base/power/wakeup_stats.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * Wakeup statistics in sysfs
0004  *
0005  * Copyright (c) 2019 Linux Foundation
0006  * Copyright (c) 2019 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
0007  * Copyright (c) 2019 Google Inc.
0008  */
0009
0010 #include <linux/device.h>
0011 #include <linux/idr.h>
0012 #include <linux/init.h>
0013 #include <linux/kdev_t.h>
0014 #include <linux/kernel.h>
0015 #include <linux/kobject.h>
0016 #include <linux/slab.h>
0017 #include <linux/timekeeping.h>
0018
0019 #include "power.h"
0020
0021 static struct class *wakeup_class;
0022
0023 #define wakeup_attr(_name)                      \
0024 static ssize_t _name##_show(struct device *dev,             \
0025                 struct device_attribute *attr, char *buf)   \
0026 {                                   \
0027     struct wakeup_source *ws = dev_get_drvdata(dev);        \
0028                                     \
0029     return sysfs_emit(buf, "%lu\n", ws->_name);         \
0030 }                                   \
0031 static DEVICE_ATTR_RO(_name)
0032
0033 wakeup_attr(active_count);
0034 wakeup_attr(event_count);
0035 wakeup_attr(wakeup_count);
0036 wakeup_attr(expire_count);
0037
0038 static ssize_t active_time_ms_show(struct device *dev,
0039                    struct device_attribute *attr, char *buf)
0040 {
0041     struct wakeup_source *ws = dev_get_drvdata(dev);
0042     ktime_t active_time =
0043         ws->active ? ktime_sub(ktime_get(), ws->last_time) : 0;
0044
0045     return sysfs_emit(buf, "%lld\n", ktime_to_ms(active_time));
0046 }
0047 static DEVICE_ATTR_RO(active_time_ms);
0048
0049 static ssize_t total_time_ms_show(struct device *dev,
0050                   struct device_attribute *attr, char *buf)
0051 {
0052     struct wakeup_source *ws = dev_get_drvdata(dev);
0053     ktime_t active_time;
0054     ktime_t total_time = ws->total_time;
0055
0056     if (ws->active) {
0057         active_time = ktime_sub(ktime_get(), ws->last_time);
0058         total_time = ktime_add(total_time, active_time);
0059     }
0060
0061     return sysfs_emit(buf, "%lld\n", ktime_to_ms(total_time));
0062 }
0063 static DEVICE_ATTR_RO(total_time_ms);
0064
0065 static ssize_t max_time_ms_show(struct device *dev,
0066                 struct device_attribute *attr, char *buf)
0067 {
0068     struct wakeup_source *ws = dev_get_drvdata(dev);
0069     ktime_t active_time;
0070     ktime_t max_time = ws->max_time;
0071
0072     if (ws->active) {
0073         active_time = ktime_sub(ktime_get(), ws->last_time);
0074         if (active_time > max_time)
0075             max_time = active_time;
0076     }
0077
0078     return sysfs_emit(buf, "%lld\n", ktime_to_ms(max_time));
0079 }
0080 static DEVICE_ATTR_RO(max_time_ms);
0081
0082 static ssize_t last_change_ms_show(struct device *dev,
0083                    struct device_attribute *attr, char *buf)
0084 {
0085     struct wakeup_source *ws = dev_get_drvdata(dev);
0086
0087     return sysfs_emit(buf, "%lld\n", ktime_to_ms(ws->last_time));
0088 }
0089 static DEVICE_ATTR_RO(last_change_ms);
0090
0091 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
0092              char *buf)
0093 {
0094     struct wakeup_source *ws = dev_get_drvdata(dev);
0095
0096     return sysfs_emit(buf, "%s\n", ws->name);
0097 }
0098 static DEVICE_ATTR_RO(name);
0099
0100 static ssize_t prevent_suspend_time_ms_show(struct device *dev,
0101                         struct device_attribute *attr,
0102                         char *buf)
