Orange Pi5 kernel

What:		/sys/class/rtc/
Date:		March 2006
KernelVersion:	2.6.17
Contact:	linux-rtc@vger.kernel.org
Description:
<------><------>The rtc/ class subdirectory belongs to the RTC subsystem.
 
What:		/sys/class/rtc/rtcX/
Date:		March 2006
KernelVersion:	2.6.17
Contact:	linux-rtc@vger.kernel.org
Description:
<------><------>The /sys/class/rtc/rtc{0,1,2,3,...} directories correspond
<------><------>to each RTC device.
 
What:		/sys/class/rtc/rtcX/date
Date:		March 2006
KernelVersion:	2.6.17
Contact:	linux-rtc@vger.kernel.org
Description:
<------><------>(RO) RTC-provided date in YYYY-MM-DD format
 
What:		/sys/class/rtc/rtcX/hctosys
Date:		September 2009
KernelVersion:	2.6.32
Contact:	linux-rtc@vger.kernel.org
Description:
<------><------>(RO) 1 if the RTC provided the system time at boot via the
<------><------>CONFIG_RTC_HCTOSYS kernel option, 0 otherwise
 
What:		/sys/class/rtc/rtcX/max_user_freq
Date:		October 2007
KernelVersion:	2.6.24
Contact:	linux-rtc@vger.kernel.org
Description:
<------><------>(RW) The maximum interrupt rate an unprivileged user may request
<------><------>from this RTC.
 
What:		/sys/class/rtc/rtcX/name
Date:		March 2006
KernelVersion:	2.6.17
Contact:	linux-rtc@vger.kernel.org
Description:
<------><------>(RO) The name of the RTC corresponding to this sysfs directory
 
What:		/sys/class/rtc/rtcX/range
Date:		January 2018
KernelVersion:	4.16
Contact:	linux-rtc@vger.kernel.org
Description:
<------><------>Valid time range for the RTC, as seconds from epoch, formatted
<------><------>as [min, max]
 
What:		/sys/class/rtc/rtcX/since_epoch
Date:		March 2006
KernelVersion:	2.6.17
Contact:	linux-rtc@vger.kernel.org
Description:
<------><------>(RO) RTC-provided time as the number of seconds since the epoch
 
What:		/sys/class/rtc/rtcX/time
Date:		March 2006
KernelVersion:	2.6.17
Contact:	linux-rtc@vger.kernel.org
Description:
<------><------>(RO) RTC-provided time in 24-hour notation (hh:mm:ss)
 
What:		/sys/class/rtc/rtcX/offset
Date:		February 2016
KernelVersion:	4.6
Contact:	linux-rtc@vger.kernel.org
Description:
<------><------>(RW) The amount which the rtc clock has been adjusted in
<------><------>firmware. Visible only if the driver supports clock offset
<------><------>adjustment. The unit is parts per billion, i.e. The number of
<------><------>clock ticks which are added to or removed from the rtc's base
<------><------>clock per billion ticks. A positive value makes a day pass more
<------><------>slowly, longer, and a negative value makes a day pass more
<------><------>quickly.
 
What:		/sys/class/rtc/rtcX/wakealarm
Date:		February 2007
KernelVersion:	2.6.20
Contact:	linux-rtc@vger.kernel.org
Description:
<------><------>(RW) The time at which the clock will generate a system wakeup
<------><------>event. This is a one shot wakeup event, so must be reset after
<------><------>wake if a daily wakeup is required. Format is seconds since the
<------><------>epoch by default, or if there's a leading +, seconds in the
<------><------>future, or if there is a leading +=, seconds ahead of the
<------><------>current alarm.