sysfs-class-power 21 KB

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  1. **General Properties**
  2. What: /sys/class/power_supply/<supply_name>/manufacturer
  3. Date: May 2007
  4. Contact: linux-pm@vger.kernel.org
  5. Description:
  6. Reports the name of the device manufacturer.
  7. Access: Read
  8. Valid values: Represented as string
  9. What: /sys/class/power_supply/<supply_name>/model_name
  10. Date: May 2007
  11. Contact: linux-pm@vger.kernel.org
  12. Description:
  13. Reports the name of the device model.
  14. Access: Read
  15. Valid values: Represented as string
  16. What: /sys/class/power_supply/<supply_name>/serial_number
  17. Date: January 2008
  18. Contact: linux-pm@vger.kernel.org
  19. Description:
  20. Reports the serial number of the device.
  21. Access: Read
  22. Valid values: Represented as string
  23. What: /sys/class/power_supply/<supply_name>/type
  24. Date: May 2010
  25. Contact: linux-pm@vger.kernel.org
  26. Description:
  27. Describes the main type of the supply.
  28. Access: Read
  29. Valid values: "Battery", "UPS", "Mains", "USB", "Wireless"
  30. **Battery and USB properties**
  31. What: /sys/class/power_supply/<supply_name>/current_avg
  32. Date: May 2007
  33. Contact: linux-pm@vger.kernel.org
  34. Description:
  35. Battery:
  36. Reports an average IBAT current reading for the battery, over
  37. a fixed period. Normally devices will provide a fixed interval
  38. in which they average readings to smooth out the reported
  39. value.
  40. USB:
  41. Reports an average IBUS current reading over a fixed period.
  42. Normally devices will provide a fixed interval in which they
  43. average readings to smooth out the reported value.
  44. Access: Read
  45. Valid values: Represented in microamps. Negative values are
  46. used for discharging batteries, positive values for charging
  47. batteries and for USB IBUS current.
  48. What: /sys/class/power_supply/<supply_name>/current_max
  49. Date: October 2010
  50. Contact: linux-pm@vger.kernel.org
  51. Description:
  52. Battery:
  53. Reports the maximum IBAT current allowed into the battery.
  54. USB:
  55. Reports the maximum IBUS current the supply can support.
  56. Access: Read
  57. Valid values: Represented in microamps
  58. What: /sys/class/power_supply/<supply_name>/current_now
  59. Date: May 2007
  60. Contact: linux-pm@vger.kernel.org
  61. Description:
  62. Battery:
  63. Reports an instant, single IBAT current reading for the
  64. battery. This value is not averaged/smoothed.
  65. Access: Read
  66. USB:
  67. Reports the IBUS current supplied now. This value is generally
  68. read-only reporting, unless the 'online' state of the supply
  69. is set to be programmable, in which case this value can be set
  70. within the reported min/max range.
  71. Access: Read, Write
  72. Valid values: Represented in microamps. Negative values are
  73. used for discharging batteries, positive values for charging
  74. batteries and for USB IBUS current.
  75. What: /sys/class/power_supply/<supply_name>/temp
  76. Date: May 2007
  77. Contact: linux-pm@vger.kernel.org
  78. Description:
  79. Battery:
  80. Reports the current TBAT battery temperature reading.
  81. USB:
  82. Reports the current supply temperature reading. This would
  83. normally be the internal temperature of the device itself
  84. (e.g TJUNC temperature of an IC)
  85. Access: Read
  86. Valid values: Represented in 1/10 Degrees Celsius
  87. What: /sys/class/power_supply/<supply_name>/temp_alert_max
  88. Date: July 2012
  89. Contact: linux-pm@vger.kernel.org
  90. Description:
  91. Battery:
  92. Maximum TBAT temperature trip-wire value where the supply will
  93. notify user-space of the event.
  94. USB:
  95. Maximum supply temperature trip-wire value where the supply
  96. will notify user-space of the event.
  97. This is normally used for the charging scenario where
  98. user-space needs to know if the temperature has crossed an
  99. upper threshold so it can take appropriate action (e.g. warning
  100. user that the temperature is critically high, and charging has
  101. stopped).
