1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * user_space.c - A simple user space Thermal events notifier
4 *
5 * Copyright (C) 2012 Intel Corp
6 * Copyright (C) 2012 Durgadoss R <durgadoss.r@intel.com>
7 *
8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 *
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 */
12
13#include <linux/slab.h>
14#include <linux/thermal.h>
15
16#include "thermal_core.h"
17
18static int user_space_bind(struct thermal_zone_device *tz)
19{
20 pr_info_once("Consider using thermal netlink events interface\n");
21
22 return 0;
23}
24
25/**
26 * notify_user_space - Notifies user space about thermal events
27 * @tz: thermal_zone_device
28 * @trip: trip point
29 *
30 * This function notifies the user space through UEvents.
31 */
32static int notify_user_space(struct thermal_zone_device *tz,
33 const struct thermal_trip *trip)
34{
35 char *thermal_prop[5];
36 int i;
37
38 lockdep_assert_held(&tz->lock);
39
40 thermal_prop[0] = kasprintf(GFP_KERNEL, fmt: "NAME=%s", tz->type);
41 thermal_prop[1] = kasprintf(GFP_KERNEL, fmt: "TEMP=%d", tz->temperature);
42 thermal_prop[2] = kasprintf(GFP_KERNEL, fmt: "TRIP=%d",
43 thermal_zone_trip_id(tz, trip));
44 thermal_prop[3] = kasprintf(GFP_KERNEL, fmt: "EVENT=%d", tz->notify_event);
45 thermal_prop[4] = NULL;
46 kobject_uevent_env(kobj: &tz->device.kobj, action: KOBJ_CHANGE, envp: thermal_prop);
47 for (i = 0; i < 4; ++i)
48 kfree(objp: thermal_prop[i]);
49
50 return 0;
51}
52
53static struct thermal_governor thermal_gov_user_space = {
54 .name = "user_space",
55 .throttle = notify_user_space,
56 .bind_to_tz = user_space_bind,
57};
58THERMAL_GOVERNOR_DECLARE(thermal_gov_user_space);
59

source code of linux/drivers/thermal/gov_user_space.c