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authorLen Brown <len.brown@intel.com>2008-10-22 23:57:26 -0400
committerLen Brown <len.brown@intel.com>2008-10-23 00:11:07 -0400
commit057316cc6a5b521b332a1d7ccc871cd60c904c74 (patch)
tree4333e608da237c73ff69b10878025cca96dcb4c8 /drivers/gpu/drm/drm_irq.c
parent3e2dab9a1c2deb03c311eb3f83466009147ed4d3 (diff)
parent2515ddc6db8eb49a79f0fe5e67ff09ac7c81eab4 (diff)
Merge branch 'linus' into test
Conflicts: MAINTAINERS arch/x86/kernel/acpi/boot.c arch/x86/kernel/acpi/sleep.c drivers/acpi/Kconfig drivers/pnp/Makefile drivers/pnp/quirks.c Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/gpu/drm/drm_irq.c')
-rw-r--r--drivers/gpu/drm/drm_irq.c464
1 files changed, 387 insertions, 77 deletions
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 53f0e5af1cc..4091b9e291f 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -63,7 +63,7 @@ int drm_irq_by_busid(struct drm_device *dev, void *data,
p->devnum != PCI_SLOT(dev->pdev->devfn) || p->funcnum != PCI_FUNC(dev->pdev->devfn))
return -EINVAL;
- p->irq = dev->irq;
+ p->irq = dev->pdev->irq;
DRM_DEBUG("%d:%d:%d => IRQ %d\n", p->busnum, p->devnum, p->funcnum,
p->irq);
@@ -71,25 +71,137 @@ int drm_irq_by_busid(struct drm_device *dev, void *data,
return 0;
}
+static void vblank_disable_fn(unsigned long arg)
+{
+ struct drm_device *dev = (struct drm_device *)arg;
+ unsigned long irqflags;
+ int i;
+
+ if (!dev->vblank_disable_allowed)
+ return;
+
+ for (i = 0; i < dev->num_crtcs; i++) {
+ spin_lock_irqsave(&dev->vbl_lock, irqflags);
+ if (atomic_read(&dev->vblank_refcount[i]) == 0 &&
+ dev->vblank_enabled[i]) {
+ DRM_DEBUG("disabling vblank on crtc %d\n", i);
+ dev->last_vblank[i] =
+ dev->driver->get_vblank_counter(dev, i);
+ dev->driver->disable_vblank(dev, i);
+ dev->vblank_enabled[i] = 0;
+ }
+ spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
+ }
+}
+
+static void drm_vblank_cleanup(struct drm_device *dev)
+{
+ /* Bail if the driver didn't call drm_vblank_init() */
+ if (dev->num_crtcs == 0)
+ return;
+
+ del_timer(&dev->vblank_disable_timer);
+
+ vblank_disable_fn((unsigned long)dev);
+
+ drm_free(dev->vbl_queue, sizeof(*dev->vbl_queue) * dev->num_crtcs,
+ DRM_MEM_DRIVER);
+ drm_free(dev->vbl_sigs, sizeof(*dev->vbl_sigs) * dev->num_crtcs,
+ DRM_MEM_DRIVER);
+ drm_free(dev->_vblank_count, sizeof(*dev->_vblank_count) *
+ dev->num_crtcs, DRM_MEM_DRIVER);
+ drm_free(dev->vblank_refcount, sizeof(*dev->vblank_refcount) *
+ dev->num_crtcs, DRM_MEM_DRIVER);
+ drm_free(dev->vblank_enabled, sizeof(*dev->vblank_enabled) *
+ dev->num_crtcs, DRM_MEM_DRIVER);
+ drm_free(dev->last_vblank, sizeof(*dev->last_vblank) * dev->num_crtcs,
+ DRM_MEM_DRIVER);
+ drm_free(dev->vblank_inmodeset, sizeof(*dev->vblank_inmodeset) *
+ dev->num_crtcs, DRM_MEM_DRIVER);
+
+ dev->num_crtcs = 0;
+}
+
+int drm_vblank_init(struct drm_device *dev, int num_crtcs)
+{
+ int i, ret = -ENOMEM;
+
+ setup_timer(&dev->vblank_disable_timer, vblank_disable_fn,
+ (unsigned long)dev);
+ spin_lock_init(&dev->vbl_lock);
+ atomic_set(&dev->vbl_signal_pending, 0);
+ dev->num_crtcs = num_crtcs;
+
+ dev->vbl_queue = drm_alloc(sizeof(wait_queue_head_t) * num_crtcs,
