1 What: /sys/power/ 1 What: /sys/power/
2 Date: August 2006 2 Date: August 2006
3 Contact: Rafael J. Wysocki <rjw@rjwysock 3 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
4 Description: 4 Description:
5 The /sys/power directory will 5 The /sys/power directory will contain files that will
6 provide a unified interface to 6 provide a unified interface to the power management
7 subsystem. 7 subsystem.
8 8
9 What: /sys/power/state 9 What: /sys/power/state
10 Date: November 2016 10 Date: November 2016
11 Contact: Rafael J. Wysocki <rjw@rjwysock 11 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
12 Description: 12 Description:
13 The /sys/power/state file cont 13 The /sys/power/state file controls system sleep states.
14 Reading from this file returns 14 Reading from this file returns the available sleep state
15 labels, which may be "mem" (su 15 labels, which may be "mem" (suspend), "standby" (power-on
16 suspend), "freeze" (suspend-to 16 suspend), "freeze" (suspend-to-idle) and "disk" (hibernation).
17 17
18 Writing one of the above strin 18 Writing one of the above strings to this file causes the system
19 to transition into the corresp 19 to transition into the corresponding state, if available.
20 20
21 See Documentation/admin-guide/ 21 See Documentation/admin-guide/pm/sleep-states.rst for more
22 information. 22 information.
23 23
24 What: /sys/power/mem_sleep 24 What: /sys/power/mem_sleep
25 Date: November 2016 25 Date: November 2016
26 Contact: Rafael J. Wysocki <rjw@rjwysock 26 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
27 Description: 27 Description:
28 The /sys/power/mem_sleep file 28 The /sys/power/mem_sleep file controls the operating mode of
29 system suspend. Reading from 29 system suspend. Reading from it returns the available modes
30 as "s2idle" (always present), 30 as "s2idle" (always present), "shallow" and "deep" (present if
31 supported). The mode that wil 31 supported). The mode that will be used on subsequent attempts
32 to suspend the system (by writ 32 to suspend the system (by writing "mem" to the /sys/power/state
33 file described above) is enclo 33 file described above) is enclosed in square brackets.
34 34
35 Writing one of the above strin 35 Writing one of the above strings to this file causes the mode
36 represented by it to be used o 36 represented by it to be used on subsequent attempts to suspend
37 the system. 37 the system.
38 38
39 See Documentation/admin-guide/ 39 See Documentation/admin-guide/pm/sleep-states.rst for more
40 information. 40 information.
41 41
42 What: /sys/power/disk 42 What: /sys/power/disk
43 Date: September 2006 43 Date: September 2006
44 Contact: Rafael J. Wysocki <rjw@rjwysock 44 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
45 Description: 45 Description:
46 The /sys/power/disk file contr 46 The /sys/power/disk file controls the operating mode of the
47 suspend-to-disk mechanism. Re 47 suspend-to-disk mechanism. Reading from this file returns
48 the name of the method by whic 48 the name of the method by which the system will be put to
49 sleep on the next suspend. Th 49 sleep on the next suspend. There are four methods supported:
50 50
51 'firmware' - means that the me 51 'firmware' - means that the memory image will be saved to disk
52 by some firmware, in which cas 52 by some firmware, in which case we also assume that the
53 firmware will handle the syste 53 firmware will handle the system suspend.
54 54
55 'platform' - the memory image 55 'platform' - the memory image will be saved by the kernel and
56 the system will be put to slee 56 the system will be put to sleep by the platform driver (e.g.
57 ACPI or other PM registers). 57 ACPI or other PM registers).
58 58
59 'shutdown' - the memory image 59 'shutdown' - the memory image will be saved by the kernel and
60 the system will be powered off 60 the system will be powered off.
61 61
62 'reboot' - the memory image wi 62 'reboot' - the memory image will be saved by the kernel and
63 the system will be rebooted. 63 the system will be rebooted.
