/*
        Haiku S3 Savage driver adapted from the X.org Savage driver.

        Copyright (C) 1994-2000 The XFree86 Project, Inc.       All Rights Reserved.
        Copyright (c) 2003-2006, X.Org Foundation

        Copyright 2007-2008 Haiku, Inc.  All rights reserved.
        Distributed under the terms of the MIT license.

        Authors:
        Gerald Zajac 2007-2008
*/

#include "accel.h"
#include "savage.h"

#include <string.h>
#include <ddc.h>
#include <edid.h>



static status_t
GetI2CSignals(void* cookie, int* _clock, int* data)
{
        uint32 index = (uint32)(addr_t)cookie;
        uint8 value = ReadCrtcReg(index);

        *_clock = (value & 0x4) != 0;
        *data = (value & 0x8) != 0;
        return B_OK;
}


static status_t
SetI2CSignals(void* cookie, int _clock, int data)
{
        uint32 index = (uint32)(addr_t)cookie;
        uint8 value = 0x10;

        if (_clock)
                value |= 0x1;
        if (data)
                value |= 0x2;

        WriteCrtcReg(index, value);
        return B_OK;
}



bool
Savage_GetEdidInfo(edid1_info& edidInfo)
{
        // Get the EDID info and return true if successful.

        SharedInfo& si = *gInfo.sharedInfo;

        uint32 DDCPort = 0;

    switch (si.chipType) {
        case S3_SAVAGE_3D:
        case S3_SAVAGE_MX:
        case S3_SUPERSAVAGE:
        case S3_SAVAGE2000:
                DDCPort = 0xAA;
                break;

        case S3_SAVAGE4:
        case S3_PROSAVAGE:
        case S3_TWISTER:
        case S3_PROSAVAGE_DDR:
                DDCPort = 0xB1;
                break;
    }

        i2c_bus bus;
        bus.cookie = (void*)(addr_t)DDCPort;
        bus.set_signals = &SetI2CSignals;
        bus.get_signals = &GetI2CSignals;
        ddc2_init_timing(&bus);

        uint8 tmp = ReadCrtcReg(DDCPort);
        WriteCrtcReg(DDCPort, tmp | 0x13);

        bool bResult = (ddc2_read_edid1(&bus, &edidInfo, NULL, NULL) == B_OK);
        WriteCrtcReg(DDCPort, tmp);

        return bResult;
}