[PATCHv3 02/10] drm/crtc: Expose API to create drm crtc property for histogram

[Arun R Murthy <arun.r.murthy@intel.com>]

Add drm-crtc property for histogram and for the properties added add
corresponding get/set_property.

Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
---
 drivers/gpu/drm/drm_atomic_state_helper.c |  6 ++
 drivers/gpu/drm/drm_atomic_uapi.c         | 17 +++++
 drivers/gpu/drm/drm_crtc.c                | 84 +++++++++++++++++++++++
 include/drm/drm_crtc.h                    |  1 +
 4 files changed, 108 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c
index 519228eb1095..3b2b58e36a6d 100644
--- a/drivers/gpu/drm/drm_atomic_state_helper.c
+++ b/drivers/gpu/drm/drm_atomic_state_helper.c
@@ -143,6 +143,8 @@ void __drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc,
 		drm_property_blob_get(state->ctm);
 	if (state->gamma_lut)
 		drm_property_blob_get(state->gamma_lut);
+	if (state->histogram_data)
+		drm_property_blob_get(state->histogram_data);
 	state->mode_changed = false;
 	state->active_changed = false;
 	state->planes_changed = false;
@@ -156,6 +158,8 @@ void __drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc,
 	/* Self refresh should be canceled when a new update is available */
 	state->active = drm_atomic_crtc_effectively_active(state);
 	state->self_refresh_active = false;
+
+	state->histogram_iet_updated = false;
 }
 EXPORT_SYMBOL(__drm_atomic_helper_crtc_duplicate_state);
 
@@ -215,6 +219,8 @@ void __drm_atomic_helper_crtc_destroy_state(struct drm_crtc_state *state)
 	drm_property_blob_put(state->degamma_lut);
 	drm_property_blob_put(state->ctm);
 	drm_property_blob_put(state->gamma_lut);
+	if (state->histogram_data)
+		drm_property_blob_put(state->histogram_data);
 }
 EXPORT_SYMBOL(__drm_atomic_helper_crtc_destroy_state);
 
diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
index 370dc676e3aa..b3c13c0fafae 100644
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -415,6 +415,17 @@ static int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
 			return -EFAULT;
 
