zephyr/drivers/i2c/i2c_ll_stm32_v1.c

500 lines
11 KiB
C

/*
* 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 <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>
#define I2C_REQUEST_WRITE 0x00
#define I2C_REQUEST_READ 0x01
#define HEADER 0xF0
#ifdef CONFIG_I2C_STM32_INTERRUPT
static inline void handle_sb(I2C_TypeDef *i2c, struct i2c_stm32_data *data)
{
u16_t saddr = data->slave_address;
u8_t slave;
if (I2C_ADDR_10_BITS & data->dev_config) {
slave = (((saddr & 0x0300) >> 7) & 0xFF);
u8_t header = slave | HEADER;
if (data->current.is_restart == 0) {
data->current.is_restart = 1;
} else {
header |= I2C_REQUEST_READ;
data->current.is_restart = 0;
}
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);
}
}
static inline void handle_addr(I2C_TypeDef *i2c, struct i2c_stm32_data *data)
{
if (I2C_ADDR_10_BITS & data->dev_config) {
if (!data->current.is_write && data->current.is_restart) {
data->current.is_restart = 0;
LL_I2C_ClearFlag_ADDR(i2c);
LL_I2C_GenerateStartCondition(i2c);
return;
}
}
if (!data->current.is_write) {
if (data->current.len == 1) {
/* Single byte reception: enable NACK and clear POS */
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
} else if (data->current.len == 2) {
/* 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(I2C_TypeDef *i2c, struct i2c_stm32_data *data)
{
if (data->current.len) {
data->current.len--;
if (data->current.len == 0) {
/*
* 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(I2C_TypeDef *i2c, struct i2c_stm32_data *data)
{
if (data->current.len > 0) {
switch (data->current.len) {
case 1:
/* 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:
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++;
}
}
}
static inline void handle_btf(I2C_TypeDef *i2c, struct i2c_stm32_data *data)
{
if (data->current.is_write) {
handle_txe(i2c, data);
} else {
u32_t counter = 0;
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 = 2; 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(i2c, data);
}
}
}
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 (LL_I2C_IsActiveFlag_SB(i2c)) {
handle_sb(i2c, data);
} else if (LL_I2C_IsActiveFlag_ADD10(i2c)) {
LL_I2C_TransmitData8(i2c, data->slave_address);
} else if (LL_I2C_IsActiveFlag_ADDR(i2c)) {
handle_addr(i2c, data);
} else if (LL_I2C_IsActiveFlag_BTF(i2c)) {
handle_btf(i2c, data);
} else if (LL_I2C_IsActiveFlag_TXE(i2c) && data->current.is_write) {
handle_txe(i2c, data);
} else if (LL_I2C_IsActiveFlag_RXNE(i2c) && !data->current.is_write) {
handle_rxne(i2c, data);
}
}
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_AF(i2c)) {
LL_I2C_ClearFlag_AF(i2c);
data->current.is_nack = 1;
k_sem_give(&data->device_sync_sem);
return;
}
data->current.is_err = 1;
k_sem_give(&data->device_sync_sem);
}
s32_t stm32_i2c_msg_write(struct device *dev, struct i2c_msg *msg,
u8_t *next_msg_flags, u16_t saddr)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
s32_t ret = 0;
ARG_UNUSED(next_msg_flags);
data->current.len = msg->len;
data->current.buf = msg->buf;
data->current.flags = msg->flags;
data->current.is_restart = 0;
data->current.is_write = 1;
data->current.is_nack = 0;
data->current.is_err = 0;
data->slave_address = saddr;
LL_I2C_EnableIT_EVT(i2c);
LL_I2C_EnableIT_ERR(i2c);
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_ACK);
if (msg->flags & I2C_MSG_RESTART) {
LL_I2C_GenerateStartCondition(i2c);
}
LL_I2C_EnableIT_BUF(i2c);
k_sem_take(&data->device_sync_sem, K_FOREVER);
LL_I2C_DisableIT_BUF(i2c);
if (data->current.is_nack || data->current.is_err) {
if (data->current.is_nack)
SYS_LOG_DBG("%s: NACK", __func__);
if (data->current.is_err)
SYS_LOG_DBG("%s: ERR %d", __func__,
data->current.is_err);
data->current.is_nack = 0;
data->current.is_err = 0;
ret = -EIO;
}
LL_I2C_DisableIT_EVT(i2c);
LL_I2C_DisableIT_ERR(i2c);
return ret;
}
s32_t stm32_i2c_msg_read(struct device *dev, struct i2c_msg *msg,
u8_t *next_msg_flags, u16_t saddr)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
s32_t ret = 0;
ARG_UNUSED(next_msg_flags);
