xref: /linux/Documentation/ABI/testing/sysfs-class-rtc-rtc0-device-rtc_calibration (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1What:           Attribute for calibrating ST-Ericsson AB8500 Real Time Clock
2Date:           Oct 2011
3KernelVersion:  3.0
4Contact:        Mark Godfrey <mark.godfrey@stericsson.com>
5Description:    The rtc_calibration attribute allows the userspace to
6                calibrate the AB8500.s 32KHz Real Time Clock.
7                Every 60 seconds the AB8500 will correct the RTC's value
8                by adding to it the value of this attribute.
9                The range of the attribute is -127 to +127 in units of
10                30.5 micro-seconds (half-parts-per-million of the 32KHz clock)
11Users:          The /vendor/st-ericsson/base_utilities/core/rtc_calibration
12                daemon uses this interface.
13