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"
21 Say Y here if you want to support the /dev/kmem device. The
22 /dev/kmem device is rarely used, but can be used for certain
23 kind of kernel debugging operations.
24 When in doubt, say "N".
27 bool "SGI Altix system controller communication support"
28 depends on (IA64_SGI_SN2 || IA64_GENERIC)
30 If you have an SGI Altix and you want to enable system
31 controller communication from user space (you want this!),
32 say Y. Otherwise, say N.
35 bool "SGI TIO CX driver support"
36 depends on (IA64_SGI_SN2 || IA64_GENERIC)
38 If you have an SGI Altix and you have fpga devices attached
39 to your TIO, say Y here, otherwise say N.
42 tristate "SGI FPGA Core Services driver support"
45 If you have an SGI Altix with an attached SABrick
46 say Y or M here, otherwise say N.
48 source "drivers/tty/serial/Kconfig"
51 tristate "TTY driver to output user messages via printk"
52 depends on EXPERT && TTY
55 If you say Y here, the support for writing user messages (i.e.
56 console messages) via printk is available.
58 The feature is useful to inline user messages with kernel
60 In order to use this feature, you should output user messages
61 to /dev/ttyprintk or redirect console to this TTY.
66 tristate "Blackfin On-Chip OTP Memory Support"
67 depends on BLACKFIN && (BF51x || BF52x || BF54x)
70 If you say Y here, you will get support for a character device
71 interface into the One Time Programmable memory pages that are
72 stored on the Blackfin processor. This will not get you access
73 to the secure memory pages however. You will need to write your
74 own secure code and reader for that.
76 To compile this driver as a module, choose M here: the module
77 will be called bfin-otp.
79 If unsure, it is safe to say Y.
81 config BFIN_OTP_WRITE_ENABLE
82 bool "Enable writing support of OTP pages"
86 If you say Y here, you will enable support for writing of the
87 OTP pages. This is dangerous by nature as you can only program
88 the pages once, so only enable this option when you actually
89 need it so as to not inadvertently clobber data.
94 tristate "Parallel printer support"
97 If you intend to attach a printer to the parallel port of your Linux
98 box (as opposed to using a serial printer; if the connector at the
99 printer has 9 or 25 holes ["female"], then it's serial), say Y.
100 Also read the Printing-HOWTO, available from
101 <http://www.tldp.org/docs.html#howto>.
103 It is possible to share one parallel port among several devices
104 (e.g. printer and ZIP drive) and it is safe to compile the
105 corresponding drivers into the kernel.
107 To compile this driver as a module, choose M here and read
108 <file:Documentation/parport.txt>. The module will be called lp.
110 If you have several parallel ports, you can specify which ports to
111 use with the "lp" kernel command line option. (Try "man bootparam"
112 or see the documentation of your boot loader (lilo or loadlin) about
113 how to pass options to the kernel at boot time.) The syntax of the
114 "lp" command line option can be found in <file:drivers/char/lp.c>.
116 If you have more than 8 printers, you need to increase the LP_NO
117 macro in lp.c and the PARPORT_MAX macro in parport.h.
120 bool "Support for console on line printer"
123 If you want kernel messages to be printed out as they occur, you
124 can have a console on the printer. This option adds support for
125 doing that; to actually get it to happen you need to pass the
126 option "console=lp0" to the kernel at boot time.
128 If the printer is out of paper (or off, or unplugged, or too
129 busy..) the kernel will stall until the printer is ready again.
130 By defining CONSOLE_LP_STRICT to 0 (at your own risk) you
131 can make the kernel continue when this happens,
132 but it'll lose the kernel messages.
137 tristate "Support for user-space parallel port device drivers"
140 Saying Y to this adds support for /dev/parport device nodes. This
141 is needed for programs that want portable access to the parallel
142 port, for instance deviceid (which displays Plug-and-Play device
145 This is the parallel port equivalent of SCSI generic support (sg).
146 It is safe to say N to this -- it is not needed for normal printing
147 or parallel port CD-ROM/disk support.
149 To compile this driver as a module, choose M here: the
150 module will be called ppdev.
154 source "drivers/tty/hvc/Kconfig"
156 config VIRTIO_CONSOLE
157 tristate "Virtio console"
158 depends on VIRTIO && TTY
161 Virtio console for use with lguest and other hypervisors.
163 Also serves as a general-purpose serial device for data
164 transfer between the guest and host. Character devices at
165 /dev/vportNpn will be created when corresponding ports are
166 found, where N is the device number and n is the port number
167 within that device. If specified by the host, a sysfs
168 attribute called 'name' will be populated with a name for
169 the port which can be used by udev scripts to create a
170 symlink to the device.
