ddi_dma_coff(9F)

NAME | SYNOPSIS | INTERFACE LEVEL | PARAMETERS | DESCRIPTION | RETURN VALUES | CONTEXT | SEE ALSO

NAME

ddi_dma_coff- convert a DMA cookie to an offset within a DMA handle

SYNOPSIS

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

int ddi_dma_coff(ddi_dma_handle_t handle, ddi_dma_cookie_t *cookiep, off_t *offp);

INTERFACE LEVEL

Solaris SPARC DDI (Solaris SPARC DDI).

PARAMETERS

handle

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

cookiep

A pointer to a DMA cookie (see ddi_dma_cookie(9S)) that contains the appropriate address, length and bus type to be used in programming the DMA engine.

offp

A pointer to an offset to be filled in.

DESCRIPTION

ddi_dma_coff() converts the values in DMA cookie pointed to by cookiep to an offset (in bytes) from the beginning of the object that the DMA handle has mapped.

ddi_dma_coff() allows a driver to update a DMA cookie with values it reads from its device's DMA engine after a transfer completes and convert that value into an offset into the object that is mapped for DMA.

RETURN VALUES

ddi_dma_coff() returns:

DDI_SUCCESS

Successfully filled in offp.

DDI_FAILURE

Failed to successfully fill in offp.

CONTEXT

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

SEE ALSO

ddi_dma_setup(9F), ddi_dma_sync(9F), ddi_dma_cookie(9S)

Writing Device Drivers

SunOS 5.8  Last Revised 4 Nov 1991

NAME | SYNOPSIS | INTERFACE LEVEL | PARAMETERS | DESCRIPTION | RETURN VALUES | CONTEXT | SEE ALSO