pixel_format.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2
  3#ifndef VIDEO_PIXEL_FORMAT_H
  4#define VIDEO_PIXEL_FORMAT_H
  5
  6struct pixel_format {
  7	unsigned char bits_per_pixel;
  8	bool indexed;
  9	union {
 10		struct {
 11			struct {
 12				unsigned char offset;
 13				unsigned char length;
 14			} alpha, red, green, blue;
 15		};
 16		struct {
 17			unsigned char offset;
 18			unsigned char length;
 19		} index;
 20	};
 21};
 22
 23#define PIXEL_FORMAT_C8 \
 24	{ 8, true, { .index = {0, 8}, } }
 25
 26#define PIXEL_FORMAT_XRGB1555 \
 27	{ 16, false, { .alpha = {0, 0}, .red = {10, 5}, .green = {5, 5}, .blue = {0, 5} } }
 28
 29#define PIXEL_FORMAT_RGB565 \
 30	{ 16, false, { .alpha = {0, 0}, .red = {11, 5}, .green = {5, 6}, .blue = {0, 5} } }
 31
 32#define PIXEL_FORMAT_RGB888 \
 33	{ 24, false, { .alpha = {0, 0}, .red = {16, 8}, .green = {8, 8}, .blue = {0, 8} } }
 34
 35#define PIXEL_FORMAT_XRGB8888 \
 36	{ 32, false, { .alpha = {0, 0}, .red = {16, 8}, .green = {8, 8}, .blue = {0, 8} } }
 37
 38#define PIXEL_FORMAT_XBGR8888 \
 39	{ 32, false, { .alpha = {0, 0}, .red = {0, 8}, .green = {8, 8}, .blue = {16, 8} } }
 40
 41#define PIXEL_FORMAT_XRGB2101010 \
 42	{ 32, false, { .alpha = {0, 0}, .red = {20, 10}, .green = {10, 10}, .blue = {0, 10} } }
 43
 44#define __pixel_format_cmp_field(lhs, rhs, name) \
 45	{ \
 46		int ret = ((lhs)->name) - ((rhs)->name); \
 47		if (ret) \
 48			return ret; \
 49	}
 50
 51#define __pixel_format_cmp_bitfield(lhs, rhs, name) \
 52	{ \
 53		__pixel_format_cmp_field(lhs, rhs, name.offset); \
 54		__pixel_format_cmp_field(lhs, rhs, name.length); \
 55	}
 56
 57/**
 58 * pixel_format_cmp - Compares two pixel-format descriptions
 59 *
 60 * @lhs: a pixel-format description
 61 * @rhs: a pixel-format description
 62 *
 63 * Compares two pixel-format descriptions for their order. The semantics
 64 * are equivalent to memcmp().
 65 *
 66 * Returns:
 67 * 0 if both arguments describe the same pixel format, less-than-zero if lhs < rhs,
 68 * or greater-than-zero if lhs > rhs.
 69 */
 70static inline int pixel_format_cmp(const struct pixel_format *lhs, const struct pixel_format *rhs)
 71{
 72	__pixel_format_cmp_field(lhs, rhs, bits_per_pixel);
 73	__pixel_format_cmp_field(lhs, rhs, indexed);
 74
 75	if (lhs->indexed) {
 76		__pixel_format_cmp_bitfield(lhs, rhs, index);
 77	} else {
 78		__pixel_format_cmp_bitfield(lhs, rhs, alpha);
 79		__pixel_format_cmp_bitfield(lhs, rhs, red);
 80		__pixel_format_cmp_bitfield(lhs, rhs, green);
 81		__pixel_format_cmp_bitfield(lhs, rhs, blue);
 82	}
 83
 84	return 0;
 85}
 86
 87/**
 88 * pixel_format_equal - Compares two pixel-format descriptions for equality
 89 *
 90 * @lhs: a pixel-format description
 91 * @rhs: a pixel-format description
 92 *
 93 * Returns:
 94 * True if both arguments describe the same pixel format, or false otherwise.
 95 */
 96static inline bool pixel_format_equal(const struct pixel_format *lhs,
 97				      const struct pixel_format *rhs)
 98{
 99	return !pixel_format_cmp(lhs, rhs);
100}
101
102#endif