173 tristate "IBM POWER Barrier Synchronization Register support"
174 depends on PPC_PSERIES
176 This devices exposes a hardware mechanism for fast synchronization
177 of threads across a large system which avoids bouncing a cacheline
178 between several cores on a system
180 config POWERNV_OP_PANEL
181 tristate "IBM POWERNV Operator Panel Display support"
182 depends on PPC_POWERNV
185 If you say Y here, a special character device node, /dev/op_panel,
186 will be created which exposes the operator panel display on IBM
187 Power Systems machines with FSPs.
189 If you don't require access to the operator panel display from user
192 If unsure, say M here to build it as a module called powernv-op-panel.
194 source "drivers/char/ipmi/Kconfig"
197 tristate "NetWinder thermometer support"
198 depends on ARCH_NETWINDER
200 Say Y here to include support for the thermal management hardware
201 found in the NetWinder. This driver allows the user to control the
202 temperature set points and to read the current temperature.
204 It is also possible to say M here to build it as a module (ds1620)
205 It is recommended to be used on a NetWinder, but it is not a
209 tristate "NetWinder Button"
210 depends on ARCH_NETWINDER
212 If you say Y here and create a character device node /dev/nwbutton
213 with major and minor numbers 10 and 158 ("man mknod"), then every
214 time the orange button is pressed a number of times, the number of
215 times the button was pressed will be written to that device.
217 This is most useful for applications, as yet unwritten, which
218 perform actions based on how many times the button is pressed in a
221 Do not hold the button down for too long, as the driver does not
222 alter the behaviour of the hardware reset circuitry attached to the
223 button; it will still execute a hard reset if the button is held
224 down for longer than approximately five seconds.
226 To compile this driver as a module, choose M here: the
227 module will be called nwbutton.
229 Most people will answer Y to this question and "Reboot Using Button"
230 below to be able to initiate a system shutdown from the button.
232 config NWBUTTON_REBOOT
233 bool "Reboot Using Button"
236 If you say Y here, then you will be able to initiate a system
237 shutdown and reboot by pressing the orange button a number of times.
238 The number of presses to initiate the shutdown is two by default,
239 but this can be altered by modifying the value of NUM_PRESSES_REBOOT
240 in nwbutton.h and recompiling the driver or, if you compile the
241 driver as a module, you can specify the number of presses at load
242 time with "insmod button reboot_count=<something>".
245 tristate "NetWinder flash support"
246 depends on ARCH_NETWINDER
248 If you say Y here and create a character device /dev/flash with
249 major 10 and minor 160 you can manipulate the flash ROM containing
250 the NetWinder firmware. Be careful as accidentally overwriting the
251 flash contents can render your computer unbootable. On no account
252 allow random users access to this device. :-)
254 To compile this driver as a module, choose M here: the
255 module will be called nwflash.
257 If you're not sure, say N.
259 source "drivers/char/hw_random/Kconfig"
262 tristate "/dev/nvram support"
263 depends on ATARI || X86 || (ARM && RTC_DRV_CMOS) || GENERIC_NVRAM
265 If you say Y here and create a character special file /dev/nvram
266 with major number 10 and minor number 144 using mknod ("man mknod"),
267 you get read and write access to the extra bytes of non-volatile
268 memory in the real time clock (RTC), which is contained in every PC
269 and most Ataris. The actual number of bytes varies, depending on the
270 nvram in the system, but is usually 114 (128-14 for the RTC).
272 This memory is conventionally called "CMOS RAM" on PCs and "NVRAM"
273 on Ataris. /dev/nvram may be used to view settings there, or to
274 change them (with some utility). It could also be used to frequently
275 save a few bits of very important data that may not be lost over
276 power-off and for which writing to disk is too insecure. Note
277 however that most NVRAM space in a PC belongs to the BIOS and you
278 should NEVER idly tamper with it. See Ralf Brown's interrupt list
279 for a guide to the use of CMOS bytes by your BIOS.
281 On Atari machines, /dev/nvram is always configured and does not need
284 To compile this driver as a module, choose M here: the
285 module will be called nvram.
