4 files changed, 194 insertions, 2 deletions

diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c
index 251bc0e3b5ec..8ac7fbf6b2b7 100644
--- a/drivers/gpu/drm/drm_fops.c
+++ b/drivers/gpu/drm/drm_fops.c
@@ -257,6 +257,9 @@ static int drm_open_helper(struct inode *inode, struct file *filp,
 
 	INIT_LIST_HEAD(&priv->lhead);
 	INIT_LIST_HEAD(&priv->fbs);
+	INIT_LIST_HEAD(&priv->event_list);
+	init_waitqueue_head(&priv->event_wait);
+	priv->event_space = 4096; /* set aside 4k for event buffer */
 
 	if (dev->driver->driver_features & DRIVER_GEM)
 		drm_gem_open(dev, priv);
@@ -413,6 +416,30 @@ static void drm_master_release(struct drm_device *dev, struct file *filp)
 	}
 }
 
+static void drm_events_release(struct drm_file *file_priv)
+{
+	struct drm_device *dev = file_priv->minor->dev;
+	struct drm_pending_event *e, *et;
+	struct drm_pending_vblank_event *v, *vt;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->event_lock, flags);
+
+	/* Remove pending flips */
+	list_for_each_entry_safe(v, vt, &dev->vblank_event_list, base.link)
+		if (v->base.file_priv == file_priv) {
+			list_del(&v->base.link);
+			drm_vblank_put(dev, v->pipe);
+			v->base.destroy(&v->base);
+		}
+
+	/* Remove unconsumed events */
+	list_for_each_entry_safe(e, et, &file_priv->event_list, link)
+		e->destroy(e);
+
+	spin_unlock_irqrestore(&dev->event_lock, flags);
+}
+
 /**
  * Release file.
  *
@@ -451,6 +478,8 @@ int drm_release(struct inode *inode, struct file *filp)
 	if (file_priv->minor->master)
 		drm_master_release(dev, filp);
 
+	drm_events_release(file_priv);
+
 	if (dev->driver->driver_features & DRIVER_GEM)
 		drm_gem_release(dev, file_priv);
 
@@ -544,9 +573,74 @@ int drm_release(struct inode *inode, struct file *filp)
 }
 EXPORT_SYMBOL(drm_release);
 
-/** No-op. */
+static bool
+drm_dequeue_event(struct drm_file *file_priv,
+		  size_t total, size_t max, struct drm_pending_event **out)
+{
+	struct drm_device *dev = file_priv->minor->dev;
+	struct drm_pending_event *e;
+	unsigned long flags;
+	bool ret = false;
+
+	spin_lock_irqsave(&dev->event_lock, flags);
+
+	*out = NULL;
+	if (list_empty(&file_priv->event_list))
+		goto out;
+	e = list_first_entry(&file_priv->event_list,
+			     struct drm_pending_event, link);
+	if (e->event->length + total > max)
+		goto out;
+
+	file_priv->event_space += e->event->length;
+	list_del(&e->link);
+	*out = e;
+	ret = true;
+
+out:
+	spin_unlock_irqrestore(&dev->event_lock, flags);
+	return ret;
+}
+
+ssize_t drm_read(struct file *filp, char __user *buffer,
+		 size_t count, loff_t *offset)
+{
+	struct drm_file *file_priv = filp->private_data;
+	struct drm_pending_event *e;
+	size_t total;
+	ssize_t ret;
+
+	ret = wait_event_interruptible(file_priv->event_wait,
+				       !list_empty(&file_priv->event_list));
+	if (ret < 0)
+		return ret;
+
+	total = 0;
+	while (drm_dequeue_event(file_priv, total, count, &e)) {
+		if (copy_to_user(buffer + total,
+				 e->event, e->event->length)) {
+			total = -EFAULT;
+			break;
+		}
+
+		total += e->event->length;
+		e->destroy(e);
+	}
+
+	return total;
+}
+EXPORT_SYMBOL(drm_read);
+
 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
 {
-	return 0;
+	struct drm_file *file_priv = filp->private_data;
+	unsigned int mask = 0;
+
+	poll_wait(filp, &file_priv->event_wait, wait);
+
+	if (!list_empty(&file_priv->event_list))
+		mask |= POLLIN | POLLRDNORM;
+
+	return mask;
 }
 EXPORT_SYMBOL(drm_poll);
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 0a6f0b3bdc78..72754aca7abf 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -550,6 +550,62 @@ out:
 	return ret;
 }
 
