mirror of https://gitee.com/openkylin/linux.git
68 lines
1.3 KiB
C
68 lines
1.3 KiB
C
/*
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* devops.c: Device operations using the PROM.
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*
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* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
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* Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
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*/
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <asm/openprom.h>
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#include <asm/oplib.h>
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/* Open the device described by the string 'dstr'. Returns the handle
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* to that device used for subsequent operations on that device.
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* Returns 0 on failure.
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*/
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int
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prom_devopen(const char *dstr)
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{
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unsigned long args[5];
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args[0] = (unsigned long) "open";
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args[1] = 1;
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args[2] = 1;
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args[3] = (unsigned long) dstr;
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args[4] = (unsigned long) -1;
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p1275_cmd_direct(args);
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return (int) args[4];
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}
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/* Close the device described by device handle 'dhandle'. */
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int
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prom_devclose(int dhandle)
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{
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unsigned long args[4];
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args[0] = (unsigned long) "close";
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args[1] = 1;
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args[2] = 0;
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args[3] = (unsigned int) dhandle;
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p1275_cmd_direct(args);
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return 0;
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}
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/* Seek to specified location described by 'seekhi' and 'seeklo'
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* for device 'dhandle'.
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*/
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void
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prom_seek(int dhandle, unsigned int seekhi, unsigned int seeklo)
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{
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unsigned long args[7];
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args[0] = (unsigned long) "seek";
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args[1] = 3;
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args[2] = 1;
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args[3] = (unsigned int) dhandle;
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args[4] = seekhi;
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args[5] = seeklo;
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args[6] = (unsigned long) -1;
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p1275_cmd_direct(args);
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}
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