Commit 790a19f1 authored by Alexandre Belloni's avatar Alexandre Belloni
Browse files

rtc: Document RTC_VL_READ and RTC_VL_CLR ioctls 

RTC_VL_READ and RTC_VL_CLR have been introduced in 2012 with commit
0f20b767 ("drivers/rtc/rtc-pcf8563.c: add RTC_VL_READ/RTC_VL_CLR ioctl
feature")

Document them now that they have been unified.

Link: https://lore.kernel.org/r/20191214220259.621996-3-alexandre.belloni@bootlin.com


Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent 3431ca48

Documentation/ABI/testing/rtc-cdev

+8 −0
Original line number Diff line number Diff line
@@ -33,6 +33,14 @@ Description: 
		  Requires a separate RTC_PIE_ON call to enable the periodic

		  interrupts.



		* RTC_VL_READ: Read the voltage inputs status of the RTC when

		  supported. The value is a bit field of RTC_VL_*, giving the

		  status of the main and backup voltages.



		* RTC_VL_CLEAR: Clear the voltage status of the RTC. Some RTCs

		  need user interaction when the backup power provider is

		  replaced or charged to be able to clear the status.



		The ioctl() calls supported by the older /dev/rtc interface are

		also supported by the newer RTC class framework. However,

		because the chips and systems are not standardized, some PC/AT