/*
* Copyright (c) 2017, I-SENSE group of ICCS
* Copyright (c) 2017 Linaro Ltd
*
* SPDX-License-Identifier: Apache-2.0
*
* I2C Driver for: STM32F1, STM32F2, STM32F4 and STM32L1
*
*/
#include <drivers/clock_control/stm32_clock_control.h>
#include <drivers/clock_control.h>
#include <sys/util.h>
#include <kernel.h>
#include <soc.h>
#include <stm32_ll_i2c.h>
#include <errno.h>
#include <drivers/i2c.h>
#include "i2c_ll_stm32.h"
#define LOG_LEVEL CONFIG_I2C_LOG_LEVEL
#include <logging/log.h>
LOG_MODULE_REGISTER(i2c_ll_stm32_v1);
#include "i2c-priv.h"
#define STM32_I2C_TRANSFER_TIMEOUT_MSEC 500
#define STM32_I2C_TIMEOUT_USEC 1000
#define I2C_REQUEST_WRITE 0x00
#define I2C_REQUEST_READ 0x01
#define HEADER 0xF0
static void stm32_i2c_generate_start_condition(I2C_TypeDef *i2c)
{
uint16_t cr1 = LL_I2C_ReadReg(i2c, CR1);
if (cr1 & I2C_CR1_STOP) {
LOG_DBG("%s: START while STOP active!", __func__);
LL_I2C_WriteReg(i2c, CR1, cr1 & ~I2C_CR1_STOP);
}
LL_I2C_GenerateStartCondition(i2c);
}
#ifdef CONFIG_I2C_STM32_INTERRUPT
static void stm32_i2c_disable_transfer_interrupts(const struct device *dev)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
I2C_TypeDef *i2c = cfg->i2c;
LL_I2C_DisableIT_TX(i2c);
LL_I2C_DisableIT_RX(i2c);
LL_I2C_DisableIT_EVT(i2c);
LL_I2C_DisableIT_BUF(i2c);
LL_I2C_DisableIT_ERR(i2c);
}
static void stm32_i2c_enable_transfer_interrupts(const struct device *dev)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
I2C_TypeDef *i2c = cfg->i2c;
LL_I2C_EnableIT_ERR(i2c);
LL_I2C_EnableIT_EVT(i2c);
LL_I2C_EnableIT_BUF(i2c);
}
#endif /* CONFIG_I2C_STM32_INTERRUPT */
static void stm32_i2c_reset(const struct device *dev)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
I2C_TypeDef *i2c = cfg->i2c;
uint16_t cr1, cr2, oar1, oar2, trise, ccr;
#if defined(I2C_FLTR_ANOFF) && defined(I2C_FLTR_DNF)
uint16_t fltr;
#endif
/* disable i2c and disable IRQ's */
LL_I2C_Disable(i2c);
#ifdef CONFIG_I2C_STM32_INTERRUPT
stm32_i2c_disable_transfer_interrupts(dev);
#endif
/* save all important registers before reset */
cr1 = LL_I2C_ReadReg(i2c, CR1);
cr2 = LL_I2C_ReadReg(i2c, CR2);
oar1 = LL_I2C_ReadReg(i2c, OAR1);
oar2 = LL_I2C_ReadReg(i2c, OAR2);
ccr = LL_I2C_ReadReg(i2c, CCR);
trise = LL_I2C_ReadReg(i2c, TRISE);
#if defined(I2C_FLTR_ANOFF) && defined(I2C_FLTR_DNF)
fltr = LL_I2C_ReadReg(i2c, FLTR);
#endif
/* reset i2c hardware */
LL_I2C_EnableReset(i2c);
LL_I2C_DisableReset(i2c);
/* restore all important registers after reset */
LL_I2C_WriteReg(i2c, CR1, cr1);
LL_I2C_WriteReg(i2c, CR2, cr2);
/* bit 14 of OAR1 must always be 1 */
oar1 |= (1 << 14);
LL_I2C_WriteReg(i2c, OAR1, oar1);
LL_I2C_WriteReg(i2c, OAR2, oar2);
LL_I2C_WriteReg(i2c, CCR, ccr);
LL_I2C_WriteReg(i2c, TRISE, trise);
#if defined(I2C_FLTR_ANOFF) && defined(I2C_FLTR_DNF)
LL_I2C_WriteReg(i2c, FLTR, fltr);
#endif
}
static void stm32_i2c_master_finish(const struct device *dev)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
I2C_TypeDef *i2c = cfg->i2c;
#ifdef CONFIG_I2C_STM32_INTERRUPT
stm32_i2c_disable_transfer_interrupts(dev);
#endif
#if defined(CONFIG_I2C_SLAVE)
struct i2c_stm32_data *data = DEV_DATA(dev);
