Advanced Configuration and Power Interface Specification

Advanced Configuration and Power Interface Specification
Note: To maintain compatibility with OSPM implementations of previous revisions of the ACPI
specification, the platform must not rely on OSPM’s evaluation of the _OST object for proper
platform operation.
Example ASL for _OST usage:
External (\_SB.PCI4, DeviceObj)
Scope(\_SB.PCI4) {
OperationRegion(LED1, SystemIO, 0x10C0, 0x20)
Field(LED1, AnyAcc, NoLock, Preserve)
{ // LED controls
S0LE, 1, // Slot 0 Ejection Progress LED
S0LF, 1, // Slot 0 Ejection Failure LED
S1LE, 1, // Slot 1 Ejection Progress LED
S1LF, 1, // Slot 1 Ejection Failure LED
S2LE, 1, // Slot 2 Ejection Progress LED
S2LF, 1, // Slot 2 Ejection Failure LED
S3LE, 1, // Slot 3 Ejection Progress LED
S3LF, 1 // Slot 3 Ejection Failure LED
}
Device(SLT3) {
Name(_ADR, 0x000C0003)
Method(_OST, 3, Serialized) {
// hot plug device
// OS calls _OST with notify code 3 or 0x103
// and status codes 0x80-0x83
// to indicate a hot remove request failure.
// Status code 0x84 indicates an ejection
// request pending.
{
}
If(LEqual(Arg0,Ones))
// Unspecified event
// Perform generic event processing here
Switch(And(Arg0,0xFF))
// Mask to retain low byte
{
Case(0x03)
// Ejection request
{
Switch(Arg1)
{
Case(Package(){0x80, 0x81, 0x82, 0x83})
{ // Ejection Failure for some reason
Store(Zero, ^^S3LE) // Turn off Ejection Progress LED
Store(One, ^^S3LF) // Turn on Ejection Failure LED
}
Case(0x84)
// Eject request pending
{
Store(One, ^^S3LE) // Turn on Ejection Request LED
Store(Zero, ^^S3LF) // Turn off Ejection Failure LED
}
}
}
}
} // end _OST
340 April, 2015 Version 6.0