blob: fd6ca2842019d1ded4ef7f7a7f30831733cb5cb9 [file] [log] [blame] [edit]
/*
* Copyright (c) 2018 Diego Sueiro, <diego.sueiro@gmail.com>
* Copyright 2022 NXP
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT fsl_imx21_i2c
#include <errno.h>
#include <zephyr/drivers/i2c.h>
#include <soc.h>
#include <i2c_imx.h>
#include <zephyr/sys/util.h>
#include <zephyr/drivers/pinctrl.h>
#include <zephyr/logging/log.h>
#include <zephyr/irq.h>
LOG_MODULE_REGISTER(i2c_imx);
#include "i2c-priv.h"
#define DEV_BASE(dev) \
((I2C_Type *)((const struct i2c_imx_config * const)(dev)->config)->base)
struct i2c_imx_config {
I2C_Type *base;
void (*irq_config_func)(const struct device *dev);
uint32_t bitrate;
const struct pinctrl_dev_config *pincfg;
};
struct i2c_master_transfer {
const uint8_t *txBuff;
volatile uint8_t *rxBuff;
volatile uint32_t cmdSize;
volatile uint32_t txSize;
volatile uint32_t rxSize;
volatile bool isBusy;
volatile uint32_t currentDir;
volatile uint32_t currentMode;
volatile bool ack;
};
struct i2c_imx_data {
struct i2c_master_transfer transfer;
struct k_sem device_sync_sem;
};
static bool i2c_imx_write(const struct device *dev, uint8_t *txBuffer,
uint32_t txSize)
{
I2C_Type *base = DEV_BASE(dev);
struct i2c_imx_data *data = dev->data;
struct i2c_master_transfer *transfer = &data->transfer;
transfer->isBusy = true;
/* Clear I2C interrupt flag to avoid spurious interrupt */
I2C_ClearStatusFlag(base, i2cStatusInterrupt);
/* Set I2C work under Tx mode */
I2C_SetDirMode(base, i2cDirectionTransmit);
transfer->currentDir = i2cDirectionTransmit;
transfer->txBuff = txBuffer;
transfer->txSize = txSize;
I2C_WriteByte(base, *transfer->txBuff);
transfer->txBuff++;
transfer->txSize--;
/* Enable I2C interrupt, subsequent data transfer will be handled
* in ISR.
*/
I2C_SetIntCmd(base, true);
/* Wait for the transfer to complete */
k_sem_take(&data->device_sync_sem, K_FOREVER);
return transfer->ack;
}
static void i2c_imx_read(const struct device *dev, uint8_t *rxBuffer,
uint32_t rxSize)
{
I2C_Type *base = DEV_BASE(dev);
struct i2c_imx_data *data = dev->data;
struct i2c_master_transfer *transfer = &data->transfer;
transfer->isBusy = true;
/* Clear I2C interrupt flag to avoid spurious interrupt */
I2C_ClearStatusFlag(base, i2cStatusInterrupt);
/* Change to receive state. */
I2C_SetDirMode(base, i2cDirectionReceive);
transfer->currentDir = i2cDirectionReceive;
transfer->rxBuff = rxBuffer;
transfer->rxSize = rxSize;
if (transfer->rxSize == 1U) {
/* Send Nack */
I2C_SetAckBit(base, false);
} else {
/* Send Ack */
I2C_SetAckBit(base, true);
}
/* dummy read to clock in 1st byte */
I2C_ReadByte(base);
/* Enable I2C interrupt, subsequent data transfer will be handled
* in ISR.
