Kconfig 17 KB

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  1. # SPDX-License-Identifier: GPL-2.0
  2. #
  3. # Character device configuration
  4. #
  5. menu "Character devices"
  6. source "drivers/tty/Kconfig"
  7. config TTY_PRINTK
  8. tristate "TTY driver to output user messages via printk"
  9. depends on EXPERT && TTY
  10. default n
  11. help
  12. If you say Y here, the support for writing user messages (i.e.
  13. console messages) via printk is available.
  14. The feature is useful to inline user messages with kernel
  15. messages.
  16. In order to use this feature, you should output user messages
  17. to /dev/ttyprintk or redirect console to this TTY, or boot
  18. the kernel with console=ttyprintk.
  19. If unsure, say N.
  20. config TTY_PRINTK_LEVEL
  21. depends on TTY_PRINTK
  22. int "ttyprintk log level (1-7)"
  23. range 1 7
  24. default "6"
  25. help
  26. Printk log level to use for ttyprintk messages.
  27. config PRINTER
  28. tristate "Parallel printer support"
  29. depends on PARPORT
  30. help
  31. If you intend to attach a printer to the parallel port of your Linux
  32. box (as opposed to using a serial printer; if the connector at the
  33. printer has 9 or 25 holes ["female"], then it's serial), say Y.
  34. Also read the Printing-HOWTO, available from
  35. <https://www.tldp.org/docs.html#howto>.
  36. It is possible to share one parallel port among several devices
  37. (e.g. printer and ZIP drive) and it is safe to compile the
  38. corresponding drivers into the kernel.
  39. To compile this driver as a module, choose M here and read
  40. <file:Documentation/admin-guide/parport.rst>. The module will be called lp.
  41. If you have several parallel ports, you can specify which ports to
  42. use with the "lp" kernel command line option. (Try "man bootparam"
  43. or see the documentation of your boot loader (lilo or loadlin) about
  44. how to pass options to the kernel at boot time.) The syntax of the
  45. "lp" command line option can be found in <file:drivers/char/lp.c>.
  46. If you have more than 8 printers, you need to increase the LP_NO
  47. macro in lp.c and the PARPORT_MAX macro in parport.h.
  48. config LP_CONSOLE
  49. bool "Support for console on line printer"
  50. depends on PRINTER
  51. help
  52. If you want kernel messages to be printed out as they occur, you
  53. can have a console on the printer. This option adds support for
  54. doing that; to actually get it to happen you need to pass the
  55. option "console=lp0" to the kernel at boot time.
  56. If the printer is out of paper (or off, or unplugged, or too
  57. busy..) the kernel will stall until the printer is ready again.
  58. By defining CONSOLE_LP_STRICT to 0 (at your own risk) you
  59. can make the kernel continue when this happens,
  60. but it'll lose the kernel messages.
  61. If unsure, say N.
  62. config PPDEV
  63. tristate "Support for user-space parallel port device drivers"
  64. depends on PARPORT
  65. help
  66. Saying Y to this adds support for /dev/parport device nodes. This
  67. is needed for programs that want portable access to the parallel
  68. port, for instance deviceid (which displays Plug-and-Play device
  69. IDs).
  70. This is the parallel port equivalent of SCSI generic support (sg).
  71. It is safe to say N to this -- it is not needed for normal printing
  72. or parallel port CD-ROM/disk support.
  73. To compile this driver as a module, choose M here: the
  74. module will be called ppdev.
  75. If unsure, say N.
  76. config VIRTIO_CONSOLE
  77. tristate "Virtio console"
  78. depends on TTY
  79. select HVC_DRIVER
  80. select VIRTIO
  81. help
  82. Virtio console for use with hypervisors.
  83. Also serves as a general-purpose serial device for data
  84. transfer between the guest and host. Character devices at
  85. /dev/vportNpn will be created when corresponding ports are
  86. found, where N is the device number and n is the port number
  87. within that device. If specified by the host, a sysfs
  88. attribute called 'name' will be populated with a name for
  89. the port which can be used by udev scripts to create a
  90. symlink to the device.
  91. config IBM_BSR
  92. tristate "IBM POWER Barrier Synchronization Register support"
  93. depends on PPC_PSERIES
  94. help
  95. This devices exposes a hardware mechanism for fast synchronization
  96. of threads across a large system which avoids bouncing a cacheline
  97. between several cores on a system
  98. config POWERNV_OP_PANEL
  99. tristate "IBM POWERNV Operator Panel Display support"
  100. depends on PPC_POWERNV
  101. default m
  102. help
  103. If you say Y here, a special character device node, /dev/op_panel,
  104. will be created which exposes the operator panel display on IBM
  105. Power Systems machines with FSPs.
  106. If you don't require access to the operator panel display from user
  107. space, say N.