data->current.len = msg->len;
data->current.buf = msg->buf;
data->current.flags = msg->flags;
data->current.is_restart = 0;
data->current.is_write = 0;
data->current.is_err = 0;
data->slave_address = saddr;
LL_I2C_EnableIT_EVT(i2c);
LL_I2C_EnableIT_ERR(i2c);
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_ACK);
LL_I2C_GenerateStartCondition(i2c);
LL_I2C_EnableIT_BUF(i2c);
k_sem_take(&data->device_sync_sem, K_FOREVER);
LL_I2C_DisableIT_BUF(i2c);
if (data->current.is_err) {
SYS_LOG_DBG("%s: ERR %d", __func__, data->current.is_err);
data->current.is_err = 0;
ret = -EIO;
}
LL_I2C_DisableIT_EVT(i2c);
LL_I2C_DisableIT_ERR(i2c);
return ret;
}
#else
s32_t stm32_i2c_msg_write(struct device *dev, struct i2c_msg *msg,
u8_t *next_msg_flags, u16_t saddr)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
u32_t len = msg->len;
u8_t *buf = msg->buf;
ARG_UNUSED(next_msg_flags);
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_ACK);
if (msg->flags & I2C_MSG_RESTART) {
LL_I2C_GenerateStartCondition(i2c);
while (!LL_I2C_IsActiveFlag_SB(i2c)) {
;
}
if (I2C_ADDR_10_BITS & data->dev_config) {
u8_t slave = (((saddr & 0x0300) >> 7) & 0xFF);
u8_t header = slave | HEADER;
LL_I2C_TransmitData8(i2c, header);
while (!LL_I2C_IsActiveFlag_ADD10(i2c)) {
;
}
slave = data->slave_address & 0xFF;
LL_I2C_TransmitData8(i2c, slave);
} else {
u8_t slave = (saddr << 1) & 0xFF;
LL_I2C_TransmitData8(i2c, slave | I2C_REQUEST_WRITE);
}
while (!LL_I2C_IsActiveFlag_ADDR(i2c)) {
;
}
LL_I2C_ClearFlag_ADDR(i2c);
}
while (len) {
while (1) {
if (LL_I2C_IsActiveFlag_TXE(i2c)) {
break;
}
if (LL_I2C_IsActiveFlag_AF(i2c)) {
LL_I2C_ClearFlag_AF(i2c);
SYS_LOG_DBG("%s: NACK", __func__);
return -EIO;
}
};
LL_I2C_TransmitData8(i2c, *buf);
buf++;
len--;
}
while (!LL_I2C_IsActiveFlag_BTF(i2c)) {
;
}
if (msg->flags & I2C_MSG_STOP) {
LL_I2C_GenerateStopCondition(i2c);
}
return 0;
}
s32_t stm32_i2c_msg_read(struct device *dev, struct i2c_msg *msg,
u8_t *next_msg_flags, u16_t saddr)
{
const struct i2c_stm32_config *cfg = DEV_CFG(dev);
struct i2c_stm32_data *data = DEV_DATA(dev);
I2C_TypeDef *i2c = cfg->i2c;
u32_t len = msg->len;
u8_t *buf = msg->buf;
ARG_UNUSED(next_msg_flags);
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_ACK);
if (msg->flags & I2C_MSG_RESTART) {
LL_I2C_GenerateStartCondition(i2c);
while (!LL_I2C_IsActiveFlag_SB(i2c)) {
;
}
if (I2C_ADDR_10_BITS & data->dev_config) {
u8_t slave = (((saddr & 0x0300) >> 7) & 0xFF);
u8_t header = slave | HEADER;
LL_I2C_TransmitData8(i2c, header);
while (!LL_I2C_IsActiveFlag_ADD10(i2c)) {
;
}
slave = saddr & 0xFF;
LL_I2C_TransmitData8(i2c, slave);
while (!LL_I2C_IsActiveFlag_ADDR(i2c)) {
;
}
LL_I2C_ClearFlag_ADDR(i2c);
LL_I2C_GenerateStartCondition(i2c);
while (!LL_I2C_IsActiveFlag_SB(i2c)) {
;
}
header |= I2C_REQUEST_READ;
LL_I2C_TransmitData8(i2c, header);
} else {
u8_t slave = ((saddr) << 1) & 0xFF;
LL_I2C_TransmitData8(i2c, slave | I2C_REQUEST_READ);
}
while (!LL_I2C_IsActiveFlag_ADDR(i2c)) {
;
}
if (len == 1) {
/* Single byte reception: enable NACK and set STOP */
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
} else if (len == 2) {
/* 2-byte reception: enable NACK and set POS */
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
LL_I2C_EnableBitPOS(i2c);
}
LL_I2C_ClearFlag_ADDR(i2c);
}
while (len) {
while (!LL_I2C_IsActiveFlag_RXNE(i2c)) {
;
}
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)) {
;
}
/*
* Stop condition must be generated before reading the
* last two bytes.
*/
if (msg->flags & I2C_MSG_STOP) {
LL_I2C_GenerateStopCondition(i2c);
}
for (u32_t counter = 2; counter > 0; counter--) {
len--;
*buf = LL_I2C_ReceiveData8(i2c);
buf++;
}
break;
case 3:
while (!LL_I2C_IsActiveFlag_BTF(i2c)) {
;
}
/* Set NACK before reading N-2 byte*/
LL_I2C_AcknowledgeNextData(i2c, LL_I2C_NACK);
/* Fall through */
default:
len--;
*buf = LL_I2C_ReceiveData8(i2c);
buf++;
}
}
return 0;
}
#endif
s32_t 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;
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;
}