2 # The 8250/16550 serial drivers. You shouldn't be in this list unless
3 # you somehow have an implicit or explicit dependency on SERIAL_8250.
7 tristate "8250/16550 and compatible serial support"
11 This selects whether you want to include the driver for the standard
12 serial ports. The standard answer is Y. People who might say N
13 here are those that are setting up dedicated Ethernet WWW/FTP
14 servers, or users that have one of the various bus mice instead of a
15 serial mouse and don't intend to use their machine's standard serial
16 port for anything. (Note that the Cyclades multi serial port driver
17 does not need this driver built in for it to work.)
19 To compile this driver as a module, choose M here: the
20 module will be called 8250.
21 [WARNING: Do not compile this driver as a module if you are using
22 non-standard serial ports, since the configuration information will
23 be lost when the driver is unloaded. This limitation may be lifted
26 BTW1: If you have a mouseman serial mouse which is not recognized by
27 the X window system, try running gpm first.
29 BTW2: If you intend to use a software modem (also called Winmodem)
30 under Linux, forget it. These modems are crippled and require
31 proprietary drivers which are only available under Windows.
33 Most people will say Y or M here, so that they can use serial mice,
34 modems and similar devices connecting to the standard serial ports.
36 config SERIAL_8250_DEPRECATED_OPTIONS
37 bool "Support 8250_core.* kernel options (DEPRECATED)"
38 depends on SERIAL_8250
41 In 3.7 we renamed 8250 to 8250_core by mistake, so now we have to
42 accept kernel parameters in both forms like 8250_core.nr_uarts=4 and
43 8250.nr_uarts=4. We now renamed the module back to 8250, but if
44 anybody noticed in 3.7 and changed their userspace we still have to
45 keep the 8250_core.* options around until they revert the changes
48 If 8250 is built as a module, this adds 8250_core alias instead.
50 If you did not notice yet and/or you have userspace from pre-3.7, it
51 is safe (and recommended) to say N here.
53 config SERIAL_8250_PNP
54 bool "8250/16550 PNP device support" if EXPERT
55 depends on SERIAL_8250 && PNP
58 This builds standard PNP serial support. You may be able to
59 disable this feature if you only need legacy serial support.
61 config SERIAL_8250_FINTEK
62 bool "Support for Fintek F81216A LPC to 4 UART RS485 API"
63 depends on SERIAL_8250
65 Selecting this option will add support for the RS485 capabilities
66 of the Fintek F81216A LPC to 4 UART.
68 If this option is not selected the device will be configured as a
69 standard 16550A serial port.
73 config SERIAL_8250_CONSOLE
74 bool "Console on 8250/16550 and compatible serial port"
75 depends on SERIAL_8250=y
76 select SERIAL_CORE_CONSOLE
77 select SERIAL_EARLYCON
79 If you say Y here, it will be possible to use a serial port as the
80 system console (the system console is the device which receives all
81 kernel messages and warnings and which allows logins in single user
82 mode). This could be useful if some terminal or printer is connected
85 Even if you say Y here, the currently visible virtual console
86 (/dev/tty0) will still be used as the system console by default, but
87 you can alter that using a kernel command line option such as
88 "console=ttyS1". (Try "man bootparam" or see the documentation of
89 your boot loader (grub or lilo or loadlin) about how to pass options
90 to the kernel at boot time.)
92 If you don't have a VGA card installed and you say Y here, the
93 kernel will automatically use the first serial line, /dev/ttyS0, as
96 You can set that using a kernel command line option such as
97 "console=uart8250,io,0x3f8,9600n8"
98 "console=uart8250,mmio,0xff5e0000,115200n8".
99 and it will switch to normal serial console when the corresponding
101 "earlycon=uart8250,io,0x3f8,9600n8"
102 "earlycon=uart8250,mmio,0xff5e0000,115200n8".
103 it will not only setup early console.
107 config SERIAL_8250_GSC
109 depends on SERIAL_8250 && GSC
112 config SERIAL_8250_DMA
113 bool "DMA support for 16550 compatible UART controllers" if EXPERT
114 depends on SERIAL_8250 && DMADEVICES=y
117 This builds DMA support that can be used with 8250/16650
118 compatible UART controllers that support DMA signaling.
120 config SERIAL_8250_PCI
121 tristate "8250/16550 PCI device support"
122 depends on SERIAL_8250 && PCI
125 This builds standard PCI serial support. You may be able to
126 disable this feature if you only need legacy serial support.
