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-rw-r--r--Documentation/DocBook/Makefile2
-rw-r--r--Documentation/DocBook/device-drivers.tmpl418
-rw-r--r--Documentation/DocBook/kernel-api.tmpl377
-rw-r--r--Documentation/cgroups/cpusets.txt65
-rw-r--r--Documentation/driver-model/device.txt8
-rw-r--r--Documentation/filesystems/sysfs.txt50
-rw-r--r--Documentation/kernel-parameters.txt6
7 files changed, 492 insertions, 434 deletions
diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile
index dc3154e49279..1462ed86d40a 100644
--- a/Documentation/DocBook/Makefile
+++ b/Documentation/DocBook/Makefile
@@ -6,7 +6,7 @@
# To add a new book the only step required is to add the book to the
# list of DOCBOOKS.
-DOCBOOKS := z8530book.xml mcabook.xml \
+DOCBOOKS := z8530book.xml mcabook.xml device-drivers.xml \
kernel-hacking.xml kernel-locking.xml deviceiobook.xml \
procfs-guide.xml writing_usb_driver.xml networking.xml \
kernel-api.xml filesystems.xml lsm.xml usb.xml kgdb.xml \
diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl
new file mode 100644
index 000000000000..94a20fe8fedf
--- /dev/null
+++ b/Documentation/DocBook/device-drivers.tmpl
@@ -0,0 +1,418 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
+ "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
+
+<book id="LinuxDriversAPI">
+ <bookinfo>
+ <title>Linux Device Drivers</title>
+
+ <legalnotice>
+ <para>
+ This documentation is free software; you can redistribute
+ it and/or modify it under the terms of the GNU General Public
+ License as published by the Free Software Foundation; either
+ version 2 of the License, or (at your option) any later
+ version.
+ </para>
+
+ <para>
+ This program is distributed in the hope that it will be
+ useful, but WITHOUT ANY WARRANTY; without even the implied
+ warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ See the GNU General Public License for more details.
+ </para>
+
+ <para>
+ You should have received a copy of the GNU General Public
+ License along with this program; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ MA 02111-1307 USA
+ </para>
+
+ <para>
+ For more details see the file COPYING in the source
+ distribution of Linux.
+ </para>
+ </legalnotice>
+ </bookinfo>
+
+<toc></toc>
+
+ <chapter id="Basics">
+ <title>Driver Basics</title>
+ <sect1><title>Driver Entry and Exit points</title>
+!Iinclude/linux/init.h
+ </sect1>
+
+ <sect1><title>Atomic and pointer manipulation</title>
+!Iarch/x86/include/asm/atomic_32.h
+!Iarch/x86/include/asm/unaligned.h
+ </sect1>
+
+ <sect1><title>Delaying, scheduling, and timer routines</title>
+!Iinclude/linux/sched.h
+!Ekernel/sched.c
+!Ekernel/timer.c
+ </sect1>
+ <sect1><title>High-resolution timers</title>
+!Iinclude/linux/ktime.h
+!Iinclude/linux/hrtimer.h
+!Ekernel/hrtimer.c
+ </sect1>
+ <sect1><title>Workqueues and Kevents</title>
+!Ekernel/workqueue.c
+ </sect1>
+ <sect1><title>Internal Functions</title>
+!Ikernel/exit.c
+!Ikernel/signal.c
+!Iinclude/linux/kthread.h
+!Ekernel/kthread.c
+ </sect1>
+
+ <sect1><title>Kernel objects manipulation</title>
+<!--
+X!Iinclude/linux/kobject.h
+-->
+!Elib/kobject.c
+ </sect1>
+
+ <sect1><title>Kernel utility functions</title>
+!Iinclude/linux/kernel.h
+!Ekernel/printk.c
+!Ekernel/panic.c
+!Ekernel/sys.c
+!Ekernel/rcupdate.c
+ </sect1>
+
+ <sect1><title>Device Resource Management</title>
+!Edrivers/base/devres.c
+ </sect1>
+
+ </chapter>
+
+ <chapter id="devdrivers">
