2 # Character device configuration
5 menu "Character devices"
7 source "drivers/tty/Kconfig"
10 bool "/dev/kmem virtual device support"
13 Say Y here if you want to support the /dev/kmem device. The
14 /dev/kmem device is rarely used, but can be used for certain
15 kind of kernel debugging operations.
16 When in doubt, say "N".
19 bool "Stallion multiport serial support"
20 depends on SERIAL_NONSTANDARD
22 Stallion cards give you many serial ports. You would need something
23 like this to connect more than two modems to your Linux box, for
24 instance in order to become a dial-in server. If you say Y here,
25 you will be asked for your specific card model in the next
26 questions. Make sure to read <file:Documentation/serial/stallion.txt>
27 in this case. If you have never heard about all this, it's safe to
31 bool "SGI Altix system controller communication support"
32 depends on (IA64_SGI_SN2 || IA64_GENERIC)
34 If you have an SGI Altix and you want to enable system
35 controller communication from user space (you want this!),
36 say Y. Otherwise, say N.
39 bool "SGI TIO CX driver support"
40 depends on (IA64_SGI_SN2 || IA64_GENERIC)
42 If you have an SGI Altix and you have fpga devices attached
43 to your TIO, say Y here, otherwise say N.
46 tristate "SGI FPGA Core Services driver support"
49 If you have an SGI Altix with an attached SABrick
50 say Y or M here, otherwise say N.
52 source "drivers/tty/serial/Kconfig"
55 bool "TTY driver to output user messages via printk"
59 If you say Y here, the support for writing user messages (i.e.
60 console messages) via printk is available.
62 The feature is useful to inline user messages with kernel
64 In order to use this feature, you should output user messages
65 to /dev/ttyprintk or redirect console to this TTY.
70 tristate "Blackfin On-Chip OTP Memory Support"
71 depends on BLACKFIN && (BF51x || BF52x || BF54x)
74 If you say Y here, you will get support for a character device
75 interface into the One Time Programmable memory pages that are
76 stored on the Blackfin processor. This will not get you access
77 to the secure memory pages however. You will need to write your
78 own secure code and reader for that.
80 To compile this driver as a module, choose M here: the module
81 will be called bfin-otp.
83 If unsure, it is safe to say Y.
85 config BFIN_OTP_WRITE_ENABLE
86 bool "Enable writing support of OTP pages"
90 If you say Y here, you will enable support for writing of the
91 OTP pages. This is dangerous by nature as you can only program
92 the pages once, so only enable this option when you actually
93 need it so as to not inadvertently clobber data.
98 tristate "Parallel printer support"
101 If you intend to attach a printer to the parallel port of your Linux
102 box (as opposed to using a serial printer; if the connector at the
103 printer has 9 or 25 holes ["female"], then it's serial), say Y.
104 Also read the Printing-HOWTO, available from
105 <http://www.tldp.org/docs.html#howto>.
107 It is possible to share one parallel port among several devices
108 (e.g. printer and ZIP drive) and it is safe to compile the
109 corresponding drivers into the kernel.
111 To compile this driver as a module, choose M here and read
112 <file:Documentation/parport.txt>. The module will be called lp.
114 If you have several parallel ports, you can specify which ports to
115 use with the "lp" kernel command line option. (Try "man bootparam"
116 or see the documentation of your boot loader (lilo or loadlin) about
117 how to pass options to the kernel at boot time.) The syntax of the
118 "lp" command line option can be found in <file:drivers/char/lp.c>.
120 If you have more than 8 printers, you need to increase the LP_NO
121 macro in lp.c and the PARPORT_MAX macro in parport.h.
124 bool "Support for console on line printer"
127 If you want kernel messages to be printed out as they occur, you
128 can have a console on the printer. This option adds support for
129 doing that; to actually get it to happen you need to pass the
130 option "console=lp0" to the kernel at boot time.
132 If the printer is out of paper (or off, or unplugged, or too
133 busy..) the kernel will stall until the printer is ready again.
134 By defining CONSOLE_LP_STRICT to 0 (at your own risk) you
135 can make the kernel continue when this happens,
136 but it'll lose the kernel messages.
141 tristate "Support for user-space parallel port device drivers"
144 Saying Y to this adds support for /dev/parport device nodes. This
145 is needed for programs that want portable access to the parallel
146 port, for instance deviceid (which displays Plug-and-Play device
149 This is the parallel port equivalent of SCSI generic support (sg).
150 It is safe to say N to this -- it is not needed for normal printing
151 or parallel port CD-ROM/disk support.
153 To compile this driver as a module, choose M here: the
154 module will be called ppdev.
