drivers/tty/serial/8250/Kconfig - linux - Git at Google

 #
 # The 8250/16550 serial drivers.  You shouldn't be in this list unless
 # you somehow have an implicit or explicit dependency on SERIAL_8250.
 #

 config SERIAL_8250
 	tristate "8250/16550 and compatible serial support"
 	select SERIAL_CORE
 	---help---
 	  This selects whether you want to include the driver for the standard
 	  serial ports.  The standard answer is Y.  People who might say N
 	  here are those that are setting up dedicated Ethernet WWW/FTP
 	  servers, or users that have one of the various bus mice instead of a
 	  serial mouse and don't intend to use their machine's standard serial
 	  port for anything.  (Note that the Cyclades and Stallion multi
 	  serial port drivers do not need this driver built in for them to
 	  work.)

 	  To compile this driver as a module, choose M here: the
 	  module will be called 8250.
 	  [WARNING: Do not compile this driver as a module if you are using
 	  non-standard serial ports, since the configuration information will
 	  be lost when the driver is unloaded.  This limitation may be lifted
 	  in the future.]

 	  BTW1: If you have a mouseman serial mouse which is not recognized by
 	  the X window system, try running gpm first.

 	  BTW2: If you intend to use a software modem (also called Winmodem)
 	  under Linux, forget it.  These modems are crippled and require
 	  proprietary drivers which are only available under Windows.

 	  Most people will say Y or M here, so that they can use serial mice,
 	  modems and similar devices connecting to the standard serial ports.

 config SERIAL_8250_CONSOLE
 	bool "Console on 8250/16550 and compatible serial port"
 	depends on SERIAL_8250=y
 	select SERIAL_CORE_CONSOLE
 	---help---
 	  If you say Y here, it will be possible to use a serial port as the
 	  system console (the system console is the device which receives all
 	  kernel messages and warnings and which allows logins in single user
 	  mode). This could be useful if some terminal or printer is connected
 	  to that serial port.

 	  Even if you say Y here, the currently visible virtual console
 	  (/dev/tty0) will still be used as the system console by default, but
 	  you can alter that using a kernel command line option such as
 	  "console=ttyS1". (Try "man bootparam" or see the documentation of
 	  your boot loader (grub or lilo or loadlin) about how to pass options
 	  to the kernel at boot time.)

 	  If you don't have a VGA card installed and you say Y here, the
 	  kernel will automatically use the first serial line, /dev/ttyS0, as
 	  system console.

 	  You can set that using a kernel command line option such as
 	  "console=uart8250,io,0x3f8,9600n8"
 	  "console=uart8250,mmio,0xff5e0000,115200n8".
 	  and it will switch to normal serial console when the corresponding
 	  port is ready.
 	  "earlycon=uart8250,io,0x3f8,9600n8"
 	  "earlycon=uart8250,mmio,0xff5e0000,115200n8".
 	  it will not only setup early console.

 	  If unsure, say N.

 config FIX_EARLYCON_MEM
 	bool
 	depends on X86
 	default y

 config SERIAL_8250_GSC
 	tristate
 	depends on SERIAL_8250 && GSC
 	default SERIAL_8250

 config SERIAL_8250_PCI
 	tristate "8250/16550 PCI device support" if EXPERT
 	depends on SERIAL_8250 && PCI
 	default SERIAL_8250
 	help
 	  This builds standard PCI serial support. You may be able to
 	  disable this feature if you only need legacy serial support.
 	  Saves about 9K.

 config SERIAL_8250_PNP
 	tristate "8250/16550 PNP device support" if EXPERT
 	depends on SERIAL_8250 && PNP
 	default SERIAL_8250
 	help
 	  This builds standard PNP serial support. You may be able to
 	  disable this feature if you only need legacy serial support.

 config SERIAL_8250_HP300
 	tristate
 	depends on SERIAL_8250 && HP300
 	default SERIAL_8250

 config SERIAL_8250_CS
 	tristate "8250/16550 PCMCIA device support"
 	depends on PCMCIA && SERIAL_8250
 	---help---
 	  Say Y here to enable support for 16-bit PCMCIA serial devices,
 	  including serial port cards, modems, and the modem functions of
 	  multi-function Ethernet/modem cards. (PCMCIA- or PC-cards are
 	  credit-card size devices often used with laptops.)

