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 "SGI Altix system controller communication support"
20 depends on (IA64_SGI_SN2 || IA64_GENERIC)
22 If you have an SGI Altix and you want to enable system
23 controller communication from user space (you want this!),
24 say Y. Otherwise, say N.
27 bool "SGI TIO CX driver support"
28 depends on (IA64_SGI_SN2 || IA64_GENERIC)
30 If you have an SGI Altix and you have fpga devices attached
31 to your TIO, say Y here, otherwise say N.
34 tristate "SGI FPGA Core Services driver support"
37 If you have an SGI Altix with an attached SABrick
38 say Y or M here, otherwise say N.
40 source "drivers/tty/serial/Kconfig"
43 bool "TTY driver to output user messages via printk"
44 depends on EXPERT && TTY
47 If you say Y here, the support for writing user messages (i.e.
48 console messages) via printk is available.
50 The feature is useful to inline user messages with kernel
52 In order to use this feature, you should output user messages
53 to /dev/ttyprintk or redirect console to this TTY.
58 tristate "Blackfin On-Chip OTP Memory Support"
59 depends on BLACKFIN && (BF51x || BF52x || BF54x)
62 If you say Y here, you will get support for a character device
63 interface into the One Time Programmable memory pages that are
64 stored on the Blackfin processor. This will not get you access
65 to the secure memory pages however. You will need to write your
66 own secure code and reader for that.
68 To compile this driver as a module, choose M here: the module
69 will be called bfin-otp.
71 If unsure, it is safe to say Y.
73 config BFIN_OTP_WRITE_ENABLE
74 bool "Enable writing support of OTP pages"
78 If you say Y here, you will enable support for writing of the
79 OTP pages. This is dangerous by nature as you can only program
80 the pages once, so only enable this option when you actually
81 need it so as to not inadvertently clobber data.
86 tristate "Parallel printer support"
89 If you intend to attach a printer to the parallel port of your Linux
90 box (as opposed to using a serial printer; if the connector at the
91 printer has 9 or 25 holes ["female"], then it's serial), say Y.
92 Also read the Printing-HOWTO, available from
93 <http://www.tldp.org/docs.html#howto>.
95 It is possible to share one parallel port among several devices
96 (e.g. printer and ZIP drive) and it is safe to compile the
97 corresponding drivers into the kernel.
99 To compile this driver as a module, choose M here and read
100 <file:Documentation/parport.txt>. The module will be called lp.
102 If you have several parallel ports, you can specify which ports to
103 use with the "lp" kernel command line option. (Try "man bootparam"
104 or see the documentation of your boot loader (lilo or loadlin) about
105 how to pass options to the kernel at boot time.) The syntax of the
106 "lp" command line option can be found in <file:drivers/char/lp.c>.
108 If you have more than 8 printers, you need to increase the LP_NO
109 macro in lp.c and the PARPORT_MAX macro in parport.h.
112 bool "Support for console on line printer"
115 If you want kernel messages to be printed out as they occur, you
116 can have a console on the printer. This option adds support for
117 doing that; to actually get it to happen you need to pass the
118 option "console=lp0" to the kernel at boot time.
120 If the printer is out of paper (or off, or unplugged, or too
121 busy..) the kernel will stall until the printer is ready again.
122 By defining CONSOLE_LP_STRICT to 0 (at your own risk) you
123 can make the kernel continue when this happens,
124 but it'll lose the kernel messages.
129 tristate "Support for user-space parallel port device drivers"
132 Saying Y to this adds support for /dev/parport device nodes. This
133 is needed for programs that want portable access to the parallel
134 port, for instance deviceid (which displays Plug-and-Play device
137 This is the parallel port equivalent of SCSI generic support (sg).
138 It is safe to say N to this -- it is not needed for normal printing
139 or parallel port CD-ROM/disk support.
141 To compile this driver as a module, choose M here: the
142 module will be called ppdev.
146 source "drivers/tty/hvc/Kconfig"
148 config VIRTIO_CONSOLE
149 tristate "Virtio console"
150 depends on VIRTIO && TTY
153 Virtio console for use with lguest and other hypervisors.
155 Also serves as a general-purpose serial device for data
156 transfer between the guest and host. Character devices at
157 /dev/vportNpn will be created when corresponding ports are
158 found, where N is the device number and n is the port number
159 within that device. If specified by the host, a sysfs
160 attribute called 'name' will be populated with a name for
161 the port which can be used by udev scripts to create a
162 symlink to the device.
