# SPDX-License-Identifier: GPL-2.0
#
# The 8250/16550 serial drivers. You shouldn't be in this list unless
# you somehow have an implicit or explicit dependency on [31mCONFIG_SERIAL_8250[0m.
#
config [31mCONFIG_SERIAL_8250[0m
tristate "8250/16550 and compatible serial support"
depends on ![31mCONFIG_S390[0m
select [31mCONFIG_SERIAL_CORE[0m
select [31mCONFIG_SERIAL_MCTRL_GPIO[0m if [31mCONFIG_GPIOLIB[0m
---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 multi serial port driver
does not need this driver built in for it to work.)
To compile this driver as a module, choose [31mCONFIG_M[0m 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 [31mCONFIG_M[0m here, so that they can use serial mice,
modems and similar devices connecting to the standard serial ports.
config [31mCONFIG_SERIAL_8250_DEPRECATED_OPTIONS[0m
bool "Support 8250_core.* kernel options (DEPRECATED)"
depends on [31mCONFIG_SERIAL_8250[0m
default y
---help---
In 3.7 we renamed 8250 to 8250_core by mistake, so now we have to
accept kernel parameters in both forms like 8250_core.nr_uarts=4 and
8250.nr_uarts=4. We now renamed the module back to 8250, but if
anybody noticed in 3.7 and changed their userspace we still have to
keep the 8250_core.* options around until they revert the changes
they already did.
If 8250 is built as a module, this adds 8250_core alias instead.
If you did not notice yet and/or you have userspace from pre-3.7, it
is safe (and recommended) to say N here.
config [31mCONFIG_SERIAL_8250_PNP[0m
bool "8250/16550 PNP device support" if [31mCONFIG_EXPERT[0m
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_PNP[0m
default y
---help---
This builds standard [31mCONFIG_PNP[0m serial support. You may be able to
disable this feature if you only need legacy serial support.
config [31mCONFIG_SERIAL_8250_FINTEK[0m
bool "Support for Fintek F81216A LPC to 4 UART RS485 API"
depends on [31mCONFIG_SERIAL_8250[0m
---help---
Selecting this option will add support for the RS485 capabilities
of the Fintek F81216A LPC to 4 UART.
If this option is not selected the device will be configured as a
standard 16550A serial port.
If unsure, say N.
config [31mCONFIG_SERIAL_8250_CONSOLE[0m
bool "Console on 8250/16550 and compatible serial port"
depends on [31mCONFIG_SERIAL_8250[0m=y
select [31mCONFIG_SERIAL_CORE_CONSOLE[0m
select [31mCONFIG_SERIAL_EARLYCON[0m
---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 [31mCONFIG_SERIAL_8250_GSC[0m
tristate
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_GSC[0m
default [31mCONFIG_SERIAL_8250[0m
config [31mCONFIG_SERIAL_8250_DMA[0m
bool "DMA support for 16550 compatible UART controllers" if [31mCONFIG_EXPERT[0m
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_DMADEVICES[0m=y
default [31mCONFIG_SERIAL_8250[0m
help
This builds DMA support that can be used with 8250/16650
compatible UART controllers that support DMA signaling.
config [31mCONFIG_SERIAL_8250_PCI[0m
tristate "8250/16550 PCI device support"
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_PCI[0m
default [31mCONFIG_SERIAL_8250[0m
help
This builds standard [31mCONFIG_PCI[0m serial support. You may be able to
disable this feature if you only need legacy serial support.
Saves about 9K.
Note that serial ports on NetMos 9835 Multi-I/O cards are handled
by the parport_serial driver, enabled with CONFIG_PARPORT_SERIAL.
config [31mCONFIG_SERIAL_8250_EXAR[0m
tristate "8250/16550 Exar/Commtech PCI/PCIe device support"
depends on [31mCONFIG_SERIAL_8250_PCI[0m
default [31mCONFIG_SERIAL_8250[0m
help
This builds support for XR17C1xx, XR17V3xx and some Commtech
422x PCIe serial cards that are not covered by the more generic
[31mCONFIG_SERIAL_8250_PCI[0m option.
config [31mCONFIG_SERIAL_8250_HP300[0m
tristate
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_HP300[0m
default [31mCONFIG_SERIAL_8250[0m
config [31mCONFIG_SERIAL_8250_CS[0m
tristate "8250/16550 PCMCIA device support"
depends on [31mCONFIG_PCMCIA[0m && [31mCONFIG_SERIAL_8250[0m
---help---
Say Y here to enable support for 16-bit [31mCONFIG_PCMCIA[0m serial devices,
including serial port cards, modems, and the modem functions of
multi-function Ethernet/modem cards. ([31mCONFIG_PCMCIA[0m- or PC-cards are
credit-card size devices often used with laptops.)
