[Intel-gfx] [PATCH 03/15] drm/i915: Don't get hw state from DVO chip unless DVO is enabled

[ville.syrjala at linux.intel.com]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Certain DVO chips (ns2501 for example) don't like to be accessed unless
the PLL is running. Simply skip the DVO get_hw_state if the DVO port
is disabled.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_dvo.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_dvo.c b/drivers/gpu/drm/i915/intel_dvo.c
index a3631c0..5d7d975 100644
--- a/drivers/gpu/drm/i915/intel_dvo.c
+++ b/drivers/gpu/drm/i915/intel_dvo.c
@@ -112,7 +112,15 @@ static struct intel_dvo *intel_attached_dvo(struct drm_connector *connector)
 
 static bool intel_dvo_connector_get_hw_state(struct intel_connector *connector)
 {
+	struct drm_device *dev = connector->base.dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_dvo *intel_dvo = intel_attached_dvo(&connector->base);
+	u32 tmp;
+
+	tmp = I915_READ(intel_dvo->dev.dvo_reg);
+
+	if (!(tmp & DVO_ENABLE))
+		return false;
 
 	return intel_dvo->dev.dev_ops->get_hw_state(&intel_dvo->dev);
 }
-- 
1.8.5.5