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//

//

//    Copyright 2010 TheSeven

//

//

//    This file is part of emCORE.

//

//    emCORE 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.

//

//    emCORE 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 emCORE.  If not, see <http://www.gnu.org/licenses/>.

//

//

#include "global.h"

#include "i2c.h"

#include "thread.h"

#include "s5l8702.h"

#include "clockgates.h"

static struct mutex i2cmutex;

static void i2c_on(int bus)

{

    /* enable I2C clock */

    clockgate_enable(CLOCKGATE_I2C(bus), true);

    IICCON(bus) = (1 << 7) | /* ACK_GEN */

                  (0 << 6) | /* CLKSEL = PCLK/16 */

                  (1 << 5) | /* INT_EN */

                  (1 << 4) | /* IRQ clear */

                  (7 << 0);  /* CK_REG */

    /* serial output on */

    IICSTAT(bus) = (1 << 4);

}

static void i2c_off(int bus)

{

    /* serial output off */

    IICSTAT(bus) = 0;

    /* disable I2C clock */

    clockgate_enable(CLOCKGATE_I2C(bus), false);

}

void i2c_init()

{

    mutex_init(&i2cmutex);

}

void i2c_send(uint32_t bus, uint32_t device, uint32_t address, const uint8_t* data, uint32_t length)

{

    mutex_lock(&i2cmutex, TIMEOUT_BLOCK);

	i2c_on(bus);

    while (IIC10(bus));

    IICDS(bus) = device & ~1;

    while (IIC10(bus));

    IICSTAT(bus) = 0xF0;

    while (IIC10(bus));

    IICCON(bus) = 0xB7;

    while (IIC10(bus));

    while ((IICCON(bus) & 0x10) == 0) yield();

    if (address >= 0)

    {

        /* write address */

        while (IIC10(bus));

        IICDS(bus) = address;

        while (IIC10(bus));

        IICCON(bus) = 0xB7;

        while (IIC10(bus));

        while ((IICCON(bus) & 0x10) == 0) yield();

    }

    /* write data */

    while (length--)

    {

        while (IIC10(bus));

        IICDS(bus) = *data++;

        while (IIC10(bus));

        IICCON(bus) = 0xB7;

        while (IIC10(bus));

        while ((IICCON(bus) & 0x10) == 0) yield();

    }

    /* STOP */

    while (IIC10(bus));

    IICSTAT(bus) = 0xD0;

    while (IIC10(bus));

    IICCON(bus) = 0xB7;

    while ((IICSTAT(bus) & (1 << 5)) != 0) yield();

	i2c_off(bus);

    mutex_unlock(&i2cmutex);

}

void i2c_recv(uint32_t bus, uint32_t device, uint32_t address, uint8_t* data, uint32_t length)

{

    mutex_lock(&i2cmutex, TIMEOUT_BLOCK);

	i2c_on(bus);

    if (address >= 0)

    {

        /* START */

        while (IIC10(bus));

        IICDS(bus) = device & ~1;

        while (IIC10(bus));

        IICSTAT(bus) = 0xF0;

        while (IIC10(bus));

        IICCON(bus) = 0xB7;

        while (IIC10(bus));

        while ((IICCON(bus) & 0x10) == 0) yield();

        /* write address */

        while (IIC10(bus));

        IICDS(bus) = address;

        while (IIC10(bus));

        IICCON(bus) = 0xB7;

        while (IIC10(bus));

        while ((IICCON(bus) & 0x10) == 0) yield();

    }

    /* (repeated) START */

    while (IIC10(bus));

    IICDS(bus) = device | 1;

    while (IIC10(bus));

    IICSTAT(bus) = 0xB0;

    while (IIC10(bus));

    IICCON(bus) = 0xB7;

    while (IIC10(bus));

    while ((IICCON(bus) & 0x10) == 0) yield();

    while (length--)

    {

        while (IIC10(bus));

        IICCON(bus) = (length == 0) ? 0x37 : 0xB7; /* NACK or ACK */

        while (IIC10(bus));

        while ((IICCON(bus) & 0x10) == 0) yield();

        *data++ = IICDS(bus);

    }

    /* STOP */

    while (IIC10(bus));

    IICSTAT(bus) = 0x90;

    while (IIC10(bus));

    IICCON(bus) = 0xB7;

    while (IIC10(bus));

    while ((IICSTAT(bus) & (1 << 5)) != 0) yield();

	i2c_off(bus);

    mutex_unlock(&i2cmutex);

}

void i2c_sendbyte(uint32_t bus, uint32_t device, uint32_t address, uint32_t data)

{

    uint8_t buf[1];

    buf[0] = data;

    i2c_send(bus, device, address, buf, 1);

}

uint8_t i2c_recvbyte(uint32_t bus, uint32_t device, uint32_t address)

{

    uint8_t buf[1];

    i2c_recv(bus, device, address, buf, 1);

    return buf[0];

}