[PATCH V8 38/43] drm/colorop: Define LUT_1D interpolation

[Alex Hung <alex.hung@amd.com>]

From: Harry Wentland <harry.wentland@amd.com>

We want to make sure userspace is aware of the 1D LUT
interpolation. While linear interpolation is common it
might not be supported on all HW. Give driver implementers
a way to specify their interpolation.

Reviewed-by: Simon Ser <contact@emersion.fr>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
---
v7:
 - Fix a checkpatch long-line warning
 - Modify state->size to colorop->lut_size

 .../amd/display/amdgpu_dm/amdgpu_dm_colorop.c |  6 ++--
 drivers/gpu/drm/drm_atomic.c                  |  2 ++
 drivers/gpu/drm/drm_colorop.c                 | 36 ++++++++++++++++++-
 include/drm/drm_colorop.h                     | 19 +++++++++-
 include/uapi/drm/drm_mode.h                   | 13 +++++++
 5 files changed, 72 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.c
index d0777691862b..92c9f3fb0254 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_colorop.c
@@ -131,7 +131,8 @@ int amdgpu_dm_initialize_default_pipeline(struct drm_plane *plane, struct drm_pr
 		goto cleanup;
 	}
 
-	ret = drm_colorop_curve_1d_lut_init(dev, ops[i], plane, MAX_COLOR_LUT_ENTRIES);
+	ret = drm_colorop_curve_1d_lut_init(dev, ops[i], plane, MAX_COLOR_LUT_ENTRIES,
+					    DRM_COLOROP_LUT1D_INTERPOLATION_LINEAR);
 	if (ret)
 		goto cleanup;
 
@@ -163,7 +164,8 @@ int amdgpu_dm_initialize_default_pipeline(struct drm_plane *plane, struct drm_pr
 		goto cleanup;
 	}
 
-	ret = drm_colorop_curve_1d_lut_init(dev, ops[i], plane, MAX_COLOR_LUT_ENTRIES);
+	ret = drm_colorop_curve_1d_lut_init(dev, ops[i], plane, MAX_COLOR_LUT_ENTRIES,
+					    DRM_COLOROP_LUT1D_INTERPOLATION_LINEAR);
 	if (ret)
 		goto cleanup;
 
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index a04f1c98fef9..9420fb9b8a46 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -795,6 +795,8 @@ static void drm_atomic_colorop_print_state(struct drm_printer *p,
 		break;
 	case DRM_COLOROP_1D_LUT:
 		drm_printf(p, "\tsize=%d\n", colorop->lut_size);
+		drm_printf(p, "\tinterpolation=%s\n",
+			   drm_get_colorop_lut1d_interpolation_name(colorop->lut1d_interpolation));
 		drm_printf(p, "\tdata blob id=%d\n", state->data ? state->data->base.id : 0);
 		break;
 	case DRM_COLOROP_CTM_3X4:
diff --git a/drivers/gpu/drm/drm_colorop.c b/drivers/gpu/drm/drm_colorop.c
index 45aa7b059e35..7360ca4d2325 100644
--- a/drivers/gpu/drm/drm_colorop.c
+++ b/drivers/gpu/drm/drm_colorop.c
@@ -78,6 +78,9 @@ static const char * const colorop_curve_1d_type_names[] = {
 	[DRM_COLOROP_1D_CURVE_PQ_125_INV_EOTF] = "PQ 125 Inverse EOTF",
 };
 
+static const struct drm_prop_enum_list drm_colorop_lut1d_interpolation_list[] = {
+	{ DRM_COLOROP_LUT1D_INTERPOLATION_LINEAR, "Linear" },
+};
 
 /* Init Helpers */
 
@@ -234,10 +237,12 @@ static int drm_colorop_create_data_prop(struct drm_device *dev, struct drm_color
  * @colorop: The drm_colorop object to initialize
  * @plane: The associated drm_plane
  * @lut_size: LUT size supported by driver
+ * @lut1d_interpolation: 1D LUT interpolation type
  * @return zero on success, -E value on failure
  */
 int drm_colorop_curve_1d_lut_init(struct drm_device *dev, struct drm_colorop *colorop,
-				  struct drm_plane *plane, uint32_t lut_size)
+				  struct drm_plane *plane, uint32_t lut_size,
+				  enum drm_colorop_lut1d_interpolation_type lut1d_interpolation)
 {
 	struct drm_property *prop;
 	int ret;
@@ -257,6 +262,17 @@ int drm_colorop_curve_1d_lut_init(struct drm_device *dev, struct drm_colorop *co
 	drm_object_attach_property(&colorop->base, colorop->lut_size_property, lut_size);
 	colorop->lut_size = lut_size;
 