158 source "drivers/tty/hvc/Kconfig"
160 config VIRTIO_CONSOLE
161 tristate "Virtio console"
165 Virtio console for use with lguest and other hypervisors.
167 Also serves as a general-purpose serial device for data
168 transfer between the guest and host. Character devices at
169 /dev/vportNpn will be created when corresponding ports are
170 found, where N is the device number and n is the port number
171 within that device. If specified by the host, a sysfs
172 attribute called 'name' will be populated with a name for
173 the port which can be used by udev scripts to create a
174 symlink to the device.
177 tristate "IBM POWER Barrier Synchronization Register support"
178 depends on PPC_PSERIES
180 This devices exposes a hardware mechanism for fast synchronization
181 of threads across a large system which avoids bouncing a cacheline
182 between several cores on a system
184 source "drivers/char/ipmi/Kconfig"
187 tristate "NetWinder thermometer support"
188 depends on ARCH_NETWINDER
190 Say Y here to include support for the thermal management hardware
191 found in the NetWinder. This driver allows the user to control the
192 temperature set points and to read the current temperature.
194 It is also possible to say M here to build it as a module (ds1620)
195 It is recommended to be used on a NetWinder, but it is not a
199 tristate "NetWinder Button"
200 depends on ARCH_NETWINDER
202 If you say Y here and create a character device node /dev/nwbutton
203 with major and minor numbers 10 and 158 ("man mknod"), then every
204 time the orange button is pressed a number of times, the number of
205 times the button was pressed will be written to that device.
207 This is most useful for applications, as yet unwritten, which
208 perform actions based on how many times the button is pressed in a
211 Do not hold the button down for too long, as the driver does not
212 alter the behaviour of the hardware reset circuitry attached to the
213 button; it will still execute a hard reset if the button is held
214 down for longer than approximately five seconds.
216 To compile this driver as a module, choose M here: the
217 module will be called nwbutton.
219 Most people will answer Y to this question and "Reboot Using Button"
220 below to be able to initiate a system shutdown from the button.
222 config NWBUTTON_REBOOT
223 bool "Reboot Using Button"
226 If you say Y here, then you will be able to initiate a system
227 shutdown and reboot by pressing the orange button a number of times.
228 The number of presses to initiate the shutdown is two by default,
229 but this can be altered by modifying the value of NUM_PRESSES_REBOOT
230 in nwbutton.h and recompiling the driver or, if you compile the
231 driver as a module, you can specify the number of presses at load
232 time with "insmod button reboot_count=<something>".
235 tristate "NetWinder flash support"
236 depends on ARCH_NETWINDER
238 If you say Y here and create a character device /dev/flash with
239 major 10 and minor 160 you can manipulate the flash ROM containing
240 the NetWinder firmware. Be careful as accidentally overwriting the
241 flash contents can render your computer unbootable. On no account
242 allow random users access to this device. :-)
244 To compile this driver as a module, choose M here: the
245 module will be called nwflash.
247 If you're not sure, say N.
249 source "drivers/char/hw_random/Kconfig"
252 tristate "/dev/nvram support"
253 depends on ATARI || X86 || (ARM && RTC_DRV_CMOS) || GENERIC_NVRAM
255 If you say Y here and create a character special file /dev/nvram
256 with major number 10 and minor number 144 using mknod ("man mknod"),
257 you get read and write access to the extra bytes of non-volatile
258 memory in the real time clock (RTC), which is contained in every PC
259 and most Ataris. The actual number of bytes varies, depending on the
260 nvram in the system, but is usually 114 (128-14 for the RTC).
262 This memory is conventionally called "CMOS RAM" on PCs and "NVRAM"
263 on Ataris. /dev/nvram may be used to view settings there, or to
264 change them (with some utility). It could also be used to frequently
265 save a few bits of very important data that may not be lost over
266 power-off and for which writing to disk is too insecure. Note
267 however that most NVRAM space in a PC belongs to the BIOS and you
268 should NEVER idly tamper with it. See Ralf Brown's interrupt list
269 for a guide to the use of CMOS bytes by your BIOS.
271 On Atari machines, /dev/nvram is always configured and does not need
274 To compile this driver as a module, choose M here: the
275 module will be called nvram.
278 # These legacy RTC drivers just cause too many conflicts with the generic
279 # RTC framework ... let's not even try to coexist any more.
284 tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
285 depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
286 && !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN && !UML
288 If you say Y here and create a character special file /dev/rtc with
289 major number 10 and minor number 135 using mknod ("man mknod"), you
290 will get access to the real time clock (or hardware clock) built
293 Every PC has such a clock built in. It can be used to generate
294 signals from as low as 1Hz up to 8192Hz, and can also be used
295 as a 24 hour alarm. It reports status information via the file
296 /proc/driver/rtc and its behaviour is set by various ioctls on
299 If you run Linux on a multiprocessor machine and said Y to
300 "Symmetric Multi Processing" above, you should say Y here to read
301 and set the RTC in an SMP compatible fashion.
