320 lines
8.6 KiB
C
320 lines
8.6 KiB
C
/*
|
|
* Copyright (c) 2018, Nordic Semiconductor ASA
|
|
*
|
|
* SPDX-License-Identifier: Apache-2.0
|
|
*/
|
|
|
|
|
|
#include <drivers/i2c.h>
|
|
#include <dt-bindings/i2c/i2c.h>
|
|
#include <nrfx_twi.h>
|
|
|
|
#include <logging/log.h>
|
|
LOG_MODULE_REGISTER(i2c_nrfx_twi, CONFIG_I2C_LOG_LEVEL);
|
|
|
|
#define I2C_TRANSFER_TIMEOUT_MSEC K_MSEC(500)
|
|
|
|
struct i2c_nrfx_twi_data {
|
|
struct k_sem transfer_sync;
|
|
struct k_sem completion_sync;
|
|
volatile nrfx_err_t res;
|
|
uint32_t dev_config;
|
|
#ifdef CONFIG_PM_DEVICE
|
|
enum pm_device_state pm_state;
|
|
#endif
|
|
};
|
|
|
|
struct i2c_nrfx_twi_config {
|
|
nrfx_twi_t twi;
|
|
nrfx_twi_config_t config;
|
|
};
|
|
|
|
static inline struct i2c_nrfx_twi_data *get_dev_data(const struct device *dev)
|
|
{
|
|
return dev->data;
|
|
}
|
|
|
|
static inline
|
|
const struct i2c_nrfx_twi_config *get_dev_config(const struct device *dev)
|
|
{
|
|
return dev->config;
|
|
}
|
|
|
|
static int i2c_nrfx_twi_transfer(const struct device *dev,
|
|
struct i2c_msg *msgs,
|
|
uint8_t num_msgs, uint16_t addr)
|
|
{
|
|
int ret = 0;
|
|
|
|
k_sem_take(&(get_dev_data(dev)->transfer_sync), K_FOREVER);
|
|
|
|
/* Dummy take on completion_sync sem to be sure that it is empty */
|
|
k_sem_take(&(get_dev_data(dev)->completion_sync), K_NO_WAIT);
|
|
|
|
nrfx_twi_enable(&get_dev_config(dev)->twi);
|
|
|
|
for (size_t i = 0; i < num_msgs; i++) {
|
|
if (I2C_MSG_ADDR_10_BITS & msgs[i].flags) {
|
|
ret = -ENOTSUP;
|
|
break;
|
|
}
|
|
|
|
nrfx_twi_xfer_desc_t cur_xfer = {
|
|
.p_primary_buf = msgs[i].buf,
|
|
.primary_length = msgs[i].len,
|
|
.address = addr,
|
|
.type = (msgs[i].flags & I2C_MSG_READ) ?
|
|
NRFX_TWI_XFER_RX : NRFX_TWI_XFER_TX
|
|
};
|
|
uint32_t xfer_flags = 0;
|
|
nrfx_err_t res;
|
|
|
|
/* In case the STOP condition is not supposed to appear after
|
|
* the current message, check what is requested further:
|
|
*/
|
|
if (!(msgs[i].flags & I2C_MSG_STOP)) {
|
|
/* - if the transfer consists of more messages
|
|
* and the I2C repeated START is not requested
|
|
* to appear before the next message, suspend
|
|
* the transfer after the current message,
|
|
* so that it can be resumed with the next one,
|
|
* resulting in the two messages merged into
|
|
* a continuous transfer on the bus
|
|
*/
|
|
if ((i < (num_msgs - 1)) &&
|
|
!(msgs[i + 1].flags & I2C_MSG_RESTART)) {
|
|
xfer_flags |= NRFX_TWI_FLAG_SUSPEND;
|
|
/* - otherwise, just finish the transfer without
|
|
* generating the STOP condition, unless the current
|
|
* message is an RX request, for which such feature
|
|
* is not supported
|
|
*/
|
|
} else if (msgs[i].flags & I2C_MSG_READ) {
|
|
ret = -ENOTSUP;
|
|
break;
|
|
} else {
|
|
xfer_flags |= NRFX_TWI_FLAG_TX_NO_STOP;
|
|
}
|
|
}
|
|
|
|
res = nrfx_twi_xfer(&get_dev_config(dev)->twi,
|
|
&cur_xfer,
|
|
xfer_flags);
|
|
if (res != NRFX_SUCCESS) {
|
|
if (res == NRFX_ERROR_BUSY) {
|
|
ret = -EBUSY;
|
|
break;
|
|
} else {
|
|
ret = -EIO;
|
|
break;
|
|
}
|
|
}
|
|
|
|
ret = k_sem_take(&(get_dev_data(dev)->completion_sync),
|
|
I2C_TRANSFER_TIMEOUT_MSEC);
|
|
if (ret != 0) {
|
|
/* Whatever the frequency, completion_sync should have
|
|
* been given by the event handler.
