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authorJesse Barnes <jbarnes@virtuousgeek.org>2009-01-08 10:42:15 -0800
committerDave Airlie <airlied@linux.ie>2009-01-11 08:59:48 +1000
commit71e0ffa599f54058d9b8724b4b14d0486751681d (patch)
tree93995ec627de4ef0e211965ed83fab58804f8770 /drivers/gpu/drm/i915/i915_irq.c
parent3d14bdad40315b54470cb7812293d14c8af2bf7d (diff)
downloadlinux-71e0ffa599f54058d9b8724b4b14d0486751681d.tar.bz2
drm/i915: don't enable vblanks on disabled pipes
In some cases userland may be confused and try to wait on vblank events from pipes that aren't actually enabled. We shouldn't allow this, so return -EINVAL if the pipe isn't on. Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Eric Anholt <eric@anholt.net> Signed-off-by: Dave Airlie <airlied@linux.ie>
Diffstat (limited to 'drivers/gpu/drm/i915/i915_irq.c')
-rw-r--r--drivers/gpu/drm/i915/i915_irq.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 0cadafbef411..6290219de6c8 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -411,6 +411,12 @@ int i915_enable_vblank(struct drm_device *dev, int pipe)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
unsigned long irqflags;
+ int pipeconf_reg = (pipe == 0) ? PIPEACONF : PIPEBCONF;
+ u32 pipeconf;
+
+ pipeconf = I915_READ(pipeconf_reg);
+ if (!(pipeconf & PIPEACONF_ENABLE))
+ return -EINVAL;
spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
if (IS_I965G(dev))