On Thu, Apr 11, 2024 at 08:58:45AM +0300, Tony Lindgren wrote: > We are seeing start_tx being called after port shutdown as noted by Jiri. > This happens because we are missing the startup and shutdown related > functions for the serial base port. > > Let's fix the issue by adding startup and shutdown functions for the > serial base port to block tx flushing for the serial base port when the > port is not in use. I tried to test this on the current max3100.c driver, but this doesn't change anything to me. The scenario is that: - load the driver with dyndbg on - attach device (I have done it via SSDT overlay) - call `stty -F /dev/ttyMAX0` to see it works - call `stty -F /dev/ttyMAX0 115200` to setup speed - test case: a) run `cat /proc/interrupts > /dev/ttyMAX0` b) press Ctrl + C c) (most cases) press Ctrl + C - repeat the previous step several times The outcome (with or without this change) is that - it repeatedly calls start_tx() - most of the times as you may notice it requires actually to press Ctrl + C _twice to stop the queueing The testing environment is the tty-next + this patch. I admit that max3100 may be buggy, but this change doesn't fix anything for it. -- With Best Regards, Andy Shevchenko
