647 строки
18 KiB
XML
647 строки
18 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
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"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
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<book id="LinuxKernelAPI">
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<bookinfo>
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<title>The Linux Kernel API</title>
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<legalnotice>
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<para>
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This documentation is free software; you can redistribute
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it and/or modify it under the terms of the GNU General Public
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License as published by the Free Software Foundation; either
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version 2 of the License, or (at your option) any later
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version.
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</para>
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<para>
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This program is distributed in the hope that it will be
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useful, but WITHOUT ANY WARRANTY; without even the implied
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warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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See the GNU General Public License for more details.
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</para>
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<para>
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You should have received a copy of the GNU General Public
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License along with this program; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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MA 02111-1307 USA
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</para>
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<para>
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For more details see the file COPYING in the source
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distribution of Linux.
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</para>
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</legalnotice>
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</bookinfo>
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<toc></toc>
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<chapter id="Basics">
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<title>Driver Basics</title>
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<sect1><title>Driver Entry and Exit points</title>
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!Iinclude/linux/init.h
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</sect1>
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<sect1><title>Atomic and pointer manipulation</title>
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!Iinclude/asm-i386/atomic.h
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!Iinclude/asm-i386/unaligned.h
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</sect1>
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<sect1><title>Delaying, scheduling, and timer routines</title>
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!Iinclude/linux/sched.h
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!Ekernel/sched.c
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!Ekernel/timer.c
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</sect1>
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<sect1><title>High-resolution timers</title>
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!Iinclude/linux/ktime.h
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!Iinclude/linux/hrtimer.h
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!Ekernel/hrtimer.c
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</sect1>
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<sect1><title>Workqueues and Kevents</title>
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!Ekernel/workqueue.c
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</sect1>
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<sect1><title>Internal Functions</title>
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!Ikernel/exit.c
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!Ikernel/signal.c
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!Iinclude/linux/kthread.h
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!Ekernel/kthread.c
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</sect1>
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<sect1><title>Kernel objects manipulation</title>
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<!--
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X!Iinclude/linux/kobject.h
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-->
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!Elib/kobject.c
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</sect1>
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<sect1><title>Kernel utility functions</title>
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!Iinclude/linux/kernel.h
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!Ekernel/printk.c
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!Ekernel/panic.c
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!Ekernel/sys.c
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!Ekernel/rcupdate.c
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</sect1>
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<sect1><title>Device Resource Management</title>
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!Edrivers/base/devres.c
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</sect1>
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</chapter>
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<chapter id="adt">
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<title>Data Types</title>
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<sect1><title>Doubly Linked Lists</title>
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!Iinclude/linux/list.h
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</sect1>
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</chapter>
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|
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<chapter id="libc">
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<title>Basic C Library Functions</title>
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<para>
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When writing drivers, you cannot in general use routines which are
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from the C Library. Some of the functions have been found generally
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useful and they are listed below. The behaviour of these functions
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may vary slightly from those defined by ANSI, and these deviations
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are noted in the text.
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</para>
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|
|
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<sect1><title>String Conversions</title>
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!Ilib/vsprintf.c
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!Elib/vsprintf.c
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</sect1>
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|
<sect1><title>String Manipulation</title>
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|
<!-- All functions are exported at now
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X!Ilib/string.c
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-->
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!Elib/string.c
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</sect1>
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<sect1><title>Bit Operations</title>
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!Iinclude/asm-i386/bitops.h
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</sect1>
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</chapter>
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<chapter id="kernel-lib">
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<title>Basic Kernel Library Functions</title>
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<para>
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The Linux kernel provides more basic utility functions.
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</para>
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<sect1><title>Bitmap Operations</title>
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!Elib/bitmap.c
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!Ilib/bitmap.c
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</sect1>
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<sect1><title>Command-line Parsing</title>
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!Elib/cmdline.c
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</sect1>
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<sect1><title>CRC Functions</title>
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!Elib/crc16.c
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!Elib/crc32.c
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!Elib/crc-ccitt.c
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</sect1>
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</chapter>
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<chapter id="mm">
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<title>Memory Management in Linux</title>
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<sect1><title>The Slab Cache</title>
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!Iinclude/linux/slab.h
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!Emm/slab.c
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</sect1>
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<sect1><title>User Space Memory Access</title>
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!Iinclude/asm-i386/uaccess.h
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!Earch/i386/lib/usercopy.c
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</sect1>
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<sect1><title>More Memory Management Functions</title>
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!Iinclude/linux/rmap.h
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!Emm/readahead.c
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!Emm/filemap.c
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!Emm/memory.c
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!Emm/vmalloc.c
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!Imm/page_alloc.c
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!Emm/mempool.c
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!Emm/page-writeback.c
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!Emm/truncate.c
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</sect1>
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</chapter>
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<chapter id="ipc">
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<title>Kernel IPC facilities</title>
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<sect1><title>IPC utilities</title>
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!Iipc/util.c
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</sect1>
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</chapter>
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<chapter id="kfifo">
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<title>FIFO Buffer</title>
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<sect1><title>kfifo interface</title>
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!Iinclude/linux/kfifo.h
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!Ekernel/kfifo.c
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</sect1>
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</chapter>
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<chapter id="relayfs">
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<title>relay interface support</title>
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<para>
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Relay interface support
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is designed to provide an efficient mechanism for tools and
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facilities to relay large amounts of data from kernel space to
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user space.
