zephyr/drivers/i2c/i2c_ll_stm32_v2.c

378 lines
8.6 KiB
C

/*
* Copyright (c) 2016 BayLibre, SAS
* Copyright (c) 2017 Linaro Ltd
*
* SPDX-License-Identifier: Apache-2.0
*
* I2C Driver for: STM32F0, STM32F3, STM32F7, STM32L0 and STM32L4
*
*/
#include <clock_control/stm32_clock_control.h>
#include <clock_control.h>
#include <misc/util.h>
#include <kernel.h>
#include <board.h>
#include <errno.h>
#include <i2c.h>
#include "i2c_ll_stm32.h"
#define SYS_LOG_LEVEL CONFIG_SYS_LOG_I2C_LEVEL
#include <logging/sys_log.h>
static inline void msg_init(struct device *dev, struct i2c_msg *msg,
u8_t *next_msg_flags, u16_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;
if (LL_I2C_IsEnabledReloadMode(i2c)) {
LL_I2C_SetTransferSize(i2c, msg->len);
} else {
if (I2C_ADDR_10_BITS & data->dev_config) {
LL_I2C_SetMasterAddressingMode(i2c,
LL_I2C_ADDRESSING_MODE_10BIT);
LL_I2C_SetSlaveAddr(i2c, (uint32_t) slave);
} else {
LL_I2C_SetMasterAddressingMode(i2c,
LL_I2C_ADDRESSING_MODE_7BIT);
LL_I2C_SetSlaveAddr(i2c, (uint32_t) slave << 1);
}
if (!(msg->flags & I2C_MSG_STOP) && next_msg_flags &&
!(*next_msg_flags & I2C_MSG_RESTART)) {
LL_I2C_EnableReloadMode(i2c);
} else {
LL_I2C_DisableReloadMode(i2c);
}
LL_I2C_DisableAutoEndMode(i2c);
LL_I2C_SetTransferRequest(i2c, transfer);
LL_I2C_SetTransferSize(i2c, msg->len);
LL_I2C_GenerateStartCondition(i2c);
}
}
#ifdef CONFIG_I2C_STM32_INTERRUPT
void stm32_i2c_event_isr(void *arg)
{
const struct i2c_stm32_config *cfg = DEV_CFG((struct device *)arg);
struct i2c_stm32_data *data = DEV_DATA((struct device *)arg);
I2C_TypeDef *i2c = cfg->i2c;
if (data->current.len) {
/* Interrupts for sending/receiving next byte */
if (data->current.is_write && LL_I2C_IsActiveFlag_TXIS(i2c)) {
/* Send next byte */
LL_I2C_TransmitData8(i2c, *data->current.buf);
} else if (!(data->current.is_write) &&
LL_I2C_IsActiveFlag_RXNE(i2c)) {
/* Receive next byte */
*data->current.buf = LL_I2C_ReceiveData8(i2c);
} else {
goto error;
}
data->current.buf++;
data->current.len--;
if (!data->current.len) {
LL_I2C_EnableIT_TC(i2c);
}
} else {
/* Interrupts to process end of message */
if (LL_I2C_IsActiveFlag_TC(i2c) ||
LL_I2C_IsActiveFlag_TCR(i2c)) {
/* Interrupt after last byte of message
* was transferred
*/
LL_I2C_DisableIT_TC(i2c);
LL_I2C_DisableIT_RX(i2c);
/* Issue stop condition if necessary */
if (data->current.msg->flags & I2C_MSG_STOP) {
LL_I2C_GenerateStopCondition(i2c);
LL_I2C_EnableIT_STOP(i2c);
} else {
k_sem_give(&data->device_sync_sem);
}
} else if (LL_I2C_IsActiveFlag_STOP(i2c)) {
/* Interrupt after stop condition was
* successfully issued
*/
LL_I2C_DisableIT_STOP(i2c);
LL_I2C_ClearFlag_STOP(i2c);
LL_I2C_DisableReloadMode(i2c);
k_sem_give(&data->device_sync_sem);
} else {
goto error;
}
}
return;
error:
LL_I2C_DisableIT_TX(i2c);
LL_I2C_DisableIT_RX(i2c);
data->current.is_err = 1;
k_sem_give(&data->device_sync_sem);
}
#ifndef CONFIG_I2C_STM32_COMBINED_INTERRUPT
void stm32_i2c_error_isr(void *arg)
{
const struct i2c_stm32_config *cfg = DEV_CFG((struct device *)arg);
struct i2c_stm32_data *data = DEV_DATA((struct device *)arg);
I2C_TypeDef *i2c = cfg->i2c;
if (LL_I2C_IsActiveFlag_NACK(i2c)) {
LL_I2C_ClearFlag_NACK(i2c);
data->current.is_nack = 1;
} else {
data->current.is_err = 1;
}
k_sem_give(&data->device_sync_sem);
}
#endif
#ifdef CONFIG_I2C_STM32_COMBINED_INTERRUPT
void stm32_i2c_combined_isr(void *arg)
{
const struct i2c_stm32_config *cfg = DEV_CFG((struct device *)arg);
struct i2c_stm32_data *data = DEV_DATA((struct device *)arg);
I2C_TypeDef *i2c = cfg->i2c;
if (LL_I2C_IsActiveFlag_NACK(i2c)) {
LL_I2C_ClearFlag_NACK(i2c);
data->current.is_nack = 1;
k_sem_give(&data->device_sync_sem);
} else {
stm32_i2c_event_isr(arg);
}
}
#endif
int stm32_i2c_msg_write(struct device *dev, struct i2c_msg *msg,
u8_t *next_msg_flags, uint16_t slave)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
data->current.len = msg->len;
data->current.buf = msg->buf;
data->current.is_write = 1;
data->current.is_nack = 0;
data->current.is_err = 0;
