altera-msgdma.c
> @@ -19,6 +19,7 @@
>   #include <linux/module.h>
>   #include <linux/platform_device.h>
>   #include <linux/slab.h>
> +#include <linux/of_dma.h>
>
>   #include "dmaengine.h"
>
> @@ -784,6 +785,14 @@ static int request_and_map(struct platform_device *pdev, const char *name,
>   	return 0;
>   }
>
> +static struct dma_chan *msgdma_of_xlate(struct of_phandle_args *dma_spec,
> +					struct of_dma *ofdma)
> +{
> +	struct msgdma_device *d = ofdma->of_dma_data;
> +
> +	return dma_get_any_slave_channel(&d->dmadev);
> +}
> +
>   /**
>    * msgdma_probe - Driver probe function
>    * @pdev: Pointer to the platform_device structure
> @@ -888,6 +897,16 @@ static int msgdma_probe(struct platform_device *pdev)
>   	if (ret)
>   		goto fail;
>
> +	if (IS_ENABLED(CONFIG_OF)) {
> +		ret = of_dma_controller_register(pdev->dev.of_node,
> +						 msgdma_of_xlate, mdev);
> +		if (ret) {
> +			dev_err(&pdev->dev,
> +				"failed to register dma controller");
> +			goto fail;
> +		}
> +	}
> +
>   	dev_notice(&pdev->dev, "Altera mSGDMA driver probe success\n");
>
>   	return 0;
> @@ -916,9 +935,19 @@ static int msgdma_remove(struct platform_device *pdev)
>   	return 0;
>   }
>
> +#ifdef CONFIG_OF
> +static const struct of_device_id msgdma_match[] = {
> +	{ .compatible = "altr,msgdma",},
> +	{ }
> +};
> +
> +MODULE_DEVICE_TABLE(of, msgdma_match);
> +#endif
> +
>   static struct platform_driver msgdma_driver = {
>   	.driver = {
>   		.name = "altera-msgdma",
> +		.of_match_table = of_match_ptr(msgdma_match),
>   	},
>   	.probe = msgdma_probe,
>   	.remove = msgdma_remove,
> --
> 2.31.0.rc2


Viele Grüße,
Stefan

--
DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-51 Fax: (+49)-8142-66989-80 Email: sr@xxxxxxx