data->master_active = false;
if (!data->slave_attached) {
LL_I2C_Disable(i2c);
} else {
stm32_i2c_enable_transfer_interrupts(dev);
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_ACK);
}
#else
LL_I2C_Disable(i2c);
#endif
}
static inline void msg_init(const struct device *dev, struct i2c_msg *msg,
uint8_t *next_msg_flags, uint16_t slave,
uint32_t transfer)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
ARG_UNUSED(next_msg_flags);
#ifdef CONFIG_I2C_STM32_INTERRUPT
k_sem_reset(&data->device_sync_sem);
#endif
data->current.len = msg->len;
data->current.buf = msg->buf;
data->current.flags = msg->flags;
data->current.is_restart = 0U;
data->current.is_write = (transfer == I2C_REQUEST_WRITE);
data->current.is_arlo = 0U;
data->current.is_err = 0U;
data->current.is_nack = 0U;
data->current.msg = msg;
#if defined(CONFIG_I2C_SLAVE)
data->master_active = true;
#endif
data->slave_address = slave;
LL_I2C_Enable(i2c);
LL_I2C_DisableBitPOS(i2c);
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_ACK);
if (msg->flags & I2C_MSG_RESTART) {
stm32_i2c_generate_start_condition(i2c);
}
}
static int32_t msg_end(const struct device *dev, uint8_t *next_msg_flags,
const char *funcname)
{
struct i2c_stm32_data *data = DEV_DATA(dev);
if (data->current.is_nack || data->current.is_err ||
data->current.is_arlo) {
goto error;
}
if (!next_msg_flags) {
stm32_i2c_master_finish(dev);
}
return 0;
error:
if (data->current.is_arlo) {
LOG_DBG("%s: ARLO %d", funcname,
data->current.is_arlo);
data->current.is_arlo = 0U;
}
if (data->current.is_nack) {
LOG_DBG("%s: NACK", funcname);
data->current.is_nack = 0U;
}
if (data->current.is_err) {
LOG_DBG("%s: ERR %d", funcname,
data->current.is_err);
data->current.is_err = 0U;
}
stm32_i2c_master_finish(dev);
return -EIO;
}
#ifdef CONFIG_I2C_STM32_INTERRUPT
static void stm32_i2c_master_mode_end(const struct device *dev)
{
struct i2c_stm32_data *data = DEV_DATA(dev);
k_sem_give(&data->device_sync_sem);
}
static inline void handle_sb(const struct device *dev)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
uint16_t saddr = data->slave_address;
uint8_t slave;
if (I2C_ADDR_10_BITS & data->dev_config) {
slave = (((saddr & 0x0300) >> 7) & 0xFF);
uint8_t header = slave | HEADER;
if (data->current.is_restart == 0U) {
data->current.is_restart = 1U;
} else {
header |= I2C_REQUEST_READ;
data->current.is_restart = 0U;
}
LL_I2C_TransmitData8(i2c, header);
return;
}
slave = (saddr << 1) & 0xFF;
if (data->current.is_write) {
LL_I2C_TransmitData8(i2c, slave | I2C_REQUEST_WRITE);
} else {
LL_I2C_TransmitData8(i2c, slave | I2C_REQUEST_READ);
if (data->current.len == 2) {
LL_I2C_EnableBitPOS(i2c);
}
}
}
static inline void handle_addr(const struct device *dev)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
if (I2C_ADDR_10_BITS & data->dev_config) {
if (!data->current.is_write && data->current.is_restart) {
data->current.is_restart = 0U;
LL_I2C_ClearFlag_ADDR(i2c);
stm32_i2c_generate_start_condition(i2c);
return;
}
}
if (data->current.is_write) {
LL_I2C_ClearFlag_ADDR(i2c);
return;
}
/* according to STM32F1 errata we need to handle these corner cases in
* specific way.
