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 source "drivers/char/ipmi/Kconfig"
184 tristate "NetWinder thermometer support"
185 depends on ARCH_NETWINDER
187 Say Y here to include support for the thermal management hardware
188 found in the NetWinder. This driver allows the user to control the
189 temperature set points and to read the current temperature.
191 It is also possible to say M here to build it as a module (ds1620)
192 It is recommended to be used on a NetWinder, but it is not a
196 tristate "NetWinder Button"
197 depends on ARCH_NETWINDER
199 If you say Y here and create a character device node /dev/nwbutton
200 with major and minor numbers 10 and 158 ("man mknod"), then every
201 time the orange button is pressed a number of times, the number of
202 times the button was pressed will be written to that device.
204 This is most useful for applications, as yet unwritten, which
205 perform actions based on how many times the button is pressed in a
208 Do not hold the button down for too long, as the driver does not
209 alter the behaviour of the hardware reset circuitry attached to the
210 button; it will still execute a hard reset if the button is held
211 down for longer than approximately five seconds.
213 To compile this driver as a module, choose M here: the
214 module will be called nwbutton.
216 Most people will answer Y to this question and "Reboot Using Button"
217 below to be able to initiate a system shutdown from the button.
219 config NWBUTTON_REBOOT
220 bool "Reboot Using Button"
223 If you say Y here, then you will be able to initiate a system
224 shutdown and reboot by pressing the orange button a number of times.
225 The number of presses to initiate the shutdown is two by default,
226 but this can be altered by modifying the value of NUM_PRESSES_REBOOT
227 in nwbutton.h and recompiling the driver or, if you compile the
228 driver as a module, you can specify the number of presses at load
229 time with "insmod button reboot_count=<something>".
232 tristate "NetWinder flash support"
233 depends on ARCH_NETWINDER
235 If you say Y here and create a character device /dev/flash with
236 major 10 and minor 160 you can manipulate the flash ROM containing
237 the NetWinder firmware. Be careful as accidentally overwriting the
238 flash contents can render your computer unbootable. On no account
239 allow random users access to this device. :-)
241 To compile this driver as a module, choose M here: the
242 module will be called nwflash.
244 If you're not sure, say N.
246 source "drivers/char/hw_random/Kconfig"
249 tristate "/dev/nvram support"
250 depends on ATARI || X86 || (ARM && RTC_DRV_CMOS) || GENERIC_NVRAM
252 If you say Y here and create a character special file /dev/nvram
253 with major number 10 and minor number 144 using mknod ("man mknod"),
254 you get read and write access to the extra bytes of non-volatile
255 memory in the real time clock (RTC), which is contained in every PC
256 and most Ataris. The actual number of bytes varies, depending on the
257 nvram in the system, but is usually 114 (128-14 for the RTC).
259 This memory is conventionally called "CMOS RAM" on PCs and "NVRAM"
260 on Ataris. /dev/nvram may be used to view settings there, or to
261 change them (with some utility). It could also be used to frequently
262 save a few bits of very important data that may not be lost over
263 power-off and for which writing to disk is too insecure. Note
264 however that most NVRAM space in a PC belongs to the BIOS and you
265 should NEVER idly tamper with it. See Ralf Brown's interrupt list
266 for a guide to the use of CMOS bytes by your BIOS.
268 On Atari machines, /dev/nvram is always configured and does not need
271 To compile this driver as a module, choose M here: the
272 module will be called nvram.
275 # These legacy RTC drivers just cause too many conflicts with the generic
276 # RTC framework ... let's not even try to coexist any more.
281 tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
282 depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
283 && !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN && !UML
285 If you say Y here and create a character special file /dev/rtc with
286 major number 10 and minor number 135 using mknod ("man mknod"), you
287 will get access to the real time clock (or hardware clock) built
290 Every PC has such a clock built in. It can be used to generate
291 signals from as low as 1Hz up to 8192Hz, and can also be used
292 as a 24 hour alarm. It reports status information via the file
293 /proc/driver/rtc and its behaviour is set by various ioctls on
296 If you run Linux on a multiprocessor machine and said Y to
297 "Symmetric Multi Processing" above, you should say Y here to read
298 and set the RTC in an SMP compatible fashion.
300 If you think you have a use for such a device (such as periodic data
301 sampling), then say Y here, and read <file:Documentation/rtc.txt>
304 To compile this driver as a module, choose M here: the
305 module will be called rtc.
