2 # Character device configuration
5 menu "Character devices"
7 source "drivers/tty/Kconfig"
10 bool "/dev/mem virtual device support"
13 Say Y here if you want to support the /dev/mem device.
14 The /dev/mem device is used to access areas of physical
16 When in doubt, say "Y".
19 bool "/dev/kmem virtual device support"
22 Say Y here if you want to support the /dev/kmem device. The
23 /dev/kmem device is rarely used, but can be used for certain
24 kind of kernel debugging operations.
25 When in doubt, say "N".
28 bool "SGI Altix system controller communication support"
29 depends on (IA64_SGI_SN2 || IA64_GENERIC)
31 If you have an SGI Altix and you want to enable system
32 controller communication from user space (you want this!),
33 say Y. Otherwise, say N.
36 bool "SGI TIO CX driver support"
37 depends on (IA64_SGI_SN2 || IA64_GENERIC)
39 If you have an SGI Altix and you have fpga devices attached
40 to your TIO, say Y here, otherwise say N.
43 tristate "SGI FPGA Core Services driver support"
46 If you have an SGI Altix with an attached SABrick
47 say Y or M here, otherwise say N.
49 source "drivers/tty/serial/Kconfig"
52 tristate "TTY driver to output user messages via printk"
53 depends on EXPERT && TTY
56 If you say Y here, the support for writing user messages (i.e.
57 console messages) via printk is available.
59 The feature is useful to inline user messages with kernel
61 In order to use this feature, you should output user messages
62 to /dev/ttyprintk or redirect console to this TTY.
67 tristate "Blackfin On-Chip OTP Memory Support"
68 depends on BLACKFIN && (BF51x || BF52x || BF54x)
71 If you say Y here, you will get support for a character device
72 interface into the One Time Programmable memory pages that are
73 stored on the Blackfin processor. This will not get you access
74 to the secure memory pages however. You will need to write your
75 own secure code and reader for that.
77 To compile this driver as a module, choose M here: the module
78 will be called bfin-otp.
80 If unsure, it is safe to say Y.
82 config BFIN_OTP_WRITE_ENABLE
83 bool "Enable writing support of OTP pages"
87 If you say Y here, you will enable support for writing of the
88 OTP pages. This is dangerous by nature as you can only program
89 the pages once, so only enable this option when you actually
90 need it so as to not inadvertently clobber data.
95 tristate "Parallel printer support"
98 If you intend to attach a printer to the parallel port of your Linux
99 box (as opposed to using a serial printer; if the connector at the
100 printer has 9 or 25 holes ["female"], then it's serial), say Y.
101 Also read the Printing-HOWTO, available from
102 <http://www.tldp.org/docs.html#howto>.
104 It is possible to share one parallel port among several devices
105 (e.g. printer and ZIP drive) and it is safe to compile the
106 corresponding drivers into the kernel.
108 To compile this driver as a module, choose M here and read
109 <file:Documentation/parport.txt>. The module will be called lp.
111 If you have several parallel ports, you can specify which ports to
112 use with the "lp" kernel command line option. (Try "man bootparam"
113 or see the documentation of your boot loader (lilo or loadlin) about
114 how to pass options to the kernel at boot time.) The syntax of the
115 "lp" command line option can be found in <file:drivers/char/lp.c>.
117 If you have more than 8 printers, you need to increase the LP_NO
118 macro in lp.c and the PARPORT_MAX macro in parport.h.
121 bool "Support for console on line printer"
124 If you want kernel messages to be printed out as they occur, you
125 can have a console on the printer. This option adds support for
126 doing that; to actually get it to happen you need to pass the
127 option "console=lp0" to the kernel at boot time.
129 If the printer is out of paper (or off, or unplugged, or too
130 busy..) the kernel will stall until the printer is ready again.
131 By defining CONSOLE_LP_STRICT to 0 (at your own risk) you
132 can make the kernel continue when this happens,
133 but it'll lose the kernel messages.
138 tristate "Support for user-space parallel port device drivers"
141 Saying Y to this adds support for /dev/parport device nodes. This
142 is needed for programs that want portable access to the parallel
143 port, for instance deviceid (which displays Plug-and-Play device
146 This is the parallel port equivalent of SCSI generic support (sg).
147 It is safe to say N to this -- it is not needed for normal printing
148 or parallel port CD-ROM/disk support.
150 To compile this driver as a module, choose M here: the
151 module will be called ppdev.
