Advanced Configuration and Power Interface Specification

Advanced Configuration and Power Interface Specification
OperationRegion(TOP1, GenericSerialBus, 0x00, 0x100) //Initial offset is 0
Field(TOP1, BufferAcc, NoLock, Preserve)
{
Connection(I2CSerialBus(0x5a,,100000,, "\_SB.I2C",,,,RawDataBuffer(){1,6}))
Offset(0x0),
AccessAs(BufferAcc, AttribBytes (4)),
TFK1, 8, //TFK1 at command value offset 0
TFK2, 8 //TFK2 at command value offset 1
Connection(I2CSerialBus(0x5c,,100000,, "\_SB.I2C",,,,RawDataBuffer(){3,1}))
Offset(0x0),
AccessAs(BufferAcc, AttribBytes (12)),
TS1, 8 //TS1 at command value offset 2
}
Field(TOP1, BufferAcc, NoLock, Preserve)
{
Connection(I2CSerialBus(0x5b,,100000,, "\_SB.I2C",,,,RawDataBuffer(){2,9}))
AccessAs(BufferAcc, AttribByte),
TM1, 8 //TM1 at command value offset 0
}
5.5.2.4.5.2 Declaring and Using a GenericSerialBus Data Buffer
The use of a data buffer for GenericSerialBus transactions allows AML to receive status and data
length values, as well as making it possible to implement the Process Call protocol. The BufferAcc
access type is used to indicate to the field handler that a region-specific data buffer will be used.
For GenericSerialBus operation regions, this data buffer is defined as an arbitrary length buffer that,
if represented using a ‘C’-styled declaration, would be modeled as follows:
typedef struct
{
BYTEStatus; // Byte 0 of the data buffer
BYTELength; // Byte 1 of the data buffer
BYTE[x-1]Data; // Bytes 2-x of the arbitrary length data buffer,
} // where x is the last index of the overall buffer
Where:
• Status (byte 0) indicates the status code of a given GenericSerialBus transaction.
• Length (byte 1) specifies the number of bytes of valid data that exists in the data buffer. Use of
this field is only defined for the Read/Write Block protocol. For other protocols—where the data
length is implied by the protocol—this field is reserved.
• Data (bytes 2-x) represents an arbitrary length buffer, and is the location where actual data is
stored.
For example, the following ASL shows the use of the GenericSerialBus data buffer for performing
transactions to a Smart Battery device.
232 April, 2015 Version 6.0