128 Note that serial ports on NetMos 9835 Multi-I/O cards are handled
129 by the parport_serial driver, enabled with CONFIG_PARPORT_SERIAL.
131 config SERIAL_8250_EXAR
132 tristate "8250/16550 Exar/Commtech PCI/PCIe device support"
133 depends on SERIAL_8250_PCI
136 This builds support for XR17C1xx, XR17V3xx and some Commtech
137 422x PCIe serial cards that are not covered by the more generic
138 SERIAL_8250_PCI option.
140 config SERIAL_8250_HP300
142 depends on SERIAL_8250 && HP300
145 config SERIAL_8250_CS
146 tristate "8250/16550 PCMCIA device support"
147 depends on PCMCIA && SERIAL_8250
149 Say Y here to enable support for 16-bit PCMCIA serial devices,
150 including serial port cards, modems, and the modem functions of
151 multi-function Ethernet/modem cards. (PCMCIA- or PC-cards are
152 credit-card size devices often used with laptops.)
154 To compile this driver as a module, choose M here: the
155 module will be called serial_cs.
159 config SERIAL_8250_MEN_MCB
160 tristate "MEN MCB UART device support"
161 depends on MCB && SERIAL_8250
163 This enables support for FPGA based UARTs found on many MEN
164 boards. This driver enables support for the 16z025, 16z057
167 To compile this driver as a module, chose M here: the
168 module will be called 8250_men_mcb.
171 config SERIAL_8250_NR_UARTS
172 int "Maximum number of 8250/16550 serial ports"
173 depends on SERIAL_8250
176 Set this to the number of serial ports you want the driver
177 to support. This includes any ports discovered via ACPI or
178 PCI enumeration and any ports that may be added at run-time
179 via hot-plug, or any ISA multi-port serial cards.
181 config SERIAL_8250_RUNTIME_UARTS
182 int "Number of 8250/16550 serial ports to register at runtime"
183 depends on SERIAL_8250
184 range 0 SERIAL_8250_NR_UARTS
187 Set this to the maximum number of serial ports you want
188 the kernel to register at boot time. This can be overridden
189 with the module parameter "nr_uarts", or boot-time parameter
192 config SERIAL_8250_EXTENDED
193 bool "Extended 8250/16550 serial driver options"
194 depends on SERIAL_8250
196 If you wish to use any non-standard features of the standard "dumb"
197 driver, say Y here. This includes HUB6 support, shared serial
198 interrupts, special multiport support, support for more than the
199 four COM 1/2/3/4 boards, etc.
201 Note that the answer to this question won't directly affect the
202 kernel: saying N will just cause the configurator to skip all
203 the questions about serial driver options. If unsure, say N.
205 config SERIAL_8250_MANY_PORTS
206 bool "Support more than 4 legacy serial ports"
207 depends on SERIAL_8250_EXTENDED && !IA64
209 Say Y here if you have dumb serial boards other than the four
210 standard COM 1/2/3/4 ports. This may happen if you have an AST
211 FourPort, Accent Async, Boca (read the Boca mini-HOWTO, available
212 from <http://www.tldp.org/docs.html#howto>), or other custom
213 serial port hardware which acts similar to standard serial port
214 hardware. If you only use the standard COM 1/2/3/4 ports, you can
215 say N here to save some memory. You can also say Y if you have an
216 "intelligent" multiport card such as Cyclades, Digiboards, etc.
219 # Multi-port serial cards
222 config SERIAL_8250_FOURPORT
223 tristate "Support Fourport cards"
224 depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
226 Say Y here if you have an AST FourPort serial board.
228 To compile this driver as a module, choose M here: the module
229 will be called 8250_fourport.
231 config SERIAL_8250_ACCENT
232 tristate "Support Accent cards"
233 depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
235 Say Y here if you have an Accent Async serial board.
237 To compile this driver as a module, choose M here: the module
238 will be called 8250_accent.
240 config SERIAL_8250_ASPEED_VUART
241 tristate "Aspeed Virtual UART"
242 depends on SERIAL_8250
245 If you want to use the virtual UART (VUART) device on Aspeed
246 BMC platforms, enable this option. This enables the 16550A-
247 compatible device on the local LPC bus, giving a UART device
248 with no physical RS232 connections.
