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drm/linux-core/drm_irq.c

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/**
* \file drm_irq.c
* IRQ support
*
* \author Rickard E. (Rik) Faith <faith@valinux.com>
* \author Gareth Hughes <gareth@valinux.com>
*/
/*
* Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
*
* Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
* Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
#include "drmP.h"
#include <linux/interrupt.h> /* For task queue support */
/**
* Get interrupt from bus id.
*
* \param inode device inode.
* \param file_priv DRM file private.
* \param cmd command.
* \param arg user argument, pointing to a drm_irq_busid structure.
* \return zero on success or a negative number on failure.
*
* Finds the PCI device with the specified bus id and gets its IRQ number.
* This IOCTL is deprecated, and will now return EINVAL for any busid not equal
* to that of the device that this DRM instance attached to.
*/
int drm_irq_by_busid(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_irq_busid *p = data;
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return -EINVAL;
if ((p->busnum >> 8) != drm_get_pci_domain(dev) ||
(p->busnum & 0xff) != dev->pdev->bus->number ||
p->devnum != PCI_SLOT(dev->pdev->devfn) || p->funcnum != PCI_FUNC(dev->pdev->devfn))
return -EINVAL;
p->irq = dev->irq;
DRM_DEBUG("%d:%d:%d => IRQ %d\n", p->busnum, p->devnum, p->funcnum,
p->irq);
return 0;
}
static void vblank_disable_fn(unsigned long arg)
{
struct drm_device *dev = (struct drm_device *)arg;
unsigned long irqflags;
int i;
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]) {
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)
{
del_timer(&dev->vblank_disable_timer);
vblank_disable_fn((unsigned long)dev);
if (dev->vbl_queue)
drm_free(dev->vbl_queue, sizeof(*dev->vbl_queue) * dev->num_crtcs,
DRM_MEM_DRIVER);
if (dev->vbl_sigs)
drm_free(dev->vbl_sigs, sizeof(*dev->vbl_sigs) * dev->num_crtcs,
DRM_MEM_DRIVER);
if (dev->_vblank_count)
drm_free(dev->_vblank_count, sizeof(*dev->_vblank_count) *
dev->num_crtcs, DRM_MEM_DRIVER);
if (dev->vblank_refcount)
drm_free(dev->vblank_refcount, sizeof(*dev->vblank_refcount) *
dev->num_crtcs, DRM_MEM_DRIVER);
if (dev->vblank_enabled)
drm_free(dev->vblank_enabled, sizeof(*dev->vblank_enabled) *
dev->num_crtcs, DRM_MEM_DRIVER);
if (dev->last_vblank)
drm_free(dev->last_vblank, sizeof(*dev->last_vblank) * dev->num_crtcs,
DRM_MEM_DRIVER);
if (dev->vblank_premodeset)
drm_free(dev->vblank_premodeset, sizeof(*dev->vblank_premodeset) *
dev->num_crtcs, DRM_MEM_DRIVER);
if (dev->vblank_offset)
drm_free(dev->vblank_offset, sizeof(*dev->vblank_offset) * dev->num_crtcs,
DRM_MEM_DRIVER);
}
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_premodeset = drm_calloc(num_crtcs, sizeof(u32),
DRM_MEM_DRIVER);
if (!dev->vblank_premodeset)
goto err;
dev->vblank_offset = drm_calloc(num_crtcs, sizeof(u32), DRM_MEM_DRIVER);
if (!dev->vblank_offset)
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);
}
return 0;
err:
drm_vblank_cleanup(dev);
return ret;
}
EXPORT_SYMBOL(drm_vblank_init);
int drm_wait_hotplug(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
union drm_wait_hotplug *hotplugwait = data;
struct timeval now;
int ret = 0;
unsigned int flags;
if ((!dev->irq) || (!dev->irq_enabled))
return -EINVAL;
flags = hotplugwait->request.type;
if (flags & _DRM_HOTPLUG_SIGNAL) {
unsigned long irqflags;
struct list_head *hotplug_sigs = dev->hotplug_sigs;
struct drm_hotplug_sig *hotplug_sig;
hotplug_sig = drm_calloc(1, sizeof(struct drm_hotplug_sig),
DRM_MEM_DRIVER);
if (!hotplug_sig)
return -ENOMEM;
atomic_inc(&dev->hotplug_signal_pending);
hotplug_sig->info.si_signo = hotplugwait->request.signal;
hotplug_sig->task = current;
hotplug_sig->counter =
hotplugwait->reply.counter =
dev->mode_config.hotplug_counter;
spin_lock_irqsave(&dev->hotplug_lock, irqflags);
list_add_tail(&hotplug_sig->head, hotplug_sigs);
spin_unlock_irqrestore(&dev->hotplug_lock, irqflags);
} else {
int cur_hotplug = dev->mode_config.hotplug_counter;
DRM_WAIT_ON(ret, dev->hotplug_queue, 3 * DRM_HZ,
dev->mode_config.hotplug_counter > cur_hotplug);
do_gettimeofday(&now);
hotplugwait->reply.tval_sec = now.tv_sec;
hotplugwait->reply.tval_usec = now.tv_usec;
hotplugwait->reply.counter = dev->mode_config.hotplug_counter;
}
return ret;
}
static void drm_hotplug_cleanup(struct drm_device *dev)
{
if (dev->hotplug_sigs)
drm_free(dev->hotplug_sigs, sizeof(*dev->hotplug_sigs),
DRM_MEM_DRIVER);
}
EXPORT_SYMBOL(drm_hotplug_cleanup);
int drm_hotplug_init(struct drm_device *dev)
{
spin_lock_init(&dev->hotplug_lock);
atomic_set(&dev->hotplug_signal_pending, 0);
dev->hotplug_sigs = drm_alloc(sizeof(struct list_head), DRM_MEM_DRIVER);
if (!dev->hotplug_sigs)
return -ENOMEM;
INIT_LIST_HEAD(dev->hotplug_sigs);
init_waitqueue_head(&dev->hotplug_queue);
return 0;
}
EXPORT_SYMBOL(drm_hotplug_init);
/**
* Install IRQ handler.
