Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * Bootloader version of the i2c driver for the MV64x60.

 *

 * Author: Dale Farnsworth <dfarnsworth@mvista.com>

 * Maintained by: Mark A. Greer <mgreer@mvista.com>

 *

 * 2003, 2007 (c) MontaVista, Software, Inc.  This file is licensed under

 * the terms of the GNU General Public License version 2.  This program is

 * licensed "as is" without any warranty of any kind, whether express or

 * implied.

 */

#include <stdarg.h>

#include <stddef.h>

#include "types.h"

#include "elf.h"

#include "page.h"

#include "string.h"

#include "stdio.h"

#include "io.h"

#include "ops.h"

#include "mv64x60.h"

/* Register defines */

#define MV64x60_I2C_REG_SLAVE_ADDR                      0x00

#define MV64x60_I2C_REG_DATA                            0x04

#define MV64x60_I2C_REG_CONTROL                         0x08

#define MV64x60_I2C_REG_STATUS                          0x0c

#define MV64x60_I2C_REG_BAUD                            0x0c

#define MV64x60_I2C_REG_EXT_SLAVE_ADDR                  0x10

#define MV64x60_I2C_REG_SOFT_RESET                      0x1c

#define MV64x60_I2C_CONTROL_ACK                         0x04

#define MV64x60_I2C_CONTROL_IFLG                        0x08

#define MV64x60_I2C_CONTROL_STOP                        0x10

#define MV64x60_I2C_CONTROL_START                       0x20

#define MV64x60_I2C_CONTROL_TWSIEN                      0x40

#define MV64x60_I2C_CONTROL_INTEN                       0x80

#define MV64x60_I2C_STATUS_BUS_ERR                      0x00

#define MV64x60_I2C_STATUS_MAST_START                   0x08

#define MV64x60_I2C_STATUS_MAST_REPEAT_START            0x10

#define MV64x60_I2C_STATUS_MAST_WR_ADDR_ACK             0x18

#define MV64x60_I2C_STATUS_MAST_WR_ADDR_NO_ACK          0x20

#define MV64x60_I2C_STATUS_MAST_WR_ACK                  0x28

#define MV64x60_I2C_STATUS_MAST_WR_NO_ACK               0x30

#define MV64x60_I2C_STATUS_MAST_LOST_ARB                0x38

#define MV64x60_I2C_STATUS_MAST_RD_ADDR_ACK             0x40

#define MV64x60_I2C_STATUS_MAST_RD_ADDR_NO_ACK          0x48

#define MV64x60_I2C_STATUS_MAST_RD_DATA_ACK             0x50

#define MV64x60_I2C_STATUS_MAST_RD_DATA_NO_ACK          0x58

#define MV64x60_I2C_STATUS_MAST_WR_ADDR_2_ACK           0xd0

#define MV64x60_I2C_STATUS_MAST_WR_ADDR_2_NO_ACK        0xd8

#define MV64x60_I2C_STATUS_MAST_RD_ADDR_2_ACK           0xe0

#define MV64x60_I2C_STATUS_MAST_RD_ADDR_2_NO_ACK        0xe8

#define MV64x60_I2C_STATUS_NO_STATUS                    0xf8

static u8 *ctlr_base;

static int mv64x60_i2c_wait_for_status(int wanted)

{

        int i;

        int status;

        for (i=0; i<1000; i++) {

                udelay(10);

                status = in_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_STATUS))

                        & 0xff;

                if (status == wanted)

                        return status;

        }

        return -status;

}

static int mv64x60_i2c_control(int control, int status)

{

        out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);

        return mv64x60_i2c_wait_for_status(status);

}

static int mv64x60_i2c_read_byte(int control, int status)

{

        out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);

        if (mv64x60_i2c_wait_for_status(status) < 0)

                return -1;

        return in_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_DATA)) & 0xff;

}

static int mv64x60_i2c_write_byte(int data, int control, int status)

