opensolaris man page for ddi_device_zero

ddi_device_zero(9F)					   Kernel Functions for Drivers 				       ddi_device_zero(9F)

NAME
       ddi_device_zero - zero fill the device

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

       int ddi_device_zero(ddi_acc_handle_t handle, caddr_t dev_addr,
	    size_t bytecount, ssize_t dev_advcnt, uint_t dev_datasz);

INTERFACE LEVEL
       Solaris DDI specific (Solaris DDI).

PARAMETERS
       handle	      The data access handle returned from setup calls, such as ddi_regs_map_setup(9F).

       dev_addr       Beginning of the device address.

       bytecount      Number of bytes to zero.

       dev_advcnt     Number of  dev_datasz units to advance on every access.

       dev_datasz     The size of each data word. Possible values are defined as:

		      DDI_DATA_SZ01_ACC     1 byte data size

		      DDI_DATA_SZ02_ACC     2 bytes data size

		      DDI_DATA_SZ04_ACC     4 bytes data size

		      DDI_DATA_SZ08_ACC     8 bytes data size

DESCRIPTION
       ddi_device_zero() function fills the given, bytecount, number of byte of zeroes to the device register or memory.

       The   dev_advcnt  argument  determines  the value of the device address,  dev_addr, on each access.  A value of	0 will use the same device
       address,  dev_addr, on every  access. A positive value increments the device address in the next access while a negative  value	decrements
       the address. The device address is incremented and decremented in  dev_datasz units.

       The dev_datasz argument determines the size of data word on each access.

RETURN VALUES
       ddi_device_zero() returns:

       DDI_SUCCESS     Successfully zeroed the data.

       DDI_FAILURE     The byte count is not a multiple of  dev_datasz.

CONTEXT
       ddi_device_zero() can be called from user, kernel, or interrupt context.

SEE ALSO
       ddi_regs_map_free(9F), ddi_regs_map_setup(9F)

       Writing Device Drivers

SunOS 5.11							    25 Sep 1996 					       ddi_device_zero(9F)