  108. If unsure, say M here to build it as a module called powernv-op-panel.
  109. source "drivers/char/ipmi/Kconfig"
  110. config DS1620
  111. tristate "NetWinder thermometer support"
  112. depends on ARCH_NETWINDER
  113. help
  114. Say Y here to include support for the thermal management hardware
  115. found in the NetWinder. This driver allows the user to control the
  116. temperature set points and to read the current temperature.
  117. It is also possible to say M here to build it as a module (ds1620)
  118. It is recommended to be used on a NetWinder, but it is not a
  119. necessity.
  120. config NWBUTTON
  121. tristate "NetWinder Button"
  122. depends on ARCH_NETWINDER
  123. help
  124. If you say Y here and create a character device node /dev/nwbutton
  125. with major and minor numbers 10 and 158 ("man mknod"), then every
  126. time the orange button is pressed a number of times, the number of
  127. times the button was pressed will be written to that device.
  128. This is most useful for applications, as yet unwritten, which
  129. perform actions based on how many times the button is pressed in a
  130. row.
  131. Do not hold the button down for too long, as the driver does not
  132. alter the behaviour of the hardware reset circuitry attached to the
  133. button; it will still execute a hard reset if the button is held
  134. down for longer than approximately five seconds.
  135. To compile this driver as a module, choose M here: the
  136. module will be called nwbutton.
  137. Most people will answer Y to this question and "Reboot Using Button"
  138. below to be able to initiate a system shutdown from the button.
  139. config NWBUTTON_REBOOT
  140. bool "Reboot Using Button"
  141. depends on NWBUTTON
  142. help
  143. If you say Y here, then you will be able to initiate a system
  144. shutdown and reboot by pressing the orange button a number of times.
  145. The number of presses to initiate the shutdown is two by default,
  146. but this can be altered by modifying the value of NUM_PRESSES_REBOOT
  147. in nwbutton.h and recompiling the driver or, if you compile the
  148. driver as a module, you can specify the number of presses at load
  149. time with "insmod button reboot_count=<something>".
  150. config NWFLASH
  151. tristate "NetWinder flash support"
  152. depends on ARCH_NETWINDER
  153. help
  154. If you say Y here and create a character device /dev/flash with
  155. major 10 and minor 160 you can manipulate the flash ROM containing
  156. the NetWinder firmware. Be careful as accidentally overwriting the
  157. flash contents can render your computer unbootable. On no account
  158. allow random users access to this device. :-)
  159. To compile this driver as a module, choose M here: the
  160. module will be called nwflash.
  161. If you're not sure, say N.
  162. source "drivers/char/hw_random/Kconfig"
  163. config DTLK
  164. tristate "Double Talk PC internal speech card support"
  165. depends on ISA
  166. help
  167. This driver is for the DoubleTalk PC, a speech synthesizer
  168. manufactured by RC Systems (<https://www.rcsys.com/>). It is also
  169. called the `internal DoubleTalk'.
  170. To compile this driver as a module, choose M here: the
  171. module will be called dtlk.
  172. config XILINX_HWICAP
  173. tristate "Xilinx HWICAP Support"
  174. depends on MICROBLAZE
  175. help
  176. This option enables support for Xilinx Internal Configuration
  177. Access Port (ICAP) driver. The ICAP is used on Xilinx Virtex
  178. FPGA platforms to partially reconfigure the FPGA at runtime.
  179. If unsure, say N.
  180. config APPLICOM
  181. tristate "Applicom intelligent fieldbus card support"
  182. depends on PCI
  183. help
  184. This driver provides the kernel-side support for the intelligent
  185. fieldbus cards made by Applicom International. More information
  186. about these cards can be found on the WWW at the address
  187. <https://www.applicom-int.com/>, or by email from David Woodhouse
  188. <[email protected]>.
  189. To compile this driver as a module, choose M here: the
  190. module will be called applicom.
  191. If unsure, say N.
  192. config SONYPI
  193. tristate "Sony Vaio Programmable I/O Control Device support"
  194. depends on X86_32 && PCI && INPUT
  195. help
  196. This driver enables access to the Sony Programmable I/O Control
  197. Device which can be found in many (all ?) Sony Vaio laptops.
  198. If you have one of those laptops, read
  199. <file:Documentation/admin-guide/laptops/sonypi.rst>, and say Y or M here.
  200. To compile this driver as a module, choose M here: the
  201. module will be called sonypi.
