Commit cff5fb82 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

video: pixel_format: Add compare helpers 



Add helpers that compare two pixel-format descriptions against
each other.

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250714151513.309475-2-tzimmermann@suse.de
parent cbdd16b8

include/video/pixel_format.h

+58 −0
Original line number Diff line number Diff line
@@ -38,4 +38,62 @@ struct pixel_format { 
#define PIXEL_FORMAT_XRGB2101010 \

	{ 32, false, { .alpha = {0, 0}, .red = {20, 10}, .green = {10, 10}, .blue = {0, 10} } }



#define __pixel_format_cmp_field(lhs, rhs, name) \

	{ \

		int ret = ((lhs)->name) - ((rhs)->name); \

		if (ret) \

			return ret; \

	}



#define __pixel_format_cmp_bitfield(lhs, rhs, name) \

	{ \

		__pixel_format_cmp_field(lhs, rhs, name.offset); \

		__pixel_format_cmp_field(lhs, rhs, name.length); \

	}



/**

 * pixel_format_cmp - Compares two pixel-format descriptions

 *

 * @lhs: a pixel-format description

 * @rhs: a pixel-format description

 *

 * Compares two pixel-format descriptions for their order. The semantics

 * are equivalent to memcmp().

 *

 * Returns:

 * 0 if both arguments describe the same pixel format, less-than-zero if lhs < rhs,

 * or greater-than-zero if lhs > rhs.

 */

static inline int pixel_format_cmp(const struct pixel_format *lhs, const struct pixel_format *rhs)

{

	__pixel_format_cmp_field(lhs, rhs, bits_per_pixel);

	__pixel_format_cmp_field(lhs, rhs, indexed);



	if (lhs->indexed) {

		__pixel_format_cmp_bitfield(lhs, rhs, index);

	} else {

		__pixel_format_cmp_bitfield(lhs, rhs, alpha);

		__pixel_format_cmp_bitfield(lhs, rhs, red);

		__pixel_format_cmp_bitfield(lhs, rhs, green);

		__pixel_format_cmp_bitfield(lhs, rhs, blue);

	}



	return 0;

}



/**

 * pixel_format_equal - Compares two pixel-format descriptions for equality

 *

 * @lhs: a pixel-format description

 * @rhs: a pixel-format description

 *

 * Returns:

 * True if both arguments describe the same pixel format, or false otherwise.

 */

static inline bool pixel_format_equal(const struct pixel_format *lhs,

				      const struct pixel_format *rhs)

{

	return !pixel_format_cmp(lhs, rhs);

}



#endif