freebsd-skq/sys/kern/serdev_if.m
Marcel Moolenaar 845652dd28 MFp4: Add the ipend() method to the serdev I/F to allow umbrella
drivers to obtain pending interrupt status from subordinate
	drivers.
2006-04-23 22:12:39 +00:00

95 lines
3.5 KiB
Objective-C

#-
# Copyright (c) 2006 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 other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
# $FreeBSD$
#
#include <sys/bus.h>
#include <sys/serial.h>
# The serdev interface is used by umbrella drivers and children thereof to
# establish a more intimate relationship, necessary for efficient handling
# of multiple (concurrent) serial communication channels. Examples include
# serial communications controller (SCC) drivers, multi-I/O adapter drivers
# and intelligent multi-port serial drivers. Methods specifically deal
# with interrupt handling and configuration. Conceptually, the umbrella
# driver is responsible for the overall operation of the hardware and uses
# child drivers to handle each individual channel.
# The serdev interface is intended to inherit the device interface.
INTERFACE serdev;
# Default implementations of some methods.
CODE {
static serdev_intr_t *
default_ihand(device_t dev, int ipend)
{
return (NULL);
}
static int
default_ipend(device_t dev)
{
return (-1);
}
static int
default_sysdev(device_t dev)
{
return (0);
}
};
# ihand() - Query serial device interrupt handler.
# This method is called by the umbrella driver to obtain function pointers
# to interrupt handlers for each individual interrupt source. This allows
# the umbralla driver to control the servicing of interrupts between the
# different channels in the most flexible way.
METHOD serdev_intr_t* ihand {
device_t dev;
int ipend;
} DEFAULT default_ihand;
# ipend() - Query pending interrupt status.
# This method is called by the umbrella driver to obtain interrupt status
# for the UART in question. This allows the umbrella driver to build a
# matrix and service the interrupts in the most flexible way by calling
# interrupt handlers collected with the ihand() method.
METHOD int ipend {
device_t dev;
} DEFAULT default_ipend;
# sysdev() - Query system device status
# This method may be called by the umbrella driver for each child driver
# to establish if a particular channel and mode is currently being used
# for system specific usage. If this is the case, the hardware is not
# reset and the channel will not change its operation mode.
# The return value is !0 if the channel and mode are used for a system
# device and 0 otherwise.
METHOD int sysdev {
device_t dev;
} DEFAULT default_sysdev;