64 64
65 Additionally, /sys/power/disk 65 Additionally, /sys/power/disk can be used to turn on one of the
66 two testing modes of the suspe 66 two testing modes of the suspend-to-disk mechanism: 'testproc'
67 or 'test'. If the suspend-to- 67 or 'test'. If the suspend-to-disk mechanism is in the
68 'testproc' mode, writing 'disk 68 'testproc' mode, writing 'disk' to /sys/power/state will cause
69 the kernel to disable nonboot 69 the kernel to disable nonboot CPUs and freeze tasks, wait for 5
70 seconds, unfreeze tasks and en 70 seconds, unfreeze tasks and enable nonboot CPUs. If it is in
71 the 'test' mode, writing 'disk 71 the 'test' mode, writing 'disk' to /sys/power/state will cause
72 the kernel to disable nonboot 72 the kernel to disable nonboot CPUs and freeze tasks, shrink
73 memory, suspend devices, wait 73 memory, suspend devices, wait for 5 seconds, resume devices,
74 unfreeze tasks and enable nonb 74 unfreeze tasks and enable nonboot CPUs. Then, we are able to
75 look in the log messages and w 75 look in the log messages and work out, for example, which code
76 is being slow and which device 76 is being slow and which device drivers are misbehaving.
77 77
78 The suspend-to-disk method may 78 The suspend-to-disk method may be chosen by writing to this
79 file one of the accepted strin 79 file one of the accepted strings:
80 80
81 - 'firmware' 81 - 'firmware'
82 - 'platform' 82 - 'platform'
83 - 'shutdown' 83 - 'shutdown'
84 - 'reboot' 84 - 'reboot'
85 - 'testproc' 85 - 'testproc'
86 - 'test' 86 - 'test'
87 87
88 It will only change to 'firmwa 88 It will only change to 'firmware' or 'platform' if the system
89 supports that. 89 supports that.
90 90
91 What: /sys/power/image_size 91 What: /sys/power/image_size
92 Date: August 2006 92 Date: August 2006
93 Contact: Rafael J. Wysocki <rjw@rjwysock 93 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
94 Description: 94 Description:
95 The /sys/power/image_size file 95 The /sys/power/image_size file controls the size of the image
96 created by the suspend-to-disk 96 created by the suspend-to-disk mechanism. It can be written a
97 string representing a non-nega 97 string representing a non-negative integer that will be used
98 as an upper limit of the image 98 as an upper limit of the image size, in bytes. The kernel's
99 suspend-to-disk code will do i 99 suspend-to-disk code will do its best to ensure the image size
100 will not exceed this number. 100 will not exceed this number. However, if it turns out to be
101 impossible, the kernel will tr 101 impossible, the kernel will try to suspend anyway using the
102 smallest image possible. In p 102 smallest image possible. In particular, if "0" is written to
103 this file, the suspend image w 103 this file, the suspend image will be as small as possible.
104 104
105 Reading from this file will di 105 Reading from this file will display the current image size
106 limit, which is set to around 106 limit, which is set to around 2/5 of available RAM by default.
107 107
108 What: /sys/power/pm_trace 108 What: /sys/power/pm_trace
109 Date: August 2006 109 Date: August 2006
110 Contact: Rafael J. Wysocki <rjw@rjwysock 110 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
111 Description: 111 Description:
112 The /sys/power/pm_trace file c 112 The /sys/power/pm_trace file controls the code which saves the
113 last PM event point in the RTC 113 last PM event point in the RTC across reboots, so that you can
114 debug a machine that just hang 114 debug a machine that just hangs during suspend (or more
115 commonly, during resume). Nam 115 commonly, during resume). Namely, the RTC is only used to save
116 the last PM event point if thi 116 the last PM event point if this file contains '1'. Initially
117 it contains '0' which may be c 117 it contains '0' which may be changed to '1' by writing a
118 string representing a nonzero 118 string representing a nonzero integer into it.
119 119
120 To use this debugging feature 120 To use this debugging feature you should attempt to suspend
121 the machine, then reboot it an 121 the machine, then reboot it and run::
122 122
123 dmesg -s 1000000 | grep 'has 123 dmesg -s 1000000 | grep 'hash matches'
124 124
125 If you do not get any matches 125 If you do not get any matches (or they appear to be false
126 positives), it is possible tha 126 positives), it is possible that the last PM event point
127 referred to a device created b 127 referred to a device created by a loadable kernel module. In
128 this case cat /sys/power/pm_tr 128 this case cat /sys/power/pm_trace_dev_match (see below) after
129 your system is started up and 129 your system is started up and the kernel modules are loaded.
