ddi_dma_coff(9F) Kernel Functions for Drivers ddi_dma_coff(9F)
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 con-
vert 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 5.10 4 Nov 1991 ddi_dma_coff(9F)
