Re: [PATCH 6/7] drm/sun4i: de2: Don't return de2_fmt_info struct

[Chen-Yu Tsai <wens@csie.org>]

On Tue, Feb 25, 2020 at 4:35 PM Maxime Ripard <maxime@cerno.tech> wrote:
>
> Hi,
>
> On Mon, Feb 24, 2020 at 06:39:00PM +0100, Jernej Skrabec wrote:
> > Now that de2_fmt_info contains only DRM <-> HW format mapping, it
> > doesn't make sense to return pointer to structure when searching by DRM
> > format. Rework that to return only HW format instead.
> >
> > This doesn't make any functional change.
> >
> > Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
> > ---
> >  drivers/gpu/drm/sun4i/sun8i_mixer.c    | 15 +++++++++++----
> >  drivers/gpu/drm/sun4i/sun8i_mixer.h    |  7 +------
> >  drivers/gpu/drm/sun4i/sun8i_ui_layer.c | 10 +++++-----
> >  drivers/gpu/drm/sun4i/sun8i_vi_layer.c | 12 ++++++------
> >  4 files changed, 23 insertions(+), 21 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/sun4i/sun8i_mixer.c b/drivers/gpu/drm/sun4i/sun8i_mixer.c
> > index e078ec96de2d..56cc037fd312 100644
> > --- a/drivers/gpu/drm/sun4i/sun8i_mixer.c
> > +++ b/drivers/gpu/drm/sun4i/sun8i_mixer.c
> > @@ -27,6 +27,11 @@
> >  #include "sun8i_vi_layer.h"
> >  #include "sunxi_engine.h"
> >
> > +struct de2_fmt_info {
> > +     u32     drm_fmt;
> > +     u32     de2_fmt;
> > +};
> > +
> >  static const struct de2_fmt_info de2_formats[] = {
> >       {
> >               .drm_fmt = DRM_FORMAT_ARGB8888,
> > @@ -230,15 +235,17 @@ static const struct de2_fmt_info de2_formats[] = {
> >       },
> >  };
> >
> > -const struct de2_fmt_info *sun8i_mixer_format_info(u32 format)
> > +int sun8i_mixer_drm_format_to_hw(u32 format, u32 *hw_format)
> >  {
> >       unsigned int i;
> >
> >       for (i = 0; i < ARRAY_SIZE(de2_formats); ++i)
> > -             if (de2_formats[i].drm_fmt == format)
> > -                     return &de2_formats[i];
> > +             if (de2_formats[i].drm_fmt == format) {
> > +                     *hw_format = de2_formats[i].de2_fmt;
> > +                     return 0;
> > +             }
> >
> > -     return NULL;
> > +     return -EINVAL;
> >  }
>
> I'm not too sure about that one. It breaks the consistency with the
> other functions, and I don't really see a particular benefit to it?

I guess we could just define an "invalid" value, and have the function
return that if can't find a match? I'm guessing 0x0 is valid, so maybe
0xffffffff or 0xdeadbeef ?

That would keep consistency with everything else all the while
removing the level of indirection you wanted to.

ChenYu


> The rest of the series is
> Acked-by: Maxime Ripard <mripard@kernel.org>
>
> Maxime