  202. source "drivers/char/pcmcia/Kconfig"
  203. config MWAVE
  204. tristate "ACP Modem (Mwave) support"
  205. depends on X86 && TTY
  206. select SERIAL_8250
  207. help
  208. The ACP modem (Mwave) for Linux is a WinModem. It is composed of a
  209. kernel driver and a user level application. Together these components
  210. support direct attachment to public switched telephone networks (PSTNs)
  211. and support selected world wide countries.
  212. This version of the ACP Modem driver supports the IBM Thinkpad 600E,
  213. 600, and 770 that include on board ACP modem hardware.
  214. The modem also supports the standard communications port interface
  215. (ttySx) and is compatible with the Hayes AT Command Set.
  216. The user level application needed to use this driver can be found at
  217. the IBM Linux Technology Center (LTC) web site:
  218. <http://www.ibm.com/linux/ltc/>.
  219. If you own one of the above IBM Thinkpads which has the Mwave chipset
  220. in it, say Y.
  221. To compile this driver as a module, choose M here: the
  222. module will be called mwave.
  223. config SCx200_GPIO
  224. tristate "NatSemi SCx200 GPIO Support"
  225. depends on SCx200
  226. select NSC_GPIO
  227. help
  228. Give userspace access to the GPIO pins on the National
  229. Semiconductor SCx200 processors.
  230. If compiled as a module, it will be called scx200_gpio.
  231. config PC8736x_GPIO
  232. tristate "NatSemi PC8736x GPIO Support"
  233. depends on X86_32 && !UML
  234. default SCx200_GPIO # mostly N
  235. select NSC_GPIO # needed for support routines
  236. help
  237. Give userspace access to the GPIO pins on the National
  238. Semiconductor PC-8736x (x=[03456]) SuperIO chip. The chip
  239. has multiple functional units, inc several managed by
  240. hwmon/pc87360 driver. Tested with PC-87366
  241. If compiled as a module, it will be called pc8736x_gpio.
  242. config NSC_GPIO
  243. tristate "NatSemi Base GPIO Support"
  244. depends on X86_32
  245. # selected by SCx200_GPIO and PC8736x_GPIO
  246. # what about 2 selectors differing: m != y
  247. help
  248. Common support used (and needed) by scx200_gpio and
  249. pc8736x_gpio drivers. If those drivers are built as
  250. modules, this one will be too, named nsc_gpio
  251. config DEVMEM
  252. bool "/dev/mem virtual device support"
  253. default y
  254. help
  255. Say Y here if you want to support the /dev/mem device.
  256. The /dev/mem device is used to access areas of physical
  257. memory.
  258. When in doubt, say "Y".
  259. config NVRAM
  260. tristate "/dev/nvram support"
  261. depends on X86 || HAVE_ARCH_NVRAM_OPS
  262. default M68K || PPC
  263. help
  264. If you say Y here and create a character special file /dev/nvram
  265. with major number 10 and minor number 144 using mknod ("man mknod"),
  266. you get read and write access to the non-volatile memory.
  267. /dev/nvram may be used to view settings in NVRAM or to change them
  268. (with some utility). It could also be used to frequently
  269. save a few bits of very important data that may not be lost over
  270. power-off and for which writing to disk is too insecure. Note
  271. however that most NVRAM space in a PC belongs to the BIOS and you
  272. should NEVER idly tamper with it. See Ralf Brown's interrupt list
  273. for a guide to the use of CMOS bytes by your BIOS.
  274. This memory is conventionally called "NVRAM" on PowerPC machines,
  275. "CMOS RAM" on PCs, "NVRAM" on Ataris and "PRAM" on Macintoshes.
  276. To compile this driver as a module, choose M here: the
  277. module will be called nvram.
  278. config DEVPORT
  279. bool "/dev/port character device"
  280. depends on ISA || PCI
  281. default y
  282. help
  283. Say Y here if you want to support the /dev/port device. The /dev/port
  284. device is similar to /dev/mem, but for I/O ports.
  285. config HPET
  286. bool "HPET - High Precision Event Timer" if (X86 || IA64)
  287. default n
  288. depends on ACPI
  289. help
  290. If you say Y here, you will have a miscdevice named "/dev/hpet/". Each
  291. open selects one of the timers supported by the HPET. The timers are
  292. non-periodic and/or periodic.
  293. config HPET_MMAP
  294. bool "Allow mmap of HPET"
  295. default y
  296. depends on HPET
  297. help
  298. If you say Y here, user applications will be able to mmap
  299. the HPET registers.
