pnp: fix kernel-doc warnings
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / Documentation / DocBook / kernel-api.tmpl
CommitLineData
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1<?xml version="1.0" encoding="UTF-8"?>
2<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
3 "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
4
5<book id="LinuxKernelAPI">
6 <bookinfo>
7 <title>The Linux Kernel API</title>
8
9 <legalnotice>
10 <para>
11 This documentation is free software; you can redistribute
12 it and/or modify it under the terms of the GNU General Public
13 License as published by the Free Software Foundation; either
14 version 2 of the License, or (at your option) any later
15 version.
16 </para>
17
18 <para>
19 This program is distributed in the hope that it will be
20 useful, but WITHOUT ANY WARRANTY; without even the implied
21 warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
22 See the GNU General Public License for more details.
23 </para>
24
25 <para>
26 You should have received a copy of the GNU General Public
27 License along with this program; if not, write to the Free
28 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
29 MA 02111-1307 USA
30 </para>
31
32 <para>
33 For more details see the file COPYING in the source
34 distribution of Linux.
35 </para>
36 </legalnotice>
37 </bookinfo>
38
39<toc></toc>
40
41 <chapter id="Basics">
42 <title>Driver Basics</title>
43 <sect1><title>Driver Entry and Exit points</title>
44!Iinclude/linux/init.h
45 </sect1>
46
47 <sect1><title>Atomic and pointer manipulation</title>
48!Iinclude/asm-i386/atomic.h
49!Iinclude/asm-i386/unaligned.h
50 </sect1>
51
1da177e4 52 <sect1><title>Delaying, scheduling, and timer routines</title>
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53!Iinclude/linux/sched.h
54!Ekernel/sched.c
55!Ekernel/timer.c
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56 </sect1>
57 <sect1><title>High-resolution timers</title>
58!Iinclude/linux/ktime.h
59!Iinclude/linux/hrtimer.h
60!Ekernel/hrtimer.c
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61 </sect1>
62 <sect1><title>Workqueues and Kevents</title>
63!Ekernel/workqueue.c
1da177e4 64 </sect1>
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65 <sect1><title>Internal Functions</title>
66!Ikernel/exit.c
67!Ikernel/signal.c
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68!Iinclude/linux/kthread.h
69!Ekernel/kthread.c
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70 </sect1>
71
72 <sect1><title>Kernel objects manipulation</title>
73<!--
74X!Iinclude/linux/kobject.h
75-->
76!Elib/kobject.c
77 </sect1>
78
79 <sect1><title>Kernel utility functions</title>
80!Iinclude/linux/kernel.h
ddad86c2 81!Ekernel/printk.c
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82!Ekernel/panic.c
83!Ekernel/sys.c
84!Ekernel/rcupdate.c
85 </sect1>
86
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87 <sect1><title>Device Resource Management</title>
88!Edrivers/base/devres.c
89 </sect1>
90
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91 </chapter>
92
93 <chapter id="adt">
94 <title>Data Types</title>
95 <sect1><title>Doubly Linked Lists</title>
96!Iinclude/linux/list.h
97 </sect1>
98 </chapter>
99
100 <chapter id="libc">
101 <title>Basic C Library Functions</title>
102
103 <para>
104 When writing drivers, you cannot in general use routines which are
105 from the C Library. Some of the functions have been found generally
106 useful and they are listed below. The behaviour of these functions
107 may vary slightly from those defined by ANSI, and these deviations
108 are noted in the text.
109 </para>
110
111 <sect1><title>String Conversions</title>
112!Ilib/vsprintf.c
113!Elib/vsprintf.c
114 </sect1>
115 <sect1><title>String Manipulation</title>
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116<!-- All functions are exported at now
