diff options
Diffstat (limited to 'linux-core/drm_irq.c')
| -rw-r--r-- | linux-core/drm_irq.c | 769 |
1 files changed, 0 insertions, 769 deletions
diff --git a/linux-core/drm_irq.c b/linux-core/drm_irq.c deleted file mode 100644 index 64fffd9c..00000000 --- a/linux-core/drm_irq.c +++ /dev/null @@ -1,769 +0,0 @@ -/** - * \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->pdev->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; - - 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); - } -} - -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); - init_timer_deferrable(&dev->vblank_disable_timer); - 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. - * - * 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->pdev->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 -EBUSY; - } - dev->irq_enabled = 1; - mutex_unlock(&dev->struct_mutex); - - DRM_DEBUG("irq=%d\n", dev->pdev->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->pdev->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; - } - /* Expose the device irq to device drivers that want to export it for - * whatever reason. - */ - dev->irq = dev->pdev->irq; - - /* 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->pdev->irq); - - dev->driver->irq_uninstall(dev); - - free_irq(dev->pdev->irq, 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 (dev->if_version < DRM_IF_VERSION(1, 2) && - ctl->irq != dev->pdev->irq) - return -EINVAL; - return drm_irq_install(dev); - case DRM_UNINST_HANDLER: - if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) - 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]); -} -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); - 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. - * \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; - int ret = 0; - unsigned int flags, seq, crtc; - - if ((!dev->pdev->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; - - ret = drm_vblank_get(dev, crtc); - if (ret) - return ret; - 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: - ret = -EINVAL; - goto done; - } - - 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; - - 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(vbl_sig, 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); - ret = -EBUSY; - goto done; - } - - spin_unlock_irqrestore(&dev->vbl_lock, irqflags); - - 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; - } - - 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 { - 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); - } - } - -done: - drm_vblank_put(dev, crtc); - 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) -{ - 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. - * - * \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; - void (*tasklet_func)(struct drm_device *); - - spin_lock_irqsave(&dev->tasklet_lock, irqflags); - tasklet_func = dev->locked_tasklet_func; - spin_unlock_irqrestore(&dev->tasklet_lock, irqflags); - - if (!tasklet_func || - !drm_lock_take(&dev->lock, - DRM_KERNEL_CONTEXT)) { - return; - } - - dev->lock.lock_time = jiffies; - atomic_inc(&dev->counts[_DRM_STAT_LOCKS]); - - spin_lock_irqsave(&dev->tasklet_lock, irqflags); - tasklet_func = dev->locked_tasklet_func; - dev->locked_tasklet_func = NULL; - spin_unlock_irqrestore(&dev->tasklet_lock, irqflags); - - if (tasklet_func != NULL) - tasklet_func(dev); - - drm_lock_free(&dev->lock, - DRM_KERNEL_CONTEXT); -} - -/** - * 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); |