diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 88913a4..a69a3d0 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3754,17 +3754,6 @@
 			continue;
 		}
 
-		if (intel_encoder->type == INTEL_OUTPUT_EDP) {
-			/* Use VBT settings if we have an eDP panel */
-			unsigned int edp_bpc = dev_priv->edp.bpp / 3;
-
-			if (edp_bpc < display_bpc) {
-				DRM_DEBUG_KMS("clamping display bpc (was %d) to eDP (%d)\n", display_bpc, edp_bpc);
-				display_bpc = edp_bpc;
-			}
-			continue;
-		}
-
 		/* Not one of the known troublemakers, check the EDID */
 		list_for_each_entry(connector, &dev->mode_config.connector_list,
 				    head) {
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 0a56b9a..a6c426a 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1174,10 +1174,14 @@
 	WARN(!intel_dp->want_panel_vdd, "Need VDD to turn off panel\n");
 
 	pp = ironlake_get_pp_control(dev_priv);
-	pp &= ~(POWER_TARGET_ON | PANEL_POWER_RESET | EDP_BLC_ENABLE);
+	/* We need to switch off panel power _and_ force vdd, for otherwise some
+	 * panels get very unhappy and cease to work. */
+	pp &= ~(POWER_TARGET_ON | EDP_FORCE_VDD | PANEL_POWER_RESET | EDP_BLC_ENABLE);
 	I915_WRITE(PCH_PP_CONTROL, pp);
 	POSTING_READ(PCH_PP_CONTROL);
 
+	intel_dp->want_panel_vdd = false;
+
 	ironlake_wait_panel_off(intel_dp);
 }
 
@@ -1287,11 +1291,9 @@
 	 * ensure that we have vdd while we switch off the panel. */
 	ironlake_edp_panel_vdd_on(intel_dp);
 	ironlake_edp_backlight_off(intel_dp);
-	ironlake_edp_panel_off(intel_dp);
-
 	intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
+	ironlake_edp_panel_off(intel_dp);
 	intel_dp_link_down(intel_dp);
-	ironlake_edp_panel_vdd_off(intel_dp, false);
 }
 
 static void intel_dp_commit(struct drm_encoder *encoder)
@@ -1326,11 +1328,9 @@
 		/* Switching the panel off requires vdd. */
 		ironlake_edp_panel_vdd_on(intel_dp);
 		ironlake_edp_backlight_off(intel_dp);
-		ironlake_edp_panel_off(intel_dp);
-
 		intel_dp_sink_dpms(intel_dp, mode);
+		ironlake_edp_panel_off(intel_dp);
 		intel_dp_link_down(intel_dp);
-		ironlake_edp_panel_vdd_off(intel_dp, false);
 
 		if (is_cpu_edp(intel_dp))
 			ironlake_edp_pll_off(encoder);
diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c
index d79500b..b9755f6 100644
--- a/drivers/gpu/drm/i915/intel_i2c.c
+++ b/drivers/gpu/drm/i915/intel_i2c.c
@@ -486,9 +486,6 @@
 		bus->dev_priv = dev_priv;
 
 		bus->adapter.algo = &gmbus_algorithm;
-		ret = i2c_add_adapter(&bus->adapter);
-		if (ret)
-			goto err;
 
 		/* By default use a conservative clock rate */
 		bus->reg0 = port | GMBUS_RATE_100KHZ;
@@ -498,6 +495,10 @@
 			bus->force_bit = true;
 
 		intel_gpio_setup(bus, port);
+
+		ret = i2c_add_adapter(&bus->adapter);
+		if (ret)
+			goto err;
 	}
 
 	intel_i2c_reset(dev_priv->dev);
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 9474488d..3df4f5f 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -311,9 +311,6 @@
 	if (dev_priv->backlight_level == 0)
 		dev_priv->backlight_level = intel_panel_get_max_backlight(dev);
 
-	dev_priv->backlight_enabled = true;
-	intel_panel_actually_set_backlight(dev, dev_priv->backlight_level);
-
 	if (INTEL_INFO(dev)->gen >= 4) {
 		uint32_t reg, tmp;
 
@@ -326,7 +323,7 @@
 		 * we don't track the backlight dpms state, hence check whether
 		 * we have to do anything first. */
 		if (tmp & BLM_PWM_ENABLE)
-			return;
+			goto set_level;
 
 		if (dev_priv->num_pipe == 3)
 			tmp &= ~BLM_PIPE_SELECT_IVB;
@@ -347,6 +344,14 @@
 			I915_WRITE(BLC_PWM_PCH_CTL1, tmp);
 		}
 	}
+
+set_level:
+	/* Call below after setting BLC_PWM_CPU_CTL2 and BLC_PWM_PCH_CTL1.
+	 * BLC_PWM_CPU_CTL may be cleared to zero automatically when these
+	 * registers are set.
+	 */
+	dev_priv->backlight_enabled = true;
+	intel_panel_actually_set_backlight(dev, dev_priv->backlight_level);
 }
 
 static void intel_panel_init_backlight(struct drm_device *dev)
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 414af1e..e2a73b3 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -227,31 +227,36 @@
 	 * number of bits based on the write domains has little performance
 	 * impact.
 	 */
-	flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
-	flags |= PIPE_CONTROL_TLB_INVALIDATE;
-	flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
-	flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
-	flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
-	flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
-	flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
-	flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
-	/*
-	 * Ensure that any following seqno writes only happen when the render
-	 * cache is indeed flushed (but only if the caller actually wants that).
-	 */
-	if (flush_domains)
+	if (flush_domains) {
+		flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
+		flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
+		/*
+		 * Ensure that any following seqno writes only happen
+		 * when the render cache is indeed flushed.
+		 */
 		flags |= PIPE_CONTROL_CS_STALL;
+	}
+	if (invalidate_domains) {
+		flags |= PIPE_CONTROL_TLB_INVALIDATE;
+		flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
+		flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
+		flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
+		flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
+		flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
+		/*
+		 * TLB invalidate requires a post-sync write.
+		 */
+		flags |= PIPE_CONTROL_QW_WRITE;
+	}
 
-	ret = intel_ring_begin(ring, 6);
+	ret = intel_ring_begin(ring, 4);
 	if (ret)
 		return ret;
 
-	intel_ring_emit(ring, GFX_OP_PIPE_CONTROL(5));
+	intel_ring_emit(ring, GFX_OP_PIPE_CONTROL(4));
 	intel_ring_emit(ring, flags);
 	intel_ring_emit(ring, scratch_addr | PIPE_CONTROL_GLOBAL_GTT);
-	intel_ring_emit(ring, 0); /* lower dword */
-	intel_ring_emit(ring, 0); /* uppwer dword */
-	intel_ring_emit(ring, MI_NOOP);
+	intel_ring_emit(ring, 0);
 	intel_ring_advance(ring);
 
 	return 0;