 	  To compile this driver as a module, choose M here: the
 	  module will be called serial_cs.

 	  If unsure, say N.

 config SERIAL_8250_NR_UARTS
 	int "Maximum number of 8250/16550 serial ports"
 	depends on SERIAL_8250
 	default "4"
 	help
 	  Set this to the number of serial ports you want the driver
 	  to support.  This includes any ports discovered via ACPI or
 	  PCI enumeration and any ports that may be added at run-time
 	  via hot-plug, or any ISA multi-port serial cards.

 config SERIAL_8250_RUNTIME_UARTS
 	int "Number of 8250/16550 serial ports to register at runtime"
 	depends on SERIAL_8250
 	range 0 SERIAL_8250_NR_UARTS
 	default "4"
 	help
 	  Set this to the maximum number of serial ports you want
 	  the kernel to register at boot time.  This can be overridden
 	  with the module parameter "nr_uarts", or boot-time parameter
 	  8250.nr_uarts

 config SERIAL_8250_EXTENDED
 	bool "Extended 8250/16550 serial driver options"
 	depends on SERIAL_8250
 	help
 	  If you wish to use any non-standard features of the standard "dumb"
 	  driver, say Y here. This includes HUB6 support, shared serial
 	  interrupts, special multiport support, support for more than the
 	  four COM 1/2/3/4 boards, etc.

 	  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 serial driver options. If unsure, say N.

 config SERIAL_8250_MANY_PORTS
 	bool "Support more than 4 legacy serial ports"
 	depends on SERIAL_8250_EXTENDED && !IA64
 	help
 	  Say Y here if you have dumb serial boards other than the four
 	  standard COM 1/2/3/4 ports. This may happen if you have an AST
 	  FourPort, Accent Async, Boca (read the Boca mini-HOWTO, available
 	  from <http://www.tldp.org/docs.html#howto>), or other custom
 	  serial port hardware which acts similar to standard serial port
 	  hardware. If you only use the standard COM 1/2/3/4 ports, you can
 	  say N here to save some memory. You can also say Y if you have an
 	  "intelligent" multiport card such as Cyclades, Digiboards, etc.

 #
 # Multi-port serial cards
 #

 config SERIAL_8250_FOURPORT
 	tristate "Support Fourport cards"
 	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
 	help
 	  Say Y here if you have an AST FourPort serial board.

 	  To compile this driver as a module, choose M here: the module
 	  will be called 8250_fourport.

 config SERIAL_8250_ACCENT
 	tristate "Support Accent cards"
 	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
 	help
 	  Say Y here if you have an Accent Async serial board.

 	  To compile this driver as a module, choose M here: the module
 	  will be called 8250_accent.

 config SERIAL_8250_BOCA
 	tristate "Support Boca cards"
 	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
 	help
 	  Say Y here if you have a Boca serial board.  Please read the Boca
 	  mini-HOWTO, available from <http://www.tldp.org/docs.html#howto>

 	  To compile this driver as a module, choose M here: the module
 	  will be called 8250_boca.

 config SERIAL_8250_EXAR_ST16C554
 	tristate "Support Exar ST16C554/554D Quad UART"
 	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
 	help
 	  The Uplogix Envoy TU301 uses this Exar Quad UART.  If you are
 	  tinkering with your Envoy TU301, or have a machine with this UART,
 	  say Y here.

 	  To compile this driver as a module, choose M here: the module
 	  will be called 8250_exar_st16c554.

 config SERIAL_8250_HUB6
 	tristate "Support Hub6 cards"
 	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
 	help
 	  Say Y here if you have a HUB6 serial board.

 	  To compile this driver as a module, choose M here: the module
 	  will be called 8250_hub6.

