On Mon, Jul 31, 2023 at 09:32:08AM +0200, Jacopo Mondi wrote:
> On Sat, Jul 29, 2023 at 08:13:00PM +0300, Laurent Pinchart wrote:
> > On Mon, Jul 10, 2023 at 05:52:00PM +0200, Jacopo Mondi wrote:
> > > The IMX219 is a RAW sensor. Fix the colorspace configuration by
> > > using V4L2_COLORSPACE_RAW and adjust the quantization and transfer
> > > function values. Drop ycbcr_enc as it doesn't apply to RAW sensors.
> >
> > So this addresses part of my comments for 3/7, nice :-)
> >
> > > Signed-off-by: Jacopo Mondi <jacopo.mondi@xxxxxxxxxxxxxxxx>
> > > ---
> > > drivers/media/i2c/imx219.c | 26 +++++++++-----------------
> > > 1 file changed, 9 insertions(+), 17 deletions(-)
> > >
> > > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
> > > index cd43a897391c..6963e24e1bc2 100644
> > > --- a/drivers/media/i2c/imx219.c
> > > +++ b/drivers/media/i2c/imx219.c
> > > @@ -597,15 +597,12 @@ static void imx219_set_default_format(struct imx219 *imx219)
> > >
> > > fmt = &imx219->fmt;
> > > fmt->code = MEDIA_BUS_FMT_SRGGB10_1X10;
> > > - fmt->colorspace = V4L2_COLORSPACE_SRGB;
> > > - fmt->ycbcr_enc = V4L2_MAP_YCBCR_ENC_DEFAULT(fmt->colorspace);
> > > - fmt->quantization = V4L2_MAP_QUANTIZATION_DEFAULT(true,
> > > - fmt->colorspace,
> > > - fmt->ycbcr_enc);
> > > - fmt->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(fmt->colorspace);
> > > + fmt->colorspace = V4L2_COLORSPACE_RAW;
> > > + fmt->quantization = V4L2_QUANTIZATION_FULL_RANGE;
> > > fmt->width = supported_modes[0].width;
> > > fmt->height = supported_modes[0].height;
> > > fmt->field = V4L2_FIELD_NONE;
> > > + fmt->xfer_func = V4L2_XFER_FUNC_NONE;
> >
> > Any reason to not group xfer_func with colorspace and quantization ?
> >
> > > }
> > >
> > > static int imx219_set_ctrl(struct v4l2_ctrl *ctrl)
> > > @@ -714,12 +711,10 @@ static int imx219_init_cfg(struct v4l2_subdev *sd,
> > > format->code = imx219_get_format_code(imx219,
> > > MEDIA_BUS_FMT_SRGGB10_1X10);
> > > format->field = V4L2_FIELD_NONE;
> > > - format->colorspace = V4L2_COLORSPACE_SRGB;
> > > + format->colorspace = V4L2_COLORSPACE_RAW;
> > > format->ycbcr_enc = V4L2_MAP_YCBCR_ENC_DEFAULT(format->colorspace);
> >
> > You're keeping ycbcr_enc here while you've dropped it in the two other
> > locations. Was that on purpose ?
>
> Umang had the same comment, and I clearly forgot to remove this one
>
> > While the encoding doesn't apply to raw formats, I think it should still
> > be set explicitly, or it will end up having a random value.
>
> Should I use V4L2_YCBCR_ENC_DEFAULT even if for RAW sensors it doesn't
> make much sense ?
For the transfer function we have V4L2_XFER_FUNC_NONE, but for the
encoding we have no similar value. I recall that V4L2_YCBCR_ENC_DEFAULT
is meant for applications only, and that drivers must always return an
appropriate non-default value, but I can't find at the moment where that
is documented. It may have been from a discussion with Hans, and
v4l2-compliance may enforce it, I haven't checked.
We could add a new V4L2_YCBCR_ENC_NONE value, allow
V4L2_YCBCR_ENC_DEFAULT for this use case, or return V4L2_YCBCR_ENC_601
as done by other drivers (this is the value returned by
V4L2_MAP_YCBCR_ENC_DEFAULT() for a RAW colorspace).
> > > - format->quantization = V4L2_MAP_QUANTIZATION_DEFAULT(true,
> > > - format->colorspace,
> > > - format->ycbcr_enc);
> > > - format->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(format->colorspace);
> > > + format->quantization = V4L2_QUANTIZATION_FULL_RANGE;
> > > + format->xfer_func = V4L2_XFER_FUNC_NONE;
> > >
> > > /* Initialize crop rectangle. */
> > > crop = v4l2_subdev_get_pad_crop(sd, state, 0);
> > > @@ -775,12 +770,9 @@ static int imx219_enum_frame_size(struct v4l2_subdev *sd,
> > >
> > > static void imx219_reset_colorspace(struct v4l2_mbus_framefmt *fmt)
> > > {
> > > - fmt->colorspace = V4L2_COLORSPACE_SRGB;
> > > - fmt->ycbcr_enc = V4L2_MAP_YCBCR_ENC_DEFAULT(fmt->colorspace);
> > > - fmt->quantization = V4L2_MAP_QUANTIZATION_DEFAULT(true,
> > > - fmt->colorspace,
> > > - fmt->ycbcr_enc);
> > > - fmt->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(fmt->colorspace);
> > > + fmt->colorspace = V4L2_COLORSPACE_RAW;
> > > + fmt->quantization = V4L2_QUANTIZATION_FULL_RANGE;
> > > + fmt->xfer_func = V4L2_XFER_FUNC_NONE;
> > > }
> > >
> > > static void imx219_update_pad_format(struct imx219 *imx219,
--
Regards,
Laurent Pinchart