|
|
*
|
|
* If it hasn't, it's probably due to an hardware issue
|
|
* on the I2C line, for example a short between SDA and
|
|
* GND.
|
|
* This is issue has also been when trying to use the
|
|
* I2C bus during MCU internal flash erase.
|
|
*
|
|
* In many situation, a retry is sufficient.
|
|
* However, some time the I2C device get stuck and need
|
|
* help to recover.
|
|
* Therefore we always call nrfx_twi_bus_recover() to
|
|
* make sure everything has been done to restore the
|
|
* bus from this error.
|
|
*/
|
|
LOG_ERR("Error on I2C line occurred for message %d", i);
|
|
nrfx_twi_disable(&get_dev_config(dev)->twi);
|
|
nrfx_twi_bus_recover(get_dev_config(dev)->config.scl,
|
|
get_dev_config(dev)->config.sda);
|
|
ret = -EIO;
|
|
break;
|
|
}
|
|
|
|
res = get_dev_data(dev)->res;
|
|
if (res != NRFX_SUCCESS) {
|
|
LOG_ERR("Error 0x%08X occurred for message %d", res, i);
|
|
ret = -EIO;
|
|
break;
|
|
}
|
|
}
|
|
|
|
nrfx_twi_disable(&get_dev_config(dev)->twi);
|
|
k_sem_give(&(get_dev_data(dev)->transfer_sync));
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void event_handler(nrfx_twi_evt_t const *p_event, void *p_context)
|
|
{
|
|
struct i2c_nrfx_twi_data *dev_data = p_context;
|
|
|
|
switch (p_event->type) {
|
|
case NRFX_TWI_EVT_DONE:
|
|
dev_data->res = NRFX_SUCCESS;
|
|
break;
|
|
case NRFX_TWI_EVT_ADDRESS_NACK:
|
|
dev_data->res = NRFX_ERROR_DRV_TWI_ERR_ANACK;
|
|
break;
|
|
case NRFX_TWI_EVT_DATA_NACK:
|
|
dev_data->res = NRFX_ERROR_DRV_TWI_ERR_DNACK;
|
|
break;
|
|
default:
|
|
dev_data->res = NRFX_ERROR_INTERNAL;
|
|
break;
|
|
}
|
|
|
|
k_sem_give(&dev_data->completion_sync);
|
|
}
|
|
|
|
static int i2c_nrfx_twi_configure(const struct device *dev,
|
|
uint32_t dev_config)
|
|
{
|
|
nrfx_twi_t const *inst = &(get_dev_config(dev)->twi);
|
|
|
|
if (I2C_ADDR_10_BITS & dev_config) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
switch (I2C_SPEED_GET(dev_config)) {
|
|
case I2C_SPEED_STANDARD:
|
|
nrf_twi_frequency_set(inst->p_twi, NRF_TWI_FREQ_100K);
|
|
break;
|
|
case I2C_SPEED_FAST:
|
|
nrf_twi_frequency_set(inst->p_twi, NRF_TWI_FREQ_400K);
|
|
break;
|
|
default:
|
|
LOG_ERR("unsupported speed");
|
|
return -EINVAL;
|
|
}
|
|
get_dev_data(dev)->dev_config = dev_config;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct i2c_driver_api i2c_nrfx_twi_driver_api = {
|
|
.configure = i2c_nrfx_twi_configure,
|
|
.transfer = i2c_nrfx_twi_transfer,
|
|
};
|
|
|
|
static int init_twi(const struct device *dev)
|
|
{
|
|
struct i2c_nrfx_twi_data *dev_data = get_dev_data(dev);
|
|
nrfx_err_t result = nrfx_twi_init(&get_dev_config(dev)->twi,
|
|
&get_dev_config(dev)->config,
|
|
event_handler, dev_data);
|
|
if (result != NRFX_SUCCESS) {
|
|
LOG_ERR("Failed to initialize device: %s",
|
|
dev->name);
|
|
return -EBUSY;
|
|
}
|
|
#ifdef CONFIG_PM_DEVICE
|
|
get_dev_data(dev)->pm_state = PM_DEVICE_STATE_ACTIVE;
