[Intel-gfx] [PATCH] drm/i915/lvds: Kill trying to probe LVDS using a DDC write

[Chris Wilson]

This fails on the Macbook for example, and Jesse reported a failure
after unloading and reloading the i915.ko module on a HP system. It
looked promising distinguishing several of the ghost LVDS, but with even
a single false positive, it cannot replace the quirk table.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Jesse Barnes <jbarnes at virtuousgeek.org>
---
 drivers/gpu/drm/i915/intel_lvds.c |   24 ------------------------
 1 files changed, 0 insertions(+), 24 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 86cd30b..a562bd2 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -829,25 +829,6 @@ static bool lvds_is_present_in_vbt(struct drm_device *dev,
 	return false;
 }
 
-static bool intel_lvds_ddc_probe(struct drm_device *dev, u8 pin)
-{
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	u8 buf = 0;
-	struct i2c_msg msgs[] = {
-		{
-			.addr = 0xA0,
-			.flags = 0,
-			.len = 1,
-			.buf = &buf,
-		},
-	};
-	struct i2c_adapter *i2c = &dev_priv->gmbus[pin].adapter;
-	/* XXX this only appears to work when using GMBUS */
-	if (intel_gmbus_is_forced_bit(i2c))
-		return true;
-	return i2c_transfer(i2c, msgs, 1) == 1;
-}
-
 /**
  * intel_lvds_init - setup LVDS connectors on this device
  * @dev: drm device
@@ -888,11 +869,6 @@ bool intel_lvds_init(struct drm_device *dev)
 		}
 	}
 
-	if (!intel_lvds_ddc_probe(dev, pin)) {
-		DRM_DEBUG_KMS("LVDS did not respond to DDC probe\n");
-		return false;
-	}
-
 	intel_lvds = kzalloc(sizeof(struct intel_lvds), GFP_KERNEL);
 	if (!intel_lvds) {
 		return false;
-- 
1.7.4.1