*
* \param dev DRM device.
*
* 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.
*/
int drm_irq_install(struct drm_device * dev)
{
int ret = 0;
unsigned long sh_flags = 0;
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return -EINVAL;
if (dev->irq == 0)
return -EINVAL;
mutex_lock(&dev->struct_mutex);
/* Driver must have been initialized */
if (!dev->dev_private) {
mutex_unlock(&dev->struct_mutex);
return -EINVAL;
}
if (dev->irq_enabled) {
mutex_unlock(&dev->struct_mutex);
return 0;
}
dev->irq_enabled = 1;
mutex_unlock(&dev->struct_mutex);
DRM_DEBUG("irq=%d\n", dev->irq);
/* Before installing handler */
dev->driver->irq_preinstall(dev);
/* Install handler */
if (drm_core_check_feature(dev, DRIVER_IRQ_SHARED))
sh_flags = IRQF_SHARED;
ret = request_irq(dev->irq, dev->driver->irq_handler,
sh_flags, dev->devname, dev);
if (ret < 0) {
mutex_lock(&dev->struct_mutex);
dev->irq_enabled = 0;
mutex_unlock(&dev->struct_mutex);
return ret;
}
/* After installing handler */
ret = dev->driver->irq_postinstall(dev);
if (ret < 0) {
mutex_lock(&dev->struct_mutex);
dev->irq_enabled = 0;
mutex_unlock(&dev->struct_mutex);
}
return ret;
}
EXPORT_SYMBOL(drm_irq_install);
/**
* Uninstall the IRQ handler.
*
* \param dev DRM device.
*
* Calls the driver's \c drm_driver_irq_uninstall() function, and stops the irq.
*/
int drm_irq_uninstall(struct drm_device * dev)
{
int irq_enabled;
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return -EINVAL;
mutex_lock(&dev->struct_mutex);
irq_enabled = dev->irq_enabled;
dev->irq_enabled = 0;
mutex_unlock(&dev->struct_mutex);
if (!irq_enabled)
return -EINVAL;
DRM_DEBUG("irq=%d\n", dev->irq);
dev->driver->irq_uninstall(dev);
free_irq(dev->irq, dev);
drm_vblank_cleanup(dev);
drm_hotplug_cleanup(dev);
dev->locked_tasklet_func = NULL;
return 0;
}
EXPORT_SYMBOL(drm_irq_uninstall);
/**
* IRQ control ioctl.
*
* \param inode device inode.
* \param file_priv DRM file private.
* \param cmd command.
* \param arg user argument, pointing to a drm_control structure.
* \return zero on success or a negative number on failure.
*
* Calls irq_install() or irq_uninstall() according to \p arg.
*/
int drm_control(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_control *ctl = data;
/* if we haven't irq we fallback for compatibility reasons - this used to be a separate function in drm_dma.h */
switch (ctl->func) {
case DRM_INST_HANDLER:
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return 0;
if (drm_core_check_feature(dev, DRIVER_MODESET))
return 0;
if (dev->if_version < DRM_IF_VERSION(1, 2) &&
ctl->irq != dev->irq)
return -EINVAL;
return drm_irq_install(dev);
case DRM_UNINST_HANDLER:
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return 0;
if (drm_core_check_feature(dev, DRIVER_MODESET))
return 0;
return drm_irq_uninstall(dev);
default:
return -EINVAL;
}
}
/**
* 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]) +
dev->vblank_offset[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.