155 source "drivers/tty/hvc/Kconfig"
157 config VIRTIO_CONSOLE
158 tristate "Virtio console"
159 depends on VIRTIO && TTY
162 Virtio console for use with lguest and other hypervisors.
164 Also serves as a general-purpose serial device for data
165 transfer between the guest and host. Character devices at
166 /dev/vportNpn will be created when corresponding ports are
167 found, where N is the device number and n is the port number
168 within that device. If specified by the host, a sysfs
169 attribute called 'name' will be populated with a name for
170 the port which can be used by udev scripts to create a
171 symlink to the device.
174 tristate "IBM POWER Barrier Synchronization Register support"
175 depends on PPC_PSERIES
177 This devices exposes a hardware mechanism for fast synchronization
178 of threads across a large system which avoids bouncing a cacheline
179 between several cores on a system
181 config POWERNV_OP_PANEL
182 tristate "IBM POWERNV Operator Panel Display support"
183 depends on PPC_POWERNV
186 If you say Y here, a special character device node, /dev/op_panel,
187 will be created which exposes the operator panel display on IBM
188 Power Systems machines with FSPs.
190 If you don't require access to the operator panel display from user
193 If unsure, say M here to build it as a module called powernv-op-panel.
195 source "drivers/char/ipmi/Kconfig"
198 tristate "NetWinder thermometer support"
199 depends on ARCH_NETWINDER
201 Say Y here to include support for the thermal management hardware
202 found in the NetWinder. This driver allows the user to control the
203 temperature set points and to read the current temperature.
205 It is also possible to say M here to build it as a module (ds1620)
206 It is recommended to be used on a NetWinder, but it is not a
210 tristate "NetWinder Button"
211 depends on ARCH_NETWINDER
213 If you say Y here and create a character device node /dev/nwbutton
214 with major and minor numbers 10 and 158 ("man mknod"), then every
215 time the orange button is pressed a number of times, the number of
216 times the button was pressed will be written to that device.
218 This is most useful for applications, as yet unwritten, which
219 perform actions based on how many times the button is pressed in a
222 Do not hold the button down for too long, as the driver does not
223 alter the behaviour of the hardware reset circuitry attached to the
224 button; it will still execute a hard reset if the button is held
225 down for longer than approximately five seconds.
227 To compile this driver as a module, choose M here: the
228 module will be called nwbutton.
230 Most people will answer Y to this question and "Reboot Using Button"
231 below to be able to initiate a system shutdown from the button.
233 config NWBUTTON_REBOOT
234 bool "Reboot Using Button"
237 If you say Y here, then you will be able to initiate a system
238 shutdown and reboot by pressing the orange button a number of times.
239 The number of presses to initiate the shutdown is two by default,
240 but this can be altered by modifying the value of NUM_PRESSES_REBOOT
241 in nwbutton.h and recompiling the driver or, if you compile the
242 driver as a module, you can specify the number of presses at load
243 time with "insmod button reboot_count=<something>".
246 tristate "NetWinder flash support"
247 depends on ARCH_NETWINDER
249 If you say Y here and create a character device /dev/flash with
250 major 10 and minor 160 you can manipulate the flash ROM containing
251 the NetWinder firmware. Be careful as accidentally overwriting the
252 flash contents can render your computer unbootable. On no account
253 allow random users access to this device. :-)
255 To compile this driver as a module, choose M here: the
256 module will be called nwflash.
258 If you're not sure, say N.
260 source "drivers/char/hw_random/Kconfig"
263 tristate "/dev/nvram support"
264 depends on ATARI || X86 || (ARM && RTC_DRV_CMOS) || GENERIC_NVRAM
266 If you say Y here and create a character special file /dev/nvram
267 with major number 10 and minor number 144 using mknod ("man mknod"),
268 you get read and write access to the extra bytes of non-volatile
269 memory in the real time clock (RTC), which is contained in every PC
270 and most Ataris. The actual number of bytes varies, depending on the
271 nvram in the system, but is usually 114 (128-14 for the RTC).
273 This memory is conventionally called "CMOS RAM" on PCs and "NVRAM"
274 on Ataris. /dev/nvram may be used to view settings there, or to
275 change them (with some utility). It could also be used to frequently
276 save a few bits of very important data that may not be lost over
277 power-off and for which writing to disk is too insecure. Note
278 however that most NVRAM space in a PC belongs to the BIOS and you
279 should NEVER idly tamper with it. See Ralf Brown's interrupt list
280 for a guide to the use of CMOS bytes by your BIOS.
282 On Atari machines, /dev/nvram is always configured and does not need
285 To compile this driver as a module, choose M here: the
286 module will be called nvram.
289 # These legacy RTC drivers just cause too many conflicts with the generic
290 # RTC framework ... let's not even try to coexist any more.
