Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) What:		/dev/rtcX
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) Date:		April 2005
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3) KernelVersion:	2.6.12
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4) Contact:	linux-rtc@vger.kernel.org
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) Description:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) 		The ioctl interface to drivers for real-time clocks (RTCs).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) 		Following actions are supported:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) 		* RTC_RD_TIME, RTC_SET_TIME: Read or set the RTC time. Time
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) 		  format is a Gregorian calendar date and 24 hour wall clock
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) 		  time.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) 		* RTC_AIE_ON, RTC_AIE_OFF: Enable or disable the alarm interrupt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 		  for RTCs that support alarms
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 		* RTC_ALM_READ, RTC_ALM_SET: Read or set the alarm time for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 		  RTCs that support alarms. Can be set upto 24 hours in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 		  future. Requires a separate RTC_AIE_ON call to enable the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 		  alarm interrupt. (Prefer to use RTC_WKALM_*)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 		* RTC_WKALM_RD, RTC_WKALM_SET: For RTCs that support a more
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 		  powerful interface, which can issue alarms beyond 24 hours and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 		  enable IRQs in the same request.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 		* RTC_PIE_ON, RTC_PIE_OFF: Enable or disable the periodic
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 		  interrupt for RTCs that support periodic interrupts.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 		* RTC_UIE_ON, RTC_UIE_OFF: Enable or disable the update
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 		  interrupt for RTCs that support it.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 		* RTC_IRQP_READ, RTC_IRQP_SET: Read or set the frequency for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 		  periodic interrupts for RTCs that support periodic interrupts.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 		  Requires a separate RTC_PIE_ON call to enable the periodic
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 		  interrupts.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 		* RTC_VL_READ: Read the voltage inputs status of the RTC when
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 		  supported. The value is a bit field of RTC_VL_*, giving the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 		  status of the main and backup voltages.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 		* RTC_VL_CLEAR: Clear the voltage status of the RTC. Some RTCs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 		  need user interaction when the backup power provider is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 		  replaced or charged to be able to clear the status.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 		The ioctl() calls supported by the older /dev/rtc interface are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 		also supported by the newer RTC class framework. However,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 		because the chips and systems are not standardized, some PC/AT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 		functionality might not be provided. And in the same way, some
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 		newer features -- including those enabled by ACPI -- are exposed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 		by the RTC class framework, but can't be supported by the older
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 		driver.