data->current.msg = msg;
msg_init(dev, msg, next_msg_flags, slave, LL_I2C_REQUEST_WRITE);
LL_I2C_EnableIT_TX(i2c);
LL_I2C_EnableIT_NACK(i2c);
k_sem_take(&data->device_sync_sem, K_FOREVER);
LL_I2C_DisableIT_TX(i2c);
LL_I2C_DisableIT_NACK(i2c);
if (data->current.is_nack || data->current.is_err) {
goto error;
}
return 0;
error:
if (data->current.is_nack) {
SYS_LOG_DBG("%s: NACK", __func__);
data->current.is_nack = 0;
}
if (data->current.is_err) {
SYS_LOG_DBG("%s: ERR %d", __func__,
data->current.is_err);
data->current.is_err = 0;
}
return -EIO;
}
int stm32_i2c_msg_read(struct device *dev, struct i2c_msg *msg,
u8_t *next_msg_flags, uint16_t slave)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
data->current.len = msg->len;
data->current.buf = msg->buf;
data->current.is_write = 0;
data->current.is_err = 0;
data->current.msg = msg;
msg_init(dev, msg, next_msg_flags, slave, LL_I2C_REQUEST_READ);
LL_I2C_EnableIT_RX(i2c);
k_sem_take(&data->device_sync_sem, K_FOREVER);
LL_I2C_DisableIT_RX(i2c);
if (data->current.is_err) {
goto error;
}
return 0;
error:
SYS_LOG_DBG("%s: ERR %d", __func__, data->current.is_err);
data->current.is_err = 0;
return -EIO;
}
#else /* !CONFIG_I2C_STM32_INTERRUPT */
static inline void msg_done(struct device *dev, unsigned int current_msg_flags)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
I2C_TypeDef *i2c = cfg->i2c;
/* Wait for transfer to complete */
while (!LL_I2C_IsActiveFlag_TC(i2c) && !LL_I2C_IsActiveFlag_TCR(i2c)) {
;
}
/* Issue stop condition if necessary */
if (current_msg_flags & I2C_MSG_STOP) {
LL_I2C_GenerateStopCondition(i2c);
while (!LL_I2C_IsActiveFlag_STOP(i2c)) {
;
}
LL_I2C_ClearFlag_STOP(i2c);
LL_I2C_DisableReloadMode(i2c);
}
}
int stm32_i2c_msg_write(struct device *dev, struct i2c_msg *msg,
u8_t *next_msg_flags, uint16_t slave)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
I2C_TypeDef *i2c = cfg->i2c;
unsigned int len = 0;
u8_t *buf = msg->buf;
msg_init(dev, msg, next_msg_flags, slave, LL_I2C_REQUEST_WRITE);
len = msg->len;
while (len) {
while (1) {
if (LL_I2C_IsActiveFlag_TXIS(i2c)) {
break;
}
if (LL_I2C_IsActiveFlag_NACK(i2c)) {
goto error;
}
}
LL_I2C_TransmitData8(i2c, *buf);
buf++;
len--;
}
msg_done(dev, msg->flags);
return 0;
error:
LL_I2C_ClearFlag_NACK(i2c);
SYS_LOG_DBG("%s: NACK", __func__);
return -EIO;
}
int stm32_i2c_msg_read(struct device *dev, struct i2c_msg *msg,
u8_t *next_msg_flags, uint16_t slave)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
I2C_TypeDef *i2c = cfg->i2c;
unsigned int len = 0;
u8_t *buf = msg->buf;
msg_init(dev, msg, next_msg_flags, slave, LL_I2C_REQUEST_READ);
len = msg->len;
while (len) {
while (!LL_I2C_IsActiveFlag_RXNE(i2c)) {
;
}
*buf = LL_I2C_ReceiveData8(i2c);
buf++;
len--;
}
msg_done(dev, msg->flags);
return 0;
}
#endif
int stm32_i2c_configure_timing(struct device *dev, u32_t clock)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
u32_t i2c_hold_time_min, i2c_setup_time_min;
u32_t i2c_h_min_time, i2c_l_min_time;
u32_t presc = 1;
u32_t timing = 0;
switch (I2C_SPEED_GET(data->dev_config)) {
case I2C_SPEED_STANDARD:
i2c_h_min_time = 4000;
i2c_l_min_time = 4700;
i2c_hold_time_min = 500;
i2c_setup_time_min = 1250;
break;
case I2C_SPEED_FAST:
i2c_h_min_time = 600;
i2c_l_min_time = 1300;
i2c_hold_time_min = 375;
i2c_setup_time_min = 500;
break;
default:
return -EINVAL;
}
/* Calculate period until prescaler matches */
do {
u32_t t_presc = clock / presc;
u32_t ns_presc = NSEC_PER_SEC / t_presc;
u32_t sclh = i2c_h_min_time / ns_presc;
u32_t scll = i2c_l_min_time / ns_presc;
u32_t sdadel = i2c_hold_time_min / ns_presc;
u32_t scldel = i2c_setup_time_min / ns_presc;
if ((sclh - 1) > 255 || (scll - 1) > 255) {
++presc;
continue;
}
if (sdadel > 15 || (scldel - 1) > 15) {
++presc;
continue;
}
timing = __LL_I2C_CONVERT_TIMINGS(presc - 1,
scldel - 1, sdadel, sclh - 1, scll - 1);
break;
} while (presc < 16);
if (presc >= 16) {
SYS_LOG_DBG("I2C:failed to find prescaler value");
return -EINVAL;
}
LL_I2C_SetTiming(i2c, timing);
return 0;
}