Re: [PATCH v2] media: imx: imx7-media-csi: Fix error handling in imx7_csi_async_register()

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Frieder,

Thank you for the patch.

On Wed, Feb 15, 2023 at 06:16:38PM +0100, Frieder Schrempf wrote:
> From: Frieder Schrempf <frieder.schrempf@kontron.de>
> 
> The CSI requires a connected source subdev to operate. If
> fwnode_graph_get_endpoint_by_id() fails and returns NULL, there is no
> point in going on. Print an error message and abort instead.
> 
> Also we don't need to check for an existing asd. Any failure of
> v4l2_async_nf_add_fwnode_remote() should abort the probe.
> 
> Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> ---
> Changes for v2:
> * Improve commit message
> * Use dev_err_probe
> ---
>  drivers/media/platform/nxp/imx7-media-csi.c | 21 ++++++++++-----------
>  1 file changed, 10 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/media/platform/nxp/imx7-media-csi.c b/drivers/media/platform/nxp/imx7-media-csi.c
> index 886374d3a6ff..76ce6ff2c60a 100644
> --- a/drivers/media/platform/nxp/imx7-media-csi.c
> +++ b/drivers/media/platform/nxp/imx7-media-csi.c
> @@ -2191,19 +2191,18 @@ static int imx7_csi_async_register(struct imx7_csi *csi)
>  
>  	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(csi->dev), 0, 0,
>  					     FWNODE_GRAPH_ENDPOINT_NEXT);
> -	if (ep) {
> -		asd = v4l2_async_nf_add_fwnode_remote(&csi->notifier, ep,
> -						      struct v4l2_async_subdev);
> +	if (!ep)
> +		return dev_err_probe(csi->dev, -ENOTCONN,
> +				     "Failed to get remote endpoint\n");
>  
> -		fwnode_handle_put(ep);
> +	asd = v4l2_async_nf_add_fwnode_remote(&csi->notifier, ep,
> +					      struct v4l2_async_subdev);
>  
> -		if (IS_ERR(asd)) {
> -			ret = PTR_ERR(asd);
> -			/* OK if asd already exists */
> -			if (ret != -EEXIST)
> -				return ret;
> -		}
> -	}
> +	fwnode_handle_put(ep);
> +
> +	if (IS_ERR(asd))
> +		return dev_err_probe(csi->dev, PTR_ERR(asd),
> +				     "Failed to add remote subdev to notifier\n");
>  
>  	csi->notifier.ops = &imx7_csi_notify_ops;
>  

-- 
Regards,

Laurent Pinchart