130 130
131 CAUTION: Using it will cause y 131 CAUTION: Using it will cause your machine's real-time (CMOS)
132 clock to be set to a random in 132 clock to be set to a random invalid time after a resume.
133 133
134 What; /sys/power/pm_trace_dev_match 134 What; /sys/power/pm_trace_dev_match
135 Date: October 2010 135 Date: October 2010
136 Contact: James Hogan <jhogan@kernel.org> 136 Contact: James Hogan <jhogan@kernel.org>
137 Description: 137 Description:
138 The /sys/power/pm_trace_dev_ma 138 The /sys/power/pm_trace_dev_match file contains the name of the
139 device associated with the las 139 device associated with the last PM event point saved in the RTC
140 across reboots when pm_trace h 140 across reboots when pm_trace has been used. More precisely it
141 contains the list of current d 141 contains the list of current devices (including those
142 registered by loadable kernel 142 registered by loadable kernel modules since boot) which match
143 the device hash in the RTC at 143 the device hash in the RTC at boot, with a newline after each
144 one. 144 one.
145 145
146 The advantage of this file ove 146 The advantage of this file over the hash matches printed to the
147 kernel log (see /sys/power/pm_ 147 kernel log (see /sys/power/pm_trace), is that it includes
148 devices created after boot by 148 devices created after boot by loadable kernel modules.
149 149
150 Due to the small hash size nec 150 Due to the small hash size necessary to fit in the RTC, it is
151 possible that more than one de 151 possible that more than one device matches the hash, in which
152 case further investigation is 152 case further investigation is required to determine which
153 device is causing the problem. 153 device is causing the problem. Note that genuine RTC clock
154 values (such as when pm_trace 154 values (such as when pm_trace has not been used), can still
155 match a device and output its !! 155 match a device and output it's name here.
156 156
157 What: /sys/power/pm_async 157 What: /sys/power/pm_async
158 Date: January 2009 158 Date: January 2009
159 Contact: Rafael J. Wysocki <rjw@rjwysock 159 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
160 Description: 160 Description:
161 The /sys/power/pm_async file c 161 The /sys/power/pm_async file controls the switch allowing the
162 user space to enable or disabl 162 user space to enable or disable asynchronous suspend and resume
163 of devices. If enabled, this 163 of devices. If enabled, this feature will cause some device
164 drivers' suspend and resume ca 164 drivers' suspend and resume callbacks to be executed in parallel
165 with each other and with the m 165 with each other and with the main suspend thread. It is enabled
166 if this file contains "1", whi 166 if this file contains "1", which is the default. It may be
167 disabled by writing "0" to thi 167 disabled by writing "0" to this file, in which case all devices
168 will be suspended and resumed 168 will be suspended and resumed synchronously.
169 169
170 What: /sys/power/wakeup_count 170 What: /sys/power/wakeup_count
171 Date: July 2010 171 Date: July 2010
172 Contact: Rafael J. Wysocki <rjw@rjwysock 172 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
173 Description: 173 Description:
174 The /sys/power/wakeup_count fi 174 The /sys/power/wakeup_count file allows user space to put the
175 system into a sleep state whil 175 system into a sleep state while taking into account the
176 concurrent arrival of wakeup e 176 concurrent arrival of wakeup events. Reading from it returns
177 the current number of register 177 the current number of registered wakeup events and it blocks if
178 some wakeup events are being p 178 some wakeup events are being processed at the time the file is
179 read from. Writing to it will 179 read from. Writing to it will only succeed if the current
180 number of wakeup events is equ 180 number of wakeup events is equal to the written value and, if
181 successful, will make the kern 181 successful, will make the kernel abort a subsequent transition
182 to a sleep state if any wakeup 182 to a sleep state if any wakeup events are reported after the
183 write has returned. 183 write has returned.
