0001 What: /sys/class/rtc/
0002 Date: March 2006
0003 KernelVersion: 2.6.17
0004 Contact: linux-rtc@vger.kernel.org
0005 Description:
0006 The rtc/ class subdirectory belongs to the RTC subsystem.
0007
0008 What: /sys/class/rtc/rtcX/
0009 Date: March 2006
0010 KernelVersion: 2.6.17
0011 Contact: linux-rtc@vger.kernel.org
0012 Description:
0013 The /sys/class/rtc/rtc{0,1,2,3,...} directories correspond
0014 to each RTC device.
0015
0016 What: /sys/class/rtc/rtcX/date
0017 Date: March 2006
0018 KernelVersion: 2.6.17
0019 Contact: linux-rtc@vger.kernel.org
0020 Description:
0021 (RO) RTC-provided date in YYYY-MM-DD format
0022
0023 What: /sys/class/rtc/rtcX/hctosys
0024 Date: September 2009
0025 KernelVersion: 2.6.32
0026 Contact: linux-rtc@vger.kernel.org
0027 Description:
0028 (RO) 1 if the RTC provided the system time at boot via the
0029 CONFIG_RTC_HCTOSYS kernel option, 0 otherwise
0030
0031 What: /sys/class/rtc/rtcX/max_user_freq
0032 Date: October 2007
0033 KernelVersion: 2.6.24
0034 Contact: linux-rtc@vger.kernel.org
0035 Description:
0036 (RW) The maximum interrupt rate an unprivileged user may request
0037 from this RTC.
0038
0039 What: /sys/class/rtc/rtcX/name
0040 Date: March 2006
0041 KernelVersion: 2.6.17
0042 Contact: linux-rtc@vger.kernel.org
0043 Description:
0044 (RO) The name of the RTC corresponding to this sysfs directory
0045
0046 What: /sys/class/rtc/rtcX/range
0047 Date: January 2018
0048 KernelVersion: 4.16
0049 Contact: linux-rtc@vger.kernel.org
0050 Description:
0051 Valid time range for the RTC, as seconds from epoch, formatted
0052 as [min, max]
0053
0054 What: /sys/class/rtc/rtcX/since_epoch
0055 Date: March 2006
0056 KernelVersion: 2.6.17
0057 Contact: linux-rtc@vger.kernel.org
0058 Description:
0059 (RO) RTC-provided time as the number of seconds since the epoch
0060
0061 What: /sys/class/rtc/rtcX/time
0062 Date: March 2006
0063 KernelVersion: 2.6.17
0064 Contact: linux-rtc@vger.kernel.org
0065 Description:
0066 (RO) RTC-provided time in 24-hour notation (hh:mm:ss)
0067
0068 What: /sys/class/rtc/rtcX/offset
0069 Date: February 2016
0070 KernelVersion: 4.6
0071 Contact: linux-rtc@vger.kernel.org
0072 Description:
0073 (RW) The amount which the rtc clock has been adjusted in
0074 firmware. Visible only if the driver supports clock offset
0075 adjustment. The unit is parts per billion, i.e. The number of
0076 clock ticks which are added to or removed from the rtc's base
0077 clock per billion ticks. A positive value makes a day pass more
0078 slowly, longer, and a negative value makes a day pass more
0079 quickly.
0080
0081 What: /sys/class/rtc/rtcX/wakealarm
0082 Date: February 2007
0083 KernelVersion: 2.6.20
0084 Contact: linux-rtc@vger.kernel.org
0085 Description:
0086 (RW) The time at which the clock will generate a system wakeup
0087 event. This is a one shot wakeup event, so must be reset after
0088 wake if a daily wakeup is required. Format is seconds since the
0089 epoch by default, or if there's a leading +, seconds in the
0090 future, or if there is a leading +=, seconds ahead of the
0091 current alarm.
