BUS_CONFIG_INTR(9)     FreeBSD Kernel Developer's Manual    BUS_CONFIG_INTR(9)

NAME
     BUS_CONFIG_INTR - configure interrupt polarity and trigger mode

SYNOPSIS
     #include <sys/param.h>
     #include <sys/bus.h>

     int
     BUS_CONFIG_INTR(device_t dev, int irq, enum intr_trigger trig,
         enum intr_polarity pol);

DESCRIPTION
     The BUS_CONFIG_INTR() method allows bus or device drivers to provide
     interrupt polarity and trigger mode to parent buses.  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 the
     BUS_CONFIG_INTR() method takes an interrupt number, it is assumed but not
     necessarily required that it is called prior to BUS_SETUP_INTR(9).

     The trig argument can be one of:

     INTR_TRIGGER_CONFORM      The interrupt trigger mode is standard for the
                               bus to which the device is attached.

     INTR_TRIGGER_EDGE         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.

     INTR_TRIGGER_LEVEL        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
                               transitions back.

     The pol argument can be any one of:

     INTR_POLARITY_CONFORM      The interrupt polarity is standard for the bus
                                to which the device is attached.

     INTR_POLARITY_HIGH         The interrupt is activated by a high voltage
                                on the interrupt line.

     INTR_POLARITY_LOW          The interrupt is activated by a low voltage on
                                the interrupt line.

RETURN VALUES
     Zero is returned on success, otherwise an appropriate error is returned.

SEE ALSO
     BUS_SETUP_INTR(9), BUS_TEARDOWN_INTR(9), device(9), driver(9)

HISTORY
     The BUS_CONFIG_INTR() method first appeared in FreeBSD 5.2.

AUTHORS
     This manual page was written by Marcel Moolenaar <marcel@xcllnt.net>.

FreeBSD 13.1-RELEASE-p6        January 15, 2017        FreeBSD 13.1-RELEASE-p6