'\" t
.\"     Title: w1_search
.\"    Author: 
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: June 2017
.\"    Manual: W1 API internal to the kernel
.\"    Source: Kernel Hackers Manual 4.11.3
.\"  Language: English
.\"
.TH "W1_SEARCH" "9" "June 2017" "Kernel Hackers Manual 4\&.11\&" "W1 API internal to the kernel"
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.SH "NAME"
w1_search \- Performs a ROM Search & registers any devices found\&.
.SH "SYNOPSIS"
.HP \w'void\ w1_search('u
.BI "void w1_search(struct\ w1_master\ *\ " "dev" ", u8\ " "search_type" ", w1_slave_found_callback\ " "cb" ");"
.SH "ARGUMENTS"
.PP
\fIstruct w1_master * dev\fR
.RS 4
The master device to search
.RE
.PP
\fIu8 search_type\fR
.RS 4
W1_SEARCH to search all devices, or W1_ALARM_SEARCH to return only devices in the alarmed state
.RE
.PP
\fIw1_slave_found_callback cb\fR
.RS 4
Function to call when a device is found
.RE
.SH "DESCRIPTION"
.PP
The 1\-wire search is a simple binary tree search\&. For each bit of the address, we read two bits and write one bit\&. The bit written will put to sleep all devies that don\*(Aqt match that bit\&. When the two reads differ, the direction choice is obvious\&. When both bits are 0, we must choose a path to take\&. When we can scan all 64 bits without having to choose a path, we are done\&.
.PP
See
\(lqApplication note 187 1\-wire search algorithm\(rq
at www\&.maxim\-ic\&.com
.SH "AUTHOR"
.PP
\fBDavid Fries\fR <\&David@Fries.net\&>
.RS 4
Author.
.RE
.SH "COPYRIGHT"
.br