308 tristate "Enhanced Real Time Clock Support"
309 depends on SPARC32 && PCI
311 If you say Y here and create a character special file /dev/rtc with
312 major number 10 and minor number 135 using mknod ("man mknod"), you
313 will get access to the real time clock (or hardware clock) built
316 Every PC has such a clock built in. It can be used to generate
317 signals from as low as 1Hz up to 8192Hz, and can also be used
318 as a 24 hour alarm. It reports status information via the file
319 /proc/driver/rtc and its behaviour is set by various ioctls on
322 If you think you have a use for such a device (such as periodic data
323 sampling), then say Y here, and read <file:Documentation/rtc.txt>
326 To compile this driver as a module, choose M here: the
327 module will be called js-rtc.
330 tristate "Generic /dev/rtc emulation"
331 depends on RTC!=y && !IA64 && !ARM && !M32R && !MIPS && !SPARC && !FRV && !S390 && !SUPERH && !AVR32 && !BLACKFIN && !UML
333 If you say Y here and create a character special file /dev/rtc with
334 major number 10 and minor number 135 using mknod ("man mknod"), you
335 will get access to the real time clock (or hardware clock) built
338 It reports status information via the file /proc/driver/rtc and its
339 behaviour is set by various ioctls on /dev/rtc. If you enable the
340 "extended RTC operation" below it will also provide an emulation
341 for RTC_UIE which is required by some programs and may improve
342 precision in some cases.
344 To compile this driver as a module, choose M here: the
345 module will be called genrtc.
348 bool "Extended RTC operation"
351 Provides an emulation for RTC_UIE which is required by some programs
352 and may improve precision of the generic RTC support in some cases.
355 bool "EFI Real Time Clock Services"
359 tristate "DS1302 RTC support"
360 depends on M32R && (PLAT_M32700UT || PLAT_OPSPUT)
362 If you say Y here and create a character special file /dev/rtc with
363 major number 121 and minor number 0 using mknod ("man mknod"), you
364 will get access to the real time clock (or hardware clock) built
370 tristate "Double Talk PC internal speech card support"
373 This driver is for the DoubleTalk PC, a speech synthesizer
374 manufactured by RC Systems (<http://www.rcsys.com/>). It is also
375 called the `internal DoubleTalk'.
377 To compile this driver as a module, choose M here: the
378 module will be called dtlk.
381 tristate "Xilinx HWICAP Support"
382 depends on XILINX_VIRTEX || MICROBLAZE
384 This option enables support for Xilinx Internal Configuration
385 Access Port (ICAP) driver. The ICAP is used on Xilinx Virtex
386 FPGA platforms to partially reconfigure the FPGA at runtime.
391 tristate "Siemens R3964 line discipline"
394 This driver allows synchronous communication with devices using the
395 Siemens R3964 packet protocol. Unless you are dealing with special
396 hardware like PLCs, you are unlikely to need this.
398 To compile this driver as a module, choose M here: the
399 module will be called n_r3964.
404 tristate "Applicom intelligent fieldbus card support"
407 This driver provides the kernel-side support for the intelligent
408 fieldbus cards made by Applicom International. More information
409 about these cards can be found on the WWW at the address
410 <http://www.applicom-int.com/>, or by email from David Woodhouse
411 <dwmw2@infradead.org>.
413 To compile this driver as a module, choose M here: the
414 module will be called applicom.
419 tristate "Sony Vaio Programmable I/O Control Device support"
420 depends on X86_32 && PCI && INPUT
422 This driver enables access to the Sony Programmable I/O Control
423 Device which can be found in many (all ?) Sony Vaio laptops.
425 If you have one of those laptops, read
426 <file:Documentation/laptops/sonypi.txt>, and say Y or M here.
428 To compile this driver as a module, choose M here: the
429 module will be called sonypi.
432 tristate "TANBAC TB0219 GPIO support"
433 depends on TANBAC_TB022X
436 source "drivers/char/pcmcia/Kconfig"
439 tristate "ACP Modem (Mwave) support"
440 depends on X86 && TTY
443 The ACP modem (Mwave) for Linux is a WinModem. It is composed of a
444 kernel driver and a user level application. Together these components
445 support direct attachment to public switched telephone networks (PSTNs)
446 and support selected world wide countries.