  300. config HPET_MMAP_DEFAULT
  301. bool "Enable HPET MMAP access by default"
  302. default y
  303. depends on HPET_MMAP
  304. help
  305. In some hardware implementations, the page containing HPET
  306. registers may also contain other things that shouldn't be
  307. exposed to the user. This option selects the default (if
  308. kernel parameter hpet_mmap is not set) user access to the
  309. registers for applications that require it.
  310. config HANGCHECK_TIMER
  311. tristate "Hangcheck timer"
  312. depends on X86 || IA64 || PPC64 || S390
  313. help
  314. The hangcheck-timer module detects when the system has gone
  315. out to lunch past a certain margin. It can reboot the system
  316. or merely print a warning.
  317. config UV_MMTIMER
  318. tristate "UV_MMTIMER Memory mapped RTC for SGI UV"
  319. depends on X86_UV
  320. default m
  321. help
  322. The uv_mmtimer device allows direct userspace access to the
  323. UV system timer.
  324. source "drivers/char/tpm/Kconfig"
  325. config TELCLOCK
  326. tristate "Telecom clock driver for ATCA SBC"
  327. depends on X86
  328. default n
  329. help
  330. The telecom clock device is specific to the MPCBL0010 and MPCBL0050
  331. ATCA computers and allows direct userspace access to the
  332. configuration of the telecom clock configuration settings. This
  333. device is used for hardware synchronization across the ATCA backplane
  334. fabric. Upon loading, the driver exports a sysfs directory,
  335. /sys/devices/platform/telco_clock, with a number of files for
  336. controlling the behavior of this hardware.
  337. source "drivers/s390/char/Kconfig"
  338. source "drivers/char/xillybus/Kconfig"
  339. config MSM_RDBG
  340. tristate "QTI Remote debug driver"
  341. help
  342. Implements a shared memory based transport mechanism that allows
  343. for a debugger running on a host PC to communicate with a remote
  344. stub running on peripheral subsystems such as the ADSP, MODEM etc.
  345. Say M if you want to enable this module.
  346. config ADI
  347. tristate "SPARC Privileged ADI driver"
  348. depends on SPARC64
  349. default m
  350. help
  351. SPARC M7 and newer processors utilize ADI (Application Data
  352. Integrity) to version and protect memory. This driver provides
  353. read/write access to the ADI versions for privileged processes.
  354. This feature is also known as MCD (Memory Corruption Detection)
  355. and SSM (Silicon Secured Memory). Intended consumers of this
  356. driver include crash and makedumpfile.
  357. config RANDOM_TRUST_CPU
  358. bool "Initialize RNG using CPU RNG instructions"
  359. default y
  360. help
  361. Initialize the RNG using random numbers supplied by the CPU's
  362. RNG instructions (e.g. RDRAND), if supported and available. These
  363. random numbers are never used directly, but are rather hashed into
  364. the main input pool, and this happens regardless of whether or not
  365. this option is enabled. Instead, this option controls whether the
  366. they are credited and hence can initialize the RNG. Additionally,
  367. other sources of randomness are always used, regardless of this
  368. setting. Enabling this implies trusting that the CPU can supply high
  369. quality and non-backdoored random numbers.
  370. Say Y here unless you have reason to mistrust your CPU or believe
  371. its RNG facilities may be faulty. This may also be configured at
  372. boot time with "random.trust_cpu=on/off".
  373. config RANDOM_TRUST_BOOTLOADER
  374. bool "Initialize RNG using bootloader-supplied seed"
  375. default y
  376. help
  377. Initialize the RNG using a seed supplied by the bootloader or boot
  378. environment (e.g. EFI or a bootloader-generated device tree). This
  379. seed is not used directly, but is rather hashed into the main input
  380. pool, and this happens regardless of whether or not this option is
  381. enabled. Instead, this option controls whether the seed is credited
  382. and hence can initialize the RNG. Additionally, other sources of
  383. randomness are always used, regardless of this setting. Enabling
  384. this implies trusting that the bootloader can supply high quality and
  385. non-backdoored seeds.
  386. Say Y here unless you have reason to mistrust your bootloader or
  387. believe its RNG facilities may be faulty. This may also be configured
  388. at boot time with "random.trust_bootloader=on/off".
  389. config VIRTIO_EAVB
  390. tristate "Virtio eavb driver"
  391. depends on VIRTIO
  392. help
  393. This the virtual eavb frontend driver based on virtio. Eavb
  394. means ethernet Audio Video Bridging. It provides unified ioctl
  395. interface for userspace. Say Y if you want to support virtual
  396. eavb.
  397. endmenu