We should never nest these since in theory kms drivers should know
when a pipe is on/off and call the corresponding enable/disable
functions for the vblank helper code only once. But for historical
reasons (the shared-with-ums version of this code in modeset_pre/post
needed to be able to cope with silly userspace that lost track of
things) we still have this bit of "robustness" around.
Enforce this with a WARN_ON, preparing to eventually rip out this
special handling.
Cc: Yogesh Mohan Marimuthu <yogesh.mohan.marimuthu at intel.com>
Cc: Gaurav K Singh <gaurav.k.singh at intel.com>
Cc: Michel Dänzer <michel.daenzer at amd.com>
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
---
drivers/gpu/drm/drm_irq.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index f9cc68fbd2a3..3819465abe22 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -1219,6 +1219,8 @@ void drm_vblank_off(struct drm_device *dev, int crtc)
vblank_disable_and_save(dev, crtc);
wake_up(&vblank->queue);
+ WARN_ON(vblank->inmodeset);
+
/*
* Prevent subsequent drm_vblank_get() from re-enabling
* the vblank interrupt by bumping the refcount.
@@ -1318,6 +1320,8 @@ void drm_vblank_on(struct drm_device *dev, int crtc)
return;
spin_lock_irqsave(&dev->vbl_lock, irqflags);
+ WARN_ON(!vblank->inmodeset);
+
/* Drop our private "prevent drm_vblank_get" refcount */
if (vblank->inmodeset) {
atomic_dec(&vblank->refcount);
--
2.1.4
