Commit e2444509 authored by Jean Nanchen's avatar Jean Nanchen Committed by Anas Nashif
Browse files

drivers: i2c: stm32: add timeout to avoid infinite loop 



Fix issue where STM32 I2C LL driver could block forever when SDA and SCL
are shorted and interrupts are disabled (CONFIG_I2C_STM32_INTERRUPT=n).

Added timeouts to all blocking wait loops in the STM32 LL I2C driver to
avoid indefinite blocking.

Fixes #88506

Signed-off-by: default avatarJean Nanchen <jean.nanchen@hevs.ch>
(cherry picked from commit 2066b8c7)
parent b45ca8df

drivers/i2c/i2c_ll_stm32_v2.c

+41 −0
Original line number Diff line number Diff line
@@ -736,17 +736,26 @@ static inline int msg_done(const struct device *dev, 
{

	const struct i2c_stm32_config *cfg = dev->config;

	I2C_TypeDef *i2c = cfg->i2c;

	int64_t start_time = k_uptime_get();



	/* Wait for transfer to complete */

	while (!LL_I2C_IsActiveFlag_TC(i2c) && !LL_I2C_IsActiveFlag_TCR(i2c)) {

		if (check_errors(dev, __func__)) {

			return -EIO;

		}

		if ((k_uptime_get() - start_time) >

		    STM32_I2C_TRANSFER_TIMEOUT_MSEC) {

			return -ETIMEDOUT;

		}

	}

	/* Issue stop condition if necessary */

	if (current_msg_flags & I2C_MSG_STOP) {

		LL_I2C_GenerateStopCondition(i2c);

		while (!LL_I2C_IsActiveFlag_STOP(i2c)) {

			if ((k_uptime_get() - start_time) >

			    STM32_I2C_TRANSFER_TIMEOUT_MSEC) {

				return -ETIMEDOUT;

			}

		}



		LL_I2C_ClearFlag_STOP(i2c);
@@ -763,6 +772,7 @@ static int stm32_i2c_msg_write(const struct device *dev, struct i2c_msg *msg, 
	I2C_TypeDef *i2c = cfg->i2c;

	unsigned int len = 0U;

	uint8_t *buf = msg->buf;

	int64_t start_time = k_uptime_get();



	msg_init(dev, msg, next_msg_flags, slave, LL_I2C_REQUEST_WRITE);
@@ -776,6 +786,11 @@ static int stm32_i2c_msg_write(const struct device *dev, struct i2c_msg *msg, 
			if (check_errors(dev, __func__)) {

				return -EIO;

			}



			if ((k_uptime_get() - start_time) >

			    STM32_I2C_TRANSFER_TIMEOUT_MSEC) {

				return -ETIMEDOUT;

			}

		}



		LL_I2C_TransmitData8(i2c, *buf);
@@ -793,6 +808,7 @@ static int stm32_i2c_msg_read(const struct device *dev, struct i2c_msg *msg, 
	I2C_TypeDef *i2c = cfg->i2c;

	unsigned int len = 0U;

	uint8_t *buf = msg->buf;

	int64_t start_time = k_uptime_get();



	msg_init(dev, msg, next_msg_flags, slave, LL_I2C_REQUEST_READ);
@@ -802,6 +818,10 @@ static int stm32_i2c_msg_read(const struct device *dev, struct i2c_msg *msg, 
			if (check_errors(dev, __func__)) {

				return -EIO;

			}

			if ((k_uptime_get() - start_time) >

			    STM32_I2C_TRANSFER_TIMEOUT_MSEC) {

				return -ETIMEDOUT;

			}

		}



		*buf = LL_I2C_ReceiveData8(i2c);
@@ -1172,5 +1192,26 @@ int stm32_i2c_transaction(const struct device *dev, 
		msg.len = rest;

	} while (rest > 0U);



#ifndef CONFIG_I2C_STM32_INTERRUPT

	struct i2c_stm32_data *data = dev->data;



	if (ret == -ETIMEDOUT) {

		if (LL_I2C_IsEnabledReloadMode(i2c)) {

			LL_I2C_DisableReloadMode(i2c);

		}

#if defined(CONFIG_I2C_TARGET)

		data->master_active = false;

		if (!data->slave_attached && !data->smbalert_active) {

			LL_I2C_Disable(i2c);

		}

#else

		if (!data->smbalert_active) {

			LL_I2C_Disable(i2c);

		}

#endif

		return -EIO;

	}

#endif /* !CONFIG_I2C_STM32_INTERRUPT */



	return ret;

}

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