18c2ecf20Sopenharmony_ciWhat: /sys/class/rtc/rtc0/device/rtc_calibration 28c2ecf20Sopenharmony_ciDate: Oct 2011 38c2ecf20Sopenharmony_ciKernelVersion: 3.0 48c2ecf20Sopenharmony_ciContact: Mark Godfrey <mark.godfrey@stericsson.com> 58c2ecf20Sopenharmony_ciDescription: Attribute for calibrating ST-Ericsson AB8500 Real Time Clock 68c2ecf20Sopenharmony_ci The rtc_calibration attribute allows the userspace to 78c2ecf20Sopenharmony_ci calibrate the AB8500.s 32KHz Real Time Clock. 88c2ecf20Sopenharmony_ci Every 60 seconds the AB8500 will correct the RTC's value 98c2ecf20Sopenharmony_ci by adding to it the value of this attribute. 108c2ecf20Sopenharmony_ci 118c2ecf20Sopenharmony_ci The range of the attribute is -127 to +127 in units of 128c2ecf20Sopenharmony_ci 30.5 micro-seconds (half-parts-per-million of the 32KHz clock) 138c2ecf20Sopenharmony_ciUsers: The /vendor/st-ericsson/base_utilities/core/rtc_calibration 148c2ecf20Sopenharmony_ci daemon uses this interface. 15