Viewing file:  devops.c (1.89 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/* $Id: devops.c,v 1.13 2000/08/26 02:38:03 anton Exp $
* devops.c: Device operations using the PROM.
*
* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <asm/openprom.h>
#include <asm/oplib.h>
extern void restore_current(void);
/* Open the device described by the string 'dstr'. Returns the handle
* to that device used for subsequent operations on that device.
* Returns -1 on failure.
*/
int
prom_devopen(char *dstr)
{
int handle;
unsigned long flags;
spin_lock_irqsave(&prom_lock, flags);
switch(prom_vers) {
case PROM_V0:
handle = (*(romvec->pv_v0devops.v0_devopen))(dstr);
if(handle == 0) handle = -1;
break;
case PROM_V2:
case PROM_V3:
handle = (*(romvec->pv_v2devops.v2_dev_open))(dstr);
break;
default:
handle = -1;
break;
};
restore_current();
spin_unlock_irqrestore(&prom_lock, flags);
return handle;
}
/* Close the device described by device handle 'dhandle'. */
int
prom_devclose(int dhandle)
{
unsigned long flags;
spin_lock_irqsave(&prom_lock, flags);
switch(prom_vers) {
case PROM_V0:
(*(romvec->pv_v0devops.v0_devclose))(dhandle);
break;
case PROM_V2:
case PROM_V3:
(*(romvec->pv_v2devops.v2_dev_close))(dhandle);
break;
default:
break;
};
restore_current();
spin_unlock_irqrestore(&prom_lock, flags);
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)
{
unsigned long flags;
spin_lock_irqsave(&prom_lock, flags);
switch(prom_vers) {
case PROM_V0:
(*(romvec->pv_v0devops.v0_seekdev))(dhandle, seekhi, seeklo);
break;
case PROM_V2:
case PROM_V3:
(*(romvec->pv_v2devops.v2_dev_seek))(dhandle, seekhi, seeklo);
break;
default:
break;
};
restore_current();
spin_unlock_irqrestore(&prom_lock, flags);
return;
}
|