295 tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
296 depends on ALPHA || (MIPS && MACH_LOONGSON64) || MN10300
298 If you say Y here and create a character special file /dev/rtc with
299 major number 10 and minor number 135 using mknod ("man mknod"), you
300 will get access to the real time clock (or hardware clock) built
303 Every PC has such a clock built in. It can be used to generate
304 signals from as low as 1Hz up to 8192Hz, and can also be used
305 as a 24 hour alarm. It reports status information via the file
306 /proc/driver/rtc and its behaviour is set by various ioctls on
309 If you run Linux on a multiprocessor machine and said Y to
310 "Symmetric Multi Processing" above, you should say Y here to read
311 and set the RTC in an SMP compatible fashion.
313 If you think you have a use for such a device (such as periodic data
314 sampling), then say Y here, and read <file:Documentation/rtc.txt>
317 To compile this driver as a module, choose M here: the
318 module will be called rtc.
321 tristate "Enhanced Real Time Clock Support"
322 depends on SPARC32 && PCI
324 If you say Y here and create a character special file /dev/rtc with
325 major number 10 and minor number 135 using mknod ("man mknod"), you
326 will get access to the real time clock (or hardware clock) built
329 Every PC has such a clock built in. It can be used to generate
330 signals from as low as 1Hz up to 8192Hz, and can also be used
331 as a 24 hour alarm. It reports status information via the file
332 /proc/driver/rtc and its behaviour is set by various ioctls on
335 If you think you have a use for such a device (such as periodic data
336 sampling), then say Y here, and read <file:Documentation/rtc.txt>
339 To compile this driver as a module, choose M here: the
340 module will be called js-rtc.
343 tristate "Generic /dev/rtc emulation"
345 depends on ALPHA || M68K || MN10300 || PARISC || PPC || X86
347 If you say Y here and create a character special file /dev/rtc with
348 major number 10 and minor number 135 using mknod ("man mknod"), you
349 will get access to the real time clock (or hardware clock) built
352 It reports status information via the file /proc/driver/rtc and its
353 behaviour is set by various ioctls on /dev/rtc. If you enable the
354 "extended RTC operation" below it will also provide an emulation
355 for RTC_UIE which is required by some programs and may improve
356 precision in some cases.
358 To compile this driver as a module, choose M here: the
359 module will be called genrtc.
362 bool "Extended RTC operation"
365 Provides an emulation for RTC_UIE which is required by some programs
366 and may improve precision of the generic RTC support in some cases.
369 bool "EFI Real Time Clock Services"
373 tristate "DS1302 RTC support"
374 depends on M32R && (PLAT_M32700UT || PLAT_OPSPUT)
376 If you say Y here and create a character special file /dev/rtc with
377 major number 121 and minor number 0 using mknod ("man mknod"), you
378 will get access to the real time clock (or hardware clock) built
384 tristate "Double Talk PC internal speech card support"
387 This driver is for the DoubleTalk PC, a speech synthesizer
388 manufactured by RC Systems (<http://www.rcsys.com/>). It is also
389 called the `internal DoubleTalk'.
391 To compile this driver as a module, choose M here: the
392 module will be called dtlk.
395 tristate "Xilinx HWICAP Support"
396 depends on XILINX_VIRTEX || MICROBLAZE
398 This option enables support for Xilinx Internal Configuration
399 Access Port (ICAP) driver. The ICAP is used on Xilinx Virtex
400 FPGA platforms to partially reconfigure the FPGA at runtime.
405 tristate "Siemens R3964 line discipline"
408 This driver allows synchronous communication with devices using the
409 Siemens R3964 packet protocol. Unless you are dealing with special
410 hardware like PLCs, you are unlikely to need this.
412 To compile this driver as a module, choose M here: the
413 module will be called n_r3964.
418 tristate "Applicom intelligent fieldbus card support"
421 This driver provides the kernel-side support for the intelligent
422 fieldbus cards made by Applicom International. More information
423 about these cards can be found on the WWW at the address
424 <http://www.applicom-int.com/>, or by email from David Woodhouse
425 <dwmw2@infradead.org>.
427 To compile this driver as a module, choose M here: the
428 module will be called applicom.
433 tristate "Sony Vaio Programmable I/O Control Device support"
434 depends on X86_32 && PCI && INPUT
436 This driver enables access to the Sony Programmable I/O Control
437 Device which can be found in many (all ?) Sony Vaio laptops.
439 If you have one of those laptops, read
440 <file:Documentation/laptops/sonypi.txt>, and say Y or M here.
442 To compile this driver as a module, choose M here: the
443 module will be called sonypi.
