drm/i915: Leave LVDS registers unlocked

There's no reason to relock them; it just makes operations more
complex. This fixes DPMS where the panel registers were locked making
the disable not work.

Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>

diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 63188285d7f9b9904e23ee7aa5dc8a3984a9b451..8b521a289b29113f23accf3eed0891be65bfa19b 100644 (file)
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -400,53 +400,21 @@ out:
 
 static void intel_lvds_prepare(struct drm_encoder *encoder)
 {
-       struct drm_device *dev = encoder->dev;
-       struct drm_i915_private *dev_priv = dev->dev_private;
        struct intel_lvds *intel_lvds = to_intel_lvds(encoder);
 
-       /* We try to do the minimum that is necessary in order to unlock
-        * the registers for mode setting.
-        *
-        * On Ironlake, this is quite simple as we just set the unlock key
-        * and ignore all subtleties. (This may cause some issues...)
-        *
+       /*
         * Prior to Ironlake, we must disable the pipe if we want to adjust
         * the panel fitter. However at all other times we can just reset
         * the registers regardless.
         */
-
-       if (HAS_PCH_SPLIT(dev)) {
-               I915_WRITE(PCH_PP_CONTROL,
-                          I915_READ(PCH_PP_CONTROL) | PANEL_UNLOCK_REGS);
-       } else if (intel_lvds->pfit_dirty) {
-               I915_WRITE(PP_CONTROL,
-                          (I915_READ(PP_CONTROL) | PANEL_UNLOCK_REGS)
-                          & ~POWER_TARGET_ON);
-       } else {
-               I915_WRITE(PP_CONTROL,
-                          I915_READ(PP_CONTROL) | PANEL_UNLOCK_REGS);
-       }
+       if (!HAS_PCH_SPLIT(encoder->dev) && intel_lvds->pfit_dirty)
+               intel_lvds_disable(intel_lvds);
 }
 
 static void intel_lvds_commit(struct drm_encoder *encoder)
 {
-       struct drm_device *dev = encoder->dev;
-       struct drm_i915_private *dev_priv = dev->dev_private;
        struct intel_lvds *intel_lvds = to_intel_lvds(encoder);
 
-       /* Undo any unlocking done in prepare to prevent accidental
-        * adjustment of the registers.
-        */
-       if (HAS_PCH_SPLIT(dev)) {
-               u32 val = I915_READ(PCH_PP_CONTROL);
-               if ((val & PANEL_UNLOCK_REGS) == PANEL_UNLOCK_REGS)
-                       I915_WRITE(PCH_PP_CONTROL, val & 0x3);
-       } else {
-               u32 val = I915_READ(PP_CONTROL);
-               if ((val & PANEL_UNLOCK_REGS) == PANEL_UNLOCK_REGS)
-                       I915_WRITE(PP_CONTROL, val & 0x3);
-       }
-
        /* Always do a full power on as we do not know what state
         * we were left in.
         */
@@ -1042,6 +1010,19 @@ out:
                pwm = I915_READ(BLC_PWM_PCH_CTL1);
                pwm |= PWM_PCH_ENABLE;
                I915_WRITE(BLC_PWM_PCH_CTL1, pwm);
+               /*
+                * Unlock registers and just
+                * leave them unlocked
+                */
+               I915_WRITE(PCH_PP_CONTROL,
+                          I915_READ(PCH_PP_CONTROL) | PANEL_UNLOCK_REGS);
+       } else {
+               /*
+                * Unlock registers and just
+                * leave them unlocked
+                */
+               I915_WRITE(PP_CONTROL,
+                          I915_READ(PP_CONTROL) | PANEL_UNLOCK_REGS);
        }
        dev_priv->lid_notifier.notifier_call = intel_lid_notify;
        if (acpi_lid_notifier_register(&dev_priv->lid_notifier)) {