117X!Ilib/string.c
118 -->
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119!Elib/string.c
120 </sect1>
121 <sect1><title>Bit Operations</title>
122!Iinclude/asm-i386/bitops.h
123 </sect1>
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124 </chapter>
125
126 <chapter id="kernel-lib">
127 <title>Basic Kernel Library Functions</title>
128
129 <para>
130 The Linux kernel provides more basic utility functions.
131 </para>
132
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133 <sect1><title>Bitmap Operations</title>
134!Elib/bitmap.c
135!Ilib/bitmap.c
136 </sect1>
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137
138 <sect1><title>Command-line Parsing</title>
139!Elib/cmdline.c
140 </sect1>
2f72100c 141
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142 <sect1 id="crc"><title>CRC Functions</title>
143!Elib/crc7.c
2f72100c 144!Elib/crc16.c
ad241528 145!Elib/crc-itu-t.c
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146!Elib/crc32.c
147!Elib/crc-ccitt.c
148 </sect1>
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149 </chapter>
150
151 <chapter id="mm">
152 <title>Memory Management in Linux</title>
153 <sect1><title>The Slab Cache</title>
800590f5 154!Iinclude/linux/slab.h
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155!Emm/slab.c
156 </sect1>
157 <sect1><title>User Space Memory Access</title>
158!Iinclude/asm-i386/uaccess.h
8f2709b5 159!Earch/i386/lib/usercopy.c
1da177e4 160 </sect1>
4dc3b16b 161 <sect1><title>More Memory Management Functions</title>
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162!Emm/readahead.c
163!Emm/filemap.c
164!Emm/memory.c
165!Emm/vmalloc.c
88ca3b94 166!Imm/page_alloc.c
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167!Emm/mempool.c
168!Emm/page-writeback.c
169!Emm/truncate.c
170 </sect1>
171 </chapter>
172
173
174 <chapter id="ipc">
175 <title>Kernel IPC facilities</title>
176
177 <sect1><title>IPC utilities</title>
178!Iipc/util.c
179 </sect1>
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180 </chapter>
181
182 <chapter id="kfifo">
183 <title>FIFO Buffer</title>
184 <sect1><title>kfifo interface</title>
185!Iinclude/linux/kfifo.h
186!Ekernel/kfifo.c
187 </sect1>
188 </chapter>
189
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190 <chapter id="relayfs">
191 <title>relay interface support</title>
192
193 <para>
194 Relay interface support
195 is designed to provide an efficient mechanism for tools and
196 facilities to relay large amounts of data from kernel space to
197 user space.
198 </para>
199
200 <sect1><title>relay interface</title>
201!Ekernel/relay.c
202!Ikernel/relay.c
203 </sect1>
204 </chapter>
205
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206 <chapter id="netcore">
207 <title>Linux Networking</title>
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208 <sect1><title>Networking Base Types</title>
209!Iinclude/linux/net.h
210 </sect1>
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211 <sect1><title>Socket Buffer Functions</title>
212!Iinclude/linux/skbuff.h
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213!Iinclude/net/sock.h
214!Enet/socket.c
1da177e4 215!Enet/core/skbuff.c
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216!Enet/core/sock.c
217!Enet/core/datagram.c
218!Enet/core/stream.c
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219 </sect1>
220 <sect1><title>Socket Filter</title>
221!Enet/core/filter.c
222 </sect1>
223 <sect1><title>Generic Network Statistics</title>
224!Iinclude/linux/gen_stats.h
225!Enet/core/gen_stats.c
226!Enet/core/gen_estimator.c
227 </sect1>
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228 <sect1><title>SUN RPC subsystem</title>
229<!-- The !D functionality is not perfect, garbage has to be protected by comments
230!Dnet/sunrpc/sunrpc_syms.c
231-->
232!Enet/sunrpc/xdr.c
233!Enet/sunrpc/svcsock.c
234!Enet/sunrpc/sched.c
235 </sect1>
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236 </chapter>
237
238 <chapter id="netdev">
239 <title>Network device support</title>
240 <sect1><title>Driver Support</title>
241!Enet/core/dev.c
c2da8aca 242!Enet/ethernet/eth.c
461ddf3b 243!Iinclude/linux/etherdevice.h
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244!Edrivers/net/phy/phy.c
245!Idrivers/net/phy/phy.c
246!Edrivers/net/phy/phy_device.c
247!Idrivers/net/phy/phy_device.c
248!Edrivers/net/phy/mdio_bus.c
249!Idrivers/net/phy/mdio_bus.c
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250<!-- FIXME: Removed for now since no structured comments in source
251X!Enet/core/wireless.c
252-->
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253 </sect1>
254 <sect1><title>Synchronous PPP</title>
255!Edrivers/net/wan/syncppp.c
256 </sect1>
257 </chapter>
258
259 <chapter id="modload">
260 <title>Module Support</title>
261 <sect1><title>Module Loading</title>
262!Ekernel/kmod.c
263 </sect1>
264 <sect1><title>Inter Module support</title>
265 <para>
266 Refer to the file kernel/module.c for more information.
267 </para>
268<!-- FIXME: Removed for now since no structured comments in source
269X!Ekernel/module.c
270-->
271 </sect1>
272 </chapter>
273
274 <chapter id="hardware">
275 <title>Hardware Interfaces</title>
276 <sect1><title>Interrupt Handling</title>
8f2709b5 277!Ekernel/irq/manage.c
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278 </sect1>
279
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280 <sect1><title>DMA Channels</title>
281!Ekernel/dma.c
282 </sect1>
283
4dc3b16b 284 <sect1><title>Resources Management</title>
2b54960b 285!Ikernel/resource.c
e1ca66d1 286!Ekernel/resource.c
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287 </sect1>
288
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289 <sect1><title>MTRR Handling</title>
290!Earch/i386/kernel/cpu/mtrr/main.c
291 </sect1>
b0ef371e 292
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293 <sect1><title>PCI Support Library</title>
294!Edrivers/pci/pci.c
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295!Edrivers/pci/pci-driver.c
296!Edrivers/pci/remove.c
297!Edrivers/pci/pci-acpi.c
d75763d2 298!Edrivers/pci/search.c
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299!Edrivers/pci/msi.c
300!Edrivers/pci/bus.c
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301<!-- FIXME: Removed for now since no structured comments in source
302X!Edrivers/pci/hotplug.c
303-->
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304!Edrivers/pci/probe.c
305!Edrivers/pci/rom.c
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306 </sect1>
307 <sect1><title>PCI Hotplug Support Library</title>
308!Edrivers/pci/hotplug/pci_hotplug_core.c
309 </sect1>
310 <sect1><title>MCA Architecture</title>
311 <sect2><title>MCA Device Functions</title>
312 <para>
313 Refer to the file arch/i386/kernel/mca.c for more information.
314 </para>
315<!-- FIXME: Removed for now since no structured comments in source
316X!Earch/i386/kernel/mca.c
317-->
318 </sect2>
319 <sect2><title>MCA Bus DMA</title>
320!Iinclude/asm-i386/mca_dma.h
321 </sect2>
322 </sect1>
323 </chapter>
324
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325 <chapter id="firmware">
326 <title>Firmware Interfaces</title>
327 <sect1><title>DMI Interfaces</title>
328!Edrivers/firmware/dmi_scan.c
329 </sect1>
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330 <sect1><title>EDD Interfaces</title>
331!Idrivers/firmware/edd.c
332 </sect1>
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333 </chapter>
334
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335 <chapter id="security">
336 <title>Security Framework</title>
337!Esecurity/security.c
338 </chapter>
339
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340 <chapter id="audit">
341 <title>Audit Interfaces</title>
342!Ekernel/audit.c
343!Ikernel/auditsc.c
344!Ikernel/auditfilter.c
345 </chapter>
346
347 <chapter id="accounting">
348 <title>Accounting Framework</title>
349!Ikernel/acct.c
350 </chapter>
351
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352 <chapter id="pmfuncs">
353 <title>Power Management</title>
354!Ekernel/power/pm.c
355 </chapter>
356
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357 <chapter id="devdrivers">
358 <title>Device drivers infrastructure</title>
359 <sect1><title>Device Drivers Base</title>
360<!--
361X!Iinclude/linux/device.h
362-->
363!Edrivers/base/driver.c
4dc3b16b 364!Edrivers/base/core.c
78b2290f 365!Edrivers/base/class.c
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366!Edrivers/base/firmware_class.c
367!Edrivers/base/transport_class.c
368!Edrivers/base/dmapool.c
369<!-- Cannot be included, because
370 attribute_container_add_class_device_adapter
371 and attribute_container_classdev_to_container
372 exceed allowed 44 characters maximum
373X!Edrivers/base/attribute_container.c
374-->
375!Edrivers/base/sys.c
376<!--
377X!Edrivers/base/interface.c
378-->
379!Edrivers/base/platform.c
380!Edrivers/base/bus.c
381 </sect1>
382 <sect1><title>Device Drivers Power Management</title>