250 config SERIAL_8250_BOCA
251 tristate "Support Boca cards"
252 depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
254 Say Y here if you have a Boca serial board. Please read the Boca
255 mini-HOWTO, available from <http://www.tldp.org/docs.html#howto>
257 To compile this driver as a module, choose M here: the module
258 will be called 8250_boca.
260 config SERIAL_8250_EXAR_ST16C554
261 tristate "Support Exar ST16C554/554D Quad UART"
262 depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
264 The Uplogix Envoy TU301 uses this Exar Quad UART. If you are
265 tinkering with your Envoy TU301, or have a machine with this UART,
268 To compile this driver as a module, choose M here: the module
269 will be called 8250_exar_st16c554.
271 config SERIAL_8250_HUB6
272 tristate "Support Hub6 cards"
273 depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
275 Say Y here if you have a HUB6 serial board.
277 To compile this driver as a module, choose M here: the module
278 will be called 8250_hub6.
281 # Misc. options/drivers.
284 config SERIAL_8250_SHARE_IRQ
285 bool "Support for sharing serial interrupts"
286 depends on SERIAL_8250_EXTENDED
288 Some serial boards have hardware support which allows multiple dumb
289 serial ports on the same board to share a single IRQ. To enable
290 support for this in the serial driver, say Y here.
292 config SERIAL_8250_DETECT_IRQ
293 bool "Autodetect IRQ on standard ports (unsafe)"
294 depends on SERIAL_8250_EXTENDED
296 Say Y here if you want the kernel to try to guess which IRQ
297 to use for your serial port.
299 This is considered unsafe; it is far better to configure the IRQ in
300 a boot script using the setserial command.
304 config SERIAL_8250_RSA
305 bool "Support RSA serial ports"
306 depends on SERIAL_8250_EXTENDED
308 Say Y here if you have a IODATA RSA-DV II/S ISA card and
309 would like to use its >115kbps speeds.
310 You will need to provide module parameter "probe_rsa", or boot-time
311 parameter 8250.probe_rsa with I/O addresses of this card then.
313 If you don't have such card, or if unsure, say N.
315 config SERIAL_8250_ACORN
316 tristate "Acorn expansion card serial port support"
317 depends on ARCH_ACORN && SERIAL_8250
319 If you have an Atomwide Serial card or Serial Port card for an Acorn
320 system, say Y to this option. The driver can handle 1, 2, or 3 port
321 cards. If unsure, say N.
323 config SERIAL_8250_BCM2835AUX
324 tristate "BCM2835 auxiliar mini UART support"
325 depends on ARCH_BCM2835 || COMPILE_TEST
326 depends on SERIAL_8250 && SERIAL_8250_SHARE_IRQ
328 Support for the BCM2835 auxiliar mini UART.
330 Features and limitations of the UART are
331 Registers are similar to 16650 registers,
332 set bits in the control registers that are unsupported
333 are ignored and read back as 0
334 7/8 bit operation with 1 start and 1 stop bit
335 8 symbols deep fifo for rx and tx
336 SW controlled RTS and SW readable CTS
337 Clock rate derived from system clock
338 Uses 8 times oversampling (compared to 16 times for 16650)
339 Missing break detection (but break generation)
340 Missing framing error detection
342 Missing receive time-out interrupt
343 Missing DCD, DSR, DTR and RI signals
347 config SERIAL_8250_FSL
349 depends on SERIAL_8250_CONSOLE
350 default PPC || ARM || ARM64
352 config SERIAL_8250_DW
353 tristate "Support for Synopsys DesignWare 8250 quirks"
354 depends on SERIAL_8250
356 Selecting this option will enable handling of the extra features
357 present in the Synopsys DesignWare APB UART.
359 config SERIAL_8250_EM
360 tristate "Support for Emma Mobile integrated serial port"
361 depends on SERIAL_8250 && ARM && HAVE_CLK
363 Selecting this option will add support for the integrated serial
364 port hardware found on the Emma Mobile line of processors.
367 config SERIAL_8250_RT288X
368 bool "Ralink RT288x/RT305x/RT3662/RT3883 serial port support"
369 depends on SERIAL_8250
370 default y if MIPS_ALCHEMY || SOC_RT288X || SOC_RT305X || SOC_RT3883 || SOC_MT7620
372 Selecting this option will add support for the alternate register
373 layout used by Ralink RT288x/RT305x, Alchemy Au1xxx, and some others.