*/
I2C_SetIntCmd(base, true);
/* Wait for the transfer to complete */
k_sem_take(&data->device_sync_sem, K_FOREVER);
}
static int i2c_imx_configure(const struct device *dev,
uint32_t dev_config_raw)
{
I2C_Type *base = DEV_BASE(dev);
struct i2c_imx_data *data = dev->data;
struct i2c_master_transfer *transfer = &data->transfer;
uint32_t baudrate;
if (!(I2C_MODE_CONTROLLER & dev_config_raw)) {
return -EINVAL;
}
if (I2C_ADDR_10_BITS & dev_config_raw) {
return -EINVAL;
}
/* Initialize I2C state structure content. */
transfer->txBuff = 0;
transfer->rxBuff = 0;
transfer->cmdSize = 0U;
transfer->txSize = 0U;
transfer->rxSize = 0U;
transfer->isBusy = false;
transfer->currentDir = i2cDirectionReceive;
transfer->currentMode = i2cModeSlave;
switch (I2C_SPEED_GET(dev_config_raw)) {
case I2C_SPEED_STANDARD:
baudrate = KHZ(100);
break;
case I2C_SPEED_FAST:
baudrate = KHZ(400);
break;
case I2C_SPEED_FAST_PLUS:
baudrate = MHZ(1);
break;
default:
return -EINVAL;
}
/* Setup I2C init structure. */
i2c_init_config_t i2cInitConfig = {
.baudRate = baudrate,
.slaveAddress = 0x00
};
i2cInitConfig.clockRate = get_i2c_clock_freq(base);
I2C_Init(base, &i2cInitConfig);
I2C_Enable(base);
return 0;
}
static int i2c_imx_send_addr(const struct device *dev, uint16_t addr,
uint8_t flags)
{
uint8_t byte0 = addr << 1;
byte0 |= (flags & I2C_MSG_RW_MASK) == I2C_MSG_READ;
return i2c_imx_write(dev, &byte0, 1);
}
static int i2c_imx_transfer(const struct device *dev, struct i2c_msg *msgs,
uint8_t num_msgs, uint16_t addr)
{
I2C_Type *base = DEV_BASE(dev);
struct i2c_imx_data *data = dev->data;
struct i2c_master_transfer *transfer = &data->transfer;
uint16_t timeout = UINT16_MAX;
int result = -EIO;
if (!num_msgs) {
return 0;
}
/* Wait until bus not busy */
while ((I2C_I2SR_REG(base) & i2cStatusBusBusy) && (--timeout)) {
}
if (timeout == 0U) {
return result;
}
/* Make sure we're in a good state so slave recognises the Start */
I2C_SetWorkMode(base, i2cModeSlave);
transfer->currentMode = i2cModeSlave;
/* Switch back to Rx direction. */
I2C_SetDirMode(base, i2cDirectionReceive);
transfer->currentDir = i2cDirectionReceive;
/* Start condition */
I2C_SetDirMode(base, i2cDirectionTransmit);
transfer->currentDir = i2cDirectionTransmit;
I2C_SetWorkMode(base, i2cModeMaster);
transfer->currentMode = i2cModeMaster;
/* Send address after any Start condition */
if (!i2c_imx_send_addr(dev, addr, msgs->flags)) {
goto finish; /* No ACK received */
}
do {
if (msgs->flags & I2C_MSG_RESTART) {
I2C_SendRepeatStart(base);
if (!i2c_imx_send_addr(dev, addr, msgs->flags)) {
goto finish; /* No ACK received */
}
}
/* Transfer data */
if (msgs->len) {
if ((msgs->flags & I2C_MSG_RW_MASK) == I2C_MSG_READ) {
i2c_imx_read(dev, msgs->buf, msgs->len);
} else {
if (!i2c_imx_write(dev, msgs->buf, msgs->len)) {
goto finish; /* No ACK received */
}
}
}
if (msgs->flags & I2C_MSG_STOP) {
I2C_SetWorkMode(base, i2cModeSlave);
transfer->currentMode = i2cModeSlave;
I2C_SetDirMode(base, i2cDirectionReceive);
transfer->currentDir = i2cDirectionReceive;
}
/* Next message */
msgs++;
num_msgs--;
} while (num_msgs);
/* Complete without error */
result = 0;
return result;
