NAME

ddi_dma_curwin - report current DMA window offset and size

SYNOPSIS

#include <sys/conf.h>

#include <sys/ddi.h>
#include <sys/sunddi.h>

int ddi_dma_curwin(ddi_dma_handle_t handle, off_t * offp,u_int * lenp);

ARGUMENTS

handle

The DMA handle filled in by a call to ddi_dma_setup(9F).

offp

A pointer to a value which will be filled in with the current offset from the beginning of the object that is mapped for DMA.

lenp

A pointer to a value which will be filled in with the size, in bytes, of the current window onto the object that is mapped for DMA.

INTERFACE LEVEL

Solaris SPARC DDI specific (Solaris SPARC DDI).

DESCRIPTION

ddi_dma_curwin( ) reports the current DMA window offset and size. If a DMA mapping allows partial mapping, that is if the DDI_DMA_PARTIAL flag in the ddi_dma_req(9S) structure is set, its current (effective) DMA window offset and size can be obtained by a call to ddi_dma_curwin( ).

RETURN VALUES

ddi_dma_curwin( ) returns:

DDI_SUCCESS

The current length and offset can be established.

DDI_FAILURE

Otherwise.

CONTEXT

ddi_dma_curwin( ) can be called from user or interrupt context.

SEE ALSO

ddi_dma_movwin(9F), ddi_dma_setup(9F), ddi_dma_req(9S)

Writing Device Drivers