[Intel-gfx] [PATCH 09/11] drm/i915: Reject YCbCr output with degamma+gamma on pre-icl

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Since the pipe CSC sits between the degamma and gamma LUTs there
is no way to make us it for RGB->YCbCr conversion when both LUTs
are also active. Simply reject such combos.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_color.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_color.c b/drivers/gpu/drm/i915/display/intel_color.c
index 435394cad359..926784f266f2 100644
--- a/drivers/gpu/drm/i915/display/intel_color.c
+++ b/drivers/gpu/drm/i915/display/intel_color.c
@@ -1556,7 +1556,14 @@ static int ivb_color_check(struct intel_crtc_state *crtc_state)
 	if (crtc_state->output_format != INTEL_OUTPUT_FORMAT_RGB &&
 	    crtc_state->hw.ctm) {
 		drm_dbg_kms(&i915->drm,
-			    "YCBCR and CTM together are not possible\n");
+			    "YCbCr and CTM together are not possible\n");
+		return -EINVAL;
+	}
+
+	if (crtc_state->output_format != INTEL_OUTPUT_FORMAT_RGB &&
+	    crtc_state->hw.degamma_lut && crtc_state->hw.gamma_lut) {
+		drm_dbg_kms(&i915->drm,
+			    "YCbCr and degamma+gamma together are not possible\n");
 		return -EINVAL;
 	}
 
@@ -1622,7 +1629,14 @@ static int glk_color_check(struct intel_crtc_state *crtc_state)
 	if (crtc_state->output_format != INTEL_OUTPUT_FORMAT_RGB &&
 	    crtc_state->hw.ctm) {
 		drm_dbg_kms(&i915->drm,
-			    "YCBCR and CTM together are not possible\n");
+			    "YCbCr and CTM together are not possible\n");
+		return -EINVAL;
+	}
+
+	if (crtc_state->output_format != INTEL_OUTPUT_FORMAT_RGB &&
+	    crtc_state->hw.degamma_lut && crtc_state->hw.gamma_lut) {
+		drm_dbg_kms(&i915->drm,
+			    "YCbCr and degamma+gamma together are not possible\n");
 		return -EINVAL;
 	}
 
-- 
2.37.4