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</para>
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<sect1><title>relay interface</title>
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!Ekernel/relay.c
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!Ikernel/relay.c
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</sect1>
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</chapter>
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<chapter id="netcore">
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<title>Linux Networking</title>
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<sect1><title>Networking Base Types</title>
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!Iinclude/linux/net.h
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</sect1>
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<sect1><title>Socket Buffer Functions</title>
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!Iinclude/linux/skbuff.h
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!Iinclude/net/sock.h
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!Enet/socket.c
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!Enet/core/skbuff.c
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!Enet/core/sock.c
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!Enet/core/datagram.c
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!Enet/core/stream.c
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</sect1>
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<sect1><title>Socket Filter</title>
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!Enet/core/filter.c
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</sect1>
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<sect1><title>Generic Network Statistics</title>
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!Iinclude/linux/gen_stats.h
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!Enet/core/gen_stats.c
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!Enet/core/gen_estimator.c
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</sect1>
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<sect1><title>SUN RPC subsystem</title>
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<!-- The !D functionality is not perfect, garbage has to be protected by comments
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!Dnet/sunrpc/sunrpc_syms.c
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-->
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!Enet/sunrpc/xdr.c
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!Enet/sunrpc/svcsock.c
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!Enet/sunrpc/sched.c
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</sect1>
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</chapter>
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<chapter id="netdev">
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<title>Network device support</title>
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<sect1><title>Driver Support</title>
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!Enet/core/dev.c
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!Enet/ethernet/eth.c
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!Iinclude/linux/etherdevice.h
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!Edrivers/net/phy/phy.c
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!Idrivers/net/phy/phy.c
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!Edrivers/net/phy/phy_device.c
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!Idrivers/net/phy/phy_device.c
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!Edrivers/net/phy/mdio_bus.c
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!Idrivers/net/phy/mdio_bus.c
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<!-- FIXME: Removed for now since no structured comments in source
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X!Enet/core/wireless.c
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-->
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</sect1>
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<sect1><title>Synchronous PPP</title>
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!Edrivers/net/wan/syncppp.c
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</sect1>
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</chapter>
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<chapter id="modload">
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<title>Module Support</title>
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<sect1><title>Module Loading</title>
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!Ekernel/kmod.c
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</sect1>
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<sect1><title>Inter Module support</title>
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<para>
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Refer to the file kernel/module.c for more information.
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</para>
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<!-- FIXME: Removed for now since no structured comments in source
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X!Ekernel/module.c
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-->
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</sect1>
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</chapter>
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<chapter id="hardware">
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<title>Hardware Interfaces</title>
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<sect1><title>Interrupt Handling</title>
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!Ekernel/irq/manage.c
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</sect1>
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<sect1><title>DMA Channels</title>
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!Ekernel/dma.c
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</sect1>
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<sect1><title>Resources Management</title>
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!Ikernel/resource.c
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!Ekernel/resource.c
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</sect1>
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<sect1><title>MTRR Handling</title>
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!Earch/i386/kernel/cpu/mtrr/main.c
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</sect1>
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<sect1><title>PCI Support Library</title>
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!Edrivers/pci/pci.c
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!Edrivers/pci/pci-driver.c
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!Edrivers/pci/remove.c
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!Edrivers/pci/pci-acpi.c
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!Edrivers/pci/search.c
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!Edrivers/pci/msi.c
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!Edrivers/pci/bus.c
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<!-- FIXME: Removed for now since no structured comments in source
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X!Edrivers/pci/hotplug.c
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-->
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!Edrivers/pci/probe.c
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!Edrivers/pci/rom.c
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</sect1>
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<sect1><title>PCI Hotplug Support Library</title>
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!Edrivers/pci/hotplug/pci_hotplug_core.c
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</sect1>
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<sect1><title>MCA Architecture</title>
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<sect2><title>MCA Device Functions</title>
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<para>
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Refer to the file arch/i386/kernel/mca.c for more information.
