Commit 11a8d095 authored by Jani Nikula's avatar Jani Nikula
Browse files

drm/edid: abstract cea data block collection size 



Add a function to get the cea data block collection size.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
Reviewed-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/5339ab3249400a3c41001967e7ff2611b58e0425.1654674560.git.jani.nikula@intel.com
parent fc67615f

drivers/gpu/drm/drm_edid.c

+21 −3
Original line number Diff line number Diff line
@@ -4482,6 +4482,20 @@ __cea_db_iter_current_block(const struct cea_db_iter *iter) 
	return NULL;

}



/*

 * References:

 * - CTA-861-H section 7.3.3 CTA Extension Version 3

 */

static int cea_db_collection_size(const u8 *cta)

{

	u8 d = cta[2];



	if (d < 4 || d > 127)

		return 0;



	return d - 4;

}



/*

 * References:

 * - VESA E-EDID v1.4
@@ -4492,15 +4506,19 @@ static const void *__cea_db_iter_edid_next(struct cea_db_iter *iter) 
	const u8 *ext;



	drm_edid_iter_for_each(ext, &iter->edid_iter) {

		int size;



		/* Only support CTA Extension revision 3+ */

		if (ext[0] != CEA_EXT || cea_revision(ext) < 3)

			continue;



		iter->index = 4;

		iter->end = ext[2];

		if (iter->end < 4 || iter->end > 127)

		size = cea_db_collection_size(ext);

		if (!size)

			continue;



		iter->index = 4;

		iter->end = iter->index + size;



		return ext;

	}