184 184
185 What: /sys/power/reserved_size 185 What: /sys/power/reserved_size
186 Date: May 2011 186 Date: May 2011
187 Contact: Rafael J. Wysocki <rjw@rjwysock 187 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
188 Description: 188 Description:
189 The /sys/power/reserved_size f 189 The /sys/power/reserved_size file allows user space to control
190 the amount of memory reserved 190 the amount of memory reserved for allocations made by device
191 drivers during the "device fre 191 drivers during the "device freeze" stage of hibernation. It can
192 be written a string representi 192 be written a string representing a non-negative integer that
193 will be used as the amount of 193 will be used as the amount of memory to reserve for allocations
194 made by device drivers' "freez 194 made by device drivers' "freeze" callbacks, in bytes.
195 195
196 Reading from this file will di 196 Reading from this file will display the current value, which is
197 set to 1 MB by default. 197 set to 1 MB by default.
198 198
199 What: /sys/power/autosleep 199 What: /sys/power/autosleep
200 Date: April 2012 200 Date: April 2012
201 Contact: Rafael J. Wysocki <rjw@rjwysock 201 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
202 Description: 202 Description:
203 The /sys/power/autosleep file 203 The /sys/power/autosleep file can be written one of the strings
204 returned by reads from /sys/po 204 returned by reads from /sys/power/state. If that happens, a
205 work item attempting to trigge 205 work item attempting to trigger a transition of the system to
206 the sleep state represented by 206 the sleep state represented by that string is queued up. This
207 attempt will only succeed if t 207 attempt will only succeed if there are no active wakeup sources
208 in the system at that time. A 208 in the system at that time. After every execution, regardless
209 of whether or not the attempt 209 of whether or not the attempt to put the system to sleep has
210 succeeded, the work item reque 210 succeeded, the work item requeues itself until user space
211 writes "off" to /sys/power/aut 211 writes "off" to /sys/power/autosleep.
212 212
213 Reading from this file causes 213 Reading from this file causes the last string successfully
214 written to it to be returned. 214 written to it to be returned.
215 215
216 What: /sys/power/wake_lock 216 What: /sys/power/wake_lock
217 Date: February 2012 217 Date: February 2012
218 Contact: Rafael J. Wysocki <rjw@rjwysock 218 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
219 Description: 219 Description:
220 The /sys/power/wake_lock file 220 The /sys/power/wake_lock file allows user space to create
221 wakeup source objects and acti 221 wakeup source objects and activate them on demand (if one of
222 those wakeup sources is active 222 those wakeup sources is active, reads from the
223 /sys/power/wakeup_count file b 223 /sys/power/wakeup_count file block or return false). When a
224 string without white space is 224 string without white space is written to /sys/power/wake_lock,
225 it will be assumed to represen 225 it will be assumed to represent a wakeup source name. If there
226 is a wakeup source object with 226 is a wakeup source object with that name, it will be activated
227 (unless active already). Othe 227 (unless active already). Otherwise, a new wakeup source object
228 will be registered, assigned t 228 will be registered, assigned the given name and activated.
229 If a string written to /sys/po 229 If a string written to /sys/power/wake_lock contains white
230 space, the part of the string 230 space, the part of the string preceding the white space will be
231 regarded as a wakeup source na 231 regarded as a wakeup source name and handled as descrived above.
232 The other part of the string w 232 The other part of the string will be regarded as a timeout (in
233 nanoseconds) such that the wak 233 nanoseconds) such that the wakeup source will be automatically
234 deactivated after it has expir 234 deactivated after it has expired. The timeout, if present, is
235 set regardless of the current 235 set regardless of the current state of the wakeup source object
236 in question. 236 in question.
237 237
238 Reads from this file return a 238 Reads from this file return a string consisting of the names of
239 wakeup sources created with th 239 wakeup sources created with the help of it that are active at
240 the moment, separated with spa 240 the moment, separated with spaces.
241 241
242 242
243 What: /sys/power/wake_unlock 243 What: /sys/power/wake_unlock
244 Date: February 2012 244 Date: February 2012
245 Contact: Rafael J. Wysocki <rjw@rjwysock 245 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
246 Description: 246 Description:
247 The /sys/power/wake_unlock fil 247 The /sys/power/wake_unlock file allows user space to deactivate
248 wakeup sources created with th 248 wakeup sources created with the help of /sys/power/wake_lock.
249 When a string is written to /s 249 When a string is written to /sys/power/wake_unlock, it will be
250 assumed to represent the name 250 assumed to represent the name of a wakeup source to deactivate.
