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