+ DRM_MEM_DRIVER);
+ if (!dev->vbl_queue)
+ goto err;
+
+ dev->vbl_sigs = drm_alloc(sizeof(struct list_head) * num_crtcs,
+ DRM_MEM_DRIVER);
+ if (!dev->vbl_sigs)
+ goto err;
+
+ dev->_vblank_count = drm_alloc(sizeof(atomic_t) * num_crtcs,
+ DRM_MEM_DRIVER);
+ if (!dev->_vblank_count)
+ goto err;
+
+ dev->vblank_refcount = drm_alloc(sizeof(atomic_t) * num_crtcs,
+ DRM_MEM_DRIVER);
+ if (!dev->vblank_refcount)
+ goto err;
+
+ dev->vblank_enabled = drm_calloc(num_crtcs, sizeof(int),
+ DRM_MEM_DRIVER);
+ if (!dev->vblank_enabled)
+ goto err;
+
+ dev->last_vblank = drm_calloc(num_crtcs, sizeof(u32), DRM_MEM_DRIVER);
+ if (!dev->last_vblank)
+ goto err;
+
+ dev->vblank_inmodeset = drm_calloc(num_crtcs, sizeof(int),
+ DRM_MEM_DRIVER);
+ if (!dev->vblank_inmodeset)
+ goto err;
+
+ /* Zero per-crtc vblank stuff */
+ for (i = 0; i < num_crtcs; i++) {
+ init_waitqueue_head(&dev->vbl_queue[i]);
+ INIT_LIST_HEAD(&dev->vbl_sigs[i]);
+ atomic_set(&dev->_vblank_count[i], 0);
+ atomic_set(&dev->vblank_refcount[i], 0);
+ }
+
+ dev->vblank_disable_allowed = 0;
+
+ return 0;
+
+err:
+ drm_vblank_cleanup(dev);
+ return ret;
+}
+EXPORT_SYMBOL(drm_vblank_init);
+
/**
* Install IRQ handler.
*
* \param dev DRM device.
- * \param irq IRQ number.
*
- * Initializes the IRQ related data, and setups drm_device::vbl_queue. Installs the handler, calling the driver
+ * Initializes the IRQ related data. Installs the handler, calling the driver
* \c drm_driver_irq_preinstall() and \c drm_driver_irq_postinstall() functions
* before and after the installation.
*/
-static int drm_irq_install(struct drm_device * dev)
+int drm_irq_install(struct drm_device *dev)
{
- int ret;
+ int ret = 0;
unsigned long sh_flags = 0;
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return -EINVAL;
- if (dev->irq == 0)
+ if (dev->pdev->irq == 0)
return -EINVAL;
mutex_lock(&dev->struct_mutex);
@@ -107,18 +219,7 @@ static int drm_irq_install(struct drm_device * dev)
dev->irq_enabled = 1;
mutex_unlock(&dev->struct_mutex);
- DRM_DEBUG("irq=%d\n", dev->irq);
-
- if (drm_core_check_feature(dev, DRIVER_IRQ_VBL)) {
- init_waitqueue_head(&dev->vbl_queue);
-
- spin_lock_init(&dev->vbl_lock);
-
- INIT_LIST_HEAD(&dev->vbl_sigs);
- INIT_LIST_HEAD(&dev->vbl_sigs2);
-
- dev->vbl_pending = 0;
- }
+ DRM_DEBUG("irq=%d\n", dev->pdev->irq);
/* Before installing handler */
dev->driver->irq_preinstall(dev);
@@ -127,8 +228,9 @@ static int drm_irq_install(struct drm_device * dev)
if (drm_core_check_feature(dev, DRIVER_IRQ_SHARED))
sh_flags = IRQF_SHARED;
- ret = request_irq(dev->irq, dev->driver->irq_handler,
+ ret = request_irq(drm_dev_to_irq(dev), dev->driver->irq_handler,
sh_flags, dev->devname, dev);
+
if (ret < 0) {
mutex_lock(&dev->struct_mutex);
dev->irq_enabled = 0;
@@ -137,10 +239,16 @@ static int drm_irq_install(struct drm_device * dev)
}
/* After installing handler */
- dev->driver->irq_postinstall(dev);
+ ret = dev->driver->irq_postinstall(dev);
+ if (ret < 0) {
+ mutex_lock(&dev->struct_mutex);
+ dev->irq_enabled = 0;
+ mutex_unlock(&dev->struct_mutex);
+ }
- return 0;
+ return ret;
}
+EXPORT_SYMBOL(drm_irq_install);
/**
* Uninstall the IRQ handler.
