/*

    isaset.c - isaset, a user-space program to write ISA registers

    Copyright (C) 2000  Frodo Looijaard <frodol@dds.nl>, and

                        Mark D. Studebaker <mdsxyz123@yahoo.com>

    Copyright (C) 2004-2011  Jean Delvare <jdelvare@suse.de>

    This program is free software; you can redistribute it and/or modify

    it under the terms of the GNU General Public License as published by

    the Free Software Foundation; either version 2 of the License, or

    (at your option) any later version.

    This program is distributed in the hope that it will be useful,

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License

    along with this program; if not, write to the Free Software

    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

    MA 02110-1301 USA.

*/

/*

	Typical usage:

	isaset 0x295 0x296 0x10 0x12	Write 0x12 to address 0x10 using address/data registers

	isaset -f 0x5010 0x12		Write 0x12 to location 0x5010

*/

#include <sys/io.h>

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <string.h>

#include "util.h"

#ifdef __powerpc__

unsigned long isa_io_base = 0; /* XXX for now */

#endif /* __powerpc__ */

static void help(void)

{

	fprintf(stderr,

	        "Syntax for I2C-like access:\n"

	        "  isaset [OPTIONS] ADDRREG DATAREG ADDRESS VALUE [MASK]\n"

	        "Syntax for flat address space:\n"

	        "  isaset -f [OPTIONS] ADDRESS VALUE [MASK]\n"

		"Options:\n"

		"  -f	Enable flat address space mode\n"

		"  -y	Assume affirmative answer to all questions\n"

		"  -W	Write a word (16-bit) value\n"

		"  -L	Write a long (32-bit) value\n");

}

int main(int argc, char *argv[])

{

	int addrreg, datareg = 0, addr = 0;

	unsigned long value, vmask = 0, maxval = 0xff, res;

	int flags = 0;

	int flat = 0, yes = 0, width = 1;

	char *end;

	/* handle (optional) flags first */

	while (1+flags < argc && argv[1+flags][0] == '-') {

		switch (argv[1+flags][1]) {

		case 'f': flat = 1; break;

		case 'y': yes = 1; break;

		case 'W': width = 2; maxval = 0xffff; break;

		case 'L': width = 4; maxval = 0xffffffff; break;

		default:

			fprintf(stderr, "Warning: Unsupported flag "

				"\"-%c\"!\n", argv[1+flags][1]);

			help();

			exit(1);

		}

		flags++;

	}

	/* verify that the argument count is correct */

	if ((!flat && (argc < 1+flags+4 || argc > 1+flags+5))

	 || (flat && (argc < 1+flags+2 || argc > 1+flags+3))) {

		help();

		exit(1);

	}

	addrreg = strtol(argv[1+flags], &end, 0);

	if (*end) {

		fprintf(stderr, "Error: Invalid address!\n");

		help();

		exit(1);

	}

	if (addrreg < 0 || addrreg > (flat?0xffff:0x3fff)) {

		fprintf(stderr,

		        "Error: Address out of range (0x0000-0x%04x)!\n",

			flat?0xffff:0x3fff);

		help();

		exit(1);

	}

	if (!flat) {

		datareg = strtol(argv[1+flags+1], &end, 0);

		if (*end) {

			fprintf(stderr, "Error: Invalid data register!\n");

			help();

			exit(1);

		}

		if (datareg < 0 || datareg > 0x3fff) {

			fprintf(stderr, "Error: Data register out of range "

			        "(0x0000-0x3fff)!\n");

			help();

			exit(1);

		}

		addr = strtol(argv[1+flags+2], &end, 0);

		if (*end) {

			fprintf(stderr, "Error: Invalid address!\n");

			help();

			exit(1);

		}

		if (addr < 0 || addr > 0xff) {

			fprintf(stderr, "Error: Address out of range "

			        "(0x00-0xff)!\n");

			help();

			exit(1);

		}

	}

	/* rest is the same for both modes so we cheat on flags */

	if (!flat)

		flags += 2;

	value = strtoul(argv[flags+2], &end, 0);

	if (*end) {

		fprintf(stderr, "Error: Invalid value!\n");

		help();

		exit(1);

	}

	if (value > maxval) {

		fprintf(stderr, "Error: Value out of range "

			"(0x%0*u-%0*lu)!\n", width * 2, 0, width * 2, maxval);

		help();

		exit(1);

	}

	if (flags+3 < argc) {

		vmask = strtoul(argv[flags+3], &end, 0);

		if (*end) {

			fprintf(stderr, "Error: Invalid mask!\n");

			help();

			exit(1);

		}

		if (vmask > maxval) {

			fprintf(stderr, "Error: Mask out of range "

				"(0x%0*u-%0*lu)!\n", width * 2, 0,

				width * 2, maxval);

			help();

			exit(1);

		}

	}

	if (geteuid()) {

		fprintf(stderr, "Error: Can only be run as root "

		        "(or make it suid root)\n");

		exit(1);

	}

	if (!yes) {

		fprintf(stderr, "WARNING! Running this program can cause "

		        "system crashes, data loss and worse!\n");

		if (flat)

			fprintf(stderr,

				"I will write value 0x%0*lx%s to address "

		                "0x%x.\n", width * 2, value,

				vmask ? " (masked)" : "", addrreg);

		else

			fprintf(stderr,

				"I will write value 0x%0*lx%s to address "

		                "0x%02x of chip with address register 0x%x\n"

		                "and data register 0x%x.\n", width * 2,

		                value, vmask ? " (masked)" : "", addr,

			        addrreg, datareg);

		fprintf(stderr, "Continue? [Y/n] ");

		fflush(stderr);

		if (!user_ack(1)) {

			fprintf(stderr, "Aborting on user request.\n");

			exit(0);

		}

	}

#ifndef __powerpc__

	if (!flat && datareg < 0x400 && addrreg < 0x400) {

		if (ioperm(datareg, 1, 1)) {

			fprintf(stderr, "Error: Could not ioperm() data "

			        "register!\n");

			exit(1);

		}

		if (ioperm(addrreg, 1, 1)) {

			fprintf(stderr, "Error: Could not ioperm() address "

		        	"register!\n");

			exit(1);

		}

	} else {

		if (iopl(3)) {

			fprintf(stderr, "Error: Could not do iopl(3)!\n");

			exit(1);

		}

	}

#endif

	if (vmask) {

		unsigned long oldvalue;

		if (flat) {

			oldvalue = inx(addrreg, width);

		} else {	

			outb(addr, addrreg);

			oldvalue = inx(datareg, width);

		}

		value = (value & vmask) | (oldvalue & ~vmask);

		if (!yes) {

			fprintf(stderr, "Old value 0x%0*lx, write mask "

				"0x%0*lx: Will write 0x%0*lx to %s "

				"0x%02x\n", width * 2, oldvalue,

				width * 2, vmask, width * 2, value,

				flat ? "address" : "register",

				flat ? addrreg : addr);

			fprintf(stderr, "Continue? [Y/n] ");

			fflush(stderr);

			if (!user_ack(1)) {

				fprintf(stderr, "Aborting on user request.\n");

				exit(0);

			}

		}

	}

	/* do the real thing */

	if (flat) {

		/* write */

		outx(value, addrreg, width);

		/* readback */

		res = inx(addrreg, width);

	} else {	

		/* write */

		outb(addr, addrreg);

		outx(value, datareg, width);

		/* readback */

		res = inx(datareg, width);

	}

	if (res != value) {

		fprintf(stderr, "Data mismatch, wrote 0x%0*lx, "

		        "read 0x%0*lx back.\n", width * 2, value,

			width * 2, res);

	}

	exit(0);

}