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Diffstat (limited to 'drivers/tty/Kconfig')
| -rw-r--r-- | drivers/tty/Kconfig | 385 |
1 files changed, 385 insertions, 0 deletions
diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig new file mode 100644 index 000000000..cc30ff93e --- /dev/null +++ b/drivers/tty/Kconfig @@ -0,0 +1,385 @@ +# SPDX-License-Identifier: GPL-2.0 +config TTY + bool "Enable TTY" if EXPERT + default y + help + Allows you to remove TTY support which can save space, and + blocks features that require TTY from inclusion in the kernel. + TTY is required for any text terminals or serial port + communication. Most users should leave this enabled. + +if TTY + +config VT + bool "Virtual terminal" if EXPERT + select INPUT + default y if !UML + help + If you say Y here, you will get support for terminal devices with + display and keyboard devices. These are called "virtual" because you + can run several virtual terminals (also called virtual consoles) on + one physical terminal. This is rather useful, for example one + virtual terminal can collect system messages and warnings, another + one can be used for a text-mode user session, and a third could run + an X session, all in parallel. Switching between virtual terminals + is done with certain key combinations, usually Alt-<function key>. + + The setterm command ("man setterm") can be used to change the + properties (such as colors or beeping) of a virtual terminal. The + man page console_codes(4) ("man console_codes") contains the special + character sequences that can be used to change those properties + directly. The fonts used on virtual terminals can be changed with + the setfont ("man setfont") command and the key bindings are defined + with the loadkeys ("man loadkeys") command. + + You need at least one virtual terminal device in order to make use + of your keyboard and monitor. Therefore, only people configuring an + embedded system would want to say N here in order to save some + memory; the only way to log into such a system is then via a serial + or network connection. + + If unsure, say Y, or else you won't be able to do much with your new + shiny Linux system :-) + +config CONSOLE_TRANSLATIONS + depends on VT + default y + bool "Enable character translations in console" if EXPERT + help + This enables support for font mapping and Unicode translation + on virtual consoles. + +config VT_CONSOLE + bool "Support for console on virtual terminal" if EXPERT + depends on VT + default y + help + The system console is the device which receives all kernel messages + and warnings and which allows logins in single user mode. If you + answer Y here, a virtual terminal (the device used to interact with + a physical terminal) can be used as system console. This is the most + common mode of operations, so you should say Y here unless you want + the kernel messages be output only to a serial port (in which case + you should say Y to "Console on serial port", below). + + If you do say Y here, by default the currently visible virtual + terminal (/dev/tty0) will be used as system console. You can change + that with a kernel command line option such as "console=tty3" which + would use the third virtual terminal as system console. (Try "man + bootparam" or see the documentation of your boot loader (lilo or + loadlin) about how to pass options to the kernel at boot time.) + + If unsure, say Y. + +config VT_CONSOLE_SLEEP + def_bool y + depends on VT_CONSOLE && PM_SLEEP + +config HW_CONSOLE + bool + depends on VT + default y + +config VT_HW_CONSOLE_BINDING + bool "Support for binding and unbinding console drivers" + depends on HW_CONSOLE + help + The virtual terminal is the device that interacts with the physical + terminal through console drivers. On these systems, at least one + console driver is loaded. In other configurations, additional console + drivers may be enabled, such as the framebuffer console. If more than + 1 console driver is enabled, setting this to 'y' will allow you to + select the console driver that will serve as the backend for the + virtual terminals. + + See <file:Documentation/driver-api/console.rst> for more + information. For framebuffer console users, please refer to + <file:Documentation/fb/fbcon.rst>. + +config UNIX98_PTYS + bool "Unix98 PTY support" if EXPERT + default y + help + A pseudo terminal (PTY) is a software device consisting of two + halves: a master and a slave. The slave device behaves identical to + a physical terminal; the master device is used by a process to + read data from and write data to the slave, thereby emulating a + terminal. Typical programs for the master side are telnet servers + and xterms. + + Linux has