@@ -164,17 +272,18 @@ int drm_irq_uninstall(struct drm_device * dev)
if (!irq_enabled)
return -EINVAL;
- DRM_DEBUG("irq=%d\n", dev->irq);
+ DRM_DEBUG("irq=%d\n", dev->pdev->irq);
dev->driver->irq_uninstall(dev);
- free_irq(dev->irq, dev);
+ free_irq(dev->pdev->irq, dev);
+
+ drm_vblank_cleanup(dev);
dev->locked_tasklet_func = NULL;
return 0;
}
-
EXPORT_SYMBOL(drm_irq_uninstall);
/**
@@ -201,7 +310,7 @@ int drm_control(struct drm_device *dev, void *data,
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return 0;
if (dev->if_version < DRM_IF_VERSION(1, 2) &&
- ctl->irq != dev->irq)
+ ctl->irq != dev->pdev->irq)
return -EINVAL;
return drm_irq_install(dev);
case DRM_UNINST_HANDLER:
@@ -214,6 +323,174 @@ int drm_control(struct drm_device *dev, void *data,
}
/**
+ * drm_vblank_count - retrieve "cooked" vblank counter value
+ * @dev: DRM device
+ * @crtc: which counter to retrieve
+ *
+ * Fetches the "cooked" vblank count value that represents the number of
+ * vblank events since the system was booted, including lost events due to
+ * modesetting activity.
+ */
+u32 drm_vblank_count(struct drm_device *dev, int crtc)
+{
+ return atomic_read(&dev->_vblank_count[crtc]);
+}
+EXPORT_SYMBOL(drm_vblank_count);
+
+/**
+ * drm_update_vblank_count - update the master vblank counter
+ * @dev: DRM device
+ * @crtc: counter to update
+ *
+ * Call back into the driver to update the appropriate vblank counter
+ * (specified by @crtc). Deal with wraparound, if it occurred, and
+ * update the last read value so we can deal with wraparound on the next
+ * call if necessary.
+ *
+ * Only necessary when going from off->on, to account for frames we
+ * didn't get an interrupt for.
+ *
+ * Note: caller must hold dev->vbl_lock since this reads & writes
+ * device vblank fields.
+ */
+static void drm_update_vblank_count(struct drm_device *dev, int crtc)
+{
+ u32 cur_vblank, diff;
+
+ /*
+ * Interrupts were disabled prior to this call, so deal with counter
+ * wrap if needed.
+ * NOTE! It's possible we lost a full dev->max_vblank_count events
+ * here if the register is small or we had vblank interrupts off for
+ * a long time.