* Please ref to STM32F10xxC/D/E I2C peripheral Errata sheet 2.14.1
*/
if (data->current.len == 0U && IS_ENABLED(CONFIG_SOC_SERIES_STM32F1X)) {
LL_I2C_GenerateStopCondition(i2c);
} else if (data->current.len == 1U) {
/* Single byte reception: enable NACK and clear POS */
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
#ifdef CONFIG_SOC_SERIES_STM32F1X
LL_I2C_ClearFlag_ADDR(i2c);
LL_I2C_GenerateStopCondition(i2c);
#endif
} else if (data->current.len == 2U) {
#ifdef CONFIG_SOC_SERIES_STM32F1X
LL_I2C_ClearFlag_ADDR(i2c);
#endif
/* 2-byte reception: enable NACK and set POS */
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
LL_I2C_EnableBitPOS(i2c);
}
LL_I2C_ClearFlag_ADDR(i2c);
}
static inline void handle_txe(const struct device *dev)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
if (data->current.len) {
data->current.len--;
if (data->current.len == 0U) {
/*
* This is the last byte to transmit disable Buffer
* interrupt and wait for a BTF interrupt
*/
LL_I2C_DisableIT_BUF(i2c);
}
LL_I2C_TransmitData8(i2c, *data->current.buf);
data->current.buf++;
} else {
if (data->current.flags & I2C_MSG_STOP) {
LL_I2C_GenerateStopCondition(i2c);
}
if (LL_I2C_IsActiveFlag_BTF(i2c)) {
/* Read DR to clear BTF flag */
LL_I2C_ReceiveData8(i2c);
}
k_sem_give(&data->device_sync_sem);
}
}
static inline void handle_rxne(const struct device *dev)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
if (data->current.len > 0) {
switch (data->current.len) {
case 1:
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
LL_I2C_DisableBitPOS(i2c);
/* Single byte reception */
if (data->current.flags & I2C_MSG_STOP) {
LL_I2C_GenerateStopCondition(i2c);
}
LL_I2C_DisableIT_BUF(i2c);
data->current.len--;
*data->current.buf = LL_I2C_ReceiveData8(i2c);
data->current.buf++;
k_sem_give(&data->device_sync_sem);
break;
case 2:
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
LL_I2C_EnableBitPOS(i2c);
__fallthrough;
case 3:
/*
* 2-byte, 3-byte reception and for N-2, N-1,
* N when N > 3
*/
LL_I2C_DisableIT_BUF(i2c);
break;
default:
/* N byte reception when N > 3 */
data->current.len--;
*data->current.buf = LL_I2C_ReceiveData8(i2c);
data->current.buf++;
}
} else {
if (data->current.flags & I2C_MSG_STOP) {
LL_I2C_GenerateStopCondition(i2c);
}
k_sem_give(&data->device_sync_sem);
}
}
static inline void handle_btf(const struct device *dev)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
if (data->current.is_write) {
handle_txe(dev);
} else {
uint32_t counter = 0U;
switch (data->current.len) {
case 2:
/*
* Stop condition must be generated before reading the
* last two bytes.
