1/*
  2 * drm_irq.c IRQ and vblank support
  3 *
  4 * \author Rickard E. (Rik) Faith <faith@valinux.com>
  5 * \author Gareth Hughes <gareth@valinux.com>
  6 *
  7 * Permission is hereby granted, free of charge, to any person obtaining a
  8 * copy of this software and associated documentation files (the "Software"),
  9 * to deal in the Software without restriction, including without limitation
 10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 11 * and/or sell copies of the Software, and to permit persons to whom the
 12 * Software is furnished to do so, subject to the following conditions:
 13 *
 14 * The above copyright notice and this permission notice (including the next
 15 * paragraph) shall be included in all copies or substantial portions of the
 16 * Software.
 17 *
 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 21 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 22 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 23 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 24 * OTHER DEALINGS IN THE SOFTWARE.
 25 */
 26
 27/*
 28 * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
 29 *
 30 * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
 31 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 32 * All Rights Reserved.
 33 *
 34 * Permission is hereby granted, free of charge, to any person obtaining a
 35 * copy of this software and associated documentation files (the "Software"),
 36 * to deal in the Software without restriction, including without limitation
 37 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 38 * and/or sell copies of the Software, and to permit persons to whom the
 39 * Software is furnished to do so, subject to the following conditions:
 40 *
 41 * The above copyright notice and this permission notice (including the next
 42 * paragraph) shall be included in all copies or substantial portions of the
 43 * Software.
 44 *
 45 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 46 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 47 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 48 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 49 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 50 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 51 * OTHER DEALINGS IN THE SOFTWARE.
 52 */
 53
 54
 55#include <linux/export.h>
 56#include <linux/interrupt.h>	/* For task queue support */
 57#include <linux/pci.h>
 58#include <linux/vgaarb.h>
 59
 60#include <drm/drm.h>
 61#include <drm/drm_device.h>
 62#include <drm/drm_drv.h>
 63#include <drm/drm_legacy.h>
 64#include <drm/drm_print.h>
 65#include <drm/drm_vblank.h>
 66
 67#include "drm_internal.h"
 68
 69static int drm_legacy_irq_install(struct drm_device *dev, int irq)
 70{
 71	int ret;
 72	unsigned long sh_flags = 0;
 73
 74	if (irq == 0)
 75		return -EINVAL;
 76
 77	if (dev->irq_enabled)
 78		return -EBUSY;
 79	dev->irq_enabled = true;
 80
 81	DRM_DEBUG("irq=%d\n", irq);
 82
 83	/* Before installing handler */
 84	if (dev->driver->irq_preinstall)
 85		dev->driver->irq_preinstall(dev);
 86
 87	/* PCI devices require shared interrupts. */
 88	if (dev_is_pci(dev->dev))
 89		sh_flags = IRQF_SHARED;
 90
 91	ret = request_irq(irq, dev->driver->irq_handler,
 92			  sh_flags, dev->driver->name, dev);
 93
 94	if (ret < 0) {
 95		dev->irq_enabled = false;
 96		return ret;
 97	}
 98
 99	/* After installing handler */
100	if (dev->driver->irq_postinstall)
101		ret = dev->driver->irq_postinstall(dev);
102
103	if (ret < 0) {
104		dev->irq_enabled = false;
105		if (drm_core_check_feature(dev, DRIVER_LEGACY))
106			vga_client_unregister(to_pci_dev(dev->dev));
107		free_irq(irq, dev);
108	} else {
109		dev->irq = irq;
110	}
111
112	return ret;
113}
114
115int drm_legacy_irq_uninstall(struct drm_device *dev)
116{
117	unsigned long irqflags;
118	bool irq_enabled;
119	int i;
120
121	irq_enabled = dev->irq_enabled;
122	dev->irq_enabled = false;
123
124	/*
125	 * Wake up any waiters so they don't hang. This is just to paper over
126	 * issues for UMS drivers which aren't in full control of their
127	 * vblank/irq handling. KMS drivers must ensure that vblanks are all
128	 * disabled when uninstalling the irq handler.
129	 */
130	if (drm_dev_has_vblank(dev)) {
131		spin_lock_irqsave(&dev->vbl_lock, irqflags);
132		for (i = 0; i < dev->num_crtcs; i++) {
133			struct drm_vblank_crtc *vblank = &dev->vblank[i];
134
135			if (!vblank->enabled)
136				continue;
137
138			WARN_ON(drm_core_check_feature(dev, DRIVER_MODESET));
139
140			drm_vblank_disable_and_save(dev, i);
141			wake_up(&vblank->queue);
142		}
143		spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
144	}
145
146	if (!irq_enabled)
147		return -EINVAL;
148
149	DRM_DEBUG("irq=%d\n", dev->irq);
150
151	if (drm_core_check_feature(dev, DRIVER_LEGACY))
152		vga_client_unregister(to_pci_dev(dev->dev));
153
154	if (dev->driver->irq_uninstall)
155		dev->driver->irq_uninstall(dev);
156
157	free_irq(dev->irq, dev);
158
159	return 0;
160}
161EXPORT_SYMBOL(drm_legacy_irq_uninstall);
162
163int drm_legacy_irq_control(struct drm_device *dev, void *data,
164			   struct drm_file *file_priv)
165{
166	struct drm_control *ctl = data;
167	int ret = 0, irq;
168	struct pci_dev *pdev;
169
170	/* if we haven't irq we fallback for compatibility reasons -
171	 * this used to be a separate function in drm_dma.h
172	 */
173
174	if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
175		return 0;
176	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
177		return 0;
178	/* UMS was only ever supported on pci devices. */
179	if (WARN_ON(!dev_is_pci(dev->dev)))
180		return -EINVAL;
181
182	switch (ctl->func) {
183	case DRM_INST_HANDLER:
184		pdev = to_pci_dev(dev->dev);
185		irq = pdev->irq;
186
187		if (dev->if_version < DRM_IF_VERSION(1, 2) &&
188		    ctl->irq != irq)
189			return -EINVAL;
190		mutex_lock(&dev->struct_mutex);
191		ret = drm_legacy_irq_install(dev, irq);
192		mutex_unlock(&dev->struct_mutex);
193
194		return ret;
195	case DRM_UNINST_HANDLER:
196		mutex_lock(&dev->struct_mutex);
197		ret = drm_legacy_irq_uninstall(dev);
198		mutex_unlock(&dev->struct_mutex);
199
200		return ret;
201	default:
202		return -EINVAL;
203	}
204}