Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / Documentation / ABI / testing / sysfs-class-rtc-rtc0-device-rtc_calibration

diff --git a/kernel/Documentation/ABI/testing/sysfs-class-rtc-rtc0-device-rtc_calibration b/kernel/Documentation/ABI/testing/sysfs-class-rtc-rtc0-device-rtc_calibration
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+What:           Attribute for calibrating ST-Ericsson AB8500 Real Time Clock
+Date:           Oct 2011
+KernelVersion:  3.0
+Contact:        Mark Godfrey <mark.godfrey@stericsson.com>
+Description:    The rtc_calibration attribute allows the userspace to
+                calibrate the AB8500.s 32KHz Real Time Clock.
+                Every 60 seconds the AB8500 will correct the RTC's value
+                by adding to it the value of this attribute.
+                The range of the attribute is -127 to +127 in units of
+                30.5 micro-seconds (half-parts-per-million of the 32KHz clock)
+Users:          The /vendor/st-ericsson/base_utilities/core/rtc_calibration
+                daemon uses this interface.