Why is there no error-passive interrupt on FlexCAN?
There are interrupts for active, warning (which isn't even standard), and bus-off, but not passive. How come?
The current driver implementation in the linux kernel polls esr1 for state changes whenever an rx- or error interrupt is received. If the bus is open (not connected), the error state in the driver is not updated, so the state is out of sync with what's happening in the device.