2 # Character device configuration
5 menu "Character devices"
8 bool "Virtual terminal" if EMBEDDED
12 If you say Y here, you will get support for terminal devices with
13 display and keyboard devices. These are called "virtual" because you
14 can run several virtual terminals (also called virtual consoles) on
15 one physical terminal. This is rather useful, for example one
16 virtual terminal can collect system messages and warnings, another
17 one can be used for a text-mode user session, and a third could run
18 an X session, all in parallel. Switching between virtual terminals
19 is done with certain key combinations, usually Alt-<function key>.
21 The setterm command ("man setterm") can be used to change the
22 properties (such as colors or beeping) of a virtual terminal. The
23 man page console_codes(4) ("man console_codes") contains the special
24 character sequences that can be used to change those properties
25 directly. The fonts used on virtual terminals can be changed with
26 the setfont ("man setfont") command and the key bindings are defined
27 with the loadkeys ("man loadkeys") command.
29 You need at least one virtual terminal device in order to make use
30 of your keyboard and monitor. Therefore, only people configuring an
31 embedded system would want to say N here in order to save some
32 memory; the only way to log into such a system is then via a serial
33 or network connection.
35 If unsure, say Y, or else you won't be able to do much with your new
36 shiny Linux system :-)
39 bool "Support for console on virtual terminal" if EMBEDDED
43 The system console is the device which receives all kernel messages
44 and warnings and which allows logins in single user mode. If you
45 answer Y here, a virtual terminal (the device used to interact with
46 a physical terminal) can be used as system console. This is the most
47 common mode of operations, so you should say Y here unless you want
48 the kernel messages be output only to a serial port (in which case
49 you should say Y to "Console on serial port", below).
51 If you do say Y here, by default the currently visible virtual
52 terminal (/dev/tty0) will be used as system console. You can change
53 that with a kernel command line option such as "console=tty3" which
54 would use the third virtual terminal as system console. (Try "man
55 bootparam" or see the documentation of your boot loader (lilo or
56 loadlin) about how to pass options to the kernel at boot time.)
62 depends on VT && !S390 && !UM
65 config SERIAL_NONSTANDARD
66 bool "Non-standard serial port support"
68 Say Y here if you have any non-standard serial boards -- boards
69 which aren't supported using the standard "dumb" serial driver.
70 This includes intelligent serial boards such as Cyclades,
71 Digiboards, etc. These are usually used for systems that need many
72 serial ports because they serve many terminals or dial-in
75 Note that the answer to this question won't directly affect the
76 kernel: saying N will just cause the configurator to skip all
77 the questions about non-standard serial boards.
79 Most people can say N here.
82 tristate "Computone IntelliPort Plus serial support"
83 depends on SERIAL_NONSTANDARD && BROKEN_ON_SMP
85 This driver supports the entire family of Intelliport II/Plus
86 controllers with the exception of the MicroChannel controllers and
87 products previous to the Intelliport II. These are multiport cards,
88 which give you many serial ports. You would need something like this
89 to connect more than two modems to your Linux box, for instance in
90 order to become a dial-in server. If you have a card like that, say
91 Y here and read <file:Documentation/computone.txt>.
93 To compile this driver as modules, choose M here: the
94 modules will be called ip2 and ip2main.
97 tristate "Comtrol RocketPort support"
98 depends on SERIAL_NONSTANDARD
100 This driver supports Comtrol RocketPort and RocketModem PCI boards.
101 These boards provide 2, 4, 8, 16, or 32 high-speed serial ports or
102 modems. For information about the RocketPort/RocketModem boards
103 and this driver read <file:Documentation/rocket.txt>.
105 To compile this driver as a module, choose M here: the
106 module will be called rocket.
108 If you want to compile this driver into the kernel, say Y here. If
109 you don't have a Comtrol RocketPort/RocketModem card installed, say N.
112 tristate "Cyclades async mux support"
113 depends on SERIAL_NONSTANDARD
115 This driver supports Cyclades Z and Y multiserial boards.
116 You would need something like this to connect more than two modems to
117 your Linux box, for instance in order to become a dial-in server.
119 For information about the Cyclades-Z card, read
120 <file:drivers/char/README.cycladesZ>.
122 To compile this driver as a module, choose M here: the
123 module will be called cyclades.
125 If you haven't heard about it, it's safe to say N.
128 bool "Cyclades-Z interrupt mode operation (EXPERIMENTAL)"
129 depends on EXPERIMENTAL && CYCLADES
131 The Cyclades-Z family of multiport cards allows 2 (two) driver op
132 modes: polling and interrupt. In polling mode, the driver will check
133 the status of the Cyclades-Z ports every certain amount of time
134 (which is called polling cycle and is configurable). In interrupt
135 mode, it will use an interrupt line (IRQ) in order to check the
136 status of the Cyclades-Z ports. The default op mode is polling. If
140 tristate "Digiboard Intelligent Async Support"
141 depends on SERIAL_NONSTANDARD && BROKEN_ON_SMP
143 This is a driver for Digi International's Xx, Xeve, and Xem series
144 of cards which provide multiple serial ports. You would need
145 something like this to connect more than two modems to your Linux
146 box, for instance in order to become a dial-in server. This driver
147 supports the original PC (ISA) boards as well as PCI, and EISA. If
148 you have a card like this, say Y here and read the file
149 <file:Documentation/digiepca.txt>.
151 NOTE: There is another, separate driver for the Digiboard PC boards:
152 "Digiboard PC/Xx Support" below. You should (and can) only select
153 one of the two drivers.
155 To compile this driver as a module, choose M here: the
156 module will be called epca.
159 tristate "Digiboard PC/Xx Support"
160 depends on SERIAL_NONSTANDARD && DIGIEPCA=n && BROKEN_ON_SMP
162 This is a driver for the Digiboard PC/Xe, PC/Xi, and PC/Xeve cards
163 that give you many serial ports. You would need something like this
164 to connect more than two modems to your Linux box, for instance in
165 order to become a dial-in server. If you have a card like that, say
166 Y here and read the file <file:Documentation/digiboard.txt>.
168 To compile this driver as a module, choose M here: the
169 module will be called pcxx.
172 tristate "Hayes ESP serial port support"
173 depends on SERIAL_NONSTANDARD && ISA && BROKEN_ON_SMP
175 This is a driver which supports Hayes ESP serial ports. Both single
176 port cards and multiport cards are supported. Make sure to read
177 <file:Documentation/hayes-esp.txt>.
179 To compile this driver as a module, choose M here: the
180 module will be called esp.
185 tristate "Moxa Intellio support"
186 depends on SERIAL_NONSTANDARD && BROKEN_ON_SMP
188 Say Y here if you have a Moxa Intellio multiport serial card.
190 To compile this driver as a module, choose M here: the
191 module will be called moxa.
194 tristate "Moxa SmartIO support"
195 depends on SERIAL_NONSTANDARD && BROKEN_ON_SMP
197 Say Y here if you have a Moxa SmartIO multiport serial card.
199 This driver can also be built as a module ( = code which can be
200 inserted in and removed from the running kernel whenever you want).
201 The module will be called mxser. If you want to do that, say M
205 tristate "Multi-Tech multiport card support (EXPERIMENTAL)"
206 depends on SERIAL_NONSTANDARD && PCI && EXPERIMENTAL && BROKEN_ON_SMP && m
208 This is a driver for the Multi-Tech cards which provide several
209 serial ports. The driver is experimental and can currently only be
210 built as a module. The module will be called isicom.
211 If you want to do that, choose M here.
214 tristate "Microgate SyncLink card support"
215 depends on SERIAL_NONSTANDARD && PCI
217 Provides support for the SyncLink ISA and PCI multiprotocol serial
218 adapters. These adapters support asynchronous and HDLC bit
219 synchronous communication up to 10Mbps (PCI adapter).
221 This driver can only be built as a module ( = code which can be
222 inserted in and removed from the running kernel whenever you want).
223 The module will be called synclink. If you want to do that, say M
227 tristate "SyncLink Multiport support"
228 depends on SERIAL_NONSTANDARD
230 Enable support for the SyncLink Multiport (2 or 4 ports)
231 serial adapter, running asynchronous and HDLC communications up
232 to 2.048Mbps. Each ports is independently selectable for
233 RS-232, V.35, RS-449, RS-530, and X.21
235 This driver may be built as a module ( = code which can be
236 inserted in and removed from the running kernel whenever you want).
237 The module will be called synclinkmp. If you want to do that, say M
241 tristate "HDLC line discipline support"
242 depends on SERIAL_NONSTANDARD
244 Allows synchronous HDLC communications with tty device drivers that
245 support synchronous HDLC such as the Microgate SyncLink adapter.
247 This driver can only be built as a module ( = code which can be
248 inserted in and removed from the running kernel whenever you want).
249 The module will be called n_hdlc. If you want to do that, say M
253 tristate "SDL RISCom/8 card support"
254 depends on SERIAL_NONSTANDARD && BROKEN_ON_SMP
256 This is a driver for the SDL Communications RISCom/8 multiport card,
257 which gives you many serial ports. You would need something like
258 this to connect more than two modems to your Linux box, for instance
259 in order to become a dial-in server. If you have a card like that,
260 say Y here and read the file <file:Documentation/riscom8.txt>.
262 Also it's possible to say M here and compile this driver as kernel
263 loadable module; the module will be called riscom8.
266 tristate "Specialix IO8+ card support"
267 depends on SERIAL_NONSTANDARD && BROKEN_ON_SMP
269 This is a driver for the Specialix IO8+ multiport card (both the
270 ISA and the PCI version) which gives you many serial ports. You
271 would need something like this to connect more than two modems to
272 your Linux box, for instance in order to become a dial-in server.
274 If you have a card like that, say Y here and read the file
275 <file:Documentation/specialix.txt>. Also it's possible to say M here
276 and compile this driver as kernel loadable module which will be
279 config SPECIALIX_RTSCTS
280 bool "Specialix DTR/RTS pin is RTS"
283 The Specialix IO8+ card can only support either RTS or DTR. If you
284 say N here, the driver will use the pin as "DTR" when the tty is in
285 software handshake mode. If you say Y here or hardware handshake is
286 on, it will always be RTS. Read the file
287 <file:Documentation/specialix.txt> for more information.
290 tristate "Specialix SX (and SI) card support"
291 depends on SERIAL_NONSTANDARD && BROKEN_ON_SMP
293 This is a driver for the SX and SI multiport serial cards.
294 Please read the file <file:Documentation/sx.txt> for details.
296 This driver can only be built as a module ( = code which can be
297 inserted in and removed from the running kernel whenever you want).
298 The module will be called sx. If you want to do that, say M here.
301 tristate "Specialix RIO system support"
302 depends on SERIAL_NONSTANDARD && BROKEN_ON_SMP
304 This is a driver for the Specialix RIO, a smart serial card which
305 drives an outboard box that can support up to 128 ports. Product
306 information is at <http://www.perle.com/support/documentation.html#multiport>.
307 There are both ISA and PCI versions.
310 bool "Support really old RIO/PCI cards"
313 Older RIO PCI cards need some initialization-time configuration to
314 determine the IRQ and some control addresses. If you have a RIO and
315 this doesn't seem to work, try setting this to Y.
318 bool "Stallion multiport serial support"
319 depends on SERIAL_NONSTANDARD
321 Stallion cards give you many serial ports. You would need something
322 like this to connect more than two modems to your Linux box, for
323 instance in order to become a dial-in server. If you say Y here,
324 you will be asked for your specific card model in the next
325 questions. Make sure to read <file:Documentation/stallion.txt> in
326 this case. If you have never heard about all this, it's safe to
330 tristate "Stallion EasyIO or EC8/32 support"
331 depends on STALDRV && BROKEN_ON_SMP
333 If you have an EasyIO or EasyConnection 8/32 multiport Stallion
334 card, then this is for you; say Y. Make sure to read
335 <file:Documentation/stallion.txt>.
337 To compile this driver as a module, choose M here: the
338 module will be called stallion.
341 tristate "Stallion EC8/64, ONboard, Brumby support"
342 depends on STALDRV && BROKEN_ON_SMP
344 If you have an EasyConnection 8/64, ONboard, Brumby or Stallion
345 serial multiport card, say Y here. Make sure to read
346 <file:Documentation/stallion.txt>.
348 To compile this driver as a module, choose M here: the
349 module will be called istallion.
352 bool "TX3912/PR31700 serial port support"
353 depends on SERIAL_NONSTANDARD && MIPS && BROKEN_ON_SMP
355 The TX3912 is a Toshiba RISC processor based o the MIPS 3900 core;
356 see <http://www.toshiba.com/taec/components/Generic/risc/tx3912.htm>.
357 Say Y here to enable kernel support for the on-board serial port.
359 config SERIAL_TX3912_CONSOLE
360 bool "Console on TX3912/PR31700 serial port"
361 depends on SERIAL_TX3912
363 The TX3912 is a Toshiba RISC processor based o the MIPS 3900 core;
364 see <http://www.toshiba.com/taec/components/Generic/risc/tx3912.htm>.
365 Say Y here to direct console I/O to the on-board serial port.
368 bool "Enable Au1000 UART Support"
369 depends on SERIAL_NONSTANDARD && MIPS
371 If you have an Alchemy AU1000 processor (MIPS based) and you want
372 to use serial ports, say Y. Otherwise, say N.
374 config AU1000_SERIAL_CONSOLE
375 bool "Enable Au1000 serial console"
376 depends on AU1000_UART
378 If you have an Alchemy AU1000 processor (MIPS based) and you want
379 to use a console on a serial port, say Y. Otherwise, say N.
381 config QTRONIX_KEYBOARD
382 bool "Enable Qtronix 990P Keyboard Support"
385 Images of Qtronix keyboards are at
386 <http://www.qtronix.com/keyboard.html>.
390 depends on QTRONIX_KEYBOARD
394 bool "Enable Smart Card Reader 0 Support "
397 Say Y here to support smart-card reader 0 (SCR0) on the Integrated
398 Technology Express, Inc. ITE8172 SBC. Vendor page at
399 <http://www.ite.com.tw/ia/brief_it8172bsp.htm>; picture of the
400 board at <http://www.mvista.com/partners/semiconductor/ite.html>.
403 bool "Enable Smart Card Reader 1 Support "
406 Say Y here to support smart-card reader 1 (SCR1) on the Integrated
407 Technology Express, Inc. ITE8172 SBC. Vendor page at
408 <http://www.ite.com.tw/ia/brief_it8172bsp.htm>; picture of the
409 board at <http://www.mvista.com/partners/semiconductor/ite.html>.
412 tristate "Commodore A2232 serial support (EXPERIMENTAL)"
413 depends on EXPERIMENTAL && ZORRO && BROKEN_ON_SMP
415 This option supports the 2232 7-port serial card shipped with the
416 Amiga 2000 and other Zorro-bus machines, dating from 1989. At
417 a max of 19,200 bps, the ports are served by a 6551 ACIA UART chip
418 each, plus a 8520 CIA, and a master 6502 CPU and buffer as well. The
419 ports were connected with 8 pin DIN connectors on the card bracket,
420 for which 8 pin to DB25 adapters were supplied. The card also had
421 jumpers internally to toggle various pinning configurations.
423 This driver can be built as a module; but then "generic_serial"
424 will also be built as a module. This has to be loaded before
425 "ser_a2232". If you want to do this, answer M here.
427 source "drivers/serial/Kconfig"
430 bool "Unix98 PTY support" if EMBEDDED
433 A pseudo terminal (PTY) is a software device consisting of two
434 halves: a master and a slave. The slave device behaves identical to
435 a physical terminal; the master device is used by a process to
436 read data from and write data to the slave, thereby emulating a
437 terminal. Typical programs for the master side are telnet servers
440 Linux has traditionally used the BSD-like names /dev/ptyxx for
441 masters and /dev/ttyxx for slaves of pseudo terminals. This scheme
442 has a number of problems. The GNU C library glibc 2.1 and later,
443 however, supports the Unix98 naming standard: in order to acquire a
444 pseudo terminal, a process opens /dev/ptmx; the number of the pseudo
445 terminal is then made available to the process and the pseudo
446 terminal slave can be accessed as /dev/pts/<number>. What was
447 traditionally /dev/ttyp2 will then be /dev/pts/2, for example.
449 All modern Linux systems use the Unix98 ptys. Say Y unless
450 you're on an embedded system and want to conserve memory.
453 bool "Legacy (BSD) PTY support"
456 A pseudo terminal (PTY) is a software device consisting of two
457 halves: a master and a slave. The slave device behaves identical to
458 a physical terminal; the master device is used by a process to
459 read data from and write data to the slave, thereby emulating a
460 terminal. Typical programs for the master side are telnet servers
463 Linux has traditionally used the BSD-like names /dev/ptyxx
464 for masters and /dev/ttyxx for slaves of pseudo
465 terminals. This scheme has a number of problems, including
466 security. This option enables these legacy devices; on most
467 systems, it is safe to say N.
470 config LEGACY_PTY_COUNT
471 int "Maximum number of legacy PTY in use"
472 depends on LEGACY_PTYS
475 The maximum number of legacy PTYs that can be used at any one time.
476 The default is 256, and should be more than enough. Embedded
477 systems may want to reduce this to save memory.
479 When not in use, each legacy PTY occupies 12 bytes on 32-bit
480 architectures and 24 bytes on 64-bit architectures.
483 tristate "Parallel printer support"
486 If you intend to attach a printer to the parallel port of your Linux
487 box (as opposed to using a serial printer; if the connector at the
488 printer has 9 or 25 holes ["female"], then it's serial), say Y.
489 Also read the Printing-HOWTO, available from
490 <http://www.tldp.org/docs.html#howto>.
492 It is possible to share one parallel port among several devices
493 (e.g. printer and ZIP drive) and it is safe to compile the
494 corresponding drivers into the kernel.
496 To compile this driver as a module, choose M here and read
497 <file:Documentation/parport.txt>. The module will be called lp.
499 If you have several parallel ports, you can specify which ports to
500 use with the "lp" kernel command line option. (Try "man bootparam"
501 or see the documentation of your boot loader (lilo or loadlin) about
502 how to pass options to the kernel at boot time.) The syntax of the
503 "lp" command line option can be found in <file:drivers/char/lp.c>.
505 If you have more than 8 printers, you need to increase the LP_NO
506 macro in lp.c and the PARPORT_MAX macro in parport.h.
509 bool "Support for console on line printer"
512 If you want kernel messages to be printed out as they occur, you
513 can have a console on the printer. This option adds support for
514 doing that; to actually get it to happen you need to pass the
515 option "console=lp0" to the kernel at boot time.
517 If the printer is out of paper (or off, or unplugged, or too
518 busy..) the kernel will stall until the printer is ready again.
519 By defining CONSOLE_LP_STRICT to 0 (at your own risk) you
520 can make the kernel continue when this happens,
521 but it'll lose the kernel messages.
526 tristate "Support for user-space parallel port device drivers"
529 Saying Y to this adds support for /dev/parport device nodes. This
530 is needed for programs that want portable access to the parallel
531 port, for instance deviceid (which displays Plug-and-Play device
534 This is the parallel port equivalent of SCSI generic support (sg).
535 It is safe to say N to this -- it is not needed for normal printing
536 or parallel port CD-ROM/disk support.
538 To compile this driver as a module, choose M here: the
539 module will be called ppdev.
544 tristate "Texas Instruments parallel link cable support"
547 If you own a Texas Instruments graphing calculator and use a
548 parallel link cable, then you might be interested in this driver.
550 If you enable this driver, you will be able to communicate with
551 your calculator through a set of device nodes under /dev. The
552 main advantage of this driver is that you don't have to be root
553 to use this precise link cable (depending on the permissions on
554 the device nodes, though).
556 To compile this driver as a module, choose M here: the
557 module will be called tipar.
559 If you don't know what a parallel link cable is or what a Texas
560 Instruments graphing calculator is, then you probably don't need this
566 bool "pSeries Hypervisor Virtual Console support"
567 depends on PPC_PSERIES
569 pSeries machines when partitioned support a hypervisor virtual
570 console. This driver allows each pSeries partition to have a console
571 which is accessed via the HMC.
574 tristate "IBM Hypervisor Virtual Console Server support"
575 depends on PPC_PSERIES
577 Partitionable IBM Power5 ppc64 machines allow hosting of
578 firmware virtual consoles from one Linux partition by
579 another Linux partition. This driver allows console data
580 from Linux partitions to be accessed through TTY device
581 interfaces in the device tree of a Linux partition running
584 To compile this driver as a module, choose M here: the
585 module will be called hvcs.ko. Additionally, this module
586 will depend on arch specific APIs exported from hvcserver.ko
587 which will also be compiled when this driver is built as a
591 tristate "QIC-02 tape support"
593 If you have a non-SCSI tape drive like that, say Y.
595 To compile this driver as a module, choose M here: the
596 module will be called tpqic02.
599 bool "Do you want runtime configuration for QIC-02"
600 depends on QIC02_TAPE
602 You can either configure this driver once and for all by editing a
603 header file (<file:include/linux/tpqic02.h>), in which case you
604 should say N, or you can fetch a program via anonymous FTP which is
605 able to configure this driver during runtime. The program to do
606 this is called 'qic02conf' and it is part of the
607 tpqic02-support-X.Y.tar.gz support package.
609 If you want to use the qic02conf program, say Y.
611 comment "Edit configuration parameters in ./include/linux/tpqic02.h!"
612 depends on QIC02_TAPE && !QIC02_DYNCONF
614 comment "Setting runtime QIC-02 configuration is done with qic02conf"
615 depends on QIC02_TAPE && QIC02_DYNCONF
617 comment "from the tpqic02-support package. It is available at"
618 depends on QIC02_TAPE && QIC02_DYNCONF
620 comment "metalab.unc.edu or ftp://titus.cfw.com/pub/Linux/util/"
621 depends on QIC02_TAPE && QIC02_DYNCONF
623 source "drivers/char/ipmi/Kconfig"
625 source "drivers/char/watchdog/Kconfig"
628 tristate "NetWinder thermometer support"
629 depends on ARCH_NETWINDER
631 Say Y here to include support for the thermal management hardware
632 found in the NetWinder. This driver allows the user to control the
633 temperature set points and to read the current temperature.
635 It is also possible to say M here to build it as a module (ds1620)
636 It is recommended to be used on a NetWinder, but it is not a
640 tristate "NetWinder Button"
641 depends on ARCH_NETWINDER
643 If you say Y here and create a character device node /dev/nwbutton
644 with major and minor numbers 10 and 158 ("man mknod"), then every
645 time the orange button is pressed a number of times, the number of
646 times the button was pressed will be written to that device.
648 This is most useful for applications, as yet unwritten, which
649 perform actions based on how many times the button is pressed in a
652 Do not hold the button down for too long, as the driver does not
653 alter the behaviour of the hardware reset circuitry attached to the
654 button; it will still execute a hard reset if the button is held
655 down for longer than approximately five seconds.
657 To compile this driver as a module, choose M here: the
658 module will be called nwbutton.
660 Most people will answer Y to this question and "Reboot Using Button"
661 below to be able to initiate a system shutdown from the button.
663 config NWBUTTON_REBOOT
664 bool "Reboot Using Button"
667 If you say Y here, then you will be able to initiate a system
668 shutdown and reboot by pressing the orange button a number of times.
669 The number of presses to initiate the shutdown is two by default,
670 but this can be altered by modifying the value of NUM_PRESSES_REBOOT
671 in nwbutton.h and recompiling the driver or, if you compile the
672 driver as a module, you can specify the number of presses at load
673 time with "insmod button reboot_count=<something>".
676 tristate "NetWinder flash support"
677 depends on ARCH_NETWINDER
679 If you say Y here and create a character device /dev/flash with
680 major 10 and minor 160 you can manipulate the flash ROM containing
681 the NetWinder firmware. Be careful as accidentally overwriting the
682 flash contents can render your computer unbootable. On no account
683 allow random users access to this device. :-)
685 To compile this driver as a module, choose M here: the
686 module will be called nwflash.
688 If you're not sure, say N.
691 tristate "Intel/AMD/VIA HW Random Number Generator support"
692 depends on (X86 || IA64) && PCI
694 This driver provides kernel-side support for the Random Number
695 Generator hardware found on Intel i8xx-based motherboards,
696 AMD 76x-based motherboards, and Via Nehemiah CPUs.
698 Provides a character driver, used to read() entropy data.
700 To compile this driver as a module, choose M here: the
701 module will be called hw_random.
706 tristate "/dev/nvram support"
707 depends on ATARI || X86 || X86_64 || ARM || GENERIC_NVRAM
709 If you say Y here and create a character special file /dev/nvram
710 with major number 10 and minor number 144 using mknod ("man mknod"),
711 you get read and write access to the extra bytes of non-volatile
712 memory in the real time clock (RTC), which is contained in every PC
713 and most Ataris. The actual number of bytes varies, depending on the
714 nvram in the system, but is usually 114 (128-14 for the RTC).
716 This memory is conventionally called "CMOS RAM" on PCs and "NVRAM"
717 on Ataris. /dev/nvram may be used to view settings there, or to
718 change them (with some utility). It could also be used to frequently
719 save a few bits of very important data that may not be lost over
720 power-off and for which writing to disk is too insecure. Note
721 however that most NVRAM space in a PC belongs to the BIOS and you
722 should NEVER idly tamper with it. See Ralf Brown's interrupt list
723 for a guide to the use of CMOS bytes by your BIOS.
725 On Atari machines, /dev/nvram is always configured and does not need
728 To compile this driver as a module, choose M here: the
729 module will be called nvram.
732 tristate "Enhanced Real Time Clock Support"
733 depends on !PPC32 && !PARISC && !IA64 && !M68K
735 If you say Y here and create a character special file /dev/rtc with
736 major number 10 and minor number 135 using mknod ("man mknod"), you
737 will get access to the real time clock (or hardware clock) built
740 Every PC has such a clock built in. It can be used to generate
741 signals from as low as 1Hz up to 8192Hz, and can also be used
742 as a 24 hour alarm. It reports status information via the file
743 /proc/driver/rtc and its behaviour is set by various ioctls on
746 If you run Linux on a multiprocessor machine and said Y to
747 "Symmetric Multi Processing" above, you should say Y here to read
748 and set the RTC in an SMP compatible fashion.
750 If you think you have a use for such a device (such as periodic data
751 sampling), then say Y here, and read <file:Documentation/rtc.txt>
754 To compile this driver as a module, choose M here: the
755 module will be called rtc.
758 tristate "SGI DS1286 RTC support"
761 If you say Y here and create a character special file /dev/rtc with
762 major number 10 and minor number 135 using mknod ("man mknod"), you
763 will get access to the real time clock built into your computer.
764 Every SGI has such a clock built in. It reports status information
765 via the file /proc/rtc and its behaviour is set by various ioctls on
769 bool "SGI M48T35 RTC support"
772 If you say Y here and create a character special file /dev/rtc with
773 major number 10 and minor number 135 using mknod ("man mknod"), you
774 will get access to the real time clock built into your computer.
775 Every SGI has such a clock built in. It reports status information
776 via the file /proc/rtc and its behaviour is set by various ioctls on
780 tristate "Generic /dev/rtc emulation"
781 depends on RTC!=y && !IA64
783 If you say Y here and create a character special file /dev/rtc with
784 major number 10 and minor number 135 using mknod ("man mknod"), you
785 will get access to the real time clock (or hardware clock) built
788 It reports status information via the file /proc/driver/rtc and its
789 behaviour is set by various ioctls on /dev/rtc. If you enable the
790 "extended RTC operation" below it will also provide an emulation
791 for RTC_UIE which is required by some programs and may improve
792 precision in some cases.
794 To compile this driver as a module, choose M here: the
795 module will be called genrtc.
798 bool "Extended RTC operation"
801 Provides an emulation for RTC_UIE which is required by some programs
802 and may improve precision of the generic RTC support in some cases.
805 bool "EFI Real Time Clock Services"
809 bool "Support for Cobalt LCD"
810 depends on MIPS_COBALT
812 This option enables support for the LCD display and buttons found
813 on Cobalt systems through a misc device.
816 tristate "Double Talk PC internal speech card support"
818 This driver is for the DoubleTalk PC, a speech synthesizer
819 manufactured by RC Systems (<http://www.rcsys.com/>). It is also
820 called the `internal DoubleTalk'.
822 To compile this driver as a module, choose M here: the
823 module will be called dtlk.
826 tristate "Siemens R3964 line discipline"
828 This driver allows synchronous communication with devices using the
829 Siemens R3964 packet protocol. Unless you are dealing with special
830 hardware like PLCs, you are unlikely to need this.
832 To compile this driver as a module, choose M here: the
833 module will be called n_r3964.
838 tristate "Applicom intelligent fieldbus card support"
841 This driver provides the kernel-side support for the intelligent
842 fieldbus cards made by Applicom International. More information
843 about these cards can be found on the WWW at the address
844 <http://www.applicom-int.com/>, or by email from David Woodhouse
845 <dwmw2@infradead.org>.
847 To compile this driver as a module, choose M here: the
848 module will be called applicom.
853 tristate "Sony Vaio Programmable I/O Control Device support (EXPERIMENTAL)"
854 depends on EXPERIMENTAL && X86 && PCI && !64BIT
856 This driver enables access to the Sony Programmable I/O Control
857 Device which can be found in many (all ?) Sony Vaio laptops.
859 If you have one of those laptops, read
860 <file:Documentation/sonypi.txt>, and say Y or M here.
862 To compile this driver as a module, choose M here: the
863 module will be called sonypi.
866 menu "Ftape, the floppy tape device driver"
869 tristate "Ftape (QIC-80/Travan) support"
870 depends on BROKEN_ON_SMP && (ALPHA || X86)
872 If you have a tape drive that is connected to your floppy
873 controller, say Y here.
875 Some tape drives (like the Seagate "Tape Store 3200" or the Iomega
876 "Ditto 3200" or the Exabyte "Eagle TR-3") come with a "high speed"
877 controller of their own. These drives (and their companion
878 controllers) are also supported if you say Y here.
880 If you have a special controller (such as the CMS FC-10, FC-20,
881 Mountain Mach-II, or any controller that is based on the Intel 82078
882 FDC like the high speed controllers by Seagate and Exabyte and
883 Iomega's "Ditto Dash") you must configure it by selecting the
884 appropriate entries from the "Floppy tape controllers" sub-menu
885 below and possibly modify the default values for the IRQ and DMA
886 channel and the IO base in ftape's configuration menu.
888 If you want to use your floppy tape drive on a PCI-bus based system,
889 please read the file <file:drivers/char/ftape/README.PCI>.
891 The ftape kernel driver is also available as a runtime loadable
892 module. To compile this driver as a module, choose M here: the
893 module will be called ftape.
895 Note that the Ftape-HOWTO is out of date (sorry) and documents the
896 older version 2.08 of this software but still contains useful
897 information. There is a web page with more recent documentation at
898 <http://www.instmath.rwth-aachen.de/~heine/ftape/>. This page
899 always contains the latest release of the ftape driver and useful
900 information (backup software, ftape related patches and
901 documentation, FAQ). Note that the file system interface has
902 changed quite a bit compared to previous versions of ftape. Please
903 read <file:Documentation/ftape.txt>.
905 source "drivers/char/ftape/Kconfig"
909 source "drivers/char/agp/Kconfig"
911 source "drivers/char/drm/Kconfig"
913 source "drivers/char/pcmcia/Kconfig"
916 tristate "ACP Modem (Mwave) support"
920 The ACP modem (Mwave) for Linux is a WinModem. It is composed of a
921 kernel driver and a user level application. Together these components
922 support direct attachment to public switched telephone networks (PSTNs)
923 and support selected world wide countries.
925 This version of the ACP Modem driver supports the IBM Thinkpad 600E,
926 600, and 770 that include on board ACP modem hardware.
928 The modem also supports the standard communications port interface
929 (ttySx) and is compatible with the Hayes AT Command Set.
931 The user level application needed to use this driver can be found at
932 the IBM Linux Technology Center (LTC) web site:
933 <http://www.ibm.com/linux/ltc/>.
935 If you own one of the above IBM Thinkpads which has the Mwave chipset
938 To compile this driver as a module, choose M here: the
939 module will be called mwave.
942 tristate "NatSemi SCx200 GPIO Support"
945 Give userspace access to the GPIO pins on the National
946 Semiconductor SCx200 processors.
948 If compiled as a module, it will be called scx200_gpio.
951 tristate "RAW driver (/dev/raw/rawN) (OBSOLETE)"
953 The raw driver permits block devices to be bound to /dev/raw/rawN.
954 Once bound, I/O against /dev/raw/rawN uses efficient zero-copy I/O.
955 See the raw(8) manpage for more details.
957 The raw driver is deprecated and may be removed from 2.7
958 kernels. Applications should simply open the device (eg /dev/hda1)
959 with the O_DIRECT flag.
962 bool "HPET - High Precision Event Timer" if (X86 || IA64)
966 If you say Y here, you will have a miscdevice named "/dev/hpet/". Each
967 open selects one of the timers supported by the HPET. The timers are
968 non-periodioc and/or periodic.
971 bool "HPET Control RTC IRQ" if !HPET_EMULATE_RTC
975 If you say Y here, you will disable RTC_IRQ in drivers/char/rtc.c. It
976 is assumed the platform called hpet_alloc with the RTC IRQ values for
980 bool "Allow mmap of HPET"
984 If you say Y here, user applications will be able to mmap
987 In some hardware implementations, the page containing HPET
988 registers may also contain other things that shouldn't be
989 exposed to the user. If this applies to your hardware,
993 int "Maximum number of RAW devices to support (1-8192)"
994 depends on RAW_DRIVER
997 The maximum number of RAW devices that are supported.
998 Default is 256. Increase this number in case you need lots of
1001 config HANGCHECK_TIMER
1002 tristate "Hangcheck timer"
1003 depends on X86_64 || X86
1005 The hangcheck-timer module detects when the system has gone
1006 out to lunch past a certain margin. It can reboot the system
1007 or merely print a warning.