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 'Total Impact briQ front panel driver'
73 The briQ is a small footprint CHRP computer with a frontpanel VFD, a
74 tristate led and two switches. It is the size of a CDROM drive.
76 If you have such one and want anything showing on the VFD then you
79 To compile this driver as a module, choose M here: the
80 module will be called briq_panel.
82 It's safe to say N here.
85 tristate "Blackfin On-Chip OTP Memory Support"
86 depends on BLACKFIN && (BF51x || BF52x || BF54x)
89 If you say Y here, you will get support for a character device
90 interface into the One Time Programmable memory pages that are
91 stored on the Blackfin processor. This will not get you access
92 to the secure memory pages however. You will need to write your
93 own secure code and reader for that.
95 To compile this driver as a module, choose M here: the module
96 will be called bfin-otp.
98 If unsure, it is safe to say Y.
100 config BFIN_OTP_WRITE_ENABLE
101 bool "Enable writing support of OTP pages"
105 If you say Y here, you will enable support for writing of the
106 OTP pages. This is dangerous by nature as you can only program
107 the pages once, so only enable this option when you actually
108 need it so as to not inadvertently clobber data.
113 tristate "Parallel printer support"
116 If you intend to attach a printer to the parallel port of your Linux
117 box (as opposed to using a serial printer; if the connector at the
118 printer has 9 or 25 holes ["female"], then it's serial), say Y.
119 Also read the Printing-HOWTO, available from
120 <http://www.tldp.org/docs.html#howto>.
122 It is possible to share one parallel port among several devices
123 (e.g. printer and ZIP drive) and it is safe to compile the
124 corresponding drivers into the kernel.
126 To compile this driver as a module, choose M here and read
127 <file:Documentation/parport.txt>. The module will be called lp.
129 If you have several parallel ports, you can specify which ports to
130 use with the "lp" kernel command line option. (Try "man bootparam"
131 or see the documentation of your boot loader (lilo or loadlin) about
132 how to pass options to the kernel at boot time.) The syntax of the
133 "lp" command line option can be found in <file:drivers/char/lp.c>.
135 If you have more than 8 printers, you need to increase the LP_NO
136 macro in lp.c and the PARPORT_MAX macro in parport.h.
139 bool "Support for console on line printer"
142 If you want kernel messages to be printed out as they occur, you
143 can have a console on the printer. This option adds support for
144 doing that; to actually get it to happen you need to pass the
145 option "console=lp0" to the kernel at boot time.
147 If the printer is out of paper (or off, or unplugged, or too
148 busy..) the kernel will stall until the printer is ready again.
149 By defining CONSOLE_LP_STRICT to 0 (at your own risk) you
150 can make the kernel continue when this happens,
151 but it'll lose the kernel messages.
156 tristate "Support for user-space parallel port device drivers"
159 Saying Y to this adds support for /dev/parport device nodes. This
160 is needed for programs that want portable access to the parallel
161 port, for instance deviceid (which displays Plug-and-Play device
164 This is the parallel port equivalent of SCSI generic support (sg).
165 It is safe to say N to this -- it is not needed for normal printing
166 or parallel port CD-ROM/disk support.
168 To compile this driver as a module, choose M here: the
169 module will be called ppdev.
173 source "drivers/tty/hvc/Kconfig"
175 config VIRTIO_CONSOLE
176 tristate "Virtio console"
180 Virtio console for use with lguest and other hypervisors.
182 Also serves as a general-purpose serial device for data
183 transfer between the guest and host. Character devices at
184 /dev/vportNpn will be created when corresponding ports are
185 found, where N is the device number and n is the port number
186 within that device. If specified by the host, a sysfs
187 attribute called 'name' will be populated with a name for
188 the port which can be used by udev scripts to create a
189 symlink to the device.
192 tristate "IBM POWER Barrier Synchronization Register support"
193 depends on PPC_PSERIES
195 This devices exposes a hardware mechanism for fast synchronization
196 of threads across a large system which avoids bouncing a cacheline
197 between several cores on a system
199 source "drivers/char/ipmi/Kconfig"
202 tristate "NetWinder thermometer support"
203 depends on ARCH_NETWINDER
205 Say Y here to include support for the thermal management hardware
206 found in the NetWinder. This driver allows the user to control the
207 temperature set points and to read the current temperature.