*/
void drm_update_vblank_count(struct drm_device *dev, int crtc)
{
unsigned long irqflags;
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);
spin_lock_irqsave(&dev->vbl_lock, irqflags);
if (cur_vblank < dev->last_vblank[crtc]) {
diff = dev->max_vblank_count -
dev->last_vblank[crtc];
diff += cur_vblank;
} else {
diff = cur_vblank - dev->last_vblank[crtc];
}
dev->last_vblank[crtc] = cur_vblank;
spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
atomic_add(diff, &dev->_vblank_count[crtc]);
}
EXPORT_SYMBOL(drm_update_vblank_count);
/**
* 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. Note callers will probably want to update the master counter
* using drm_update_vblank_count() above before calling this routine so that
* wakeups occur on the right vblank event.
*
* 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);
if (ret)
atomic_dec(&dev->vblank_refcount[crtc]);
else
dev->vblank_enabled[crtc] = 1;
}
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.
*/
int drm_modeset_ctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_modeset_ctl *modeset = data;
int crtc, ret = 0;
u32 new;
crtc = modeset->arg;
if (crtc >= dev->num_crtcs) {
ret = -EINVAL;
goto out;
}
switch (modeset->cmd) {
case _DRM_PRE_MODESET:
dev->vblank_premodeset[crtc] =
dev->driver->get_vblank_counter(dev, crtc);
break;
case _DRM_POST_MODESET:
new = dev->driver->get_vblank_counter(dev, crtc);
dev->vblank_offset[crtc] = dev->vblank_premodeset[crtc] - new;
break;
default:
ret = -EINVAL;
break;
}
out:
return ret;
}
/**
* Wait for VBLANK.
*
* \param inode device inode.
* \param file_priv DRM file private.
* \param cmd command.
* \param data user argument, pointing to a drm_wait_vblank structure.
* \return zero on success or a negative number on failure.
*
* Verifies the IRQ is installed.
*
* If a signal is requested checks if this task has already scheduled the same signal
* for the same vblank sequence number - nothing to be done in
* that case. If the number of tasks waiting for the interrupt exceeds 100 the
* function fails. Otherwise adds a new entry to drm_device::vbl_sigs for this
* task.
*
* 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)
{
union drm_wait_vblank *vblwait = data;
struct timeval now;
int ret = 0;
unsigned int flags, seq, crtc;
if ((!dev->irq) || (!dev->irq_enabled))
return -EINVAL;
if (vblwait->request.type &
~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK)) {
DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
vblwait->request.type,
(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK));
return -EINVAL;
}
flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
if (crtc >= dev->num_crtcs)
return -EINVAL;
drm_update_vblank_count(dev, crtc);
seq = drm_vblank_count(dev, crtc);
switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
case _DRM_VBLANK_RELATIVE:
vblwait->request.sequence += seq;
vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
case _DRM_VBLANK_ABSOLUTE:
break;
default:
return -EINVAL;
}
if ((flags & _DRM_VBLANK_NEXTONMISS) &&
(seq - vblwait->request.sequence) <= (1<<23)) {
vblwait->request.sequence = seq + 1;
}
if (flags & _DRM_VBLANK_SIGNAL) {
unsigned long irqflags;
struct list_head *vbl_sigs = &dev->vbl_sigs[crtc];
struct drm_vbl_sig *vbl_sig, *tmp;
spin_lock_irqsave(&dev->vbl_lock, irqflags);
/* Check if this task has already scheduled the same signal
* for the same vblank sequence number; nothing to be done in
* that case
*/
list_for_each_entry_safe(vbl_sig, tmp, vbl_sigs, head) {
if (vbl_sig->sequence == vblwait->request.sequence
&& vbl_sig->info.si_signo ==
vblwait->request.signal
&& vbl_sig->task == current) {
spin_unlock_irqrestore(&dev->vbl_lock,
irqflags);
vblwait->reply.sequence = seq;
goto done;
}
}
if (atomic_read(&dev->vbl_signal_pending) >= 100) {
spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
return -EBUSY;
}
spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
vbl_sig = drm_calloc(1, sizeof(struct drm_vbl_sig),
DRM_MEM_DRIVER);
if (!vbl_sig)
return -ENOMEM;
ret = drm_vblank_get(dev, crtc);
if (ret) {
drm_free(vbl_sig, sizeof(struct drm_vbl_sig),
DRM_MEM_DRIVER);
return ret;
}
atomic_inc(&dev->vbl_signal_pending);
vbl_sig->sequence = vblwait->request.sequence;
vbl_sig->info.si_signo = vblwait->request.signal;
vbl_sig->task = current;
spin_lock_irqsave(&dev->vbl_lock, irqflags);
list_add_tail(&vbl_sig->head, vbl_sigs);
spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
vblwait->reply.sequence = seq;
} else {
unsigned long cur_vblank;
ret = drm_vblank_get(dev, crtc);
if (ret)
return ret;
DRM_WAIT_ON(ret, dev->vbl_queue[crtc], 3 * DRM_HZ,
(((cur_vblank = drm_vblank_count(dev, crtc))
- vblwait->request.sequence) <= (1 << 23)));
drm_vblank_put(dev, crtc);
do_gettimeofday(&now);
vblwait->reply.tval_sec = now.tv_sec;
vblwait->reply.tval_usec = now.tv_usec;
vblwait->reply.sequence = cur_vblank;
}
done:
return ret;
}
/**
* 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().
