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
12 static 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
thermal_trip_type_name(enum thermal_trip_type trip_type)19 const 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
for_each_thermal_trip(struct thermal_zone_device * tz,int (* cb)(struct thermal_trip *,void *),void * data)27 int 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 }
42 EXPORT_SYMBOL_GPL(for_each_thermal_trip);
43
thermal_zone_for_each_trip(struct thermal_zone_device * tz,int (* cb)(struct thermal_trip *,void *),void * data)44 int thermal_zone_for_each_trip(struct thermal_zone_device *tz,
45 int (*cb)(struct thermal_trip *, void *),
46 void *data)
47 {
48 int ret;
49
50 mutex_lock(&tz->lock);
51 ret = for_each_thermal_trip(tz, cb, data);
52 mutex_unlock(&tz->lock);
53
54 return ret;
55 }
56 EXPORT_SYMBOL_GPL(thermal_zone_for_each_trip);
57
thermal_zone_set_trips(struct thermal_zone_device * tz,int low,int high)58 void thermal_zone_set_trips(struct thermal_zone_device *tz, int low, int high)
59 {
60 int ret;
61
62 lockdep_assert_held(&tz->lock);
63
64 if (!tz->ops.set_trips)
65 return;
66
67 /* No need to change trip points */
68 if (tz->prev_low_trip == low && tz->prev_high_trip == high)
69 return;
70
71 tz->prev_low_trip = low;
72 tz->prev_high_trip = high;
73
74 dev_dbg(&tz->device,
75 "new temperature boundaries: %d < x < %d\n", low, high);
76
77 /*
78 * Set a temperature window. When this window is left the driver
79 * must inform the thermal core via thermal_zone_device_update.
80 */
81 ret = tz->ops.set_trips(tz, low, high);
82 if (ret)
83 dev_err(&tz->device, "Failed to set trips: %d\n", ret);
84 }
85
thermal_zone_trip_id(const struct thermal_zone_device * tz,const struct thermal_trip * trip)86 int thermal_zone_trip_id(const struct thermal_zone_device *tz,
87 const struct thermal_trip *trip)
88 {
89 /*
90 * Assume the trip to be located within the bounds of the thermal
91 * zone's trips[] table.
92 */
93 return trip_to_trip_desc(trip) - tz->trips;
94 }
95
thermal_zone_set_trip_hyst(struct thermal_zone_device * tz,struct thermal_trip * trip,int hyst)96 void thermal_zone_set_trip_hyst(struct thermal_zone_device *tz,
97 struct thermal_trip *trip, int hyst)
98 {
99 WRITE_ONCE(trip->hysteresis, hyst);
100 thermal_notify_tz_trip_change(tz, trip);
101 }
102
thermal_zone_set_trip_temp(struct thermal_zone_device * tz,struct thermal_trip * trip,int temp)103 void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
104 struct thermal_trip *trip, int temp)
105 {
106 if (trip->temperature == temp)
107 return;
108
109 WRITE_ONCE(trip->temperature, temp);
110 thermal_notify_tz_trip_change(tz, trip);
111
112 if (temp == THERMAL_TEMP_INVALID) {
113 struct thermal_trip_desc *td = trip_to_trip_desc(trip);
114
115 if (tz->temperature >= td->threshold) {
116 /*
117 * The trip has been crossed on the way up, so some
118 * adjustments are needed to compensate for the lack
119 * of it going forward.
120 */
121 if (trip->type == THERMAL_TRIP_PASSIVE) {
122 tz->passive--;
123 WARN_ON_ONCE(tz->passive < 0);
124 }
125 thermal_zone_trip_down(tz, trip);
126 }
127 /*
128 * Invalidate the threshold to avoid triggering a spurious
129 * trip crossing notification when the trip becomes valid.
130 */
131 td->threshold = INT_MAX;
132 }
133 }
134 EXPORT_SYMBOL_GPL(thermal_zone_set_trip_temp);
135