Hi Prabhakar,
Thank you for the patch.
On Fri, Sep 06, 2024 at 06:39:46PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
>
> The RZ/G2L CRU needs to configure the ICnMC.VCSEL bits to specify which
> virtual channel should be processed from the four available VCs. To
> retrieve this information from the connected subdevice, the
> .get_frame_desc() function is called.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> ---
> .../platform/renesas/rzg2l-cru/rzg2l-video.c | 29 +++++++++++++++++++
> 1 file changed, 29 insertions(+)
>
> diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> index bbf4674f888d..6101a070e785 100644
> --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> @@ -433,12 +433,41 @@ void rzg2l_cru_stop_image_processing(struct rzg2l_cru_dev *cru)
> spin_unlock_irqrestore(&cru->qlock, flags);
> }
>
> +static int rzg2l_cru_get_virtual_channel(struct rzg2l_cru_dev *cru)
> +{
> + struct v4l2_mbus_frame_desc fd = { };
> + struct media_pad *pad;
> + int ret;
> +
> + pad = media_pad_remote_pad_unique(&cru->ip.pads[1]);
It would be nice to use RZG2L_CRU_IP_SOURCE here instead of hardcoding
the pad number. That would require moving rzg2l_csi2_pads to the shared
header. You can do that on top.
An now that I've said that, is it really the source pad you need here ?
> + if (IS_ERR(pad))
> + return PTR_ERR(pad);
Can this happen, or would the pipeline fail to validate ? I think you
can set the MUST_CONNECT flag on the sink pad, then you'll have a
guarantee something will be connected.
> +
> + ret = v4l2_subdev_call(cru->ip.remote, pad, get_frame_desc,
> + pad->index, &fd);
> + if (ret < 0 && ret != -ENOIOCTLCMD)
Printing an error message would help debugging.
> + return ret;
> + /* If remote subdev does not implement .get_frame_desc default to VC0. */
> + if (ret == -ENOIOCTLCMD)
> + return 0;
> +
> + if (fd.type != V4L2_MBUS_FRAME_DESC_TYPE_CSI2)
An error message would help here too I think.
> + return -EINVAL;
> +
> + return fd.num_entries ? fd.entry[0].bus.csi2.vc : 0;
I think you should return an error if fd.num_entries is 0, that
shouldn't happen.
> +}
> +
> int rzg2l_cru_start_image_processing(struct rzg2l_cru_dev *cru)
> {
> struct v4l2_mbus_framefmt *fmt = rzg2l_cru_ip_get_src_fmt(cru);
> unsigned long flags;
> int ret;
>
> + ret = rzg2l_cru_get_virtual_channel(cru);
> + if (ret < 0)
> + return ret;
> + cru->csi.channel = ret;
How about passing the value to the function that needs it, instead of
storing it in cru->csi.channel ? You can do that on top and drop the
csi.channel field.
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> +
> spin_lock_irqsave(&cru->qlock, flags);
>
> /* Select a video input */
--
Regards,
Laurent Pinchart
