'\" t
.\"     Title: struct w1_bus_master
.\"    Author: 
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: March 2017
.\"    Manual: W1 API internal to the kernel
.\"    Source: Kernel Hackers Manual 4.10.7
.\"  Language: English
.\"
.TH "STRUCT W1_BUS_MASTER" "9" "March 2017" "Kernel Hackers Manual 4\&.10\&" "W1 API internal to the kernel"
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.SH "NAME"
struct_w1_bus_master \- operations available on a bus master
.SH "SYNOPSIS"
.sp
.nf
struct w1_bus_master {
  void * data;
  u8 (* read_bit) (void *);
  void (* write_bit) (void *, u8);
  u8 (* touch_bit) (void *, u8);
  u8 (* read_byte) (void *);
  void (* write_byte) (void *, u8);
  u8 (* read_block) (void *, u8 *, int);
  void (* write_block) (void *, const u8 *, int);
  u8 (* triplet) (void *, u8);
  u8 (* reset_bus) (void *);
  u8 (* set_pullup) (void *, int);
  void (* search) (void *, struct w1_master *,u8, w1_slave_found_callback);
};  
.fi
.SH "MEMBERS"
.PP
data
.RS 4
the first parameter in all the functions below
.RE
.PP
read_bit
.RS 4
Sample the line level
\fIreturn\fR
the level read (0 or 1)
.RE
.PP
write_bit
.RS 4
Sets the line level
.RE
.PP
touch_bit
.RS 4
the lowest\-level function for devices that really support the 1\-wire protocol\&. touch_bit(0) = write\-0 cycle touch_bit(1) = write\-1 / read cycle
\fIreturn\fR
the bit read (0 or 1)
.RE
.PP
read_byte
.RS 4
Reads a bytes\&. Same as 8 touch_bit(1) calls\&.
\fIreturn\fR
the byte read
.RE
.PP
write_byte
.RS 4
Writes a byte\&. Same as 8 touch_bit(x) calls\&.
.RE
.PP
read_block
.RS 4
Same as a series of
\fBread_byte\fR
calls
\fIreturn\fR
the number of bytes read
.RE
.PP
write_block
.RS 4
Same as a series of
\fBwrite_byte\fR
calls
.RE
.PP
triplet
.RS 4
Combines two reads and a smart write for ROM searches
\fIreturn\fR
bit0=Id bit1=comp_id bit2=dir_taken
.RE
.PP
reset_bus
.RS 4
long write\-0 with a read for the presence pulse detection
\fIreturn\fR
\-1=Error, 0=Device present, 1=No device present
.RE
.PP
set_pullup
.RS 4
Put out a strong pull\-up pulse of the specified duration\&.
\fIreturn\fR
\-1=Error, 0=completed
.RE
.PP
search
.RS 4
Really nice hardware can handles the different types of ROM search w1_master* is passed to the slave found callback\&. u8 is search_type, W1_SEARCH or W1_ALARM_SEARCH
.RE
.SH "NOTE"
.PP
read_bit and write_bit are very low level functions and should only be used with hardware that doesn\*(Aqt really support 1\-wire operations, like a parallel/serial port\&. Either define read_bit and write_bit OR define, at minimum, touch_bit and reset_bus\&.
.SH "AUTHOR"
.PP
\fBDavid Fries\fR <\&David@Fries.net\&>
.RS 4
Author.
.RE
.SH "COPYRIGHT"
.br