288 # These legacy RTC drivers just cause too many conflicts with the generic
289 # RTC framework ... let's not even try to coexist any more.
294 tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
295 depends on ALPHA || (MIPS && MACH_LOONGSON64)
297 If you say Y here and create a character special file /dev/rtc with
298 major number 10 and minor number 135 using mknod ("man mknod"), you
299 will get access to the real time clock (or hardware clock) built
302 Every PC has such a clock built in. It can be used to generate
303 signals from as low as 1Hz up to 8192Hz, and can also be used
304 as a 24 hour alarm. It reports status information via the file
305 /proc/driver/rtc and its behaviour is set by various ioctls on
308 If you run Linux on a multiprocessor machine and said Y to
309 "Symmetric Multi Processing" above, you should say Y here to read
310 and set the RTC in an SMP compatible fashion.
312 If you think you have a use for such a device (such as periodic data
313 sampling), then say Y here, and read <file:Documentation/rtc.txt>
316 To compile this driver as a module, choose M here: the
317 module will be called rtc.
320 tristate "Enhanced Real Time Clock Support"
321 depends on SPARC32 && PCI
323 If you say Y here and create a character special file /dev/rtc with
324 major number 10 and minor number 135 using mknod ("man mknod"), you
325 will get access to the real time clock (or hardware clock) built
328 Every PC has such a clock built in. It can be used to generate
329 signals from as low as 1Hz up to 8192Hz, and can also be used
330 as a 24 hour alarm. It reports status information via the file
331 /proc/driver/rtc and its behaviour is set by various ioctls on
334 If you think you have a use for such a device (such as periodic data
335 sampling), then say Y here, and read <file:Documentation/rtc.txt>
338 To compile this driver as a module, choose M here: the
339 module will be called js-rtc.
342 bool "EFI Real Time Clock Services"
346 tristate "DS1302 RTC support"
347 depends on M32R && (PLAT_M32700UT || PLAT_OPSPUT)
349 If you say Y here and create a character special file /dev/rtc with
350 major number 121 and minor number 0 using mknod ("man mknod"), you
351 will get access to the real time clock (or hardware clock) built
357 tristate "Double Talk PC internal speech card support"
360 This driver is for the DoubleTalk PC, a speech synthesizer
361 manufactured by RC Systems (<http://www.rcsys.com/>). It is also
362 called the `internal DoubleTalk'.
364 To compile this driver as a module, choose M here: the
365 module will be called dtlk.
368 tristate "Xilinx HWICAP Support"
369 depends on XILINX_VIRTEX || MICROBLAZE
371 This option enables support for Xilinx Internal Configuration
372 Access Port (ICAP) driver. The ICAP is used on Xilinx Virtex
373 FPGA platforms to partially reconfigure the FPGA at runtime.
378 tristate "Siemens R3964 line discipline"
381 This driver allows synchronous communication with devices using the
382 Siemens R3964 packet protocol. Unless you are dealing with special
383 hardware like PLCs, you are unlikely to need this.
385 To compile this driver as a module, choose M here: the
386 module will be called n_r3964.
391 tristate "Applicom intelligent fieldbus card support"
394 This driver provides the kernel-side support for the intelligent
395 fieldbus cards made by Applicom International. More information
396 about these cards can be found on the WWW at the address
397 <http://www.applicom-int.com/>, or by email from David Woodhouse
398 <dwmw2@infradead.org>.
400 To compile this driver as a module, choose M here: the
401 module will be called applicom.
406 tristate "Sony Vaio Programmable I/O Control Device support"
407 depends on X86_32 && PCI && INPUT
409 This driver enables access to the Sony Programmable I/O Control
410 Device which can be found in many (all ?) Sony Vaio laptops.
412 If you have one of those laptops, read
413 <file:Documentation/laptops/sonypi.txt>, and say Y or M here.
415 To compile this driver as a module, choose M here: the
416 module will be called sonypi.
419 tristate "TANBAC TB0219 GPIO support"
420 depends on TANBAC_TB022X
423 source "drivers/char/pcmcia/Kconfig"
426 tristate "ACP Modem (Mwave) support"
427 depends on X86 && TTY
430 The ACP modem (Mwave) for Linux is a WinModem. It is composed of a
431 kernel driver and a user level application. Together these components
432 support direct attachment to public switched telephone networks (PSTNs)
433 and support selected world wide countries.
435 This version of the ACP Modem driver supports the IBM Thinkpad 600E,
436 600, and 770 that include on board ACP modem hardware.
