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@intel.com Cc: Gaurav K Singh gaurav.k.singh@intel.com Cc: Michel Dänzer michel.daenzer@amd.com Cc: Ville Syrjälä ville.syrjala@linux.intel.com Signed-off-by: Daniel Vetter daniel.vetter@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);