1 files changed, 51 insertions, 2 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 1aac59e83bff..5d4266115311 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -717,6 +717,51 @@ intel_dp_mode_set(struct drm_encoder *encoder, struct drm_display_mode *mode,
         }
 }
 
+static void ironlake_edp_panel_on (struct drm_device *dev)
+{
+        struct drm_i915_private *dev_priv = dev->dev_private;
+        unsigned long timeout = jiffies + msecs_to_jiffies(5000);
+        u32 pp, pp_status;
+
+        pp_status = I915_READ(PCH_PP_STATUS);
+        if (pp_status & PP_ON)
+                return;
+
+        pp = I915_READ(PCH_PP_CONTROL);
+        pp |= PANEL_UNLOCK_REGS | POWER_TARGET_ON;
+        I915_WRITE(PCH_PP_CONTROL, pp);
+        do {
+                pp_status = I915_READ(PCH_PP_STATUS);
+        } while (((pp_status & PP_ON) == 0) && !time_after(jiffies, timeout));
+
+        if (time_after(jiffies, timeout))
+                DRM_DEBUG_KMS("panel on wait timed out: 0x%08x\n", pp_status);
+
+        pp &= ~(PANEL_UNLOCK_REGS | EDP_FORCE_VDD);
+        I915_WRITE(PCH_PP_CONTROL, pp);
+}
+
+static void ironlake_edp_panel_off (struct drm_device *dev)
+{
+        struct drm_i915_private *dev_priv = dev->dev_private;
+        unsigned long timeout = jiffies + msecs_to_jiffies(5000);
+        u32 pp, pp_status;
+
+        pp = I915_READ(PCH_PP_CONTROL);
+        pp &= ~POWER_TARGET_ON;
+        I915_WRITE(PCH_PP_CONTROL, pp);
+        do {
+                pp_status = I915_READ(PCH_PP_STATUS);
+        } while ((pp_status & PP_ON) && !time_after(jiffies, timeout));
+
+        if (time_after(jiffies, timeout))
+                DRM_DEBUG_KMS("panel off wait timed out\n");
+
+        /* Make sure VDD is enabled so DP AUX will work */
+        pp |= EDP_FORCE_VDD;
+        I915_WRITE(PCH_PP_CONTROL, pp);
+}
+
 static void ironlake_edp_backlight_on (struct drm_device *dev)
 {
         struct drm_i915_private *dev_priv = dev->dev_private;
@@ -751,14 +796,18 @@ intel_dp_dpms(struct drm_encoder *encoder, int mode)
         if (mode != DRM_MODE_DPMS_ON) {
                 if (dp_reg & DP_PORT_EN) {
                         intel_dp_link_down(intel_encoder, dp_priv->DP);
-                        if (IS_eDP(intel_encoder))
+                        if (IS_eDP(intel_encoder)) {
                                 ironlake_edp_backlight_off(dev);
+                                ironlake_edp_backlight_off(dev);
+                        }
                 }
         } else {
                 if (!(dp_reg & DP_PORT_EN)) {
                         intel_dp_link_train(intel_encoder, dp_priv->DP, dp_priv->link_configuration);
-                        if (IS_eDP(intel_encoder))
+                        if (IS_eDP(intel_encoder)) {
+                                ironlake_edp_panel_on(dev);
                                 ironlake_edp_backlight_on(dev);
+                        }
                 }
         }
         dp_priv->dpms_mode = mode;