On Wed, Aug 26, 2020 at 01:21:15PM +0800, Kai-Heng Feng wrote:
> LSPCON only supports 8 bpc for RGB/YCbCr444.
>
> Set the correct bpp otherwise it renders blank screen.
Hmm. Does
git://github.com/vsyrjala/linux.git dp_downstream_ports_5
work?
Actually better make that dp_downstream_ports_5^^^^^^^^^^^ aka.
54d846ce62a2 ("drm/i915: Do YCbCr 444->420 conversion via DP protocol
converters") to avoid the experiments and hacks I have sitting on top.
>
> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/2195
> Signed-off-by: Kai-Heng Feng <kai.heng.f...@canonical.com>
> ---
> drivers/gpu/drm/i915/display/intel_lspcon.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_lspcon.c
> b/drivers/gpu/drm/i915/display/intel_lspcon.c
> index b781bf469644..c7a44fcaade8 100644
> --- a/drivers/gpu/drm/i915/display/intel_lspcon.c
> +++ b/drivers/gpu/drm/i915/display/intel_lspcon.c
> @@ -196,7 +196,8 @@ void lspcon_ycbcr420_config(struct drm_connector
> *connector,
> crtc_state->port_clock /= 2;
> crtc_state->output_format = INTEL_OUTPUT_FORMAT_YCBCR444;
> crtc_state->lspcon_downsampling = true;
> - }
> + } else
> + crtc_state->pipe_bpp = 24;
> }
>
> static bool lspcon_probe(struct intel_lspcon *lspcon)
> --
> 2.17.1
--
Ville Syrjälä
Intel
