Re: [PATCH libdrm v2 04/10] util: Add missing big-endian RGB16 frame buffer formats

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
Cc: DRI Development <dri-devel@lists.freedesktop.org>
Subject: Re: [PATCH libdrm v2 04/10] util: Add missing big-endian RGB16 frame buffer formats
Date: Wed, 5 Jul 2023 18:08:15 +0200	[thread overview]
Message-ID: <CAMuHMdXiz8HKe7J8ZH_f=2bFL=gcUPppHungFoyP7QcKbVJ1wQ@mail.gmail.com> (raw)
In-Reply-To: <CAMuHMdVar28SbFvoS0oizNySOpwVYi42mchrvBQqtVm7S3SFww@mail.gmail.com>

Hi Ville,

On Mon, Jul 11, 2022 at 2:34 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> On Mon, Jul 11, 2022 at 2:17 PM Ville Syrjälä
> <ville.syrjala@linux.intel.com> wrote:
> > On Fri, Jul 08, 2022 at 08:21:43PM +0200, Geert Uytterhoeven wrote:
> > > Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
> > > ---
> > > Any better suggestion than appending "be"?
> > >
> > > v2:
> > >   - New.
>
> > > --- a/tests/util/format.c
> > > +++ b/tests/util/format.c
> > > @@ -76,6 +76,9 @@ static const struct util_format_info format_info[] = {
> > >       { DRM_FORMAT_BGRX5551, "BX15", MAKE_RGB_INFO(5, 1, 5, 6, 5, 11, 0, 0) },
> > >       { DRM_FORMAT_RGB565, "RG16", MAKE_RGB_INFO(5, 11, 6, 5, 5, 0, 0, 0) },
> > >       { DRM_FORMAT_BGR565, "BG16", MAKE_RGB_INFO(5, 0, 6, 5, 5, 11, 0, 0) },
> > > +     /* Big-endian RGB16 */
> > > +     { DRM_FORMAT_XRGB1555 | DRM_FORMAT_BIG_ENDIAN, "XR15be", MAKE_RGB_INFO(5, 10, 5, 5, 5, 0, 0, 0) },
> > > +     { DRM_FORMAT_RGB565 | DRM_FORMAT_BIG_ENDIAN, "RG16be", MAKE_RGB_INFO(5, 11, 6, 5, 5, 0, 0, 0) },
> >
> > But I'm not sure why we even store the fourcc as a string in
> > the table anyway. Could just add some kind of string_to_fourcc()
> > thingy instead AFAICS.
>
> I guess that can be done.

Nowadays we have drmGetFormatName(), which returns an allocated string
with the name for a format code.

Using that helper in string_to_fourcc() would mean looping over the
table, and for each entry, calling drmGetFormatName(), comparing the
name, and freeing the name again.
Would that be acceptable?

Thanks!

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds