UserGetDMASpecification
Gets the controller-specific direct memory access (DMA) specification in response to a call from the framework.
Declaration
virtual kern_return_t UserGetDMASpecification(uint64_t *maxTransferSize, uint32_t *alignment, uint8_t *numAddressBits, DMAOutputSegmentType *segmentType);Parameters
- maxTransferSize:
The maximum allowable transfer size for the controller.
- alignment:
The required alignment for the controller.
- numAddressBits:
The number of bits that the hardware uses on its internal address bus.
- segmentType:
On return, set this output segment type according to the endianness of the hardware.
Return Value
A value that indicates the result of getting the DMA specification. kIOReturnSuccess indicates success. For error definitions, see IOKit Constants.