zephyr/drivers/i2c/i2c_nrfx_twim.c

392 lines
11 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 <pm/device.h>
#include <nrfx_twim.h>
#include <sys/util.h>
#include <logging/log.h>
LOG_MODULE_REGISTER(i2c_nrfx_twim, CONFIG_I2C_LOG_LEVEL);
#define I2C_TRANSFER_TIMEOUT_MSEC K_MSEC(500)
struct i2c_nrfx_twim_data {
struct k_sem transfer_sync;
struct k_sem completion_sync;
volatile nrfx_err_t res;
uint32_t dev_config;
uint8_t *msg_buf;
};
struct i2c_nrfx_twim_config {
nrfx_twim_t twim;
nrfx_twim_config_t config;
uint16_t concat_buf_size;
uint16_t flash_buf_max_size;
};
static int i2c_nrfx_twim_transfer(const struct device *dev,
struct i2c_msg *msgs,
uint8_t num_msgs, uint16_t addr)
{
struct i2c_nrfx_twim_data *dev_data = dev->data;
const struct i2c_nrfx_twim_config *dev_config = dev->config;
int ret = 0;
uint8_t *msg_buf = dev_data->msg_buf;
uint16_t msg_buf_used = 0;
uint16_t concat_buf_size = dev_config->concat_buf_size;
nrfx_twim_xfer_desc_t cur_xfer = {
.address = addr
};
k_sem_take(&dev_data->transfer_sync, K_FOREVER);
/* Dummy take on completion_sync sem to be sure that it is empty */
k_sem_take(&dev_data->completion_sync, K_NO_WAIT);
nrfx_twim_enable(&dev_config->twim);
for (size_t i = 0; i < num_msgs; i++) {
if (I2C_MSG_ADDR_10_BITS & msgs[i].flags) {
ret = -ENOTSUP;
break;
}
/* This fragment needs to be merged with the next one if:
* - it is not the last fragment
* - it does not end a bus transaction
* - the next fragment does not start a bus transaction
* - the direction of the next fragment is the same as this one
*/
bool concat_next = ((i + 1) < num_msgs)
&& !(msgs[i].flags & I2C_MSG_STOP)
&& !(msgs[i + 1].flags & I2C_MSG_RESTART)
&& ((msgs[i].flags & I2C_MSG_READ)
== (msgs[i + 1].flags & I2C_MSG_READ));
/* If we need to concatenate the next message, or we've
* already committed to concatenate this message, add it to
* the buffer after verifying there's room.
*/
if (concat_next || (msg_buf_used != 0)) {
if ((msg_buf_used + msgs[i].len) > concat_buf_size) {
LOG_ERR("Need to use concatenation buffer and "
"provided size is insufficient "
"(%u + %u > %u). "
"Adjust the zephyr,concat-buf-size "
"property in the \"%s\" node.",
msg_buf_used, msgs[i].len,
concat_buf_size, dev->name);
ret = -ENOSPC;
break;
}
if (!(msgs[i].flags & I2C_MSG_READ)) {
memcpy(msg_buf + msg_buf_used,
msgs[i].buf,
msgs[i].len);
}
msg_buf_used += msgs[i].len;
/* TWIM peripherals cannot transfer data directly from
* flash. If a buffer located in flash is provided for
* a write transaction, its content must be copied to
* RAM before the transfer can be requested.
*/
} else if (!(msgs[i].flags & I2C_MSG_READ) &&
!nrfx_is_in_ram(msgs[i].buf)) {
if (msgs[i].len > dev_config->flash_buf_max_size) {
LOG_ERR("Cannot copy flash buffer of size: %u. "
"Adjust the zephyr,flash-buf-max-size "
"property in the \"%s\" node.",
msgs[i].len, dev->name);
ret = -EINVAL;
break;
}
memcpy(msg_buf, msgs[i].buf, msgs[i].len);
msg_buf_used = msgs[i].len;
}
if (concat_next) {
continue;
}
if (msg_buf_used == 0) {
cur_xfer.p_primary_buf = msgs[i].buf;
cur_xfer.primary_length = msgs[i].len;
} else {
cur_xfer.p_primary_buf = msg_buf;
cur_xfer.primary_length = msg_buf_used;
}
cur_xfer.type = (msgs[i].flags & I2C_MSG_READ) ?
NRFX_TWIM_XFER_RX : NRFX_TWIM_XFER_TX;
nrfx_err_t res = nrfx_twim_xfer(&dev_config->twim,
&cur_xfer,
(msgs[i].flags & I2C_MSG_STOP) ?
