freebsd-dev/sys/dev/ow/own_if.m
Warner Losh ae1f3df434 New 1-Wire bus implementation. 1-Wire controller is abstracted, though
only gpiobus configured via FDT is supported. Bus enumeration is
supported. Devices are created for each device found. 1-Wire
temperature controllers are supported, but other drivers could be
written. Temperatures are polled and reported via a sysctl.  Errors
are reported via sysctl counters. Mis-wired bus detection is included
for more trouble shooting. See ow(4), owc(4) and ow_temp(4) for
details of what's supported and known issues.

This has been tested on Raspberry Pi-B, Pi2 and Beagle Bone Black
with up to 7 devices.

Differential Revision: https://reviews.freebsd.org/D2956
Relnotes: yes
MFC after: 2 weeks
Reviewed by: loos@ (with many insightful comments)
2015-08-27 23:33:38 +00:00

79 lines
2.3 KiB
Objective-C

#-
# Copyright (c) 2015 M. Warner Losh <imp@freebsd.org>
# 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 <dev/ow/ow.h>
INTERFACE own;
#
# Dallas Semiconductor 1-Wire bus network and transport layer (own)
#
# See Maxim Application Note AN937: Book of iButton Standards for the
# 1-Wire protocol specification.
# http://pdfserv.maximintegrated.com/en/an/AN937.pdf
#
# Note: 1-Wire is a registered trademark of Maxim Integrated Products, Inc.
#
#
# Send a command up the stack.
#
METHOD int send_command {
device_t ndev; /* Network (bus) level device */
device_t pdev; /* Device to send command for */
struct ow_cmd *cmd; /* Pointer to filled in command */
};
#
# Grab exclusive use of the bus (advisory)
#
METHOD int acquire_bus {
device_t ndev;
device_t pdev;
int how;
};
#
# Release exclusive use of the bus (advisory)
#
METHOD void release_bus {
device_t ndev;
device_t pdev;
};
#
# Compute a CRC for a given range of bytes
#
METHOD uint8_t crc {
device_t ndev;
device_t pdev;
uint8_t *buffer;
size_t len;
};