xref: /openbmc/linux/drivers/tty/serial/8250/Kconfig (revision 023e4163)
1#
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.
4#
5
6config SERIAL_8250
7	tristate "8250/16550 and compatible serial support"
8	depends on !S390
9	select SERIAL_CORE
10	---help---
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.)
18
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
24	  in the future.]
25
26	  BTW1: If you have a mouseman serial mouse which is not recognized by
27	  the X window system, try running gpm first.
28
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.
32
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.
35
36config SERIAL_8250_DEPRECATED_OPTIONS
37	bool "Support 8250_core.* kernel options (DEPRECATED)"
38	depends on SERIAL_8250
39	default y
40	---help---
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
46	  they already did.
47
48	  If 8250 is built as a module, this adds 8250_core alias instead.
49
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.
52
53config SERIAL_8250_PNP
54	bool "8250/16550 PNP device support" if EXPERT
55	depends on SERIAL_8250 && PNP
56	default y
57	---help---
58	  This builds standard PNP serial support. You may be able to
59	  disable this feature if you only need legacy serial support.
60
61config SERIAL_8250_FINTEK
62	bool "Support for Fintek F81216A LPC to 4 UART RS485 API"
63	depends on SERIAL_8250
64	---help---
65	  Selecting this option will add support for the RS485 capabilities
66	  of the Fintek F81216A LPC to 4 UART.
67
68	  If this option is not selected the device will be configured as a
69	  standard 16550A serial port.
70
71	  If unsure, say N.
72
73config 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
78	---help---
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
83	  to that serial port.
84
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.)
91
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
94	  system console.
95
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
100	  port is ready.
101	  "earlycon=uart8250,io,0x3f8,9600n8"
102	  "earlycon=uart8250,mmio,0xff5e0000,115200n8".
103	  it will not only setup early console.
104
105	  If unsure, say N.
106
107config SERIAL_8250_GSC
108	tristate
109	depends on SERIAL_8250 && GSC
110	default SERIAL_8250
111
112config SERIAL_8250_DMA
113	bool "DMA support for 16550 compatible UART controllers" if EXPERT
114	depends on SERIAL_8250 && DMADEVICES=y
115	default SERIAL_8250
116	help
117	  This builds DMA support that can be used with 8250/16650
118	  compatible UART controllers that support DMA signaling.
119
120config SERIAL_8250_PCI
121	tristate "8250/16550 PCI device support"
122	depends on SERIAL_8250 && PCI
123	default SERIAL_8250
124	help
125	  This builds standard PCI serial support. You may be able to
126	  disable this feature if you only need legacy serial support.
127	  Saves about 9K.
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.
130
131config SERIAL_8250_EXAR
132	tristate "8250/16550 Exar/Commtech PCI/PCIe device support"
133	depends on SERIAL_8250_PCI
134	default SERIAL_8250
135	help
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.
139
140config SERIAL_8250_HP300
141	tristate
142	depends on SERIAL_8250 && HP300
143	default SERIAL_8250
144
145config SERIAL_8250_CS
146	tristate "8250/16550 PCMCIA device support"
147	depends on PCMCIA && SERIAL_8250
148	---help---
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.)
153
154	  To compile this driver as a module, choose M here: the
155	  module will be called serial_cs.
156
157	  If unsure, say N.
158
159config SERIAL_8250_MEN_MCB
160	tristate "MEN MCB UART device support"
161	depends on MCB && SERIAL_8250
162	help
163	  This enables support for FPGA based UARTs found on many MEN
164	  boards. This driver enables support for the 16z025, 16z057
165	  and 16z125 UARTs.
166
167	  To compile this driver as a module, chose M here: the
168	  module will be called 8250_men_mcb.
169
170
171config SERIAL_8250_NR_UARTS
172	int "Maximum number of 8250/16550 serial ports"
173	depends on SERIAL_8250
174	default "4"
175	help
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.
180
181config 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
185	default "4"
186	help
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
190	  8250.nr_uarts
191
192config SERIAL_8250_EXTENDED
193	bool "Extended 8250/16550 serial driver options"
194	depends on SERIAL_8250
195	help
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.
200
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.
204
205config SERIAL_8250_MANY_PORTS
206	bool "Support more than 4 legacy serial ports"
207	depends on SERIAL_8250_EXTENDED && !IA64
208	help
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.
217
218#
219# Multi-port serial cards
220#
221
222config SERIAL_8250_FOURPORT
223	tristate "Support Fourport cards"
224	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
225	help
226	  Say Y here if you have an AST FourPort serial board.
227
228	  To compile this driver as a module, choose M here: the module
229	  will be called 8250_fourport.
230
231config SERIAL_8250_ACCENT
232	tristate "Support Accent cards"
233	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
234	help
235	  Say Y here if you have an Accent Async serial board.
236
237	  To compile this driver as a module, choose M here: the module
238	  will be called 8250_accent.
239
240config SERIAL_8250_ASPEED_VUART
241	tristate "Aspeed Virtual UART"
242	depends on SERIAL_8250
243	depends on OF
244	help
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.
