/* 
 * Copyright (c) 2013 Yasushi Oshima, All rights reserved.  
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY YASUSHI OSHIMA ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 */

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <unistd.h>
#include <x68k/grfioctl.h>

#include "crtmod.h"
#include "crtmodfunc.h"

static SetRegs modes[20] = {
	{ 91,  9, 17, 81, 567, 5, 40, 552, 27, 0x415 },	/* 512*512*4 in 1024*1024/Hi */
	{ 75,  3,  5, 69, 259, 2, 16, 256, 44, 0x405 },	/* 512*512*4 in 1024*1024/Lo */
	{ 45,  4,  6, 38, 567, 5, 40, 552, 27, 0x410 },	/* 256*256*4 in 1024*1024/Hi */
	{ 37,  1,  0, 32, 259, 2, 16, 256, 36, 0x400 },	/* 256*256*4 in 1024*1024/Lo */
	{ 91,  9, 17, 81, 567, 5, 40, 552, 27, 0x15 },	/* 512*512*4 in 512*512/Hi */
	{ 75,  3,  5, 69, 259, 2, 16, 256, 44, 0x05 },	/* 512*512*4 in 512*512/Lo */
	{ 45,  4,  6, 38, 567, 5, 40, 552, 27, 0x10 },	/* 256*256*4 in 512*512/Hi */
	{ 37,  1,  0, 32, 259, 2, 16, 256, 36, 0x00 },	/* 256*256*4 in 512*512/Lo */
	{ 91,  9, 17, 81, 567, 5, 40, 552, 27, 0x115 },	/* 512*512*8 in 512*512/Hi */
	{ 75,  3,  5, 69, 259, 2, 16, 256, 44, 0x105 },	/* 512*512*8 in 512*512/Lo */
	{ 45,  4,  6, 38, 567, 5, 40, 552, 27, 0x110 },	/* 256*256*8 in 512*512/Hi */
	{ 37,  1,  0, 32, 259, 2, 16, 256, 36, 0x100 },	/* 256*256*8 in 512*512/Lo */
	{ 91,  9, 17, 81, 567, 5, 40, 552, 27, 0x315 },	/* 512*512*16 in 512*512/Hi */
	{ 75,  3,  5, 69, 259, 2, 16, 256, 44, 0x305 },	/* 512*512*16 in 512*512/Lo */
	{ 45,  4,  6, 38, 567, 5, 40, 552, 27, 0x310 },	/* 256*256*16 in 512*512/Hi */
	{ 37,  1,  0, 32, 259, 2, 16, 256, 36, 0x300 },	/* 256*256*16 in 512*512/Lo */
	{137, 14, 28,124, 567, 5, 40, 552, 27, 0x416 },	/* 768*512*4 in 1024*1024/Hi */
	{137, 14, 28,124, 567, 5, 40, 552, 27, 0x416 },	/* XXX: 1024*400*4 in 1024*1024/Mi */
	{137, 14, 28,124, 567, 5, 40, 552, 27, 0x416 },	/* XXX: 1024*800*4 in 1024*1024/Mi */
	{ 99, 11, 13, 93, 524, 1, 33, 513, 27, 0x417 }	/* 640*480*4 in 1024*1024/VGA */
};


int setCrtmode(int n) {
	int grfdev;
	FbReg *regs;
	struct grfinfo gfi;
	SetRegs *sr;
	int ret;

	if ((grfdev = open ("/dev/grf1", O_RDWR, 0)) < 0 ) {
		return -1;
	}

	if (ioctl(grfdev, GRFIOCGINFO, &gfi) == -1 ) {
		close(grfdev);
                return -1;
        }

	if ( (regs = (FbReg *) mmap (0, sizeof(FbReg),
	    PROT_READ | PROT_WRITE,  MAP_FILE | MAP_SHARED,
	    grfdev, 0) ) == (FbReg *)-1 ) {
		close(grfdev);
                return -1;
	}

	if ( n < 20 ) {
		sr = &(modes[n]);
		regs->crtc.r00 = sr->r00;
		regs->crtc.r01 = sr->r01;
		regs->crtc.r02 = sr->r02;
		regs->crtc.r03 = sr->r03;
		regs->crtc.r04 = sr->r04;
		regs->crtc.r05 = sr->r05;
		regs->crtc.r06= sr->r06;
		regs->crtc.r07= sr->r07;
		regs->crtc.r08= sr->r08;
		regs->crtc.r20 = sr->r20;
		regs->videoc.r0 = ((sr->r20)>>8)&7;
		ret = 0;
	} else {
		ret = -1;
	}
	munmap(regs, sizeof(FbReg));
	close(grfdev);
	return ret;
}