165 tristate "IBM POWER Barrier Synchronization Register support"
166 depends on PPC_PSERIES
168 This devices exposes a hardware mechanism for fast synchronization
169 of threads across a large system which avoids bouncing a cacheline
170 between several cores on a system
172 source "drivers/char/ipmi/Kconfig"
175 tristate "NetWinder thermometer support"
176 depends on ARCH_NETWINDER
178 Say Y here to include support for the thermal management hardware
179 found in the NetWinder. This driver allows the user to control the
180 temperature set points and to read the current temperature.
182 It is also possible to say M here to build it as a module (ds1620)
183 It is recommended to be used on a NetWinder, but it is not a
187 tristate "NetWinder Button"
188 depends on ARCH_NETWINDER
190 If you say Y here and create a character device node /dev/nwbutton
191 with major and minor numbers 10 and 158 ("man mknod"), then every
192 time the orange button is pressed a number of times, the number of
193 times the button was pressed will be written to that device.
195 This is most useful for applications, as yet unwritten, which
196 perform actions based on how many times the button is pressed in a
199 Do not hold the button down for too long, as the driver does not
200 alter the behaviour of the hardware reset circuitry attached to the
201 button; it will still execute a hard reset if the button is held
202 down for longer than approximately five seconds.
204 To compile this driver as a module, choose M here: the
205 module will be called nwbutton.
207 Most people will answer Y to this question and "Reboot Using Button"
208 below to be able to initiate a system shutdown from the button.
210 config NWBUTTON_REBOOT
211 bool "Reboot Using Button"
214 If you say Y here, then you will be able to initiate a system
215 shutdown and reboot by pressing the orange button a number of times.
216 The number of presses to initiate the shutdown is two by default,
217 but this can be altered by modifying the value of NUM_PRESSES_REBOOT
218 in nwbutton.h and recompiling the driver or, if you compile the
219 driver as a module, you can specify the number of presses at load
220 time with "insmod button reboot_count=<something>".
223 tristate "NetWinder flash support"
224 depends on ARCH_NETWINDER
226 If you say Y here and create a character device /dev/flash with
227 major 10 and minor 160 you can manipulate the flash ROM containing
228 the NetWinder firmware. Be careful as accidentally overwriting the
229 flash contents can render your computer unbootable. On no account
230 allow random users access to this device. :-)
232 To compile this driver as a module, choose M here: the
233 module will be called nwflash.
235 If you're not sure, say N.
237 source "drivers/char/hw_random/Kconfig"
240 tristate "/dev/nvram support"
241 depends on ATARI || X86 || (ARM && RTC_DRV_CMOS) || GENERIC_NVRAM
243 If you say Y here and create a character special file /dev/nvram
244 with major number 10 and minor number 144 using mknod ("man mknod"),
245 you get read and write access to the extra bytes of non-volatile
246 memory in the real time clock (RTC), which is contained in every PC
247 and most Ataris. The actual number of bytes varies, depending on the
248 nvram in the system, but is usually 114 (128-14 for the RTC).
250 This memory is conventionally called "CMOS RAM" on PCs and "NVRAM"
251 on Ataris. /dev/nvram may be used to view settings there, or to
252 change them (with some utility). It could also be used to frequently
253 save a few bits of very important data that may not be lost over
254 power-off and for which writing to disk is too insecure. Note
255 however that most NVRAM space in a PC belongs to the BIOS and you
256 should NEVER idly tamper with it. See Ralf Brown's interrupt list
257 for a guide to the use of CMOS bytes by your BIOS.
259 On Atari machines, /dev/nvram is always configured and does not need
262 To compile this driver as a module, choose M here: the
263 module will be called nvram.
266 # These legacy RTC drivers just cause too many conflicts with the generic
267 # RTC framework ... let's not even try to coexist any more.
272 tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
273 depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
274 && !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN && !UML
276 If you say Y here and create a character special file /dev/rtc with
277 major number 10 and minor number 135 using mknod ("man mknod"), you
278 will get access to the real time clock (or hardware clock) built
281 Every PC has such a clock built in. It can be used to generate
282 signals from as low as 1Hz up to 8192Hz, and can also be used
283 as a 24 hour alarm. It reports status information via the file
284 /proc/driver/rtc and its behaviour is set by various ioctls on
287 If you run Linux on a multiprocessor machine and said Y to
288 "Symmetric Multi Processing" above, you should say Y here to read
289 and set the RTC in an SMP compatible fashion.