+ */
+ cur_vblank = dev->driver->get_vblank_counter(dev, crtc);
+ diff = cur_vblank - dev->last_vblank[crtc];
+ if (cur_vblank < dev->last_vblank[crtc]) {
+ diff += dev->max_vblank_count;
+
+ DRM_DEBUG("last_vblank[%d]=0x%x, cur_vblank=0x%x => diff=0x%x\n",
+ crtc, dev->last_vblank[crtc], cur_vblank, diff);
+ }
+
+ DRM_DEBUG("enabling vblank interrupts on crtc %d, missed %d\n",
+ crtc, diff);
+
+ atomic_add(diff, &dev->_vblank_count[crtc]);
+}
+
+/**
+ * drm_vblank_get - get a reference count on vblank events
+ * @dev: DRM device
+ * @crtc: which CRTC to own
+ *
+ * Acquire a reference count on vblank events to avoid having them disabled
+ * while in use.
+ *
+ * RETURNS
+ * Zero on success, nonzero on failure.
+ */
+int drm_vblank_get(struct drm_device *dev, int crtc)
+{
+ unsigned long irqflags;
+ int ret = 0;
+
+ spin_lock_irqsave(&dev->vbl_lock, irqflags);
+ /* Going from 0->1 means we have to enable interrupts again */
+ if (atomic_add_return(1, &dev->vblank_refcount[crtc]) == 1 &&
+ !dev->vblank_enabled[crtc]) {
+ ret = dev->driver->enable_vblank(dev, crtc);
+ DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", crtc, ret);
+ if (ret)
+ atomic_dec(&dev->vblank_refcount[crtc]);
+ else {
+ dev->vblank_enabled[crtc] = 1;
+ drm_update_vblank_count(dev, crtc);
+ }
+ }
+ spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
+
+ return ret;
+}
+EXPORT_SYMBOL(drm_vblank_get);
+
+/**
+ * drm_vblank_put - give up ownership of vblank events
+ * @dev: DRM device
+ * @crtc: which counter to give up
+ *
+ * Release ownership of a given vblank counter, turning off interrupts
+ * if possible.
+ */
+void drm_vblank_put(struct drm_device *dev, int crtc)
+{
+ /* Last user schedules interrupt disable */
+ if (atomic_dec_and_test(&dev->vblank_refcount[crtc]))
+ mod_timer(&dev->vblank_disable_timer, jiffies + 5*DRM_HZ);
+}
+EXPORT_SYMBOL(drm_vblank_put);
+
+/**
+ * drm_modeset_ctl - handle vblank event counter changes across mode switch
+ * @DRM_IOCTL_ARGS: standard ioctl arguments
+ *
+ * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET
+ * ioctls around modesetting so that any lost vblank events are accounted for.
+ *
+ * Generally the counter will reset across mode sets. If interrupts are
+ * enabled around this call, we don't have to do anything since the counter
+ * will have already been incremented.
+ */
+int drm_modeset_ctl(struct drm_device *dev, void *data,
+ struct drm_file *file_priv)
+{
+ struct drm_modeset_ctl *modeset = data;
+ unsigned long irqflags;
+ int crtc, ret = 0;
+
+ /* If drm_vblank_init() hasn't been called yet, just no-op */
+ if (!dev->num_crtcs)
+ goto out;
+
+ crtc = modeset->crtc;
+ if (crtc >= dev->num_crtcs) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /*
+ * To avoid all the problems that might happen if interrupts
+ * were enabled/disabled around or between these calls, we just
+ * have the kernel take a reference on the CRTC (just once though
+ * to avoid corrupting the count if multiple, mismatch calls occur),
+ * so that interrupts remain enabled in the interim.
+ */
+ switch (modeset->cmd) {
+ case _DRM_PRE_MODESET:
+ if (!dev->vblank_inmodeset[crtc]) {
+ dev->vblank_inmodeset[crtc] = 1;
+ drm_vblank_get(dev, crtc);
+ }
+ break;
+ case _DRM_POST_MODESET:
+ if (dev->vblank_inmodeset[crtc]) {
+ spin_lock_irqsave(&dev->vbl_lock, irqflags);
+ dev->vblank_disable_allowed = 1;
+ dev->vblank_inmodeset[crtc] = 0;
+ spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
+ drm_vblank_put(dev, crtc);
+ }
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+out:
+ return ret;
+}
+
+/**
* Wait for VBLANK.
*
* \param inode device inode.