 #
 # Misc. options/drivers.
 #

 config SERIAL_8250_SHARE_IRQ
 	bool "Support for sharing serial interrupts"
 	depends on SERIAL_8250_EXTENDED
 	help
 	  Some serial boards have hardware support which allows multiple dumb
 	  serial ports on the same board to share a single IRQ. To enable
 	  support for this in the serial driver, say Y here.

 config SERIAL_8250_DETECT_IRQ
 	bool "Autodetect IRQ on standard ports (unsafe)"
 	depends on SERIAL_8250_EXTENDED
 	help
 	  Say Y here if you want the kernel to try to guess which IRQ
 	  to use for your serial port.

 	  This is considered unsafe; it is far better to configure the IRQ in
 	  a boot script using the setserial command.

 	  If unsure, say N.

 config SERIAL_8250_RSA
 	bool "Support RSA serial ports"
 	depends on SERIAL_8250_EXTENDED
 	help
 	  ::: To be written :::

 config SERIAL_8250_ACORN
 	tristate "Acorn expansion card serial port support"
 	depends on ARCH_ACORN && SERIAL_8250
 	help
 	  If you have an Atomwide Serial card or Serial Port card for an Acorn
 	  system, say Y to this option.  The driver can handle 1, 2, or 3 port
 	  cards.  If unsure, say N.

 config SERIAL_8250_RM9K
 	bool "Support for MIPS RM9xxx integrated serial port"
 	depends on SERIAL_8250 != n && SERIAL_RM9000
 	select SERIAL_8250_SHARE_IRQ
 	help
 	  Selecting this option will add support for the integrated serial
 	  port hardware found on MIPS RM9122 and similar processors.
 	  If unsure, say N.

 config SERIAL_8250_FSL
 	bool
 	depends on SERIAL_8250_CONSOLE && PPC_UDBG_16550
 	default PPC

 config SERIAL_8250_DW
 	tristate "Support for Synopsys DesignWare 8250 quirks"
 	depends on SERIAL_8250 && OF
 	help
 	  Selecting this option will enable handling of the extra features
 	  present in the Synopsys DesignWare APB UART.

 config SERIAL_8250_EM
 	tristate "Support for Emma Mobile intergrated serial port"
 	depends on SERIAL_8250 && ARM && HAVE_CLK
 	help
 	  Selecting this option will add support for the integrated serial
 	  port hardware found on the Emma Mobile line of processors.
 	  If unsure, say N.
	#
	# The 8250/16550 serial drivers. You shouldn't be in this list unless
	# you somehow have an implicit or explicit dependency on SERIAL_8250.
	#

	config SERIAL_8250
	tristate "8250/16550 and compatible serial support"
	select SERIAL_CORE
	---help---
	This selects whether you want to include the driver for the standard
	serial ports. The standard answer is Y. People who might say N
	here are those that are setting up dedicated Ethernet WWW/FTP
	servers, or users that have one of the various bus mice instead of a
	serial mouse and don't intend to use their machine's standard serial
	port for anything. (Note that the Cyclades and Stallion multi
	serial port drivers do not need this driver built in for them to
	work.)

	To compile this driver as a module, choose M here: the
	module will be called 8250.
	[WARNING: Do not compile this driver as a module if you are using
	non-standard serial ports, since the configuration information will
	be lost when the driver is unloaded. This limitation may be lifted
	in the future.]

	BTW1: If you have a mouseman serial mouse which is not recognized by
	the X window system, try running gpm first.

	BTW2: If you intend to use a software modem (also called Winmodem)
	under Linux, forget it. These modems are crippled and require
	proprietary drivers which are only available under Windows.

	Most people will say Y or M here, so that they can use serial mice,
	modems and similar devices connecting to the standard serial ports.

	config SERIAL_8250_CONSOLE
	bool "Console on 8250/16550 and compatible serial port"
	depends on SERIAL_8250=y
	select SERIAL_CORE_CONSOLE
	---help---
	If you say Y here, it will be possible to use a serial port as the
	system console (the system console is the device which receives all
	kernel messages and warnings and which allows logins in single user
	mode). This could be useful if some terminal or printer is connected
	to that serial port.