446 tristate "TANBAC TB0219 GPIO support"
447 depends on TANBAC_TB022X
450 source "drivers/char/pcmcia/Kconfig"
453 tristate "ACP Modem (Mwave) support"
454 depends on X86 && TTY
457 The ACP modem (Mwave) for Linux is a WinModem. It is composed of a
458 kernel driver and a user level application. Together these components
459 support direct attachment to public switched telephone networks (PSTNs)
460 and support selected world wide countries.
462 This version of the ACP Modem driver supports the IBM Thinkpad 600E,
463 600, and 770 that include on board ACP modem hardware.
465 The modem also supports the standard communications port interface
466 (ttySx) and is compatible with the Hayes AT Command Set.
468 The user level application needed to use this driver can be found at
469 the IBM Linux Technology Center (LTC) web site:
470 <http://www.ibm.com/linux/ltc/>.
472 If you own one of the above IBM Thinkpads which has the Mwave chipset
475 To compile this driver as a module, choose M here: the
476 module will be called mwave.
479 tristate "NatSemi SCx200 GPIO Support"
483 Give userspace access to the GPIO pins on the National
484 Semiconductor SCx200 processors.
486 If compiled as a module, it will be called scx200_gpio.
489 tristate "NatSemi PC8736x GPIO Support"
490 depends on X86_32 && !UML
491 default SCx200_GPIO # mostly N
492 select NSC_GPIO # needed for support routines
494 Give userspace access to the GPIO pins on the National
495 Semiconductor PC-8736x (x=[03456]) SuperIO chip. The chip
496 has multiple functional units, inc several managed by
497 hwmon/pc87360 driver. Tested with PC-87366
499 If compiled as a module, it will be called pc8736x_gpio.
502 tristate "NatSemi Base GPIO Support"
504 # selected by SCx200_GPIO and PC8736x_GPIO
505 # what about 2 selectors differing: m != y
507 Common support used (and needed) by scx200_gpio and
508 pc8736x_gpio drivers. If those drivers are built as
509 modules, this one will be too, named nsc_gpio
512 tristate "RAW driver (/dev/raw/rawN)"
515 The raw driver permits block devices to be bound to /dev/raw/rawN.
516 Once bound, I/O against /dev/raw/rawN uses efficient zero-copy I/O.
517 See the raw(8) manpage for more details.
519 Applications should preferably open the device (eg /dev/hda1)
520 with the O_DIRECT flag.
523 int "Maximum number of RAW devices to support (1-65536)"
524 depends on RAW_DRIVER
528 The maximum number of RAW devices that are supported.
529 Default is 256. Increase this number in case you need lots of
533 bool "HPET - High Precision Event Timer" if (X86 || IA64)
537 If you say Y here, you will have a miscdevice named "/dev/hpet/". Each
538 open selects one of the timers supported by the HPET. The timers are
539 non-periodic and/or periodic.
542 bool "Allow mmap of HPET"
546 If you say Y here, user applications will be able to mmap
549 config HPET_MMAP_DEFAULT
550 bool "Enable HPET MMAP access by default"
554 In some hardware implementations, the page containing HPET
555 registers may also contain other things that shouldn't be
556 exposed to the user. This option selects the default (if
557 kernel parameter hpet_mmap is not set) user access to the
558 registers for applications that require it.
560 config HANGCHECK_TIMER
561 tristate "Hangcheck timer"
562 depends on X86 || IA64 || PPC64 || S390
564 The hangcheck-timer module detects when the system has gone
565 out to lunch past a certain margin. It can reboot the system
566 or merely print a warning.
569 tristate "MMTIMER Memory mapped RTC for SGI Altix"
570 depends on IA64_GENERIC || IA64_SGI_SN2
573 The mmtimer device allows direct userspace access to the
577 tristate "UV_MMTIMER Memory mapped RTC for SGI UV"
581 The uv_mmtimer device allows direct userspace access to the
584 source "drivers/char/tpm/Kconfig"
587 tristate "Telecom clock driver for ATCA SBC"
591 The telecom clock device is specific to the MPCBL0010 and MPCBL0050
592 ATCA computers and allows direct userspace access to the
593 configuration of the telecom clock configuration settings. This
594 device is used for hardware synchronization across the ATCA backplane
595 fabric. Upon loading, the driver exports a sysfs directory,
596 /sys/devices/platform/telco_clock, with a number of files for
597 controlling the behavior of this hardware.
601 depends on ISA || PCI
604 source "drivers/s390/char/Kconfig"
607 bool "Character-device access via hypervisor to the Tilera SPI ROM"
611 This device provides character-level read-write access
612 to the SROM, typically via the "0", "1", and "2" devices
613 in /dev/srom/. The Tilera hypervisor makes the flash
614 device appear much like a simple EEPROM, and knows
615 how to partition a single ROM for multiple purposes.
617 source "drivers/char/xillybus/Kconfig"