blob: f49521dc4e5db03b59a235a8f3c82be3c8bdb38a [file] [log] [blame]
/*
* Copyright (c) 2018 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT altr_nios2_i2c
#include <errno.h>
#include <drivers/i2c.h>
#include <soc.h>
#include <sys/util.h>
#include <altera_common.h>
#include "altera_avalon_i2c.h"
#define LOG_LEVEL CONFIG_I2C_LOG_LEVEL
#include <logging/log.h>
LOG_MODULE_REGISTER(i2c_nios2);
#define NIOS2_I2C_TIMEOUT_USEC 1000
#define DEV_CFG(dev) \
((struct i2c_nios2_config *)(dev)->config)
struct i2c_nios2_config {
ALT_AVALON_I2C_DEV_t i2c_dev;
IRQ_DATA_t irq_data;
struct k_sem sem_lock;
};
static int i2c_nios2_configure(const struct device *dev, uint32_t dev_config)
{
struct i2c_nios2_config *config = DEV_CFG(dev);
int32_t rc = 0;
k_sem_take(&config->sem_lock, K_FOREVER);
if (!(I2C_MODE_MASTER & dev_config)) {
LOG_ERR("i2c config mode error\n");
rc = -EINVAL;
goto i2c_cfg_err;
}
if (I2C_ADDR_10_BITS & dev_config) {
LOG_ERR("i2c config addressing error\n");
rc = -EINVAL;
goto i2c_cfg_err;
}
if (I2C_SPEED_GET(dev_config) != I2C_SPEED_STANDARD) {
LOG_ERR("i2c config speed error\n");
rc = -EINVAL;
goto i2c_cfg_err;
}
alt_avalon_i2c_init(&config->i2c_dev);
i2c_cfg_err:
k_sem_give(&config->sem_lock);
return rc;
}
static int i2c_nios2_transfer(const struct device *dev, struct i2c_msg *msgs,
uint8_t num_msgs, uint16_t addr)
{
struct i2c_nios2_config *config = DEV_CFG(dev);
ALT_AVALON_I2C_STATUS_CODE status;
uint32_t restart, stop;
int32_t i, timeout, rc = 0;
k_sem_take(&config->sem_lock, K_FOREVER);
/* register the optional interrupt callback */
alt_avalon_i2c_register_optional_irq_handler(
&config->i2c_dev, &config->irq_data);
/* Iterate over all the messages */
for (i = 0; i < num_msgs; i++) {
/* convert restart flag */
if (msgs->flags & I2C_MSG_RESTART) {
restart = ALT_AVALON_I2C_RESTART;
} else {
restart = ALT_AVALON_I2C_NO_RESTART;
}
/* convert stop flag */
if (msgs->flags & I2C_MSG_STOP) {
stop = ALT_AVALON_I2C_STOP;
} else {
stop = ALT_AVALON_I2C_NO_STOP;
}
/* Set the slave device address */
alt_avalon_i2c_master_target_set(&config->i2c_dev, addr);
/* Start the transfer */
if (msgs->flags & I2C_MSG_READ) {
status = alt_avalon_i2c_master_receive_using_interrupts(
&config->i2c_dev,
msgs->buf, msgs->len,
restart, stop);
} else {
status = alt_avalon_i2c_master_transmit_using_interrupts
(&config->i2c_dev,
msgs->buf, msgs->len,
restart, stop);
}
/* Return an error if the transfer didn't
* start successfully e.g., if the bus was busy
*/
if (status != ALT_AVALON_I2C_SUCCESS) {
LOG_ERR("i2c transfer error %lu\n", status);
rc = -EIO;
goto i2c_transfer_err;
}
timeout = NIOS2_I2C_TIMEOUT_USEC;
while (timeout) {
k_busy_wait(1);
status = alt_avalon_i2c_interrupt_transaction_status(
&config->i2c_dev);
if (status == ALT_AVALON_I2C_SUCCESS) {
break;
}
timeout--;
}
if (timeout <= 0) {
LOG_ERR("i2c busy or timeout error %lu\n", status);
rc = -EIO;
goto i2c_transfer_err;
}
/* move to the next message */
msgs++;
}
i2c_transfer_err:
alt_avalon_i2c_disable(&config->i2c_dev);
k_sem_give(&config->sem_lock);
return rc;
}
static void i2c_nios2_isr(const struct device *dev)
{
struct i2c_nios2_config *config = DEV_CFG(dev);
/* Call Altera HAL driver ISR */
alt_handle_irq(&config->i2c_dev, DT_INST_IRQN(0));
}
static int i2c_nios2_init(const struct device *dev);
static struct i2c_driver_api i2c_nios2_driver_api = {
.configure = i2c_nios2_configure,
.transfer = i2c_nios2_transfer,
};
static struct i2c_nios2_config i2c_nios2_cfg = {
.i2c_dev = {
.i2c_base = (alt_u32 *)DT_INST_REG_ADDR(0),
.irq_controller_ID = I2C_0_IRQ_INTERRUPT_CONTROLLER_ID,
.irq_ID = DT_INST_IRQN(0),
.ip_freq_in_hz = DT_INST_PROP(0, clock_frequency),
},
};
DEVICE_DT_INST_DEFINE(0, &i2c_nios2_init, NULL,
NULL, &i2c_nios2_cfg,
POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,
&i2c_nios2_driver_api);
static int i2c_nios2_init(const struct device *dev)
{
struct i2c_nios2_config *config = DEV_CFG(dev);
int rc;
/* initialize semaphore */
k_sem_init(&config->sem_lock, 1, 1);
rc = i2c_nios2_configure(dev,
I2C_MODE_MASTER |
I2C_SPEED_SET(I2C_SPEED_STANDARD));
if (rc) {
LOG_ERR("i2c configure failed %d\n", rc);
return rc;
}
/* clear ISR register content */
alt_avalon_i2c_int_clear(&config->i2c_dev,
ALT_AVALON_I2C_ISR_ALL_CLEARABLE_INTS_MSK);
IRQ_CONNECT(DT_INST_IRQN(0), DT_INST_IRQ(0, priority),
i2c_nios2_isr, DEVICE_DT_INST_GET(0), 0);
irq_enable(DT_INST_IRQN(0));
return 0;
}