	Even if you say Y here, the currently visible virtual console
	(/dev/tty0) will still be used as the system console by default, but
	you can alter that using a kernel command line option such as
	"console=ttyS1". (Try "man bootparam" or see the documentation of
	your boot loader (grub or lilo or loadlin) about how to pass options
	to the kernel at boot time.)

	If you don't have a VGA card installed and you say Y here, the
	kernel will automatically use the first serial line, /dev/ttyS0, as
	system console.

	You can set that using a kernel command line option such as
	"console=uart8250,io,0x3f8,9600n8"
	"console=uart8250,mmio,0xff5e0000,115200n8".
	and it will switch to normal serial console when the corresponding
	port is ready.
	"earlycon=uart8250,io,0x3f8,9600n8"
	"earlycon=uart8250,mmio,0xff5e0000,115200n8".
	it will not only setup early console.

	If unsure, say N.

	config FIX_EARLYCON_MEM
	bool
	depends on X86
	default y

	config SERIAL_8250_GSC
	tristate
	depends on SERIAL_8250 && GSC
	default SERIAL_8250

	config SERIAL_8250_PCI
	tristate "8250/16550 PCI device support" if EXPERT
	depends on SERIAL_8250 && PCI
	default SERIAL_8250
	help
	This builds standard PCI serial support. You may be able to
	disable this feature if you only need legacy serial support.
	Saves about 9K.

	config SERIAL_8250_PNP
	tristate "8250/16550 PNP device support" if EXPERT
	depends on SERIAL_8250 && PNP
	default SERIAL_8250
	help
	This builds standard PNP serial support. You may be able to
	disable this feature if you only need legacy serial support.

	config SERIAL_8250_HP300
	tristate
	depends on SERIAL_8250 && HP300
	default SERIAL_8250

	config SERIAL_8250_CS
	tristate "8250/16550 PCMCIA device support"
	depends on PCMCIA && SERIAL_8250
	---help---
	Say Y here to enable support for 16-bit PCMCIA serial devices,
	including serial port cards, modems, and the modem functions of
	multi-function Ethernet/modem cards. (PCMCIA- or PC-cards are
	credit-card size devices often used with laptops.)

	To compile this driver as a module, choose M here: the
	module will be called serial_cs.

	If unsure, say N.

	config SERIAL_8250_NR_UARTS
	int "Maximum number of 8250/16550 serial ports"
	depends on SERIAL_8250
	default "4"
	help
	Set this to the number of serial ports you want the driver
	to support. This includes any ports discovered via ACPI or
	PCI enumeration and any ports that may be added at run-time
	via hot-plug, or any ISA multi-port serial cards.

	config SERIAL_8250_RUNTIME_UARTS
	int "Number of 8250/16550 serial ports to register at runtime"
	depends on SERIAL_8250
	range 0 SERIAL_8250_NR_UARTS
	default "4"
	help
	Set this to the maximum number of serial ports you want
	the kernel to register at boot time. This can be overridden
	with the module parameter "nr_uarts", or boot-time parameter
	8250.nr_uarts

	config SERIAL_8250_EXTENDED
	bool "Extended 8250/16550 serial driver options"
	depends on SERIAL_8250
	help
	If you wish to use any non-standard features of the standard "dumb"
	driver, say Y here. This includes HUB6 support, shared serial
	interrupts, special multiport support, support for more than the
	four COM 1/2/3/4 boards, etc.

	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 serial driver options. If unsure, say N.

	config SERIAL_8250_MANY_PORTS
	bool "Support more than 4 legacy serial ports"
	depends on SERIAL_8250_EXTENDED && !IA64
	help
	Say Y here if you have dumb serial boards other than the four
	standard COM 1/2/3/4 ports. This may happen if you have an AST
	FourPort, Accent Async, Boca (read the Boca mini-HOWTO, available
	from <http://www.tldp.org/docs.html#howto>), or other custom
	serial port hardware which acts similar to standard serial port
	hardware. If you only use the standard COM 1/2/3/4 ports, you can
	say N here to save some memory. You can also say Y if you have an
	"intelligent" multiport card such as Cyclades, Digiboards, etc.

