leandrof/u-boot
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
01ec99d969
u-boot/drivers/i2c/mvtwsi.c
Albert Aribaud 01ec99d969 i2c: rename kirkwood_i2c to mvtwsi 
This driver is not kirkwood-specific and can also be used
e.g. by orion5x. Rename to a SoC-neutral name.

Signed-off-by: Albert Aribaud <albert.aribaud@free.fr>
Acked-by: Prafulla Wadaskar<prafulla@marvell.com>
Acked-by: Heiko Schocher<hs@denx.de>
2010-08-30 14:10:23 +02:00

497 lines
13 KiB
C
Raw Blame History

/*
* Driver for the i2c controller on the Marvell line of host bridges
* (e.g, gt642[46]0, mv643[46]0, mv644[46]0, Orion SoC family),
* and Kirkwood family.
*
* Based on:
* Author: Mark A. Greer <mgreer@mvista.com>
* 2005 (c) MontaVista, Software, Inc.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*
* ported from Linux to u-boot
* (C) Copyright 2009
* Heiko Schocher, DENX Software Engineering, hs@denx.de.
*/
#include <common.h>
#include <i2c.h>
#include <asm/arch/kirkwood.h>
#include <asm/errno.h>
#include <asm/io.h>
DECLARE_GLOBAL_DATA_PTR;
static unsigned int i2c_bus_num __attribute__ ((section (".data"))) = 0;
#if defined(CONFIG_I2C_MUX)
static unsigned int i2c_bus_num_mux __attribute__ ((section ("data"))) = 0;
#endif
/* Register defines */
#define KW_I2C_REG_SLAVE_ADDR 0x00
#define KW_I2C_REG_DATA 0x04
#define KW_I2C_REG_CONTROL 0x08
#define KW_I2C_REG_STATUS 0x0c
#define KW_I2C_REG_BAUD 0x0c
#define KW_I2C_REG_EXT_SLAVE_ADDR 0x10
#define KW_I2C_REG_SOFT_RESET 0x1c
#define KW_I2C_REG_CONTROL_ACK 0x00000004
#define KW_I2C_REG_CONTROL_IFLG 0x00000008
#define KW_I2C_REG_CONTROL_STOP 0x00000010
#define KW_I2C_REG_CONTROL_START 0x00000020
#define KW_I2C_REG_CONTROL_TWSIEN 0x00000040
#define KW_I2C_REG_CONTROL_INTEN 0x00000080
/* Ctlr status values */
#define KW_I2C_STATUS_BUS_ERR 0x00
#define KW_I2C_STATUS_MAST_START 0x08
#define KW_I2C_STATUS_MAST_REPEAT_START 0x10
#define KW_I2C_STATUS_MAST_WR_ADDR_ACK 0x18
#define KW_I2C_STATUS_MAST_WR_ADDR_NO_ACK 0x20
#define KW_I2C_STATUS_MAST_WR_ACK 0x28
#define KW_I2C_STATUS_MAST_WR_NO_ACK 0x30
#define KW_I2C_STATUS_MAST_LOST_ARB 0x38
#define KW_I2C_STATUS_MAST_RD_ADDR_ACK 0x40
#define KW_I2C_STATUS_MAST_RD_ADDR_NO_ACK 0x48
#define KW_I2C_STATUS_MAST_RD_DATA_ACK 0x50
#define KW_I2C_STATUS_MAST_RD_DATA_NO_ACK 0x58
#define KW_I2C_STATUS_MAST_WR_ADDR_2_ACK 0xd0
#define KW_I2C_STATUS_MAST_WR_ADDR_2_NO_ACK 0xd8
#define KW_I2C_STATUS_MAST_RD_ADDR_2_ACK 0xe0
#define KW_I2C_STATUS_MAST_RD_ADDR_2_NO_ACK 0xe8
#define KW_I2C_STATUS_NO_STATUS 0xf8
/* Driver states */
enum {
KW_I2C_STATE_INVALID,
KW_I2C_STATE_IDLE,
KW_I2C_STATE_WAITING_FOR_START_COND,
KW_I2C_STATE_WAITING_FOR_ADDR_1_ACK,
KW_I2C_STATE_WAITING_FOR_ADDR_2_ACK,