209 It is also possible to say M here to build it as a module (ds1620)
210 It is recommended to be used on a NetWinder, but it is not a
214 tristate "NetWinder Button"
215 depends on ARCH_NETWINDER
217 If you say Y here and create a character device node /dev/nwbutton
218 with major and minor numbers 10 and 158 ("man mknod"), then every
219 time the orange button is pressed a number of times, the number of
220 times the button was pressed will be written to that device.
222 This is most useful for applications, as yet unwritten, which
223 perform actions based on how many times the button is pressed in a
226 Do not hold the button down for too long, as the driver does not
227 alter the behaviour of the hardware reset circuitry attached to the
228 button; it will still execute a hard reset if the button is held
229 down for longer than approximately five seconds.
231 To compile this driver as a module, choose M here: the
232 module will be called nwbutton.
234 Most people will answer Y to this question and "Reboot Using Button"
235 below to be able to initiate a system shutdown from the button.
237 config NWBUTTON_REBOOT
238 bool "Reboot Using Button"
241 If you say Y here, then you will be able to initiate a system
242 shutdown and reboot by pressing the orange button a number of times.
243 The number of presses to initiate the shutdown is two by default,
244 but this can be altered by modifying the value of NUM_PRESSES_REBOOT
245 in nwbutton.h and recompiling the driver or, if you compile the
246 driver as a module, you can specify the number of presses at load
247 time with "insmod button reboot_count=<something>".
250 tristate "NetWinder flash support"
251 depends on ARCH_NETWINDER
253 If you say Y here and create a character device /dev/flash with
254 major 10 and minor 160 you can manipulate the flash ROM containing
255 the NetWinder firmware. Be careful as accidentally overwriting the
256 flash contents can render your computer unbootable. On no account
257 allow random users access to this device. :-)
259 To compile this driver as a module, choose M here: the
260 module will be called nwflash.
262 If you're not sure, say N.
264 source "drivers/char/hw_random/Kconfig"
267 tristate "/dev/nvram support"
268 depends on ATARI || X86 || (ARM && RTC_DRV_CMOS) || GENERIC_NVRAM
270 If you say Y here and create a character special file /dev/nvram
271 with major number 10 and minor number 144 using mknod ("man mknod"),
272 you get read and write access to the extra bytes of non-volatile
273 memory in the real time clock (RTC), which is contained in every PC
274 and most Ataris. The actual number of bytes varies, depending on the
275 nvram in the system, but is usually 114 (128-14 for the RTC).
277 This memory is conventionally called "CMOS RAM" on PCs and "NVRAM"
278 on Ataris. /dev/nvram may be used to view settings there, or to
279 change them (with some utility). It could also be used to frequently
280 save a few bits of very important data that may not be lost over
281 power-off and for which writing to disk is too insecure. Note
282 however that most NVRAM space in a PC belongs to the BIOS and you
283 should NEVER idly tamper with it. See Ralf Brown's interrupt list
284 for a guide to the use of CMOS bytes by your BIOS.
286 On Atari machines, /dev/nvram is always configured and does not need
289 To compile this driver as a module, choose M here: the
290 module will be called nvram.
293 # These legacy RTC drivers just cause too many conflicts with the generic
294 # RTC framework ... let's not even try to coexist any more.
299 tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
300 depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
301 && !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN
303 If you say Y here and create a character special file /dev/rtc with
304 major number 10 and minor number 135 using mknod ("man mknod"), you
305 will get access to the real time clock (or hardware clock) built
308 Every PC has such a clock built in. It can be used to generate
309 signals from as low as 1Hz up to 8192Hz, and can also be used
310 as a 24 hour alarm. It reports status information via the file
311 /proc/driver/rtc and its behaviour is set by various ioctls on
314 If you run Linux on a multiprocessor machine and said Y to
315 "Symmetric Multi Processing" above, you should say Y here to read
316 and set the RTC in an SMP compatible fashion.
318 If you think you have a use for such a device (such as periodic data
319 sampling), then say Y here, and read <file:Documentation/rtc.txt>
322 To compile this driver as a module, choose M here: the
323 module will be called rtc.