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM_DEVICE
|
|
static int twi_nrfx_pm_control(const struct device *dev,
|
|
uint32_t ctrl_command,
|
|
enum pm_device_state *state)
|
|
{
|
|
int ret = 0;
|
|
enum pm_device_state pm_current_state = get_dev_data(dev)->pm_state;
|
|
|
|
if (ctrl_command == PM_DEVICE_STATE_SET) {
|
|
enum pm_device_state new_state = *state;
|
|
|
|
if (new_state != pm_current_state) {
|
|
switch (new_state) {
|
|
case PM_DEVICE_STATE_ACTIVE:
|
|
init_twi(dev);
|
|
if (get_dev_data(dev)->dev_config) {
|
|
i2c_nrfx_twi_configure(
|
|
dev,
|
|
get_dev_data(dev)->dev_config);
|
|
}
|
|
break;
|
|
|
|
case PM_DEVICE_STATE_LOW_POWER:
|
|
case PM_DEVICE_STATE_SUSPEND:
|
|
case PM_DEVICE_STATE_OFF:
|
|
if (pm_current_state == PM_DEVICE_STATE_ACTIVE) {
|
|
nrfx_twi_uninit(&get_dev_config(dev)->twi);
|
|
}
|
|
break;
|
|
|
|
default:
|
|
ret = -ENOTSUP;
|
|
}
|
|
if (!ret) {
|
|
get_dev_data(dev)->pm_state = new_state;
|
|
}
|
|
}
|
|
} else {
|
|
__ASSERT_NO_MSG(ctrl_command == PM_DEVICE_STATE_GET);
|
|
*state = get_dev_data(dev)->pm_state;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
#endif /* CONFIG_PM_DEVICE */
|
|
|
|
#define I2C_NRFX_TWI_INVALID_FREQUENCY ((nrf_twi_frequency_t)-1)
|
|
#define I2C_NRFX_TWI_FREQUENCY(bitrate) \
|
|
(bitrate == I2C_BITRATE_STANDARD ? NRF_TWI_FREQ_100K \
|
|
: bitrate == 250000 ? NRF_TWI_FREQ_250K \
|
|
: bitrate == I2C_BITRATE_FAST ? NRF_TWI_FREQ_400K \
|
|
: I2C_NRFX_TWI_INVALID_FREQUENCY)
|
|
#define I2C(idx) DT_NODELABEL(i2c##idx)
|
|
#define I2C_FREQUENCY(idx) \
|
|
I2C_NRFX_TWI_FREQUENCY(DT_PROP(I2C(idx), clock_frequency))
|
|
|
|
#define I2C_NRFX_TWI_DEVICE(idx) \
|
|
BUILD_ASSERT(I2C_FREQUENCY(idx) != \
|
|
I2C_NRFX_TWI_INVALID_FREQUENCY, \
|
|
"Wrong I2C " #idx " frequency setting in dts"); \
|
|
static int twi_##idx##_init(const struct device *dev) \
|
|
{ \
|
|
IRQ_CONNECT(DT_IRQN(I2C(idx)), DT_IRQ(I2C(idx), priority), \
|
|
nrfx_isr, nrfx_twi_##idx##_irq_handler, 0); \
|
|
return init_twi(dev); \
|
|
} \
|
|
static struct i2c_nrfx_twi_data twi_##idx##_data = { \
|
|
.transfer_sync = Z_SEM_INITIALIZER( \
|
|
twi_##idx##_data.transfer_sync, 1, 1), \
|
|
.completion_sync = Z_SEM_INITIALIZER( \
|
|
twi_##idx##_data.completion_sync, 0, 1) \
|
|
}; \
|
|
static const struct i2c_nrfx_twi_config twi_##idx##z_config = { \
|
|
.twi = NRFX_TWI_INSTANCE(idx), \
|
|
.config = { \
|
|
.scl = DT_PROP(I2C(idx), scl_pin), \
|
|
.sda = DT_PROP(I2C(idx), sda_pin), \
|
|
.frequency = I2C_FREQUENCY(idx), \
|
|
} \
|
|
}; \
|
|
DEVICE_DT_DEFINE(I2C(idx), \
|
|
twi_##idx##_init, \
|
|
twi_nrfx_pm_control, \
|
|
&twi_##idx##_data, \
|
|
&twi_##idx##z_config, \
|
|
POST_KERNEL, \
|
|
CONFIG_I2C_INIT_PRIORITY, \
|
|
&i2c_nrfx_twi_driver_api)
|
|
|
|
#ifdef CONFIG_I2C_0_NRF_TWI
|
|
I2C_NRFX_TWI_DEVICE(0);
|
|
#endif
|
|
|
|
#ifdef CONFIG_I2C_1_NRF_TWI
|
|
I2C_NRFX_TWI_DEVICE(1);
|
|
#endif
|