diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c
index fa9565957f9d..3d546c606b43 100644
--- a/drivers/gpu/drm/radeon/cik.c
+++ b/drivers/gpu/drm/radeon/cik.c
@@ -4803,7 +4803,7 @@ struct bonaire_mqd
  */
 static int cik_cp_compute_resume(struct radeon_device *rdev)
 {
-	int r, i, idx;
+	int r, i, j, idx;
 	u32 tmp;
 	bool use_doorbell = true;
 	u64 hqd_gpu_addr;
@@ -4922,7 +4922,7 @@ static int cik_cp_compute_resume(struct radeon_device *rdev)
 		mqd->queue_state.cp_hqd_pq_wptr= 0;
 		if (RREG32(CP_HQD_ACTIVE) & 1) {
 			WREG32(CP_HQD_DEQUEUE_REQUEST, 1);
-			for (i = 0; i < rdev->usec_timeout; i++) {
+			for (j = 0; j < rdev->usec_timeout; j++) {
 				if (!(RREG32(CP_HQD_ACTIVE) & 1))
 					break;
 				udelay(1);
@@ -7751,17 +7751,17 @@ static inline u32 cik_get_ih_wptr(struct radeon_device *rdev)
 		wptr = RREG32(IH_RB_WPTR);
 
 	if (wptr & RB_OVERFLOW) {
+		wptr &= ~RB_OVERFLOW;
 		/* When a ring buffer overflow happen start parsing interrupt
 		 * from the last not overwritten vector (wptr + 16). Hopefully
 		 * this should allow us to catchup.
 		 */
-		dev_warn(rdev->dev, "IH ring buffer overflow (0x%08X, %d, %d)\n",
-			wptr, rdev->ih.rptr, (wptr + 16) + rdev->ih.ptr_mask);
+		dev_warn(rdev->dev, "IH ring buffer overflow (0x%08X, 0x%08X, 0x%08X)\n",
+			 wptr, rdev->ih.rptr, (wptr + 16) & rdev->ih.ptr_mask);
 		rdev->ih.rptr = (wptr + 16) & rdev->ih.ptr_mask;
 		tmp = RREG32(IH_RB_CNTL);
 		tmp |= IH_WPTR_OVERFLOW_CLEAR;
 		WREG32(IH_RB_CNTL, tmp);
-		wptr &= ~RB_OVERFLOW;
 	}
 	return (wptr & rdev->ih.ptr_mask);
 }
@@ -8251,6 +8251,7 @@ int cik_irq_process(struct radeon_device *rdev)
 		/* wptr/rptr are in bytes! */
 		rptr += 16;
 		rptr &= rdev->ih.ptr_mask;
+		WREG32(IH_RB_RPTR, rptr);
 	}
 	if (queue_hotplug)
 		schedule_work(&rdev->hotplug_work);
@@ -8259,7 +8260,6 @@ int cik_irq_process(struct radeon_device *rdev)
 	if (queue_thermal)
 		schedule_work(&rdev->pm.dpm.thermal.work);
 	rdev->ih.rptr = rptr;
-	WREG32(IH_RB_RPTR, rdev->ih.rptr);
 	atomic_set(&rdev->ih.lock, 0);
 
 	/* make sure wptr hasn't changed while processing */
diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index dbca60c7d097..e50807c29f69 100644
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -4749,17 +4749,17 @@ static u32 evergreen_get_ih_wptr(struct radeon_device *rdev)
 		wptr = RREG32(IH_RB_WPTR);
 
 	if (wptr & RB_OVERFLOW) {
+		wptr &= ~RB_OVERFLOW;
 		/* When a ring buffer overflow happen start parsing interrupt
 		 * from the last not overwritten vector (wptr + 16). Hopefully
 		 * this should allow us to catchup.
 		 */
-		dev_warn(rdev->dev, "IH ring buffer overflow (0x%08X, %d, %d)\n",
-			wptr, rdev->ih.rptr, (wptr + 16) + rdev->ih.ptr_mask);
+		dev_warn(rdev->dev, "IH ring buffer overflow (0x%08X, 0x%08X, 0x%08X)\n",
+			 wptr, rdev->ih.rptr, (wptr + 16) & rdev->ih.ptr_mask);
 		rdev->ih.rptr = (wptr + 16) & rdev->ih.ptr_mask;
 		tmp = RREG32(IH_RB_CNTL);
 		tmp |= IH_WPTR_OVERFLOW_CLEAR;
 		WREG32(IH_RB_CNTL, tmp);
-		wptr &= ~RB_OVERFLOW;
 	}
 	return (wptr & rdev->ih.ptr_mask);
 }
@@ -5137,6 +5137,7 @@ int evergreen_irq_process(struct radeon_device *rdev)
 		/* wptr/rptr are in bytes! */
 		rptr += 16;
 		rptr &= rdev->ih.ptr_mask;
+		WREG32(IH_RB_RPTR, rptr);
 	}
 	if (queue_hotplug)
 		schedule_work(&rdev->hotplug_work);
@@ -5145,7 +5146,6 @@ int evergreen_irq_process(struct radeon_device *rdev)
 	if (queue_thermal && rdev->pm.dpm_enabled)
 		schedule_work(&rdev->pm.dpm.thermal.work);
 	rdev->ih.rptr = rptr;
-	WREG32(IH_RB_RPTR, rdev->ih.rptr);
 	atomic_set(&rdev->ih.lock, 0);
 