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</para>
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<!-- FIXME: Removed for now since no structured comments in source
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X!Earch/i386/kernel/mca.c
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-->
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</sect2>
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<sect2><title>MCA Bus DMA</title>
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!Iinclude/asm-i386/mca_dma.h
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</sect2>
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</sect1>
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</chapter>
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<chapter id="firmware">
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<title>Firmware Interfaces</title>
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<sect1><title>DMI Interfaces</title>
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!Edrivers/firmware/dmi_scan.c
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</sect1>
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<sect1><title>EDD Interfaces</title>
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!Idrivers/firmware/edd.c
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</sect1>
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</chapter>
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<chapter id="security">
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<title>Security Framework</title>
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!Esecurity/security.c
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</chapter>
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<chapter id="audit">
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<title>Audit Interfaces</title>
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!Ekernel/audit.c
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!Ikernel/auditsc.c
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!Ikernel/auditfilter.c
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</chapter>
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<chapter id="accounting">
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<title>Accounting Framework</title>
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!Ikernel/acct.c
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</chapter>
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<chapter id="pmfuncs">
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<title>Power Management</title>
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!Ekernel/power/pm.c
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</chapter>
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<chapter id="devdrivers">
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<title>Device drivers infrastructure</title>
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<sect1><title>Device Drivers Base</title>
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<!--
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X!Iinclude/linux/device.h
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-->
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!Edrivers/base/driver.c
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!Edrivers/base/core.c
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!Edrivers/base/class.c
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!Edrivers/base/firmware_class.c
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!Edrivers/base/transport_class.c
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!Edrivers/base/dmapool.c
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|
<!-- Cannot be included, because
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attribute_container_add_class_device_adapter
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and attribute_container_classdev_to_container
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exceed allowed 44 characters maximum
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X!Edrivers/base/attribute_container.c
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-->
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!Edrivers/base/sys.c
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<!--
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X!Edrivers/base/interface.c
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-->
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!Edrivers/base/platform.c
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!Edrivers/base/bus.c
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</sect1>
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<sect1><title>Device Drivers Power Management</title>
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!Edrivers/base/power/main.c
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!Edrivers/base/power/resume.c
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!Edrivers/base/power/suspend.c
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</sect1>
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<sect1><title>Device Drivers ACPI Support</title>
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<!-- Internal functions only
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X!Edrivers/acpi/sleep/main.c
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X!Edrivers/acpi/sleep/wakeup.c
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X!Edrivers/acpi/motherboard.c
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X!Edrivers/acpi/bus.c
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-->
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!Edrivers/acpi/scan.c
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!Idrivers/acpi/scan.c
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<!-- No correct structured comments
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X!Edrivers/acpi/pci_bind.c
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-->
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</sect1>
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<sect1><title>Device drivers PnP support</title>
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!Edrivers/pnp/core.c
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<!-- No correct structured comments
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X!Edrivers/pnp/system.c
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-->
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!Edrivers/pnp/card.c
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!Edrivers/pnp/driver.c
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!Edrivers/pnp/manager.c
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!Edrivers/pnp/support.c
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</sect1>
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</chapter>
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<chapter id="blkdev">
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<title>Block Devices</title>
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!Eblock/ll_rw_blk.c
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</chapter>
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<chapter id="chrdev">
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<title>Char devices</title>
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!Efs/char_dev.c
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</chapter>
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<chapter id="miscdev">
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<title>Miscellaneous Devices</title>