376 config SERIAL_8250_OMAP
377 tristate "Support for OMAP internal UART (8250 based driver)"
378 depends on SERIAL_8250 && ARCH_OMAP2PLUS
380 If you have a machine based on an Texas Instruments OMAP CPU you
381 can enable its onboard serial ports by enabling this option.
383 This driver uses ttyS instead of ttyO.
385 config SERIAL_8250_OMAP_TTYO_FIXUP
386 bool "Replace ttyO with ttyS"
387 depends on SERIAL_8250_OMAP=y && SERIAL_8250_CONSOLE
390 This option replaces the "console=ttyO" argument with the matching
391 ttyS argument if the user did not specified it on the command line.
392 This ensures that the user can see the kernel output during boot
393 which he wouldn't see otherwise. The getty has still to be configured
394 for ttyS instead of ttyO regardless of this option.
395 This option is intended for people who "automatically" enable this
396 driver without knowing that this driver requires a different console=
397 argument. If you read this, please keep this option disabled and
398 instead update your kernel command line. If you prepare a kernel for a
399 distribution or other kind of larger user base then you probably want
400 to keep this option enabled. Otherwise people might complain about a
401 not booting kernel because the serial console remains silent in case
402 they forgot to update the command line.
404 config SERIAL_8250_LPC18XX
405 tristate "NXP LPC18xx/43xx serial port support"
406 depends on SERIAL_8250 && OF && (ARCH_LPC18XX || COMPILE_TEST)
409 If you have a LPC18xx/43xx based board and want to use the
410 serial port, say Y to this option. If unsure, say Y.
412 config SERIAL_8250_MT6577
413 tristate "Mediatek serial port support"
414 depends on SERIAL_8250 && ARCH_MEDIATEK
416 If you have a Mediatek based board and want to use the
417 serial port, say Y to this option. If unsure, say N.
419 config SERIAL_8250_UNIPHIER
420 tristate "Support for UniPhier on-chip UART"
421 depends on SERIAL_8250
422 depends on ARCH_UNIPHIER || COMPILE_TEST
424 If you have a UniPhier based board and want to use the on-chip
425 serial ports, say Y to this option. If unsure, say N.
427 config SERIAL_8250_INGENIC
428 tristate "Support for Ingenic SoC serial ports"
429 depends on SERIAL_8250
430 depends on OF_FLATTREE
431 depends on MIPS || COMPILE_TEST
433 If you have a system using an Ingenic SoC and wish to make use of
434 its UARTs, say Y to this option. If unsure, say N.
436 config SERIAL_8250_LPSS
437 tristate "Support for serial ports on Intel LPSS platforms"
439 depends on SERIAL_8250 && PCI
440 depends on X86 || COMPILE_TEST
441 select DW_DMAC_CORE if SERIAL_8250_DMA
442 select DW_DMAC_PCI if (SERIAL_8250_DMA && X86_INTEL_LPSS)
445 Selecting this option will enable handling of the extra features
446 present on the UART found on various Intel platforms such as:
449 - Intel Quark X1000 SoC
451 config SERIAL_8250_MID
452 tristate "Support for serial ports on Intel MID platforms"
454 depends on SERIAL_8250 && PCI
455 depends on X86 || COMPILE_TEST
456 select HSU_DMA if SERIAL_8250_DMA
457 select HSU_DMA_PCI if (HSU_DMA && X86_INTEL_MID)
460 Selecting this option will enable handling of the extra features
461 present on the UART found on Intel Medfield SOC and various other
464 config SERIAL_8250_MOXA
465 tristate "MOXA SmartIO MUE support"
466 depends on SERIAL_8250 && PCI
468 Say Y here if you have a Moxa SmartIO MUE multiport serial card.
471 This driver can also be built as a module. The module will be called
472 8250_moxa. If you want to do that, say M here.
474 config SERIAL_8250_PXA
475 tristate "PXA serial port support"
476 depends on SERIAL_8250
477 depends on ARCH_PXA || ARCH_MMP
479 If you have a machine based on an Intel XScale PXA2xx CPU you can
480 enable its onboard serial ports by enabling this option. The option is
481 applicable to both devicetree and legacy boards, and early console is
484 config SERIAL_OF_PLATFORM
485 tristate "Devicetree based probing for 8250 ports"
486 depends on SERIAL_8250 && OF
488 This option is used for all 8250 compatible serial ports that
489 are probed through devicetree, including Open Firmware based
490 PowerPC systems and embedded systems on architectures using the
491 flattened device tree format.