drivers/base/power/wakeup_stats.c

   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
  21 static struct class *wakeup_class;
  22
  23 #define wakeup_attr(_name)                                              \
  24 static 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 }                                                                       \
  31 static DEVICE_ATTR_RO(_name)
  32
  33 wakeup_attr(active_count);
  34 wakeup_attr(event_count);
  35 wakeup_attr(wakeup_count);
  36 wakeup_attr(expire_count);
  37
  38 static 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 }
  47 static DEVICE_ATTR_RO(active_time_ms);
  48
  49 static 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 }
  63 static DEVICE_ATTR_RO(total_time_ms);
  64
  65 static 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 }
  80 static DEVICE_ATTR_RO(max_time_ms);
  81
  82 static 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 }
  89 static DEVICE_ATTR_RO(last_change_ms);
  90
  91 static 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 }
  98 static DEVICE_ATTR_RO(name);
  99
 100 static 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 }
 114 static DEVICE_ATTR_RO(prevent_suspend_time_ms);
 115
 116 static 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 };
 129 ATTRIBUTE_GROUPS(wakeup_source);
 130
 131 static void device_create_release(struct device *dev)
 132 {
 133         kfree(dev);
 134 }
 135
 136 static 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
 167 error:
 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  */
 177 int 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  */
 194 int 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  */
 206 void wakeup_source_sysfs_remove(struct wakeup_source *ws)
 207 {
 208         device_unregister(ws->dev);
 209 }
 210
 211 static 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 }
 217 postcore_initcall(wakeup_sources_sysfs_init);