@@ -232,14 +509,14 @@ int drm_control(struct drm_device *dev, void *data,
*
* If a signal is not requested, then calls vblank_wait().
*/
-int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_priv)
+int drm_wait_vblank(struct drm_device *dev, void *data,
+ struct drm_file *file_priv)
{
union drm_wait_vblank *vblwait = data;
- struct timeval now;
int ret = 0;
- unsigned int flags, seq;
+ unsigned int flags, seq, crtc;
- if ((!dev->irq) || (!dev->irq_enabled))
+ if ((!dev->pdev->irq) || (!dev->irq_enabled))
return -EINVAL;
if (vblwait->request.type &
@@ -251,13 +528,17 @@ int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_pr
}
flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
+ crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
- if (!drm_core_check_feature(dev, (flags & _DRM_VBLANK_SECONDARY) ?
- DRIVER_IRQ_VBL2 : DRIVER_IRQ_VBL))
+ if (crtc >= dev->num_crtcs)
return -EINVAL;
- seq = atomic_read((flags & _DRM_VBLANK_SECONDARY) ? &dev->vbl_received2
- : &dev->vbl_received);
+ ret = drm_vblank_get(dev, crtc);
+ if (ret) {
+ DRM_ERROR("failed to acquire vblank counter, %d\n", ret);
+ return ret;
+ }
+ seq = drm_vblank_count(dev, crtc);
switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
case _DRM_VBLANK_RELATIVE:
@@ -266,7 +547,8 @@ int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_pr
case _DRM_VBLANK_ABSOLUTE:
break;
default:
- return -EINVAL;
+ ret = -EINVAL;
+ goto done;
}
if ((flags & _DRM_VBLANK_NEXTONMISS) &&
@@ -276,8 +558,7 @@ int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_pr
if (flags & _DRM_VBLANK_SIGNAL) {
unsigned long irqflags;
- struct list_head *vbl_sigs = (flags & _DRM_VBLANK_SECONDARY)
- ? &dev->vbl_sigs2 : &dev->vbl_sigs;
+ struct list_head *vbl_sigs = &dev->vbl_sigs[crtc];
struct drm_vbl_sig *vbl_sig;
spin_lock_irqsave(&dev->vbl_lock, irqflags);
@@ -298,22 +579,29 @@ int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_pr
}
}
- if (dev->vbl_pending >= 100) {
+ if (atomic_read(&dev->vbl_signal_pending) >= 100) {
spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
- return -EBUSY;
+ ret = -EBUSY;
+ goto done;
}
- dev->vbl_pending++;
-
spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
- if (!
- (vbl_sig =
- drm_alloc(sizeof(struct drm_vbl_sig), DRM_MEM_DRIVER))) {
- return -ENOMEM;
+ vbl_sig = drm_calloc(1, sizeof(struct drm_vbl_sig),
+ DRM_MEM_DRIVER);
+ if (!vbl_sig) {
+ ret = -ENOMEM;
+ goto done;
+ }
+
+ ret = drm_vblank_get(dev, crtc);
+ if (ret) {
+ drm_free(vbl_sig, sizeof(struct drm_vbl_sig),
+ DRM_MEM_DRIVER);
+ return ret;
}
- memset((void *)vbl_sig, 0, sizeof(*vbl_sig));
+ atomic_inc(&dev->vbl_signal_pending);
vbl_sig->sequence = vblwait->request.sequence;
vbl_sig->info.si_signo = vblwait->request.signal;
@@ -327,20 +615,29 @@ int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_pr
vblwait->reply.sequence = seq;
} else {
- if (flags & _DRM_VBLANK_SECONDARY) {
- if (dev->driver->vblank_wait2)
- ret = dev->driver->vblank_wait2(dev, &vblwait->request.sequence);
- } else if (dev->driver->vblank_wait)
- ret =
- dev->driver->vblank_wait(dev,
- &vblwait->request.sequence);
-
- do_gettimeofday(&now);
- vblwait->reply.tval_sec = now.tv_sec;
- vblwait->reply.tval_usec = now.tv_usec;
+ DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
+ vblwait->request.sequence, crtc);
+ DRM_WAIT_ON(ret, dev->vbl_queue[crtc], 3 * DRM_HZ,
+ ((drm_vblank_count(dev, crtc)
+ - vblwait->request.sequence) <= (1 << 23)));
+
+ if (ret != -EINTR) {
+ struct timeval now;
+
+ do_gettimeofday(&now);
+
+ vblwait->reply.tval_sec = now.tv_sec;
+ vblwait->reply.tval_usec = now.tv_usec;
+ vblwait->reply.sequence = drm_vblank_count(dev, crtc);
+ DRM_DEBUG("returning %d to client\n",
+ vblwait->reply.sequence);
+ } else {
+ DRM_DEBUG("vblank wait interrupted by signal\n");
+ }
}
- done:
+done:
+ drm_vblank_put(dev, crtc);
return ret;
}
@@ -348,44 +645,57 @@ int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_pr
* Send the VBLANK signals.