*/
if (data->current.flags & I2C_MSG_STOP) {
LL_I2C_GenerateStopCondition(i2c);
}
for (counter = 2U; counter > 0; counter--) {
data->current.len--;
*data->current.buf = LL_I2C_ReceiveData8(i2c);
data->current.buf++;
}
k_sem_give(&data->device_sync_sem);
break;
case 3:
/* Set NACK before reading N-2 byte*/
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
data->current.len--;
*data->current.buf = LL_I2C_ReceiveData8(i2c);
data->current.buf++;
break;
default:
handle_rxne(dev);
}
}
}
#if defined(CONFIG_I2C_SLAVE)
static void stm32_i2c_slave_event(const struct device *dev)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
const struct i2c_slave_callbacks *slave_cb =
data->slave_cfg->callbacks;
if (LL_I2C_IsActiveFlag_TXE(i2c) && LL_I2C_IsActiveFlag_BTF(i2c)) {
uint8_t val;
slave_cb->read_processed(data->slave_cfg, &val);
LL_I2C_TransmitData8(i2c, val);
return;
}
if (LL_I2C_IsActiveFlag_RXNE(i2c)) {
uint8_t val = LL_I2C_ReceiveData8(i2c);
if (slave_cb->write_received(data->slave_cfg, val)) {
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
}
return;
}
if (LL_I2C_IsActiveFlag_AF(i2c)) {
LL_I2C_ClearFlag_AF(i2c);
}
if (LL_I2C_IsActiveFlag_STOP(i2c)) {
LL_I2C_ClearFlag_STOP(i2c);
slave_cb->stop(data->slave_cfg);
/* Prepare to ACK next transmissions address byte */
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_ACK);
}
if (LL_I2C_IsActiveFlag_ADDR(i2c)) {
uint32_t dir = LL_I2C_GetTransferDirection(i2c);
if (dir == LL_I2C_DIRECTION_READ) {
slave_cb->write_requested(data->slave_cfg);
LL_I2C_EnableIT_RX(i2c);
} else {
uint8_t val;
slave_cb->read_requested(data->slave_cfg, &val);
LL_I2C_TransmitData8(i2c, val);
LL_I2C_EnableIT_TX(i2c);
}
stm32_i2c_enable_transfer_interrupts(dev);
}
}
/* Attach and start I2C as slave */
int i2c_stm32_slave_register(const struct device *dev,
struct i2c_slave_config *config)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
uint32_t bitrate_cfg;
int ret;
if (!config) {
return -EINVAL;
}
if (data->slave_attached) {
return -EBUSY;
}
if (data->master_active) {
return -EBUSY;
}
bitrate_cfg = i2c_map_dt_bitrate(cfg->bitrate);
ret = i2c_stm32_runtime_configure(dev, bitrate_cfg);
if (ret < 0) {
LOG_ERR("i2c: failure initializing");
return ret;
}
data->slave_cfg = config;
LL_I2C_Enable(i2c);
LL_I2C_SetOwnAddress1(i2c, config->address << 1,
LL_I2C_OWNADDRESS1_7BIT);
data->slave_attached = true;
LOG_DBG("i2c: slave registered");
stm32_i2c_enable_transfer_interrupts(dev);
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_ACK);
return 0;
}
int i2c_stm32_slave_unregister(const struct device *dev,
struct i2c_slave_config *config)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
if (!data->slave_attached) {
return -EINVAL;
}
if (data->master_active) {
return -EBUSY;
}
stm32_i2c_disable_transfer_interrupts(dev);
LL_I2C_ClearFlag_AF(i2c);
LL_I2C_ClearFlag_STOP(i2c);
LL_I2C_ClearFlag_ADDR(i2c);
LL_I2C_Disable(i2c);
data->slave_attached = false;
LOG_DBG("i2c: slave unregistered");
return 0;
}
#endif /* defined(CONFIG_I2C_SLAVE) */
void stm32_i2c_event_isr(void *arg)
{
const struct device *dev = (const struct device *)arg;