+static int drm_queue_vblank_event(struct drm_device *dev, int pipe,
+				  union drm_wait_vblank *vblwait,
+				  struct drm_file *file_priv)
+{
+	struct drm_pending_vblank_event *e;
+	struct timeval now;
+	unsigned long flags;
+	unsigned int seq;
+
+	e = kzalloc(sizeof *e, GFP_KERNEL);
+	if (e == NULL)
+		return -ENOMEM;
+
+	e->pipe = pipe;
+	e->event.base.type = DRM_EVENT_VBLANK;
+	e->event.base.length = sizeof e->event;
+	e->event.user_data = vblwait->request.signal;
+	e->base.event = &e->event.base;
+	e->base.file_priv = file_priv;
+	e->base.destroy = (void (*) (struct drm_pending_event *)) kfree;
+
+	do_gettimeofday(&now);
+	spin_lock_irqsave(&dev->event_lock, flags);
+
+	if (file_priv->event_space < sizeof e->event) {
+		spin_unlock_irqrestore(&dev->event_lock, flags);
+		kfree(e);
+		return -ENOMEM;
+	}
+
+	file_priv->event_space -= sizeof e->event;
+	seq = drm_vblank_count(dev, pipe);
+	if ((vblwait->request.type & _DRM_VBLANK_NEXTONMISS) &&
+	    (seq - vblwait->request.sequence) <= (1 << 23)) {
+		vblwait->request.sequence = seq + 1;
+	}
+
+	DRM_DEBUG("event on vblank count %d, current %d, crtc %d\n",
+		  vblwait->request.sequence, seq, pipe);
+
+	e->event.sequence = vblwait->request.sequence;
+	if ((seq - vblwait->request.sequence) <= (1 << 23)) {
+		e->event.tv_sec = now.tv_sec;
+		e->event.tv_usec = now.tv_usec;
+		drm_vblank_put(dev, e->pipe);
+		list_add_tail(&e->base.link, &e->base.file_priv->event_list);
+		wake_up_interruptible(&e->base.file_priv->event_wait);
+	} else {
+		list_add_tail(&e->base.link, &dev->vblank_event_list);
+	}
+
+	spin_unlock_irqrestore(&dev->event_lock, flags);
+
+	return 0;
+}
+
 /**
  * Wait for VBLANK.
  *
@@ -609,6 +665,9 @@ int drm_wait_vblank(struct drm_device *dev, void *data,
 		goto done;
 	}
 
+	if (flags & _DRM_VBLANK_EVENT)
+		return drm_queue_vblank_event(dev, crtc, vblwait, file_priv);
+
 	if ((flags & _DRM_VBLANK_NEXTONMISS) &&
 	    (seq - vblwait->request.sequence) <= (1<<23)) {
 		vblwait->request.sequence = seq + 1;
@@ -641,6 +700,38 @@ done:
 	return ret;
 }
 
+void drm_handle_vblank_events(struct drm_device *dev, int crtc)
+{
+	struct drm_pending_vblank_event *e, *t;
+	struct timeval now;
+	unsigned long flags;
+	unsigned int seq;
+
+	do_gettimeofday(&now);
+	seq = drm_vblank_count(dev, crtc);
+
+	spin_lock_irqsave(&dev->event_lock, flags);
+
+	list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
+		if (e->pipe != crtc)
+			continue;
+		if ((seq - e->event.sequence) > (1<<23))
+			continue;
+
+		DRM_DEBUG("vblank event on %d, current %d\n",
+			  e->event.sequence, seq);
+
+		e->event.sequence = seq;
+		e->event.tv_sec = now.tv_sec;
+		e->event.tv_usec = now.tv_usec;
+		drm_vblank_put(dev, e->pipe);
+		list_move_tail(&e->base.link, &e->base.file_priv->event_list);
+		wake_up_interruptible(&e->base.file_priv->event_wait);
+	}
+
+	spin_unlock_irqrestore(&dev->event_lock, flags);
+}
+
 /**
  * drm_handle_vblank - handle a vblank event
  * @dev: DRM device
@@ -651,7 +742,11 @@ done:
  */
 void drm_handle_vblank(struct drm_device *dev, int crtc)
 {
+	if (!dev->num_crtcs)
+		return;
+
 	atomic_inc(&dev->_vblank_count[crtc]);
 	DRM_WAKEUP(&dev->vbl_queue[crtc]);
+	drm_handle_vblank_events(dev, crtc);
 }
 EXPORT_SYMBOL(drm_handle_vblank);
diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c
index 55bb8a82d612..adb864dfef3e 100644
--- a/drivers/gpu/drm/drm_stub.c
+++ b/drivers/gpu/drm/drm_stub.c
@@ -220,9 +220,11 @@ static int drm_fill_in_dev(struct drm_device * dev, struct pci_dev *pdev,
 	INIT_LIST_HEAD(&dev->ctxlist);
 	INIT_LIST_HEAD(&dev->vmalist);
 	INIT_LIST_HEAD(&dev->maplist);
+	INIT_LIST_HEAD(&dev->vblank_event_list);
 
 	spin_lock_init(&dev->count_lock);
 	spin_lock_init(&dev->drw_lock);
+	spin_lock_init(&dev->event_lock);
 	init_timer(&dev->timer);
 	mutex_init(&dev->struct_mutex);
 	mutex_init(&dev->ctxlist_mutex);
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 7f436ec075f6..2fa217862058 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -333,6 +333,7 @@ static struct drm_driver driver = {
 		 .mmap = drm_gem_mmap,
 		 .poll = drm_poll,
 		 .fasync = drm_fasync,
+		 .read = drm_read,
 #ifdef CONFIG_COMPAT
 		 .compat_ioctl = i915_compat_ioctl,
 #endif