  102. Access: Read
  103. Valid values: Represented in 1/10 Degrees Celsius
  104. What: /sys/class/power_supply/<supply_name>/temp_alert_min
  105. Date: July 2012
  106. Contact: linux-pm@vger.kernel.org
  107. Description:
  108. Battery:
  109. Minimum TBAT temperature trip-wire value where the supply will
  110. notify user-space of the event.
  111. USB:
  112. Minimum supply temperature trip-wire value where the supply
  113. will notify user-space of the event.
  114. This is normally used for the charging scenario where user-space
  115. needs to know if the temperature has crossed a lower threshold
  116. so it can take appropriate action (e.g. warning user that
  117. temperature level is high, and charging current has been
  118. reduced accordingly to remedy the situation).
  119. Access: Read
  120. Valid values: Represented in 1/10 Degrees Celsius
  121. What: /sys/class/power_supply/<supply_name>/temp_max
  122. Date: July 2014
  123. Contact: linux-pm@vger.kernel.org
  124. Description:
  125. Battery:
  126. Reports the maximum allowed TBAT battery temperature for
  127. charging.
  128. USB:
  129. Reports the maximum allowed supply temperature for operation.
  130. Access: Read
  131. Valid values: Represented in 1/10 Degrees Celsius
  132. What: /sys/class/power_supply/<supply_name>/temp_min
  133. Date: July 2014
  134. Contact: linux-pm@vger.kernel.org
  135. Description:
  136. Battery:
  137. Reports the minimum allowed TBAT battery temperature for
  138. charging.
  139. USB:
  140. Reports the minimum allowed supply temperature for operation.
  141. Access: Read
  142. Valid values: Represented in 1/10 Degrees Celsius
  143. What: /sys/class/power_supply/<supply_name>/voltage_max,
  144. Date: January 2008
  145. Contact: linux-pm@vger.kernel.org
  146. Description:
  147. Battery:
  148. Reports the maximum safe VBAT voltage permitted for the
  149. battery, during charging.
  150. USB:
  151. Reports the maximum VBUS voltage the supply can support.
  152. Access: Read
  153. Valid values: Represented in microvolts
  154. What: /sys/class/power_supply/<supply_name>/voltage_min,
  155. Date: January 2008
  156. Contact: linux-pm@vger.kernel.org
  157. Description:
  158. Battery:
  159. Reports the minimum safe VBAT voltage permitted for the
  160. battery, during discharging.
  161. USB:
  162. Reports the minimum VBUS voltage the supply can support.
  163. Access: Read
  164. Valid values: Represented in microvolts
  165. What: /sys/class/power_supply/<supply_name>/voltage_now,
  166. Date: May 2007
  167. Contact: linux-pm@vger.kernel.org
  168. Description:
  169. Battery:
  170. Reports an instant, single VBAT voltage reading for the
  171. battery. This value is not averaged/smoothed.
  172. Access: Read
  173. USB:
  174. Reports the VBUS voltage supplied now. This value is generally
  175. read-only reporting, unless the 'online' state of the supply
  176. is set to be programmable, in which case this value can be set
  177. within the reported min/max range.
  178. Access: Read, Write
  179. Valid values: Represented in microvolts
  180. **Battery Properties**
  181. What: /sys/class/power_supply/<supply_name>/capacity
  182. Date: May 2007
  183. Contact: linux-pm@vger.kernel.org
  184. Description:
  185. Fine grain representation of battery capacity.
  186. Access: Read
  187. Valid values: 0 - 100 (percent)
  188. What: /sys/class/power_supply/<supply_name>/capacity_alert_max
  189. Date: July 2012
  190. Contact: linux-pm@vger.kernel.org
  191. Description:
  192. Maximum battery capacity trip-wire value where the supply will
  193. notify user-space of the event. This is normally used for the
  194. battery discharging scenario where user-space needs to know the
  195. battery has dropped to an upper level so it can take
  196. appropriate action (e.g. warning user that battery level is
  197. low).