291 If you think you have a use for such a device (such as periodic data
292 sampling), then say Y here, and read <file:Documentation/rtc.txt>
295 To compile this driver as a module, choose M here: the
296 module will be called rtc.
299 tristate "Enhanced Real Time Clock Support"
300 depends on SPARC32 && PCI
302 If you say Y here and create a character special file /dev/rtc with
303 major number 10 and minor number 135 using mknod ("man mknod"), you
304 will get access to the real time clock (or hardware clock) built
307 Every PC has such a clock built in. It can be used to generate
308 signals from as low as 1Hz up to 8192Hz, and can also be used
309 as a 24 hour alarm. It reports status information via the file
310 /proc/driver/rtc and its behaviour is set by various ioctls on
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 js-rtc.
321 tristate "Generic /dev/rtc emulation"
322 depends on RTC!=y && !IA64 && !ARM && !M32R && !MIPS && !SPARC && !FRV && !S390 && !SUPERH && !AVR32 && !BLACKFIN && !UML
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 It reports status information via the file /proc/driver/rtc and its
330 behaviour is set by various ioctls on /dev/rtc. If you enable the
331 "extended RTC operation" below it will also provide an emulation
332 for RTC_UIE which is required by some programs and may improve
333 precision in some cases.
335 To compile this driver as a module, choose M here: the
336 module will be called genrtc.
339 bool "Extended RTC operation"
342 Provides an emulation for RTC_UIE which is required by some programs
343 and may improve precision of the generic RTC support in some cases.
346 bool "EFI Real Time Clock Services"
350 tristate "DS1302 RTC support"
351 depends on M32R && (PLAT_M32700UT || PLAT_OPSPUT)
353 If you say Y here and create a character special file /dev/rtc with
354 major number 121 and minor number 0 using mknod ("man mknod"), you
355 will get access to the real time clock (or hardware clock) built
361 tristate "Double Talk PC internal speech card support"
364 This driver is for the DoubleTalk PC, a speech synthesizer
365 manufactured by RC Systems (<http://www.rcsys.com/>). It is also
366 called the `internal DoubleTalk'.
368 To compile this driver as a module, choose M here: the
369 module will be called dtlk.
372 tristate "Xilinx HWICAP Support"
373 depends on XILINX_VIRTEX || MICROBLAZE
375 This option enables support for Xilinx Internal Configuration
376 Access Port (ICAP) driver. The ICAP is used on Xilinx Virtex
377 FPGA platforms to partially reconfigure the FPGA at runtime.
382 tristate "Siemens R3964 line discipline"
385 This driver allows synchronous communication with devices using the
386 Siemens R3964 packet protocol. Unless you are dealing with special
387 hardware like PLCs, you are unlikely to need this.
389 To compile this driver as a module, choose M here: the
390 module will be called n_r3964.
395 tristate "Applicom intelligent fieldbus card support"
398 This driver provides the kernel-side support for the intelligent
399 fieldbus cards made by Applicom International. More information
400 about these cards can be found on the WWW at the address
401 <http://www.applicom-int.com/>, or by email from David Woodhouse
402 <dwmw2@infradead.org>.
404 To compile this driver as a module, choose M here: the
405 module will be called applicom.
410 tristate "Sony Vaio Programmable I/O Control Device support"
411 depends on X86 && PCI && INPUT && !64BIT
413 This driver enables access to the Sony Programmable I/O Control
414 Device which can be found in many (all ?) Sony Vaio laptops.
416 If you have one of those laptops, read
417 <file:Documentation/laptops/sonypi.txt>, and say Y or M here.
419 To compile this driver as a module, choose M here: the
420 module will be called sonypi.
423 tristate "TANBAC TB0219 GPIO support"
424 depends on TANBAC_TB022X
427 source "drivers/char/pcmcia/Kconfig"
430 tristate "ACP Modem (Mwave) support"
431 depends on X86 && TTY
434 The ACP modem (Mwave) for Linux is a WinModem. It is composed of a
435 kernel driver and a user level application. Together these components
436 support direct attachment to public switched telephone networks (PSTNs)
437 and support selected world wide countries.
439 This version of the ACP Modem driver supports the IBM Thinkpad 600E,
440 600, and 770 that include on board ACP modem hardware.
