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1What: /sys/class/thermal/thermal_zoneX/type
2Description:
3 Strings which represent the thermal zone type.
4 This is given by thermal zone driver as part of registration.
5 E.g: "acpitz" indicates it's an ACPI thermal device.
6 In order to keep it consistent with hwmon sys attribute; this
7 should be a short, lowercase string, not containing spaces nor
8 dashes.
9
10 RO, Required
11
12What: /sys/class/thermal/thermal_zoneX/temp
13Description:
14 Current temperature as reported by thermal zone (sensor).
15
16 Unit: millidegree Celsius
17
18 RO, Required
19
20What: /sys/class/thermal/thermal_zoneX/mode
21Description:
22 One of the predefined values in [enabled, disabled].
23 This file gives information about the algorithm that is
24 currently managing the thermal zone. It can be either default
25 kernel based algorithm or user space application.
26
27 enabled
28 enable Kernel Thermal management.
29 disabled
30 Preventing kernel thermal zone driver actions upon
31 trip points so that user application can take full
32 charge of the thermal management.
33
34 RW, Optional
35
36What: /sys/class/thermal/thermal_zoneX/policy
37Description:
38 One of the various thermal governors used for a particular zone.
39
40 RW, Required
41
42What: /sys/class/thermal/thermal_zoneX/available_policies
43Description:
44 Available thermal governors which can be used for a
45 particular zone.
46
47 RO, Required
48
49What: /sys/class/thermal/thermal_zoneX/trip_point_Y_temp
50Description:
51 The temperature above which trip point will be fired.
52
53 Unit: millidegree Celsius
54
55 RO, Optional
56
57What: /sys/class/thermal/thermal_zoneX/trip_point_Y_type
58Description:
59 Strings which indicate the type of the trip point.
60
61 E.g. it can be one of critical, hot, passive, `active[0-*]`
62 for ACPI thermal zone.
63
64 RO, Optional
65
66What: /sys/class/thermal/thermal_zoneX/trip_point_Y_hyst
67Description:
68 The hysteresis value for a trip point, represented as an
69 integer.
70
71 Unit: Celsius
72
73 RW, Optional
74
75What: /sys/class/thermal/thermal_zoneX/cdevY
76Description:
77 Sysfs link to the thermal cooling device node where the sys I/F
78 for cooling device throttling control represents.
79
80 RO, Optional
81
82What: /sys/class/thermal/thermal_zoneX/cdevY_trip_point
83Description:
84 The trip point in this thermal zone which `cdev[0-*]` is
85 associated with; -1 means the cooling device is not
86 associated with any trip point.
87
88 RO, Optional
89
90What: /sys/class/thermal/thermal_zoneX/cdevY_weight
91Description:
92 The influence of `cdev[0-*]` in this thermal zone. This value
93 is relative to the rest of cooling devices in the thermal
94 zone. For example, if a cooling device has a weight double
95 than that of other, it's twice as effective in cooling the
96 thermal zone.
97
98 RW, Optional
99
100What: /sys/class/thermal/thermal_zoneX/emul_temp
101Description:
102 Interface to set the emulated temperature method in thermal zone
103 (sensor). After setting this temperature, the thermal zone may
104 pass this temperature to platform emulation function if
105 registered or cache it locally. This is useful in debugging
106 different temperature threshold and its associated cooling
107 action. This is write only node and writing 0 on this node
108 should disable emulation.
109
110 Unit: millidegree Celsius
111
112 WO, Optional
113
114 WARNING:
115 Be careful while enabling this option on production systems,
116 because userland can easily disable the thermal policy by simply
117 flooding this sysfs node with low temperature values.