326 tristate "Enhanced Real Time Clock Support"
327 depends on SPARC32 && PCI
329 If you say Y here and create a character special file /dev/rtc with
330 major number 10 and minor number 135 using mknod ("man mknod"), you
331 will get access to the real time clock (or hardware clock) built
334 Every PC has such a clock built in. It can be used to generate
335 signals from as low as 1Hz up to 8192Hz, and can also be used
336 as a 24 hour alarm. It reports status information via the file
337 /proc/driver/rtc and its behaviour is set by various ioctls on
340 If you think you have a use for such a device (such as periodic data
341 sampling), then say Y here, and read <file:Documentation/rtc.txt>
344 To compile this driver as a module, choose M here: the
345 module will be called js-rtc.
348 tristate "Generic /dev/rtc emulation"
349 depends on RTC!=y && !IA64 && !ARM && !M32R && !MIPS && !SPARC && !FRV && !S390 && !SUPERH && !AVR32 && !BLACKFIN
351 If you say Y here and create a character special file /dev/rtc with
352 major number 10 and minor number 135 using mknod ("man mknod"), you
353 will get access to the real time clock (or hardware clock) built
356 It reports status information via the file /proc/driver/rtc and its
357 behaviour is set by various ioctls on /dev/rtc. If you enable the
358 "extended RTC operation" below it will also provide an emulation
359 for RTC_UIE which is required by some programs and may improve
360 precision in some cases.
362 To compile this driver as a module, choose M here: the
363 module will be called genrtc.
366 bool "Extended RTC operation"
369 Provides an emulation for RTC_UIE which is required by some programs
370 and may improve precision of the generic RTC support in some cases.
373 bool "EFI Real Time Clock Services"
377 tristate "DS1302 RTC support"
378 depends on M32R && (PLAT_M32700UT || PLAT_OPSPUT)
380 If you say Y here and create a character special file /dev/rtc with
381 major number 121 and minor number 0 using mknod ("man mknod"), you
382 will get access to the real time clock (or hardware clock) built
388 tristate "Double Talk PC internal speech card support"
391 This driver is for the DoubleTalk PC, a speech synthesizer
392 manufactured by RC Systems (<http://www.rcsys.com/>). It is also
393 called the `internal DoubleTalk'.
395 To compile this driver as a module, choose M here: the
396 module will be called dtlk.
399 tristate "Xilinx HWICAP Support"
400 depends on XILINX_VIRTEX || MICROBLAZE
402 This option enables support for Xilinx Internal Configuration
403 Access Port (ICAP) driver. The ICAP is used on Xilinx Virtex
404 FPGA platforms to partially reconfigure the FPGA at runtime.
409 tristate "Siemens R3964 line discipline"
411 This driver allows synchronous communication with devices using the
412 Siemens R3964 packet protocol. Unless you are dealing with special
413 hardware like PLCs, you are unlikely to need this.
415 To compile this driver as a module, choose M here: the
416 module will be called n_r3964.
421 tristate "Applicom intelligent fieldbus card support"
424 This driver provides the kernel-side support for the intelligent
425 fieldbus cards made by Applicom International. More information
426 about these cards can be found on the WWW at the address
427 <http://www.applicom-int.com/>, or by email from David Woodhouse
428 <dwmw2@infradead.org>.
430 To compile this driver as a module, choose M here: the
431 module will be called applicom.
436 tristate "Sony Vaio Programmable I/O Control Device support (EXPERIMENTAL)"
437 depends on EXPERIMENTAL && X86 && PCI && INPUT && !64BIT
439 This driver enables access to the Sony Programmable I/O Control
440 Device which can be found in many (all ?) Sony Vaio laptops.
442 If you have one of those laptops, read
443 <file:Documentation/laptops/sonypi.txt>, and say Y or M here.
445 To compile this driver as a module, choose M here: the
446 module will be called sonypi.
449 tristate "TANBAC TB0219 GPIO support"
450 depends on TANBAC_TB022X
453 source "drivers/char/pcmcia/Kconfig"
456 tristate "ACP Modem (Mwave) support"
460 The ACP modem (Mwave) for Linux is a WinModem. It is composed of a
461 kernel driver and a user level application. Together these components
462 support direct attachment to public switched telephone networks (PSTNs)
463 and support selected world wide countries.
465 This version of the ACP Modem driver supports the IBM Thinkpad 600E,
466 600, and 770 that include on board ACP modem hardware.
468 The modem also supports the standard communications port interface
469 (ttySx) and is compatible with the Hayes AT Command Set.
