rtc: Document RTC_VL_READ and RTC_VL_CLR ioctls
RTC_VL_READ and RTC_VL_CLR have been introduced in 2012 with commit
0f20b767e2
("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: Alexandre Belloni <alexandre.belloni@bootlin.com>
This commit is contained in:
parent
3431ca4837
commit
790a19f18a
|
@ -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
|
||||
|
|
Loading…
Reference in New Issue