Re: [PATCH v2 2/2] drivers: dma: altera-msgdma: add OF support

[Stefan Roese <sr@denx.de>]

On 29.04.21 01:50, 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@orolia.com>
> ---
>   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..2b062d5aa636 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 +785,16 @@ static int request_and_map(struct platform_device *pdev, const char *name,
>   	return 0;
>   }
> 
> +#ifdef CONFIG_OF
> +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);
> +}
> +#endif

To avoid the ugly #ifdef's, could you add this function unconditionally
and ...

> +
>   /**
>    * msgdma_probe - Driver probe function
>    * @pdev: Pointer to the platform_device structure
> @@ -888,6 +899,14 @@ static int msgdma_probe(struct platform_device *pdev)
>   	if (ret)
>   		goto fail;
> 
> +#ifdef 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;
> +	}
> +#endif

... use:

	if (IS_ENABLED(CONFIG_OF)) {
		ret = of_dma_controller_register(pdev->dev.of_node,
		...

here?

>   	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
> +

I think this also can be included unconditionally.

Thanks,
Stefan

>   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
>