finish:
I2C_SetWorkMode(base, i2cModeSlave);
transfer->currentMode = i2cModeSlave;
I2C_SetDirMode(base, i2cDirectionReceive);
transfer->currentDir = i2cDirectionReceive;
return result;
}
static void i2c_imx_isr(const struct device *dev)
{
I2C_Type *base = DEV_BASE(dev);
struct i2c_imx_data *data = dev->data;
struct i2c_master_transfer *transfer = &data->transfer;
/* Clear interrupt flag. */
I2C_ClearStatusFlag(base, i2cStatusInterrupt);
/* Exit the ISR if no transfer is happening for this instance. */
if (!transfer->isBusy) {
return;
}
if (i2cModeMaster == transfer->currentMode) {
if (i2cDirectionTransmit == transfer->currentDir) {
/* Normal write operation. */
transfer->ack =
!(I2C_GetStatusFlag(base, i2cStatusReceivedAck));
if (transfer->txSize == 0U) {
/* Close I2C interrupt. */
I2C_SetIntCmd(base, false);
/* Release I2C Bus. */
transfer->isBusy = false;
k_sem_give(&data->device_sync_sem);
} else {
I2C_WriteByte(base, *transfer->txBuff);
transfer->txBuff++;
transfer->txSize--;
}
} else {
/* Normal read operation. */
if (transfer->rxSize == 2U) {
/* Send Nack */
I2C_SetAckBit(base, false);
} else {
/* Send Ack */
I2C_SetAckBit(base, true);
}
if (transfer->rxSize == 1U) {
/* Switch back to Tx direction to avoid
* additional I2C bus read.
*/
I2C_SetDirMode(base, i2cDirectionTransmit);
transfer->currentDir = i2cDirectionTransmit;
}
*transfer->rxBuff = I2C_ReadByte(base);
transfer->rxBuff++;
transfer->rxSize--;
/* receive finished. */
if (transfer->rxSize == 0U) {
/* Close I2C interrupt. */
I2C_SetIntCmd(base, false);
/* Release I2C Bus. */
transfer->isBusy = false;
k_sem_give(&data->device_sync_sem);
}
}
}
}
static int i2c_imx_init(const struct device *dev)
{
const struct i2c_imx_config *config = dev->config;
struct i2c_imx_data *data = dev->data;
uint32_t bitrate_cfg;
int error;
k_sem_init(&data->device_sync_sem, 0, K_SEM_MAX_LIMIT);
error = pinctrl_apply_state(config->pincfg, PINCTRL_STATE_DEFAULT);
if (error) {
return error;
}
bitrate_cfg = i2c_map_dt_bitrate(config->bitrate);
error = i2c_imx_configure(dev, I2C_MODE_CONTROLLER | bitrate_cfg);
if (error) {
return error;
}
config->irq_config_func(dev);
return 0;
}
static const struct i2c_driver_api i2c_imx_driver_api = {
.configure = i2c_imx_configure,
.transfer = i2c_imx_transfer,
};
#define I2C_IMX_INIT(n) \
PINCTRL_DT_INST_DEFINE(n); \
static void i2c_imx_config_func_##n(const struct device *dev); \
\
static const struct i2c_imx_config i2c_imx_config_##n = { \
.base = (I2C_Type *)DT_INST_REG_ADDR(n), \
.irq_config_func = i2c_imx_config_func_##n, \
.bitrate = DT_INST_PROP(n, clock_frequency), \
.pincfg = PINCTRL_DT_INST_DEV_CONFIG_GET(n), \
}; \
\
static struct i2c_imx_data i2c_imx_data_##n; \
\
I2C_DEVICE_DT_INST_DEFINE(n, \
i2c_imx_init, \
NULL, \
&i2c_imx_data_##n, &i2c_imx_config_##n, \
POST_KERNEL, \
CONFIG_I2C_INIT_PRIORITY, \
&i2c_imx_driver_api); \
\
static void i2c_imx_config_func_##n(const struct device *dev) \
{ \
ARG_UNUSED(dev); \
\
IRQ_CONNECT(DT_INST_IRQN(n), \
DT_INST_IRQ(n, priority), \
i2c_imx_isr, DEVICE_DT_INST_GET(n), 0); \
\
irq_enable(DT_INST_IRQN(n)); \
}
DT_INST_FOREACH_STATUS_OKAY(I2C_IMX_INIT)