[PATCH v6 10/23] drm/i915: Register color correction capabilities

[Shashank Sharma]

>From DRM color management:
============================
DRM color manager supports these color properties:
1. "ctm": Color transformation matrix property, where a
   color transformation matrix of 9 correction values gets
   applied as correction.
2. "palette_before_ctm": for corrections which get applied
   beore color transformation matrix correction.
3. "palette_after_ctm": for corrections which get applied
   after color transformation matrix correction.

These color correction capabilities may differ per platform, supporting
various different no. of correction coefficients. So DRM color manager
support few properties using which a user space can query the platform's
capability, and prepare color correction accordingly.
These query properties are:
1. cm_coeff_after_ctm_property
2. cm_coeff_before_ctm_property
  (CTM is fix to 9 coefficients across industry)

Now, Intel color manager registers:
======================================
1. Gamma correction property as "palette_after_ctm" property
2. Degamma correction capability as "palette_bafore_ctm" property
   capability as "palette_after_ctm" DRM color property hook.
3. CSC as "ctm" property.

So finally, This patch does the following:
1. Add a function which loads the platform's color correction
   capabilities in the cm_crtc_palette_capabilities_property structure.
2. Attaches the cm_crtc_palette_capabilities_property to every CRTC
   getting initiaized.
3. Adds two new parameters "num_samples_after_ctm" and
   "num_samples_before_ctm" in intel_device_info as gamma and
   degamma coefficients vary per platform basis.

Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
Signed-off-by: Kausal Malladi <kausalmalladi at gmail.com>
---
 drivers/gpu/drm/i915/i915_drv.h            |  2 ++
 drivers/gpu/drm/i915/intel_color_manager.c | 31 ++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 8afda45..613bee2 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -789,6 +789,8 @@ struct intel_device_info {
 	u8 num_sprites[I915_MAX_PIPES];
 	u8 gen;
 	u8 ring_mask; /* Rings supported by the HW */
+	u16 num_samples_after_ctm;
+	u16 num_samples_before_ctm;
 	DEV_INFO_FOR_EACH_FLAG(DEFINE_FLAG, SEP_SEMICOLON);
 	/* Register offsets for the various display pipes and transcoders */
 	int pipe_offsets[I915_MAX_TRANSCODERS];
diff --git a/drivers/gpu/drm/i915/intel_color_manager.c b/drivers/gpu/drm/i915/intel_color_manager.c
index b03ee94..334bfff 100644
--- a/drivers/gpu/drm/i915/intel_color_manager.c
+++ b/drivers/gpu/drm/i915/intel_color_manager.c
@@ -30,4 +30,35 @@
 void intel_attach_color_properties_to_crtc(struct drm_device *dev,
 		struct drm_crtc *crtc)
 {
+	struct drm_mode_config *config = &dev->mode_config;
+	struct drm_mode_object *mode_obj = &crtc->base;
+
+	/*
+	* Register:
+	* =========
+	* Gamma correction as palette_after_ctm property
+	* Degamma correction as palette_before_ctm property
+	*
+	* Load:
+	* =====
+	* no. of coefficients supported on this platform for gamma
+	* and degamma with the query properties. A user
+	* space agent should read these query property, and prepare
+	* the color correction values accordingly. Its expected from the
+	* driver to load the right number of coefficients during the init
+	* phase.
+	*/
+	if (config->cm_coeff_after_ctm_property) {
+		drm_object_attach_property(mode_obj,
+			config->cm_coeff_after_ctm_property,
+		INTEL_INFO(dev)->num_samples_after_ctm);
+		DRM_DEBUG_DRIVER("Gamma query property initialized\n");
+	}
+
+	if (config->cm_coeff_before_ctm_property) {
+		drm_object_attach_property(mode_obj,
+			config->cm_coeff_before_ctm_property,
+		INTEL_INFO(dev)->num_samples_before_ctm);
+		DRM_DEBUG_DRIVER("Degamma query property initialized\n");
+	}
 }
-- 
1.9.1