drm/drm_crtc: Introduce sharpness strength property

Introduce a new crtc property "SHARPNESS_STRENGTH" that allows
the user to set the intensity so as to get the sharpness effect.
The value of this property can be set from 0-255.
It is useful in scenario when the output is blurry and user
want to sharpen the pixels. User can increase/decrease the
sharpness level depending on the content displayed.

v2: Rename crtc property variable [Arun]
Add modeset detail in uapi doc[Uma]
v3: Fix build issue
v4: Modify the subject line[Ankit]

Signed-off-by: Nemesa Garg <[e-mail]>
Reviewed-by: Ankit Nautiyal <[e-mail]>
Tested-by: Adarsh G M <[e-mail]>
Acked-by: Simona Vetter <[e-mail]>
Link: https://invent.kde.org/plasma/kwin/-/merge_requests/7689
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jani Nikula <[e-mail]>

drivers/gpu/drm/drm_atomic_uapi.c

···
 		set_out_fence_for_crtc(state->state, crtc, fence_ptr);
 	} else if (property == crtc->scaling_filter_property) {
 		state->scaling_filter = val;
+	} else if (property == crtc->sharpness_strength_property) {
+		state->sharpness_strength = val;
 	} else if (crtc->funcs->atomic_set_property) {
 		return crtc->funcs->atomic_set_property(crtc, state, property, val);
 	} else {
···
 		*val = 0;
 	else if (property == crtc->scaling_filter_property)
 		*val = state->scaling_filter;
+	else if (property == crtc->sharpness_strength_property)
+		*val = state->sharpness_strength;
 	else if (crtc->funcs->atomic_get_property)
 		return crtc->funcs->atomic_get_property(crtc, state, property, val);
 	else {

drivers/gpu/drm/drm_crtc.c

···
  * 		Driver's default scaling filter
  * 	Nearest Neighbor:
  * 		Nearest Neighbor scaling filter
+ * SHARPNESS_STRENGTH:
+ *	Atomic property for setting the sharpness strength/intensity by userspace.
+ *
+ *	The value of this property is set as an integer value ranging
+ *	from 0 - 255 where:
+ *
+ *	0: Sharpness feature is disabled(default value).
+ *
+ *	1: Minimum sharpness.
+ *
+ *	255: Maximum sharpness.
+ *
+ *	User can gradually increase or decrease the sharpness level and can
+ *	set the optimum value depending on content.
+ *	This value will be passed to kernel through the UAPI.
+ *	The setting of this property does not require modeset.
+ *	The sharpness effect takes place post blending on the final composed output.
+ *	If the feature is disabled, the content remains same without any sharpening effect
+ *	and when this feature is applied, it enhances the clarity of the content.
  */
 
 __printf(6, 0)
···
 	return 0;
 }
 EXPORT_SYMBOL(drm_crtc_create_scaling_filter_property);
+
+int drm_crtc_create_sharpness_strength_property(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct drm_property *prop =
+		drm_property_create_range(dev, 0, "SHARPNESS_STRENGTH", 0, 255);
+
+	if (!prop)
+		return -ENOMEM;
+
+	crtc->sharpness_strength_property = prop;
+	drm_object_attach_property(&crtc->base, prop, 0);
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_crtc_create_sharpness_strength_property);
 
 /**
  * drm_crtc_in_clone_mode - check if the given CRTC state is in clone mode

include/drm/drm_crtc.h

···
 	enum drm_scaling_filter scaling_filter;
 
 	/**
+	 * @sharpness_strength:
+	 *
+	 * Used by the user to set the sharpness intensity.
+	 * The value ranges from 0-255.
+	 * Default value is 0 which disable the sharpness feature.
+	 * Any value greater than 0 enables sharpening with the
+	 * specified strength.
+	 */
+	u8 sharpness_strength;
+
+	/**
 	 * @event:
 	 *
 	 * Optional pointer to a DRM event to signal upon completion of the
···
 	struct drm_property *scaling_filter_property;
 
 	/**
+	 * @sharpness_strength_property: property to apply
+	 * the intensity of the sharpness requested.
+	 */
+	struct drm_property *sharpness_strength_property;
+
+	/**
 	 * @state:
 	 *
 	 * Current atomic state for this CRTC.
···
 int drm_crtc_create_scaling_filter_property(struct drm_crtc *crtc,
 					    unsigned int supported_filters);
 bool drm_crtc_in_clone_mode(struct drm_crtc_state *crtc_state);
+int drm_crtc_create_sharpness_strength_property(struct drm_crtc *crtc);
 #endif /* __DRM_CRTC_H__ */