From 27dbefb911f2650f473eb98b5de79e88f6559c64 Mon Sep 17 00:00:00 2001
From: Jani Nikula <jani.nikula@intel.com>
Date: Thu, 6 Apr 2017 16:44:17 +0300
Subject: [PATCH] drm/i915/dp: read sink count to a temporary variable first
Mime-version: 1.0
Content-type: text/plain; charset=UTF-8
Content-transfer-encoding: 8bit
Git-commit: 27dbefb911f2650f473eb98b5de79e88f6559c64
Patch-mainline: v4.13-rc1
References: FATE#322643 bsc#1055900
Don't clobber intel_dp->sink_count with the raw value.
Suggested-by: Ville Syrj채l채 <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrj채l채 <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/37d3222115172922fcd5ab038238359935bd561f.1491485983.git.jani.nikula@intel.com
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/i915/intel_dp.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -3702,6 +3702,8 @@ intel_edp_init_dpcd(struct intel_dp *int
static bool
intel_dp_get_dpcd(struct intel_dp *intel_dp)
{
+ u8 sink_count;
+
if (!intel_dp_read_dpcd(intel_dp))
return false;
@@ -3711,8 +3713,7 @@ intel_dp_get_dpcd(struct intel_dp *intel
intel_dp_set_common_rates(intel_dp);
}
- if (drm_dp_dpcd_readb(&intel_dp->aux, DP_SINK_COUNT,
- &intel_dp->sink_count) <= 0)
+ if (drm_dp_dpcd_readb(&intel_dp->aux, DP_SINK_COUNT, &sink_count) <= 0)
return false;
/*
@@ -3720,7 +3721,7 @@ intel_dp_get_dpcd(struct intel_dp *intel
* a member variable in intel_dp will track any changes
* between short pulse interrupts.
*/
- intel_dp->sink_count = DP_GET_SINK_COUNT(intel_dp->sink_count);
+ intel_dp->sink_count = DP_GET_SINK_COUNT(sink_count);
/*
* SINK_COUNT == 0 and DOWNSTREAM_PORT_PRESENT == 1 implies that