	#
	# Multi-port serial cards
	#

	config SERIAL_8250_FOURPORT
	tristate "Support Fourport cards"
	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
	help
	Say Y here if you have an AST FourPort serial board.

	To compile this driver as a module, choose M here: the module
	will be called 8250_fourport.

	config SERIAL_8250_ACCENT
	tristate "Support Accent cards"
	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
	help
	Say Y here if you have an Accent Async serial board.

	To compile this driver as a module, choose M here: the module
	will be called 8250_accent.

	config SERIAL_8250_BOCA
	tristate "Support Boca cards"
	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
	help
	Say Y here if you have a Boca serial board. Please read the Boca
	mini-HOWTO, available from <http://www.tldp.org/docs.html#howto>

	To compile this driver as a module, choose M here: the module
	will be called 8250_boca.

	config SERIAL_8250_EXAR_ST16C554
	tristate "Support Exar ST16C554/554D Quad UART"
	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
	help
	The Uplogix Envoy TU301 uses this Exar Quad UART. If you are
	tinkering with your Envoy TU301, or have a machine with this UART,
	say Y here.

	To compile this driver as a module, choose M here: the module
	will be called 8250_exar_st16c554.

	config SERIAL_8250_HUB6
	tristate "Support Hub6 cards"
	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
	help
	Say Y here if you have a HUB6 serial board.

	To compile this driver as a module, choose M here: the module
	will be called 8250_hub6.

	#
	# Misc. options/drivers.
	#

	config SERIAL_8250_SHARE_IRQ
	bool "Support for sharing serial interrupts"
	depends on SERIAL_8250_EXTENDED
	help
	Some serial boards have hardware support which allows multiple dumb
	serial ports on the same board to share a single IRQ. To enable
	support for this in the serial driver, say Y here.

	config SERIAL_8250_DETECT_IRQ
	bool "Autodetect IRQ on standard ports (unsafe)"
	depends on SERIAL_8250_EXTENDED
	help
	Say Y here if you want the kernel to try to guess which IRQ
	to use for your serial port.

	This is considered unsafe; it is far better to configure the IRQ in
	a boot script using the setserial command.

	If unsure, say N.

	config SERIAL_8250_RSA
	bool "Support RSA serial ports"
	depends on SERIAL_8250_EXTENDED
	help
	::: To be written :::

	config SERIAL_8250_ACORN
	tristate "Acorn expansion card serial port support"
	depends on ARCH_ACORN && SERIAL_8250
	help
	If you have an Atomwide Serial card or Serial Port card for an Acorn
	system, say Y to this option. The driver can handle 1, 2, or 3 port
	cards. If unsure, say N.

	config SERIAL_8250_RM9K
	bool "Support for MIPS RM9xxx integrated serial port"
	depends on SERIAL_8250 != n && SERIAL_RM9000
	select SERIAL_8250_SHARE_IRQ
	help
	Selecting this option will add support for the integrated serial
	port hardware found on MIPS RM9122 and similar processors.
	If unsure, say N.

	config SERIAL_8250_FSL
	bool
	depends on SERIAL_8250_CONSOLE && PPC_UDBG_16550
	default PPC

	config SERIAL_8250_DW
	tristate "Support for Synopsys DesignWare 8250 quirks"
	depends on SERIAL_8250 && OF
	help
	Selecting this option will enable handling of the extra features
	present in the Synopsys DesignWare APB UART.

	config SERIAL_8250_EM
	tristate "Support for Emma Mobile intergrated serial port"
	depends on SERIAL_8250 && ARM && HAVE_CLK
	help
	Selecting this option will add support for the integrated serial
	port hardware found on the Emma Mobile line of processors.
	If unsure, say N.