438 The modem also supports the standard communications port interface
439 (ttySx) and is compatible with the Hayes AT Command Set.
441 The user level application needed to use this driver can be found at
442 the IBM Linux Technology Center (LTC) web site:
443 <http://www.ibm.com/linux/ltc/>.
445 If you own one of the above IBM Thinkpads which has the Mwave chipset
448 To compile this driver as a module, choose M here: the
449 module will be called mwave.
452 tristate "NatSemi SCx200 GPIO Support"
456 Give userspace access to the GPIO pins on the National
457 Semiconductor SCx200 processors.
459 If compiled as a module, it will be called scx200_gpio.
462 tristate "NatSemi PC8736x GPIO Support"
463 depends on X86_32 && !UML
464 default SCx200_GPIO # mostly N
465 select NSC_GPIO # needed for support routines
467 Give userspace access to the GPIO pins on the National
468 Semiconductor PC-8736x (x=[03456]) SuperIO chip. The chip
469 has multiple functional units, inc several managed by
470 hwmon/pc87360 driver. Tested with PC-87366
472 If compiled as a module, it will be called pc8736x_gpio.
475 tristate "NatSemi Base GPIO Support"
477 # selected by SCx200_GPIO and PC8736x_GPIO
478 # what about 2 selectors differing: m != y
480 Common support used (and needed) by scx200_gpio and
481 pc8736x_gpio drivers. If those drivers are built as
482 modules, this one will be too, named nsc_gpio
485 tristate "RAW driver (/dev/raw/rawN)"
488 The raw driver permits block devices to be bound to /dev/raw/rawN.
489 Once bound, I/O against /dev/raw/rawN uses efficient zero-copy I/O.
490 See the raw(8) manpage for more details.
492 Applications should preferably open the device (eg /dev/hda1)
493 with the O_DIRECT flag.
496 int "Maximum number of RAW devices to support (1-65536)"
497 depends on RAW_DRIVER
501 The maximum number of RAW devices that are supported.
502 Default is 256. Increase this number in case you need lots of
506 bool "HPET - High Precision Event Timer" if (X86 || IA64)
510 If you say Y here, you will have a miscdevice named "/dev/hpet/". Each
511 open selects one of the timers supported by the HPET. The timers are
512 non-periodic and/or periodic.
515 bool "Allow mmap of HPET"
519 If you say Y here, user applications will be able to mmap
522 config HPET_MMAP_DEFAULT
523 bool "Enable HPET MMAP access by default"
527 In some hardware implementations, the page containing HPET
528 registers may also contain other things that shouldn't be
529 exposed to the user. This option selects the default (if
530 kernel parameter hpet_mmap is not set) user access to the
531 registers for applications that require it.
533 config HANGCHECK_TIMER
534 tristate "Hangcheck timer"
535 depends on X86 || IA64 || PPC64 || S390
537 The hangcheck-timer module detects when the system has gone
538 out to lunch past a certain margin. It can reboot the system
539 or merely print a warning.
542 tristate "MMTIMER Memory mapped RTC for SGI Altix"
543 depends on IA64_GENERIC || IA64_SGI_SN2
544 depends on POSIX_TIMERS
547 The mmtimer device allows direct userspace access to the
551 tristate "UV_MMTIMER Memory mapped RTC for SGI UV"
555 The uv_mmtimer device allows direct userspace access to the
558 source "drivers/char/tpm/Kconfig"
561 tristate "Telecom clock driver for ATCA SBC"
565 The telecom clock device is specific to the MPCBL0010 and MPCBL0050
566 ATCA computers and allows direct userspace access to the
567 configuration of the telecom clock configuration settings. This
568 device is used for hardware synchronization across the ATCA backplane
569 fabric. Upon loading, the driver exports a sysfs directory,
570 /sys/devices/platform/telco_clock, with a number of files for
571 controlling the behavior of this hardware.
575 depends on ISA || PCI
578 source "drivers/s390/char/Kconfig"
581 tristate "Character-device access via hypervisor to the Tilera SPI ROM"
585 This device provides character-level read-write access
586 to the SROM, typically via the "0", "1", and "2" devices
587 in /dev/srom/. The Tilera hypervisor makes the flash
588 device appear much like a simple EEPROM, and knows
589 how to partition a single ROM for multiple purposes.
591 source "drivers/char/xillybus/Kconfig"