Re: [PATCH v2 10/11] media: rcar-fcp: Handle resets

[Laurent Pinchart]

Hi Paul,

Thank you for the patch.

On Sat, Sep 19, 2026 at 02:07:07AM +0900, Paul Elder wrote:
> On some versions of the FCP, such as the one on the X5H, reset control
> is required to operate the FCP. Add support for handling resets
> optionally, to continue supporting versions that do not require it.
> 
> Signed-off-by: Paul Elder <paul.elder+renesas@xxxxxxxxxxxxxxxx>

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>

> ---
> Changes in v2:
> - handle errors
> ---
>  drivers/media/platform/renesas/rcar-fcp.c | 30 ++++++++++++++++++++++++++++--
>  1 file changed, 28 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/platform/renesas/rcar-fcp.c b/drivers/media/platform/renesas/rcar-fcp.c
> index dfb0ca93e854dd0bb8aedfb757fd786ef6e45542..76d4c250b30815d9eac58f9b54ad923748df79f6 100644
> --- a/drivers/media/platform/renesas/rcar-fcp.c
> +++ b/drivers/media/platform/renesas/rcar-fcp.c
> @@ -16,6 +16,7 @@
>  #include <linux/mutex.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/reset.h>
>  #include <linux/slab.h>
>  
>  #include <media/rcar-fcp.h>
> @@ -29,6 +30,7 @@ struct rcar_fcp_device {
>  	struct list_head list;
>  	struct device *dev;
>  	void __iomem *base;
> +	struct reset_control *rstc;
>  };
>  
>  static LIST_HEAD(fcp_devices);
> @@ -162,20 +164,25 @@ static int rcar_fcp_probe(struct platform_device *pdev)
>  
>  	fcp->dev = &pdev->dev;
>  
> +	platform_set_drvdata(pdev, fcp);
> +
>  	fcp->base = devm_platform_ioremap_resource(pdev, 0);
>  	if (IS_ERR(fcp->base))
>  		return PTR_ERR(fcp->base);
>  
>  	dma_set_max_seg_size(fcp->dev, UINT_MAX);
>  
> +	fcp->rstc = devm_reset_control_get_optional(&pdev->dev, NULL);
> +	if (IS_ERR(fcp->rstc))
> +		return dev_err_probe(&pdev->dev, PTR_ERR(fcp->rstc),
> +				     "failed to get reset control\n");
> +
>  	pm_runtime_enable(&pdev->dev);
>  
>  	mutex_lock(&fcp_lock);
>  	list_add_tail(&fcp->list, &fcp_devices);
>  	mutex_unlock(&fcp_lock);
>  
> -	platform_set_drvdata(pdev, fcp);
> -
>  	return 0;
>  }
>  
> @@ -190,6 +197,24 @@ static void rcar_fcp_remove(struct platform_device *pdev)
>  	pm_runtime_disable(&pdev->dev);
>  }
>  
> +static int fcp_pm_runtime_suspend(struct device *dev)
> +{
> +	struct rcar_fcp_device *fcp = dev_get_drvdata(dev);
> +
> +	return reset_control_assert(fcp->rstc);
> +}
> +
> +static int fcp_pm_runtime_resume(struct device *dev)
> +{
> +	struct rcar_fcp_device *fcp = dev_get_drvdata(dev);
> +
> +	return reset_control_deassert(fcp->rstc);
> +}
> +
> +static const struct dev_pm_ops fcp_pm_ops = {
> +	RUNTIME_PM_OPS(fcp_pm_runtime_suspend, fcp_pm_runtime_resume, NULL)
> +};
> +
>  static const struct of_device_id rcar_fcp_of_match[] = {
>  	{ .compatible = "renesas,fcpf" },
>  	{ .compatible = "renesas,fcpv" },
> @@ -202,6 +227,7 @@ static struct platform_driver rcar_fcp_platform_driver = {
>  	.remove		= rcar_fcp_remove,
>  	.driver		= {
>  		.name	= "rcar-fcp",
> +		.pm = pm_ptr(&fcp_pm_ops),
>  		.of_match_table = rcar_fcp_of_match,
>  		.suppress_bind_attrs = true,
>  	},

-- 
Regards,

Laurent Pinchart