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authorJonathan Herman <hermanjl@cs.unc.edu>2013-01-22 10:38:37 -0500
committerJonathan Herman <hermanjl@cs.unc.edu>2013-01-22 10:38:37 -0500
commitfcc9d2e5a6c89d22b8b773a64fb4ad21ac318446 (patch)
treea57612d1888735a2ec7972891b68c1ac5ec8faea /kernel/power/fbearlysuspend.c
parent8dea78da5cee153b8af9c07a2745f6c55057fe12 (diff)
Added missing tegra files.HEADmaster
Diffstat (limited to 'kernel/power/fbearlysuspend.c')
-rw-r--r--kernel/power/fbearlysuspend.c153
1 files changed, 153 insertions, 0 deletions
diff --git a/kernel/power/fbearlysuspend.c b/kernel/power/fbearlysuspend.c
new file mode 100644
index 00000000000..15137650149
--- /dev/null
+++ b/kernel/power/fbearlysuspend.c
@@ -0,0 +1,153 @@
1/* kernel/power/fbearlysuspend.c
2 *
3 * Copyright (C) 2005-2008 Google, Inc.
4 *
5 * This software is licensed under the terms of the GNU General Public
6 * License version 2, as published by the Free Software Foundation, and
7 * may be copied, distributed, and modified under those terms.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 */
15
16#include <linux/earlysuspend.h>
17#include <linux/module.h>
18#include <linux/wait.h>
19
20#include "power.h"
21
22static wait_queue_head_t fb_state_wq;
23static DEFINE_SPINLOCK(fb_state_lock);
24static enum {
25 FB_STATE_STOPPED_DRAWING,
26 FB_STATE_REQUEST_STOP_DRAWING,
27 FB_STATE_DRAWING_OK,
28} fb_state;
29
30/* tell userspace to stop drawing, wait for it to stop */
31static void stop_drawing_early_suspend(struct early_suspend *h)
32{
33 int ret;
34 unsigned long irq_flags;
35
36 spin_lock_irqsave(&fb_state_lock, irq_flags);
37 fb_state = FB_STATE_REQUEST_STOP_DRAWING;
38 spin_unlock_irqrestore(&fb_state_lock, irq_flags);
39
40 wake_up_all(&fb_state_wq);
41 ret = wait_event_timeout(fb_state_wq,
42 fb_state == FB_STATE_STOPPED_DRAWING,
43 HZ);
44 if (unlikely(fb_state != FB_STATE_STOPPED_DRAWING))
45 pr_warning("stop_drawing_early_suspend: timeout waiting for "
46 "userspace to stop drawing\n");
47}
48
49/* tell userspace to start drawing */
50static void start_drawing_late_resume(struct early_suspend *h)
51{
52 unsigned long irq_flags;
53
54 spin_lock_irqsave(&fb_state_lock, irq_flags);
55 fb_state = FB_STATE_DRAWING_OK;
56 spin_unlock_irqrestore(&fb_state_lock, irq_flags);
57 wake_up(&fb_state_wq);
58}
59
60static struct early_suspend stop_drawing_early_suspend_desc = {
61 .level = EARLY_SUSPEND_LEVEL_STOP_DRAWING,
62 .suspend = stop_drawing_early_suspend,
63 .resume = start_drawing_late_resume,
64};
65
66static ssize_t wait_for_fb_sleep_show(struct kobject *kobj,
67 struct kobj_attribute *attr, char *buf)
68{
69 char *s = buf;
70 int ret;
71
72 ret = wait_event_interruptible(fb_state_wq,
73 fb_state != FB_STATE_DRAWING_OK);
74 if (ret && fb_state == FB_STATE_DRAWING_OK)
75 return ret;
76 else
77 s += sprintf(buf, "sleeping");
78 return s - buf;
79}
80
81static ssize_t wait_for_fb_wake_show(struct kobject *kobj,
82 struct kobj_attribute *attr, char *buf)
83{
84 char *s = buf;
85 int ret;
86 unsigned long irq_flags;
87
88 spin_lock_irqsave(&fb_state_lock, irq_flags);
89 if (fb_state == FB_STATE_REQUEST_STOP_DRAWING) {
90 fb_state = FB_STATE_STOPPED_DRAWING;
91 wake_up(&fb_state_wq);
92 }
93 spin_unlock_irqrestore(&fb_state_lock, irq_flags);
94
95 ret = wait_event_interruptible(fb_state_wq,
96 fb_state == FB_STATE_DRAWING_OK);
97 if (ret && fb_state != FB_STATE_DRAWING_OK)
98 return ret;
99 else
100 s += sprintf(buf, "awake");
101
102 return s - buf;
103}
104
105#define power_ro_attr(_name) \
106static struct kobj_attribute _name##_attr = { \
107 .attr = { \
108 .name = __stringify(_name), \
109 .mode = 0444, \
110 }, \
111 .show = _name##_show, \
112 .store = NULL, \
113}
114
115power_ro_attr(wait_for_fb_sleep);
116power_ro_attr(wait_for_fb_wake);
117
118static struct attribute *g[] = {
119 &wait_for_fb_sleep_attr.attr,
120 &wait_for_fb_wake_attr.attr,
121 NULL,
122};
123
124static struct attribute_group attr_group = {
125 .attrs = g,
126};
127
128static int __init android_power_init(void)
129{
130 int ret;
131
132 init_waitqueue_head(&fb_state_wq);
133 fb_state = FB_STATE_DRAWING_OK;
134
135 ret = sysfs_create_group(power_kobj, &attr_group);
136 if (ret) {
137 pr_err("android_power_init: sysfs_create_group failed\n");
138 return ret;
139 }
140
141 register_early_suspend(&stop_drawing_early_suspend_desc);
142 return 0;
143}
144
145static void __exit android_power_exit(void)
146{
147 unregister_early_suspend(&stop_drawing_early_suspend_desc);
148 sysfs_remove_group(power_kobj, &attr_group);
149}
150
151module_init(android_power_init);
152module_exit(android_power_exit);
153