[RFC 4/9] drm/drm_color_mgmt: add function to create 3D LUT modes supported

[Jacopo Mondi <jacopo.mondi@xxxxxxxxxxxxxxxx>]

From: Melissa Wen <mwen@xxxxxxxxxx>

DRM color function to create modes for lut3d mode property from an array
of drm_color_lut3d_mode modes supported by the HW and advertise to
userspace. Userspace can get the description of a specific mode in the
enum list from its blob data.

Signed-off-by: Melissa Wen <mwen@xxxxxxxxxx>
---
 drivers/gpu/drm/drm_color_mgmt.c | 43 +++++++++++++++++++++++++++++++-
 include/drm/drm_color_mgmt.h     |  4 +++
 2 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_color_mgmt.c b/drivers/gpu/drm/drm_color_mgmt.c
index f92633b3b67e..6ce48007cdd4 100644
--- a/drivers/gpu/drm/drm_color_mgmt.c
+++ b/drivers/gpu/drm/drm_color_mgmt.c
@@ -104,7 +104,7 @@
  *	LUT3D property. A mode specifies size, stride, bit depth and color
  *	format and depends on the underlying hardware). If drivers support
  *	multiple 3D LUT modes, they should be declared in a array of
- *	drm_color_lut3d_mode and they will be advertised as an enum.
+ *	drm_mode_lut3d_mode and they will be advertised as an enum.
  *
  * “GAMMA_LUT”:
  *	Blob property to set the gamma lookup table (LUT) mapping pixel data
@@ -228,6 +228,47 @@ void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
 }
 EXPORT_SYMBOL(drm_crtc_enable_color_mgmt);
 
+int drm_crtc_create_lut3d_mode_property(struct drm_crtc *crtc,
+					const struct drm_mode_lut3d_mode modes[],
+					unsigned int num_modes)
+{
+	struct drm_device *dev = crtc->dev;
+	struct drm_property_blob *blob;
+	struct drm_property *prop;
+	char *name;
+	int ret;
+
+	if (dev->mode_config.lut3d_mode_property)
+		return 0;
+
+	prop = drm_property_create(dev, DRM_MODE_PROP_ENUM, "LUT3D_MODE", num_modes);
+	if (!prop)
+		return -EINVAL;
+
+	for (int i = 0; i < num_modes; i++) {
+		blob = drm_property_create_blob(dev, sizeof(modes[i]), &modes[i]);
+		if (IS_ERR(blob))
+			return PTR_ERR(blob);
+
+		name = kasprintf(GFP_KERNEL, "lut3d_%d_%dbit",
+				 modes[i].lut_size, modes[i].bit_depth);
+		if (!name)
+			return -ENOMEM;
+
+		ret = drm_property_add_enum(prop, blob->base.id, name);
+		if (ret) {
+			drm_property_blob_put(blob);
+			kfree(name);
+			return ret;
+		}
+		kfree(name);
+	}
+	dev->mode_config.lut3d_mode_property = prop;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_crtc_create_lut3d_mode_property);
+
 /**
  * drm_mode_crtc_set_gamma_size - set the gamma table size
  * @crtc: CRTC to set the gamma table size for
diff --git a/include/drm/drm_color_mgmt.h b/include/drm/drm_color_mgmt.h
index 81c298488b0c..af9305925572 100644
--- a/include/drm/drm_color_mgmt.h
+++ b/include/drm/drm_color_mgmt.h
@@ -59,6 +59,10 @@ void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
 				bool has_ctm,
 				uint gamma_lut_size);
 
+int drm_crtc_create_lut3d_mode_property(struct drm_crtc *crtc,
+					const struct drm_mode_lut3d_mode modes[],
+					unsigned int num_modes);
+
 int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
 				 int gamma_size);
 
-- 
2.40.1