Re: [PATCH 6/9] media: sun6i-csi: capture: Implement MC I/O with extended enum_fmt

From: Laurent Pinchart
Date: Sat Mar 25 2023 - 17:29:55 EST


Hi Paul,

Thank you for the patch.

On Fri, Mar 24, 2023 at 04:12:25PM +0100, Paul Kocialkowski wrote:
> This driver needs the media-controller API to operate and should not be
> considered as a video-device-centric implementation.
>
> Properly report the IO_MC device cap and extend the enum_fmt
> implementation to support enumeration with an explicit mbus_code.
>
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@xxxxxxxxxxx>
> ---
> .../sunxi/sun6i-csi/sun6i_csi_capture.c | 36 ++++++++++++++++---
> 1 file changed, 32 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c
> index 6ce7f1d3ed57..9627030ff060 100644
> --- a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c
> +++ b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c
> @@ -777,13 +777,40 @@ static int sun6i_csi_capture_enum_fmt(struct file *file, void *private,
> struct v4l2_fmtdesc *fmtdesc)
> {
> u32 index = fmtdesc->index;
> + u32 mbus_code = fmtdesc->mbus_code;
> + unsigned int index_valid = 0;
> + unsigned int i;
> +
> + if (!mbus_code) {
> + if (index >= ARRAY_SIZE(sun6i_csi_capture_formats))
> + return -EINVAL;
> +
> + fmtdesc->pixelformat =
> + sun6i_csi_capture_formats[index].pixelformat;
> +
> + return 0;
> + }
> +
> + /* Check capture pixel format matching with mbus code. */
>
> - if (index >= ARRAY_SIZE(sun6i_csi_capture_formats))
> + if (!sun6i_csi_bridge_format_find(mbus_code))
> return -EINVAL;
>
> - fmtdesc->pixelformat = sun6i_csi_capture_formats[index].pixelformat;
> + for (i = 0; i < ARRAY_SIZE(sun6i_csi_capture_formats); i++) {
> + u32 pixelformat = sun6i_csi_capture_formats[i].pixelformat;
>
> - return 0;
> + if (!sun6i_csi_capture_format_check(pixelformat, mbus_code))
> + continue;

I would probably have added compatible media bus codes to the
sun6i_csi_capture_format structure. This should work though, even if it
is more CPU-intensive. I'm OK with either option.

> +
> + if (index == index_valid) {

You can replace this with

if (index == 0) {

and

index_valid++;

with

index--;

below, and drop the index_valid variable.

> + fmtdesc->pixelformat = pixelformat;
> + return 0;
> + }
> +
> + index_valid++;
> + }
> +
> + return -EINVAL;
> }
>
> static int sun6i_csi_capture_g_fmt(struct file *file, void *private,
> @@ -1039,7 +1066,8 @@ int sun6i_csi_capture_setup(struct sun6i_csi_device *csi_dev)
>
> strscpy(video_dev->name, SUN6I_CSI_CAPTURE_NAME,
> sizeof(video_dev->name));
> - video_dev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
> + video_dev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING |
> + V4L2_CAP_IO_MC;
> video_dev->vfl_dir = VFL_DIR_RX;
> video_dev->release = video_device_release_empty;

--
Regards,

Laurent Pinchart