1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Wakeup statistics in sysfs
4 *
5 * Copyright (c) 2019 Linux Foundation
6 * Copyright (c) 2019 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
7 * Copyright (c) 2019 Google Inc.
8 */
9
10#include <linux/device.h>
11#include <linux/idr.h>
12#include <linux/init.h>
13#include <linux/kdev_t.h>
14#include <linux/kernel.h>
15#include <linux/kobject.h>
16#include <linux/slab.h>
17#include <linux/timekeeping.h>
18
19#include "power.h"
20
21static struct class *wakeup_class;
22
23#define wakeup_attr(_name) \
24static ssize_t _name##_show(struct device *dev, \
25 struct device_attribute *attr, char *buf) \
26{ \
27 struct wakeup_source *ws = dev_get_drvdata(dev); \
28 \
29 return sysfs_emit(buf, "%lu\n", ws->_name); \
30} \
31static DEVICE_ATTR_RO(_name)
32
33wakeup_attr(active_count);
34wakeup_attr(event_count);
35wakeup_attr(wakeup_count);
36wakeup_attr(expire_count);
37
38static ssize_t active_time_ms_show(struct device *dev,
39 struct device_attribute *attr, char *buf)
40{
41 struct wakeup_source *ws = dev_get_drvdata(dev);
42 ktime_t active_time =
43 ws->active ? ktime_sub(ktime_get(), ws->last_time) : 0;
44
45 return sysfs_emit(buf, fmt: "%lld\n", ktime_to_ms(kt: active_time));
46}
47static DEVICE_ATTR_RO(active_time_ms);
48
49static ssize_t total_time_ms_show(struct device *dev,
50 struct device_attribute *attr, char *buf)
51{
52 struct wakeup_source *ws = dev_get_drvdata(dev);
53 ktime_t active_time;
54 ktime_t total_time = ws->total_time;
55
56 if (ws->active) {
57 active_time = ktime_sub(ktime_get(), ws->last_time);
58 total_time = ktime_add(total_time, active_time);
59 }
60
61 return sysfs_emit(buf, fmt: "%lld\n", ktime_to_ms(kt: total_time));
62}
63static DEVICE_ATTR_RO(total_time_ms);
64
65static ssize_t max_time_ms_show(struct device *dev,
66 struct device_attribute *attr, char *buf)
67{
68 struct wakeup_source *ws = dev_get_drvdata(dev);
69 ktime_t active_time;
70 ktime_t max_time = ws->max_time;
71
72 if (ws->active) {
73 active_time = ktime_sub(ktime_get(), ws->last_time);
74 if (active_time > max_time)
75 max_time = active_time;
76 }
77
78 return sysfs_emit(buf, fmt: "%lld\n", ktime_to_ms(kt: max_time));
79}
80static DEVICE_ATTR_RO(max_time_ms);
81
82static ssize_t last_change_ms_show(struct device *dev,
83 struct device_attribute *attr, char *buf)
84{
85 struct wakeup_source *ws = dev_get_drvdata(dev);
86
87 return sysfs_emit(buf, fmt: "%lld\n", ktime_to_ms(kt: ws->last_time));
88}
89static DEVICE_ATTR_RO(last_change_ms);
90
91static ssize_t name_show(struct device *dev, struct device_attribute *attr,
92 char *buf)
93{
94 struct wakeup_source *ws = dev_get_drvdata(dev);
95
96 return sysfs_emit(buf, fmt: "%s\n", ws->name);
97}
98static DEVICE_ATTR_RO(name);
99
100static ssize_t prevent_suspend_time_ms_show(struct device *dev,
101 struct device_attribute *attr,
102 char *buf)
103{
104 struct wakeup_source *ws = dev_get_drvdata(dev);
105 ktime_t prevent_sleep_time = ws->prevent_sleep_time;
106
107 if (ws->active && ws->autosleep_enabled) {
108 prevent_sleep_time = ktime_add(prevent_sleep_time,
109 ktime_sub(ktime_get(), ws->start_prevent_time));
110 }
111
112 return sysfs_emit(buf, fmt: "%lld\n", ktime_to_ms(kt: prevent_sleep_time));
113}
114static DEVICE_ATTR_RO(prevent_suspend_time_ms);
115
116static struct attribute *wakeup_source_attrs[] = {
117 &dev_attr_name.attr,
118 &dev_attr_active_count.attr,
119 &dev_attr_event_count.attr,
120 &dev_attr_wakeup_count.attr,
121 &dev_attr_expire_count.attr,
122 &dev_attr_active_time_ms.attr,
123 &dev_attr_total_time_ms.attr,
124 &dev_attr_max_time_ms.attr,
125 &dev_attr_last_change_ms.attr,
126 &dev_attr_prevent_suspend_time_ms.attr,
127 NULL,
128};
129ATTRIBUTE_GROUPS(wakeup_source);
130
131static void device_create_release(struct device *dev)
132{
133 kfree(objp: dev);
134}
135
136static struct device *wakeup_source_device_create(struct device *parent,
137 struct wakeup_source *ws)
138{
139 struct device *dev = NULL;
140 int retval;
141
142 dev = kzalloc(size: sizeof(*dev), GFP_KERNEL);
143 if (!dev) {
144 retval = -ENOMEM;
145 goto error;
146 }
147
148 device_initialize(dev);
149 dev->devt = MKDEV(0, 0);
150 dev->class = wakeup_class;
151 dev->parent = parent;
152 dev->groups = wakeup_source_groups;
153 dev->release = device_create_release;
154 dev_set_drvdata(dev, data: ws);
155 device_set_pm_not_required(dev);
156
157 retval = dev_set_name(dev, name: "wakeup%d", ws->id);
158 if (retval)
159 goto error;
160
161 retval = device_add(dev);
162 if (retval)
163 goto error;
164
165 return dev;
166
167error:
168 put_device(dev);
169 return ERR_PTR(error: retval);
170}
171
172/**
173 * wakeup_source_sysfs_add - Add wakeup_source attributes to sysfs.
174 * @parent: Device given wakeup source is associated with (or NULL if virtual).
175 * @ws: Wakeup source to be added in sysfs.
176 */
177int wakeup_source_sysfs_add(struct device *parent, struct wakeup_source *ws)
178{
179 struct device *dev;
180
181 dev = wakeup_source_device_create(parent, ws);
182 if (IS_ERR(ptr: dev))
183 return PTR_ERR(ptr: dev);
184 ws->dev = dev;
185
186 return 0;
187}
188
189/**
190 * pm_wakeup_source_sysfs_add - Add wakeup_source attributes to sysfs
191 * for a device if they're missing.
192 * @parent: Device given wakeup source is associated with
193 */
194int pm_wakeup_source_sysfs_add(struct device *parent)
195{
196 if (!parent->power.wakeup || parent->power.wakeup->dev)
197 return 0;
198
199 return wakeup_source_sysfs_add(parent, ws: parent->power.wakeup);
200}
201
202/**
203 * wakeup_source_sysfs_remove - Remove wakeup_source attributes from sysfs.
204 * @ws: Wakeup source to be removed from sysfs.
205 */
206void wakeup_source_sysfs_remove(struct wakeup_source *ws)
207{
208 device_unregister(dev: ws->dev);
209}
210
211static int __init wakeup_sources_sysfs_init(void)
212{
213 wakeup_class = class_create(name: "wakeup");
214
215 return PTR_ERR_OR_ZERO(ptr: wakeup_class);
216}
217postcore_initcall(wakeup_sources_sysfs_init);
218

source code of linux/drivers/base/power/wakeup_stats.c