303 If you think you have a use for such a device (such as periodic data
304 sampling), then say Y here, and read <file:Documentation/rtc.txt>
307 To compile this driver as a module, choose M here: the
308 module will be called rtc.
311 tristate "Enhanced Real Time Clock Support"
312 depends on SPARC32 && PCI
314 If you say Y here and create a character special file /dev/rtc with
315 major number 10 and minor number 135 using mknod ("man mknod"), you
316 will get access to the real time clock (or hardware clock) built
319 Every PC has such a clock built in. It can be used to generate
320 signals from as low as 1Hz up to 8192Hz, and can also be used
321 as a 24 hour alarm. It reports status information via the file
322 /proc/driver/rtc and its behaviour is set by various ioctls on
325 If you think you have a use for such a device (such as periodic data
326 sampling), then say Y here, and read <file:Documentation/rtc.txt>
329 To compile this driver as a module, choose M here: the
330 module will be called js-rtc.
333 tristate "Generic /dev/rtc emulation"
334 depends on RTC!=y && !IA64 && !ARM && !M32R && !MIPS && !SPARC && !FRV && !S390 && !SUPERH && !AVR32 && !BLACKFIN && !UML
336 If you say Y here and create a character special file /dev/rtc with
337 major number 10 and minor number 135 using mknod ("man mknod"), you
338 will get access to the real time clock (or hardware clock) built
341 It reports status information via the file /proc/driver/rtc and its
342 behaviour is set by various ioctls on /dev/rtc. If you enable the
343 "extended RTC operation" below it will also provide an emulation
344 for RTC_UIE which is required by some programs and may improve
345 precision in some cases.
347 To compile this driver as a module, choose M here: the
348 module will be called genrtc.
351 bool "Extended RTC operation"
354 Provides an emulation for RTC_UIE which is required by some programs
355 and may improve precision of the generic RTC support in some cases.
358 bool "EFI Real Time Clock Services"
362 tristate "DS1302 RTC support"
363 depends on M32R && (PLAT_M32700UT || PLAT_OPSPUT)
365 If you say Y here and create a character special file /dev/rtc with
366 major number 121 and minor number 0 using mknod ("man mknod"), you
367 will get access to the real time clock (or hardware clock) built
373 tristate "Double Talk PC internal speech card support"
376 This driver is for the DoubleTalk PC, a speech synthesizer
377 manufactured by RC Systems (<http://www.rcsys.com/>). It is also
378 called the `internal DoubleTalk'.
380 To compile this driver as a module, choose M here: the
381 module will be called dtlk.
384 tristate "Xilinx HWICAP Support"
385 depends on XILINX_VIRTEX || MICROBLAZE
387 This option enables support for Xilinx Internal Configuration
388 Access Port (ICAP) driver. The ICAP is used on Xilinx Virtex
389 FPGA platforms to partially reconfigure the FPGA at runtime.
394 tristate "Siemens R3964 line discipline"
396 This driver allows synchronous communication with devices using the
397 Siemens R3964 packet protocol. Unless you are dealing with special
398 hardware like PLCs, you are unlikely to need this.
400 To compile this driver as a module, choose M here: the
401 module will be called n_r3964.
406 tristate "Applicom intelligent fieldbus card support"
409 This driver provides the kernel-side support for the intelligent
410 fieldbus cards made by Applicom International. More information
411 about these cards can be found on the WWW at the address
412 <http://www.applicom-int.com/>, or by email from David Woodhouse
413 <dwmw2@infradead.org>.
415 To compile this driver as a module, choose M here: the
416 module will be called applicom.
421 tristate "Sony Vaio Programmable I/O Control Device support (EXPERIMENTAL)"
422 depends on EXPERIMENTAL && X86 && PCI && INPUT && !64BIT
424 This driver enables access to the Sony Programmable I/O Control
425 Device which can be found in many (all ?) Sony Vaio laptops.
427 If you have one of those laptops, read
428 <file:Documentation/laptops/sonypi.txt>, and say Y or M here.
430 To compile this driver as a module, choose M here: the
431 module will be called sonypi.
434 tristate "TANBAC TB0219 GPIO support"
435 depends on TANBAC_TB022X
438 source "drivers/char/pcmcia/Kconfig"
441 tristate "ACP Modem (Mwave) support"
445 The ACP modem (Mwave) for Linux is a WinModem. It is composed of a
446 kernel driver and a user level application. Together these components
447 support direct attachment to public switched telephone networks (PSTNs)
448 and support selected world wide countries.
