From: Zheng Yang <zhengyang@rock-chips.com>
Date: Wed, 28 Jun 2017 02:58:36 +0000 (+0800)
Subject: drm/edid: Clear the old hdmi info before parsing display info
X-Git-Tag: release-20171130_firefly~4^2~287
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0637d2d637e7a923e59f7de19e3f032327dd0997;p=firefly-linux-kernel-4.4.55.git

drm/edid: Clear the old hdmi info before parsing display info

The current EDID might not support advanced HDMI 2.0 features.
Leaving old hdmi info in the drm_display_info will make display
work not okay, when switching display from HDMI 2.0 device to
HDMI 1.4 device.

Change-Id: Ifaf11a115580a93ec00160d54f0d453842d7b484
Signed-off-by: Zheng Yang <zhengyang@rock-chips.com>
---

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 615607da389b..3cd00c1a67cf 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -4212,6 +4212,8 @@ static void drm_add_display_info(struct drm_connector *connector,
 	info->max_tmds_clock = 0;
 	info->dvi_dual = false;
 
+	memset(&info->hdmi, 0, sizeof(info->hdmi));
+
 	if (edid->revision < 3)
 		return;