KW_I2C_STATE_WAITING_FOR_SLAVE_ACK,
KW_I2C_STATE_WAITING_FOR_SLAVE_DATA,
};
/* Driver actions */
enum {
KW_I2C_ACTION_INVALID,
KW_I2C_ACTION_CONTINUE,
KW_I2C_ACTION_SEND_START,
KW_I2C_ACTION_SEND_ADDR_1,
KW_I2C_ACTION_SEND_ADDR_2,
KW_I2C_ACTION_SEND_DATA,
KW_I2C_ACTION_RCV_DATA,
KW_I2C_ACTION_RCV_DATA_STOP,
KW_I2C_ACTION_SEND_STOP,
};
/* defines to get compatible with Linux driver */
#define IRQ_NONE 0x0
#define IRQ_HANDLED 0x01
#define I2C_M_TEN 0x01
#define I2C_M_RD 0x02
#define I2C_M_REV_DIR_ADDR 0x04;
struct i2c_msg {
u32 addr;
u32 flags;
u8 *buf;
u32 len;
};
struct kirkwood_i2c_data {
int irq;
u32 state;
u32 action;
u32 aborting;
u32 cntl_bits;
void *reg_base;
u32 reg_base_p;
u32 reg_size;
u32 addr1;
u32 addr2;
u32 bytes_left;
u32 byte_posn;
u32 block;
int rc;
u32 freq_m;
u32 freq_n;
struct i2c_msg *msg;
};
static struct kirkwood_i2c_data __drv_data __attribute__ ((section (".data")));
static struct kirkwood_i2c_data *drv_data = &__drv_data;
static struct i2c_msg __i2c_msg __attribute__ ((section (".data")));
static struct i2c_msg *kirkwood_i2c_msg = &__i2c_msg;
/*
*****************************************************************************
*
* Finite State Machine & Interrupt Routines
*
*****************************************************************************
*/
static inline int abs(int n)
{
if(n >= 0)
return n;
else
return n * -1;
}
static void kirkwood_calculate_speed(int speed)
{
int calcspeed;
int diff;
int best_diff = CONFIG_SYS_TCLK;
int best_speed = 0;
int m, n;
int tmp[8] = {2, 4, 8, 16, 32, 64, 128, 256};
for (n = 0; n < 8; n++) {
for (m = 0; m < 16; m++) {
calcspeed = CONFIG_SYS_TCLK / (10 * (m + 1) * tmp[n]);
diff = abs((speed - calcspeed));
if ( diff < best_diff) {
best_diff = diff;
best_speed = calcspeed;
drv_data->freq_m = m;
drv_data->freq_n = n;
}
}
}
}
/* Reset hardware and initialize FSM */
static void
kirkwood_i2c_hw_init(int speed, int slaveadd)
{
drv_data->state = KW_I2C_STATE_IDLE;
kirkwood_calculate_speed(speed);
writel(0, CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_SOFT_RESET);
writel((((drv_data->freq_m & 0xf) << 3) | (drv_data->freq_n & 0x7)),
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_BAUD);
writel(slaveadd, CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_SLAVE_ADDR);
writel(0, CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_EXT_SLAVE_ADDR);
writel(KW_I2C_REG_CONTROL_TWSIEN | KW_I2C_REG_CONTROL_STOP,
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
}
static void
kirkwood_i2c_fsm(u32 status)
{
/*
* If state is idle, then this is likely the remnants of an old
* operation that driver has given up on or the user has killed.
* If so, issue the stop condition and go to idle.
