thermal_trip.c

 1// SPDX-License-Identifier: GPL-2.0
 2/*
 3 *  Copyright (C) 2008 Intel Corp
 4 *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
 5 *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
 6 *  Copyright 2022 Linaro Limited
 7 *
 8 * Thermal trips handling
 9 */
10#include "thermal_core.h"
11
12static const char *trip_type_names[] = {
13	[THERMAL_TRIP_ACTIVE] = "active",
14	[THERMAL_TRIP_PASSIVE] = "passive",
15	[THERMAL_TRIP_HOT] = "hot",
16	[THERMAL_TRIP_CRITICAL] = "critical",
17};
18
19const char *thermal_trip_type_name(enum thermal_trip_type trip_type)
20{
21	if (trip_type < THERMAL_TRIP_ACTIVE || trip_type > THERMAL_TRIP_CRITICAL)
22		return "unknown";
23
24	return trip_type_names[trip_type];
25}
26
27int for_each_thermal_trip(struct thermal_zone_device *tz,
28			  int (*cb)(struct thermal_trip *, void *),
29			  void *data)
30{
31	struct thermal_trip_desc *td;
32	int ret;
33
34	for_each_trip_desc(tz, td) {
35		ret = cb(&td->trip, data);
36		if (ret)
37			return ret;
38	}
39
40	return 0;
41}
42EXPORT_SYMBOL_GPL(for_each_thermal_trip);
43
44int thermal_zone_for_each_trip(struct thermal_zone_device *tz,
45			       int (*cb)(struct thermal_trip *, void *),
46			       void *data)
47{
48	guard(thermal_zone)(tz);
49
50	return for_each_thermal_trip(tz, cb, data);
51}
52EXPORT_SYMBOL_GPL(thermal_zone_for_each_trip);
53
54void thermal_zone_set_trips(struct thermal_zone_device *tz, int low, int high)
55{
56	int ret;
57
58	lockdep_assert_held(&tz->lock);
59
60	if (!tz->ops.set_trips)
61		return;
62
63	/* No need to change trip points */
64	if (tz->prev_low_trip == low && tz->prev_high_trip == high)
65		return;
66
67	tz->prev_low_trip = low;
68	tz->prev_high_trip = high;
69
70	dev_dbg(&tz->device,
71		"new temperature boundaries: %d < x < %d\n", low, high);
72
73	/*
74	 * Set a temperature window. When this window is left the driver
75	 * must inform the thermal core via thermal_zone_device_update.
76	 */
77	ret = tz->ops.set_trips(tz, low, high);
78	if (ret)
79		dev_err(&tz->device, "Failed to set trips: %d\n", ret);
80}
81
82int thermal_zone_trip_id(const struct thermal_zone_device *tz,
83			 const struct thermal_trip *trip)
84{
85	/*
86	 * Assume the trip to be located within the bounds of the thermal
87	 * zone's trips[] table.
88	 */
89	return trip_to_trip_desc(trip) - tz->trips;
90}