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// SPDX-License-Identifier: GPL-2.0 OR MIT
/**************************************************************************
*
* Copyright (c) 2018 VMware, Inc., Palo Alto, CA., USA
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
* USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* Authors:
* Deepak Rawat <drawat@vmware.com>
*
**************************************************************************/
#include <drm/drm_damage_helper.h>
/**
* DOC: overview
*
* FB_DAMAGE_CLIPS is an optional plane property which provides a means to
* specify a list of damage rectangles on a plane in framebuffer coordinates of
* the framebuffer attached to the plane. In current context damage is the area
* of plane framebuffer that has changed since last plane update (also called
* page-flip), irrespective of whether currently attached framebuffer is same as
* framebuffer attached during last plane update or not.
*
* FB_DAMAGE_CLIPS is a hint to kernel which could be helpful for some drivers
* to optimize internally especially for virtual devices where each framebuffer
* change needs to be transmitted over network, usb, etc.
*
* Since FB_DAMAGE_CLIPS is a hint so it is an optional property. User-space can
* ignore damage clips property and in that case driver will do a full plane
* update. In case damage clips are provided then it is guaranteed that the area
* inside damage clips will be updated to plane. For efficiency driver can do
* full update or can update more than specified in damage clips. Since driver
* is free to read more, user-space must always render the entire visible
* framebuffer. Otherwise there can be corruptions. Also, if a user-space
* provides damage clips which doesn't encompass the actual damage to
* framebuffer (since last plane update) can result in incorrect rendering.
*
* FB_DAMAGE_CLIPS is a blob property with the layout of blob data is simply an
* array of &drm_mode_rect. Unlike plane &drm_plane_state.src coordinates,
* damage clips are not in 16.16 fixed point. Similar to plane src in
* framebuffer, damage clips cannot be negative. In damage clip, x1/y1 are
* inclusive and x2/y2 are exclusive. While kernel does not error for overlapped
* damage clips, it is strongly discouraged.
*
* Drivers that are interested in damage interface for plane should enable
* FB_DAMAGE_CLIPS property by calling drm_plane_enable_fb_damage_clips().
*/
/**
* drm_plane_enable_fb_damage_clips - Enables plane fb damage clips property.
* @plane: Plane on which to enable damage clips property.
*
* This function lets driver to enable the damage clips property on a plane.
*/
void drm_plane_enable_fb_damage_clips(struct drm_plane *plane)
{
struct drm_device *dev = plane->dev;
struct drm_mode_config *config = &dev->mode_config;
drm_object_attach_property(&plane->base, config->prop_fb_damage_clips,
0);
}
EXPORT_SYMBOL(drm_plane_enable_fb_damage_clips);
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