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 sprintf(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 sprintf(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         return sprintf(buf, "%lld\n", ktime_to_ms(total_time));
  61 }
  62 static DEVICE_ATTR_RO(total_time_ms);
  63
  64 static ssize_t max_time_ms_show(struct device *dev,
  65                                 struct device_attribute *attr, char *buf)
  66 {
  67         struct wakeup_source *ws = dev_get_drvdata(dev);
  68         ktime_t active_time;
  69         ktime_t max_time = ws->max_time;
  70
  71         if (ws->active) {
  72                 active_time = ktime_sub(ktime_get(), ws->last_time);
  73                 if (active_time > max_time)
  74                         max_time = active_time;
  75         }
  76         return sprintf(buf, "%lld\n", ktime_to_ms(max_time));
  77 }
  78 static DEVICE_ATTR_RO(max_time_ms);
  79
  80 static ssize_t last_change_ms_show(struct device *dev,
  81                                    struct device_attribute *attr, char *buf)
  82 {
  83         struct wakeup_source *ws = dev_get_drvdata(dev);
  84
  85         return sprintf(buf, "%lld\n", ktime_to_ms(ws->last_time));
  86 }
  87 static DEVICE_ATTR_RO(last_change_ms);
  88
  89 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
  90                          char *buf)
  91 {
  92         struct wakeup_source *ws = dev_get_drvdata(dev);
  93
  94         return sprintf(buf, "%s\n", ws->name);
  95 }
  96 static DEVICE_ATTR_RO(name);
  97
  98 static ssize_t prevent_suspend_time_ms_show(struct device *dev,
  99                                             struct device_attribute *attr,
 100                                             char *buf)
 101 {
 102         struct wakeup_source *ws = dev_get_drvdata(dev);
 103         ktime_t prevent_sleep_time = ws->prevent_sleep_time;
 104
 105         if (ws->active && ws->autosleep_enabled) {
 106                 prevent_sleep_time = ktime_add(prevent_sleep_time,
 107                         ktime_sub(ktime_get(), ws->start_prevent_time));
 108         }
 109         return sprintf(buf, "%lld\n", ktime_to_ms(prevent_sleep_time));
 110 }
 111 static DEVICE_ATTR_RO(prevent_suspend_time_ms);
 112
 113 static struct attribute *wakeup_source_attrs[] = {
 114         &dev_attr_name.attr,
 115         &dev_attr_active_count.attr,
 116         &dev_attr_event_count.attr,
 117         &dev_attr_wakeup_count.attr,
 118         &dev_attr_expire_count.attr,
 119         &dev_attr_active_time_ms.attr,
 120         &dev_attr_total_time_ms.attr,
 121         &dev_attr_max_time_ms.attr,
 122         &dev_attr_last_change_ms.attr,
 123         &dev_attr_prevent_suspend_time_ms.attr,
 124         NULL,
 125 };
 126 ATTRIBUTE_GROUPS(wakeup_source);
 127
 128 static void device_create_release(struct device *dev)
 129 {
 130         kfree(dev);
 131 }
 132
 133 static struct device *wakeup_source_device_create(struct device *parent,
 134                                                   struct wakeup_source *ws)
 135 {
 136         struct device *dev = NULL;
 137         int retval = -ENODEV;
 138
 139         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 140         if (!dev) {
 141                 retval = -ENOMEM;
 142                 goto error;
 143         }
 144
 145         device_initialize(dev);
 146         dev->devt = MKDEV(0, 0);
 147         dev->class = wakeup_class;
 148         dev->parent = parent;
 149         dev->groups = wakeup_source_groups;
 150         dev->release = device_create_release;
 151         dev_set_drvdata(dev, ws);
 152         device_set_pm_not_required(dev);
 153
 154         retval = kobject_set_name(&dev->kobj, "wakeup%d", ws->id);
 155         if (retval)
 156                 goto error;
 157
 158         retval = device_add(dev);
 159         if (retval)
 160                 goto error;
 161
 162         return dev;
 163
 164 error:
 165         put_device(dev);
 166         return ERR_PTR(retval);
 167 }
 168
 169 /**
 170  * wakeup_source_sysfs_add - Add wakeup_source attributes to sysfs.
 171  * @parent: Device given wakeup source is associated with (or NULL if virtual).
 172  * @ws: Wakeup source to be added in sysfs.
 173  */
 174 int wakeup_source_sysfs_add(struct device *parent, struct wakeup_source *ws)
 175 {
 176         struct device *dev;
 177
 178         dev = wakeup_source_device_create(parent, ws);
 179         if (IS_ERR(dev))
 180                 return PTR_ERR(dev);
 181         ws->dev = dev;
 182
 183         return 0;
 184 }
 185
 186 /**
 187  * pm_wakeup_source_sysfs_add - Add wakeup_source attributes to sysfs
 188  * for a device if they're missing.
 189  * @parent: Device given wakeup source is associated with
 190  */
 191 int pm_wakeup_source_sysfs_add(struct device *parent)
 192 {
 193         if (!parent->power.wakeup || parent->power.wakeup->dev)
 194                 return 0;
 195
 196         return wakeup_source_sysfs_add(parent, parent->power.wakeup);
 197 }
 198
 199 /**
 200  * wakeup_source_sysfs_remove - Remove wakeup_source attributes from sysfs.
 201  * @ws: Wakeup source to be removed from sysfs.
 202  */
 203 void wakeup_source_sysfs_remove(struct wakeup_source *ws)
 204 {
 205         device_unregister(ws->dev);
 206 }
 207
 208 static int __init wakeup_sources_sysfs_init(void)
 209 {
 210         wakeup_class = class_create(THIS_MODULE, "wakeup");
 211
 212         return PTR_ERR_OR_ZERO(wakeup_class);
 213 }
 214 postcore_initcall(wakeup_sources_sysfs_init);