zephyr/drivers/i2c/i2c_mcux_lpi2c.c

280 lines
6.9 KiB
C

/*
* Copyright (c) 2016 Freescale Semiconductor, Inc.
* Copyright (c) 2019, NXP
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT nxp_imx_lpi2c
#include <errno.h>
#include <drivers/i2c.h>
#include <drivers/clock_control.h>
#include <fsl_lpi2c.h>
#include <logging/log.h>
LOG_MODULE_REGISTER(mcux_lpi2c);
#include "i2c-priv.h"
/* Wait for the duration of 12 bits to detect a NAK after a bus
* address scan. (10 appears sufficient, 20% safety factor.)
*/
#define SCAN_DELAY_US(baudrate) (12 * USEC_PER_SEC / baudrate)
struct mcux_lpi2c_config {
LPI2C_Type *base;
const struct device *clock_dev;
clock_control_subsys_t clock_subsys;
void (*irq_config_func)(const struct device *dev);
uint32_t bitrate;
uint32_t bus_idle_timeout_ns;
};
struct mcux_lpi2c_data {
lpi2c_master_handle_t handle;
struct k_sem lock;
struct k_sem device_sync_sem;
status_t callback_status;
};
static int mcux_lpi2c_configure(const struct device *dev,
uint32_t dev_config_raw)
{
const struct mcux_lpi2c_config *config = dev->config;
struct mcux_lpi2c_data *data = dev->data;
LPI2C_Type *base = config->base;
uint32_t clock_freq;
uint32_t baudrate;
int ret;
if (!(I2C_MODE_MASTER & dev_config_raw)) {
return -EINVAL;
}
if (I2C_ADDR_10_BITS & dev_config_raw) {
return -EINVAL;
}
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;
}
if (clock_control_get_rate(config->clock_dev, config->clock_subsys,
&clock_freq)) {
return -EINVAL;
}
ret = k_sem_take(&data->lock, K_FOREVER);
if (ret) {
return ret;
}
LPI2C_MasterSetBaudRate(base, clock_freq, baudrate);
k_sem_give(&data->lock);
return 0;
}
static void mcux_lpi2c_master_transfer_callback(LPI2C_Type *base,
lpi2c_master_handle_t *handle,
status_t status, void *userData)
{
struct mcux_lpi2c_data *data = userData;
ARG_UNUSED(handle);
ARG_UNUSED(base);
data->callback_status = status;
k_sem_give(&data->device_sync_sem);
}
static uint32_t mcux_lpi2c_convert_flags(int msg_flags)
{
uint32_t flags = 0U;
if (!(msg_flags & I2C_MSG_STOP)) {
flags |= kLPI2C_TransferNoStopFlag;
}
if (msg_flags & I2C_MSG_RESTART) {
flags |= kLPI2C_TransferRepeatedStartFlag;
}
return flags;
}
static int mcux_lpi2c_transfer(const struct device *dev, struct i2c_msg *msgs,
uint8_t num_msgs, uint16_t addr)
{
const struct mcux_lpi2c_config *config = dev->config;
struct mcux_lpi2c_data *data = dev->data;
LPI2C_Type *base = config->base;
lpi2c_master_transfer_t transfer;
status_t status;
int ret = 0;
ret = k_sem_take(&data->lock, K_FOREVER);
if (ret) {
return ret;
}
/* Iterate over all the messages */
for (int i = 0; i < num_msgs; i++) {
if (I2C_MSG_ADDR_10_BITS & msgs->flags) {
ret = -ENOTSUP;
break;
}
/* Initialize the transfer descriptor */
transfer.flags = mcux_lpi2c_convert_flags(msgs->flags);
/* Prevent the controller to send a start condition between
* messages, except if explicitly requested.