251 251
252 If a wakeup source object of t 252 If a wakeup source object of that name exists and is active at
253 the moment, it will be deactiv 253 the moment, it will be deactivated.
254 254
255 Reads from this file return a 255 Reads from this file return a string consisting of the names of
256 wakeup sources created with th 256 wakeup sources created with the help of /sys/power/wake_lock
257 that are inactive at the momen 257 that are inactive at the moment, separated with spaces.
258 258
259 What: /sys/power/pm_print_times 259 What: /sys/power/pm_print_times
260 Date: May 2012 260 Date: May 2012
261 Contact: Sameer Nanda <snanda@chromium.o 261 Contact: Sameer Nanda <snanda@chromium.org>
262 Description: 262 Description:
263 The /sys/power/pm_print_times 263 The /sys/power/pm_print_times file allows user space to
264 control whether the time taken 264 control whether the time taken by devices to suspend and
265 resume is printed. These prin 265 resume is printed. These prints are useful for hunting down
266 devices that take too long to 266 devices that take too long to suspend or resume.
267 267
268 Writing a "1" enables this pri 268 Writing a "1" enables this printing while writing a "0"
269 disables it. The default valu 269 disables it. The default value is "0". Reading from this file
270 will display the current value 270 will display the current value.
271 271
272 What: /sys/power/pm_wakeup_irq 272 What: /sys/power/pm_wakeup_irq
273 Date: April 2015 273 Date: April 2015
274 Contact: Alexandra Yates <alexandra.yate 274 Contact: Alexandra Yates <alexandra.yates@linux.intel.org>
275 Description: 275 Description:
276 The /sys/power/pm_wakeup_irq f 276 The /sys/power/pm_wakeup_irq file reports to user space the IRQ
277 number of the first wakeup int 277 number of the first wakeup interrupt (that is, the first
278 interrupt from an IRQ line arm 278 interrupt from an IRQ line armed for system wakeup) seen by the
279 kernel during the most recent 279 kernel during the most recent system suspend/resume cycle.
280 280
281 This output is useful for syst 281 This output is useful for system wakeup diagnostics of spurious
282 wakeup interrupts. 282 wakeup interrupts.
283 283
284 What: /sys/power/pm_debug_messages 284 What: /sys/power/pm_debug_messages
285 Date: July 2017 285 Date: July 2017
286 Contact: Rafael J. Wysocki <rjw@rjwysock 286 Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
287 Description: 287 Description:
288 The /sys/power/pm_debug_messag 288 The /sys/power/pm_debug_messages file controls the printing
289 of debug messages from the sys 289 of debug messages from the system suspend/hiberbation
290 infrastructure to the kernel l 290 infrastructure to the kernel log.
291 291
292 Writing a "1" to this file ena 292 Writing a "1" to this file enables the debug messages and
293 writing a "0" (default) to it 293 writing a "0" (default) to it disables them. Reads from
294 this file return the current v 294 this file return the current value.
295 295
296 What: /sys/power/resume_offset 296 What: /sys/power/resume_offset
297 Date: April 2018 297 Date: April 2018
298 Contact: Mario Limonciello <mario.limonc 298 Contact: Mario Limonciello <mario.limonciello@outlook.com>
299 Description: 299 Description:
300 This file is used for telling 300 This file is used for telling the kernel an offset into a disk
301 to use when hibernating the sy 301 to use when hibernating the system such as with a swap file.
302 302
303 Reads from this file will disp 303 Reads from this file will display the current offset
304 the kernel will be using on th 304 the kernel will be using on the next hibernation
305 attempt. 305 attempt.
306 306
307 Using this sysfs file will ove 307 Using this sysfs file will override any values that were
308 set using the kernel command l 308 set using the kernel command line for disk offset.
309 309
310 What: /sys/power/suspend_stats 310 What: /sys/power/suspend_stats
311 Date: July 2019 311 Date: July 2019
312 Contact: Kalesh Singh <kaleshsingh96@gma 312 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
313 Description: 313 Description:
314 The /sys/power/suspend_stats d 314 The /sys/power/suspend_stats directory contains suspend related
315 statistics. 315 statistics.
