drm/i915: Fix CRT force detect on Cougarpoint
To make CRT force detect reliable on Cougarpoint, we need to
disable DAC before force detect, and restore back when trigger
is completed.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index 1f732ba..996d063 100644
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -157,15 +157,21 @@
{
struct drm_device *dev = connector->dev;
struct drm_i915_private *dev_priv = dev->dev_private;
- u32 adpa;
+ u32 adpa, temp;
bool ret;
- adpa = I915_READ(PCH_ADPA);
+ temp = adpa = I915_READ(PCH_ADPA);
- adpa &= ~ADPA_CRT_HOTPLUG_MASK;
- /* disable HPD first */
- I915_WRITE(PCH_ADPA, adpa);
- (void)I915_READ(PCH_ADPA);
+ if (HAS_PCH_CPT(dev)) {
+ /* Disable DAC before force detect */
+ I915_WRITE(PCH_ADPA, adpa & ~ADPA_DAC_ENABLE);
+ (void)I915_READ(PCH_ADPA);
+ } else {
+ adpa &= ~ADPA_CRT_HOTPLUG_MASK;
+ /* disable HPD first */
+ I915_WRITE(PCH_ADPA, adpa);
+ (void)I915_READ(PCH_ADPA);
+ }
adpa |= (ADPA_CRT_HOTPLUG_PERIOD_128 |
ADPA_CRT_HOTPLUG_WARMUP_10MS |
@@ -181,6 +187,11 @@
while ((I915_READ(PCH_ADPA) & ADPA_CRT_HOTPLUG_FORCE_TRIGGER) != 0)
;
+ if (HAS_PCH_CPT(dev)) {
+ I915_WRITE(PCH_ADPA, temp);
+ (void)I915_READ(PCH_ADPA);
+ }
+
/* Check the status to see if both blue and green are on now */
adpa = I915_READ(PCH_ADPA);
adpa &= ADPA_CRT_HOTPLUG_MONITOR_MASK;