*/
if (i != 0 && !(msgs->flags & I2C_MSG_RESTART)) {
transfer.flags |= kLPI2C_TransferNoStartFlag;
}
transfer.slaveAddress = addr;
transfer.direction = (msgs->flags & I2C_MSG_READ)
? kLPI2C_Read : kLPI2C_Write;
transfer.subaddress = 0;
transfer.subaddressSize = 0;
transfer.data = msgs->buf;
transfer.dataSize = msgs->len;
/* Start the transfer */
status = LPI2C_MasterTransferNonBlocking(base,
&data->handle, &transfer);
/* Return an error if the transfer didn't start successfully
* e.g., if the bus was busy
*/
if (status != kStatus_Success) {
LPI2C_MasterTransferAbort(base, &data->handle);
ret = -EIO;
break;
}
/* Wait for the transfer to complete */
k_sem_take(&data->device_sync_sem, K_FOREVER);
/* Return an error if the transfer didn't complete
* successfully. e.g., nak, timeout, lost arbitration
*/
if (data->callback_status != kStatus_Success) {
LPI2C_MasterTransferAbort(base, &data->handle);
ret = -EIO;
break;
}
if (msgs->len == 0) {
k_busy_wait(SCAN_DELAY_US(config->bitrate));
if (0 != (base->MSR & LPI2C_MSR_NDF_MASK)) {
LPI2C_MasterTransferAbort(base, &data->handle);
ret = -EIO;
break;
}
}
/* Move to the next message */
msgs++;
}
k_sem_give(&data->lock);
return ret;
}
static void mcux_lpi2c_isr(const struct device *dev)
{
const struct mcux_lpi2c_config *config = dev->config;
struct mcux_lpi2c_data *data = dev->data;
LPI2C_Type *base = config->base;
LPI2C_MasterTransferHandleIRQ(base, &data->handle);
}
static int mcux_lpi2c_init(const struct device *dev)
{
const struct mcux_lpi2c_config *config = dev->config;
struct mcux_lpi2c_data *data = dev->data;
LPI2C_Type *base = config->base;
uint32_t clock_freq, bitrate_cfg;
lpi2c_master_config_t master_config;
int error;
k_sem_init(&data->lock, 1, 1);
k_sem_init(&data->device_sync_sem, 0, K_SEM_MAX_LIMIT);
if (clock_control_get_rate(config->clock_dev, config->clock_subsys,
&clock_freq)) {
return -EINVAL;
}
LPI2C_MasterGetDefaultConfig(&master_config);
master_config.busIdleTimeout_ns = config->bus_idle_timeout_ns;
LPI2C_MasterInit(base, &master_config, clock_freq);
LPI2C_MasterTransferCreateHandle(base, &data->handle,
mcux_lpi2c_master_transfer_callback,
data);
bitrate_cfg = i2c_map_dt_bitrate(config->bitrate);
error = mcux_lpi2c_configure(dev, I2C_MODE_MASTER | bitrate_cfg);
if (error) {
return error;
}
config->irq_config_func(dev);
return 0;
}
static const struct i2c_driver_api mcux_lpi2c_driver_api = {
.configure = mcux_lpi2c_configure,
.transfer = mcux_lpi2c_transfer,
};
#define I2C_MCUX_LPI2C_INIT(n) \
static void mcux_lpi2c_config_func_##n(const struct device *dev); \
\
static const struct mcux_lpi2c_config mcux_lpi2c_config_##n = { \
.base = (LPI2C_Type *)DT_INST_REG_ADDR(n), \
.clock_dev = DEVICE_DT_GET(DT_INST_CLOCKS_CTLR(n)), \
.clock_subsys = \
(clock_control_subsys_t)DT_INST_CLOCKS_CELL(n, name),\
.irq_config_func = mcux_lpi2c_config_func_##n, \
.bitrate = DT_INST_PROP(n, clock_frequency), \
.bus_idle_timeout_ns = \
UTIL_AND(DT_INST_NODE_HAS_PROP(n, bus_idle_timeout),\
DT_INST_PROP(n, bus_idle_timeout)), \
}; \
\
static struct mcux_lpi2c_data mcux_lpi2c_data_##n; \
\
DEVICE_DT_INST_DEFINE(n, &mcux_lpi2c_init, NULL, \
&mcux_lpi2c_data_##n, \
&mcux_lpi2c_config_##n, POST_KERNEL, \
CONFIG_KERNEL_INIT_PRIORITY_DEVICE, \
&mcux_lpi2c_driver_api); \
\
static void mcux_lpi2c_config_func_##n(const struct device *dev) \
{ \
IRQ_CONNECT(DT_INST_IRQN(n), \
DT_INST_IRQ(n, priority), \
mcux_lpi2c_isr, \
DEVICE_DT_INST_GET(n), 0); \
\
irq_enable(DT_INST_IRQN(n)); \
}
DT_INST_FOREACH_STATUS_OKAY(I2C_MCUX_LPI2C_INIT)