+ <title>Device drivers infrastructure</title>
+ <sect1><title>Device Drivers Base</title>
+<!--
+X!Iinclude/linux/device.h
+-->
+!Edrivers/base/driver.c
+!Edrivers/base/core.c
+!Edrivers/base/class.c
+!Edrivers/base/firmware_class.c
+!Edrivers/base/transport_class.c
+<!-- Cannot be included, because
+ attribute_container_add_class_device_adapter
+ and attribute_container_classdev_to_container
+ exceed allowed 44 characters maximum
+X!Edrivers/base/attribute_container.c
+-->
+!Edrivers/base/sys.c
+<!--
+X!Edrivers/base/interface.c
+-->
+!Edrivers/base/platform.c
+!Edrivers/base/bus.c
+ </sect1>
+ <sect1><title>Device Drivers Power Management</title>
+!Edrivers/base/power/main.c
+ </sect1>
+ <sect1><title>Device Drivers ACPI Support</title>
+<!-- Internal functions only
+X!Edrivers/acpi/sleep/main.c
+X!Edrivers/acpi/sleep/wakeup.c
+X!Edrivers/acpi/motherboard.c
+X!Edrivers/acpi/bus.c
+-->
+!Edrivers/acpi/scan.c
+!Idrivers/acpi/scan.c
+<!-- No correct structured comments
+X!Edrivers/acpi/pci_bind.c
+-->
+ </sect1>
+ <sect1><title>Device drivers PnP support</title>
+!Idrivers/pnp/core.c
+<!-- No correct structured comments
+X!Edrivers/pnp/system.c
+ -->
+!Edrivers/pnp/card.c
+!Idrivers/pnp/driver.c
+!Edrivers/pnp/manager.c
+!Edrivers/pnp/support.c
+ </sect1>
+ <sect1><title>Userspace IO devices</title>
+!Edrivers/uio/uio.c
+!Iinclude/linux/uio_driver.h
+ </sect1>
+ </chapter>
+
+ <chapter id="parportdev">
+ <title>Parallel Port Devices</title>
+!Iinclude/linux/parport.h
+!Edrivers/parport/ieee1284.c
+!Edrivers/parport/share.c
+!Idrivers/parport/daisy.c
+ </chapter>
+
+ <chapter id="message_devices">
+ <title>Message-based devices</title>
+ <sect1><title>Fusion message devices</title>
+!Edrivers/message/fusion/mptbase.c
+!Idrivers/message/fusion/mptbase.c
+!Edrivers/message/fusion/mptscsih.c
+!Idrivers/message/fusion/mptscsih.c
+!Idrivers/message/fusion/mptctl.c
+!Idrivers/message/fusion/mptspi.c
+!Idrivers/message/fusion/mptfc.c
+!Idrivers/message/fusion/mptlan.c
+ </sect1>
+ <sect1><title>I2O message devices</title>
+!Iinclude/linux/i2o.h
+!Idrivers/message/i2o/core.h
+!Edrivers/message/i2o/iop.c
+!Idrivers/message/i2o/iop.c
+!Idrivers/message/i2o/config-osm.c
+!Edrivers/message/i2o/exec-osm.c
+!Idrivers/message/i2o/exec-osm.c
+!Idrivers/message/i2o/bus-osm.c
+!Edrivers/message/i2o/device.c
+!Idrivers/message/i2o/device.c
+!Idrivers/message/i2o/driver.c
+!Idrivers/message/i2o/pci.c
+!Idrivers/message/i2o/i2o_block.c
+!Idrivers/message/i2o/i2o_scsi.c
+!Idrivers/message/i2o/i2o_proc.c
+ </sect1>
+ </chapter>
+
+ <chapter id="snddev">
+ <title>Sound Devices</title>
+!Iinclude/sound/core.h
+!Esound/sound_core.c
+!Iinclude/sound/pcm.h
+!Esound/core/pcm.c
+!Esound/core/device.c
+!Esound/core/info.c
+!Esound/core/rawmidi.c
+!Esound/core/sound.c
+!Esound/core/memory.c
+!Esound/core/pcm_memory.c
+!Esound/core/init.c
+!Esound/core/isadma.c
+!Esound/core/control.c
+!Esound/core/pcm_lib.c
+!Esound/core/hwdep.c
+!Esound/core/pcm_native.c
+!Esound/core/memalloc.c
+<!-- FIXME: Removed for now since no structured comments in source
+X!Isound/sound_firmware.c
+-->
+ </chapter>
+
+ <chapter id="uart16x50">
+ <title>16x50 UART Driver</title>
+!Iinclude/linux/serial_core.h
+!Edrivers/serial/serial_core.c
+!Edrivers/serial/8250.c
+ </chapter>
+
+ <chapter id="fbdev">
+ <title>Frame Buffer Library</title>
+
+ <para>
+ The frame buffer drivers depend heavily on four data structures.
+ These structures are declared in include/linux/fb.h. They are
+ fb_info, fb_var_screeninfo, fb_fix_screeninfo and fb_monospecs.
+ The last three can be made available to and from userland.
+ </para>
+
+ <para>
+ fb_info defines the current state of a particular video card.
+ Inside fb_info, there exists a fb_ops structure which is a
+ collection of needed functions to make fbdev and fbcon work.
+ fb_info is only visible to the kernel.
+ </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>
+
+ <chapter id="i2c">
+ <title>I<superscript>2</superscript>C and SMBus Subsystem</title>
+
+ <para>
+ I<superscript>2</superscript>C (or without fancy typography, "I2C")
+ is an acronym for the "Inter-IC" bus, a simple bus protocol which is
+ widely used where low data rate communications suffice.
+ Since it's also a licensed trademark, some vendors use another
+ name (such as "Two-Wire Interface", TWI) for the same bus.
+ I2C only needs two signals (SCL for clock, SDA for data), conserving
+ board real estate and minimizing signal quality issues.
+ Most I2C devices use seven bit addresses, and bus speeds of up
+ to 400 kHz; there's a high speed extension (3.4 MHz) that's not yet
+ found wide use.
+ I2C is a multi-master bus; open drain signaling is used to
+ arbitrate between masters, as well as to handshake and to
+ synchronize clocks from slower clients.
+ </para>
+
+ <para>
+ The Linux I2C programming interfaces support only the master
+ side of bus interactions, not the slave side.
+ The programming interface is structured around two kinds of driver,
+ and two kinds of device.
+ An I2C "Adapter Driver" abstracts the controller hardware; it binds
+ to a physical device (perhaps a PCI device or platform_device) and
+ exposes a <structname>struct i2c_adapter</structname> representing
+ each I2C bus segment it manages.
+ On each I2C bus segment will be I2C devices represented by a
+ <structname>struct i2c_client</structname>. Those devices will
+ be bound to a <structname>struct i2c_driver</structname>,
+ which should follow the standard Linux driver model.
+ (At this writing, a legacy model is more widely used.)
+ There are functions to perform various I2C protocol operations; at
+ this writing all such functions are usable only from task context.
+ </para>
+
+ <para>
+ The System Management Bus (SMBus) is a sibling protocol. Most SMBus
+ systems are also I2C conformant. The electrical constraints are
+ tighter for SMBus, and it standardizes particular protocol messages
+ and idioms. Controllers that support I2C can also support most
+ SMBus operations, but SMBus controllers don't support all the protocol
+ options that an I2C controller will.
+ There are functions to perform various SMBus protocol operations,
+ either using I2C primitives or by issuing SMBus commands to
+ i2c_adapter devices which don't support those I2C operations.
+ </para>
+
+!Iinclude/linux/i2c.h
+!Fdrivers/i2c/i2c-boardinfo.c i2c_register_board_info
+!Edrivers/i2c/i2c-core.c
+ </chapter>
+
+</book>
diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl
index 5818ff75786a..bc962cda6504 100644
--- a/Documentation/DocBook/kernel-api.tmpl
+++ b/Documentation/DocBook/kernel-api.tmpl
@@ -38,58 +38,6 @@
<toc></toc>
- <chapter id="Basics">
- <title>Driver Basics</title>
- <sect1><title>Driver Entry and Exit points</title>
-!Iinclude/linux/init.h
- </sect1>
-
- <sect1><title>Atomic and pointer manipulation</title>
-!Iarch/x86/include/asm/atomic_32.h
-!Iarch/x86/include/asm/unaligned.h
- </sect1>
-
- <sect1><title>Delaying, scheduling, and timer routines</title>
-!Iinclude/linux/sched.h
-!Ekernel/sched.c
-!Ekernel/timer.c
- </sect1>
- <sect1><title>High-resolution timers</title>
-!Iinclude/linux/ktime.h
-!Iinclude/linux/hrtimer.h
-!Ekernel/hrtimer.c
- </sect1>
- <sect1><title>Workqueues and Kevents</title>
-!Ekernel/workqueue.c
- </sect1>
- <sect1><title>Internal Functions</title>
-!Ikernel/exit.c
-!Ikernel/signal.c
-!Iinclude/linux/kthread.h
-!Ekernel/kthread.c
- </sect1>
-
- <sect1><title>Kernel objects manipulation</title>
-<!--
-X!Iinclude/linux/kobject.h
--->
-!Elib/kobject.c
- </sect1>
-
- <sect1><title>Kernel utility functions</title>
-!Iinclude/linux/kernel.h
-!Ekernel/printk.c
-!Ekernel/panic.c
-!Ekernel/sys.c
-!Ekernel/rcupdate.c
- </sect1>
-
- <sect1><title>Device Resource Management</title>
-!Edrivers/base/devres.c
- </sect1>
-
- </chapter>
-
<chapter id="adt">
<title>Data Types</title>
<sect1><title>Doubly Linked Lists</title>
@@ -298,62 +246,6 @@ X!Earch/x86/kernel/mca_32.c
!Ikernel/acct.c
</chapter>
- <chapter id="devdrivers">
- <title>Device drivers infrastructure</title>
- <sect1><title>Device Drivers Base</title>
-<!--
-X!Iinclude/linux/device.h
--->
-!Edrivers/base/driver.c
-!Edrivers/base/core.c
-!Edrivers/base/class.c
-!Edrivers/base/firmware_class.c
-!Edrivers/base/transport_class.c
-<!-- Cannot be included, because
- attribute_container_add_class_device_adapter
- and attribute_container_classdev_to_container
- exceed allowed 44 characters maximum
-X!Edrivers/base/attribute_container.c
--->
-!Edrivers/base/sys.c
-<!--
-X!Edrivers/base/interface.c
--->
-!Edrivers/base/platform.c
-!Edrivers/base/bus.c
- </sect1>
- <sect1><title>Device Drivers Power Management</title>
-!Edrivers/base/power/main.c
- </sect1>
- <sect1><title>Device Drivers ACPI Support</title>
-<!-- Internal functions only
-X!Edrivers/acpi/sleep/main.c
-X!Edrivers/acpi/sleep/wakeup.c
-X!Edrivers/acpi/motherboard.c
-X!Edrivers/acpi/bus.c
--->
-!Edrivers/acpi/scan.c
-!Idrivers/acpi/scan.c
-<!-- No correct structured comments
-X!Edrivers/acpi/pci_bind.c
--->
- </sect1>
- <sect1><title>Device drivers PnP support</title>
-!Idrivers/pnp/core.c
-<!-- No correct structured comments
-X!Edrivers/pnp/system.c
- -->
-!Edrivers/pnp/card.c
-!Idrivers/pnp/driver.c
-!Edrivers/pnp/manager.c
-!Edrivers/pnp/support.c
- </sect1>
- <sect1><title>Userspace IO devices</title>
-!Edrivers/uio/uio.c
-!Iinclude/linux/uio_driver.h
- </sect1>
- </chapter>
-
<chapter id="blkdev">
<title>Block Devices</title>
!Eblock/blk-core.c
@@ -381,275 +273,6 @@ X!Edrivers/pnp/system.c
!Edrivers/char/misc.c
</chapter>
- <chapter id="parportdev">
- <title>Parallel Port Devices</title>
-!Iinclude/linux/parport.h
-!Edrivers/parport/ieee1284.c
-!Edrivers/parport/share.c
-!Idrivers/parport/daisy.c
- </chapter>
-
- <chapter id="message_devices">
- <title>Message-based devices</title>
- <sect1><title>Fusion message devices</title>
-!Edrivers/message/fusion/mptbase.c
-!Idrivers/message/fusion/mptbase.c
-!Edrivers/message/fusion/mptscsih.c
-!Idrivers/message/fusion/mptscsih.c
-!Idrivers/message/fusion/mptctl.c
-!Idrivers/message/fusion/mptspi.c
-!Idrivers/message/fusion/mptfc.c
-!Idrivers/message/fusion/mptlan.c
- </sect1>
- <sect1><title>I2O message devices</title>
-!Iinclude/linux/i2o.h
-!Idrivers/message/i2o/core.h
-!Edrivers/message/i2o/iop.c
-!Idrivers/message/i2o/iop.c
-!Idrivers/message/i2o/config-osm.c
-!Edrivers/message/i2o/exec-osm.c
-!Idrivers/message/i2o/exec-osm.c
-!Idrivers/message/i2o/bus-osm.c
-!Edrivers/message/i2o/device.c
-!Idrivers/message/i2o/device.c
-!Idrivers/message/i2o/driver.c
-!Idrivers/message/i2o/pci.c
-!Idrivers/message/i2o/i2o_block.c
-!Idrivers/message/i2o/i2o_scsi.c
-!Idrivers/message/i2o/i2o_proc.c
- </sect1>
- </chapter>
-
- <chapter id="snddev">
- <title>Sound Devices</title>
-!Iinclude/sound/core.h
-!Esound/sound_core.c
-!Iinclude/sound/pcm.h
-!Esound/core/pcm.c
-!Esound/core/device.c
-!Esound/core/info.c
-!Esound/core/rawmidi.c
-!Esound/core/sound.c
-!Esound/core/memory.c
-!Esound/core/pcm_memory.c
-!Esound/core/init.c
-!Esound/core/isadma.c
-!Esound/core/control.c
-!Esound/core/pcm_lib.c
-!Esound/core/hwdep.c
-!Esound/core/pcm_native.c
-!Esound/core/memalloc.c
-<!-- FIXME: Removed for now since no structured comments in source
-X!Isound/sound_firmware.c
--->
- </chapter>
-
- <chapter id="uart16x50">
- <title>16x50 UART Driver</title>
-!Iinclude/linux/serial_core.h
-!Edrivers/serial/serial_core.c
-!Edrivers/serial/8250.c
- </chapter>
-
- <chapter id="fbdev">
- <title>Frame Buffer Library</title>
-
- <para>
- The frame buffer drivers depend heavily on four data structures.
- These structures are declared in include/linux/fb.h. They are
- fb_info, fb_var_screeninfo, fb_fix_screeninfo and fb_monospecs.
- The last three can be made available to and from userland.
- </para>
-
- <para>
- fb_info defines the current state of a particular video card.
- Inside fb_info, there exists a fb_ops structure which is a
- collection of needed functions to make fbdev and fbcon work.
- fb_info is only visible to the kernel.
- </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>
-
- <chapter id="i2c">
- <title>I<superscript>2</superscript>C and SMBus Subsystem</title>
-
- <para>
- I<superscript>2</superscript>C (or without fancy typography, "I2C")
- is an acronym for the "Inter-IC" bus, a simple bus protocol which is
- widely used where low data rate communications suffice.
- Since it's also a licensed trademark, some vendors use another
- name (such as "Two-Wire Interface", TWI) for the same bus.
- I2C only needs two signals (SCL for clock, SDA for data), conserving
- board real estate and minimizing signal quality issues.
- Most I2C devices use seven bit addresses, and bus speeds of up
- to 400 kHz; there's a high speed extension (3.4 MHz) that's not yet
- found wide use.
- I2C is a multi-master bus; open drain signaling is used to
- arbitrate between masters, as well as to handshake and to
- synchronize clocks from slower clients.
- </para>
-
- <para>
- The Linux I2C programming interfaces support only the master
- side of bus interactions, not the slave side.
- The programming interface is structured around two kinds of driver,
- and two kinds of device.
- An I2C "Adapter Driver" abstracts the controller hardware; it binds
- to a physical device (perhaps a PCI device or platform_device) and
- exposes a <structname>struct i2c_adapter</structname> representing
- each I2C bus segment it manages.
- On each I2C bus segment will be I2C devices represented by a
- <structname>struct i2c_client</structname>. Those devices will
- be bound to a <structname>struct i2c_driver</structname>,
- which should follow the standard Linux driver model.
- (At this writing, a legacy model is more widely used.)
- There are functions to perform various I2C protocol operations; at
- this writing all such functions are usable only from task context.
- </para>
-
- <para>
- The System Management Bus (SMBus) is a sibling protocol. Most SMBus
- systems are also I2C conformant. The electrical constraints are
- tighter for SMBus, and it standardizes particular protocol messages
- and idioms. Controllers that support I2C can also support most
- SMBus operations, but SMBus controllers don't support all the protocol
- options that an I2C controller will.
- There are functions to perform various SMBus protocol operations,
- either using I2C primitives or by issuing SMBus commands to
- i2c_adapter devices which don't support those I2C operations.
- </para>
-
-!Iinclude/linux/i2c.h
-!Fdrivers/i2c/i2c-boardinfo.c i2c_register_board_info
-!Edrivers/i2c/i2c-core.c
- </chapter>
-
<chapter id="clk">
<title>Clock Framework</title>
diff --git a/Documentation/cgroups/cpusets.txt b/Documentation/cgroups/cpusets.txt
index 5c86c258c791..0611e9528c7c 100644
--- a/Documentation/cgroups/cpusets.txt
+++ b/Documentation/cgroups/cpusets.txt
@@ -142,7 +142,7 @@ into the rest of the kernel, none in performance critical paths:
- in fork and exit, to attach and detach a task from its cpuset.
- in sched_setaffinity, to mask the requested CPUs by what's
allowed in that tasks cpuset.
- - in sched.c migrate_all_tasks(), to keep migrating tasks within
+ - in sched.c migrate_live_tasks(), to keep migrating tasks within
the CPUs allowed by their cpuset, if possible.
- in the mbind and set_mempolicy system calls, to mask the requested
Memory Nodes by what's allowed in that tasks cpuset.
@@ -175,6 +175,10 @@ files describing that cpuset:
- mem_exclusive flag: is memory placement exclusive?
- mem_hardwall flag: is memory allocation hardwalled
- memory_pressure: measure of how much paging pressure in cpuset
+ - memory_spread_page flag: if set, spread page cache evenly on allowed nodes
+ - memory_spread_slab flag: if set, spread slab cache evenly on allowed nodes
+ - sched_load_balance flag: if set, load balance within CPUs on that cpuset
+ - sched_relax_domain_level: the searching range when migrating tasks
In addition, the root cpuset only has the following file:
- memory_pressure_enabled flag: compute memory_pressure?
@@ -252,7 +256,7 @@ is causing.
This is useful both on tightly managed systems running a wide mix of
submitted jobs, which may choose to terminate or re-prioritize jobs that
-are trying to use more memory than allowed on the nodes assigned them,
+are trying to use more memory than allowed on the nodes assigned to them,
and with tightly coupled, long running, massively parallel scientific
computing jobs that will dramatically fail to meet required performance
goals if they start to use more memory than allowed to them.
@@ -378,7 +382,7 @@ as cpusets and sched_setaffinity.
The algorithmic cost of load balancing and its impact on key shared
kernel data structures such as the task list increases more than
linearly with the number of CPUs being balanced. So the scheduler
-has support to partition the systems CPUs into a number of sched
+has support to partition the systems CPUs into a number of sched
domains such that it only load balances within each sched domain.
Each sched domain covers some subset of the CPUs in the system;
no two sched domains overlap; some CPUs might not be in any sched
@@ -485,17 +489,22 @@ of CPUs allowed to a cpuset having 'sched_load_balance' enabled.
The internal kernel cpuset to scheduler interface passes from the
cpuset code to the scheduler code a partition of the load balanced
CPUs in the system. This partition is a set of subsets (represented
-as an array of cpumask_t) of CPUs, pairwise disjoint, that cover all
-the CPUs that must be load balanced.
-
-Whenever the 'sched_load_balance' flag changes, or CPUs come or go
-from a cpuset with this flag enabled, or a cpuset with this flag
-enabled is removed, the cpuset code builds a new such partition and
-passes it to the scheduler sched domain setup code, to have the sched
-domains rebuilt as necessary.
+as an array of struct cpumask) of CPUs, pairwise disjoint, that cover
+all the CPUs that must be load balanced.
+
+The cpuset code builds a new such partition and passes it to the
+scheduler sched domain setup code, to have the sched domains rebuilt
+as necessary, whenever:
+ - the 'sched_load_balance' flag of a cpuset with non-empty CPUs changes,
+ - or CPUs come or go from a cpuset with this flag enabled,
+ - or 'sched_relax_domain_level' value of a cpuset with non-empty CPUs
+ and with this flag enabled changes,
+ - or a cpuset with non-empty CPUs and with this flag enabled is removed,
+ - or a cpu is offlined/onlined.
This partition exactly defines what sched domains the scheduler should
-setup - one sched domain for each element (cpumask_t) in the partition.
+setup - one sched domain for each element (struct cpumask) in the
+partition.
The scheduler remembers the currently active sched domain partitions.
When the scheduler routine partition_sched_domains() is invoked from
@@ -559,7 +568,7 @@ domain, the largest value among those is used. Be careful, if one
requests 0 and others are -1 then 0 is used.
Note that modifying this file will have both good and bad effects,
-and whether it is acceptable or not will be depend on your situation.
+and whether it is acceptable or not depends on your situation.
Don't modify this file if you are not sure.
If your situation is:
@@ -600,19 +609,15 @@ to allocate a page of memory for that task.
If a cpuset has its 'cpus' modified, then each task in that cpuset
will have its allowed CPU placement changed immediately. Similarly,
-if a tasks pid is written to a cpusets 'tasks' file, in either its
-current cpuset or another cpuset, then its allowed CPU placement is
-changed immediately. If such a task had been bound to some subset
-of its cpuset using the sched_setaffinity() call, the task will be
-allowed to run on any CPU allowed in its new cpuset, negating the
-affect of the prior sched_setaffinity() call.
+if a tasks pid is written to another cpusets 'tasks' file, then its
+allowed CPU placement is changed immediately. If such a task had been
+bound to some subset of its cpuset using the sched_setaffinity() call,
+the task will be allowed to run on any CPU allowed in its new cpuset,
+negating the effect of the prior sched_setaffinity() call.
In summary, the memory placement of a task whose cpuset is changed is
updated by the kernel, on the next allocation of a page for that task,
-but the processor placement is not updated, until that tasks pid is
-rewritten to the 'tasks' file of its cpuset. This is done to avoid
-impacting the scheduler code in the kernel with a check for changes
-in a tasks processor placement.
+and the processor placement is updated immediately.
Normally, once a page is allocated (given a physical page
of main memory) then that page stays on whatever node it
@@ -681,10 +686,14 @@ and then start a subshell 'sh' in that cpuset:
# The next line should display '/Charlie'
cat /proc/self/cpuset
-In the future, a C library interface to cpusets will likely be
-available. For now, the only way to query or modify cpusets is
-via the cpuset file system, using the various cd, mkdir, echo, cat,
-rmdir commands from the shell, or their equivalent from C.
+There are ways to query or modify cpusets:
+ - via the cpuset file system directly, using the various cd, mkdir, echo,
+ cat, rmdir commands from the shell, or their equivalent from C.
+ - via the C library libcpuset.
+ - via the C library libcgroup.
+ (http://sourceforge.net/proects/libcg/)
+ - via the python application cset.
+ (http://developer.novell.com/wiki/index.php/Cpuset)
The sched_setaffinity calls can also be done at the shell prompt using
SGI's runon or Robert Love's taskset. The mbind and set_mempolicy
@@ -756,7 +765,7 @@ mount -t cpuset X /dev/cpuset
is equivalent to
-mount -t cgroup -ocpuset X /dev/cpuset
+mount -t cgroup -ocpuset,noprefix X /dev/cpuset
echo "/sbin/cpuset_release_agent" > /dev/cpuset/release_agent
2.2 Adding/removing cpus
diff --git a/Documentation/driver-model/device.txt b/Documentation/driver-model/device.txt
index a05ec50f8004..a7cbfff40d07 100644
--- a/Documentation/driver-model/device.txt
+++ b/Documentation/driver-model/device.txt
@@ -127,9 +127,11 @@ void unlock_device(struct device * dev);
Attributes
~~~~~~~~~~
struct device_attribute {
- struct attribute attr;
- ssize_t (*show)(struct device * dev, char * buf, size_t count, loff_t off);
- ssize_t (*store)(struct device * dev, const char * buf, size_t count, loff_t off);
+ struct attribute attr;
+ ssize_t (*show)(struct device *dev, struct device_attribute *attr,
+ char *buf);
+ ssize_t (*store)(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count);
};
Attributes of devices can be exported via drivers using a simple
diff --git a/Documentation/filesystems/sysfs.txt b/Documentation/filesystems/sysfs.txt
index 9e9c348275a9..7e81e37c0b1e 100644
--- a/Documentation/filesystems/sysfs.txt
+++ b/Documentation/filesystems/sysfs.txt
@@ -2,8 +2,10 @@
sysfs - _The_ filesystem for exporting kernel objects.
Patrick Mochel <mochel@osdl.org>
+Mike Murphy <mamurph@cs.clemson.edu>
-10 January 2003
+Revised: 22 February 2009
+Original: 10 January 2003
What it is:
@@ -64,12 +66,13 @@ An attribute definition is simply:
struct attribute {
char * name;
+ struct module *owner;
mode_t mode;
};
-int sysfs_create_file(struct kobject * kobj, struct attribute * attr);
-void sysfs_remove_file(struct kobject * kobj, struct attribute * attr);
+int sysfs_create_file(struct kobject * kobj, const struct attribute * attr);
+void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr);
A bare attribute contains no means to read or write the value of the
@@ -80,9 +83,11 @@ a specific object type.
For example, the driver model defines struct device_attribute like:
struct device_attribute {
- struct attribute attr;
- ssize_t (*show)(struct device * dev, char * buf);
- ssize_t (*store)(struct device * dev, const char * buf);
+ struct attribute attr;
+ ssize_t (*show)(struct device *dev, struct device_attribute *attr,
+ char *buf);
+ ssize_t (*store)(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count);
};
int device_create_file(struct device *, struct device_attribute *);
@@ -90,12 +95,8 @@ void device_remove_file(struct device *, struct device_attribute *);
It also defines this helper for defining device attributes:
-#define DEVICE_ATTR(_name, _mode, _show, _store) \
-struct device_attribute dev_attr_##_name = { \
- .attr = {.name = __stringify(_name) , .mode = _mode }, \
- .show = _show, \
- .store = _store, \
-};
+#define DEVICE_ATTR(_name, _mode, _show, _store) \
+struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
For example, declaring
@@ -107,9 +108,9 @@ static struct device_attribute dev_attr_foo = {
.attr = {
.name = "foo",
.mode = S_IWUSR | S_IRUGO,
+ .show = show_foo,
+ .store = store_foo,
},
- .show = show_foo,
- .store = store_foo,
};
@@ -161,10 +162,12 @@ To read or write attributes, show() or store() methods must be
specified when declaring the attribute. The method types should be as
simple as those defined for device attributes:
- ssize_t (*show)(struct device * dev, char * buf);
- ssize_t (*store)(struct device * dev, const char * buf);
+ssize_t (*show)(struct device * dev, struct device_attribute * attr,
+ char * buf);
+ssize_t (*store)(struct device * dev, struct device_attribute * attr,
+ const char * buf);
-IOW, they should take only an object and a buffer as parameters.
+IOW, they should take only an object, an attribute, and a buffer as parameters.
sysfs allocates a buffer of size (PAGE_SIZE) and passes it to the
@@ -299,14 +302,16 @@ The following interface layers currently exist in sysfs:
Structure:
struct device_attribute {
- struct attribute attr;
- ssize_t (*show)(struct device * dev, char * buf);
- ssize_t (*store)(struct device * dev, const char * buf);
+ struct attribute attr;
+ ssize_t (*show)(struct device *dev, struct device_attribute *attr,
+ char *buf);
+ ssize_t (*store)(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count);
};
Declaring:
-DEVICE_ATTR(_name, _str, _mode, _show, _store);
+DEVICE_ATTR(_name, _mode, _show, _store);
Creation/Removal:
@@ -342,7 +347,8 @@ Structure:
struct driver_attribute {
struct attribute attr;
ssize_t (*show)(struct device_driver *, char * buf);
- ssize_t (*store)(struct device_driver *, const char * buf);
+ ssize_t (*store)(struct device_driver *, const char * buf,
+ size_t count);
};
Declaring:
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index b182626739ea..f6d5d5b9b2b1 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -114,7 +114,7 @@ In addition, the following text indicates that the option:
Parameters denoted with BOOT are actually interpreted by the boot
loader, and have no meaning to the kernel directly.
Do not modify the syntax of boot loader parameters without extreme
-need or coordination with <Documentation/x86/i386/boot.txt>.
+need or coordination with <Documentation/x86/boot.txt>.
There are also arch-specific kernel-parameters not documented here.
See for example <Documentation/x86/x86_64/boot-options.txt>.
@@ -134,7 +134,7 @@ and is between 256 and 4096 characters. It is defined in the file
acpi= [HW,ACPI,X86-64,i386]
Advanced Configuration and Power Interface
- Format: { force | off | ht | strict | noirq }
+ Format: { force | off | ht | strict | noirq | rsdt }
force -- enable ACPI if default was off
off -- disable ACPI if default was on
noirq -- do not use ACPI for IRQ routing
@@ -2449,7 +2449,7 @@ and is between 256 and 4096 characters. It is defined in the file
See Documentation/fb/modedb.txt.
vga= [BOOT,X86-32] Select a particular video mode
- See Documentation/x86/i386/boot.txt and
+ See Documentation/x86/boot.txt and
Documentation/svga.txt.
Use vga=ask for menu.
This is actually a boot loader parameter; the value is