1# SPDX-License-Identifier: GPL-2.0 2# 3# Character device configuration 4# 5 6menu "Character devices" 7 8source "drivers/tty/Kconfig" 9 10config TTY_PRINTK 11 tristate "TTY driver to output user messages via printk" 12 depends on EXPERT && TTY 13 default n 14 help 15 If you say Y here, the support for writing user messages (i.e. 16 console messages) via printk is available. 17 18 The feature is useful to inline user messages with kernel 19 messages. 20 In order to use this feature, you should output user messages 21 to /dev/ttyprintk or redirect console to this TTY, or boot 22 the kernel with console=ttyprintk. 23 24 If unsure, say N. 25 26config TTY_PRINTK_LEVEL 27 depends on TTY_PRINTK 28 int "ttyprintk log level (1-7)" 29 range 1 7 30 default "6" 31 help 32 Printk log level to use for ttyprintk messages. 33 34config PRINTER 35 tristate "Parallel printer support" 36 depends on PARPORT 37 help 38 If you intend to attach a printer to the parallel port of your Linux 39 box (as opposed to using a serial printer; if the connector at the 40 printer has 9 or 25 holes ["female"], then it's serial), say Y. 41 Also read the Printing-HOWTO, available from 42 <https://www.tldp.org/docs.html#howto>. 43 44 It is possible to share one parallel port among several devices 45 (e.g. printer and ZIP drive) and it is safe to compile the 46 corresponding drivers into the kernel. 47 48 To compile this driver as a module, choose M here and read 49 <file:Documentation/admin-guide/parport.rst>. The module will be called lp. 50 51 If you have several parallel ports, you can specify which ports to 52 use with the "lp" kernel command line option. (Try "man bootparam" 53 or see the documentation of your boot loader (lilo or loadlin) about 54 how to pass options to the kernel at boot time.) The syntax of the 55 "lp" command line option can be found in <file:drivers/char/lp.c>. 56 57 If you have more than 8 printers, you need to increase the LP_NO 58 macro in lp.c and the PARPORT_MAX macro in parport.h. 59 60config LP_CONSOLE 61 bool "Support for console on line printer" 62 depends on PRINTER 63 help 64 If you want kernel messages to be printed out as they occur, you 65 can have a console on the printer. This option adds support for 66 doing that; to actually get it to happen you need to pass the 67 option "console=lp0" to the kernel at boot time. 68 69 If the printer is out of paper (or off, or unplugged, or too 70 busy..) the kernel will stall until the printer is ready again. 71 By defining CONSOLE_LP_STRICT to 0 (at your own risk) you 72 can make the kernel continue when this happens, 73 but it'll lose the kernel messages. 74 75 If unsure, say N. 76 77config PPDEV 78 tristate "Support for user-space parallel port device drivers" 79 depends on PARPORT 80 help 81 Saying Y to this adds support for /dev/parport device nodes. This 82 is needed for programs that want portable access to the parallel 83 port, for instance deviceid (which displays Plug-and-Play device 84 IDs). 85 86 This is the parallel port equivalent of SCSI generic support (sg). 87 It is safe to say N to this -- it is not needed for normal printing 88 or parallel port CD-ROM/disk support. 89 90 To compile this driver as a module, choose M here: the 91 module will be called ppdev. 92 93 If unsure, say N. 94 95config VIRTIO_CONSOLE 96 tristate "Virtio console" 97 depends on TTY 98 select HVC_DRIVER 99 select VIRTIO 100 help 101 Virtio console for use with hypervisors. 102 103 Also serves as a general-purpose serial device for data 104 transfer between the guest and host. Character devices at 105 /dev/vportNpn will be created when corresponding ports are 106 found, where N is the device number and n is the port number 107 within that device. If specified by the host, a sysfs 108 attribute called 'name' will be populated with a name for 109 the port which can be used by udev scripts to create a 110 symlink to the device. 111 112config IBM_BSR 113 tristate "IBM POWER Barrier Synchronization Register support" 114 depends on PPC_PSERIES 115 help 116 This devices exposes a hardware mechanism for fast synchronization 117 of threads across a large system which avoids bouncing a cacheline 118 between several cores on a system 119 120config POWERNV_OP_PANEL 121 tristate "IBM POWERNV Operator Panel Display support" 122 depends on PPC_POWERNV 123 default m 124 help 125 If you say Y here, a special character device node, /dev/op_panel, 126 will be created which exposes the operator panel display on IBM 127 Power Systems machines with FSPs. 128 129 If you don't require access to the operator panel display from user 130 space, say N. 131 132 If unsure, say M here to build it as a module called powernv-op-panel. 133 134source "drivers/char/ipmi/Kconfig" 135 136config DS1620 137 tristate "NetWinder thermometer support" 138 depends on ARCH_NETWINDER 139 help 140 Say Y here to include support for the thermal management hardware 141 found in the NetWinder. This driver allows the user to control the 142 temperature set points and to read the current temperature. 