383!Edrivers/base/power/main.c
384!Edrivers/base/power/resume.c
385!Edrivers/base/power/suspend.c
386 </sect1>
387 <sect1><title>Device Drivers ACPI Support</title>
388<!-- Internal functions only
389X!Edrivers/acpi/sleep/main.c
390X!Edrivers/acpi/sleep/wakeup.c
391X!Edrivers/acpi/motherboard.c
392X!Edrivers/acpi/bus.c
393-->
394!Edrivers/acpi/scan.c
d758a8fa 395!Idrivers/acpi/scan.c
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396<!-- No correct structured comments
397X!Edrivers/acpi/pci_bind.c
398-->
399 </sect1>
400 <sect1><title>Device drivers PnP support</title>
b8a36793 401!Idrivers/pnp/core.c
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402<!-- No correct structured comments
403X!Edrivers/pnp/system.c
404 -->
405!Edrivers/pnp/card.c
b8a36793 406!Idrivers/pnp/driver.c
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407!Edrivers/pnp/manager.c
408!Edrivers/pnp/support.c
409 </sect1>
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410 <sect1><title>Userspace IO devices</title>
411!Edrivers/uio/uio.c
412!Iinclude/linux/uio_driver.h
413 </sect1>
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414 </chapter>
415
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416 <chapter id="blkdev">
417 <title>Block Devices</title>
1d193f4f 418!Eblock/ll_rw_blk.c
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419 </chapter>
420
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421 <chapter id="chrdev">
422 <title>Char devices</title>
423!Efs/char_dev.c
424 </chapter>
425
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426 <chapter id="miscdev">
427 <title>Miscellaneous Devices</title>
428!Edrivers/char/misc.c
429 </chapter>
430
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431 <chapter id="parportdev">
432 <title>Parallel Port Devices</title>
433!Iinclude/linux/parport.h
434!Edrivers/parport/ieee1284.c
435!Edrivers/parport/share.c
436!Idrivers/parport/daisy.c
437 </chapter>
438
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439 <chapter id="message_devices">
440 <title>Message-based devices</title>
441 <sect1><title>Fusion message devices</title>
442!Edrivers/message/fusion/mptbase.c
443!Idrivers/message/fusion/mptbase.c
444!Edrivers/message/fusion/mptscsih.c
445!Idrivers/message/fusion/mptscsih.c
446!Idrivers/message/fusion/mptctl.c
447!Idrivers/message/fusion/mptspi.c
448!Idrivers/message/fusion/mptfc.c
449!Idrivers/message/fusion/mptlan.c
450 </sect1>
451 <sect1><title>I2O message devices</title>
452!Iinclude/linux/i2o.h
453!Idrivers/message/i2o/core.h
454!Edrivers/message/i2o/iop.c
455!Idrivers/message/i2o/iop.c
456!Idrivers/message/i2o/config-osm.c
457!Edrivers/message/i2o/exec-osm.c
458!Idrivers/message/i2o/exec-osm.c
459!Idrivers/message/i2o/bus-osm.c
460!Edrivers/message/i2o/device.c
461!Idrivers/message/i2o/device.c
462!Idrivers/message/i2o/driver.c
463!Idrivers/message/i2o/pci.c
464!Idrivers/message/i2o/i2o_block.c
465!Idrivers/message/i2o/i2o_scsi.c
466!Idrivers/message/i2o/i2o_proc.c
467 </sect1>
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468 </chapter>
469
470 <chapter id="snddev">
471 <title>Sound Devices</title>
4dc3b16b 472!Iinclude/sound/core.h
1da177e4 473!Esound/sound_core.c
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474!Iinclude/sound/pcm.h
475!Esound/core/pcm.c
476!Esound/core/device.c
477!Esound/core/info.c
478!Esound/core/rawmidi.c
479!Esound/core/sound.c
480!Esound/core/memory.c
481!Esound/core/pcm_memory.c
482!Esound/core/init.c
483!Esound/core/isadma.c
484!Esound/core/control.c
485!Esound/core/pcm_lib.c
486!Esound/core/hwdep.c
487!Esound/core/pcm_native.c
488!Esound/core/memalloc.c
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489<!-- FIXME: Removed for now since no structured comments in source
490X!Isound/sound_firmware.c
491-->
492 </chapter>
493
494 <chapter id="uart16x50">
495 <title>16x50 UART Driver</title>
4dc3b16b 496!Iinclude/linux/serial_core.h
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497!Edrivers/serial/serial_core.c
498!Edrivers/serial/8250.c
499 </chapter>
500
501 <chapter id="z85230">
502 <title>Z85230 Support Library</title>
503!Edrivers/net/wan/z85230.c
504 </chapter>
505
506 <chapter id="fbdev">
507 <title>Frame Buffer Library</title>
508
509 <para>
510 The frame buffer drivers depend heavily on four data structures.
511 These structures are declared in include/linux/fb.h. They are
512 fb_info, fb_var_screeninfo, fb_fix_screeninfo and fb_monospecs.