traditionally used the BSD-like names /dev/ptyxx for + masters and /dev/ttyxx for slaves of pseudo terminals. This scheme + has a number of problems. The GNU C library glibc 2.1 and later, + however, supports the Unix98 naming standard: in order to acquire a + pseudo terminal, a process opens /dev/ptmx; the number of the pseudo + terminal is then made available to the process and the pseudo + terminal slave can be accessed as /dev/pts/<number>. What was + traditionally /dev/ttyp2 will then be /dev/pts/2, for example. + + All modern Linux systems use the Unix98 ptys. Say Y unless + you're on an embedded system and want to conserve memory. + +config LEGACY_PTYS + bool "Legacy (BSD) PTY support" + default y + help + A pseudo terminal (PTY) is a software device consisting of two + halves: a master and a slave. The slave device behaves identical to + a physical terminal; the master device is used by a process to + read data from and write data to the slave, thereby emulating a + terminal. Typical programs for the master side are telnet servers + and xterms. + + Linux has traditionally used the BSD-like names /dev/ptyxx + for masters and /dev/ttyxx for slaves of pseudo + terminals. This scheme has a number of problems, including + security. This option enables these legacy devices; on most + systems, it is safe to say N. + +config LEGACY_PTY_COUNT + int "Maximum number of legacy PTY in use" + depends on LEGACY_PTYS + range 0 256 + default "256" + help + The maximum number of legacy PTYs that can be used at any one time. + The default is 256, and should be more than enough. Embedded + systems may want to reduce this to save memory. + + When not in use, each legacy PTY occupies 12 bytes on 32-bit + architectures and 24 bytes on 64-bit architectures. + +config LDISC_AUTOLOAD + bool "Automatically load TTY Line Disciplines" + default y + help + Historically the kernel has always automatically loaded any + line discipline that is in a kernel module when a user asks + for it to be loaded with the TIOCSETD ioctl, or through other + means. This is not always the best thing to do on systems + where you know you will not be using some of the more + "ancient" line disciplines, so prevent the kernel from doing + this unless the request is coming from a process with the + CAP_SYS_MODULE permissions. + + Say 'Y' here if you trust your userspace users to do the right + thing, or if you have only provided the line disciplines that + you know you will be using, or if you wish to continue to use + the traditional method of on-demand loading of these modules + by any user. + + This functionality can be changed at runtime with the + dev.tty.ldisc_autoload sysctl, this configuration option will + only set the default value of this functionality. + +source "drivers/tty/serial/Kconfig" + +config SERIAL_NONSTANDARD + bool "Non-standard serial port support" + depends on HAS_IOMEM + help + Say Y here if you have any non-standard serial boards -- boards + which aren't supported using the standard "dumb" serial driver. + This includes intelligent serial boards such as + Digiboards, etc. These are usually used for systems that need many + serial ports because they serve many terminals or dial-in + connections. + + Note that the answer to this question won't directly affect the + kernel: saying N will just cause the configurator to skip all + the questions about non-standard serial boards. + + Most people can say N here. + +config MOXA_INTELLIO + tristate "Moxa Intellio support" + depends on SERIAL_NONSTANDARD && (ISA || EISA || PCI) + select FW_LOADER + help + Say Y here if you have a Moxa Intellio multiport serial card. + + To compile this driver as a module, choose M here: the + module will be called moxa. + +config MOXA_SMARTIO + tristate "Moxa SmartIO support v. 2.0" + depends on SERIAL_NONSTANDARD && PCI + help + Say Y here if you have a Moxa SmartIO multiport serial card and/or + want to help develop a new version of this driver. + + This is upgraded (1.9.1) driver from original Moxa drivers with + changes finally resulting in PCI probing. + + This driver can also be built as a module. The module will be called + mxser. If you want to do that, say M here. + +config SYNCLINK_GT + tristate "SyncLink GT/AC support" + depends on SERIAL_NONSTANDARD && PCI + help + Support for SyncLink GT and SyncLink AC families of + synchronous and asynchronous serial adapters + manufactured by Microgate Systems, Ltd. (www.microgate.com) + +config N_HDLC + tristate "HDLC line discipline support" + depends on SERIAL_NONSTANDARD + help + Allows synchronous HDLC communications with tty device drivers that + support synchronous HDLC such as the Microgate SyncLink adapter. + + This