0 : NRFX_TWIM_FLAG_TX_NO_STOP);
if (res != NRFX_SUCCESS) {
if (res == NRFX_ERROR_BUSY) {
ret = -EBUSY;
break;
} else {
ret = -EIO;
break;
}
}
ret = k_sem_take(&dev_data->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_twim_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_twim_disable(&dev_config->twim);
nrfx_twim_bus_recover(dev_config->config.scl,
dev_config->config.sda);
ret = -EIO;
break;
}
res = dev_data->res;
if (res != NRFX_SUCCESS) {
LOG_ERR("Error 0x%08X occurred for message %d", res, i);
ret = -EIO;
break;
}
/* If concatenated messages were I2C_MSG_READ type, then
* content of concatenation buffer has to be copied back into
* buffers provided by user. */
if ((msgs[i].flags & I2C_MSG_READ)
&& cur_xfer.p_primary_buf == msg_buf) {
int j = i;
while (msg_buf_used >= msgs[j].len) {
msg_buf_used -= msgs[j].len;
memcpy(msgs[j].buf,
msg_buf + msg_buf_used,
msgs[j].len);
j--;
}
}
msg_buf_used = 0;
}
nrfx_twim_disable(&dev_config->twim);
k_sem_give(&dev_data->transfer_sync);
return ret;
}
static void event_handler(nrfx_twim_evt_t const *p_event, void *p_context)
{
struct i2c_nrfx_twim_data *dev_data = p_context;
switch (p_event->type) {
case NRFX_TWIM_EVT_DONE:
dev_data->res = NRFX_SUCCESS;
break;
case NRFX_TWIM_EVT_ADDRESS_NACK:
dev_data->res = NRFX_ERROR_DRV_TWI_ERR_ANACK;
break;
case NRFX_TWIM_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_twim_configure(const struct device *dev,
uint32_t dev_config)
{
const struct i2c_nrfx_twim_config *config = dev->config;
struct i2c_nrfx_twim_data *data = dev->data;
nrfx_twim_t const *inst = &config->twim;
if (I2C_ADDR_10_BITS & dev_config) {
return -EINVAL;
}
switch (I2C_SPEED_GET(dev_config)) {
case I2C_SPEED_STANDARD:
nrf_twim_frequency_set(inst->p_twim, NRF_TWIM_FREQ_100K);
break;
case I2C_SPEED_FAST:
nrf_twim_frequency_set(inst->p_twim, NRF_TWIM_FREQ_400K);
break;
default:
LOG_ERR("unsupported speed");
return -EINVAL;
}
data->dev_config = dev_config;
return 0;
}
static int i2c_nrfx_twim_recover_bus(const struct device *dev)
{
const struct i2c_nrfx_twim_config *config = dev->config;
nrfx_err_t err = nrfx_twim_bus_recover(config->config.scl,
config->config.sda);
return (err == NRFX_SUCCESS ? 0 : -EBUSY);
}
static const struct i2c_driver_api i2c_nrfx_twim_driver_api = {
.configure = i2c_nrfx_twim_configure,
.transfer = i2c_nrfx_twim_transfer,
.recover_bus = i2c_nrfx_twim_recover_bus,
};
static int init_twim(const struct device *dev)
{
const struct i2c_nrfx_twim_config *config = dev->config;
struct i2c_nrfx_twim_data *dev_data = dev->data;
nrfx_err_t result = nrfx_twim_init(&config->twim, &config->config,
event_handler, dev_data);
if (result != NRFX_SUCCESS) {
LOG_ERR("Failed to initialize device: %s",
dev->name);
return -EBUSY;
}
return 0;
}
#ifdef CONFIG_PM_DEVICE
static int twim_nrfx_pm_action(const struct device *dev,
enum pm_device_action action)
{