To compile this driver as a module, choose [31mCONFIG_M[0m here: the
module will be called serial_cs.
If unsure, say N.
config [31mCONFIG_SERIAL_8250_MEN_MCB[0m
tristate "MEN MCB UART device support"
depends on [31mCONFIG_MCB[0m && [31mCONFIG_SERIAL_8250[0m
help
This enables support for [31mCONFIG_FPGA[0m based UARTs found on many MEN
boards. This driver enables support for the 16z025, 16z057
and 16z125 UARTs.
To compile this driver as a module, chose [31mCONFIG_M[0m here: the
module will be called 8250_men_mcb.
config [31mCONFIG_SERIAL_8250_NR_UARTS[0m
int "Maximum number of 8250/16550 serial ports"
depends on [31mCONFIG_SERIAL_8250[0m
default "4"
help
Set this to the number of serial ports you want the driver
to support. This includes any ports discovered via [31mCONFIG_ACPI[0m or
[31mCONFIG_PCI[0m enumeration and any ports that may be added at run-time
via hot-plug, or any [31mCONFIG_ISA[0m multi-port serial cards.
config [31mCONFIG_SERIAL_8250_RUNTIME_UARTS[0m
int "Number of 8250/16550 serial ports to register at runtime"
depends on [31mCONFIG_SERIAL_8250[0m
range 0 [31mCONFIG_SERIAL_8250_NR_UARTS[0m
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 [31mCONFIG_SERIAL_8250_EXTENDED[0m
bool "Extended 8250/16550 serial driver options"
depends on [31mCONFIG_SERIAL_8250[0m
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 [31mCONFIG_SERIAL_8250_MANY_PORTS[0m
bool "Support more than 4 legacy serial ports"
depends on [31mCONFIG_SERIAL_8250_EXTENDED[0m && ![31mCONFIG_IA64[0m
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 [31mCONFIG_SERIAL_8250_FOURPORT[0m
tristate "Support Fourport cards"
depends on [31mCONFIG_SERIAL_8250[0m != n && [31mCONFIG_ISA[0m && [31mCONFIG_SERIAL_8250_MANY_PORTS[0m
help
Say Y here if you have an AST FourPort serial board.
To compile this driver as a module, choose [31mCONFIG_M[0m here: the module
will be called 8250_fourport.
config [31mCONFIG_SERIAL_8250_ACCENT[0m
tristate "Support Accent cards"
depends on [31mCONFIG_SERIAL_8250[0m != n && [31mCONFIG_ISA[0m && [31mCONFIG_SERIAL_8250_MANY_PORTS[0m
help
Say Y here if you have an Accent Async serial board.
To compile this driver as a module, choose [31mCONFIG_M[0m here: the module
will be called 8250_accent.
config [31mCONFIG_SERIAL_8250_ASPEED_VUART[0m
tristate "Aspeed Virtual UART"
depends on [31mCONFIG_SERIAL_8250[0m
depends on [31mCONFIG_OF[0m
help
If you want to use the virtual UART (VUART) device on Aspeed
BMC platforms, enable this option. This enables the 16550A-
compatible device on the local LPC bus, giving a UART device
with no physical RS232 connections.
config [31mCONFIG_SERIAL_8250_BOCA[0m
tristate "Support Boca cards"
depends on [31mCONFIG_SERIAL_8250[0m != n && [31mCONFIG_ISA[0m && [31mCONFIG_SERIAL_8250_MANY_PORTS[0m
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 [31mCONFIG_M[0m here: the module
will be called 8250_boca.
config [31mCONFIG_SERIAL_8250_EXAR_ST16C554[0m
tristate "Support Exar ST16C554/554D Quad UART"
depends on [31mCONFIG_SERIAL_8250[0m != n && [31mCONFIG_ISA[0m && [31mCONFIG_SERIAL_8250_MANY_PORTS[0m
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 [31mCONFIG_M[0m here: the module
will be called 8250_exar_st16c554.
config [31mCONFIG_SERIAL_8250_HUB6[0m
tristate "Support Hub6 cards"
depends on [31mCONFIG_SERIAL_8250[0m != n && [31mCONFIG_ISA[0m && [31mCONFIG_SERIAL_8250_MANY_PORTS[0m
help
Say Y here if you have a HUB6 serial board.
To compile this driver as a module, choose [31mCONFIG_M[0m here: the module
will be called 8250_hub6.
