From a327feeef44108000c171ea2d74f4ab33c09bad7 Mon Sep 17 00:00:00 2001 From: Jernej Skrabec Date: Thu, 22 Apr 2021 01:14:29 +0100 Subject: [PATCH] common: edid: Search for valid timing in extension block One of my monitors have only 4k@60 timing in base EDID block which is out of range for devices with HDMI 1.4. It turns out that it has additional detailed timings in CTA-861 Extension Block and two of them are appropriate for HDMI 1.4. Add additional search for valid detailed timing in extension block. Signed-off-by: Jernej Skrabec Acked-by: Andre Przywara Signed-off-by: Andre Przywara --- common/edid.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/common/edid.c b/common/edid.c index a6c875d9c8..fa85bcd6a1 100644 --- a/common/edid.c +++ b/common/edid.c @@ -220,6 +220,24 @@ int edid_get_timing_validate(u8 *buf, int buf_size, /* Look for detailed timing in base EDID */ found = edid_find_valid_timing(edid->monitor_details.descriptor, 4, timing, mode_valid, mode_valid_priv); + + /* Look for detailed timing in CTA-861 Extension Block */ + if (!found && edid->extension_flag && buf_size >= EDID_EXT_SIZE) { + struct edid_cea861_info *info = + (struct edid_cea861_info *)(buf + sizeof(*edid)); + + if (info->extension_tag == EDID_CEA861_EXTENSION_TAG) { + int count = EDID_CEA861_DTD_COUNT(*info); + int offset = info->dtd_offset; + int size = count * sizeof(struct edid_detailed_timing); + + if (offset >= 4 && offset + size < EDID_SIZE) + found = edid_find_valid_timing( + (u8 *)info + offset, count, timing, + mode_valid, mode_valid_priv); + } + } + if (!found) return -EINVAL;