drivers: i2c_stm32_v2: fix assert in i2c event isr
For systems where the CPU / NVIC bus are considerably
faster than the peripheral bus used for I2C, there is
a risk that the isr handler returns before I2C controller
had time to clear its interrupt status flags
This would cause immediate re-entry to isr handler
which begins read from ISR register.
During time it take to re-enter and read from ISR register,
flags had time to be cleared
The isr handler expects that a flag is set, and in this case
when its not, an assert is triggered
The solution here is to make a dummy read from the ISR register before
returning from isr handler, this forces CPU to wait as long as needed
to ensure all writes to the I2C peripheral are completed
Fixes issue #97904
Signed-off-by: Erik Andersson <erian747@gmail.com>
1 file changed
