freebsd-skq/sys/dev/ow/owll.h
imp 05c9f26dff 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

55 lines
2.2 KiB
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 unmodified, 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 ``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 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.
*
* $FreeBSD$
*/
#ifndef DEV_OW_OWLL_H
#define DEV_OW_OWLL_H 1
/*
* Generalized parameters for the mode of operation in the bus. All units
* are in nanoseconds, and assume that all timings are < 4s.
* See owll_if.m for timings, and refer to AN937 for details.
*/
struct ow_timing
{
uint32_t t_slot; /* Slot time */
uint32_t t_low0; /* Time low for a 0 bit. */
uint32_t t_low1; /* Time low for a 1 bit. */
uint32_t t_lowr; /* Time slave holds line down per bit */
uint32_t t_release; /* Time after t_rdv to float high */
uint32_t t_rec; /* After sample before M low */
uint32_t t_rdv; /* Time to poll the bit after M low */
uint32_t t_rstl; /* Time M low on reset */
uint32_t t_rsth; /* Time M high on reset */
uint32_t t_pdl; /* Time S low on reset */
uint32_t t_pdh; /* Time R high after M low on reset */
};
#include "owll_if.h"
#endif /* DEV_OW_OWLL_H */