LP_OUTPUT_HOLD is only in MIPI_PORT_CTRL(PORT_A) even for PORT_C in case of dual link. In the dual link implementation, the bit is correctly set or unset for hardcoded PORT_A, but for bit update the register base value is read by using MIPI_PORT_CTRL(port) in a loop. The second iteration will read base value from PORT_C and program for PORT_A. Mostly in case of dual link all other bit values should be same, but logically we should read from PORT_A. So hardcode to read initial value from PORT_A as well. Signed-off-by: Shobhit Kumar <shobhit.kumar@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_dsi.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c index 6857d19..3fe8a1e 100644 --- a/drivers/gpu/drm/i915/intel_dsi.c +++ b/drivers/gpu/drm/i915/intel_dsi.c @@ -177,12 +177,11 @@ static void intel_dsi_device_ready(struct intel_encoder *encoder) I915_WRITE(MIPI_DEVICE_READY(port), ULPS_STATE_ENTER); usleep_range(2500, 3000); - val = I915_READ(MIPI_PORT_CTRL(port)); - /* Enable MIPI PHY transparent latch * Common bit for both MIPI Port A & MIPI Port C * No similar bit in MIPI Port C reg */ + val = I915_READ(MIPI_PORT_CTRL(PORT_A)); I915_WRITE(MIPI_PORT_CTRL(PORT_A), val | LP_OUTPUT_HOLD); usleep_range(1000, 1500); @@ -360,10 +359,10 @@ static void intel_dsi_clear_device_ready(struct intel_encoder *encoder) == 0x00000), 30)) DRM_ERROR("DSI LP not going Low\n"); - val = I915_READ(MIPI_PORT_CTRL(port)); /* Disable MIPI PHY transparent latch * Common bit for both MIPI Port A & MIPI Port C */ + val = I915_READ(MIPI_PORT_CTRL(PORT_A)); I915_WRITE(MIPI_PORT_CTRL(PORT_A), val & ~LP_OUTPUT_HOLD); usleep_range(1000, 1500); -- 1.9.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx