![Alan Cox](/assets/img/avatar_default.png)
The API and code have been through various bits of initial review by serial driver people but they definitely need to live somewhere for a while so the unconverted drivers can get knocked into shape, existing drivers that have been updated can be better tuned and bugs whacked out. This replaces the tty flip buffers with kmalloc objects in rings. In the normal situation for an IRQ driven serial port at typical speeds the behaviour is pretty much the same, two buffers end up allocated and the kernel cycles between them as before. When there are delays or at high speed we now behave far better as the buffer pool can grow a bit rather than lose characters. This also means that we can operate at higher speeds reliably. For drivers that receive characters in blocks (DMA based, USB and especially virtualisation) the layer allows a lot of driver specific code that works around the tty layer with private secondary queues to be removed. The IBM folks need this sort of layer, the smart serial port people do, the virtualisers do (because a virtualised tty typically operates at infinite speed rather than emulating 9600 baud). Finally many drivers had invalid and unsafe attempts to avoid buffer overflows by directly invoking tty methods extracted out of the innards of work queue structs. These are no longer needed and all go away. That fixes various random hangs with serial ports on overflow. The other change in here is to optimise the receive_room path that is used by some callers. It turns out that only one ldisc uses receive room except asa constant and it updates it far far less than the value is read. We thus make it a variable not a function call. I expect the code to contain bugs due to the size alone but I'll be watching and squashing them and feeding out new patches as it goes. Because the buffers now dynamically expand you should only run out of buffering when the kernel runs out of memory for real. That means a lot of the horrible hacks high performance drivers used to do just aren't needed any more. Description: tty_insert_flip_char is an old API and continues to work as before, as does tty_flip_buffer_push() [this is why many drivers dont need modification]. It does now also return the number of chars inserted There are also tty_buffer_request_room(tty, len) which asks for a buffer block of the length requested and returns the space found. This improves efficiency with hardware that knows how much to transfer. and tty_insert_flip_string_flags(tty, str, flags, len) to insert a string of characters and flags For a smart interface the usual code is len = tty_request_buffer_room(tty, amount_hardware_says); tty_insert_flip_string(tty, buffer_from_card, len); More description! At the moment tty buffers are attached directly to the tty. This is causing a lot of the problems related to tty layer locking, also problems at high speed and also with bursty data (such as occurs in virtualised environments) I'm working on ripping out the flip buffers and replacing them with a pool of dynamically allocated buffers. This allows both for old style "byte I/O" devices and also helps virtualisation and smart devices where large blocks of data suddenely materialise and need storing. So far so good. Lots of drivers reference tty->flip.*. Several of them also call directly and unsafely into function pointers it provides. This will all break. Most drivers can use tty_insert_flip_char which can be kept as an API but others need more. At the moment I've added the following interfaces, if people think more will be needed now is a good time to say int tty_buffer_request_room(tty, size) Try and ensure at least size bytes are available, returns actual room (may be zero). At the moment it just uses the flipbuf space but that will change. Repeated calls without characters being added are not cumulative. (ie if you call it with 1, 1, 1, and then 4 you'll have four characters of space. The other functions will also try and grow buffers in future but this will be a more efficient way when you know block sizes. int tty_insert_flip_char(tty, ch, flag) As before insert a character if there is room. Now returns 1 for success, 0 for failure. int tty_insert_flip_string(tty, str, len) Insert a block of non error characters. Returns the number inserted. int tty_prepare_flip_string(tty, strptr, len) Adjust the buffer to allow len characters to be added. Returns a buffer pointer in strptr and the length available. This allows for hardware that needs to use functions like insl or mencpy_fromio. Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1035 lines
38 KiB
Plaintext
1035 lines
38 KiB
Plaintext
#
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# Character device configuration
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#
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menu "Character devices"
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config VT
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bool "Virtual terminal" if EMBEDDED
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select INPUT
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default y if !VIOCONS
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---help---
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If you say Y here, you will get support for terminal devices with
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display and keyboard devices. These are called "virtual" because you
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can run several virtual terminals (also called virtual consoles) on
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one physical terminal. This is rather useful, for example one
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virtual terminal can collect system messages and warnings, another
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one can be used for a text-mode user session, and a third could run
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an X session, all in parallel. Switching between virtual terminals
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is done with certain key combinations, usually Alt-<function key>.
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The setterm command ("man setterm") can be used to change the
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properties (such as colors or beeping) of a virtual terminal. The
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man page console_codes(4) ("man console_codes") contains the special
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character sequences that can be used to change those properties
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directly. The fonts used on virtual terminals can be changed with
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the setfont ("man setfont") command and the key bindings are defined
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with the loadkeys ("man loadkeys") command.
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You need at least one virtual terminal device in order to make use
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of your keyboard and monitor. Therefore, only people configuring an
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embedded system would want to say N here in order to save some
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memory; the only way to log into such a system is then via a serial
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or network connection.
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If unsure, say Y, or else you won't be able to do much with your new
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shiny Linux system :-)
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config VT_CONSOLE
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bool "Support for console on virtual terminal" if EMBEDDED
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depends on VT
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default y
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---help---
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The system console is the device which receives all kernel messages
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and warnings and which allows logins in single user mode. If you
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answer Y here, a virtual terminal (the device used to interact with
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a physical terminal) can be used as system console. This is the most
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common mode of operations, so you should say Y here unless you want
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the kernel messages be output only to a serial port (in which case
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you should say Y to "Console on serial port", below).
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If you do say Y here, by default the currently visible virtual
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terminal (/dev/tty0) will be used as system console. You can change
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that with a kernel command line option such as "console=tty3" which
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would use the third virtual terminal as system console. (Try "man
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bootparam" or see the documentation of your boot loader (lilo or
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loadlin) about how to pass options to the kernel at boot time.)
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If unsure, say Y.
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config HW_CONSOLE
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bool
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depends on VT && !S390 && !UML
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default y
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config SERIAL_NONSTANDARD
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bool "Non-standard serial port support"
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---help---
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Say Y here if you have any non-standard serial boards -- boards
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which aren't supported using the standard "dumb" serial driver.
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This includes intelligent serial boards such as Cyclades,
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Digiboards, etc. These are usually used for systems that need many
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serial ports because they serve many terminals or dial-in
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connections.
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Note that the answer to this question won't directly affect the
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kernel: saying N will just cause the configurator to skip all
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the questions about non-standard serial boards.
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Most people can say N here.
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config COMPUTONE
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tristate "Computone IntelliPort Plus serial support"
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depends on SERIAL_NONSTANDARD
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---help---
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This driver supports the entire family of Intelliport II/Plus
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controllers with the exception of the MicroChannel controllers and
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products previous to the Intelliport II. These are multiport cards,
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which give you many serial ports. You would need something like this
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to connect more than two modems to your Linux box, for instance in
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order to become a dial-in server. If you have a card like that, say
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Y here and read <file:Documentation/computone.txt>.
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To compile this driver as modules, choose M here: the
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modules will be called ip2 and ip2main.
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config ROCKETPORT
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tristate "Comtrol RocketPort support"
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depends on SERIAL_NONSTANDARD
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help
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This driver supports Comtrol RocketPort and RocketModem PCI boards.
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These boards provide 2, 4, 8, 16, or 32 high-speed serial ports or
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modems. For information about the RocketPort/RocketModem boards
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and this driver read <file:Documentation/rocket.txt>.
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To compile this driver as a module, choose M here: the
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module will be called rocket.
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If you want to compile this driver into the kernel, say Y here. If
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you don't have a Comtrol RocketPort/RocketModem card installed, say N.
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config CYCLADES
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tristate "Cyclades async mux support"
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depends on SERIAL_NONSTANDARD
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---help---
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This driver supports Cyclades Z and Y multiserial boards.
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You would need something like this to connect more than two modems to
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your Linux box, for instance in order to become a dial-in server.
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For information about the Cyclades-Z card, read
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<file:drivers/char/README.cycladesZ>.
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To compile this driver as a module, choose M here: the
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module will be called cyclades.
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If you haven't heard about it, it's safe to say N.
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config CYZ_INTR
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bool "Cyclades-Z interrupt mode operation (EXPERIMENTAL)"
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depends on EXPERIMENTAL && CYCLADES
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help
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The Cyclades-Z family of multiport cards allows 2 (two) driver op
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modes: polling and interrupt. In polling mode, the driver will check
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the status of the Cyclades-Z ports every certain amount of time
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(which is called polling cycle and is configurable). In interrupt
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mode, it will use an interrupt line (IRQ) in order to check the
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status of the Cyclades-Z ports. The default op mode is polling. If
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unsure, say N.
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config DIGIEPCA
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tristate "Digiboard Intelligent Async Support"
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depends on SERIAL_NONSTANDARD
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---help---
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This is a driver for Digi International's Xx, Xeve, and Xem series
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of cards which provide multiple serial ports. You would need
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something like this to connect more than two modems to your Linux
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box, for instance in order to become a dial-in server. This driver
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supports the original PC (ISA) boards as well as PCI, and EISA. If
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you have a card like this, say Y here and read the file
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<file:Documentation/digiepca.txt>.
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To compile this driver as a module, choose M here: the
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module will be called epca.
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config ESPSERIAL
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tristate "Hayes ESP serial port support"
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depends on SERIAL_NONSTANDARD && ISA && ISA_DMA_API
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help
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This is a driver which supports Hayes ESP serial ports. Both single
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port cards and multiport cards are supported. Make sure to read
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<file:Documentation/hayes-esp.txt>.
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To compile this driver as a module, choose M here: the
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module will be called esp.
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If unsure, say N.
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config MOXA_INTELLIO
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tristate "Moxa Intellio support"
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depends on SERIAL_NONSTANDARD
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help
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Say Y here if you have a Moxa Intellio multiport serial card.
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To compile this driver as a module, choose M here: the
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module will be called moxa.
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config MOXA_SMARTIO
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tristate "Moxa SmartIO support"
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depends on SERIAL_NONSTANDARD
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help
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Say Y here if you have a Moxa SmartIO multiport serial card.
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This driver can also be built as a module ( = code which can be
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inserted in and removed from the running kernel whenever you want).
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The module will be called mxser. If you want to do that, say M
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here.
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config ISI
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tristate "Multi-Tech multiport card support (EXPERIMENTAL)"
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depends on SERIAL_NONSTANDARD
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help
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This is a driver for the Multi-Tech cards which provide several
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serial ports. The driver is experimental and can currently only be
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built as a module. The module will be called isicom.
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If you want to do that, choose M here.
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config SYNCLINK
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tristate "Microgate SyncLink card support"
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depends on SERIAL_NONSTANDARD && PCI && ISA_DMA_API
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help
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Provides support for the SyncLink ISA and PCI multiprotocol serial
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adapters. These adapters support asynchronous and HDLC bit
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synchronous communication up to 10Mbps (PCI adapter).
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This driver can only be built as a module ( = code which can be
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inserted in and removed from the running kernel whenever you want).
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The module will be called synclink. If you want to do that, say M
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here.
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config SYNCLINKMP
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tristate "SyncLink Multiport support"
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depends on SERIAL_NONSTANDARD
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help
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Enable support for the SyncLink Multiport (2 or 4 ports)
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serial adapter, running asynchronous and HDLC communications up
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to 2.048Mbps. Each ports is independently selectable for
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RS-232, V.35, RS-449, RS-530, and X.21
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This driver may be built as a module ( = code which can be
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inserted in and removed from the running kernel whenever you want).
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The module will be called synclinkmp. If you want to do that, say M
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here.
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config SYNCLINK_GT
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tristate "SyncLink GT/AC support"
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depends on SERIAL_NONSTANDARD
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help
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Support for SyncLink GT and SyncLink AC families of
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synchronous and asynchronous serial adapters
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manufactured by Microgate Systems, Ltd. (www.microgate.com)
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config N_HDLC
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tristate "HDLC line discipline support"
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depends on SERIAL_NONSTANDARD
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help
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Allows synchronous HDLC communications with tty device drivers that
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support synchronous HDLC such as the Microgate SyncLink adapter.
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This driver can only be built as a module ( = code which can be
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inserted in and removed from the running kernel whenever you want).
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The module will be called n_hdlc. If you want to do that, say M
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here.
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config RISCOM8
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tristate "SDL RISCom/8 card support"
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depends on SERIAL_NONSTANDARD && BROKEN_ON_SMP
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help
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This is a driver for the SDL Communications RISCom/8 multiport card,
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which gives you many serial ports. You would need something like
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this to connect more than two modems to your Linux box, for instance
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in order to become a dial-in server. If you have a card like that,
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say Y here and read the file <file:Documentation/riscom8.txt>.
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Also it's possible to say M here and compile this driver as kernel
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loadable module; the module will be called riscom8.
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config SPECIALIX
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tristate "Specialix IO8+ card support"
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depends on SERIAL_NONSTANDARD
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help
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This is a driver for the Specialix IO8+ multiport card (both the
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ISA and the PCI version) which gives you many serial ports. You
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would need something like this to connect more than two modems to
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your Linux box, for instance in order to become a dial-in server.
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If you have a card like that, say Y here and read the file
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<file:Documentation/specialix.txt>. Also it's possible to say M here
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and compile this driver as kernel loadable module which will be
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called specialix.
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config SPECIALIX_RTSCTS
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bool "Specialix DTR/RTS pin is RTS"
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depends on SPECIALIX
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help
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The Specialix IO8+ card can only support either RTS or DTR. If you
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say N here, the driver will use the pin as "DTR" when the tty is in
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software handshake mode. If you say Y here or hardware handshake is
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on, it will always be RTS. Read the file
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<file:Documentation/specialix.txt> for more information.
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config SX
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tristate "Specialix SX (and SI) card support"
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depends on SERIAL_NONSTANDARD
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help
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This is a driver for the SX and SI multiport serial cards.
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Please read the file <file:Documentation/sx.txt> for details.
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This driver can only be built as a module ( = code which can be
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inserted in and removed from the running kernel whenever you want).
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The module will be called sx. If you want to do that, say M here.
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config RIO
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tristate "Specialix RIO system support"
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depends on SERIAL_NONSTANDARD && BROKEN_ON_SMP && !64BIT
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help
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This is a driver for the Specialix RIO, a smart serial card which
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drives an outboard box that can support up to 128 ports. Product
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information is at <http://www.perle.com/support/documentation.html#multiport>.
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There are both ISA and PCI versions.
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config RIO_OLDPCI
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bool "Support really old RIO/PCI cards"
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depends on RIO
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help
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Older RIO PCI cards need some initialization-time configuration to
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determine the IRQ and some control addresses. If you have a RIO and
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this doesn't seem to work, try setting this to Y.
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config STALDRV
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bool "Stallion multiport serial support"
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depends on SERIAL_NONSTANDARD
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help
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Stallion cards give you many serial ports. You would need something
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like this to connect more than two modems to your Linux box, for
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instance in order to become a dial-in server. If you say Y here,
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you will be asked for your specific card model in the next
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questions. Make sure to read <file:Documentation/stallion.txt> in
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this case. If you have never heard about all this, it's safe to
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say N.
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config STALLION
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tristate "Stallion EasyIO or EC8/32 support"
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depends on STALDRV && BROKEN_ON_SMP
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help
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If you have an EasyIO or EasyConnection 8/32 multiport Stallion
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card, then this is for you; say Y. Make sure to read
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<file:Documentation/stallion.txt>.
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To compile this driver as a module, choose M here: the
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module will be called stallion.
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config ISTALLION
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tristate "Stallion EC8/64, ONboard, Brumby support"
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depends on STALDRV && BROKEN_ON_SMP
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help
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If you have an EasyConnection 8/64, ONboard, Brumby or Stallion
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serial multiport card, say Y here. Make sure to read
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<file:Documentation/stallion.txt>.
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To compile this driver as a module, choose M here: the
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module will be called istallion.
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config AU1000_UART
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bool "Enable Au1000 UART Support"
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depends on SERIAL_NONSTANDARD && MIPS
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help
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If you have an Alchemy AU1000 processor (MIPS based) and you want
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to use serial ports, say Y. Otherwise, say N.
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config AU1000_SERIAL_CONSOLE
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bool "Enable Au1000 serial console"
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depends on AU1000_UART
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help
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If you have an Alchemy AU1000 processor (MIPS based) and you want
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to use a console on a serial port, say Y. Otherwise, say N.
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config QTRONIX_KEYBOARD
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bool "Enable Qtronix 990P Keyboard Support"
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depends on IT8712
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help
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Images of Qtronix keyboards are at
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<http://www.qtronix.com/keyboard.html>.
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config IT8172_CIR
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bool
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depends on QTRONIX_KEYBOARD
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default y
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config IT8172_SCR0
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bool "Enable Smart Card Reader 0 Support "
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depends on IT8712
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help
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Say Y here to support smart-card reader 0 (SCR0) on the Integrated
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Technology Express, Inc. ITE8172 SBC. Vendor page at
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<http://www.ite.com.tw/ia/brief_it8172bsp.htm>; picture of the
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board at <http://www.mvista.com/partners/semiconductor/ite.html>.
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config IT8172_SCR1
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bool "Enable Smart Card Reader 1 Support "
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depends on IT8712
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help
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Say Y here to support smart-card reader 1 (SCR1) on the Integrated
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Technology Express, Inc. ITE8172 SBC. Vendor page at
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<http://www.ite.com.tw/ia/brief_it8172bsp.htm>; picture of the
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board at <http://www.mvista.com/partners/semiconductor/ite.html>.
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config A2232
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tristate "Commodore A2232 serial support (EXPERIMENTAL)"
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depends on EXPERIMENTAL && ZORRO && BROKEN_ON_SMP
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---help---
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This option supports the 2232 7-port serial card shipped with the
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Amiga 2000 and other Zorro-bus machines, dating from 1989. At
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a max of 19,200 bps, the ports are served by a 6551 ACIA UART chip
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each, plus a 8520 CIA, and a master 6502 CPU and buffer as well. The
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ports were connected with 8 pin DIN connectors on the card bracket,
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for which 8 pin to DB25 adapters were supplied. The card also had
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jumpers internally to toggle various pinning configurations.
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This driver can be built as a module; but then "generic_serial"
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will also be built as a module. This has to be loaded before
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"ser_a2232". If you want to do this, answer M here.
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config SGI_SNSC
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bool "SGI Altix system controller communication support"
|
|
depends on (IA64_SGI_SN2 || IA64_GENERIC)
|
|
help
|
|
If you have an SGI Altix and you want to enable system
|
|
controller communication from user space (you want this!),
|
|
say Y. Otherwise, say N.
|
|
|
|
config SGI_TIOCX
|
|
bool "SGI TIO CX driver support"
|
|
depends on (IA64_SGI_SN2 || IA64_GENERIC)
|
|
help
|
|
If you have an SGI Altix and you have fpga devices attached
|
|
to your TIO, say Y here, otherwise say N.
|
|
|
|
config SGI_MBCS
|
|
tristate "SGI FPGA Core Services driver support"
|
|
depends on SGI_TIOCX
|
|
help
|
|
If you have an SGI Altix with an attached SABrick
|
|
say Y or M here, otherwise say N.
|
|
|
|
source "drivers/serial/Kconfig"
|
|
|
|
config UNIX98_PTYS
|
|
bool "Unix98 PTY support" if EMBEDDED
|
|
default y
|
|
---help---
|
|
A pseudo terminal (PTY) is a software device consisting of two
|
|
halves: a master and a slave. The slave device behaves identical to
|
|
a physical terminal; the master device is used by a process to
|
|
read data from and write data to the slave, thereby emulating a
|
|
terminal. Typical programs for the master side are telnet servers
|
|
and xterms.
|
|
|
|
Linux has traditionally used the BSD-like names /dev/ptyxx for
|
|
masters and /dev/ttyxx for slaves of pseudo terminals. This scheme
|
|
has a number of problems. The GNU C library glibc 2.1 and later,
|
|
however, supports the Unix98 naming standard: in order to acquire a
|
|
pseudo terminal, a process opens /dev/ptmx; the number of the pseudo
|
|
terminal is then made available to the process and the pseudo
|
|
terminal slave can be accessed as /dev/pts/<number>. What was
|
|
traditionally /dev/ttyp2 will then be /dev/pts/2, for example.
|
|
|
|
All modern Linux systems use the Unix98 ptys. Say Y unless
|
|
you're on an embedded system and want to conserve memory.
|
|
|
|
config LEGACY_PTYS
|
|
bool "Legacy (BSD) PTY support"
|
|
default y
|
|
---help---
|
|
A pseudo terminal (PTY) is a software device consisting of two
|
|
halves: a master and a slave. The slave device behaves identical to
|
|
a physical terminal; the master device is used by a process to
|
|
read data from and write data to the slave, thereby emulating a
|
|
terminal. Typical programs for the master side are telnet servers
|
|
and xterms.
|
|
|
|
Linux has traditionally used the BSD-like names /dev/ptyxx
|
|
for masters and /dev/ttyxx for slaves of pseudo
|
|
terminals. This scheme has a number of problems, including
|
|
security. This option enables these legacy devices; on most
|
|
systems, it is safe to say N.
|
|
|
|
|
|
config LEGACY_PTY_COUNT
|
|
int "Maximum number of legacy PTY in use"
|
|
depends on LEGACY_PTYS
|
|
range 1 256
|
|
default "256"
|
|
---help---
|
|
The maximum number of legacy PTYs that can be used at any one time.
|
|
The default is 256, and should be more than enough. Embedded
|
|
systems may want to reduce this to save memory.
|
|
|
|
When not in use, each legacy PTY occupies 12 bytes on 32-bit
|
|
architectures and 24 bytes on 64-bit architectures.
|
|
|
|
config PRINTER
|
|
tristate "Parallel printer support"
|
|
depends on PARPORT
|
|
---help---
|
|
If you intend to attach a printer to the parallel port of your Linux
|
|
box (as opposed to using a serial printer; if the connector at the
|
|
printer has 9 or 25 holes ["female"], then it's serial), say Y.
|
|
Also read the Printing-HOWTO, available from
|
|
<http://www.tldp.org/docs.html#howto>.
|
|
|
|
It is possible to share one parallel port among several devices
|
|
(e.g. printer and ZIP drive) and it is safe to compile the
|
|
corresponding drivers into the kernel.
|
|
|
|
To compile this driver as a module, choose M here and read
|
|
<file:Documentation/parport.txt>. The module will be called lp.
|
|
|
|
If you have several parallel ports, you can specify which ports to
|
|
use with the "lp" kernel command line option. (Try "man bootparam"
|
|
or see the documentation of your boot loader (lilo or loadlin) about
|
|
how to pass options to the kernel at boot time.) The syntax of the
|
|
"lp" command line option can be found in <file:drivers/char/lp.c>.
|
|
|
|
If you have more than 8 printers, you need to increase the LP_NO
|
|
macro in lp.c and the PARPORT_MAX macro in parport.h.
|
|
|
|
config LP_CONSOLE
|
|
bool "Support for console on line printer"
|
|
depends on PRINTER
|
|
---help---
|
|
If you want kernel messages to be printed out as they occur, you
|
|
can have a console on the printer. This option adds support for
|
|
doing that; to actually get it to happen you need to pass the
|
|
option "console=lp0" to the kernel at boot time.
|
|
|
|
If the printer is out of paper (or off, or unplugged, or too
|
|
busy..) the kernel will stall until the printer is ready again.
|
|
By defining CONSOLE_LP_STRICT to 0 (at your own risk) you
|
|
can make the kernel continue when this happens,
|
|
but it'll lose the kernel messages.
|
|
|
|
If unsure, say N.
|
|
|
|
config PPDEV
|
|
tristate "Support for user-space parallel port device drivers"
|
|
depends on PARPORT
|
|
---help---
|
|
Saying Y to this adds support for /dev/parport device nodes. This
|
|
is needed for programs that want portable access to the parallel
|
|
port, for instance deviceid (which displays Plug-and-Play device
|
|
IDs).
|
|
|
|
This is the parallel port equivalent of SCSI generic support (sg).
|
|
It is safe to say N to this -- it is not needed for normal printing
|
|
or parallel port CD-ROM/disk support.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called ppdev.
|
|
|
|
If unsure, say N.
|
|
|
|
config TIPAR
|
|
tristate "Texas Instruments parallel link cable support"
|
|
depends on PARPORT
|
|
---help---
|
|
If you own a Texas Instruments graphing calculator and use a
|
|
parallel link cable, then you might be interested in this driver.
|
|
|
|
If you enable this driver, you will be able to communicate with
|
|
your calculator through a set of device nodes under /dev. The
|
|
main advantage of this driver is that you don't have to be root
|
|
to use this precise link cable (depending on the permissions on
|
|
the device nodes, though).
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called tipar.
|
|
|
|
If you don't know what a parallel link cable is or what a Texas
|
|
Instruments graphing calculator is, then you probably don't need this
|
|
driver.
|
|
|
|
If unsure, say N.
|
|
|
|
config HVC_CONSOLE
|
|
bool "pSeries Hypervisor Virtual Console support"
|
|
depends on PPC_PSERIES
|
|
help
|
|
pSeries machines when partitioned support a hypervisor virtual
|
|
console. This driver allows each pSeries partition to have a console
|
|
which is accessed via the HMC.
|
|
|
|
config HVCS
|
|
tristate "IBM Hypervisor Virtual Console Server support"
|
|
depends on PPC_PSERIES
|
|
help
|
|
Partitionable IBM Power5 ppc64 machines allow hosting of
|
|
firmware virtual consoles from one Linux partition by
|
|
another Linux partition. This driver allows console data
|
|
from Linux partitions to be accessed through TTY device
|
|
interfaces in the device tree of a Linux partition running
|
|
this driver.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called hvcs.ko. Additionally, this module
|
|
will depend on arch specific APIs exported from hvcserver.ko
|
|
which will also be compiled when this driver is built as a
|
|
module.
|
|
|
|
source "drivers/char/ipmi/Kconfig"
|
|
|
|
source "drivers/char/watchdog/Kconfig"
|
|
|
|
config DS1620
|
|
tristate "NetWinder thermometer support"
|
|
depends on ARCH_NETWINDER
|
|
help
|
|
Say Y here to include support for the thermal management hardware
|
|
found in the NetWinder. This driver allows the user to control the
|
|
temperature set points and to read the current temperature.
|
|
|
|
It is also possible to say M here to build it as a module (ds1620)
|
|
It is recommended to be used on a NetWinder, but it is not a
|
|
necessity.
|
|
|
|
config NWBUTTON
|
|
tristate "NetWinder Button"
|
|
depends on ARCH_NETWINDER
|
|
---help---
|
|
If you say Y here and create a character device node /dev/nwbutton
|
|
with major and minor numbers 10 and 158 ("man mknod"), then every
|
|
time the orange button is pressed a number of times, the number of
|
|
times the button was pressed will be written to that device.
|
|
|
|
This is most useful for applications, as yet unwritten, which
|
|
perform actions based on how many times the button is pressed in a
|
|
row.
|
|
|
|
Do not hold the button down for too long, as the driver does not
|
|
alter the behaviour of the hardware reset circuitry attached to the
|
|
button; it will still execute a hard reset if the button is held
|
|
down for longer than approximately five seconds.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called nwbutton.
|
|
|
|
Most people will answer Y to this question and "Reboot Using Button"
|
|
below to be able to initiate a system shutdown from the button.
|
|
|
|
config NWBUTTON_REBOOT
|
|
bool "Reboot Using Button"
|
|
depends on NWBUTTON
|
|
help
|
|
If you say Y here, then you will be able to initiate a system
|
|
shutdown and reboot by pressing the orange button a number of times.
|
|
The number of presses to initiate the shutdown is two by default,
|
|
but this can be altered by modifying the value of NUM_PRESSES_REBOOT
|
|
in nwbutton.h and recompiling the driver or, if you compile the
|
|
driver as a module, you can specify the number of presses at load
|
|
time with "insmod button reboot_count=<something>".
|
|
|
|
config NWFLASH
|
|
tristate "NetWinder flash support"
|
|
depends on ARCH_NETWINDER
|
|
---help---
|
|
If you say Y here and create a character device /dev/flash with
|
|
major 10 and minor 160 you can manipulate the flash ROM containing
|
|
the NetWinder firmware. Be careful as accidentally overwriting the
|
|
flash contents can render your computer unbootable. On no account
|
|
allow random users access to this device. :-)
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called nwflash.
|
|
|
|
If you're not sure, say N.
|
|
|
|
config HW_RANDOM
|
|
tristate "Intel/AMD/VIA HW Random Number Generator support"
|
|
depends on (X86 || IA64) && PCI
|
|
---help---
|
|
This driver provides kernel-side support for the Random Number
|
|
Generator hardware found on Intel i8xx-based motherboards,
|
|
AMD 76x-based motherboards, and Via Nehemiah CPUs.
|
|
|
|
Provides a character driver, used to read() entropy data.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called hw_random.
|
|
|
|
If unsure, say N.
|
|
|
|
config NVRAM
|
|
tristate "/dev/nvram support"
|
|
depends on ATARI || X86 || ARM || GENERIC_NVRAM
|
|
---help---
|
|
If you say Y here and create a character special file /dev/nvram
|
|
with major number 10 and minor number 144 using mknod ("man mknod"),
|
|
you get read and write access to the extra bytes of non-volatile
|
|
memory in the real time clock (RTC), which is contained in every PC
|
|
and most Ataris. The actual number of bytes varies, depending on the
|
|
nvram in the system, but is usually 114 (128-14 for the RTC).
|
|
|
|
This memory is conventionally called "CMOS RAM" on PCs and "NVRAM"
|
|
on Ataris. /dev/nvram may be used to view settings there, or to
|
|
change them (with some utility). It could also be used to frequently
|
|
save a few bits of very important data that may not be lost over
|
|
power-off and for which writing to disk is too insecure. Note
|
|
however that most NVRAM space in a PC belongs to the BIOS and you
|
|
should NEVER idly tamper with it. See Ralf Brown's interrupt list
|
|
for a guide to the use of CMOS bytes by your BIOS.
|
|
|
|
On Atari machines, /dev/nvram is always configured and does not need
|
|
to be selected.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called nvram.
|
|
|
|
config RTC
|
|
tristate "Enhanced Real Time Clock Support"
|
|
depends on !PPC32 && !PARISC && !IA64 && !M68K && (!SPARC || PCI) && !FRV
|
|
---help---
|
|
If you say Y here and create a character special file /dev/rtc with
|
|
major number 10 and minor number 135 using mknod ("man mknod"), you
|
|
will get access to the real time clock (or hardware clock) built
|
|
into your computer.
|
|
|
|
Every PC has such a clock built in. It can be used to generate
|
|
signals from as low as 1Hz up to 8192Hz, and can also be used
|
|
as a 24 hour alarm. It reports status information via the file
|
|
/proc/driver/rtc and its behaviour is set by various ioctls on
|
|
/dev/rtc.
|
|
|
|
If you run Linux on a multiprocessor machine and said Y to
|
|
"Symmetric Multi Processing" above, you should say Y here to read
|
|
and set the RTC in an SMP compatible fashion.
|
|
|
|
If you think you have a use for such a device (such as periodic data
|
|
sampling), then say Y here, and read <file:Documentation/rtc.txt>
|
|
for details.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called rtc.
|
|
|
|
config SGI_DS1286
|
|
tristate "SGI DS1286 RTC support"
|
|
depends on SGI_IP22
|
|
help
|
|
If you say Y here and create a character special file /dev/rtc with
|
|
major number 10 and minor number 135 using mknod ("man mknod"), you
|
|
will get access to the real time clock built into your computer.
|
|
Every SGI has such a clock built in. It reports status information
|
|
via the file /proc/rtc and its behaviour is set by various ioctls on
|
|
/dev/rtc.
|
|
|
|
config SGI_IP27_RTC
|
|
bool "SGI M48T35 RTC support"
|
|
depends on SGI_IP27
|
|
help
|
|
If you say Y here and create a character special file /dev/rtc with
|
|
major number 10 and minor number 135 using mknod ("man mknod"), you
|
|
will get access to the real time clock built into your computer.
|
|
Every SGI has such a clock built in. It reports status information
|
|
via the file /proc/rtc and its behaviour is set by various ioctls on
|
|
/dev/rtc.
|
|
|
|
config GEN_RTC
|
|
tristate "Generic /dev/rtc emulation"
|
|
depends on RTC!=y && !IA64 && !ARM && !M32R && !SPARC && !FRV
|
|
---help---
|
|
If you say Y here and create a character special file /dev/rtc with
|
|
major number 10 and minor number 135 using mknod ("man mknod"), you
|
|
will get access to the real time clock (or hardware clock) built
|
|
into your computer.
|
|
|
|
It reports status information via the file /proc/driver/rtc and its
|
|
behaviour is set by various ioctls on /dev/rtc. If you enable the
|
|
"extended RTC operation" below it will also provide an emulation
|
|
for RTC_UIE which is required by some programs and may improve
|
|
precision in some cases.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called genrtc.
|
|
|
|
config GEN_RTC_X
|
|
bool "Extended RTC operation"
|
|
depends on GEN_RTC
|
|
help
|
|
Provides an emulation for RTC_UIE which is required by some programs
|
|
and may improve precision of the generic RTC support in some cases.
|
|
|
|
config EFI_RTC
|
|
bool "EFI Real Time Clock Services"
|
|
depends on IA64
|
|
|
|
config DS1302
|
|
tristate "DS1302 RTC support"
|
|
depends on M32R && (PLAT_M32700UT || PLAT_OPSPUT)
|
|
help
|
|
If you say Y here and create a character special file /dev/rtc with
|
|
major number 121 and minor number 0 using mknod ("man mknod"), you
|
|
will get access to the real time clock (or hardware clock) built
|
|
into your computer.
|
|
|
|
config S3C2410_RTC
|
|
bool "S3C2410 RTC Driver"
|
|
depends on ARCH_S3C2410
|
|
help
|
|
RTC (Realtime Clock) driver for the clock inbuilt into the
|
|
Samsung S3C2410. This can provide periodic interrupt rates
|
|
from 1Hz to 64Hz for user programs, and wakeup from Alarm.
|
|
|
|
config RTC_VR41XX
|
|
tristate "NEC VR4100 series Real Time Clock Support"
|
|
depends on CPU_VR41XX
|
|
|
|
config COBALT_LCD
|
|
bool "Support for Cobalt LCD"
|
|
depends on MIPS_COBALT
|
|
help
|
|
This option enables support for the LCD display and buttons found
|
|
on Cobalt systems through a misc device.
|
|
|
|
config DTLK
|
|
tristate "Double Talk PC internal speech card support"
|
|
help
|
|
This driver is for the DoubleTalk PC, a speech synthesizer
|
|
manufactured by RC Systems (<http://www.rcsys.com/>). It is also
|
|
called the `internal DoubleTalk'.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called dtlk.
|
|
|
|
config R3964
|
|
tristate "Siemens R3964 line discipline"
|
|
---help---
|
|
This driver allows synchronous communication with devices using the
|
|
Siemens R3964 packet protocol. Unless you are dealing with special
|
|
hardware like PLCs, you are unlikely to need this.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called n_r3964.
|
|
|
|
If unsure, say N.
|
|
|
|
config APPLICOM
|
|
tristate "Applicom intelligent fieldbus card support"
|
|
depends on PCI
|
|
---help---
|
|
This driver provides the kernel-side support for the intelligent
|
|
fieldbus cards made by Applicom International. More information
|
|
about these cards can be found on the WWW at the address
|
|
<http://www.applicom-int.com/>, or by email from David Woodhouse
|
|
<dwmw2@infradead.org>.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called applicom.
|
|
|
|
If unsure, say N.
|
|
|
|
config SONYPI
|
|
tristate "Sony Vaio Programmable I/O Control Device support (EXPERIMENTAL)"
|
|
depends on EXPERIMENTAL && X86 && PCI && INPUT && !64BIT
|
|
---help---
|
|
This driver enables access to the Sony Programmable I/O Control
|
|
Device which can be found in many (all ?) Sony Vaio laptops.
|
|
|
|
If you have one of those laptops, read
|
|
<file:Documentation/sonypi.txt>, and say Y or M here.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called sonypi.
|
|
|
|
config TANBAC_TB0219
|
|
tristate "TANBAC TB0219 base board support"
|
|
depends TANBAC_TB022X
|
|
|
|
menu "Ftape, the floppy tape device driver"
|
|
|
|
config FTAPE
|
|
tristate "Ftape (QIC-80/Travan) support"
|
|
depends on BROKEN_ON_SMP && (ALPHA || X86)
|
|
---help---
|
|
If you have a tape drive that is connected to your floppy
|
|
controller, say Y here.
|
|
|
|
Some tape drives (like the Seagate "Tape Store 3200" or the Iomega
|
|
"Ditto 3200" or the Exabyte "Eagle TR-3") come with a "high speed"
|
|
controller of their own. These drives (and their companion
|
|
controllers) are also supported if you say Y here.
|
|
|
|
If you have a special controller (such as the CMS FC-10, FC-20,
|
|
Mountain Mach-II, or any controller that is based on the Intel 82078
|
|
FDC like the high speed controllers by Seagate and Exabyte and
|
|
Iomega's "Ditto Dash") you must configure it by selecting the
|
|
appropriate entries from the "Floppy tape controllers" sub-menu
|
|
below and possibly modify the default values for the IRQ and DMA
|
|
channel and the IO base in ftape's configuration menu.
|
|
|
|
If you want to use your floppy tape drive on a PCI-bus based system,
|
|
please read the file <file:drivers/char/ftape/README.PCI>.
|
|
|
|
The ftape kernel driver is also available as a runtime loadable
|
|
module. To compile this driver as a module, choose M here: the
|
|
module will be called ftape.
|
|
|
|
Note that the Ftape-HOWTO is out of date (sorry) and documents the
|
|
older version 2.08 of this software but still contains useful
|
|
information. There is a web page with more recent documentation at
|
|
<http://www.instmath.rwth-aachen.de/~heine/ftape/>. This page
|
|
always contains the latest release of the ftape driver and useful
|
|
information (backup software, ftape related patches and
|
|
documentation, FAQ). Note that the file system interface has
|
|
changed quite a bit compared to previous versions of ftape. Please
|
|
read <file:Documentation/ftape.txt>.
|
|
|
|
source "drivers/char/ftape/Kconfig"
|
|
|
|
endmenu
|
|
|
|
source "drivers/char/agp/Kconfig"
|
|
|
|
source "drivers/char/drm/Kconfig"
|
|
|
|
source "drivers/char/pcmcia/Kconfig"
|
|
|
|
config MWAVE
|
|
tristate "ACP Modem (Mwave) support"
|
|
depends on X86
|
|
select SERIAL_8250
|
|
---help---
|
|
The ACP modem (Mwave) for Linux is a WinModem. It is composed of a
|
|
kernel driver and a user level application. Together these components
|
|
support direct attachment to public switched telephone networks (PSTNs)
|
|
and support selected world wide countries.
|
|
|
|
This version of the ACP Modem driver supports the IBM Thinkpad 600E,
|
|
600, and 770 that include on board ACP modem hardware.
|
|
|
|
The modem also supports the standard communications port interface
|
|
(ttySx) and is compatible with the Hayes AT Command Set.
|
|
|
|
The user level application needed to use this driver can be found at
|
|
the IBM Linux Technology Center (LTC) web site:
|
|
<http://www.ibm.com/linux/ltc/>.
|
|
|
|
If you own one of the above IBM Thinkpads which has the Mwave chipset
|
|
in it, say Y.
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
module will be called mwave.
|
|
|
|
config SCx200_GPIO
|
|
tristate "NatSemi SCx200 GPIO Support"
|
|
depends on SCx200
|
|
help
|
|
Give userspace access to the GPIO pins on the National
|
|
Semiconductor SCx200 processors.
|
|
|
|
If compiled as a module, it will be called scx200_gpio.
|
|
|
|
config CS5535_GPIO
|
|
tristate "AMD CS5535/CS5536 GPIO (Geode Companion Device)"
|
|
depends on X86_32
|
|
help
|
|
Give userspace access to the GPIO pins on the AMD CS5535 and
|
|
CS5536 Geode companion devices.
|
|
|
|
If compiled as a module, it will be called cs5535_gpio.
|
|
|
|
config GPIO_VR41XX
|
|
tristate "NEC VR4100 series General-purpose I/O Unit support"
|
|
depends on CPU_VR41XX
|
|
|
|
config RAW_DRIVER
|
|
tristate "RAW driver (/dev/raw/rawN) (OBSOLETE)"
|
|
help
|
|
The raw driver permits block devices to be bound to /dev/raw/rawN.
|
|
Once bound, I/O against /dev/raw/rawN uses efficient zero-copy I/O.
|
|
See the raw(8) manpage for more details.
|
|
|
|
The raw driver is deprecated and will be removed soon.
|
|
Applications should simply open the device (eg /dev/hda1)
|
|
with the O_DIRECT flag.
|
|
|
|
config MAX_RAW_DEVS
|
|
int "Maximum number of RAW devices to support (1-8192)"
|
|
depends on RAW_DRIVER
|
|
default "256"
|
|
help
|
|
The maximum number of RAW devices that are supported.
|
|
Default is 256. Increase this number in case you need lots of
|
|
raw devices.
|
|
|
|
config HPET
|
|
bool "HPET - High Precision Event Timer" if (X86 || IA64)
|
|
default n
|
|
depends on ACPI
|
|
help
|
|
If you say Y here, you will have a miscdevice named "/dev/hpet/". Each
|
|
open selects one of the timers supported by the HPET. The timers are
|
|
non-periodioc and/or periodic.
|
|
|
|
config HPET_RTC_IRQ
|
|
bool "HPET Control RTC IRQ" if !HPET_EMULATE_RTC
|
|
default n
|
|
depends on HPET
|
|
help
|
|
If you say Y here, you will disable RTC_IRQ in drivers/char/rtc.c. It
|
|
is assumed the platform called hpet_alloc with the RTC IRQ values for
|
|
the HPET timers.
|
|
|
|
config HPET_MMAP
|
|
bool "Allow mmap of HPET"
|
|
default y
|
|
depends on HPET
|
|
help
|
|
If you say Y here, user applications will be able to mmap
|
|
the HPET registers.
|
|
|
|
In some hardware implementations, the page containing HPET
|
|
registers may also contain other things that shouldn't be
|
|
exposed to the user. If this applies to your hardware,
|
|
say N here.
|
|
|
|
config HANGCHECK_TIMER
|
|
tristate "Hangcheck timer"
|
|
depends on X86 || IA64 || PPC64 || S390
|
|
help
|
|
The hangcheck-timer module detects when the system has gone
|
|
out to lunch past a certain margin. It can reboot the system
|
|
or merely print a warning.
|
|
|
|
config MMTIMER
|
|
tristate "MMTIMER Memory mapped RTC for SGI Altix"
|
|
depends on IA64_GENERIC || IA64_SGI_SN2
|
|
default y
|
|
help
|
|
The mmtimer device allows direct userspace access to the
|
|
Altix system timer.
|
|
|
|
source "drivers/char/tpm/Kconfig"
|
|
|
|
config TELCLOCK
|
|
tristate "Telecom clock driver for MPBL0010 ATCA SBC"
|
|
depends on EXPERIMENTAL
|
|
default n
|
|
help
|
|
The telecom clock device is specific to the MPBL0010 ATCA computer and
|
|
allows direct userspace access to the configuration of the telecom clock
|
|
configuration settings. This device is used for hardware synchronization
|
|
across the ATCA backplane fabric. Upon loading, the driver exports a
|
|
sysfs directory, /sys/devices/platform/telco_clock, with a number of
|
|
files for controlling the behavior of this hardware.
|
|
|
|
endmenu
|
|
|