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!Edrivers/char/misc.c
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</chapter>
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|
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<chapter id="parportdev">
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<title>Parallel Port Devices</title>
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!Iinclude/linux/parport.h
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!Edrivers/parport/ieee1284.c
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!Edrivers/parport/share.c
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!Idrivers/parport/daisy.c
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</chapter>
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|
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<chapter id="message_devices">
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<title>Message-based devices</title>
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<sect1><title>Fusion message devices</title>
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!Edrivers/message/fusion/mptbase.c
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!Idrivers/message/fusion/mptbase.c
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!Edrivers/message/fusion/mptscsih.c
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!Idrivers/message/fusion/mptscsih.c
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!Idrivers/message/fusion/mptctl.c
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!Idrivers/message/fusion/mptspi.c
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!Idrivers/message/fusion/mptfc.c
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!Idrivers/message/fusion/mptlan.c
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</sect1>
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<sect1><title>I2O message devices</title>
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!Iinclude/linux/i2o.h
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!Idrivers/message/i2o/core.h
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!Edrivers/message/i2o/iop.c
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!Idrivers/message/i2o/iop.c
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!Idrivers/message/i2o/config-osm.c
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!Edrivers/message/i2o/exec-osm.c
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!Idrivers/message/i2o/exec-osm.c
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!Idrivers/message/i2o/bus-osm.c
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!Edrivers/message/i2o/device.c
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!Idrivers/message/i2o/device.c
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!Idrivers/message/i2o/driver.c
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!Idrivers/message/i2o/pci.c
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!Idrivers/message/i2o/i2o_block.c
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!Idrivers/message/i2o/i2o_scsi.c
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!Idrivers/message/i2o/i2o_proc.c
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|
</sect1>
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|
</chapter>
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|
|
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<chapter id="snddev">
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|
<title>Sound Devices</title>
|
|
!Iinclude/sound/core.h
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!Esound/sound_core.c
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|
!Iinclude/sound/pcm.h
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|
!Esound/core/pcm.c
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|
!Esound/core/device.c
|
|
!Esound/core/info.c
|
|
!Esound/core/rawmidi.c
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|
!Esound/core/sound.c
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|
!Esound/core/memory.c
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|
!Esound/core/pcm_memory.c
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|
!Esound/core/init.c
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|
!Esound/core/isadma.c
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|
!Esound/core/control.c
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|
!Esound/core/pcm_lib.c
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|
!Esound/core/hwdep.c
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|
!Esound/core/pcm_native.c
|
|
!Esound/core/memalloc.c
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|
<!-- FIXME: Removed for now since no structured comments in source
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X!Isound/sound_firmware.c
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|
-->
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|
</chapter>
|
|
|
|
<chapter id="uart16x50">
|
|
<title>16x50 UART Driver</title>
|
|
!Iinclude/linux/serial_core.h
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|
!Edrivers/serial/serial_core.c
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!Edrivers/serial/8250.c
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</chapter>
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|
|
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<chapter id="z85230">
|
|
<title>Z85230 Support Library</title>
|
|
!Edrivers/net/wan/z85230.c
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|
</chapter>
|
|
|
|
<chapter id="fbdev">
|
|
<title>Frame Buffer Library</title>
|
|
|
|
<para>
|
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The frame buffer drivers depend heavily on four data structures.
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These structures are declared in include/linux/fb.h. They are
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fb_info, fb_var_screeninfo, fb_fix_screeninfo and fb_monospecs.
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The last three can be made available to and from userland.
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|
</para>
|
|
|
|
<para>
|
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fb_info defines the current state of a particular video card.
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Inside fb_info, there exists a fb_ops structure which is a
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|
collection of needed functions to make fbdev and fbcon work.
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fb_info is only visible to the kernel.
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|
</para>
|
|
|
|
<para>
|
|
fb_var_screeninfo is used to describe the features of a video card
|
|
that are user defined. With fb_var_screeninfo, things such as
|
|
depth and the resolution may be defined.
|
|
</para>
|
|
|
|
<para>
|
|
The next structure is fb_fix_screeninfo. This defines the
|
|
properties of a card that are created when a mode is set and can't
|
|
be changed otherwise. A good example of this is the start of the
|
|
frame buffer memory. This "locks" the address of the frame buffer
|
|
memory, so that it cannot be changed or moved.
|
|
</para>
|
|
|
|
<para>
|
|
The last structure is fb_monospecs. In the old API, there was
|
|
little importance for fb_monospecs. This allowed for forbidden things
|
|
such as setting a mode of 800x600 on a fix frequency monitor. With
|
|
the new API, fb_monospecs prevents such things, and if used
|
|
correctly, can prevent a monitor from being cooked. fb_monospecs
|
|
will not be useful until kernels 2.5.x.