448 This version of the ACP Modem driver supports the IBM Thinkpad 600E,
449 600, and 770 that include on board ACP modem hardware.
451 The modem also supports the standard communications port interface
452 (ttySx) and is compatible with the Hayes AT Command Set.
454 The user level application needed to use this driver can be found at
455 the IBM Linux Technology Center (LTC) web site:
456 <http://www.ibm.com/linux/ltc/>.
458 If you own one of the above IBM Thinkpads which has the Mwave chipset
461 To compile this driver as a module, choose M here: the
462 module will be called mwave.
465 tristate "NatSemi SCx200 GPIO Support"
469 Give userspace access to the GPIO pins on the National
470 Semiconductor SCx200 processors.
472 If compiled as a module, it will be called scx200_gpio.
475 tristate "NatSemi PC8736x GPIO Support"
476 depends on X86_32 && !UML
477 default SCx200_GPIO # mostly N
478 select NSC_GPIO # needed for support routines
480 Give userspace access to the GPIO pins on the National
481 Semiconductor PC-8736x (x=[03456]) SuperIO chip. The chip
482 has multiple functional units, inc several managed by
483 hwmon/pc87360 driver. Tested with PC-87366
485 If compiled as a module, it will be called pc8736x_gpio.
488 tristate "NatSemi Base GPIO Support"
490 # selected by SCx200_GPIO and PC8736x_GPIO
491 # what about 2 selectors differing: m != y
493 Common support used (and needed) by scx200_gpio and
494 pc8736x_gpio drivers. If those drivers are built as
495 modules, this one will be too, named nsc_gpio
498 tristate "RAW driver (/dev/raw/rawN)"
501 The raw driver permits block devices to be bound to /dev/raw/rawN.
502 Once bound, I/O against /dev/raw/rawN uses efficient zero-copy I/O.
503 See the raw(8) manpage for more details.
505 Applications should preferably open the device (eg /dev/hda1)
506 with the O_DIRECT flag.
509 int "Maximum number of RAW devices to support (1-65536)"
510 depends on RAW_DRIVER
514 The maximum number of RAW devices that are supported.
515 Default is 256. Increase this number in case you need lots of
519 bool "HPET - High Precision Event Timer" if (X86 || IA64)
523 If you say Y here, you will have a miscdevice named "/dev/hpet/". Each
524 open selects one of the timers supported by the HPET. The timers are
525 non-periodic and/or periodic.
528 bool "Allow mmap of HPET"
532 If you say Y here, user applications will be able to mmap
535 config HPET_MMAP_DEFAULT
536 bool "Enable HPET MMAP access by default"
540 In some hardware implementations, the page containing HPET
541 registers may also contain other things that shouldn't be
542 exposed to the user. This option selects the default (if
543 kernel parameter hpet_mmap is not set) user access to the
544 registers for applications that require it.
546 config HANGCHECK_TIMER
547 tristate "Hangcheck timer"
548 depends on X86 || IA64 || PPC64 || S390
550 The hangcheck-timer module detects when the system has gone
551 out to lunch past a certain margin. It can reboot the system
552 or merely print a warning.
555 tristate "MMTIMER Memory mapped RTC for SGI Altix"
556 depends on IA64_GENERIC || IA64_SGI_SN2
559 The mmtimer device allows direct userspace access to the
563 tristate "UV_MMTIMER Memory mapped RTC for SGI UV"
567 The uv_mmtimer device allows direct userspace access to the
570 source "drivers/char/tpm/Kconfig"
573 tristate "Telecom clock driver for ATCA SBC"
577 The telecom clock device is specific to the MPCBL0010 and MPCBL0050
578 ATCA computers and allows direct userspace access to the
579 configuration of the telecom clock configuration settings. This
580 device is used for hardware synchronization across the ATCA backplane
581 fabric. Upon loading, the driver exports a sysfs directory,
582 /sys/devices/platform/telco_clock, with a number of files for
583 controlling the behavior of this hardware.
588 depends on ISA || PCI
591 source "drivers/s390/char/Kconfig"
594 bool "Character-device access via hypervisor to the Tilera SPI ROM"
598 This device provides character-level read-write access
599 to the SROM, typically via the "0", "1", and "2" devices
600 in /dev/srom/. The Tilera hypervisor makes the flash
601 device appear much like a simple EEPROM, and knows
602 how to partition a single ROM for multiple purposes.
604 source "drivers/char/xillybus/Kconfig"