 		set_out_fence_for_crtc(state->state, crtc, fence_ptr);
+	} else if (property == crtc->histogram_enable_property) {
+		state->histogram_enable = val;
+	} else if (property == crtc->histogram_iet_property) {
+		ret = drm_property_replace_blob_from_id(dev,
+							&state->histogram_iet,
+							val,
+							-1,
+							sizeof(struct drm_iet),
+							&replaced);
+		state->histogram_iet_updated |= replaced;
+		return ret;
 	} else if (property == crtc->scaling_filter_property) {
 		state->scaling_filter = val;
 	} else if (crtc->funcs->atomic_set_property) {
@@ -452,6 +463,12 @@ drm_atomic_crtc_get_property(struct drm_crtc *crtc,
 		*val = (state->gamma_lut) ? state->gamma_lut->base.id : 0;
 	else if (property == config->prop_out_fence_ptr)
 		*val = 0;
+	else if (property == crtc->histogram_enable_property)
+		*val = state->histogram_enable;
+	else if (property == crtc->histogram_data_property)
+		*val = (state->histogram_data) ? state->histogram_data->base.id : 0;
+	else if (property == crtc->histogram_iet_property)
+		*val = (state->histogram_iet) ? state->histogram_iet->base.id : 0;
 	else if (property == crtc->scaling_filter_property)
 		*val = state->scaling_filter;
 	else if (crtc->funcs->atomic_get_property)
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 3488ff067c69..8fedf6684eb3 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -939,3 +939,87 @@ int drm_crtc_create_scaling_filter_property(struct drm_crtc *crtc,
 	return 0;
 }
 EXPORT_SYMBOL(drm_crtc_create_scaling_filter_property);
+
+/**
+ * drm_crtc_create_histogram_property: create histogram properties
+ *
+ * @crtc: pointer tot he struct drm_crtc.
+ *
+ * The property HISTOGRAM_ENABLE allows user to enable/disable the
+ * histogram feature in the hardware. Upon KMD enabling by writing to the
+ * hardware registers, a histogram is generated. Histogram is composed of
+ * 'n' bins with each bin being an integer(pixel count).
+ * An event HISTOGRAM will be sent to the user. User upon recieving this
+ * event user can read the hardware generated histogram using crtc property
+ * HISTOGRAM_DATA. User can use this histogram data, apply various
+ * equilization techniques to come up with a pixel factor. This pixel
+ * factor is an array of integer with 'n+1' elements. This is fed back to
+ * the KMD by crtc property HISTOGRAM_IET. KMD will write this IET data
+ * back to the hardware to see the enhancement/equilization done to the
+ * images on that pipe.
+ * The crtc property HISTOGRAM_DATA and HISTOGRAM_IET is of type blob.
+ *
+ * For crtc property HISTOGRAM_DATA,
+ * the blob data pointer will be the address of the struct drm_histogram.
+ * struct drm_histogram {
+ *         u64 data_ptr;
+ *         u32 nr_elements;
+ * }
+ * Histogram is composed of @nr_elements of bins with each bin being an
+ * integer value, referred to as pixel_count.
+ * The element @data_ptr holds the address of histogam.
+ * Sample:
+ * Historgram[0] = 2050717
+ * Historgram[1] = 244619
+ * Historgram[2] = 173368
+ * ....
+ * Historgram[31] = 21631
+ *
+ * For crtc_property HISTOGRAM_IET,
+ * the blob data pointer will be the address of the struct drm_iet.
+ *  struct drm_iet {
+ *         u64 data_ptr;
+ *         u32 nr_elements;
+ * }
+ * ImageEnhancemenT(IET) is composed of @nr_elements of bins with each bin
+ * being an integer value, referred to as pixel factor.
+ * The element @data_ptr holds the addess of pixel factor.
+ * Sample:
+ * Pixel Factor[0] = 1023
+ * Pixel Factor[1] = 695
+ * Pixel Factor[2] = 1023
+ * ....
+ * Pixel Factor[32] = 512
+ *
+ * RETURNS:
+ * Zero for success or -errno
+ */
+int drm_crtc_create_histogram_property(struct drm_crtc *crtc)
+{
+	struct drm_property *prop;
+
+	prop = drm_property_create_bool(crtc->dev, DRM_MODE_PROP_ATOMIC,
+					"HISTOGRAM_ENABLE");
+	if (!prop)
+		return -ENOMEM;
+	drm_object_attach_property(&crtc->base, prop, 0);
+	crtc->histogram_enable_property = prop;
+
+	prop = drm_property_create(crtc->dev, DRM_MODE_PROP_ATOMIC |
+				   DRM_MODE_PROP_IMMUTABLE | DRM_MODE_PROP_BLOB,
+				   "HISTOGRAM_DATA", 0);
+	if (!prop)
+		return -ENOMEM;
+	drm_object_attach_property(&crtc->base, prop, 0);
+	crtc->histogram_data_property = prop;
+
+	prop = drm_property_create(crtc->dev, DRM_MODE_PROP_ATOMIC |
+				   DRM_MODE_PROP_BLOB, "HISTOGRAM_IET", 0);
+	if (!prop)
+		return -ENOMEM;
+	drm_object_attach_property(&crtc->base, prop, 0);
+	crtc->histogram_iet_property = prop;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_crtc_create_histogram_property);
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index f0f4a73e2e31..c3807e371160 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -1374,5 +1374,6 @@ static inline struct drm_crtc *drm_crtc_find(struct drm_device *dev,
 
 int drm_crtc_create_scaling_filter_property(struct drm_crtc *crtc,
 					    unsigned int supported_filters);
+int drm_crtc_create_histogram_property(struct drm_crtc *crtc);
 
 #endif /* __DRM_CRTC_H__ */
-- 
2.25.1