drm/i915: Fix WARN_ON() on UP machines

WARN_ON(!spin_is_locked()) is not a good idea on a UP system w/o
spinlock debugging. Use WARN_ON_SMP() instead.

This check has been added in

commit 8ba2d18520ce380cf572e9902d9b3b91ece6c2c0
Author: Jani Nikula <jani.nikula@intel.com>
Date:   Fri Apr 12 15:18:37 2013 +0300

    drm/i915: protect backlight registers and data with a spinlock

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 56f17b2..80bea1d 100644 (file)
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -332,7 +332,7 @@ static u32 i915_read_blc_pwm_ctl(struct drm_device *dev)
        struct drm_i915_private *dev_priv = dev->dev_private;
        u32 val;
 
-       WARN_ON(!spin_is_locked(&dev_priv->backlight.lock));
+       WARN_ON_SMP(!spin_is_locked(&dev_priv->backlight.lock));
 
        /* Restore the CTL value if it lost, e.g. GPU reset */