*/
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;
spin_lock_irqsave(&dev->vbl_lock, flags);
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_del(&vbl_sig->head);
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);
}
/**
* 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)
{
drm_update_vblank_count(dev, crtc);
DRM_WAKEUP(&dev->vbl_queue[crtc]);
drm_vbl_send_signals(dev, crtc);
}
EXPORT_SYMBOL(drm_handle_vblank);
/**
* Send the HOTPLUG signals.
*
* \param dev DRM device.
*
* Sends a signal for each task in drm_device::hotplug_sigs and empties the list.
*/
static void drm_hotplug_send_signals(struct drm_device * dev)
{
struct drm_hotplug_sig *hotplug_sig, *tmp;
struct list_head *hotplug_sigs;
unsigned long flags;
spin_lock_irqsave(&dev->hotplug_lock, flags);
hotplug_sigs = dev->hotplug_sigs;
list_for_each_entry_safe(hotplug_sig, tmp, hotplug_sigs, head) {
hotplug_sig->info.si_code = hotplug_sig->counter;
send_sig_info(hotplug_sig->info.si_signo,
&hotplug_sig->info, hotplug_sig->task);
list_del(&hotplug_sig->head);
drm_free(hotplug_sig, sizeof(*hotplug_sig),
DRM_MEM_DRIVER);
atomic_dec(&dev->hotplug_signal_pending);
}
spin_unlock_irqrestore(&dev->hotplug_lock, flags);
}
/**
* drm_handle_hotplug - handle a hotplug event
* @dev: DRM device
* @crtc: where this event occurred
*
* Drivers should call this routine in their hotplug interrupt handlers.
*/
void drm_handle_hotplug(struct drm_device *dev)
{
DRM_WAKEUP(&dev->hotplug_queue);
drm_hotplug_send_signals(dev);
}
EXPORT_SYMBOL(drm_handle_hotplug);
/**
* Tasklet wrapper function.
*
* \param data DRM device in disguise.
*
* Attempts to grab the HW lock and calls the driver callback on success. On
* failure, leave the lock marked as contended so the callback can be called
* from drm_unlock().
*/
static void drm_locked_tasklet_func(unsigned long data)
{
struct drm_device *dev = (struct drm_device *)data;
unsigned long irqflags;
spin_lock_irqsave(&dev->tasklet_lock, irqflags);
if (!dev->locked_tasklet_func ||
!drm_lock_take(&dev->primary->master->lock,
DRM_KERNEL_CONTEXT)) {
spin_unlock_irqrestore(&dev->tasklet_lock, irqflags);
return;
}
dev->primary->master->lock.lock_time = jiffies;
atomic_inc(&dev->counts[_DRM_STAT_LOCKS]);
dev->locked_tasklet_func(dev);
drm_lock_free(&dev->primary->master->lock,
DRM_KERNEL_CONTEXT);
dev->locked_tasklet_func = NULL;
spin_unlock_irqrestore(&dev->tasklet_lock, irqflags);
}
/**
* Schedule a tasklet to call back a driver hook with the HW lock held.
*
* \param dev DRM device.
* \param func Driver callback.
*
* This is intended for triggering actions that require the HW lock from an
* interrupt handler. The lock will be grabbed ASAP after the interrupt handler
* completes. Note that the callback may be called from interrupt or process
* context, it must not make any assumptions about this. Also, the HW lock will
* be held with the kernel context or any client context.
*/
void drm_locked_tasklet(struct drm_device *dev, void (*func)(struct drm_device *))
{
unsigned long irqflags;
static DECLARE_TASKLET(drm_tasklet, drm_locked_tasklet_func, 0);
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ) ||
test_bit(TASKLET_STATE_SCHED, &drm_tasklet.state))
return;
spin_lock_irqsave(&dev->tasklet_lock, irqflags);
if (dev->locked_tasklet_func) {
spin_unlock_irqrestore(&dev->tasklet_lock, irqflags);
return;
}
dev->locked_tasklet_func = func;
spin_unlock_irqrestore(&dev->tasklet_lock, irqflags);
drm_tasklet.data = (unsigned long)dev;
tasklet_hi_schedule(&drm_tasklet);
}
EXPORT_SYMBOL(drm_locked_tasklet);
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