linux/include/drm/drm_fourcc.h

/*
 * Copyright (c) 2016 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting documentation, and
 * that the name of the copyright holders not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  The copyright holders make no representations
 * about the suitability of this software for any purpose.  It is provided "as
 * is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 */
#ifndef __DRM_FOURCC_H__
#define __DRM_FOURCC_H__

#include <linux/types.h>
#include <uapi/drm/drm_fourcc.h>

/*
 * DRM formats are little endian.  Define host endian variants for the
 * most common formats here, to reduce the #ifdefs needed in drivers.
 *
 * Note that the DRM_FORMAT_BIG_ENDIAN flag should only be used in
 * case the format can't be specified otherwise, so we don't end up
 * with two values describing the same format.
 */
#ifdef __BIG_ENDIAN
# define DRM_FORMAT_HOST_XRGB1555     (DRM_FORMAT_XRGB1555         |	\
				       DRM_FORMAT_BIG_ENDIAN)
# define DRM_FORMAT_HOST_RGB565       (DRM_FORMAT_RGB565           |	\
				       DRM_FORMAT_BIG_ENDIAN)
# define DRM_FORMAT_HOST_XRGB8888     DRM_FORMAT_BGRX8888
# define DRM_FORMAT_HOST_ARGB8888     DRM_FORMAT_BGRA8888
#else
# define DRM_FORMAT_HOST_XRGB1555     DRM_FORMAT_XRGB1555
# define DRM_FORMAT_HOST_RGB565       DRM_FORMAT_RGB565
# define DRM_FORMAT_HOST_XRGB8888     DRM_FORMAT_XRGB8888
# define DRM_FORMAT_HOST_ARGB8888     DRM_FORMAT_ARGB8888
#endif

struct drm_device;
struct drm_mode_fb_cmd2;

/**
 * struct drm_format_info - information about a DRM format
 * @format: 4CC format identifier (DRM_FORMAT_*)
 * @depth: Color depth (number of bits per pixel excluding padding bits),
 *	valid for a subset of RGB formats only. This is a legacy field, do not
 *	use in new code and set to 0 for new formats.
 * @num_planes: Number of color planes (1 to 3)
 * @cpp: Number of bytes per pixel (per plane)
 * @hsub: Horizontal chroma subsampling factor
 * @vsub: Vertical chroma subsampling factor
 * @has_alpha: Does the format embeds an alpha component?
 * @is_yuv: Is it a YUV format?
 */
struct drm_format_info {
	u32 format;
	u8 depth;
	u8 num_planes;
	u8 cpp[3];
	u8 hsub;
	u8 vsub;
	bool has_alpha;
	bool is_yuv;
};

/**
 * struct drm_format_name_buf - name of a DRM format
 * @str: string buffer containing the format name
 */
struct drm_format_name_buf {
	char str[32];
};

const struct drm_format_info *__drm_format_info(u32 format);
const struct drm_format_info *drm_format_info(u32 format);
const struct drm_format_info *
drm_get_format_info(struct drm_device *dev,
		    const struct drm_mode_fb_cmd2 *mode_cmd);
uint32_t drm_mode_legacy_fb_format(uint32_t bpp, uint32_t depth);
uint32_t drm_driver_legacy_fb_format(struct drm_device *dev,
				     uint32_t bpp, uint32_t depth);
int drm_format_num_planes(uint32_t format);
int drm_format_plane_cpp(uint32_t format, int plane);
int drm_format_horz_chroma_subsampling(uint32_t format);
int drm_format_vert_chroma_subsampling(uint32_t format);
int drm_format_plane_width(int width, uint32_t format, int plane);
int drm_format_plane_height(int height, uint32_t format, int plane);
const char *drm_get_format_name(uint32_t format, struct drm_format_name_buf *buf);

#endif /* __DRM_FOURCC_H__ */