|
|
</para>
|
|
|
|
<sect1><title>Frame Buffer Memory</title>
|
|
!Edrivers/video/fbmem.c
|
|
</sect1>
|
|
<!--
|
|
<sect1><title>Frame Buffer Console</title>
|
|
X!Edrivers/video/console/fbcon.c
|
|
</sect1>
|
|
-->
|
|
<sect1><title>Frame Buffer Colormap</title>
|
|
!Edrivers/video/fbcmap.c
|
|
</sect1>
|
|
<!-- FIXME:
|
|
drivers/video/fbgen.c has no docs, which stuffs up the sgml. Comment
|
|
out until somebody adds docs. KAO
|
|
<sect1><title>Frame Buffer Generic Functions</title>
|
|
X!Idrivers/video/fbgen.c
|
|
</sect1>
|
|
KAO -->
|
|
<sect1><title>Frame Buffer Video Mode Database</title>
|
|
!Idrivers/video/modedb.c
|
|
!Edrivers/video/modedb.c
|
|
</sect1>
|
|
<sect1><title>Frame Buffer Macintosh Video Mode Database</title>
|
|
!Edrivers/video/macmodes.c
|
|
</sect1>
|
|
<sect1><title>Frame Buffer Fonts</title>
|
|
<para>
|
|
Refer to the file drivers/video/console/fonts.c for more information.
|
|
</para>
|
|
<!-- FIXME: Removed for now since no structured comments in source
|
|
X!Idrivers/video/console/fonts.c
|
|
-->
|
|
</sect1>
|
|
</chapter>
|
|
|
|
<chapter id="input_subsystem">
|
|
<title>Input Subsystem</title>
|
|
!Iinclude/linux/input.h
|
|
!Edrivers/input/input.c
|
|
!Edrivers/input/ff-core.c
|
|
!Edrivers/input/ff-memless.c
|
|
</chapter>
|
|
|
|
<chapter id="spi">
|
|
<title>Serial Peripheral Interface (SPI)</title>
|
|
<para>
|
|
SPI is the "Serial Peripheral Interface", widely used with
|
|
embedded systems because it is a simple and efficient
|
|
interface: basically a multiplexed shift register.
|
|
Its three signal wires hold a clock (SCK, often in the range
|
|
of 1-20 MHz), a "Master Out, Slave In" (MOSI) data line, and
|
|
a "Master In, Slave Out" (MISO) data line.
|
|
SPI is a full duplex protocol; for each bit shifted out the
|
|
MOSI line (one per clock) another is shifted in on the MISO line.
|
|
Those bits are assembled into words of various sizes on the
|
|
way to and from system memory.
|
|
An additional chipselect line is usually active-low (nCS);
|
|
four signals are normally used for each peripheral, plus
|
|
sometimes an interrupt.
|
|
</para>
|
|
<para>
|
|
The SPI bus facilities listed here provide a generalized
|
|
interface to declare SPI busses and devices, manage them
|
|
according to the standard Linux driver model, and perform
|
|
input/output operations.
|
|
At this time, only "master" side interfaces are supported,
|
|
where Linux talks to SPI peripherals and does not implement
|
|
such a peripheral itself.
|
|
(Interfaces to support implementing SPI slaves would
|
|
necessarily look different.)
|
|
</para>
|
|
<para>
|
|
The programming interface is structured around two kinds of driver,
|
|
and two kinds of device.
|
|
A "Controller Driver" abstracts the controller hardware, which may
|
|
be as simple as a set of GPIO pins or as complex as a pair of FIFOs
|
|
connected to dual DMA engines on the other side of the SPI shift
|
|
register (maximizing throughput). Such drivers bridge between
|
|
whatever bus they sit on (often the platform bus) and SPI, and
|
|
expose the SPI side of their device as a
|
|
<structname>struct spi_master</structname>.
|
|
SPI devices are children of that master, represented as a
|
|
<structname>struct spi_device</structname> and manufactured from
|
|
<structname>struct spi_board_info</structname> descriptors which
|
|
are usually provided by board-specific initialization code.
|
|
A <structname>struct spi_driver</structname> is called a
|
|
"Protocol Driver", and is bound to a spi_device using normal
|
|
driver model calls.
|
|
</para>
|
|
<para>
|
|
The I/O model is a set of queued messages. Protocol drivers
|
|
submit one or more <structname>struct spi_message</structname>
|
|
objects, which are processed and completed asynchronously.
|
|
(There are synchronous wrappers, however.) Messages are
|
|
built from one or more <structname>struct spi_transfer</structname>
|
|
objects, each of which wraps a full duplex SPI transfer.
|
|
A variety of protocol tweaking options are needed, because
|
|
different chips adopt very different policies for how they
|
|
use the bits transferred with SPI.
|
|
</para>
|
|
!Iinclude/linux/spi/spi.h
|
|
!Fdrivers/spi/spi.c spi_register_board_info
|
|
!Edrivers/spi/spi.c
|
|
</chapter>
|
|
|
|
</book>
|