/**
* @brief This function handles I2C Communication Timeout for specific usage of TXIS flag.
* @param hi2c: Pointer to a I2C_HandleTypeDef structure that contains
* the configuration information for the specified I2C.
* @param Timeout: Timeout duration
* @param Tickstart: Tick start value
* @retval HAL status
*/
static HAL_StatusTypeDef I2C_WaitOnTXISFlagUntilTimeout(I2C_HandleTypeDef *hi2c, uint32_t Timeout, uint32_t Tickstart)
{
while(__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_TXIS) == RESET)
{
/* Check if a NACK is detected */
if(I2C_IsAcknowledgeFailed(hi2c, Timeout, Tickstart) != HAL_OK)
{
return HAL_ERROR;
}
/* Check for the Timeout */
if(Timeout != HAL_MAX_DELAY)
{
if((Timeout == 0)||((HAL_GetTick() - Tickstart) > Timeout))
{
hi2c->ErrorCode |= HAL_I2C_ERROR_TIMEOUT;
hi2c->State= HAL_I2C_STATE_READY;
hi2c->Mode = HAL_I2C_MODE_NONE;
/* Process Unlocked */
__HAL_UNLOCK(hi2c);
return HAL_TIMEOUT;
}
}
}
return HAL_OK;
}
/**
* @brief This function handles I2C Communication Timeout for specific usage of RXNE flag.
* @param hi2c Pointer to a I2C_HandleTypeDef structure that contains
* the configuration information for the specified I2C.
* @param Timeout Timeout duration
* @param Tickstart Tick start value
* @retval HAL status
*/
static HAL_StatusTypeDef I2C_WaitOnRXNEFlagUntilTimeout(I2C_HandleTypeDef *hi2c, uint32_t Timeout, uint32_t Tickstart, uint8_t prev_mode)
{
while (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_RXNE) == RESET)
{
/* Check if a NACK is detected */
if (I2C_IsAcknowledgeFailed(hi2c, Timeout, Tickstart) != HAL_OK)
{
return HAL_NACK;
}
/*
* FIXME: need to re-check if what is supposed to be a RESTART is not also
* triggering a STOP along...
*/
/* Check if a STOPF is detected */
if (prev_mode != HAL_I2C_MODE_MASTER_SEL && __HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_STOPF) == SET)
{
/* Clear STOP Flag */
__HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_STOPF);
/* Clear Configuration Register 2 */
I2C_RESET_CR2(hi2c);
hi2c->ErrorCode = HAL_I2C_ERROR_NONE;
hi2c->State = HAL_I2C_STATE_READY;
hi2c->Mode = HAL_I2C_MODE_NONE;
/* Process Unlocked */
__HAL_UNLOCK(hi2c);
return HAL_ERROR;
}
/* Check for the Timeout */
if ((Timeout == 0U) || ((HAL_GetTick() - Tickstart) > Timeout))
{
hi2c->ErrorCode |= HAL_I2C_ERROR_TIMEOUT;
hi2c->State = HAL_I2C_STATE_READY;
/* Process Unlocked */
__HAL_UNLOCK(hi2c);
return HAL_TIMEOUT;
}
}
return HAL_OK;
}
// this function is based on STM code
int machine_hard_i2c_writeto(mp_obj_base_t *self_in, uint16_t addr, const uint8_t *src, size_t len, bool stop) {
machine_hard_i2c_obj_t *self = (machine_hard_i2c_obj_t*)self_in;
I2C_HandleTypeDef *hi2c = self->pyb->i2c;
uint32_t Timeout = *self->timeout;
/* Init tickstart for timeout management*/
uint32_t tickstart = HAL_GetTick();
#if 0
// TODO: for multi-master, here we could wait for the bus to be free
// we'd need a flag to tell if we were in the middle of a set of transactions
// (ie didn't send a stop bit in the last call)
/* Wait until BUSY flag is reset */
if (!I2C_WaitOnFlagUntilTimeout(hi2c, I2C_FLAG_BUSY, SET, I2C_TIMEOUT_BUSY_FLAG, tickstart)) {
return -MP_EBUSY;
}
#endif
/* Check if the I2C is already enabled */
if ((hi2c->Instance->CR1 & I2C_CR1_PE) != I2C_CR1_PE) {
/* Enable I2C peripheral */
__HAL_I2C_ENABLE(hi2c);
}
/* Disable Pos */
hi2c->Instance->CR1 &= ~I2C_CR1_POS;
/* Send Slave Address */
int ret = send_addr_byte(hi2c, I2C_7BIT_ADD_WRITE(addr << 1), Timeout, tickstart);
if (ret != 0) {
return ret;
}
/* Clear ADDR flag */
__HAL_I2C_CLEAR_ADDRFLAG(hi2c);
int num_acks = 0;
while (len > 0U) {
/* Wait until TXE flag is set */
while (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_TXE) == RESET) {
/* Check if a NACK is detected */
if (I2C_IsAcknowledgeFailed(hi2c)) {
goto nack;
}
/* Check for the Timeout */
if (Timeout != HAL_MAX_DELAY) {
if ((Timeout == 0U) || ((HAL_GetTick()-tickstart) > Timeout)) {
goto timeout;
}
}
}
/* Write data to DR */
hi2c->Instance->DR = *src++;
len--;
/* Wait until BTF flag is set */
while (__HAL_I2C_GET_FLAG(hi2c, I2C_FLAG_BTF) == RESET) {
/* Check if a NACK is detected */
if (I2C_IsAcknowledgeFailed(hi2c)) {
goto nack;
}
/* Check for the Timeout */
if (Timeout != HAL_MAX_DELAY) {
if ((Timeout == 0U) || ((HAL_GetTick()-tickstart) > Timeout)) {
goto timeout;
}
}
}
++num_acks;
}
nack:
/* Generate Stop */
if (stop) {
hi2c->Instance->CR1 |= I2C_CR1_STOP;
}
return num_acks;
timeout:
// timeout, release the bus cleanly
hi2c->Instance->CR1 |= I2C_CR1_STOP;
return -MP_ETIMEDOUT;
}
