Re: [RFC v2 1/5] video: Add generic display entity core

Hi,

On 2012-11-22 23:45, Laurent Pinchart wrote:

+/**
+ * display_entity_get_modes - Get video modes supported by the display entity
+ * @entity The display entity
+ * @modes: Pointer to an array of modes
+ *
+ * Fill the modes argument with a pointer to an array of video modes. The array
+ * is owned by the display entity.
+ *
+ * Return the number of supported modes on success (including 0 if no mode is
+ * supported) or a negative error code otherwise.
+ */
+int display_entity_get_modes(struct display_entity *entity,
+			     const struct videomode **modes)
+{
+	if (!entity->ops.ctrl || !entity->ops.ctrl->get_modes)
+		return 0;
+
+	return entity->ops.ctrl->get_modes(entity, modes);
+}
+EXPORT_SYMBOL_GPL(display_entity_get_modes);
+
+/**
+ * display_entity_get_size - Get display entity physical size
+ * @entity: The display entity
+ * @width: Physical width in millimeters
+ * @height: Physical height in millimeters
+ *
+ * When applicable, for instance for display panels, retrieve the display
+ * physical size in millimeters.
+ *
+ * Return 0 on success or a negative error code otherwise.
+ */
+int display_entity_get_size(struct display_entity *entity,
+			    unsigned int *width, unsigned int *height)
+{
+	if (!entity->ops.ctrl || !entity->ops.ctrl->get_size)
+		return -EOPNOTSUPP;
+
+	return entity->ops.ctrl->get_size(entity, width, height);
+}
+EXPORT_SYMBOL_GPL(display_entity_get_size);

How do you envision these to be used with, say, DVI monitors with EDID
data? Should each panel driver, that manages a device with EDID, read
and parse the EDID itself? I guess that shouldn't be too difficult with
a common EDID lib, but that will only expose some of the information
found from EDID. Should the upper levels also have a way to get the raw
EDID data, in addition to funcs like above?

 Tomi