driver can be built as a module ( = code which can be + inserted in and removed from the running kernel whenever you want). + The module will be called n_hdlc. If you want to do that, say M + here. + +config PPC_EPAPR_HV_BYTECHAN + bool "ePAPR hypervisor byte channel driver" + depends on PPC + select EPAPR_PARAVIRT + help + This driver creates /dev entries for each ePAPR hypervisor byte + channel, thereby allowing applications to communicate with byte + channels as if they were serial ports. + +config PPC_EARLY_DEBUG_EHV_BC + bool "Early console (udbg) support for ePAPR hypervisors" + depends on PPC_EPAPR_HV_BYTECHAN=y + help + Select this option to enable early console (a.k.a. "udbg") support + via an ePAPR byte channel. You also need to choose the byte channel + handle below. + +config PPC_EARLY_DEBUG_EHV_BC_HANDLE + int "Byte channel handle for early console (udbg)" + depends on PPC_EARLY_DEBUG_EHV_BC + default 0 + help + If you want early console (udbg) output through a byte channel, + specify the handle of the byte channel to use. + + For this to work, the byte channel driver must be compiled + in-kernel, not as a module. + + Note that only one early console driver can be enabled, so don't + enable any others if you enable this one. + + If the number you specify is not a valid byte channel handle, then + there simply will be no early console output. This is true also + if you don't boot under a hypervisor at all. + +config GOLDFISH_TTY + tristate "Goldfish TTY Driver" + depends on GOLDFISH + select SERIAL_CORE + select SERIAL_CORE_CONSOLE + help + Console and system TTY driver for the Goldfish virtual platform. + +config GOLDFISH_TTY_EARLY_CONSOLE + bool + default y if GOLDFISH_TTY=y + select SERIAL_EARLYCON + +config N_GSM + tristate "GSM MUX line discipline support (EXPERIMENTAL)" + depends on NET + help + This line discipline provides support for the GSM MUX protocol and + presents the mux as a set of 61 individual tty devices. + +config NOZOMI + tristate "HSDPA Broadband Wireless Data Card - Globe Trotter" + depends on PCI + help + If you have a HSDPA driver Broadband Wireless Data Card - + Globe Trotter PCMCIA card, say Y here. + + To compile this driver as a module, choose M here, the module + will be called nozomi. + +config MIPS_EJTAG_FDC_TTY + bool "MIPS EJTAG Fast Debug Channel TTY" + depends on MIPS_CDMM + help + This enables a TTY and console on the MIPS EJTAG Fast Debug Channels, + if they are present. This can be useful when working with an EJTAG + probe which supports it, to get console output and a login prompt via + EJTAG without needing to connect a serial cable. + + TTY devices are named e.g. ttyFDC3c2 (for FDC channel 2 of the FDC on + CPU3). + + The console can be enabled with console=fdc1 (for FDC channel 1 on all + CPUs). Do not use the console unless there is a debug probe attached + to drain the FDC TX FIFO. + + If unsure, say N. + +config MIPS_EJTAG_FDC_EARLYCON + bool "Early FDC console" + depends on MIPS_EJTAG_FDC_TTY + help + This registers a console on FDC channel 1 very early during boot (from + MIPS arch code). This is useful for bring-up and debugging early boot + issues. + + Do not enable unless there is a debug probe attached to drain the FDC + TX FIFO. + + If unsure, say N. + +config MIPS_EJTAG_FDC_KGDB + bool "Use KGDB over an FDC channel" + depends on MIPS_EJTAG_FDC_TTY && KGDB + default y + help + This enables the use of KGDB over an FDC channel, allowing KGDB to be + used remotely or when a serial port isn't available. + +config MIPS_EJTAG_FDC_KGDB_CHAN + int "KGDB FDC channel" + depends on MIPS_EJTAG_FDC_KGDB + range 2 15 + default 3 + help + FDC channel number to use for KGDB. + +config NULL_TTY + tristate "NULL TTY driver" + help + Say Y here if you want a NULL TTY which simply discards messages. + + This is useful to allow userspace applications which expect a console + device to work without modifications even when no console is + available or desired. + + In order to use this driver, you should redirect the console to this + TTY, or boot the kernel with console=ttynull. + + If unsure, say N. + +config VCC + tristate "Sun Virtual Console Concentrator" + depends on SUN_LDOMS + help + Support for Sun logical domain consoles. + +source "drivers/tty/hvc/Kconfig" + +config RPMSG_TTY + tristate "RPMSG tty driver" + depends on RPMSG + help + Say y here to export rpmsg endpoints as tty devices, usually found + in /dev/ttyRPMSGx. + This makes it possible for user-space programs to send and receive + rpmsg messages as a standard tty protocol. + + To compile this driver as a module, choose M here: the module will be + called rpmsg_tty. + +endif # TTY + +source "drivers/tty/serdev/Kconfig" |