442 The modem also supports the standard communications port interface
443 (ttySx) and is compatible with the Hayes AT Command Set.
445 The user level application needed to use this driver can be found at
446 the IBM Linux Technology Center (LTC) web site:
447 <http://www.ibm.com/linux/ltc/>.
449 If you own one of the above IBM Thinkpads which has the Mwave chipset
452 To compile this driver as a module, choose M here: the
453 module will be called mwave.
456 tristate "NatSemi SCx200 GPIO Support"
460 Give userspace access to the GPIO pins on the National
461 Semiconductor SCx200 processors.
463 If compiled as a module, it will be called scx200_gpio.
466 tristate "NatSemi PC8736x GPIO Support"
467 depends on X86_32 && !UML
468 default SCx200_GPIO # mostly N
469 select NSC_GPIO # needed for support routines
471 Give userspace access to the GPIO pins on the National
472 Semiconductor PC-8736x (x=[03456]) SuperIO chip. The chip
473 has multiple functional units, inc several managed by
474 hwmon/pc87360 driver. Tested with PC-87366
476 If compiled as a module, it will be called pc8736x_gpio.
479 tristate "NatSemi Base GPIO Support"
481 # selected by SCx200_GPIO and PC8736x_GPIO
482 # what about 2 selectors differing: m != y
484 Common support used (and needed) by scx200_gpio and
485 pc8736x_gpio drivers. If those drivers are built as
486 modules, this one will be too, named nsc_gpio
489 tristate "RAW driver (/dev/raw/rawN)"
492 The raw driver permits block devices to be bound to /dev/raw/rawN.
493 Once bound, I/O against /dev/raw/rawN uses efficient zero-copy I/O.
494 See the raw(8) manpage for more details.
496 Applications should preferably open the device (eg /dev/hda1)
497 with the O_DIRECT flag.
500 int "Maximum number of RAW devices to support (1-65536)"
501 depends on RAW_DRIVER
504 The maximum number of RAW devices that are supported.
505 Default is 256. Increase this number in case you need lots of
509 bool "HPET - High Precision Event Timer" if (X86 || IA64)
513 If you say Y here, you will have a miscdevice named "/dev/hpet/". Each
514 open selects one of the timers supported by the HPET. The timers are
515 non-periodic and/or periodic.
518 bool "Allow mmap of HPET"
522 If you say Y here, user applications will be able to mmap
525 config HPET_MMAP_DEFAULT
526 bool "Enable HPET MMAP access by default"
530 In some hardware implementations, the page containing HPET
531 registers may also contain other things that shouldn't be
532 exposed to the user. This option selects the default (if
533 kernel parameter hpet_mmap is not set) user access to the
534 registers for applications that require it.
536 config HANGCHECK_TIMER
537 tristate "Hangcheck timer"
538 depends on X86 || IA64 || PPC64 || S390
540 The hangcheck-timer module detects when the system has gone
541 out to lunch past a certain margin. It can reboot the system
542 or merely print a warning.
545 tristate "MMTIMER Memory mapped RTC for SGI Altix"
546 depends on IA64_GENERIC || IA64_SGI_SN2
549 The mmtimer device allows direct userspace access to the
553 tristate "UV_MMTIMER Memory mapped RTC for SGI UV"
557 The uv_mmtimer device allows direct userspace access to the
560 source "drivers/char/tpm/Kconfig"
563 tristate "Telecom clock driver for ATCA SBC"
567 The telecom clock device is specific to the MPCBL0010 and MPCBL0050
568 ATCA computers and allows direct userspace access to the
569 configuration of the telecom clock configuration settings. This
570 device is used for hardware synchronization across the ATCA backplane
571 fabric. Upon loading, the driver exports a sysfs directory,
572 /sys/devices/platform/telco_clock, with a number of files for
573 controlling the behavior of this hardware.
578 depends on ISA || PCI
581 source "drivers/s390/char/Kconfig"
584 bool "Enable device interface for some SMD packet ports"
588 Enables userspace clients to read and write to some packet SMD
589 ports via device interface for MSM chipset.
592 bool "Character-device access via hypervisor to the Tilera SPI ROM"
596 This device provides character-level read-write access
597 to the SROM, typically via the "0", "1", and "2" devices
598 in /dev/srom/. The Tilera hypervisor makes the flash
599 device appear much like a simple EEPROM, and knows
600 how to partition a single ROM for multiple purposes.