drm/i915: Unlock panel even when LVDS is disabled

commit b0616c5306b342ceca07044dbc4f917d95c4f825 upstream.

Otherwise we'll have backtraces in assert_panel_unlocked because the
BIOS locks the register. In the reporter's case this regression was
introduced in

commit c31407a3672aaebb4acddf90944a114fa5c8af7b
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Thu Oct 18 21:07:01 2012 +0100

    drm/i915: Add no-lvds quirk for Supermicro X7SPA-H

Reported-by: Alexey Orishko <alexey.orishko@gmail.com>
Cc: Alexey Orishko <alexey.orishko@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Francois Tigeot <ftigeot@wolfpond.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Tested-by: Alexey Orishko <alexey.orishko@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
[bwh: Backported to 3.2: adjust context; comment was duplicated]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index fadd021..4da8182 100644 (file)
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -914,6 +914,18 @@ bool intel_lvds_init(struct drm_device *dev)
        int pipe;
        u8 pin;
 
+       /*
+        * Unlock registers and just leave them unlocked. Do this before
+        * checking quirk lists to avoid bogus WARNINGs.
+        */
+       if (HAS_PCH_SPLIT(dev)) {
+               I915_WRITE(PCH_PP_CONTROL,
+                          I915_READ(PCH_PP_CONTROL) | PANEL_UNLOCK_REGS);
+       } else {
+               I915_WRITE(PP_CONTROL,
+                          I915_READ(PP_CONTROL) | PANEL_UNLOCK_REGS);
+       }
+
        /* Skip init on machines we know falsely report LVDS */
        if (dmi_check_system(intel_no_lvds))
                return false;
@@ -1088,19 +1100,6 @@ 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)) {