143 144 It is also possible to say M here to build it as a module (ds1620) 145 It is recommended to be used on a NetWinder, but it is not a 146 necessity. 147 148config NWBUTTON 149 tristate "NetWinder Button" 150 depends on ARCH_NETWINDER 151 help 152 If you say Y here and create a character device node /dev/nwbutton 153 with major and minor numbers 10 and 158 ("man mknod"), then every 154 time the orange button is pressed a number of times, the number of 155 times the button was pressed will be written to that device. 156 157 This is most useful for applications, as yet unwritten, which 158 perform actions based on how many times the button is pressed in a 159 row. 160 161 Do not hold the button down for too long, as the driver does not 162 alter the behaviour of the hardware reset circuitry attached to the 163 button; it will still execute a hard reset if the button is held 164 down for longer than approximately five seconds. 165 166 To compile this driver as a module, choose M here: the 167 module will be called nwbutton. 168 169 Most people will answer Y to this question and "Reboot Using Button" 170 below to be able to initiate a system shutdown from the button. 171 172config NWBUTTON_REBOOT 173 bool "Reboot Using Button" 174 depends on NWBUTTON 175 help 176 If you say Y here, then you will be able to initiate a system 177 shutdown and reboot by pressing the orange button a number of times. 178 The number of presses to initiate the shutdown is two by default, 179 but this can be altered by modifying the value of NUM_PRESSES_REBOOT 180 in nwbutton.h and recompiling the driver or, if you compile the 181 driver as a module, you can specify the number of presses at load 182 time with "insmod button reboot_count=<something>". 183 184config NWFLASH 185 tristate "NetWinder flash support" 186 depends on ARCH_NETWINDER 187 help 188 If you say Y here and create a character device /dev/flash with 189 major 10 and minor 160 you can manipulate the flash ROM containing 190 the NetWinder firmware. Be careful as accidentally overwriting the 191 flash contents can render your computer unbootable. On no account 192 allow random users access to this device. :-) 193 194 To compile this driver as a module, choose M here: the 195 module will be called nwflash. 196 197 If you're not sure, say N. 198 199source "drivers/char/hw_random/Kconfig" 200 201config DTLK 202 tristate "Double Talk PC internal speech card support" 203 depends on ISA 204 help 205 This driver is for the DoubleTalk PC, a speech synthesizer 206 manufactured by RC Systems (<https://www.rcsys.com/>). It is also 207 called the `internal DoubleTalk'. 208 209 To compile this driver as a module, choose M here: the 210 module will be called dtlk. 211 212config XILINX_HWICAP 213 tristate "Xilinx HWICAP Support" 214 depends on MICROBLAZE 215 help 216 This option enables support for Xilinx Internal Configuration 217 Access Port (ICAP) driver. The ICAP is used on Xilinx Virtex 218 FPGA platforms to partially reconfigure the FPGA at runtime. 219 220 If unsure, say N. 221 222config APPLICOM 223 tristate "Applicom intelligent fieldbus card support" 224 depends on PCI 225 help 226 This driver provides the kernel-side support for the intelligent 227 fieldbus cards made by Applicom International. More information 228 about these cards can be found on the WWW at the address 229 <https://www.applicom-int.com/>, or by email from David Woodhouse 230 <dwmw2@infradead.org>. 231 232 To compile this driver as a module, choose M here: the 233 module will be called applicom. 234 235 If unsure, say N. 236 237config SONYPI 238 tristate "Sony Vaio Programmable I/O Control Device support" 239 depends on X86_32 && PCI && INPUT 240 help 241 This driver enables access to the Sony Programmable I/O Control 242 Device which can be found in many (all ?) Sony Vaio laptops. 243 244 If you have one of those laptops, read 245 <file:Documentation/admin-guide/laptops/sonypi.rst>, and say Y or M here. 246 247 To compile this driver as a module, choose M here: the 248 module will be called sonypi. 249 250config MWAVE 251 tristate "ACP Modem (Mwave) support" 252 depends on X86 && TTY 253 select SERIAL_8250 254 help 255 The ACP modem (Mwave) for Linux is a WinModem. It is composed of a 256 kernel driver and a user level application. Together these components 257 support direct attachment to public switched telephone networks (PSTNs) 258 and support selected world wide countries. 259 260 This version of the ACP Modem driver supports the IBM Thinkpad 600E, 261 600, and 770 that include on board ACP modem hardware. 262 263 The modem also supports the standard communications port interface 264 (ttySx) and is compatible with the Hayes AT Command Set. 265 266 The user level application needed to use this driver can be found at 267 the IBM Linux Technology Center (LTC) web site: 268 <http://www.ibm.com/linux/ltc/>. 269 270 If you own one of the above IBM Thinkpads which has the Mwave chipset 271 in it, say Y. 272 273 To compile this driver as a module, choose M here: the 274 module will be called mwave. 