316 316
317 What: /sys/power/suspend_stats/succe 317 What: /sys/power/suspend_stats/success
318 Date: July 2019 318 Date: July 2019
319 Contact: Kalesh Singh <kaleshsingh96@gma 319 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
320 Description: 320 Description:
321 The /sys/power/suspend_stats/s 321 The /sys/power/suspend_stats/success file contains the number
322 of times entering system sleep 322 of times entering system sleep state succeeded.
323 323
324 What: /sys/power/suspend_stats/fail 324 What: /sys/power/suspend_stats/fail
325 Date: July 2019 325 Date: July 2019
326 Contact: Kalesh Singh <kaleshsingh96@gma 326 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
327 Description: 327 Description:
328 The /sys/power/suspend_stats/f 328 The /sys/power/suspend_stats/fail file contains the number
329 of times entering system sleep 329 of times entering system sleep state failed.
330 330
331 What: /sys/power/suspend_stats/faile 331 What: /sys/power/suspend_stats/failed_freeze
332 Date: July 2019 332 Date: July 2019
333 Contact: Kalesh Singh <kaleshsingh96@gma 333 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
334 Description: 334 Description:
335 The /sys/power/suspend_stats/f 335 The /sys/power/suspend_stats/failed_freeze file contains the
336 number of times freezing proce 336 number of times freezing processes failed.
337 337
338 What: /sys/power/suspend_stats/faile 338 What: /sys/power/suspend_stats/failed_prepare
339 Date: July 2019 339 Date: July 2019
340 Contact: Kalesh Singh <kaleshsingh96@gma 340 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
341 Description: 341 Description:
342 The /sys/power/suspend_stats/f 342 The /sys/power/suspend_stats/failed_prepare file contains the
343 number of times preparing all 343 number of times preparing all non-sysdev devices for
344 a system PM transition failed. 344 a system PM transition failed.
345 345
346 What: /sys/power/suspend_stats/faile 346 What: /sys/power/suspend_stats/failed_resume
347 Date: July 2019 347 Date: July 2019
348 Contact: Kalesh Singh <kaleshsingh96@gma 348 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
349 Description: 349 Description:
350 The /sys/power/suspend_stats/f 350 The /sys/power/suspend_stats/failed_resume file contains the
351 number of times executing "res 351 number of times executing "resume" callbacks of
352 non-sysdev devices failed. 352 non-sysdev devices failed.
353 353
354 What: /sys/power/suspend_stats/faile 354 What: /sys/power/suspend_stats/failed_resume_early
355 Date: July 2019 355 Date: July 2019
356 Contact: Kalesh Singh <kaleshsingh96@gma 356 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
357 Description: 357 Description:
358 The /sys/power/suspend_stats/f 358 The /sys/power/suspend_stats/failed_resume_early file contains
359 the number of times executing 359 the number of times executing "early resume" callbacks
360 of devices failed. 360 of devices failed.
361 361
362 What: /sys/power/suspend_stats/faile 362 What: /sys/power/suspend_stats/failed_resume_noirq
363 Date: July 2019 363 Date: July 2019
364 Contact: Kalesh Singh <kaleshsingh96@gma 364 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
365 Description: 365 Description:
366 The /sys/power/suspend_stats/f 366 The /sys/power/suspend_stats/failed_resume_noirq file contains
367 the number of times executing 367 the number of times executing "noirq resume" callbacks
368 of devices failed. 368 of devices failed.
369 369
370 What: /sys/power/suspend_stats/faile 370 What: /sys/power/suspend_stats/failed_suspend
371 Date: July 2019 371 Date: July 2019
372 Contact: Kalesh Singh <kaleshsingh96@gma 372 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
373 Description: 373 Description:
374 The /sys/power/suspend_stats/f 374 The /sys/power/suspend_stats/failed_suspend file contains
375 the number of times executing 375 the number of times executing "suspend" callbacks
376 of all non-sysdev devices fail 376 of all non-sysdev devices failed.
377 377
378 What: /sys/power/suspend_stats/faile 378 What: /sys/power/suspend_stats/failed_suspend_late
379 Date: July 2019 379 Date: July 2019
380 Contact: Kalesh Singh <kaleshsingh96@gma 380 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
381 Description: 381 Description:
382 The /sys/power/suspend_stats/f 382 The /sys/power/suspend_stats/failed_suspend_late file contains
383 the number of times executing 383 the number of times executing "late suspend" callbacks
384 of all devices failed. 384 of all devices failed.
