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

From: Laurent Pinchart
Date: Wed Feb 15 2023 - 12:26:51 EST


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@xxxxxxxxxx>
>
> 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@xxxxxxxxxxxxxxxx>
> Signed-off-by: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx>

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

> ---
> 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