Re: [PATCH v1 3/3] media: sun6i-csi: capture: Support MC-centric format enumeration

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

On Thu, May 07, 2026 at 01:58:08PM +0200, Paul Kocialkowski wrote:
> Le Tue 17 Feb 26, 10:10, Arash Golgol a écrit :
> > Extend vidioc_enum_fmt to support MC-centric enumeration by filtering
> > pixel formats based on the provided mbus code. Advertise MC I/O support
> > on the video device to reflect its intended usage within a media graph.
> > 
> > Signed-off-by: Arash Golgol <arash.golgol@gmail.com>
> > ---
> >  .../sunxi/sun6i-csi/sun6i_csi_capture.c       | 38 +++++++++++++++++--
> >  1 file changed, 35 insertions(+), 3 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 dd06d4c116e0..f54d7a6397be 100644
> > --- a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c
> > +++ b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c
> > @@ -327,6 +327,21 @@ static bool sun6i_csi_capture_format_match(u32 pixelformat, u32 mbus_code)
> >  	return false;
> >  }
> >  
> > +static const u32 *sun6i_csi_capture_pixelformat_find(u32 mbus_code)
> 
> I am not a big fan of returning a pointer here. We can safely assume
> that a valid pixel format will be non-zero (it's a fourcc), so I would
> just return the pixelformat directly and 0 for invalid cases.

I agree. The rest of the patch looks fine. With this addressed,

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

> > +{
> > +	unsigned int i;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(sun6i_csi_capture_format_matches); i++) {
> > +		const struct sun6i_csi_capture_format_match *match =
> > +			&sun6i_csi_capture_format_matches[i];
> > +
> > +		if (match->mbus_code == mbus_code)
> > +			return &match->pixelformat;
> > +	}
> > +
> > +	return NULL;
> > +}
> > +
> >  /* Capture */
> >  
> >  static void
> > @@ -729,11 +744,27 @@ static int sun6i_csi_capture_enum_fmt(struct file *file, void *priv,
> >  				      struct v4l2_fmtdesc *fmtdesc)
> >  {
> >  	u32 index = fmtdesc->index;
> > +	u32 mbus_code = fmtdesc->mbus_code;
> > +	const u32 *pixelformat;
> > +
> > +	/* MC-centric or Video-node-centric */
> > +	if (mbus_code) {
> > +		/* There is only one pixelformat for a mbus_code. */
> > +		if (index)
> > +			return -EINVAL;
> > +
> > +		pixelformat = sun6i_csi_capture_pixelformat_find(mbus_code);
> > +	} else {
> > +		if (index >= ARRAY_SIZE(sun6i_csi_capture_formats))
> > +			return -EINVAL;
> > +
> > +		pixelformat = &sun6i_csi_capture_formats[index].pixelformat;
> > +	}
> >  
> > -	if (index >= ARRAY_SIZE(sun6i_csi_capture_formats))
> > +	if (!pixelformat)
> >  		return -EINVAL;
> >  
> > -	fmtdesc->pixelformat = sun6i_csi_capture_formats[index].pixelformat;
> > +	fmtdesc->pixelformat = *pixelformat;
> >  
> >  	return 0;
> >  }
> > @@ -1065,7 +1096,8 @@ 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;
> >  	video_dev->fops = &sun6i_csi_capture_fops;

-- 
Regards,

Laurent Pinchart