const struct i2c_nrfx_twim_config *config = dev->config;
struct i2c_nrfx_twim_data *data = dev->data;
int ret = 0;
switch (action) {
case PM_DEVICE_ACTION_RESUME:
init_twim(dev);
if (data->dev_config) {
i2c_nrfx_twim_configure(dev, data->dev_config);
}
break;
case PM_DEVICE_ACTION_SUSPEND:
nrfx_twim_uninit(&config->twim);
break;
default:
ret = -ENOTSUP;
}
return ret;
}
#endif /* CONFIG_PM_DEVICE */
#define I2C_NRFX_TWIM_INVALID_FREQUENCY ((nrf_twim_frequency_t)-1)
#define I2C_NRFX_TWIM_FREQUENCY(bitrate) \
(bitrate == I2C_BITRATE_STANDARD ? NRF_TWIM_FREQ_100K \
: bitrate == 250000 ? NRF_TWIM_FREQ_250K \
: bitrate == I2C_BITRATE_FAST ? NRF_TWIM_FREQ_400K \
: I2C_NRFX_TWIM_INVALID_FREQUENCY)
#define I2C(idx) DT_NODELABEL(i2c##idx)
#define I2C_FREQUENCY(idx) \
I2C_NRFX_TWIM_FREQUENCY(DT_PROP(I2C(idx), clock_frequency))
#define CONCAT_BUF_SIZE(idx) \
COND_CODE_1(DT_NODE_HAS_PROP(I2C(idx), zephyr_concat_buf_size), \
(DT_PROP(I2C(idx), zephyr_concat_buf_size)), (0))
#define FLASH_BUF_MAX_SIZE(idx) \
COND_CODE_1(DT_NODE_HAS_PROP(I2C(idx), zephyr_flash_buf_max_size), \
(DT_PROP(I2C(idx), zephyr_flash_buf_max_size)), (0))
#define USES_MSG_BUF(idx) \
COND_CODE_0(CONCAT_BUF_SIZE(idx), \
(COND_CODE_0(FLASH_BUF_MAX_SIZE(idx), (0), (1))), \
(1))
#define MSG_BUF_SIZE(idx) MAX(CONCAT_BUF_SIZE(idx), FLASH_BUF_MAX_SIZE(idx))
#define I2C_NRFX_TWIM_DEVICE(idx) \
BUILD_ASSERT(I2C_FREQUENCY(idx) != \
I2C_NRFX_TWIM_INVALID_FREQUENCY, \
"Wrong I2C " #idx " frequency setting in dts"); \
static int twim_##idx##_init(const struct device *dev) \
{ \
IRQ_CONNECT(DT_IRQN(I2C(idx)), DT_IRQ(I2C(idx), priority), \
nrfx_isr, nrfx_twim_##idx##_irq_handler, 0); \
return init_twim(dev); \
} \
IF_ENABLED(USES_MSG_BUF(idx), \
(static uint8_t twim_##idx##_msg_buf[MSG_BUF_SIZE(idx)];)) \
static struct i2c_nrfx_twim_data twim_##idx##_data = { \
.transfer_sync = Z_SEM_INITIALIZER( \
twim_##idx##_data.transfer_sync, 1, 1), \
.completion_sync = Z_SEM_INITIALIZER( \
twim_##idx##_data.completion_sync, 0, 1), \
IF_ENABLED(USES_MSG_BUF(idx), \
(.msg_buf = twim_##idx##_msg_buf,)) \
}; \
static const struct i2c_nrfx_twim_config twim_##idx##z_config = { \
.twim = NRFX_TWIM_INSTANCE(idx), \
.config = { \
.scl = DT_PROP(I2C(idx), scl_pin), \
.sda = DT_PROP(I2C(idx), sda_pin), \
.frequency = I2C_FREQUENCY(idx), \
}, \
.concat_buf_size = CONCAT_BUF_SIZE(idx), \
.flash_buf_max_size = FLASH_BUF_MAX_SIZE(idx), \
}; \
PM_DEVICE_DT_DEFINE(I2C(idx), twim_nrfx_pm_action); \
I2C_DEVICE_DT_DEFINE(I2C(idx), \
twim_##idx##_init, \
PM_DEVICE_DT_GET(I2C(idx)), \
&twim_##idx##_data, \
&twim_##idx##z_config, \
POST_KERNEL, \
CONFIG_I2C_INIT_PRIORITY, \
&i2c_nrfx_twim_driver_api)
#ifdef CONFIG_I2C_0_NRF_TWIM
I2C_NRFX_TWIM_DEVICE(0);
#endif
#ifdef CONFIG_I2C_1_NRF_TWIM
I2C_NRFX_TWIM_DEVICE(1);
#endif
#ifdef CONFIG_I2C_2_NRF_TWIM
I2C_NRFX_TWIM_DEVICE(2);
#endif
#ifdef CONFIG_I2C_3_NRF_TWIM
I2C_NRFX_TWIM_DEVICE(3);
#endif