513 The last three can be made available to and from userland.
514 </para>
515
516 <para>
517 fb_info defines the current state of a particular video card.
518 Inside fb_info, there exists a fb_ops structure which is a
519 collection of needed functions to make fbdev and fbcon work.
520 fb_info is only visible to the kernel.
521 </para>
522
523 <para>
524 fb_var_screeninfo is used to describe the features of a video card
525 that are user defined. With fb_var_screeninfo, things such as
526 depth and the resolution may be defined.
527 </para>
528
529 <para>
530 The next structure is fb_fix_screeninfo. This defines the
531 properties of a card that are created when a mode is set and can't
532 be changed otherwise. A good example of this is the start of the
533 frame buffer memory. This "locks" the address of the frame buffer
534 memory, so that it cannot be changed or moved.
535 </para>
536
537 <para>
538 The last structure is fb_monospecs. In the old API, there was
539 little importance for fb_monospecs. This allowed for forbidden things
540 such as setting a mode of 800x600 on a fix frequency monitor. With
541 the new API, fb_monospecs prevents such things, and if used
542 correctly, can prevent a monitor from being cooked. fb_monospecs
543 will not be useful until kernels 2.5.x.
544 </para>
545
546 <sect1><title>Frame Buffer Memory</title>
547!Edrivers/video/fbmem.c
548 </sect1>
4dc3b16b 549<!--
1da177e4 550 <sect1><title>Frame Buffer Console</title>
4dc3b16b 551X!Edrivers/video/console/fbcon.c
1da177e4 552 </sect1>
4dc3b16b 553-->
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554 <sect1><title>Frame Buffer Colormap</title>
555!Edrivers/video/fbcmap.c
556 </sect1>
557<!-- FIXME:
558 drivers/video/fbgen.c has no docs, which stuffs up the sgml. Comment
559 out until somebody adds docs. KAO
560 <sect1><title>Frame Buffer Generic Functions</title>
561X!Idrivers/video/fbgen.c
562 </sect1>
563KAO -->
564 <sect1><title>Frame Buffer Video Mode Database</title>
565!Idrivers/video/modedb.c
566!Edrivers/video/modedb.c
567 </sect1>
568 <sect1><title>Frame Buffer Macintosh Video Mode Database</title>
8f2709b5 569!Edrivers/video/macmodes.c
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570 </sect1>
571 <sect1><title>Frame Buffer Fonts</title>
572 <para>
573 Refer to the file drivers/video/console/fonts.c for more information.
574 </para>
575<!-- FIXME: Removed for now since no structured comments in source
576X!Idrivers/video/console/fonts.c
577-->
578 </sect1>
579 </chapter>
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580
581 <chapter id="input_subsystem">
582 <title>Input Subsystem</title>
583!Iinclude/linux/input.h
584!Edrivers/input/input.c
585!Edrivers/input/ff-core.c
586!Edrivers/input/ff-memless.c
587 </chapter>
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588
589 <chapter id="spi">
590 <title>Serial Peripheral Interface (SPI)</title>
591 <para>
592 SPI is the "Serial Peripheral Interface", widely used with
593 embedded systems because it is a simple and efficient
594 interface: basically a multiplexed shift register.
595 Its three signal wires hold a clock (SCK, often in the range
596 of 1-20 MHz), a "Master Out, Slave In" (MOSI) data line, and
597 a "Master In, Slave Out" (MISO) data line.
598 SPI is a full duplex protocol; for each bit shifted out the
599 MOSI line (one per clock) another is shifted in on the MISO line.
600 Those bits are assembled into words of various sizes on the
601 way to and from system memory.
602 An additional chipselect line is usually active-low (nCS);
603 four signals are normally used for each peripheral, plus
604 sometimes an interrupt.
605 </para>
606 <para>
607 The SPI bus facilities listed here provide a generalized
608 interface to declare SPI busses and devices, manage them
609 according to the standard Linux driver model, and perform
610 input/output operations.
611 At this time, only "master" side interfaces are supported,
612 where Linux talks to SPI peripherals and does not implement
613 such a peripheral itself.
614 (Interfaces to support implementing SPI slaves would
615 necessarily look different.)
616 </para>
617 <para>
618 The programming interface is structured around two kinds of driver,
619 and two kinds of device.