 	/* make sure wptr hasn't changed while processing */
diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index 3cfb50056f7a..ea5c9af722ef 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -3792,17 +3792,17 @@ static u32 r600_get_ih_wptr(struct radeon_device *rdev)
 		wptr = RREG32(IH_RB_WPTR);
 
 	if (wptr & RB_OVERFLOW) {
+		wptr &= ~RB_OVERFLOW;
 		/* When a ring buffer overflow happen start parsing interrupt
 		 * from the last not overwritten vector (wptr + 16). Hopefully
 		 * this should allow us to catchup.
 		 */
-		dev_warn(rdev->dev, "IH ring buffer overflow (0x%08X, %d, %d)\n",
-			wptr, rdev->ih.rptr, (wptr + 16) + rdev->ih.ptr_mask);
+		dev_warn(rdev->dev, "IH ring buffer overflow (0x%08X, 0x%08X, 0x%08X)\n",
+			 wptr, rdev->ih.rptr, (wptr + 16) & rdev->ih.ptr_mask);
 		rdev->ih.rptr = (wptr + 16) & rdev->ih.ptr_mask;
 		tmp = RREG32(IH_RB_CNTL);
 		tmp |= IH_WPTR_OVERFLOW_CLEAR;
 		WREG32(IH_RB_CNTL, tmp);
-		wptr &= ~RB_OVERFLOW;
 	}
 	return (wptr & rdev->ih.ptr_mask);
 }
@@ -4048,6 +4048,7 @@ int r600_irq_process(struct radeon_device *rdev)
 		/* wptr/rptr are in bytes! */
 		rptr += 16;
 		rptr &= rdev->ih.ptr_mask;
+		WREG32(IH_RB_RPTR, rptr);
 	}
 	if (queue_hotplug)
 		schedule_work(&rdev->hotplug_work);
@@ -4056,7 +4057,6 @@ int r600_irq_process(struct radeon_device *rdev)
 	if (queue_thermal && rdev->pm.dpm_enabled)
 		schedule_work(&rdev->pm.dpm.thermal.work);
 	rdev->ih.rptr = rptr;
-	WREG32(IH_RB_RPTR, rdev->ih.rptr);
 	atomic_set(&rdev->ih.lock, 0);
 
 	/* make sure wptr hasn't changed while processing */
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index 5f05b4c84338..3247bfd14410 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -106,6 +106,7 @@ extern int radeon_vm_block_size;
 extern int radeon_deep_color;
 extern int radeon_use_pflipirq;
 extern int radeon_bapm;
+extern int radeon_backlight;
 
 /*
  * Copy from radeon_drv.h so we don't have to include both and have conflicting
diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index 75223dd3a8a3..12c8329644c4 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -123,6 +123,10 @@ static struct radeon_px_quirk radeon_px_quirk_list[] = {
 	 * https://bugzilla.kernel.org/show_bug.cgi?id=51381
 	 */
 	{ PCI_VENDOR_ID_ATI, 0x6741, 0x1043, 0x108c, RADEON_PX_QUIRK_DISABLE_PX },
+	/* Asus K53TK laptop with AMD A6-3420M APU and Radeon 7670m GPU
+	 * https://bugzilla.kernel.org/show_bug.cgi?id=51381
+	 */
+	{ PCI_VENDOR_ID_ATI, 0x6840, 0x1043, 0x2122, RADEON_PX_QUIRK_DISABLE_PX },
 	/* macbook pro 8.2 */
 	{ PCI_VENDOR_ID_ATI, 0x6741, PCI_VENDOR_ID_APPLE, 0x00e2, RADEON_PX_QUIRK_LONG_WAKEUP },
 	{ 0, 0, 0, 0, 0 },
diff --git a/drivers/gpu/drm/radeon/radeon_drv.c b/drivers/gpu/drm/radeon/radeon_drv.c
index 4126fd0937a2..f9d17b29b343 100644
--- a/drivers/gpu/drm/radeon/radeon_drv.c
+++ b/drivers/gpu/drm/radeon/radeon_drv.c
@@ -181,6 +181,7 @@ int radeon_vm_block_size = -1;
 int radeon_deep_color = 0;
 int radeon_use_pflipirq = 2;
 int radeon_bapm = -1;
+int radeon_backlight = -1;
 
 MODULE_PARM_DESC(no_wb, "Disable AGP writeback for scratch registers");
 module_param_named(no_wb, radeon_no_wb, int, 0444);
@@ -263,6 +264,9 @@ module_param_named(use_pflipirq, radeon_use_pflipirq, int, 0444);
 MODULE_PARM_DESC(bapm, "BAPM support (1 = enable, 0 = disable, -1 = auto)");
 module_param_named(bapm, radeon_bapm, int, 0444);
 
