i2c: stm32f7: fix first byte to send in slave mode

The slave-interface documentation [1] states "the bus driver should
transmit the first byte" upon I2C_SLAVE_READ_REQUESTED slave event:
- 'val': backend returns first byte to be sent
The driver currently ignores the 1st byte to send on this event.

[1] https://www.kernel.org/doc/Documentation/i2c/slave-interface

Fixes: 60d609f30d ("i2c: i2c-stm32f7: Add slave support")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Fabrice Gasnier 2019-09-30 17:28:01 +02:00 committed by Wolfram Sang
parent 62931ac2f9
commit 02e64276c6

View file

@ -1192,6 +1192,8 @@ static void stm32f7_i2c_slave_start(struct stm32f7_i2c_dev *i2c_dev)
STM32F7_I2C_CR1_TXIE; STM32F7_I2C_CR1_TXIE;
stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask); stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);
/* Write 1st data byte */
writel_relaxed(value, base + STM32F7_I2C_TXDR);
} else { } else {
/* Notify i2c slave that new write transfer is starting */ /* Notify i2c slave that new write transfer is starting */
i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value); i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value);