Re: [PATCH v4 6/8] media: v4l2-ctrls: Add RGB color effects control

[Dillon Min <dillon.minfei@gmail.com>]

Hi Hans

Thanks for quick reply

On Thu, 14 Oct 2021 at 18:44, Hans Verkuil <hverkuil-cisco@xs4all.nl> wrote:
>
> On 14/10/2021 12:25, dillon.minfei@gmail.com wrote:
> > From: Dillon Min <dillon.minfei@gmail.com>
> >
> > Add V4L2_COLORFX_SET_RGB color effects control, V4L2_CID_COLORFX_RGB
> > for RGB color setting.
> >
> > Signed-off-by: Dillon Min <dillon.minfei@gmail.com>
> > ---
> > v4:
> > - replace V4L2_COLORFX_SET_ARGB, V4L2_CID_COLORFX_ARGB to
> >   V4L2_COLORFX_SET_RGB, V4L2_CID_COLORFX_RGB since Alpha paramter not used
> >   in current. thanks Hans.
> >
> >  Documentation/userspace-api/media/v4l/control.rst | 9 +++++++++
> >  drivers/media/v4l2-core/v4l2-ctrls-defs.c         | 2 ++
> >  include/uapi/linux/v4l2-controls.h                | 4 +++-
> >  3 files changed, 14 insertions(+), 1 deletion(-)
> >
> > diff --git a/Documentation/userspace-api/media/v4l/control.rst b/Documentation/userspace-api/media/v4l/control.rst
> > index f8d0b923da20..3eec65174260 100644
> > --- a/Documentation/userspace-api/media/v4l/control.rst
> > +++ b/Documentation/userspace-api/media/v4l/control.rst
> > @@ -242,8 +242,17 @@ Control IDs
> >      * - ``V4L2_COLORFX_SET_CBCR``
> >        - The Cb and Cr chroma components are replaced by fixed coefficients
> >       determined by ``V4L2_CID_COLORFX_CBCR`` control.
> > +    * - ``V4L2_COLORFX_SET_RGB``
> > +      - The RGB components are replaced by the fixed RGB components determined
> > +        by ``V4L2_CID_COLORFX_RGB`` control.
> >
> >
> > +``V4L2_CID_COLORFX_RGB`` ``(integer)``
> > +    Determines the Red, Green, and Blue coefficients for
> > +    ``V4L2_COLORFX_SET_RGB`` color effect.
> > +    Bits [7:0] of the supplied 32 bit value are interpreted as Blue component,
> > +    bits [15:8] as Green component, bits [23:16] as Red component, and
> > +    bits [31:24] must be zero.
> >
> >  ``V4L2_CID_COLORFX_CBCR`` ``(integer)``
> >      Determines the Cb and Cr coefficients for ``V4L2_COLORFX_SET_CBCR``
> > diff --git a/drivers/media/v4l2-core/v4l2-ctrls-defs.c b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> > index 421300e13a41..f4bd90170105 100644
> > --- a/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> > +++ b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> > @@ -785,6 +785,7 @@ const char *v4l2_ctrl_get_name(u32 id)
> >       case V4L2_CID_MIN_BUFFERS_FOR_OUTPUT:   return "Min Number of Output Buffers";
> >       case V4L2_CID_ALPHA_COMPONENT:          return "Alpha Component";
> >       case V4L2_CID_COLORFX_CBCR:             return "Color Effects, CbCr";
> > +     case V4L2_CID_COLORFX_RGB:              return "Color Effects, RGB";
> >
> >       /*
> >        * Codec controls
> > @@ -1392,6 +1393,7 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
> >               *min = *max = *step = *def = 0;
> >               break;
> >       case V4L2_CID_BG_COLOR:
> > +     case V4L2_CID_COLORFX_RGB:
> >               *type = V4L2_CTRL_TYPE_INTEGER;
> >               *step = 1;
> >               *min = 0;
>
> Can you make another small change here? Please change:
>
>         *max = 0xFFFFFF;
>
> to:
>
>         *max = 0xffffff;
>
> to keep in line with the coding standard for hex values.

Sure, do it right now.

>
> Also, can you add a separate patch that adds an entry here for V4L2_CID_COLORFX_CBCR
> that sets *max to 0xffff? I noticed that that was missing. While adding V4L2_CID_COLORFX_RGB
> it's good to fix V4L2_CID_COLORFX_CBCR as well.

Sure, you mean the final code like this? first patch to fix cbcr 0xFFFFFF,
another one to add V4L2_CID_COLORFX_RGB entry.

1395         case V4L2_CID_BG_COLOR:
1396         case V4L2_CID_COLORFX_RGB:
1397                 *type = V4L2_CTRL_TYPE_INTEGER;
1398                 *step = 1;
1399                 *min = 0;
1400                 /* Max is calculated as RGB888 that is 2^24 */
1401                 *max = 0xffffff;
1402                 break;

Best Regards
Dillon

>
> Regards,
>
>         Hans
>
> > diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
> > index 5532b5f68493..9aa3fd368383 100644
> > --- a/include/uapi/linux/v4l2-controls.h
> > +++ b/include/uapi/linux/v4l2-controls.h
> > @@ -128,6 +128,7 @@ enum v4l2_colorfx {
> >       V4L2_COLORFX_SOLARIZATION               = 13,
> >       V4L2_COLORFX_ANTIQUE                    = 14,
> >       V4L2_COLORFX_SET_CBCR                   = 15,
> > +     V4L2_COLORFX_SET_RGB                    = 16,
> >  };
> >  #define V4L2_CID_AUTOBRIGHTNESS                      (V4L2_CID_BASE+32)
> >  #define V4L2_CID_BAND_STOP_FILTER            (V4L2_CID_BASE+33)
> > @@ -145,9 +146,10 @@ enum v4l2_colorfx {
> >
> >  #define V4L2_CID_ALPHA_COMPONENT             (V4L2_CID_BASE+41)
> >  #define V4L2_CID_COLORFX_CBCR                        (V4L2_CID_BASE+42)
> > +#define V4L2_CID_COLORFX_RGB                 (V4L2_CID_BASE+43)
> >
> >  /* last CID + 1 */
> > -#define V4L2_CID_LASTP1                         (V4L2_CID_BASE+43)
> > +#define V4L2_CID_LASTP1                         (V4L2_CID_BASE+44)
> >
> >  /* USER-class private control IDs */
> >
> >
>