drm/omap: protect omap_crtc's event with event_lock spinlock

The vblank_cb callback and the page_flip ioctl can occur together in different
CPU contexts. vblank_cb uses takes tje drm device's event_lock spinlock when
sending the vblank event and updating omap_crtc->event and omap_crtc->od_fb.

Use the same spinlock in page_flip, to make sure the above omap_crtc parameters
are configured sequentially.

Signed-off-by: Archit Taneja <archit@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
This commit is contained in:
Archit Taneja 2014-04-11 12:53:35 +05:30 committed by Tomi Valkeinen
parent bc905aced3
commit 38e5597a03

View File

@ -350,11 +350,15 @@ static int omap_crtc_page_flip_locked(struct drm_crtc *crtc,
struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
struct drm_plane *primary = crtc->primary;
struct drm_gem_object *bo;
unsigned long flags;
DBG("%d -> %d (event=%p)", primary->fb ? primary->fb->base.id : -1,
fb->base.id, event);
spin_lock_irqsave(&dev->event_lock, flags);
if (omap_crtc->old_fb) {
spin_unlock_irqrestore(&dev->event_lock, flags);
dev_err(dev->dev, "already a pending flip\n");
return -EINVAL;
}
@ -362,6 +366,8 @@ static int omap_crtc_page_flip_locked(struct drm_crtc *crtc,
omap_crtc->event = event;
omap_crtc->old_fb = primary->fb = fb;
spin_unlock_irqrestore(&dev->event_lock, flags);
/*
* Hold a reference temporarily until the crtc is updated
* and takes the reference to the bo. This avoids it