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
#if defined(CONFIG_I2C_SLAVE)
if (data->slave_attached && !data->master_active) {
stm32_i2c_slave_event(dev);
return;
}
#endif
if (LL_I2C_IsActiveFlag_SB(i2c)) {
handle_sb(dev);
} else if (LL_I2C_IsActiveFlag_ADD10(i2c)) {
LL_I2C_TransmitData8(i2c, data->slave_address);
} else if (LL_I2C_IsActiveFlag_ADDR(i2c)) {
handle_addr(dev);
} else if (LL_I2C_IsActiveFlag_BTF(i2c)) {
handle_btf(dev);
} else if (LL_I2C_IsActiveFlag_TXE(i2c) && data->current.is_write) {
handle_txe(dev);
} else if (LL_I2C_IsActiveFlag_RXNE(i2c) && !data->current.is_write) {
handle_rxne(dev);
}
}
void stm32_i2c_error_isr(void *arg)
{
const struct device *dev = (const struct device *)arg;
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
#if defined(CONFIG_I2C_SLAVE)
if (data->slave_attached && !data->master_active) {
/* No need for a slave error function right now. */
return;
}
#endif
if (LL_I2C_IsActiveFlag_AF(i2c)) {
LL_I2C_ClearFlag_AF(i2c);
LL_I2C_GenerateStopCondition(i2c);
data->current.is_nack = 1U;
goto end;
}
if (LL_I2C_IsActiveFlag_ARLO(i2c)) {
LL_I2C_ClearFlag_ARLO(i2c);
data->current.is_arlo = 1U;
goto end;
}
if (LL_I2C_IsActiveFlag_BERR(i2c)) {
LL_I2C_ClearFlag_BERR(i2c);
data->current.is_err = 1U;
goto end;
}
return;
end:
stm32_i2c_master_mode_end(dev);
}
int32_t stm32_i2c_msg_write(const struct device *dev, struct i2c_msg *msg,
uint8_t *next_msg_flags, uint16_t saddr)
{
struct i2c_stm32_data *data = DEV_DATA(dev);
msg_init(dev, msg, next_msg_flags, saddr, I2C_REQUEST_WRITE);
stm32_i2c_enable_transfer_interrupts(dev);
if (k_sem_take(&data->device_sync_sem,
K_MSEC(STM32_I2C_TRANSFER_TIMEOUT_MSEC)) != 0) {
LOG_DBG("%s: WRITE timeout", __func__);
stm32_i2c_reset(dev);
return -EIO;
}
return msg_end(dev, next_msg_flags, __func__);
}
int32_t stm32_i2c_msg_read(const struct device *dev, struct i2c_msg *msg,
uint8_t *next_msg_flags, uint16_t saddr)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
msg_init(dev, msg, next_msg_flags, saddr, I2C_REQUEST_READ);
stm32_i2c_enable_transfer_interrupts(dev);
LL_I2C_EnableIT_RX(i2c);
if (k_sem_take(&data->device_sync_sem,
K_MSEC(STM32_I2C_TRANSFER_TIMEOUT_MSEC)) != 0) {
LOG_DBG("%s: READ timeout", __func__);
stm32_i2c_reset(dev);
return -EIO;
}
return msg_end(dev, next_msg_flags, __func__);
}
#else /* CONFIG_I2C_STM32_INTERRUPT */
static inline int check_errors(const struct device *dev, const char *funcname)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
if (LL_I2C_IsActiveFlag_AF(i2c)) {
LL_I2C_ClearFlag_AF(i2c);
LOG_DBG("%s: NACK", funcname);
data->current.is_nack = 1U;
goto error;
}
if (LL_I2C_IsActiveFlag_ARLO(i2c)) {
LL_I2C_ClearFlag_ARLO(i2c);
LOG_DBG("%s: ARLO", funcname);
data->current.is_arlo = 1U;
goto error;
}
if (LL_I2C_IsActiveFlag_OVR(i2c)) {
LL_I2C_ClearFlag_OVR(i2c);
LOG_DBG("%s: OVR", funcname);
data->current.is_err = 1U;
goto error;
}
if (LL_I2C_IsActiveFlag_BERR(i2c)) {
LL_I2C_ClearFlag_BERR(i2c);
LOG_DBG("%s: BERR", funcname);
data->current.is_err = 1U;
goto error;
}
return 0;
error:
return -EIO;
}
static int stm32_i2c_wait_timeout(uint16_t *timeout)
{
if (*timeout == 0) {
