[Intel-gfx] [PATCH 2/2]IGD: workaround i2c bus issue in gfx driver side

[Shaohua Li]

In IGD, DPCUNIT_CLOCK_GATE_DISABLE bit should be set, otherwise i2c
access will be wrong.

Signed-off-by: Shaohua Li <shaohua.li at intel.com>
---
 src/i830_driver.c |    5 +++++
 1 file changed, 5 insertions(+)

Index: xf86_video_intel/src/i830_driver.c
===================================================================
--- xf86_video_intel.orig/src/i830_driver.c
+++ xf86_video_intel/src/i830_driver.c
@@ -1057,6 +1057,11 @@ I830PreInitDDC(ScrnInfoPtr pScrn)
 	 pI830->ddc2 = FALSE;
       }
    }
+
+  if (IS_IGD(pI830)) {
+        /* Driver is using bit bashing for I2C, this bit should be set to 1 */
+        OUTREG(DSPCLK_GATE_D, INREG(DSPCLK_GATE_D) | DPCUNIT_CLOCK_GATE_DISABLE);
+    }
 }
 
 static void