275 276config SCx200_GPIO 277 tristate "NatSemi SCx200 GPIO Support" 278 depends on SCx200 279 select NSC_GPIO 280 help 281 Give userspace access to the GPIO pins on the National 282 Semiconductor SCx200 processors. 283 284 If compiled as a module, it will be called scx200_gpio. 285 286config PC8736x_GPIO 287 tristate "NatSemi PC8736x GPIO Support" 288 depends on X86_32 && !UML 289 default SCx200_GPIO # mostly N 290 select NSC_GPIO # needed for support routines 291 help 292 Give userspace access to the GPIO pins on the National 293 Semiconductor PC-8736x (x=[03456]) SuperIO chip. The chip 294 has multiple functional units, inc several managed by 295 hwmon/pc87360 driver. Tested with PC-87366 296 297 If compiled as a module, it will be called pc8736x_gpio. 298 299config NSC_GPIO 300 tristate "NatSemi Base GPIO Support" 301 depends on X86_32 302 # selected by SCx200_GPIO and PC8736x_GPIO 303 # what about 2 selectors differing: m != y 304 help 305 Common support used (and needed) by scx200_gpio and 306 pc8736x_gpio drivers. If those drivers are built as 307 modules, this one will be too, named nsc_gpio 308 309config DEVMEM 310 bool "/dev/mem virtual device support" 311 default y 312 help 313 Say Y here if you want to support the /dev/mem device. 314 The /dev/mem device is used to access areas of physical 315 memory. 316 When in doubt, say "Y". 317 318config NVRAM 319 tristate "/dev/nvram support" 320 depends on X86 || HAVE_ARCH_NVRAM_OPS 321 default M68K || PPC 322 help 323 If you say Y here and create a character special file /dev/nvram 324 with major number 10 and minor number 144 using mknod ("man mknod"), 325 you get read and write access to the non-volatile memory. 326 327 /dev/nvram may be used to view settings in NVRAM or to change them 328 (with some utility). It could also be used to frequently 329 save a few bits of very important data that may not be lost over 330 power-off and for which writing to disk is too insecure. Note 331 however that most NVRAM space in a PC belongs to the BIOS and you 332 should NEVER idly tamper with it. See Ralf Brown's interrupt list 333 for a guide to the use of CMOS bytes by your BIOS. 334 335 This memory is conventionally called "NVRAM" on PowerPC machines, 336 "CMOS RAM" on PCs, "NVRAM" on Ataris and "PRAM" on Macintoshes. 337 338 To compile this driver as a module, choose M here: the 339 module will be called nvram. 340 341config DEVPORT 342 bool "/dev/port character device" 343 depends on ISA || PCI 344 default y 345 help 346 Say Y here if you want to support the /dev/port device. The /dev/port 347 device is similar to /dev/mem, but for I/O ports. 348 349config HPET 350 bool "HPET - High Precision Event Timer" if (X86 || IA64) 351 default n 352 depends on ACPI 353 help 354 If you say Y here, you will have a miscdevice named "/dev/hpet/". Each 355 open selects one of the timers supported by the HPET. The timers are 356 non-periodic and/or periodic. 357 358config HPET_MMAP 359 bool "Allow mmap of HPET" 360 default y 361 depends on HPET 362 help 363 If you say Y here, user applications will be able to mmap 364 the HPET registers. 365 366config HPET_MMAP_DEFAULT 367 bool "Enable HPET MMAP access by default" 368 default y 369 depends on HPET_MMAP 370 help 371 In some hardware implementations, the page containing HPET 372 registers may also contain other things that shouldn't be 373 exposed to the user. This option selects the default (if 374 kernel parameter hpet_mmap is not set) user access to the 375 registers for applications that require it. 376 377config HANGCHECK_TIMER 378 tristate "Hangcheck timer" 379 depends on X86 || IA64 || PPC64 || S390 380 help 381 The hangcheck-timer module detects when the system has gone 382 out to lunch past a certain margin. It can reboot the system 383 or merely print a warning. 384 385config UV_MMTIMER 386 tristate "UV_MMTIMER Memory mapped RTC for SGI UV" 387 depends on X86_UV 388 default m 389 help 390 The uv_mmtimer device allows direct userspace access to the 391 UV system timer. 392 393source "drivers/char/tpm/Kconfig" 394 395config TELCLOCK 396 tristate "Telecom clock driver for ATCA SBC" 397 depends on X86 398 default n 399 help 400 The telecom clock device is specific to the MPCBL0010 and MPCBL0050 401 ATCA computers and allows direct userspace access to the 402 configuration of the telecom clock configuration settings. This 403 device is used for hardware synchronization across the ATCA backplane 404 fabric. Upon loading, the driver exports a sysfs directory, 405 /sys/devices/platform/telco_clock, with a number of files for 406 controlling the behavior of this hardware. 407 408source "drivers/s390/char/Kconfig" 409 410source "drivers/char/xillybus/Kconfig" 411 412config ADI 413 tristate "SPARC Privileged ADI driver" 414 depends on SPARC64 415 default m 416 help 417 SPARC M7 and newer processors utilize ADI (Application Data 418 Integrity) to version and protect memory. This driver provides 419 read/write access to the ADI versions for privileged processes. 420 This feature is also known as MCD (Memory Corruption Detection) 421 and SSM (Silicon Secured Memory). Intended consumers of this 422 driver include crash and makedumpfile. 423 424endmenu 425