drm/nouveau: Fix backlight control on PPC machines with an internal TMDS panel.

This commit fixes fdo bug 29685.

Reported-by: Vlado Plaga <rechner@vlado-do.de>
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/nv04_dfp.c b/drivers/gpu/drm/nouveau/nv04_dfp.c
index ea89f6e69d4c..0d3206a7046c 100644
--- a/drivers/gpu/drm/nouveau/nv04_dfp.c
+++ b/drivers/gpu/drm/nouveau/nv04_dfp.c
@@ -475,6 +475,27 @@ static void nv04_dfp_commit(struct drm_encoder *encoder)
                 nv_crtc->index, '@' + ffs(nv_encoder->dcb->or));
 }
 
+static void nv04_dfp_update_backlight(struct drm_encoder *encoder, int mode)
+{
+#ifdef __powerpc__
+        struct drm_device *dev = encoder->dev;
+
+        /* BIOS scripts usually take care of the backlight, thanks
+         * Apple for your consistency.
+         */
+        if (dev->pci_device == 0x0179 || dev->pci_device == 0x0189 ||
+            dev->pci_device == 0x0329) {
+                if (mode == DRM_MODE_DPMS_ON) {
+                        nv_mask(dev, NV_PBUS_DEBUG_DUALHEAD_CTL, 0, 1 << 31);
+                        nv_mask(dev, NV_PCRTC_GPIO_EXT, 3, 1);
+                } else {
+                        nv_mask(dev, NV_PBUS_DEBUG_DUALHEAD_CTL, 1 << 31, 0);
+                        nv_mask(dev, NV_PCRTC_GPIO_EXT, 3, 0);
+                }
+        }
+#endif
+}
+
 static inline bool is_powersaving_dpms(int mode)
 {
         return (mode != DRM_MODE_DPMS_ON);
@@ -522,6 +543,7 @@ static void nv04_lvds_dpms(struct drm_encoder *encoder, int mode)
                                          LVDS_PANEL_OFF, 0);
         }
 
+        nv04_dfp_update_backlight(encoder, mode);
         nv04_dfp_update_fp_control(encoder, mode);
 
         if (mode == DRM_MODE_DPMS_ON)
@@ -545,6 +567,7 @@ static void nv04_tmds_dpms(struct drm_encoder *encoder, int mode)
         NV_INFO(dev, "Setting dpms mode %d on tmds encoder (output %d)\n",
                      mode, nv_encoder->dcb->index);
 
+        nv04_dfp_update_backlight(encoder, mode);
         nv04_dfp_update_fp_control(encoder, mode);
 }