#
# Misc. options/drivers.
#
config [31mCONFIG_SERIAL_8250_SHARE_IRQ[0m
bool "Support for sharing serial interrupts"
depends on [31mCONFIG_SERIAL_8250_EXTENDED[0m
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 [31mCONFIG_SERIAL_8250_DETECT_IRQ[0m
bool "Autodetect IRQ on standard ports (unsafe)"
depends on [31mCONFIG_SERIAL_8250_EXTENDED[0m
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 [31mCONFIG_SERIAL_8250_RSA[0m
bool "Support RSA serial ports"
depends on [31mCONFIG_SERIAL_8250_EXTENDED[0m
help
Say Y here if you have a IODATA RSA-DV II/S [31mCONFIG_ISA[0m card and
would like to use its >115kbps speeds.
You will need to provide module parameter "probe_rsa", or boot-time
parameter 8250.probe_rsa with I/O addresses of this card then.
If you don't have such card, or if unsure, say N.
config [31mCONFIG_SERIAL_8250_DWLIB[0m
bool
config [31mCONFIG_SERIAL_8250_ACORN[0m
tristate "Acorn expansion card serial port support"
depends on [31mCONFIG_ARCH_ACORN[0m && [31mCONFIG_SERIAL_8250[0m
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 [31mCONFIG_SERIAL_8250_BCM2835AUX[0m
tristate "BCM2835 auxiliar mini UART support"
depends on [31mCONFIG_ARCH_BCM2835[0m || [31mCONFIG_COMPILE_TEST[0m
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_SERIAL_8250_SHARE_IRQ[0m
help
Support for the BCM2835 auxiliar mini UART.
Features and limitations of the UART are
Registers are similar to 16650 registers,
set bits in the control registers that are unsupported
are ignored and read back as 0
7/8 bit operation with 1 start and 1 stop bit
8 symbols deep fifo for rx and tx
SW controlled RTS and SW readable CTS
Clock rate derived from system clock
Uses 8 times oversampling (compared to 16 times for 16650)
Missing break detection (but break generation)
Missing framing error detection
Missing parity bit
Missing receive time-out interrupt
Missing DCD, DSR, DTR and RI signals
If unsure, say N.
config [31mCONFIG_SERIAL_8250_FSL[0m
bool
depends on [31mCONFIG_SERIAL_8250_CONSOLE[0m
default [31mCONFIG_PPC[0m || [31mCONFIG_ARM[0m || [31mCONFIG_ARM64[0m
config [31mCONFIG_SERIAL_8250_DW[0m
tristate "Support for Synopsys DesignWare 8250 quirks"
depends on [31mCONFIG_SERIAL_8250[0m
select [31mCONFIG_SERIAL_8250_DWLIB[0m
help
Selecting this option will enable handling of the extra features
present in the Synopsys DesignWare APB UART.
config [31mCONFIG_SERIAL_8250_EM[0m
tristate "Support for Emma Mobile integrated serial port"
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_ARM[0m && [31mCONFIG_HAVE_CLK[0m
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.
config [31mCONFIG_SERIAL_8250_RT288X[0m
bool "Ralink RT288x/RT305x/RT3662/RT3883 serial port support"
depends on [31mCONFIG_SERIAL_8250[0m
default y if [31mCONFIG_MIPS_ALCHEMY[0m || [31mCONFIG_SOC_RT288X[0m || [31mCONFIG_SOC_RT305X[0m || [31mCONFIG_SOC_RT3883[0m || [31mCONFIG_SOC_MT7620[0m
help
Selecting this option will add support for the alternate register
layout used by Ralink RT288x/RT305x, Alchemy Au1xxx, and some others.
If unsure, say N.
config [31mCONFIG_SERIAL_8250_OMAP[0m
tristate "Support for OMAP internal UART (8250 based driver)"
depends on [31mCONFIG_SERIAL_8250[0m && ([31mCONFIG_ARCH_OMAP2PLUS[0m || [31mCONFIG_ARCH_K3[0m)
help
If you have a machine based on an Texas Instruments OMAP CPU you
can enable its onboard serial ports by enabling this option.
This driver uses ttyS instead of ttyO.
config [31mCONFIG_SERIAL_8250_OMAP_TTYO_FIXUP[0m
bool "Replace ttyO with ttyS"
depends on [31mCONFIG_SERIAL_8250_OMAP[0m=y && [31mCONFIG_SERIAL_8250_CONSOLE[0m
default y
help
This option replaces the "console=ttyO" argument with the matching
ttyS argument if the user did not specified it on the command line.