return 1;
} else {
k_busy_wait(1);
(*timeout)--;
return 0;
}
}
int32_t stm32_i2c_msg_write(const struct device *dev, struct i2c_msg *msg,
uint8_t *next_msg_flags, uint16_t saddr)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
uint32_t len = msg->len;
uint16_t timeout;
uint8_t *buf = msg->buf;
int32_t res;
msg_init(dev, msg, next_msg_flags, saddr, I2C_REQUEST_WRITE);
if (msg->flags & I2C_MSG_RESTART) {
timeout = STM32_I2C_TIMEOUT_USEC;
while (!LL_I2C_IsActiveFlag_SB(i2c)) {
if (stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_GenerateStopCondition(i2c);
data->current.is_err = 1U;
goto end;
}
}
if (I2C_ADDR_10_BITS & data->dev_config) {
uint8_t slave = (((saddr & 0x0300) >> 7) & 0xFF);
uint8_t header = slave | HEADER;
LL_I2C_TransmitData8(i2c, header);
timeout = STM32_I2C_TIMEOUT_USEC;
while (!LL_I2C_IsActiveFlag_ADD10(i2c)) {
if (stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_GenerateStopCondition(i2c);
data->current.is_err = 1U;
goto end;
}
}
slave = data->slave_address & 0xFF;
LL_I2C_TransmitData8(i2c, slave);
} else {
uint8_t slave = (saddr << 1) & 0xFF;
LL_I2C_TransmitData8(i2c, slave | I2C_REQUEST_WRITE);
}
timeout = STM32_I2C_TIMEOUT_USEC;
while (!LL_I2C_IsActiveFlag_ADDR(i2c)) {
if (LL_I2C_IsActiveFlag_AF(i2c) || stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_ClearFlag_AF(i2c);
LL_I2C_GenerateStopCondition(i2c);
data->current.is_nack = 1U;
goto end;
}
}
LL_I2C_ClearFlag_ADDR(i2c);
}
while (len) {
timeout = STM32_I2C_TIMEOUT_USEC;
while (1) {
if (LL_I2C_IsActiveFlag_TXE(i2c)) {
break;
}
if (LL_I2C_IsActiveFlag_AF(i2c) || stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_ClearFlag_AF(i2c);
LL_I2C_GenerateStopCondition(i2c);
data->current.is_nack = 1U;
goto end;
}
}
LL_I2C_TransmitData8(i2c, *buf);
buf++;
len--;
}
timeout = STM32_I2C_TIMEOUT_USEC;
while (!LL_I2C_IsActiveFlag_BTF(i2c)) {
if (stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_GenerateStopCondition(i2c);
data->current.is_err = 1U;
goto end;
}
}
if (msg->flags & I2C_MSG_STOP) {
LL_I2C_GenerateStopCondition(i2c);
}
end:
check_errors(dev, __func__);
res = msg_end(dev, next_msg_flags, __func__);
if (res < 0) {
stm32_i2c_reset(dev);
}
return res;
}
int32_t stm32_i2c_msg_read(const struct device *dev, struct i2c_msg *msg,
uint8_t *next_msg_flags, uint16_t saddr)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
uint32_t len = msg->len;
uint16_t timeout;
uint8_t *buf = msg->buf;
int32_t res;
msg_init(dev, msg, next_msg_flags, saddr, I2C_REQUEST_READ);
if (msg->flags & I2C_MSG_RESTART) {
timeout = STM32_I2C_TIMEOUT_USEC;
while (!LL_I2C_IsActiveFlag_SB(i2c)) {
if (stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_GenerateStopCondition(i2c);
data->current.is_err = 1U;
goto end;
}
}
if (I2C_ADDR_10_BITS & data->dev_config) {
uint8_t slave = (((saddr & 0x0300) >> 7) & 0xFF);
uint8_t header = slave | HEADER;
LL_I2C_TransmitData8(i2c, header);
timeout = STM32_I2C_TIMEOUT_USEC;
while (!LL_I2C_IsActiveFlag_ADD10(i2c)) {
if (stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_GenerateStopCondition(i2c);
data->current.is_err = 1U;
goto end;
}
}
slave = saddr & 0xFF;
