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/* $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; } |