From: Ville Syrjälä Date: Thu, 9 Apr 2026 10:15:38 +0000 (+0300) Subject: drm/i915/hdmi: Make the RGB fallback for "4:2:0 only" modes the last resort X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=654f795ca9d85818991cb9f2851bd5af4c926458;p=thirdparty%2Fkernel%2Flinux.git drm/i915/hdmi: Make the RGB fallback for "4:2:0 only" modes the last resort Currently we take the Hail Mary RGB fallback for "4:2:0 only" modes already during the first pass when respect_downstream_limits==true. It seems better to try everything else first (like ignoring TMDS clock limits) while still preferring 4:2:0, and only if everything else has failed fall back to RGB. Cc: Nicolas Frattaroli Reviewed-by: Ankit Nautiyal Signed-off-by: Ville Syrjälä Link: https://patch.msgid.link/20260409101539.22032-9-ville.syrjala@linux.intel.com Tested-by: Nicolas Frattaroli --- diff --git a/drivers/gpu/drm/i915/display/intel_hdmi.c b/drivers/gpu/drm/i915/display/intel_hdmi.c index 79093d8fc2e61..874076a29da4e 100644 --- a/drivers/gpu/drm/i915/display/intel_hdmi.c +++ b/drivers/gpu/drm/i915/display/intel_hdmi.c @@ -2314,7 +2314,7 @@ static int intel_hdmi_compute_formats(struct intel_encoder *encoder, respect_downstream_limits, INTEL_OUTPUT_FORMAT_YCBCR420); - if (ret) { + if (ret && !respect_downstream_limits) { drm_dbg_kms(display->drm, "YCbCr 4:2:0 mode but YCbCr 4:2:0 output not possible. Falling back to RGB.\n");