{

        out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_DATA), data & 0xff);

        out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);

        return mv64x60_i2c_wait_for_status(status);

}

int mv64x60_i2c_read(u32 devaddr, u8 *buf, u32 offset, u32 offset_size,

                 u32 count)

{

        int i;

        int data;

        int control;

        int status;

        if (ctlr_base == NULL)

                return -1;

        /* send reset */

        out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_SOFT_RESET), 0);

        out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_SLAVE_ADDR), 0);

        out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_EXT_SLAVE_ADDR), 0);

        out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_BAUD), (4 << 3) | 0x4);

        if (mv64x60_i2c_control(MV64x60_I2C_CONTROL_TWSIEN,

                                MV64x60_I2C_STATUS_NO_STATUS) < 0)

                return -1;

        /* send start */

        control = MV64x60_I2C_CONTROL_START | MV64x60_I2C_CONTROL_TWSIEN;

        status = MV64x60_I2C_STATUS_MAST_START;

        if (mv64x60_i2c_control(control, status) < 0)

                return -1;

        /* select device for writing */

        data = devaddr & ~0x1;

        control = MV64x60_I2C_CONTROL_TWSIEN;

        status = MV64x60_I2C_STATUS_MAST_WR_ADDR_ACK;

        if (mv64x60_i2c_write_byte(data, control, status) < 0)

                return -1;

        /* send offset of data */

        control = MV64x60_I2C_CONTROL_TWSIEN;

        status = MV64x60_I2C_STATUS_MAST_WR_ACK;

        if (offset_size > 1) {

                if (mv64x60_i2c_write_byte(offset >> 8, control, status) < 0)

                        return -1;

        }

        if (mv64x60_i2c_write_byte(offset, control, status) < 0)

                return -1;

        /* resend start */

        control = MV64x60_I2C_CONTROL_START | MV64x60_I2C_CONTROL_TWSIEN;

        status = MV64x60_I2C_STATUS_MAST_REPEAT_START;

        if (mv64x60_i2c_control(control, status) < 0)

                return -1;

        /* select device for reading */

        data = devaddr | 0x1;

        control = MV64x60_I2C_CONTROL_TWSIEN;

        status = MV64x60_I2C_STATUS_MAST_RD_ADDR_ACK;

        if (mv64x60_i2c_write_byte(data, control, status) < 0)

                return -1;

        /* read all but last byte of data */

        control = MV64x60_I2C_CONTROL_ACK | MV64x60_I2C_CONTROL_TWSIEN;

        status = MV64x60_I2C_STATUS_MAST_RD_DATA_ACK;

        for (i=1; i<count; i++) {

                data = mv64x60_i2c_read_byte(control, status);

                if (data < 0) {

                        printf("errors on iteration %d\n", i);

                        return -1;

                }

                *buf++ = data;

        }

        /* read last byte of data */

        control = MV64x60_I2C_CONTROL_TWSIEN;

        status = MV64x60_I2C_STATUS_MAST_RD_DATA_NO_ACK;

        data = mv64x60_i2c_read_byte(control, status);

        if (data < 0)

                return -1;

        *buf++ = data;

        /* send stop */

        control = MV64x60_I2C_CONTROL_STOP | MV64x60_I2C_CONTROL_TWSIEN;

        status = MV64x60_I2C_STATUS_NO_STATUS;

        if (mv64x60_i2c_control(control, status) < 0)

                return -1;

        return count;

}

int mv64x60_i2c_open(void)

{

        u32 v;

        void *devp;

        devp = finddevice("/mv64x60/i2c");

        if (devp == NULL)

                goto err_out;

        if (getprop(devp, "virtual-reg", &v, sizeof(v)) != sizeof(v))

                goto err_out;

        ctlr_base = (u8 *)v;

        return 0;

err_out:

        return -1;

}

void mv64x60_i2c_close(void)

{

        ctlr_base = NULL;

}