From 99016646608148be3cf3df157a60f83447dc45aa Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak@intel.com>
Date: Wed, 10 May 2017 12:21:49 +0300
Subject: [PATCH] drm/i915/sdvo: Check error return from intel_sdvo_get_value()
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Git-commit: 99016646608148be3cf3df157a60f83447dc45aa
Patch-mainline: v4.13-rc1
References: FATE#322643 bsc#1055900

The current code assumes that 'enhancements' won't change in case of an
error, but this isn't guaranteed. Fix things by treating any error as a
lack of the given capability.

V2: 
- Remove the now redundant init of enhancements. (Ville)

Cc: Ville Syrj채l채 <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrj채l채 <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1494408113-379-3-git-send-email-imre.deak@intel.com
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/i915/intel_sdvo.c |    9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

--- a/drivers/gpu/drm/i915/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/intel_sdvo.c
@@ -2875,11 +2875,10 @@ static bool intel_sdvo_create_enhance_pr
 
 	BUILD_BUG_ON(sizeof(enhancements) != 2);
 
-	enhancements.response = 0;
-	intel_sdvo_get_value(intel_sdvo,
-			     SDVO_CMD_GET_SUPPORTED_ENHANCEMENTS,
-			     &enhancements, sizeof(enhancements));
-	if (enhancements.response == 0) {
+	if (!intel_sdvo_get_value(intel_sdvo,
+				  SDVO_CMD_GET_SUPPORTED_ENHANCEMENTS,
+				  &enhancements, sizeof(enhancements)) ||
+	    enhancements.response == 0) {
 		DRM_DEBUG_KMS("No enhancement is supported\n");
 		return true;
 	}