  198. Access: Read, Write
  199. Valid values: 0 - 100 (percent)
  200. What: /sys/class/power_supply/<supply_name>/capacity_alert_min
  201. Date: July 2012
  202. Contact: linux-pm@vger.kernel.org
  203. Description:
  204. Minimum battery capacity trip-wire value where the supply will
  205. notify user-space of the event. This is normally used for the
  206. battery discharging scenario where user-space needs to know the
  207. battery has dropped to a lower level so it can take
  208. appropriate action (e.g. warning user that battery level is
  209. critically low).
  210. Access: Read, Write
  211. Valid values: 0 - 100 (percent)
  212. What: /sys/class/power_supply/<supply_name>/capacity_error_margin
  213. Date: April 2019
  214. Contact: linux-pm@vger.kernel.org
  215. Description:
  216. Battery capacity measurement becomes unreliable without
  217. recalibration. This values provides the maximum error
  218. margin expected to exist by the fuel gauge in percent.
  219. Values close to 0% will be returned after (re-)calibration
  220. has happened. Over time the error margin will increase.
  221. 100% means, that the capacity related values are basically
  222. completely useless.
  223. Access: Read
  224. Valid values: 0 - 100 (percent)
  225. What: /sys/class/power_supply/<supply_name>/capacity_level
  226. Date: June 2009
  227. Contact: linux-pm@vger.kernel.org
  228. Description:
  229. Coarse representation of battery capacity.
  230. Access: Read
  231. Valid values:
  232. "Unknown", "Critical", "Low", "Normal", "High",
  233. "Full"
  234. What: /sys/class/power_supply/<supply_name>/charge_control_limit
  235. Date: Oct 2012
  236. Contact: linux-pm@vger.kernel.org
  237. Description:
  238. Maximum allowable charging current. Used for charge rate
  239. throttling for thermal cooling or improving battery health.
  240. Access: Read, Write
  241. Valid values: Represented in microamps
  242. What: /sys/class/power_supply/<supply_name>/charge_control_limit_max
  243. Date: Oct 2012
  244. Contact: linux-pm@vger.kernel.org
  245. Description:
  246. Maximum legal value for the charge_control_limit property.
  247. Access: Read
  248. Valid values: Represented in microamps
  249. What: /sys/class/power_supply/<supply_name>/charge_control_start_threshold
  250. Date: April 2019
  251. Contact: linux-pm@vger.kernel.org
  252. Description:
  253. Represents a battery percentage level, below which charging will
  254. begin.
  255. Access: Read, Write
  256. Valid values: 0 - 100 (percent)
  257. What: /sys/class/power_supply/<supply_name>/charge_control_end_threshold
  258. Date: April 2019
  259. Contact: linux-pm@vger.kernel.org
  260. Description:
  261. Represents a battery percentage level, above which charging will
  262. stop.
  263. Access: Read, Write
  264. Valid values: 0 - 100 (percent)
  265. What: /sys/class/power_supply/<supply_name>/charge_type
  266. Date: July 2009
  267. Contact: linux-pm@vger.kernel.org
  268. Description:
  269. Represents the type of charging currently being applied to the
  270. battery. "Trickle", "Fast", and "Standard" all mean different
  271. charging speeds. "Adaptive" means that the charger uses some
  272. algorithm to adjust the charge rate dynamically, without
  273. any user configuration required. "Custom" means that the charger
  274. uses the charge_control_* properties as configuration for some
  275. different algorithm.
  276. Access: Read, Write
  277. Valid values:
  278. "Unknown", "N/A", "Trickle", "Fast", "Standard",
  279. "Adaptive", "Custom"
  280. What: /sys/class/power_supply/<supply_name>/charge_term_current
  281. Date: July 2014
  282. Contact: linux-pm@vger.kernel.org
  283. Description:
  284. Reports the charging current value which is used to determine
  285. when the battery is considered full and charging should end.
