@@ -372,6 +372,13 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
return -ENOMEM;
dev->mode_config.modifiers_property = prop;
+ prop = drm_property_create(dev,
+ DRM_MODE_PROP_IMMUTABLE | DRM_MODE_PROP_BLOB,
+ "SIZE_HINTS", 0);
+ if (!prop)
+ return -ENOMEM;
+ dev->mode_config.size_hints_property = prop;
+
return 0;
}
@@ -140,6 +140,25 @@
* DRM_FORMAT_MOD_LINEAR. Before linux kernel release v5.1 there have been
* various bugs in this area with inconsistencies between the capability
* flag and per-plane properties.
+ *
+ * SIZE_HINTS:
+ * Blob property which contains the set of recommended plane size
+ * which can used for simple "cursor like" use cases (eg. no scaling).
+ * Using these hints frees userspace from extensive probing of
+ * supported plane sizes through atomic/setcursor ioctls.
+ *
+ * The blob contains an array of struct drm_plane_size_hint, in
+ * order of preference. For optimal usage userspace should pick
+ * the first size that satisfies its own requirements.
+ *
+ * Drivers should only attach this property to planes that
+ * support a very limited set of sizes.
+ *
+ * Note that property value 0 (ie. no blob) is reserved for potential
+ * future use. Current userspace is expected to ignore the property
+ * if the value is 0, and fall back to some other means (eg.
+ * &DRM_CAP_CURSOR_WIDTH and &DRM_CAP_CURSOR_HEIGHT) to determine
+ * the appropriate plane size to use.
*/
static unsigned int drm_num_planes(struct drm_device *dev)
@@ -1729,3 +1748,40 @@ int drm_plane_create_scaling_filter_property(struct drm_plane *plane,
return 0;
}
EXPORT_SYMBOL(drm_plane_create_scaling_filter_property);
+
+/**
+ * drm_plane_add_size_hint_property - create a size hint property
+ *
+ * @plane: drm plane
+ * @hints: size hints
+ * @num_hints: number of size hints
+ *
+ * Create a size hints property for the plane.
+ *
+ * RETURNS:
+ * Zero for success or -errno
+ */
+int drm_plane_add_size_hints_property(struct drm_plane *plane,
+ const struct drm_plane_size_hint *hints,
+ int num_hints)
+{
+ struct drm_device *dev = plane->dev;
+ struct drm_mode_config *config = &dev->mode_config;
+ struct drm_property_blob *blob;
+
+ /* extending to other plane types needs actual thought */
+ if (drm_WARN_ON(dev, plane->type != DRM_PLANE_TYPE_CURSOR))
+ return -EINVAL;
+
+ blob = drm_property_create_blob(dev,
+ array_size(sizeof(hints[0]), num_hints),
+ hints);
+ if (IS_ERR(blob))
+ return PTR_ERR(blob);
+
+ drm_object_attach_property(&plane->base, config->size_hints_property,
+ blob->base.id);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_plane_add_size_hints_property);
@@ -942,6 +942,11 @@ struct drm_mode_config {
*/
struct drm_property *modifiers_property;
+ /**
+ * @size_hints_propertty: Plane SIZE_HINTS property.
+ */
+ struct drm_property *size_hints_property;
+
/* cursor size */
uint32_t cursor_width, cursor_height;
@@ -32,6 +32,7 @@
#include <drm/drm_util.h>
struct drm_crtc;
+struct drm_plane_size_hint;
struct drm_printer;
struct drm_modeset_acquire_ctx;
@@ -976,5 +977,8 @@ drm_plane_get_damage_clips(const struct drm_plane_state *state);
int drm_plane_create_scaling_filter_property(struct drm_plane *plane,
unsigned int supported_filters);
+int drm_plane_add_size_hints_property(struct drm_plane *plane,
+ const struct drm_plane_size_hint *hints,
+ int num_hints);
#endif
@@ -865,6 +865,17 @@ struct drm_color_lut {
__u16 reserved;
};
+/**
+ * struct drm_plane_size_hint - Plane size hints
+ *
+ * The plane SIZE_HINTS property blob contains an
+ * array of struct drm_plane_size_hint.
+ */
+struct drm_plane_size_hint {
+ __u16 width;
+ __u16 height;
+};
+
/**
* struct hdr_metadata_infoframe - HDR Metadata Infoframe Data.
*