From 38e5597a03d2d1499a785230031c4f48e1d9c6b7 Mon Sep 17 00:00:00 2001
From: Archit Taneja <archit@ti.com>
Date: Fri, 11 Apr 2014 12:53:35 +0530
Subject: [PATCH] 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>
---
drivers/gpu/drm/omapdrm/omap_crtc.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/omapdrm/omap_crtc.c b/drivers/gpu/drm/omapdrm/omap_crtc.c
index 00798247190b..e3c47a8005ff 100644
--- a/drivers/gpu/drm/omapdrm/omap_crtc.c
+++ b/drivers/gpu/drm/omapdrm/omap_crtc.c
@@ -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
--
2.30.9