1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25#include <linux/thermal.h>
26
27#include "thermal_core.h"
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49static unsigned long get_target_state(struct thermal_instance *instance,
50 enum thermal_trend trend, bool throttle)
51{
52 struct thermal_cooling_device *cdev = instance->cdev;
53 unsigned long cur_state;
54
55 cdev->ops->get_cur_state(cdev, &cur_state);
56
57 switch (trend) {
58 case THERMAL_TREND_RAISING:
59 if (throttle) {
60 cur_state = cur_state < instance->upper ?
61 (cur_state + 1) : instance->upper;
62 if (cur_state < instance->lower)
63 cur_state = instance->lower;
64 }
65 break;
66 case THERMAL_TREND_RAISE_FULL:
67 if (throttle)
68 cur_state = instance->upper;
69 break;
70 case THERMAL_TREND_DROPPING:
71 if (cur_state == instance->lower) {
72 if (!throttle)
73 cur_state = -1;
74 } else {
75 cur_state -= 1;
76 if (cur_state > instance->upper)
77 cur_state = instance->upper;
78 }
79 break;
80 case THERMAL_TREND_DROP_FULL:
81 if (cur_state == instance->lower) {
82 if (!throttle)
83 cur_state = -1;
84 } else
85 cur_state = instance->lower;
86 break;
87 default:
88 break;
89 }
90
91 return cur_state;
92}
93
94static void update_passive_instance(struct thermal_zone_device *tz,
95 enum thermal_trip_type type, int value)
96{
97
98
99
100
101 if (type == THERMAL_TRIP_PASSIVE || type == THERMAL_TRIPS_NONE)
102 tz->passive += value;
103}
104
105static void thermal_zone_trip_update(struct thermal_zone_device *tz, int trip)
106{
107 long trip_temp;
108 enum thermal_trip_type trip_type;
109 enum thermal_trend trend;
110 struct thermal_instance *instance;
111 bool throttle = false;
112 int old_target;
113
114 if (trip == THERMAL_TRIPS_NONE) {
115 trip_temp = tz->forced_passive;
116 trip_type = THERMAL_TRIPS_NONE;
117 } else {
118 tz->ops->get_trip_temp(tz, trip, &trip_temp);
119 tz->ops->get_trip_type(tz, trip, &trip_type);
120 }
121
122 trend = get_tz_trend(tz, trip);
123
124 if (tz->temperature >= trip_temp)
125 throttle = true;
126
127 mutex_lock(&tz->lock);
128
129 list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
130 if (instance->trip != trip)
131 continue;
132
133 old_target = instance->target;
134 instance->target = get_target_state(instance, trend, throttle);
135
136
137 if (old_target == THERMAL_NO_TARGET &&
138 instance->target != THERMAL_NO_TARGET)
139 update_passive_instance(tz, trip_type, 1);
140
141 else if (old_target != THERMAL_NO_TARGET &&
142 instance->target == THERMAL_NO_TARGET)
143 update_passive_instance(tz, trip_type, -1);
144
145
146 instance->cdev->updated = false;
147 }
148
149 mutex_unlock(&tz->lock);
150}
151
152
153
154
155
156
157
158
159
160
161
162
163
164static int step_wise_throttle(struct thermal_zone_device *tz, int trip)
165{
166 struct thermal_instance *instance;
167
168 thermal_zone_trip_update(tz, trip);
169
170 if (tz->forced_passive)
171 thermal_zone_trip_update(tz, THERMAL_TRIPS_NONE);
172
173 mutex_lock(&tz->lock);
174
175 list_for_each_entry(instance, &tz->thermal_instances, tz_node)
176 thermal_cdev_update(instance->cdev);
177
178 mutex_unlock(&tz->lock);
179
180 return 0;
181}
182
183static struct thermal_governor thermal_gov_step_wise = {
184 .name = "step_wise",
185 .throttle = step_wise_throttle,
186};
187
188int thermal_gov_step_wise_register(void)
189{
190 return thermal_register_governor(&thermal_gov_step_wise);
191}
192
193void thermal_gov_step_wise_unregister(void)
194{
195 thermal_unregister_governor(&thermal_gov_step_wise);
196}
197