3 files changed, 34 insertions, 8 deletions

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_drv.c b/drivers/gpu/drm/radeon/radeon_drv.c
index e8545be7d584..6864682e91a7 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..2a9cd7be9aad 100644
--- a/drivers/gpu/drm/radeon/radeon_encoders.c
+++ b/drivers/gpu/drm/radeon/radeon_encoders.c
@@ -158,10 +158,36 @@ 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) {
+                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 +200,8 @@ 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);
                         }
                 }
         }