  286. Access: Read
  287. Valid values: Represented in microamps
  288. What: /sys/class/power_supply/<supply_name>/health
  289. Date: May 2007
  290. Contact: linux-pm@vger.kernel.org
  291. Description:
  292. Reports the health of the battery or battery side of charger
  293. functionality.
  294. Access: Read
  295. Valid values:
  296. "Unknown", "Good", "Overheat", "Dead",
  297. "Over voltage", "Unspecified failure", "Cold",
  298. "Watchdog timer expire", "Safety timer expire",
  299. "Over current", "Calibration required", "Warm",
  300. "Cool", "Hot"
  301. What: /sys/class/power_supply/<supply_name>/precharge_current
  302. Date: June 2017
  303. Contact: linux-pm@vger.kernel.org
  304. Description:
  305. Reports the charging current applied during pre-charging phase
  306. for a battery charge cycle.
  307. Access: Read
  308. Valid values: Represented in microamps
  309. What: /sys/class/power_supply/<supply_name>/present
  310. Date: May 2007
  311. Contact: linux-pm@vger.kernel.org
  312. Description:
  313. Reports whether a battery is present or not in the system.
  314. Access: Read
  315. Valid values:
  316. == =======
  317. 0: Absent
  318. 1: Present
  319. == =======
  320. What: /sys/class/power_supply/<supply_name>/status
  321. Date: May 2007
  322. Contact: linux-pm@vger.kernel.org
  323. Description:
  324. Represents the charging status of the battery. Normally this
  325. is read-only reporting although for some supplies this can be
  326. used to enable/disable charging to the battery.
  327. Access: Read, Write
  328. Valid values:
  329. "Unknown", "Charging", "Discharging",
  330. "Not charging", "Full"
  331. What: /sys/class/power_supply/<supply_name>/technology
  332. Date: May 2007
  333. Contact: linux-pm@vger.kernel.org
  334. Description:
  335. Describes the battery technology supported by the supply.
  336. Access: Read
  337. Valid values:
  338. "Unknown", "NiMH", "Li-ion", "Li-poly", "LiFe",
  339. "NiCd", "LiMn"
  340. What: /sys/class/power_supply/<supply_name>/voltage_avg,
  341. Date: May 2007
  342. Contact: linux-pm@vger.kernel.org
  343. Description:
  344. Reports an average VBAT voltage reading for the battery, over a
  345. fixed period. Normally devices will provide a fixed interval in
  346. which they average readings to smooth out the reported value.
  347. Access: Read
  348. Valid values: Represented in microvolts
  349. **USB Properties**
  350. What: /sys/class/power_supply/<supply_name>/input_current_limit
  351. Date: July 2014
  352. Contact: linux-pm@vger.kernel.org
  353. Description:
  354. Details the incoming IBUS current limit currently set in the
  355. supply. Normally this is configured based on the type of
  356. connection made (e.g. A configured SDP should output a maximum
  357. of 500mA so the input current limit is set to the same value).
  358. Use preferably input_power_limit, and for problems that can be
  359. solved using power limit use input_current_limit.
  360. Access: Read, Write
  361. Valid values: Represented in microamps
  362. What: /sys/class/power_supply/<supply_name>/input_voltage_limit
  363. Date: May 2019
  364. Contact: linux-pm@vger.kernel.org
  365. Description:
  366. This entry configures the incoming VBUS voltage limit currently
  367. set in the supply. Normally this is configured based on
  368. system-level knowledge or user input (e.g. This is part of the
  369. Pixel C's thermal management strategy to effectively limit the
  370. input power to 5V when the screen is on to meet Google's skin
  371. temperature targets). Note that this feature should not be
  372. used for safety critical things.
  373. Use preferably input_power_limit, and for problems that can be
  374. solved using power limit use input_voltage_limit.
  375. Access: Read, Write
  376. Valid values: Represented in microvolts
  377. What: /sys/class/power_supply/<supply_name>/input_power_limit
  378. Date: May 2019
  379. Contact: linux-pm@vger.kernel.org
  380. Description:
  381. This entry configures the incoming power limit currently set
  382. in the supply. Normally this is configured based on
  383. system-level knowledge or user input. Use preferably this
  384. feature to limit the incoming power and use current/voltage
  385. limit only for problems that can be solved using power limit.
