[RESEND PATCH v11 11/18] drm: exynos: dsi: Add atomic_get_input_bus_fmts

[Jagan Teki]

On Wed, Jan 25, 2023 at 2:49 AM Marek Vasut <marex at denx.de> wrote:
>
> On 1/24/23 22:16, Jagan Teki wrote:
> > On Wed, Jan 25, 2023 at 2:15 AM Marek Vasut <marex at denx.de> wrote:
> >>
> >> On 1/23/23 16:12, Jagan Teki wrote:
> >>
> >> [...]
> >>
> >>> +static bool exynos_dsi_pixel_output_fmt_supported(u32 fmt)
> >>> +{
> >>> +     int i;
> >>
> >> if (fmt == MEDIA_BUS_FMT_FIXED)
> >>    return false;
> >>
> >>> +     for (i = 0; i < ARRAY_SIZE(exynos_dsi_pixel_output_fmts); i++) {
> >>> +             if (exynos_dsi_pixel_output_fmts[i] == fmt)
> >>> +                     return true;
> >>> +     }
> >>> +
> >>> +     return false;
> >>> +}
> >>> +
> >>> +static u32 *
> >>> +exynos_dsi_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
> >>> +                                  struct drm_bridge_state *bridge_state,
> >>> +                                  struct drm_crtc_state *crtc_state,
> >>> +                                  struct drm_connector_state *conn_state,
> >>> +                                  u32 output_fmt,
> >>> +                                  unsigned int *num_input_fmts)
> >>> +{
> >>> +     u32 *input_fmts;
> >>> +
> >>> +     if (!exynos_dsi_pixel_output_fmt_supported(output_fmt))
> >>> +             /*
> >>> +              * Some bridge/display drivers are still not able to pass the
> >>> +              * correct format, so handle those pipelines by falling back
> >>> +              * to the default format till the supported formats finalized.
> >>> +              */
> >>> +             output_fmt = MEDIA_BUS_FMT_RGB888_1X24;
> >>
> >> You can move this ^ past the kmalloc() call, so in unlikely case the
> >> kmalloc() fails, it would fail first.
> >
> > I didn't get this point, what do we need to do if
> > exynos_dsi_pixel_output_fmt_supported returns false?
>
> {
>         u32 *input_fmts;
>
>         input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
>         if (!input_fmts)
>                 return NULL;
>
>         if (!exynos_dsi_pixel_output_fmt_supported(output_fmt))
>                 /* ... the comment ... */
>                 output_fmt = MEDIA_BUS_FMT_RGB888_1X24;
>
>         input_fmts[0] = output_fmt;
>         *num_input_fmts = 1;
>
>         return input_fmts;
> }

Got it, thanks!