0103 {
0104     struct wakeup_source *ws = dev_get_drvdata(dev);
0105     ktime_t prevent_sleep_time = ws->prevent_sleep_time;
0106
0107     if (ws->active && ws->autosleep_enabled) {
0108         prevent_sleep_time = ktime_add(prevent_sleep_time,
0109             ktime_sub(ktime_get(), ws->start_prevent_time));
0110     }
0111
0112     return sysfs_emit(buf, "%lld\n", ktime_to_ms(prevent_sleep_time));
0113 }
0114 static DEVICE_ATTR_RO(prevent_suspend_time_ms);
0115
0116 static struct attribute *wakeup_source_attrs[] = {
0117     &dev_attr_name.attr,
0118     &dev_attr_active_count.attr,
0119     &dev_attr_event_count.attr,
0120     &dev_attr_wakeup_count.attr,
0121     &dev_attr_expire_count.attr,
0122     &dev_attr_active_time_ms.attr,
0123     &dev_attr_total_time_ms.attr,
0124     &dev_attr_max_time_ms.attr,
0125     &dev_attr_last_change_ms.attr,
0126     &dev_attr_prevent_suspend_time_ms.attr,
0127     NULL,
0128 };
0129 ATTRIBUTE_GROUPS(wakeup_source);
0130
0131 static void device_create_release(struct device *dev)
0132 {
0133     kfree(dev);
0134 }
0135
0136 static struct device *wakeup_source_device_create(struct device *parent,
0137                           struct wakeup_source *ws)
0138 {
0139     struct device *dev = NULL;
0140     int retval;
0141
0142     dev = kzalloc(sizeof(*dev), GFP_KERNEL);
0143     if (!dev) {
0144         retval = -ENOMEM;
0145         goto error;
0146     }
0147
0148     device_initialize(dev);
0149     dev->devt = MKDEV(0, 0);
0150     dev->class = wakeup_class;
0151     dev->parent = parent;
0152     dev->groups = wakeup_source_groups;
0153     dev->release = device_create_release;
0154     dev_set_drvdata(dev, ws);
0155     device_set_pm_not_required(dev);
0156
0157     retval = dev_set_name(dev, "wakeup%d", ws->id);
0158     if (retval)
0159         goto error;
0160
0161     retval = device_add(dev);
0162     if (retval)
0163         goto error;
0164
0165     return dev;
0166
0167 error:
0168     put_device(dev);
0169     return ERR_PTR(retval);
0170 }
0171
0172 /**
0173  * wakeup_source_sysfs_add - Add wakeup_source attributes to sysfs.
0174  * @parent: Device given wakeup source is associated with (or NULL if virtual).
0175  * @ws: Wakeup source to be added in sysfs.
0176  */
0177 int wakeup_source_sysfs_add(struct device *parent, struct wakeup_source *ws)
0178 {
0179     struct device *dev;
0180
0181     dev = wakeup_source_device_create(parent, ws);
0182     if (IS_ERR(dev))
0183         return PTR_ERR(dev);
0184     ws->dev = dev;
0185
0186     return 0;
0187 }
0188
0189 /**
0190  * pm_wakeup_source_sysfs_add - Add wakeup_source attributes to sysfs
0191  * for a device if they're missing.
0192  * @parent: Device given wakeup source is associated with
0193  */
0194 int pm_wakeup_source_sysfs_add(struct device *parent)
0195 {
0196     if (!parent->power.wakeup || parent->power.wakeup->dev)
0197         return 0;
0198
0199     return wakeup_source_sysfs_add(parent, parent->power.wakeup);
0200 }
0201
0202 /**
0203  * wakeup_source_sysfs_remove - Remove wakeup_source attributes from sysfs.
0204  * @ws: Wakeup source to be removed from sysfs.
0205  */
0206 void wakeup_source_sysfs_remove(struct wakeup_source *ws)
0207 {
0208     device_unregister(ws->dev);
0209 }
0210
0211 static int __init wakeup_sources_sysfs_init(void)
0212 {
0213     wakeup_class = class_create(THIS_MODULE, "wakeup");
0214
0215     return PTR_ERR_OR_ZERO(wakeup_class);
0216 }
0217 postcore_initcall(wakeup_sources_sysfs_init);