[Intel-gfx] [PATCH 18/26] drm/i915: add ValleyView specific CRT detect function

[Jesse Barnes]

Might be able to merge this back in at some point, but we're seeing bugs
with ADPA based detection, so keep it separate for now with explicit
hotplug trigger usage.

v2: drop superfluous debug message

Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
---
 drivers/gpu/drm/i915/intel_crt.c |   38 ++++++++++++++++++++++++++++++++++++++
 1 files changed, 38 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index 4d3d736..0d50df8 100644
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -212,6 +212,41 @@ static bool intel_ironlake_crt_detect_hotplug(struct drm_connector *connector)
 	return ret;
 }
 
+static bool valleyview_crt_detect_hotplug(struct drm_connector *connector)
+{
+	struct drm_device *dev = connector->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	u32 adpa;
+	bool ret;
+	u32 save_adpa;
+
+	save_adpa = adpa = I915_READ(ADPA);
+	DRM_DEBUG_KMS("trigger hotplug detect cycle: adpa=0x%x\n", adpa);
+
+	adpa |= ADPA_CRT_HOTPLUG_FORCE_TRIGGER;
+
+	I915_WRITE(ADPA, adpa);
+
+	if (wait_for((I915_READ(ADPA) & ADPA_CRT_HOTPLUG_FORCE_TRIGGER) == 0,
+		     1000)) {
+		DRM_DEBUG_KMS("timed out waiting for FORCE_TRIGGER");
+		I915_WRITE(ADPA, save_adpa);
+	}
+
+	/* Check the status to see if both blue and green are on now */
+	adpa = I915_READ(ADPA);
+	if ((adpa & ADPA_CRT_HOTPLUG_MONITOR_MASK) != 0)
+		ret = true;
+	else
+		ret = false;
+
+	DRM_DEBUG_KMS("valleyview hotplug adpa=0x%x, result %d\n", adpa, ret);
+
+	ret = true;
+
+	return ret;
+}
+
 /**
  * Uses CRT_HOTPLUG_EN and CRT_HOTPLUG_STAT to detect CRT presence.
  *
@@ -231,6 +266,9 @@ static bool intel_crt_detect_hotplug(struct drm_connector *connector)
 	if (HAS_PCH_SPLIT(dev))
 		return intel_ironlake_crt_detect_hotplug(connector);
 
+	if (IS_VALLEYVIEW(dev))
+		return valleyview_crt_detect_hotplug(connector);
+
 	/*
 	 * On 4 series desktop, CRT detect sequence need to be done twice
 	 * to get a reliable result.
-- 
1.7.5.4