+MODULE_PARM_DESC(backlight, "backlight support (1 = enable, 0 = disable, -1 = auto)");
+module_param_named(backlight, radeon_backlight, int, 0444);
+
 static struct pci_device_id pciidlist[] = {
 	radeon_PCI_IDS
 };
diff --git a/drivers/gpu/drm/radeon/radeon_encoders.c b/drivers/gpu/drm/radeon/radeon_encoders.c
index 3c2094c25b53..15edf23b465c 100644
--- a/drivers/gpu/drm/radeon/radeon_encoders.c
+++ b/drivers/gpu/drm/radeon/radeon_encoders.c
@@ -158,10 +158,43 @@ radeon_get_encoder_enum(struct drm_device *dev, uint32_t supported_device, uint8
 	return ret;
 }
 
+static void radeon_encoder_add_backlight(struct radeon_encoder *radeon_encoder,
+					 struct drm_connector *connector)
+{
+	struct drm_device *dev = radeon_encoder->base.dev;
+	struct radeon_device *rdev = dev->dev_private;
+	bool use_bl = false;
+
+	if (!(radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT)))
+		return;
+
+	if (radeon_backlight == 0) {
+		return;
+	} else if (radeon_backlight == 1) {
+		use_bl = true;
+	} else if (radeon_backlight == -1) {
+		/* Quirks */
+		/* Amilo Xi 2550 only works with acpi bl */
+		if ((rdev->pdev->device == 0x9583) &&
+		    (rdev->pdev->subsystem_vendor == 0x1734) &&
+		    (rdev->pdev->subsystem_device == 0x1107))
+			use_bl = false;
+		else
+			use_bl = true;
+	}
+
+	if (use_bl) {
+		if (rdev->is_atom_bios)
+			radeon_atom_backlight_init(radeon_encoder, connector);
+		else
+			radeon_legacy_backlight_init(radeon_encoder, connector);
+		rdev->mode_info.bl_encoder = radeon_encoder;
+	}
+}
+
 void
 radeon_link_encoder_connector(struct drm_device *dev)
 {
-	struct radeon_device *rdev = dev->dev_private;
 	struct drm_connector *connector;
 	struct radeon_connector *radeon_connector;
 	struct drm_encoder *encoder;
@@ -174,13 +207,8 @@ radeon_link_encoder_connector(struct drm_device *dev)
 			radeon_encoder = to_radeon_encoder(encoder);
 			if (radeon_encoder->devices & radeon_connector->devices) {
 				drm_mode_connector_attach_encoder(connector, encoder);
-				if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT)) {
-					if (rdev->is_atom_bios)
-						radeon_atom_backlight_init(radeon_encoder, connector);
-					else
-						radeon_legacy_backlight_init(radeon_encoder, connector);
-					rdev->mode_info.bl_encoder = radeon_encoder;
-				}
+				if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT))
+					radeon_encoder_add_backlight(radeon_encoder, connector);
 			}
 		}
 	}
diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index 6bce40847753..3a0b973e8a96 100644
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -6316,17 +6316,17 @@ static inline u32 si_get_ih_wptr(struct radeon_device *rdev)
 		wptr = RREG32(IH_RB_WPTR);
 
 	if (wptr & RB_OVERFLOW) {
+		wptr &= ~RB_OVERFLOW;
 		/* When a ring buffer overflow happen start parsing interrupt
 		 * from the last not overwritten vector (wptr + 16). Hopefully
 		 * this should allow us to catchup.
 		 */
-		dev_warn(rdev->dev, "IH ring buffer overflow (0x%08X, %d, %d)\n",
-			wptr, rdev->ih.rptr, (wptr + 16) + rdev->ih.ptr_mask);
+		dev_warn(rdev->dev, "IH ring buffer overflow (0x%08X, 0x%08X, 0x%08X)\n",
+			 wptr, rdev->ih.rptr, (wptr + 16) & rdev->ih.ptr_mask);
 		rdev->ih.rptr = (wptr + 16) & rdev->ih.ptr_mask;
 		tmp = RREG32(IH_RB_CNTL);
 		tmp |= IH_WPTR_OVERFLOW_CLEAR;
 		WREG32(IH_RB_CNTL, tmp);
-		wptr &= ~RB_OVERFLOW;
 	}
 	return (wptr & rdev->ih.ptr_mask);
 }
@@ -6664,13 +6664,13 @@ int si_irq_process(struct radeon_device *rdev)
 		/* wptr/rptr are in bytes! */
 		rptr += 16;
 		rptr &= rdev->ih.ptr_mask;
+		WREG32(IH_RB_RPTR, rptr);
 	}
 	if (queue_hotplug)
 		schedule_work(&rdev->hotplug_work);
 	if (queue_thermal && rdev->pm.dpm_enabled)
 		schedule_work(&rdev->pm.dpm.thermal.work);
 	rdev->ih.rptr = rptr;
-	WREG32(IH_RB_RPTR, rdev->ih.rptr);
 	atomic_set(&rdev->ih.lock, 0);
 
 	/* make sure wptr hasn't changed while processing */