v4.19.13 snapshot.
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
new file mode 100644
index 0000000..3b04c25
--- /dev/null
+++ b/drivers/gpu/drm/drm_irq.c
@@ -0,0 +1,261 @@
+/*
+ * drm_irq.c IRQ and vblank support
+ *
+ * \author Rickard E. (Rik) Faith <faith@valinux.com>
+ * \author Gareth Hughes <gareth@valinux.com>
+ *
+ * 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.
+ */
+
+/*
+ * 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 <drm/drm_irq.h>
+#include <drm/drmP.h>
+
+#include <linux/interrupt.h> /* For task queue support */
+
+#include <linux/vgaarb.h>
+#include <linux/export.h>
+
+#include "drm_internal.h"
+
+/**
+ * DOC: irq helpers
+ *
+ * The DRM core provides very simple support helpers to enable IRQ handling on a
+ * device through the drm_irq_install() and drm_irq_uninstall() functions. This
+ * only supports devices with a single interrupt on the main device stored in
+ * &drm_device.dev and set as the device paramter in drm_dev_alloc().
+ *
+ * These IRQ helpers are strictly optional. Drivers which roll their own only
+ * need to set &drm_device.irq_enabled to signal the DRM core that vblank
+ * interrupts are working. Since these helpers don't automatically clean up the
+ * requested interrupt like e.g. devm_request_irq() they're not really
+ * recommended.
+ */
+
+/**
+ * drm_irq_install - install IRQ handler
+ * @dev: DRM device
+ * @irq: IRQ number to install the handler for
+ *
+ * Initializes the IRQ related data. Installs the handler, calling the driver
+ * &drm_driver.irq_preinstall and &drm_driver.irq_postinstall functions before
+ * and after the installation.
+ *
+ * This is the simplified helper interface provided for drivers with no special
+ * needs. Drivers which need to install interrupt handlers for multiple
+ * interrupts must instead set &drm_device.irq_enabled to signal the DRM core
+ * that vblank interrupts are available.
+ *
+ * @irq must match the interrupt number that would be passed to request_irq(),
+ * if called directly instead of using this helper function.
+ *
+ * &drm_driver.irq_handler is called to handle the registered interrupt.
+ *
+ * Returns:
+ * Zero on success or a negative error code on failure.
+ */
+int drm_irq_install(struct drm_device *dev, int irq)
+{
+ int ret;
+ unsigned long sh_flags = 0;
+
+ if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
+ return -EINVAL;
+
+ if (irq == 0)
+ return -EINVAL;
+
+ /* Driver must have been initialized */
+ if (!dev->dev_private)
+ return -EINVAL;
+
+ if (dev->irq_enabled)
+ return -EBUSY;
+ dev->irq_enabled = true;
+
+ DRM_DEBUG("irq=%d\n", irq);
+
+ /* Before installing handler */
+ if (dev->driver->irq_preinstall)
+ dev->driver->irq_preinstall(dev);
+
+ /* Install handler */
+ if (drm_core_check_feature(dev, DRIVER_IRQ_SHARED))
+ sh_flags = IRQF_SHARED;
+
+ ret = request_irq(irq, dev->driver->irq_handler,
+ sh_flags, dev->driver->name, dev);
+
+ if (ret < 0) {
+ dev->irq_enabled = false;
+ return ret;
+ }
+
+ /* After installing handler */
+ if (dev->driver->irq_postinstall)
+ ret = dev->driver->irq_postinstall(dev);
+
+ if (ret < 0) {
+ dev->irq_enabled = false;
+ if (drm_core_check_feature(dev, DRIVER_LEGACY))
+ vga_client_register(dev->pdev, NULL, NULL, NULL);
+ free_irq(irq, dev);
+ } else {
+ dev->irq = irq;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(drm_irq_install);
+
+/**
+ * drm_irq_uninstall - uninstall the IRQ handler
+ * @dev: DRM device
+ *
+ * Calls the driver's &drm_driver.irq_uninstall function and unregisters the IRQ
+ * handler. This should only be called by drivers which used drm_irq_install()
+ * to set up their interrupt handler. Other drivers must only reset
+ * &drm_device.irq_enabled to false.
+ *
+ * Note that for kernel modesetting drivers it is a bug if this function fails.
+ * The sanity checks are only to catch buggy user modesetting drivers which call
+ * the same function through an ioctl.
+ *
+ * Returns:
+ * Zero on success or a negative error code on failure.
+ */
+int drm_irq_uninstall(struct drm_device *dev)
+{
+ unsigned long irqflags;
+ bool irq_enabled;
+ int i;
+
+ if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
+ return -EINVAL;
+
+ irq_enabled = dev->irq_enabled;
+ dev->irq_enabled = false;
+
+ /*
+ * Wake up any waiters so they don't hang. This is just to paper over
+ * issues for UMS drivers which aren't in full control of their
+ * vblank/irq handling. KMS drivers must ensure that vblanks are all
+ * disabled when uninstalling the irq handler.
+ */
+ if (dev->num_crtcs) {
+ spin_lock_irqsave(&dev->vbl_lock, irqflags);
+ for (i = 0; i < dev->num_crtcs; i++) {
+ struct drm_vblank_crtc *vblank = &dev->vblank[i];
+
+ if (!vblank->enabled)
+ continue;
+
+ WARN_ON(drm_core_check_feature(dev, DRIVER_MODESET));
+
+ drm_vblank_disable_and_save(dev, i);
+ wake_up(&vblank->queue);
+ }
+ spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
+ }
+
+ if (!irq_enabled)
+ return -EINVAL;
+
+ DRM_DEBUG("irq=%d\n", dev->irq);
+
+ if (drm_core_check_feature(dev, DRIVER_LEGACY))
+ vga_client_register(dev->pdev, NULL, NULL, NULL);
+
+ if (dev->driver->irq_uninstall)
+ dev->driver->irq_uninstall(dev);
+
+ free_irq(dev->irq, dev);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_irq_uninstall);
+
+int drm_legacy_irq_control(struct drm_device *dev, void *data,
+ struct drm_file *file_priv)
+{
+ struct drm_control *ctl = data;
+ int ret = 0, irq;
+
+ /* if we haven't irq we fallback for compatibility reasons -
+ * this used to be a separate function in drm_dma.h
+ */
+
+ if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
+ return 0;
+ if (!drm_core_check_feature(dev, DRIVER_LEGACY))
+ return 0;
+ /* UMS was only ever supported on pci devices. */
+ if (WARN_ON(!dev->pdev))
+ return -EINVAL;
+
+ switch (ctl->func) {
+ case DRM_INST_HANDLER:
+ irq = dev->pdev->irq;
+
+ if (dev->if_version < DRM_IF_VERSION(1, 2) &&
+ ctl->irq != irq)
+ return -EINVAL;
+ mutex_lock(&dev->struct_mutex);
+ ret = drm_irq_install(dev, irq);
+ mutex_unlock(&dev->struct_mutex);
+
+ return ret;
+ case DRM_UNINST_HANDLER:
+ mutex_lock(&dev->struct_mutex);
+ ret = drm_irq_uninstall(dev);
+ mutex_unlock(&dev->struct_mutex);
+
+ return ret;
+ default:
+ return -EINVAL;
+ }
+}