LL_I2C_TransmitData8(i2c, slave);
timeout = STM32_I2C_TIMEOUT_USEC;
while (!LL_I2C_IsActiveFlag_ADDR(i2c)) {
if (stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_GenerateStopCondition(i2c);
data->current.is_err = 1U;
goto end;
}
}
LL_I2C_ClearFlag_ADDR(i2c);
stm32_i2c_generate_start_condition(i2c);
timeout = STM32_I2C_TIMEOUT_USEC;
while (!LL_I2C_IsActiveFlag_SB(i2c)) {
if (stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_GenerateStopCondition(i2c);
data->current.is_err = 1U;
goto end;
}
}
header |= I2C_REQUEST_READ;
LL_I2C_TransmitData8(i2c, header);
} else {
uint8_t slave = ((saddr) << 1) & 0xFF;
LL_I2C_TransmitData8(i2c, slave | I2C_REQUEST_READ);
}
timeout = STM32_I2C_TIMEOUT_USEC;
while (!LL_I2C_IsActiveFlag_ADDR(i2c)) {
if (LL_I2C_IsActiveFlag_AF(i2c) || stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_ClearFlag_AF(i2c);
LL_I2C_GenerateStopCondition(i2c);
data->current.is_nack = 1U;
goto end;
}
}
/* ADDR must be cleared before NACK generation. Either in 2 byte reception
* byte 1 will be NACK'ed and slave wont sent the last byte
*/
LL_I2C_ClearFlag_ADDR(i2c);
if (len == 1U) {
/* Single byte reception: enable NACK and set STOP */
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
} else if (len == 2U) {
/* 2-byte reception: enable NACK and set POS */
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
LL_I2C_EnableBitPOS(i2c);
}
}
while (len) {
timeout = STM32_I2C_TIMEOUT_USEC;
while (!LL_I2C_IsActiveFlag_RXNE(i2c)) {
if (stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_GenerateStopCondition(i2c);
data->current.is_err = 1U;
goto end;
}
}
timeout = STM32_I2C_TIMEOUT_USEC;
switch (len) {
case 1:
if (msg->flags & I2C_MSG_STOP) {
LL_I2C_GenerateStopCondition(i2c);
}
len--;
*buf = LL_I2C_ReceiveData8(i2c);
buf++;
break;
case 2:
while (!LL_I2C_IsActiveFlag_BTF(i2c)) {
if (stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_GenerateStopCondition(i2c);
data->current.is_err = 1U;
goto end;
}
}
/*
* Stop condition must be generated before reading the
* last two bytes.
*/
if (msg->flags & I2C_MSG_STOP) {
LL_I2C_GenerateStopCondition(i2c);
}
for (uint32_t counter = 2; counter > 0; counter--) {
len--;
*buf = LL_I2C_ReceiveData8(i2c);
buf++;
}
break;
case 3:
while (!LL_I2C_IsActiveFlag_BTF(i2c)) {
if (stm32_i2c_wait_timeout(&timeout)) {
LL_I2C_GenerateStopCondition(i2c);
data->current.is_err = 1U;
goto end;
}
}
/* Set NACK before reading N-2 byte*/
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
__fallthrough;
default:
len--;
*buf = LL_I2C_ReceiveData8(i2c);
buf++;
}
}
end:
check_errors(dev, __func__);
res = msg_end(dev, next_msg_flags, __func__);
if (res < 0) {
stm32_i2c_reset(dev);
}
return res;
}
#endif /* CONFIG_I2C_STM32_INTERRUPT */
int32_t stm32_i2c_configure_timing(const struct device *dev, uint32_t clock)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
switch (I2C_SPEED_GET(data->dev_config)) {
case I2C_SPEED_STANDARD:
LL_I2C_ConfigSpeed(i2c, clock, 100000, LL_I2C_DUTYCYCLE_2);
break;
case I2C_SPEED_FAST:
LL_I2C_ConfigSpeed(i2c, clock, 400000, LL_I2C_DUTYCYCLE_2);
break;
default:
return -EINVAL;
}
return 0;
}