[PATCH] drm/edid: Allow non-fatal checksum errors in CEA blocks

[Adam Jackson]

Switches will try to update the topology address and not correctly fix
up the checksum, so just let it slide.

https://bugs.freedesktop.org/28229

Signed-off-by: Adam Jackson <ajax at redhat.com>
---
 drivers/gpu/drm/drm_edid.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index f569ae8..c198186 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -147,7 +147,10 @@ drm_edid_block_valid(u8 *raw_edid)
 		csum += raw_edid[i];
 	if (csum) {
 		DRM_ERROR("EDID checksum is invalid, remainder is %d\n", csum);
-		goto bad;
+
+		/* allow CEA to slide through, switches mangle this */
+		if (raw_edid[0] != 0x02)
+			goto bad;
 	}
 
 	/* per-block-type checks */
-- 
1.7.0.1