*
* \param dev DRM device.
+ * \param crtc CRTC where the vblank event occurred
*
* Sends a signal for each task in drm_device::vbl_sigs and empties the list.
*
* If a signal is not requested, then calls vblank_wait().
*/
-void drm_vbl_send_signals(struct drm_device * dev)
+static void drm_vbl_send_signals(struct drm_device *dev, int crtc)
{
+ struct drm_vbl_sig *vbl_sig, *tmp;
+ struct list_head *vbl_sigs;
+ unsigned int vbl_seq;
unsigned long flags;
- int i;
spin_lock_irqsave(&dev->vbl_lock, flags);
- for (i = 0; i < 2; i++) {
- struct drm_vbl_sig *vbl_sig, *tmp;
- struct list_head *vbl_sigs = i ? &dev->vbl_sigs2 : &dev->vbl_sigs;
- unsigned int vbl_seq = atomic_read(i ? &dev->vbl_received2 :
- &dev->vbl_received);
+ vbl_sigs = &dev->vbl_sigs[crtc];
+ vbl_seq = drm_vblank_count(dev, crtc);
- list_for_each_entry_safe(vbl_sig, tmp, vbl_sigs, head) {
- if ((vbl_seq - vbl_sig->sequence) <= (1 << 23)) {
- vbl_sig->info.si_code = vbl_seq;
- send_sig_info(vbl_sig->info.si_signo,
- &vbl_sig->info, vbl_sig->task);
+ list_for_each_entry_safe(vbl_sig, tmp, vbl_sigs, head) {
+ if ((vbl_seq - vbl_sig->sequence) <= (1 << 23)) {
+ vbl_sig->info.si_code = vbl_seq;
+ send_sig_info(vbl_sig->info.si_signo,
+ &vbl_sig->info, vbl_sig->task);
- list_del(&vbl_sig->head);
-
- drm_free(vbl_sig, sizeof(*vbl_sig),
- DRM_MEM_DRIVER);
+ list_del(&vbl_sig->head);
- dev->vbl_pending--;
- }
- }
+ drm_free(vbl_sig, sizeof(*vbl_sig),
+ DRM_MEM_DRIVER);
+ atomic_dec(&dev->vbl_signal_pending);
+ drm_vblank_put(dev, crtc);
+ }
}
spin_unlock_irqrestore(&dev->vbl_lock, flags);
}
-EXPORT_SYMBOL(drm_vbl_send_signals);
+/**
+ * drm_handle_vblank - handle a vblank event
+ * @dev: DRM device
+ * @crtc: where this event occurred
+ *
+ * Drivers should call this routine in their vblank interrupt handlers to
+ * update the vblank counter and send any signals that may be pending.
+ */
+void drm_handle_vblank(struct drm_device *dev, int crtc)
+{
+ atomic_inc(&dev->_vblank_count[crtc]);
+ DRM_WAKEUP(&dev->vbl_queue[crtc]);
+ drm_vbl_send_signals(dev, crtc);
+}
+EXPORT_SYMBOL(drm_handle_vblank);
/**
* Tasklet wrapper function.