Intel Extensible Firmware Interface - Manual (Page 206)

Extensible Firmware Interface Specification
6-14 12/01/02 Version 1.10
GetWakeupTime()
Summary
Returns the current wakeup alarm clock setting.
Prototype
EFI_STATUS
GetWakeupTime (
OUT BOOLEAN *Enabled,
OUT BOOLEAN *Pending,
OUT EFI_TIME *Time
);
Parameters
Enabled Indicates if the alarm is currently enabled or disabled.
Pending Indicates if the alarm signal is pending and requires acknowledgement.
Time The current alarm setting. Type EFI_TIME is defined in the
GetTime() function description.
Description
The alarm clock time may be rounded from the set alarm clock time to be within the resolution of
the alarm clock device. The resolution of the alarm clock device is defined to be one second.
During runtime, if a PC-AT CMOS device is present in the platform the caller must synchronize
access to the device before calling
GetWakeupTime() .
Status Codes Returned
EFI_SUCCESS The alarm settings were returned.
EFI_INVALID_PARAMETER Enabled is NULL .
EFI_INVALID_PARAMETER Pending is NULL .
EFI_INVALID_PARAMETER Time is NULL .
EFI_DEVICE_ERROR The wakeup time could not be retrieved due to a hardware error.
EFI_UNSUPPORTED A wakeup timer is not supported on this platform.