zephyr/drivers/i2c/i2c_lpc11u6x.c

383 lines
10 KiB
C

/*
* Copyright (c) 2020, Seagate Technology LLC
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT nxp_lpc11u6x_i2c
#include <zephyr/kernel.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/drivers/clock_control.h>
#include "i2c_lpc11u6x.h"
#define DEV_BASE(dev) (((struct lpc11u6x_i2c_config *)(dev->config))->base)
static void lpc11u6x_i2c_set_bus_speed(const struct lpc11u6x_i2c_config *cfg,
const struct device *clk_dev,
uint32_t speed)
{
uint32_t clk, div;
clock_control_get_rate(clk_dev, (clock_control_subsys_t) cfg->clkid,
&clk);
div = clk / speed;
cfg->base->sclh = div / 2;
cfg->base->scll = div - (div / 2);
}
static int lpc11u6x_i2c_configure(const struct device *dev,
uint32_t dev_config)
{
const struct lpc11u6x_i2c_config *cfg = dev->config;
struct lpc11u6x_i2c_data *data = dev->data;
uint32_t speed;
int ret;
uint8_t mux_selection = PINCTRL_STATE_DEFAULT;
switch (I2C_SPEED_GET(dev_config)) {
case I2C_SPEED_STANDARD:
speed = 100000;
break;
case I2C_SPEED_FAST:
speed = 400000;
break;
case I2C_SPEED_FAST_PLUS:
mux_selection = PINCTRL_STATE_FAST_PLUS;
speed = 1000000;
break;
case I2C_SPEED_HIGH:
case I2C_SPEED_ULTRA:
return -ENOTSUP;
default:
return -EINVAL;
}
if (dev_config & I2C_ADDR_10_BITS) {
return -ENOTSUP;
}
k_mutex_lock(&data->mutex, K_FOREVER);
lpc11u6x_i2c_set_bus_speed(cfg, cfg->clock_dev, speed);
ret = pinctrl_apply_state(cfg->pincfg, mux_selection);
if (ret) {
k_mutex_unlock(&data->mutex);
return ret;
}
k_mutex_unlock(&data->mutex);
return 0;
}
static int lpc11u6x_i2c_transfer(const struct device *dev,
struct i2c_msg *msgs,
uint8_t num_msgs, uint16_t addr)
{
const struct lpc11u6x_i2c_config *cfg = dev->config;
struct lpc11u6x_i2c_data *data = dev->data;
int ret = 0;
if (!num_msgs) {
return 0;
}
k_mutex_lock(&data->mutex, K_FOREVER);
data->transfer.msgs = msgs;
data->transfer.curr_buf = msgs->buf;
data->transfer.curr_len = msgs->len;
data->transfer.nr_msgs = num_msgs;
data->transfer.addr = addr;
/* Reset all control bits */
cfg->base->con_clr = LPC11U6X_I2C_CONTROL_SI |
LPC11U6X_I2C_CONTROL_STOP | LPC11U6X_I2C_CONTROL_START;
/* Send start and wait for completion */
data->transfer.status = LPC11U6X_I2C_STATUS_BUSY;
cfg->base->con_set = LPC11U6X_I2C_CONTROL_START;
k_sem_take(&data->completion, K_FOREVER);
if (data->transfer.status != LPC11U6X_I2C_STATUS_OK) {
ret = -EIO;
}
data->transfer.status = LPC11U6X_I2C_STATUS_INACTIVE;
/* If a slave is registered, put the controller in slave mode */
if (data->slave) {
cfg->base->con_set = LPC11U6X_I2C_CONTROL_AA;
}
k_mutex_unlock(&data->mutex);
return ret;
}
static int lpc11u6x_i2c_slave_register(const struct device *dev,
struct i2c_target_config *cfg)
{
const struct lpc11u6x_i2c_config *dev_cfg = dev->config;
struct lpc11u6x_i2c_data *data = dev->data;
int ret = 0;
if (!cfg) {
return -EINVAL;
}
if (cfg->flags & I2C_TARGET_FLAGS_ADDR_10_BITS) {
return -ENOTSUP;
}
k_mutex_lock(&data->mutex, K_FOREVER);
if (data->slave) {
ret = -EBUSY;
goto exit;
}
data->slave = cfg;
/* Configure controller to act as slave */
dev_cfg->base->addr0 = (cfg->address << 1);