  386. Access: Read, Write
  387. Valid values: Represented in microwatts
  388. What: /sys/class/power_supply/<supply_name>/online,
  389. Date: May 2007
  390. Contact: linux-pm@vger.kernel.org
  391. Description:
  392. Indicates if VBUS is present for the supply. When the supply is
  393. online, and the supply allows it, then it's possible to switch
  394. between online states (e.g. Fixed -> Programmable for a PD_PPS
  395. USB supply so voltage and current can be controlled).
  396. Access: Read, Write
  397. Valid values:
  398. == ==================================================
  399. 0: Offline
  400. 1: Online Fixed - Fixed Voltage Supply
  401. 2: Online Programmable - Programmable Voltage Supply
  402. == ==================================================
  403. What: /sys/class/power_supply/<supply_name>/usb_type
  404. Date: March 2018
  405. Contact: linux-pm@vger.kernel.org
  406. Description:
  407. Reports what type of USB connection is currently active for
  408. the supply, for example it can show if USB-PD capable source
  409. is attached.
  410. Access: Read-Only
  411. Valid values:
  412. "Unknown", "SDP", "DCP", "CDP", "ACA", "C", "PD",
  413. "PD_DRP", "PD_PPS", "BrickID"
  414. **Device Specific Properties**
  415. What: /sys/class/power/ds2760-battery.*/charge_now
  416. Date: May 2010
  417. KernelVersion: 2.6.35
  418. Contact: Daniel Mack <daniel@caiaq.de>
  419. Description:
  420. This file is writeable and can be used to set the current
  421. coloumb counter value inside the battery monitor chip. This
  422. is needed for unavoidable corrections of aging batteries.
  423. A userspace daemon can monitor the battery charging logic
  424. and once the counter drops out of considerable bounds, take
  425. appropriate action.
  426. What: /sys/class/power/ds2760-battery.*/charge_full
  427. Date: May 2010
  428. KernelVersion: 2.6.35
  429. Contact: Daniel Mack <daniel@caiaq.de>
  430. Description:
  431. This file is writeable and can be used to set the assumed
  432. battery 'full level'. As batteries age, this value has to be
  433. amended over time.
  434. What: /sys/class/power_supply/max14577-charger/device/fast_charge_timer
  435. Date: October 2014
  436. KernelVersion: 3.18.0
  437. Contact: Krzysztof Kozlowski <krzk@kernel.org>
  438. Description:
  439. This entry shows and sets the maximum time the max14577
  440. charger operates in fast-charge mode. When the timer expires
  441. the device will terminate fast-charge mode (charging current
  442. will drop to 0 A) and will trigger interrupt.
  443. Valid values:
  444. - 5, 6 or 7 (hours),
  445. - 0: disabled.
  446. What: /sys/class/power_supply/max77693-charger/device/fast_charge_timer
  447. Date: January 2015
  448. KernelVersion: 3.19.0
  449. Contact: Krzysztof Kozlowski <krzk@kernel.org>
  450. Description:
  451. This entry shows and sets the maximum time the max77693
  452. charger operates in fast-charge mode. When the timer expires
  453. the device will terminate fast-charge mode (charging current
  454. will drop to 0 A) and will trigger interrupt.
  455. Valid values:
  456. - 4 - 16 (hours), step by 2 (rounded down)
  457. - 0: disabled.
  458. What: /sys/class/power_supply/max77693-charger/device/top_off_threshold_current
  459. Date: January 2015
  460. KernelVersion: 3.19.0
  461. Contact: Krzysztof Kozlowski <krzk@kernel.org>
  462. Description:
  463. This entry shows and sets the charging current threshold for
  464. entering top-off charging mode. When charging current in fast
  465. charge mode drops below this value, the charger will trigger
  466. interrupt and start top-off charging mode.
  467. Valid values:
  468. - 100000 - 200000 (microamps), step by 25000 (rounded down)
  469. - 200000 - 350000 (microamps), step by 50000 (rounded down)
  470. - 0: disabled.
