STM32F4_I2C_SR2
ret = readl_relaxed_poll_timeout(i2c_dev->base + STM32F4_I2C_SR2,
readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2);
readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2);
readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2);
readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2);
readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2);