LXR linux/drivers/base/power/wakeup

   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, "%lld\n", ktime_to_ms(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, "%lld\n", ktime_to_ms(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, "%lld\n", ktime_to_ms(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, "%lld\n", ktime_to_ms(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, "%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, "%lld\n", ktime_to_ms(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(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(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, ws);
 155        device_set_pm_not_required(dev);
 156
 157        retval = dev_set_name(dev, "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(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(dev))
 183                return PTR_ERR(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, 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(ws->dev);
 209}
 210
 211static int __init wakeup_sources_sysfs_init(void)
 212{
 213        wakeup_class = class_create(THIS_MODULE, "wakeup");
 214
 215        return PTR_ERR_OR_ZERO(wakeup_class);
 216}
 217postcore_initcall(wakeup_sources_sysfs_init);
 218