This ensures that the user can see the kernel output during boot
which he wouldn't see otherwise. The getty has still to be configured
for ttyS instead of ttyO regardless of this option.
This option is intended for people who "automatically" enable this
driver without knowing that this driver requires a different console=
argument. If you read this, please keep this option disabled and
instead update your kernel command line. If you prepare a kernel for a
distribution or other kind of larger user base then you probably want
to keep this option enabled. Otherwise people might complain about a
not booting kernel because the serial console remains silent in case
they forgot to update the command line.
config [31mCONFIG_SERIAL_8250_LPC18XX[0m
tristate "NXP LPC18xx/43xx serial port support"
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_OF[0m && ([31mCONFIG_ARCH_LPC18XX[0m || [31mCONFIG_COMPILE_TEST[0m)
default [31mCONFIG_ARCH_LPC18XX[0m
help
If you have a LPC18xx/43xx based board and want to use the
serial port, say Y to this option. If unsure, say Y.
config [31mCONFIG_SERIAL_8250_MT6577[0m
tristate "Mediatek serial port support"
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_ARCH_MEDIATEK[0m
help
If you have a Mediatek based board and want to use the
serial port, say Y to this option. If unsure, say N.
config [31mCONFIG_SERIAL_8250_UNIPHIER[0m
tristate "Support for UniPhier on-chip UART"
depends on [31mCONFIG_SERIAL_8250[0m
depends on [31mCONFIG_ARCH_UNIPHIER[0m || [31mCONFIG_COMPILE_TEST[0m
help
If you have a UniPhier based board and want to use the on-chip
serial ports, say Y to this option. If unsure, say N.
config [31mCONFIG_SERIAL_8250_INGENIC[0m
tristate "Support for Ingenic SoC serial ports"
depends on [31mCONFIG_SERIAL_8250[0m
depends on [31mCONFIG_OF_FLATTREE[0m
depends on [31mCONFIG_MIPS[0m || [31mCONFIG_COMPILE_TEST[0m
help
If you have a system using an Ingenic SoC and wish to make use of
its UARTs, say Y to this option. If unsure, say N.
config [31mCONFIG_SERIAL_8250_LPSS[0m
tristate "Support for serial ports on Intel LPSS platforms"
default [31mCONFIG_SERIAL_8250[0m
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_PCI[0m
depends on [31mCONFIG_X86[0m || [31mCONFIG_COMPILE_TEST[0m
select [31mCONFIG_SERIAL_8250_DWLIB[0m
select [31mCONFIG_DW_DMAC_CORE[0m if [31mCONFIG_SERIAL_8250_DMA[0m
select [31mCONFIG_DW_DMAC_PCI[0m if ([31mCONFIG_SERIAL_8250_DMA[0m && [31mCONFIG_X86_INTEL_LPSS[0m)
select [31mCONFIG_RATIONAL[0m
help
Selecting this option will enable handling of the extra features
present on the UART found on various Intel platforms such as:
- Intel Baytrail SoC
- Intel Braswell SoC
- Intel Quark X1000 SoC
config [31mCONFIG_SERIAL_8250_MID[0m
tristate "Support for serial ports on Intel MID platforms"
default [31mCONFIG_SERIAL_8250[0m
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_PCI[0m
depends on [31mCONFIG_X86[0m || [31mCONFIG_COMPILE_TEST[0m
select [31mCONFIG_HSU_DMA[0m if [31mCONFIG_SERIAL_8250_DMA[0m
select [31mCONFIG_HSU_DMA_PCI[0m if ([31mCONFIG_HSU_DMA[0m && [31mCONFIG_X86_INTEL_MID[0m)
select [31mCONFIG_RATIONAL[0m
help
Selecting this option will enable handling of the extra features
present on the UART found on Intel Medfield SOC and various other
Intel platforms.
config [31mCONFIG_SERIAL_8250_PXA[0m
tristate "PXA serial port support"
depends on [31mCONFIG_SERIAL_8250[0m
depends on [31mCONFIG_ARCH_PXA[0m || [31mCONFIG_ARCH_MMP[0m
help
If you have a machine based on an Intel XScale PXA2xx CPU you can
enable its onboard serial ports by enabling this option. The option is
applicable to both devicetree and legacy boards, and early console is
part of its support.
config [31mCONFIG_SERIAL_OF_PLATFORM[0m
tristate "Devicetree based probing for 8250 ports"
depends on [31mCONFIG_SERIAL_8250[0m && [31mCONFIG_OF[0m
help
This option is used for all 8250 compatible serial ports that
are probed through devicetree, including Open Firmware based
PowerPC systems and embedded systems on architectures using the
flattened device tree format.