configure interrupt polarity and trigger mode
, int irq
enum intr_trigger trig
enum intr_polarity pol
() method allows bus or
device drivers to provide interrupt polarity and trigger mode to parent
busses. This typically bubbles all the way up to the root bus (e.g. nexus)
where the necessary actions are taken to actually program the hardware. Since
() method takes an
interrupt number, it is assumed but not necessarily required that it is called
prior to BUS_SETUP_INTR(9)
argument can be one of:
- The interrupt trigger mode is standard for the bus to which the device is
- The interrupt is edge triggered. This means that the interrupt is raised
by the rising edge of the signal on the interrupt line. The signal
typically reverts to the original state so as to cause a spike.
- The interrupt is level triggered. This means that the interrupt is raised
when the signal on the interrupt line transitions and remains unchanged
after that until the interrupt has been serviced, after which the signal
argument can be any one of:
- The interrupt polarity is standard for the bus to which the device is
- The interrupt is activated by a high voltage on the interrupt line.
- The interrupt is activated by a low voltage on the interrupt line.
Zero is returned on success, otherwise an appropriate error is returned.
() method first appeared
in FreeBSD 5.2
This manual page was written by Marcel