450 This version of the ACP Modem driver supports the IBM Thinkpad 600E,
451 600, and 770 that include on board ACP modem hardware.
453 The modem also supports the standard communications port interface
454 (ttySx) and is compatible with the Hayes AT Command Set.
456 The user level application needed to use this driver can be found at
457 the IBM Linux Technology Center (LTC) web site:
458 <http://www.ibm.com/linux/ltc/>.
460 If you own one of the above IBM Thinkpads which has the Mwave chipset
463 To compile this driver as a module, choose M here: the
464 module will be called mwave.
467 tristate "NatSemi SCx200 GPIO Support"
471 Give userspace access to the GPIO pins on the National
472 Semiconductor SCx200 processors.
474 If compiled as a module, it will be called scx200_gpio.
477 tristate "NatSemi PC8736x GPIO Support"
478 depends on X86_32 && !UML
479 default SCx200_GPIO # mostly N
480 select NSC_GPIO # needed for support routines
482 Give userspace access to the GPIO pins on the National
483 Semiconductor PC-8736x (x=[03456]) SuperIO chip. The chip
484 has multiple functional units, inc several managed by
485 hwmon/pc87360 driver. Tested with PC-87366
487 If compiled as a module, it will be called pc8736x_gpio.
490 tristate "NatSemi Base GPIO Support"
492 # selected by SCx200_GPIO and PC8736x_GPIO
493 # what about 2 selectors differing: m != y
495 Common support used (and needed) by scx200_gpio and
496 pc8736x_gpio drivers. If those drivers are built as
497 modules, this one will be too, named nsc_gpio
500 tristate "RAW driver (/dev/raw/rawN)"
503 The raw driver permits block devices to be bound to /dev/raw/rawN.
504 Once bound, I/O against /dev/raw/rawN uses efficient zero-copy I/O.
505 See the raw(8) manpage for more details.
507 Applications should preferably open the device (eg /dev/hda1)
508 with the O_DIRECT flag.
511 int "Maximum number of RAW devices to support (1-65536)"
512 depends on RAW_DRIVER
515 The maximum number of RAW devices that are supported.
516 Default is 256. Increase this number in case you need lots of
520 bool "HPET - High Precision Event Timer" if (X86 || IA64)
524 If you say Y here, you will have a miscdevice named "/dev/hpet/". Each
525 open selects one of the timers supported by the HPET. The timers are
526 non-periodic and/or periodic.
529 bool "Allow mmap of HPET"
533 If you say Y here, user applications will be able to mmap
536 In some hardware implementations, the page containing HPET
537 registers may also contain other things that shouldn't be
538 exposed to the user. If this applies to your hardware,
541 config HANGCHECK_TIMER
542 tristate "Hangcheck timer"
543 depends on X86 || IA64 || PPC64 || S390
545 The hangcheck-timer module detects when the system has gone
546 out to lunch past a certain margin. It can reboot the system
547 or merely print a warning.
550 tristate "MMTIMER Memory mapped RTC for SGI Altix"
551 depends on IA64_GENERIC || IA64_SGI_SN2
554 The mmtimer device allows direct userspace access to the
558 tristate "UV_MMTIMER Memory mapped RTC for SGI UV"
562 The uv_mmtimer device allows direct userspace access to the
565 source "drivers/char/tpm/Kconfig"
568 tristate "Telecom clock driver for ATCA SBC"
569 depends on EXPERIMENTAL && X86
572 The telecom clock device is specific to the MPCBL0010 and MPCBL0050
573 ATCA computers and allows direct userspace access to the
574 configuration of the telecom clock configuration settings. This
575 device is used for hardware synchronization across the ATCA backplane
576 fabric. Upon loading, the driver exports a sysfs directory,
577 /sys/devices/platform/telco_clock, with a number of files for
578 controlling the behavior of this hardware.
583 depends on ISA || PCI
586 source "drivers/s390/char/Kconfig"
589 tristate "Log panic/oops to a RAM buffer"
593 This enables panic and oops messages to be logged to a circular
594 buffer in RAM where it can be read back at some later point.
597 bool "Enable device interface for some SMD packet ports"
601 Enables userspace clients to read and write to some packet SMD
602 ports via device interface for MSM chipset.
605 bool "Character-device access via hypervisor to the Tilera SPI ROM"
609 This device provides character-level read-write access
610 to the SROM, typically via the "0", "1", and "2" devices
611 in /dev/srom/. The Tilera hypervisor makes the flash
612 device appear much like a simple EEPROM, and knows
613 how to partition a single ROM for multiple purposes.