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Diffstat (limited to 'Documentation/ABI/testing/rtc-cdev')
| -rw-r--r-- | Documentation/ABI/testing/rtc-cdev | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/rtc-cdev b/Documentation/ABI/testing/rtc-cdev index 97447283f13b..25910c3c3d7e 100644 --- a/Documentation/ABI/testing/rtc-cdev +++ b/Documentation/ABI/testing/rtc-cdev @@ -33,6 +33,14 @@ Description: Requires a separate RTC_PIE_ON call to enable the periodic interrupts. + * RTC_VL_READ: Read the voltage inputs status of the RTC when + supported. The value is a bit field of RTC_VL_*, giving the + status of the main and backup voltages. + + * RTC_VL_CLEAR: Clear the voltage status of the RTC. Some RTCs + need user interaction when the backup power provider is + replaced or charged to be able to clear the status. + The ioctl() calls supported by the older /dev/rtc interface are also supported by the newer RTC class framework. However, because the chips and systems are not standardized, some PC/AT |