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, handler: dev->driver->irq_handler,
92 flags: sh_flags, name: 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, feature: 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, pipe: i);
141 wake_up(&vblank->queue);
142 }
143 spin_unlock_irqrestore(lock: &dev->vbl_lock, flags: 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, feature: 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, feature: DRIVER_HAVE_IRQ))
175 return 0;
176 if (!drm_core_check_feature(dev, feature: 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(lock: &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(lock: &dev->struct_mutex);
199
200 return ret;
201 default:
202 return -EINVAL;
203 }
204}
205

source code of linux/drivers/gpu/drm/drm_irq.c