drm/i915: Remove DAC disable in CRT force detect on IGDNG

commit 730915d65f9e763de9dc26c5f1b8abaae775b243 upstream.

This is not required on newer stepping hardware to get
reliable force detect status. Removing this fixes screen
blank flicker in CRT detect on IGDNG.

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index 590f81c8f59482b6e702d8b8191211e79cd8987b..5ae4c1a8847c88a3c277c442c924417765ea1951 100644 (file)
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -151,13 +151,10 @@ static bool intel_igdng_crt_detect_hotplug(struct drm_connector *connector)
 {
        struct drm_device *dev = connector->dev;
        struct drm_i915_private *dev_priv = dev->dev_private;
-       u32 adpa, temp;
+       u32 adpa;
        bool ret;
 
-       temp = adpa = I915_READ(PCH_ADPA);
-
-       adpa &= ~ADPA_DAC_ENABLE;
-       I915_WRITE(PCH_ADPA, adpa);
+       adpa = I915_READ(PCH_ADPA);
 
        adpa &= ~ADPA_CRT_HOTPLUG_MASK;
 
@@ -184,8 +181,6 @@ static bool intel_igdng_crt_detect_hotplug(struct drm_connector *connector)
        else
                ret = false;
 
-       /* restore origin register */
-       I915_WRITE(PCH_ADPA, temp);
        return ret;
 }