620 A "Controller Driver" abstracts the controller hardware, which may
621 be as simple as a set of GPIO pins or as complex as a pair of FIFOs
622 connected to dual DMA engines on the other side of the SPI shift
623 register (maximizing throughput). Such drivers bridge between
624 whatever bus they sit on (often the platform bus) and SPI, and
625 expose the SPI side of their device as a
626 <structname>struct spi_master</structname>.
627 SPI devices are children of that master, represented as a
628 <structname>struct spi_device</structname> and manufactured from
629 <structname>struct spi_board_info</structname> descriptors which
630 are usually provided by board-specific initialization code.
631 A <structname>struct spi_driver</structname> is called a
632 "Protocol Driver", and is bound to a spi_device using normal
633 driver model calls.
634 </para>
635 <para>
636 The I/O model is a set of queued messages. Protocol drivers
637 submit one or more <structname>struct spi_message</structname>
638 objects, which are processed and completed asynchronously.
639 (There are synchronous wrappers, however.) Messages are
640 built from one or more <structname>struct spi_transfer</structname>
641 objects, each of which wraps a full duplex SPI transfer.
642 A variety of protocol tweaking options are needed, because
643 different chips adopt very different policies for how they
644 use the bits transferred with SPI.
645 </para>
646!Iinclude/linux/spi/spi.h
647!Fdrivers/spi/spi.c spi_register_board_info
648!Edrivers/spi/spi.c
649 </chapter>
650
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651 <chapter id="i2c">
652 <title>I<superscript>2</superscript>C and SMBus Subsystem</title>
653
654 <para>
655 I<superscript>2</superscript>C (or without fancy typography, "I2C")
656 is an acronym for the "Inter-IC" bus, a simple bus protocol which is
657 widely used where low data rate communications suffice.
658 Since it's also a licensed trademark, some vendors use another
659 name (such as "Two-Wire Interface", TWI) for the same bus.
660 I2C only needs two signals (SCL for clock, SDA for data), conserving
661 board real estate and minimizing signal quality issues.
662 Most I2C devices use seven bit addresses, and bus speeds of up
663 to 400 kHz; there's a high speed extension (3.4 MHz) that's not yet
664 found wide use.
665 I2C is a multi-master bus; open drain signaling is used to
666 arbitrate between masters, as well as to handshake and to
667 synchronize clocks from slower clients.
668 </para>
669
670 <para>
671 The Linux I2C programming interfaces support only the master
672 side of bus interactions, not the slave side.
673 The programming interface is structured around two kinds of driver,
674 and two kinds of device.
675 An I2C "Adapter Driver" abstracts the controller hardware; it binds
676 to a physical device (perhaps a PCI device or platform_device) and
677 exposes a <structname>struct i2c_adapter</structname> representing
678 each I2C bus segment it manages.
679 On each I2C bus segment will be I2C devices represented by a
680 <structname>struct i2c_client</structname>. Those devices will
681 be bound to a <structname>struct i2c_driver</structname>,
682 which should follow the standard Linux driver model.
683 (At this writing, a legacy model is more widely used.)
684 There are functions to perform various I2C protocol operations; at
685 this writing all such functions are usable only from task context.
686 </para>
687
688 <para>
689 The System Management Bus (SMBus) is a sibling protocol. Most SMBus
690 systems are also I2C conformant. The electrical constraints are
691 tighter for SMBus, and it standardizes particular protocol messages
692 and idioms. Controllers that support I2C can also support most
693 SMBus operations, but SMBus controllers don't support all the protocol
694 options that an I2C controller will.
695 There are functions to perform various SMBus protocol operations,
696 either using I2C primitives or by issuing SMBus commands to
697 i2c_adapter devices which don't support those I2C operations.
698 </para>
699
700!Iinclude/linux/i2c.h
701!Fdrivers/i2c/i2c-boardinfo.c i2c_register_board_info
702!Edrivers/i2c/i2c-core.c
703 </chapter>
704
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705 <chapter id="splice">
706 <title>splice API</title>
79685b8d 707 <para>
932cc6d4 708 splice is a method for moving blocks of data around inside the
79685b8d 709 kernel, without continually transferring them between the kernel
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710 and user space.
711 </para>
712!Iinclude/linux/splice.h
713!Ffs/splice.c
714 </chapter>
715
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716 <chapter id="pipes">
717 <title>pipes API</title>
718 <para>
719 Pipe interfaces are all for in-kernel (builtin image) use.
720 They are not exported for use by modules.
721 </para>
722!Iinclude/linux/pipe_fs_i.h
723!Ffs/pipe.c
724 </chapter>
d64f73be 725
1da177e4 726</book>