kernel-ark/arch/powerpc/boot/mv64x60_i2c.c
Scott Wood 3ee9b7abaf [POWERPC] bootwrapper: Declare udelay() in ops.h
Declarations in various users are removed.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-08-22 15:21:49 +10:00

205 lines
5.5 KiB
C

/*
* 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;
}