385 385
386 What: /sys/power/suspend_stats/faile 386 What: /sys/power/suspend_stats/failed_suspend_noirq
387 Date: July 2019 387 Date: July 2019
388 Contact: Kalesh Singh <kaleshsingh96@gma 388 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
389 Description: 389 Description:
390 The /sys/power/suspend_stats/f 390 The /sys/power/suspend_stats/failed_suspend_noirq file contains
391 the number of times executing 391 the number of times executing "noirq suspend" callbacks
392 of all devices failed. 392 of all devices failed.
393 393
394 What: /sys/power/suspend_stats/last_ 394 What: /sys/power/suspend_stats/last_failed_dev
395 Date: July 2019 395 Date: July 2019
396 Contact: Kalesh Singh <kaleshsingh96@gma 396 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
397 Description: 397 Description:
398 The /sys/power/suspend_stats/l 398 The /sys/power/suspend_stats/last_failed_dev file contains
399 the last device for which a su 399 the last device for which a suspend/resume callback failed.
400 400
401 What: /sys/power/suspend_stats/last_ 401 What: /sys/power/suspend_stats/last_failed_errno
402 Date: July 2019 402 Date: July 2019
403 Contact: Kalesh Singh <kaleshsingh96@gma 403 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
404 Description: 404 Description:
405 The /sys/power/suspend_stats/l 405 The /sys/power/suspend_stats/last_failed_errno file contains
406 the errno of the last failed a 406 the errno of the last failed attempt at entering
407 system sleep state. 407 system sleep state.
408 408
409 What: /sys/power/suspend_stats/last_ 409 What: /sys/power/suspend_stats/last_failed_step
410 Date: July 2019 410 Date: July 2019
411 Contact: Kalesh Singh <kaleshsingh96@gma 411 Contact: Kalesh Singh <kaleshsingh96@gmail.com>
412 Description: 412 Description:
413 The /sys/power/suspend_stats/l 413 The /sys/power/suspend_stats/last_failed_step file contains
414 the last failed step in the su 414 the last failed step in the suspend/resume path.
415 <<
416 What: /sys/power/suspend_stats/last_ <<
417 Date: June 2023 <<
418 Contact: Mario Limonciello <mario.limonc <<
419 Description: <<
420 The /sys/power/suspend_stats/l <<
421 contains the duration of time <<
422 state in the most recent syste <<
423 This number is measured in mic <<
424 <<
425 What: /sys/power/suspend_stats/total <<
426 Date: June 2023 <<
427 Contact: Mario Limonciello <mario.limonc <<
428 Description: <<
429 The /sys/power/suspend_stats/t <<
430 contains the aggregate of time <<
431 state since the kernel was boo <<
432 is measured in microseconds. <<
433 <<
434 What: /sys/power/suspend_stats/max_h <<
435 Date: June 2023 <<
436 Contact: Mario Limonciello <mario.limonc <<
437 Description: <<
438 The /sys/power/suspend_stats/m <<
439 contains the maximum amount of <<
440 report for time spent in a har <<
441 cycles are longer than this ti <<
442 'total_hw_sleep' and 'last_hw_ <<
443 This number is measured in mic <<
444 415
445 What: /sys/power/sync_on_suspend 416 What: /sys/power/sync_on_suspend
446 Date: October 2019 417 Date: October 2019
447 Contact: Jonas Meurer <jonas@freesources 418 Contact: Jonas Meurer <jonas@freesources.org>
448 Description: 419 Description:
449 This file controls whether or 420 This file controls whether or not the kernel will sync()
450 filesystems during system susp 421 filesystems during system suspend (after freezing user space
451 and before suspending devices) 422 and before suspending devices).
452 423
453 Writing a "1" to this file ena 424 Writing a "1" to this file enables the sync() and writing a "0"
454 disables it. Reads from the f 425 disables it. Reads from the file return the current value.
455 The default is "1" if the buil 426 The default is "1" if the build-time "SUSPEND_SKIP_SYNC" config
456 flag is unset, or "0" otherwis 427 flag is unset, or "0" otherwise.
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