Copyright (c) 2003 Marcel Moolenaar All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or ...
NAMEBUS_CONFIG_INTR - configure interrupt polarity and trigger mode
SYNOPSISIn sys/param.h In sys/bus.h Ft int Fo BUS_CONFIG_INTR Fa device_t dev int irq enum intr_trigger trig enum intr_polarity pol Fc
DESCRIPTIONThe Fn BUS_CONFIG_INTR 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 the Fn BUS_CONFIG_INTR method takes an interrupt number, it is assumed but not necessarily required that it is called prior to BUS_SETUP_INTR9.
The Fa trig argument can be one of:
- The interrupt trigger mode is standard for the bus to which the device is attached.
- 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 transitions back.
The Fa pol argument can be any one of:
- The interrupt polarity is standard for the bus to which the device is attached.
- The interrupt is activated by a high voltage on the interrupt line.
- The interrupt is activated by a low voltage on the interrupt line.