4 Contact: linux-rtc@vger.kernel.org
6 The rtc/ class subdirectory belongs to the RTC subsystem.
8 What: /sys/class/rtc/rtcX/
11 Contact: linux-rtc@vger.kernel.org
13 The /sys/class/rtc/rtc{0,1,2,3,...} directories correspond
16 What: /sys/class/rtc/rtcX/date
19 Contact: linux-rtc@vger.kernel.org
21 (RO) RTC-provided date in YYYY-MM-DD format
23 What: /sys/class/rtc/rtcX/hctosys
26 Contact: linux-rtc@vger.kernel.org
28 (RO) 1 if the RTC provided the system time at boot via the
29 CONFIG_RTC_HCTOSYS kernel option, 0 otherwise
31 What: /sys/class/rtc/rtcX/max_user_freq
34 Contact: linux-rtc@vger.kernel.org
36 (RW) The maximum interrupt rate an unprivileged user may request
39 What: /sys/class/rtc/rtcX/name
42 Contact: linux-rtc@vger.kernel.org
44 (RO) The name of the RTC corresponding to this sysfs directory
46 What: /sys/class/rtc/rtcX/since_epoch
49 Contact: linux-rtc@vger.kernel.org
51 (RO) RTC-provided time as the number of seconds since the epoch
53 What: /sys/class/rtc/rtcX/time
56 Contact: linux-rtc@vger.kernel.org
58 (RO) RTC-provided time in 24-hour notation (hh:mm:ss)
60 What: /sys/class/rtc/rtcX/*/nvmem
63 Contact: linux-rtc@vger.kernel.org
65 (RW) The non volatile storage exported as a raw file, as
66 described in Documentation/nvmem/nvmem.txt
68 What: /sys/class/rtc/rtcX/offset
71 Contact: linux-rtc@vger.kernel.org
73 (RW) The amount which the rtc clock has been adjusted in
74 firmware. Visible only if the driver supports clock offset
75 adjustment. The unit is parts per billion, i.e. The number of
76 clock ticks which are added to or removed from the rtc's base
77 clock per billion ticks. A positive value makes a day pass more
78 slowly, longer, and a negative value makes a day pass more
81 What: /sys/class/rtc/rtcX/wakealarm
84 Contact: linux-rtc@vger.kernel.org
86 (RW) The time at which the clock will generate a system wakeup
87 event. This is a one shot wakeup event, so must be reset after
88 wake if a daily wakeup is required. Format is seconds since the
89 epoch by default, or if there's a leading +, seconds in the
90 future, or if there is a leading +=, seconds ahead of the