471 The user level application needed to use this driver can be found at
472 the IBM Linux Technology Center (LTC) web site:
473 <http://www.ibm.com/linux/ltc/>.
475 If you own one of the above IBM Thinkpads which has the Mwave chipset
478 To compile this driver as a module, choose M here: the
479 module will be called mwave.
482 tristate "NatSemi SCx200 GPIO Support"
486 Give userspace access to the GPIO pins on the National
487 Semiconductor SCx200 processors.
489 If compiled as a module, it will be called scx200_gpio.
492 tristate "NatSemi PC8736x GPIO Support"
494 default SCx200_GPIO # mostly N
495 select NSC_GPIO # needed for support routines
497 Give userspace access to the GPIO pins on the National
498 Semiconductor PC-8736x (x=[03456]) SuperIO chip. The chip
499 has multiple functional units, inc several managed by
500 hwmon/pc87360 driver. Tested with PC-87366
502 If compiled as a module, it will be called pc8736x_gpio.
505 tristate "NatSemi Base GPIO Support"
507 # selected by SCx200_GPIO and PC8736x_GPIO
508 # what about 2 selectors differing: m != y
510 Common support used (and needed) by scx200_gpio and
511 pc8736x_gpio drivers. If those drivers are built as
512 modules, this one will be too, named nsc_gpio
515 tristate "RAW driver (/dev/raw/rawN)"
518 The raw driver permits block devices to be bound to /dev/raw/rawN.
519 Once bound, I/O against /dev/raw/rawN uses efficient zero-copy I/O.
520 See the raw(8) manpage for more details.
522 Applications should preferably open the device (eg /dev/hda1)
523 with the O_DIRECT flag.
526 int "Maximum number of RAW devices to support (1-65536)"
527 depends on RAW_DRIVER
530 The maximum number of RAW devices that are supported.
531 Default is 256. Increase this number in case you need lots of
535 bool "HPET - High Precision Event Timer" if (X86 || IA64)
539 If you say Y here, you will have a miscdevice named "/dev/hpet/". Each
540 open selects one of the timers supported by the HPET. The timers are
541 non-periodic and/or periodic.
544 bool "Allow mmap of HPET"
548 If you say Y here, user applications will be able to mmap
551 In some hardware implementations, the page containing HPET
552 registers may also contain other things that shouldn't be
553 exposed to the user. If this applies to your hardware,
556 config HANGCHECK_TIMER
557 tristate "Hangcheck timer"
558 depends on X86 || IA64 || PPC64 || S390
560 The hangcheck-timer module detects when the system has gone
561 out to lunch past a certain margin. It can reboot the system
562 or merely print a warning.
565 tristate "MMTIMER Memory mapped RTC for SGI Altix"
566 depends on IA64_GENERIC || IA64_SGI_SN2
569 The mmtimer device allows direct userspace access to the
573 tristate "UV_MMTIMER Memory mapped RTC for SGI UV"
577 The uv_mmtimer device allows direct userspace access to the
580 source "drivers/char/tpm/Kconfig"
583 tristate "Telecom clock driver for ATCA SBC"
584 depends on EXPERIMENTAL && X86
587 The telecom clock device is specific to the MPCBL0010 and MPCBL0050
588 ATCA computers and allows direct userspace access to the
589 configuration of the telecom clock configuration settings. This
590 device is used for hardware synchronization across the ATCA backplane
591 fabric. Upon loading, the driver exports a sysfs directory,
592 /sys/devices/platform/telco_clock, with a number of files for
593 controlling the behavior of this hardware.
598 depends on ISA || PCI
601 source "drivers/s390/char/Kconfig"
604 tristate "Log panic/oops to a RAM buffer"
608 This enables panic and oops messages to be logged to a circular
609 buffer in RAM where it can be read back at some later point.
612 bool "Enable device interface for some SMD packet ports"
616 Enables userspace clients to read and write to some packet SMD
617 ports via device interface for MSM chipset.
620 bool "Character-device access via hypervisor to the Tilera SPI ROM"
624 This device provides character-level read-write access
625 to the SROM, typically via the "0", "1", and "2" devices
626 in /dev/srom/. The Tilera hypervisor makes the flash
627 device appear much like a simple EEPROM, and knows
628 how to partition a single ROM for multiple purposes.