*/
if (drv_data->state == KW_I2C_STATE_IDLE) {
drv_data->action = KW_I2C_ACTION_SEND_STOP;
return;
}
/* The status from the ctlr [mostly] tells us what to do next */
switch (status) {
/* Start condition interrupt */
case KW_I2C_STATUS_MAST_START: /* 0x08 */
case KW_I2C_STATUS_MAST_REPEAT_START: /* 0x10 */
drv_data->action = KW_I2C_ACTION_SEND_ADDR_1;
drv_data->state = KW_I2C_STATE_WAITING_FOR_ADDR_1_ACK;
break;
/* Performing a write */
case KW_I2C_STATUS_MAST_WR_ADDR_ACK: /* 0x18 */
if (drv_data->msg->flags & I2C_M_TEN) {
drv_data->action = KW_I2C_ACTION_SEND_ADDR_2;
drv_data->state =
KW_I2C_STATE_WAITING_FOR_ADDR_2_ACK;
break;
}
/* FALLTHRU */
case KW_I2C_STATUS_MAST_WR_ADDR_2_ACK: /* 0xd0 */
case KW_I2C_STATUS_MAST_WR_ACK: /* 0x28 */
if ((drv_data->bytes_left == 0)
|| (drv_data->aborting
&& (drv_data->byte_posn != 0))) {
drv_data->action = KW_I2C_ACTION_SEND_STOP;
drv_data->state = KW_I2C_STATE_IDLE;
} else {
drv_data->action = KW_I2C_ACTION_SEND_DATA;
drv_data->state =
KW_I2C_STATE_WAITING_FOR_SLAVE_ACK;
drv_data->bytes_left--;
}
break;
/* Performing a read */
case KW_I2C_STATUS_MAST_RD_ADDR_ACK: /* 40 */
if (drv_data->msg->flags & I2C_M_TEN) {
drv_data->action = KW_I2C_ACTION_SEND_ADDR_2;
drv_data->state =
KW_I2C_STATE_WAITING_FOR_ADDR_2_ACK;
break;
}
/* FALLTHRU */
case KW_I2C_STATUS_MAST_RD_ADDR_2_ACK: /* 0xe0 */
if (drv_data->bytes_left == 0) {
drv_data->action = KW_I2C_ACTION_SEND_STOP;
drv_data->state = KW_I2C_STATE_IDLE;
break;
}
/* FALLTHRU */
case KW_I2C_STATUS_MAST_RD_DATA_ACK: /* 0x50 */
if (status != KW_I2C_STATUS_MAST_RD_DATA_ACK)
drv_data->action = KW_I2C_ACTION_CONTINUE;
else {
drv_data->action = KW_I2C_ACTION_RCV_DATA;
drv_data->bytes_left--;
}
drv_data->state = KW_I2C_STATE_WAITING_FOR_SLAVE_DATA;
if ((drv_data->bytes_left == 1) || drv_data->aborting)
drv_data->cntl_bits &= ~KW_I2C_REG_CONTROL_ACK;
break;
case KW_I2C_STATUS_MAST_RD_DATA_NO_ACK: /* 0x58 */
drv_data->action = KW_I2C_ACTION_RCV_DATA_STOP;
drv_data->state = KW_I2C_STATE_IDLE;
break;
case KW_I2C_STATUS_MAST_WR_ADDR_NO_ACK: /* 0x20 */
case KW_I2C_STATUS_MAST_WR_NO_ACK: /* 30 */
case KW_I2C_STATUS_MAST_RD_ADDR_NO_ACK: /* 48 */
/* Doesn't seem to be a device at other end */
drv_data->action = KW_I2C_ACTION_SEND_STOP;
drv_data->state = KW_I2C_STATE_IDLE;
drv_data->rc = -ENODEV;
break;
default:
printf("kirkwood_i2c_fsm: Ctlr Error -- state: 0x%x, "
"status: 0x%x, addr: 0x%x, flags: 0x%x\n",
drv_data->state, status, drv_data->msg->addr,
drv_data->msg->flags);
drv_data->action = KW_I2C_ACTION_SEND_STOP;
kirkwood_i2c_hw_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
drv_data->rc = -EIO;
}
}
static void
kirkwood_i2c_do_action(void)
{
switch(drv_data->action) {
case KW_I2C_ACTION_CONTINUE:
writel(drv_data->cntl_bits,
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
break;
case KW_I2C_ACTION_SEND_START:
writel(drv_data->cntl_bits | KW_I2C_REG_CONTROL_START,
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
break;
case KW_I2C_ACTION_SEND_ADDR_1:
writel(drv_data->addr1,
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_DATA);
writel(drv_data->cntl_bits,
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
break;
case KW_I2C_ACTION_SEND_ADDR_2:
writel(drv_data->addr2,
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_DATA);
writel(drv_data->cntl_bits,
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
break;
case KW_I2C_ACTION_SEND_DATA:
writel(drv_data->msg->buf[drv_data->byte_posn++],
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_DATA);
writel(drv_data->cntl_bits,
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
break;