  471. What: /sys/class/power_supply/max77693-charger/device/top_off_timer
  472. Date: January 2015
  473. KernelVersion: 3.19.0
  474. Contact: Krzysztof Kozlowski <krzk@kernel.org>
  475. Description:
  476. This entry shows and sets the maximum time the max77693
  477. charger operates in top-off charge mode. When the timer expires
  478. the device will terminate top-off charge mode (charging current
  479. will drop to 0 A) and will trigger interrupt.
  480. Valid values:
  481. - 0 - 70 (minutes), step by 10 (rounded down)
  482. What: /sys/class/power_supply/bq24257-charger/ovp_voltage
  483. Date: October 2015
  484. KernelVersion: 4.4.0
  485. Contact: Andreas Dannenberg <dannenberg@ti.com>
  486. Description:
  487. This entry configures the overvoltage protection feature of bq24257-
  488. type charger devices. This feature protects the device and other
  489. components against damage from overvoltage on the input supply. See
  490. device datasheet for details.
  491. Valid values:
  492. - 6000000, 6500000, 7000000, 8000000, 9000000, 9500000, 10000000,
  493. 10500000 (all uV)
  494. What: /sys/class/power_supply/bq24257-charger/in_dpm_voltage
  495. Date: October 2015
  496. KernelVersion: 4.4.0
  497. Contact: Andreas Dannenberg <dannenberg@ti.com>
  498. Description:
  499. This entry configures the input dynamic power path management voltage of
  500. bq24257-type charger devices. Once the supply drops to the configured
  501. voltage, the input current limit is reduced down to prevent the further
  502. drop of the supply. When the IC enters this mode, the charge current is
  503. lower than the set value. See device datasheet for details.
  504. Valid values:
  505. - 4200000, 4280000, 4360000, 4440000, 4520000, 4600000, 4680000,
  506. 4760000 (all uV)
  507. What: /sys/class/power_supply/bq24257-charger/high_impedance_enable
  508. Date: October 2015
  509. KernelVersion: 4.4.0
  510. Contact: Andreas Dannenberg <dannenberg@ti.com>
  511. Description:
  512. This entry allows enabling the high-impedance mode of bq24257-type
  513. charger devices. If enabled, it places the charger IC into low power
  514. standby mode with the switch mode controller disabled. When disabled,
  515. the charger operates normally. See device datasheet for details.
  516. Valid values:
  517. - 1: enabled
  518. - 0: disabled
  519. What: /sys/class/power_supply/bq24257-charger/sysoff_enable
  520. Date: October 2015
  521. KernelVersion: 4.4.0
  522. Contact: Andreas Dannenberg <dannenberg@ti.com>
  523. Description:
  524. This entry allows enabling the sysoff mode of bq24257-type charger
  525. devices. If enabled and the input is removed, the internal battery FET
  526. is turned off in order to reduce the leakage from the BAT pin to less
  527. than 1uA. Note that on some devices/systems this disconnects the battery
  528. from the system. See device datasheet for details.
  529. Valid values:
  530. - 1: enabled
  531. - 0: disabled
  532. What: /sys/class/power_supply/<supply_name>/manufacture_year
  533. Date: January 2020
  534. Contact: linux-pm@vger.kernel.org
  535. Description:
  536. Reports the year (following Gregorian calendar) when the device has been
  537. manufactured.
  538. Access: Read
  539. Valid values: Reported as integer
  540. What: /sys/class/power_supply/<supply_name>/manufacture_month
  541. Date: January 2020
  542. Contact: linux-pm@vger.kernel.org
  543. Description:
  544. Reports the month when the device has been manufactured.
  545. Access: Read
  546. Valid values: 1-12
  547. What: /sys/class/power_supply/<supply_name>/manufacture_day
  548. Date: January 2020
  549. Contact: linux-pm@vger.kernel.org
  550. Description:
  551. Reports the day of month when the device has been manufactured.
  552. Access: Read
  553. Valid values: 1-31