devops.c

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/* $Id: devops.c,v 1.3 1997/10/29 07:43:28 ecd Exp $
 * devops.c:  Device operations using the PROM.
 *
 * Copyright (C) 1995 David S. Miller ([e-mail])
 * Copyright (C) 1996,1997 Jakub Jelinek ([e-mail])
 */
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>

#include <asm/openprom.h>
#include <asm/oplib.h>

/* Open the device described by the string 'dstr'.  Returns the handle
 * to that device used for subsequent operations on that device.
 * Returns 0 on failure.
 */
int
prom_devopen(char *dstr)
{
	return p1275_cmd ("open", P1275_ARG(0,P1275_ARG_IN_STRING)|
				  P1275_INOUT(1,1),
				  dstr);
}

/* Close the device described by device handle 'dhandle'. */
int
prom_devclose(int dhandle)
{
	p1275_cmd ("close", P1275_INOUT(1,0), dhandle);
	return 0;
}

/* Seek to specified location described by 'seekhi' and 'seeklo'
 * for device 'dhandle'.
 */
void
prom_seek(int dhandle, unsigned int seekhi, unsigned int seeklo)
{
	p1275_cmd ("seek", P1275_INOUT(3,1), dhandle, seekhi, seeklo);
}