dev_cfg->base->con_clr = LPC11U6X_I2C_CONTROL_START |
LPC11U6X_I2C_CONTROL_STOP | LPC11U6X_I2C_CONTROL_SI;
dev_cfg->base->con_set = LPC11U6X_I2C_CONTROL_AA;
exit:
k_mutex_unlock(&data->mutex);
return ret;
}
static int lpc11u6x_i2c_slave_unregister(const struct device *dev,
struct i2c_target_config *cfg)
{
const struct lpc11u6x_i2c_config *dev_cfg = dev->config;
struct lpc11u6x_i2c_data *data = dev->data;
if (!cfg) {
return -EINVAL;
}
if (data->slave != cfg) {
return -EINVAL;
}
k_mutex_lock(&data->mutex, K_FOREVER);
data->slave = NULL;
dev_cfg->base->con_clr = LPC11U6X_I2C_CONTROL_AA;
k_mutex_unlock(&data->mutex);
return 0;
}
static void lpc11u6x_i2c_isr(const struct device *dev)
{
struct lpc11u6x_i2c_data *data = dev->data;
struct lpc11u6x_i2c_regs *i2c = DEV_BASE(dev);
struct lpc11u6x_i2c_current_transfer *transfer = &data->transfer;
uint32_t clear = LPC11U6X_I2C_CONTROL_SI;
uint32_t set = 0;
uint8_t val;
switch (i2c->stat) {
/* Master TX states */
case LPC11U6X_I2C_MASTER_TX_START:
case LPC11U6X_I2C_MASTER_TX_RESTART:
i2c->dat = (transfer->addr << 1) |
(transfer->msgs->flags & I2C_MSG_READ);
clear |= LPC11U6X_I2C_CONTROL_START;
transfer->curr_buf = transfer->msgs->buf;
transfer->curr_len = transfer->msgs->len;
break;
case LPC11U6X_I2C_MASTER_TX_ADR_ACK:
case LPC11U6X_I2C_MASTER_TX_DAT_ACK:
if (!transfer->curr_len) {
transfer->msgs++;
transfer->nr_msgs--;
if (!transfer->nr_msgs) {
transfer->status = LPC11U6X_I2C_STATUS_OK;
set |= LPC11U6X_I2C_CONTROL_STOP;
} else {
set |= LPC11U6X_I2C_CONTROL_START;
}
} else {
i2c->dat = transfer->curr_buf[0];
transfer->curr_buf++;
transfer->curr_len--;
}
break;
/* Master RX states */
case LPC11U6X_I2C_MASTER_RX_DAT_NACK:
transfer->msgs++;
transfer->nr_msgs--;
set |= (transfer->nr_msgs ? LPC11U6X_I2C_CONTROL_START :
LPC11U6X_I2C_CONTROL_STOP);
if (!transfer->nr_msgs) {
transfer->status = LPC11U6X_I2C_STATUS_OK;
}
__fallthrough;
case LPC11U6X_I2C_MASTER_RX_DAT_ACK:
transfer->curr_buf[0] = i2c->dat;
transfer->curr_buf++;
transfer->curr_len--;
__fallthrough;
case LPC11U6X_I2C_MASTER_RX_ADR_ACK:
if (transfer->curr_len <= 1) {
clear |= LPC11U6X_I2C_CONTROL_AA;
} else {
set |= LPC11U6X_I2C_CONTROL_AA;
}
break;
/* Slave States */
case LPC11U6X_I2C_SLAVE_RX_ADR_ACK:
case LPC11U6X_I2C_SLAVE_RX_ARB_LOST_ADR_ACK:
case LPC11U6X_I2C_SLAVE_RX_GC_ACK:
case LPC11U6X_I2C_SLAVE_RX_ARB_LOST_GC_ACK:
if (data->slave->callbacks->write_requested(data->slave)) {
clear |= LPC11U6X_I2C_CONTROL_AA;
}
break;
case LPC11U6X_I2C_SLAVE_RX_DAT_ACK:
case LPC11U6X_I2C_SLAVE_RX_GC_DAT_ACK:
val = i2c->dat;
if (data->slave->callbacks->write_received(data->slave, val)) {
clear |= LPC11U6X_I2C_CONTROL_AA;
}
break;
case LPC11U6X_I2C_SLAVE_RX_DAT_NACK:
case LPC11U6X_I2C_SLAVE_RX_GC_DAT_NACK:
val = i2c->dat;
data->slave->callbacks->write_received(data->slave, val);
data->slave->callbacks->stop(data->slave);
set |= LPC11U6X_I2C_CONTROL_AA;
break;
case LPC11U6X_I2C_SLAVE_RX_STOP:
data->slave->callbacks->stop(data->slave);
set |= LPC11U6X_I2C_CONTROL_AA;
break;
case LPC11U6X_I2C_SLAVE_TX_ADR_ACK:
case LPC11U6X_I2C_SLAVE_TX_ARB_LOST_ADR_ACK:
if (data->slave->callbacks->read_requested(data->slave, &val)) {
clear |= LPC11U6X_I2C_CONTROL_AA;
}
i2c->dat = val;
break;
case LPC11U6X_I2C_SLAVE_TX_DAT_ACK:
if (data->slave->callbacks->read_processed(data->slave, &val)) {
clear |= LPC11U6X_I2C_CONTROL_AA;
}
i2c->dat = val;
break;
case LPC11U6X_I2C_SLAVE_TX_DAT_NACK:
case LPC11U6X_I2C_SLAVE_TX_LAST_BYTE:
data->slave->callbacks->stop(data->slave);
set |= LPC11U6X_I2C_CONTROL_AA;
break;
/* Error cases */
case LPC11U6X_I2C_MASTER_TX_ADR_NACK:
case LPC11U6X_I2C_MASTER_RX_ADR_NACK:
case LPC11U6X_I2C_MASTER_TX_DAT_NACK:
case LPC11U6X_I2C_MASTER_TX_ARB_LOST:
transfer->status = LPC11U6X_I2C_STATUS_FAIL;
set = LPC11U6X_I2C_CONTROL_STOP;
break;
default:
set = LPC11U6X_I2C_CONTROL_STOP;
break;
}
i2c->con_clr = clear;
i2c->con_set = set;
if ((transfer->status != LPC11U6X_I2C_STATUS_BUSY) &&
(transfer->status != LPC11U6X_I2C_STATUS_INACTIVE)) {
k_sem_give(&data->completion);
}
}
static int lpc11u6x_i2c_init(const struct device *dev)
{
const struct lpc11u6x_i2c_config *cfg = dev->config;
struct lpc11u6x_i2c_data *data = dev->data;
int err;
err = pinctrl_apply_state(cfg->pincfg, PINCTRL_STATE_DEFAULT);
if (err) {
return err;
}
if (!device_is_ready(cfg->clock_dev)) {
return -ENODEV;
}
/* Configure clock and de-assert reset for I2Cx */
clock_control_on(cfg->clock_dev, (clock_control_subsys_t) cfg->clkid);
/* Configure bus speed. Default is 100KHz */
lpc11u6x_i2c_set_bus_speed(cfg, cfg->clock_dev, 100000);
/* Clear all control bytes and enable I2C interface */
cfg->base->con_clr = LPC11U6X_I2C_CONTROL_AA | LPC11U6X_I2C_CONTROL_SI |
LPC11U6X_I2C_CONTROL_START | LPC11U6X_I2C_CONTROL_I2C_EN;
cfg->base->con_set = LPC11U6X_I2C_CONTROL_I2C_EN;
/* Initialize mutex and semaphore */
k_mutex_init(&data->mutex);
k_sem_init(&data->completion, 0, 1);
data->transfer.status = LPC11U6X_I2C_STATUS_INACTIVE;
/* Configure IRQ */
cfg->irq_config_func(dev);
return 0;
}
static const struct i2c_driver_api i2c_api = {
.configure = lpc11u6x_i2c_configure,
.transfer = lpc11u6x_i2c_transfer,
.target_register = lpc11u6x_i2c_slave_register,
.target_unregister = lpc11u6x_i2c_slave_unregister,
};
#define LPC11U6X_I2C_INIT(idx) \
\
static void lpc11u6x_i2c_isr_config_##idx(const struct device *dev); \
\
PINCTRL_DT_INST_DEFINE(idx); \
\
static const struct lpc11u6x_i2c_config i2c_cfg_##idx = { \
.base = \
(struct lpc11u6x_i2c_regs *) DT_INST_REG_ADDR(idx), \
.clock_dev = DEVICE_DT_GET(DT_INST_CLOCKS_CTLR(idx)), \
.irq_config_func = lpc11u6x_i2c_isr_config_##idx, \
.pincfg = PINCTRL_DT_INST_DEV_CONFIG_GET(idx), \
.clkid = DT_INST_PHA_BY_IDX(idx, clocks, 0, clkid), \
}; \
\
static struct lpc11u6x_i2c_data i2c_data_##idx; \
\
I2C_DEVICE_DT_INST_DEFINE(idx, \
lpc11u6x_i2c_init, \
NULL, \
&i2c_data_##idx, &i2c_cfg_##idx, \
PRE_KERNEL_1, CONFIG_I2C_INIT_PRIORITY, \
&i2c_api); \
\
static void lpc11u6x_i2c_isr_config_##idx(const struct device *dev) \
{ \
IRQ_CONNECT(DT_INST_IRQN(idx), \
DT_INST_IRQ(idx, priority), \
lpc11u6x_i2c_isr, DEVICE_DT_INST_GET(idx), 0); \
\
irq_enable(DT_INST_IRQN(idx)); \
}
DT_INST_FOREACH_STATUS_OKAY(LPC11U6X_I2C_INIT);