+	/* Interpolation */
+	prop = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE, "LUT1D_INTERPOLATION",
+					drm_colorop_lut1d_interpolation_list,
+					ARRAY_SIZE(drm_colorop_lut1d_interpolation_list));
+	if (!prop)
+		return -ENOMEM;
+
+	colorop->lut1d_interpolation_property = prop;
+	drm_object_attach_property(&colorop->base, prop, lut1d_interpolation);
+	colorop->lut1d_interpolation = lut1d_interpolation;
+
 	/* data */
 	ret = drm_colorop_create_data_prop(dev, colorop);
 	if (ret)
@@ -411,6 +427,9 @@ static const char * const colorop_type_name[] = {
 	[DRM_COLOROP_CTM_3X4] = "3x4 Matrix",
 	[DRM_COLOROP_MULTIPLIER] = "Multiplier",
 };
+static const char * const colorop_lut1d_interpolation_name[] = {
+	[DRM_COLOROP_LUT1D_INTERPOLATION_LINEAR] = "Linear",
+};
 
 const char *drm_get_colorop_type_name(enum drm_colorop_type type)
 {
@@ -428,6 +447,21 @@ const char *drm_get_colorop_curve_1d_type_name(enum drm_colorop_curve_1d_type ty
 	return colorop_curve_1d_type_names[type];
 }
 
+/**
+ * drm_get_colorop_lut1d_interpolation_name: return a string for interpolation type
+ * @type: interpolation type to compute name of
+ *
+ * In contrast to the other drm_get_*_name functions this one here returns a
+ * const pointer and hence is threadsafe.
+ */
+const char *drm_get_colorop_lut1d_interpolation_name(enum drm_colorop_lut1d_interpolation_type type)
+{
+	if (WARN_ON(type >= ARRAY_SIZE(colorop_lut1d_interpolation_name)))
+		return "unknown";
+
+	return colorop_lut1d_interpolation_name[type];
+}
+
 /**
  * drm_colorop_set_next_property - sets the next pointer
  * @colorop: drm colorop
diff --git a/include/drm/drm_colorop.h b/include/drm/drm_colorop.h
index 159e6d52e8b1..86694d45d1d1 100644
--- a/include/drm/drm_colorop.h
+++ b/include/drm/drm_colorop.h
@@ -273,6 +273,21 @@ struct drm_colorop {
 	 */
 	uint32_t lut_size;
 
+	/**
+	 * @lut1d_interpolation:
+	 *
+	 * Read-only
+	 * Interpolation for DRM_COLOROP_1D_LUT
+	 */
+	enum drm_colorop_lut1d_interpolation_type lut1d_interpolation;
+
+	/**
+	 * @lut1d_interpolation_property:
+	 *
+	 * Read-only property for DRM_COLOROP_1D_LUT interpolation
+	 */
+	struct drm_property *lut1d_interpolation_property;
+
 	/**
 	 * @curve_1d_type_property:
 	 *
@@ -339,7 +354,8 @@ static inline struct drm_colorop *drm_colorop_find(struct drm_device *dev,
 int drm_colorop_curve_1d_init(struct drm_device *dev, struct drm_colorop *colorop,
 			      struct drm_plane *plane, u64 supported_tfs);
 int drm_colorop_curve_1d_lut_init(struct drm_device *dev, struct drm_colorop *colorop,
-				  struct drm_plane *plane, uint32_t lut_size);
+				  struct drm_plane *plane, uint32_t lut_size,
+				  enum drm_colorop_lut1d_interpolation_type lut1d_interpolation);
 int drm_colorop_ctm_3x4_init(struct drm_device *dev, struct drm_colorop *colorop,
 			     struct drm_plane *plane);
 int drm_colorop_mult_init(struct drm_device *dev, struct drm_colorop *colorop,
@@ -393,6 +409,7 @@ const char *drm_get_colorop_type_name(enum drm_colorop_type type);
  * const pointer and hence is threadsafe.
  */
 const char *drm_get_colorop_curve_1d_type_name(enum drm_colorop_curve_1d_type type);
+const char *drm_get_colorop_lut1d_interpolation_name(enum drm_colorop_lut1d_interpolation_type type);
 
 void drm_colorop_set_next_property(struct drm_colorop *colorop, struct drm_colorop *next);
 
diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
index fa5e1ddaf4f0..d76c8ffe5408 100644
--- a/include/uapi/drm/drm_mode.h
+++ b/include/uapi/drm/drm_mode.h
@@ -932,6 +932,19 @@ enum drm_colorop_type {
 	DRM_COLOROP_MULTIPLIER,
 };
 
+/**
+ * enum drm_colorop_lut1d_interpolation_type - type of interpolation for 1D LUTs
+ */
+enum drm_colorop_lut1d_interpolation_type {
+	/**
+	 * @DRM_COLOROP_LUT1D_INTERPOLATION_LINEAR:
+	 *
+	 * Linear interpolation. Values between points of the LUT will be
+	 * linearly interpolated.
+	 */
+	DRM_COLOROP_LUT1D_INTERPOLATION_LINEAR,
+};
+
 /**
  * struct drm_plane_size_hint - Plane size hints
  * @width: The width of the plane in pixel
-- 
2.43.0