118
119
120What: /sys/class/thermal/thermal_zoneX/k_d
121Description:
122 The derivative term of the power allocator governor's PID
123 controller. For more information see
124 Documentation/driver-api/thermal/power_allocator.rst
125
126 RW, Optional
127
128What: /sys/class/thermal/thermal_zoneX/k_i
129Description:
130 The integral term of the power allocator governor's PID
131 controller. This term allows the PID controller to compensate
132 for long term drift. For more information see
133 Documentation/driver-api/thermal/power_allocator.rst
134
135 RW, Optional
136
137What: /sys/class/thermal/thermal_zoneX/k_po
138Description:
139 The proportional term of the power allocator governor's PID
140 controller during temperature overshoot. Temperature overshoot
141 is when the current temperature is above the "desired
142 temperature" trip point. For more information see
143 Documentation/driver-api/thermal/power_allocator.rst
144
145 RW, Optional
146
147What: /sys/class/thermal/thermal_zoneX/k_pu
148Description:
149 The proportional term of the power allocator governor's PID
150 controller during temperature undershoot. Temperature undershoot
151 is when the current temperature is below the "desired
152 temperature" trip point. For more information see
153 Documentation/driver-api/thermal/power_allocator.rst
154
155 RW, Optional
156
157What: /sys/class/thermal/thermal_zoneX/integral_cutoff
158Description:
159 Temperature offset from the desired temperature trip point
160 above which the integral term of the power allocator
161 governor's PID controller starts accumulating errors. For
162 example, if integral_cutoff is 0, then the integral term only
163 accumulates error when temperature is above the desired
164 temperature trip point. For more information see
165 Documentation/driver-api/thermal/power_allocator.rst
166
167 Unit: millidegree Celsius
168
169 RW, Optional
170
171What: /sys/class/thermal/thermal_zoneX/slope
172Description:
173 The slope constant used in a linear extrapolation model
174 to determine a hotspot temperature based off the sensor's
175 raw readings. It is up to the device driver to determine
176 the usage of these values.
177
178 RW, Optional
179
180What: /sys/class/thermal/thermal_zoneX/offset
181Description:
182 The offset constant used in a linear extrapolation model
183 to determine a hotspot temperature based off the sensor's
184 raw readings. It is up to the device driver to determine
185 the usage of these values.
186
187 RW, Optional
188
189What: /sys/class/thermal/thermal_zoneX/sustainable_power
190Description:
191 An estimate of the sustained power that can be dissipated by
192 the thermal zone. Used by the power allocator governor. For
193 more information see
194 Documentation/driver-api/thermal/power_allocator.rst
195
196 Unit: milliwatts
197
198 RW, Optional
199
200What: /sys/class/thermal/cooling_deviceX/type
201Description:
202 String which represents the type of device, e.g:
203
204 - for generic ACPI: should be "Fan", "Processor" or "LCD"
205 - for memory controller device on intel_menlow platform:
206 should be "Memory controller".
207
208 RO, Required
209
210What: /sys/class/thermal/cooling_deviceX/max_state
211Description:
212 The maximum permissible cooling state of this cooling device.
213
214 RO, Required
215
216What: /sys/class/thermal/cooling_deviceX/cur_state
217Description:
218 The current cooling state of this cooling device.
219 The value can any integer numbers between 0 and max_state:
220
221 - cur_state == 0 means no cooling
222 - cur_state == max_state means the maximum cooling.
223
224 RW, Required
225
226What: /sys/class/thermal/cooling_deviceX/stats/reset
227Description:
228 Writing any value resets the cooling device's statistics.
229
230 WO, Required
231
232What: /sys/class/thermal/cooling_deviceX/stats/time_in_state_ms:
233Description:
234 The amount of time spent by the cooling device in various
235 cooling states. The output will have "<state> <time>" pair
236 in each line, which will mean this cooling device spent <time>
237 msec of time at <state>.
238
239 Output will have one line for each of the supported states.
240
241 RO, Required
242
243What: /sys/class/thermal/cooling_deviceX/stats/total_trans
244Description:
245 A single positive value showing the total number of times
246 the state of a cooling device is changed.
247
248 RO, Required
249
250What: /sys/class/thermal/cooling_deviceX/stats/trans_table
251Description:
252 This gives fine grained information about all the cooling state
253 transitions. The cat output here is a two dimensional matrix,
254 where an entry <i,j> (row i, column j) represents the number
255 of transitions from State_i to State_j. If the transition
256 table is bigger than PAGE_SIZE, reading this will return
257 an -EFBIG error.
258
259 RO, Required