case KW_I2C_ACTION_RCV_DATA:
drv_data->msg->buf[drv_data->byte_posn++] =
readl(CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_DATA);
writel(drv_data->cntl_bits,
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
break;
case KW_I2C_ACTION_RCV_DATA_STOP:
drv_data->msg->buf[drv_data->byte_posn++] =
readl(CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_DATA);
drv_data->cntl_bits &= ~KW_I2C_REG_CONTROL_INTEN;
writel(drv_data->cntl_bits | KW_I2C_REG_CONTROL_STOP,
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
drv_data->block = 0;
break;
case KW_I2C_ACTION_INVALID:
default:
printf("kirkwood_i2c_do_action: Invalid action: %d\n",
drv_data->action);
drv_data->rc = -EIO;
/* FALLTHRU */
case KW_I2C_ACTION_SEND_STOP:
drv_data->cntl_bits &= ~KW_I2C_REG_CONTROL_INTEN;
writel(drv_data->cntl_bits | KW_I2C_REG_CONTROL_STOP,
CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
drv_data->block = 0;
break;
}
}
static int
kirkwood_i2c_intr(void)
{
u32 status;
u32 ctrl;
int rc = IRQ_NONE;
ctrl = readl(CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
while ((ctrl & KW_I2C_REG_CONTROL_IFLG) &&
(drv_data->rc == 0)) {
status = readl(CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_STATUS);
kirkwood_i2c_fsm(status);
kirkwood_i2c_do_action();
rc = IRQ_HANDLED;
ctrl = readl(CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
udelay(1000);
}
return rc;
}
static void
kirkwood_i2c_doio(struct i2c_msg *msg)
{
int ret;
while ((drv_data->rc == 0) && (drv_data->state != KW_I2C_STATE_IDLE)) {
/* poll Status register */
ret = kirkwood_i2c_intr();
if (ret == IRQ_NONE)
udelay(10);
}
}
static void
kirkwood_i2c_prepare_for_io(struct i2c_msg *msg)
{
u32 dir = 0;
drv_data->msg = msg;
drv_data->byte_posn = 0;
drv_data->bytes_left = msg->len;
drv_data->aborting = 0;
drv_data->rc = 0;
/* in u-boot we use no IRQs */
drv_data->cntl_bits = KW_I2C_REG_CONTROL_ACK | KW_I2C_REG_CONTROL_TWSIEN;
if (msg->flags & I2C_M_RD)
dir = 1;
if (msg->flags & I2C_M_TEN) {
drv_data->addr1 = 0xf0 | (((u32)msg->addr & 0x300) >> 7) | dir;
drv_data->addr2 = (u32)msg->addr & 0xff;
} else {
drv_data->addr1 = ((u32)msg->addr & 0x7f) << 1 | dir;
drv_data->addr2 = 0;
}
/* OK, no start it (from kirkwood_i2c_execute_msg())*/
drv_data->action = KW_I2C_ACTION_SEND_START;
drv_data->state = KW_I2C_STATE_WAITING_FOR_START_COND;
drv_data->block = 1;
kirkwood_i2c_do_action();
}
void
i2c_init(int speed, int slaveadd)
{
kirkwood_i2c_hw_init(speed, slaveadd);
}
int
i2c_read(u8 dev, uint addr, int alen, u8 *data, int length)
{
kirkwood_i2c_msg->buf = data;
kirkwood_i2c_msg->len = length;
kirkwood_i2c_msg->addr = dev;
kirkwood_i2c_msg->flags = I2C_M_RD;
kirkwood_i2c_prepare_for_io(kirkwood_i2c_msg);
kirkwood_i2c_doio(kirkwood_i2c_msg);
return drv_data->rc;
}
int
i2c_write(u8 dev, uint addr, int alen, u8 *data, int length)
{
kirkwood_i2c_msg->buf = data;
kirkwood_i2c_msg->len = length;
kirkwood_i2c_msg->addr = dev;
kirkwood_i2c_msg->flags = 0;
kirkwood_i2c_prepare_for_io(kirkwood_i2c_msg);
kirkwood_i2c_doio(kirkwood_i2c_msg);
return drv_data->rc;
}
int
i2c_probe(uchar chip)
{
return i2c_read(chip, 0, 0, NULL, 0);
}
int i2c_set_bus_num(unsigned int bus)
{
#if defined(CONFIG_I2C_MUX)
if (bus < CONFIG_SYS_MAX_I2C_BUS) {
i2c_bus_num = bus;
} else {
int ret;
ret = i2x_mux_select_mux(bus);
if (ret)
return ret;
i2c_bus_num = 0;
}
i2c_bus_num_mux = bus;
#else
if (bus > 0) {
return -1;
}
i2c_bus_num = bus;
#endif
return 0;
}
unsigned int i2c_get_bus_num(void)
{
#if defined(CONFIG_I2C_MUX)
return i2c_bus_num_mux;
#else
return i2c_bus_num;
#endif
}
Reference in New Issue View Git Blame Copy Permalink