249
250config SERIAL_8250_BOCA
251	tristate "Support Boca cards"
252	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
253	help
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>
256
257	  To compile this driver as a module, choose M here: the module
258	  will be called 8250_boca.
259
260config SERIAL_8250_EXAR_ST16C554
261	tristate "Support Exar ST16C554/554D Quad UART"
262	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
263	help
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,
266	  say Y here.
267
268	  To compile this driver as a module, choose M here: the module
269	  will be called 8250_exar_st16c554.
270
271config SERIAL_8250_HUB6
272	tristate "Support Hub6 cards"
273	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
274	help
275	  Say Y here if you have a HUB6 serial board.
276
277	  To compile this driver as a module, choose M here: the module
278	  will be called 8250_hub6.
279
280#
281# Misc. options/drivers.
282#
283
284config SERIAL_8250_SHARE_IRQ
285	bool "Support for sharing serial interrupts"
286	depends on SERIAL_8250_EXTENDED
287	help
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.
291
292config SERIAL_8250_DETECT_IRQ
293	bool "Autodetect IRQ on standard ports (unsafe)"
294	depends on SERIAL_8250_EXTENDED
295	help
296	  Say Y here if you want the kernel to try to guess which IRQ
297	  to use for your serial port.
298
299	  This is considered unsafe; it is far better to configure the IRQ in
300	  a boot script using the setserial command.
301
302	  If unsure, say N.
303
304config SERIAL_8250_RSA
305	bool "Support RSA serial ports"
306	depends on SERIAL_8250_EXTENDED
307	help
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.
312
313	  If you don't have such card, or if unsure, say N.
314
315config SERIAL_8250_ACORN
316	tristate "Acorn expansion card serial port support"
317	depends on ARCH_ACORN && SERIAL_8250
318	help
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.
322
323config 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
327	help
328	  Support for the BCM2835 auxiliar mini UART.
329
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
341	    Missing parity bit
342	    Missing receive time-out interrupt
343	    Missing DCD, DSR, DTR and RI signals
344
345	  If unsure, say N.
346
347config SERIAL_8250_FSL
348	bool
349	depends on SERIAL_8250_CONSOLE
350	default PPC || ARM || ARM64
351
352config SERIAL_8250_DW
353	tristate "Support for Synopsys DesignWare 8250 quirks"
354	depends on SERIAL_8250
355	help
356	  Selecting this option will enable handling of the extra features
357	  present in the Synopsys DesignWare APB UART.
358
359config SERIAL_8250_EM
360	tristate "Support for Emma Mobile integrated serial port"
361	depends on SERIAL_8250 && ARM && HAVE_CLK
362	help
363	  Selecting this option will add support for the integrated serial
364	  port hardware found on the Emma Mobile line of processors.
365	  If unsure, say N.
366
367config 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
371	help
372	  Selecting this option will add support for the alternate register
373	  layout used by Ralink RT288x/RT305x, Alchemy Au1xxx, and some others.
374	  If unsure, say N.
375
376config SERIAL_8250_OMAP
377	tristate "Support for OMAP internal UART (8250 based driver)"
378	depends on SERIAL_8250 && (ARCH_OMAP2PLUS || ARCH_K3)
379	help
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.
382
383	  This driver uses ttyS instead of ttyO.
384
385config SERIAL_8250_OMAP_TTYO_FIXUP
386	bool "Replace ttyO with ttyS"
387	depends on SERIAL_8250_OMAP=y && SERIAL_8250_CONSOLE
388	default y
389	help
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.
403
404config SERIAL_8250_LPC18XX
405	tristate "NXP LPC18xx/43xx serial port support"
406	depends on SERIAL_8250 && OF && (ARCH_LPC18XX || COMPILE_TEST)
407	default ARCH_LPC18XX
408	help
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.
411
412config SERIAL_8250_MT6577
413	tristate "Mediatek serial port support"
414	depends on SERIAL_8250 && ARCH_MEDIATEK
415	help
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.
418
419config SERIAL_8250_UNIPHIER
420	tristate "Support for UniPhier on-chip UART"
421	depends on SERIAL_8250
422	depends on ARCH_UNIPHIER || COMPILE_TEST
423	help
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.
426
427config 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
432	help
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.
435
436config SERIAL_8250_LPSS
437	tristate "Support for serial ports on Intel LPSS platforms"
438	default SERIAL_8250
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)
443	select RATIONAL
444	help
445	  Selecting this option will enable handling of the extra features
446	  present on the UART found on various Intel platforms such as:
447	    - Intel Baytrail SoC
448	    - Intel Braswell SoC
449	    - Intel Quark X1000 SoC
450
451config SERIAL_8250_MID
452	tristate "Support for serial ports on Intel MID platforms"
453	default SERIAL_8250
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)
458	select RATIONAL
459	help
460	  Selecting this option will enable handling of the extra features
461	  present on the UART found on Intel Medfield SOC and various other
462	  Intel platforms.
463
464config SERIAL_8250_MOXA
465	tristate "MOXA SmartIO MUE support"
466	depends on SERIAL_8250 && PCI
467	help
468	  Say Y here if you have a Moxa SmartIO MUE multiport serial card.
469	  If unsure, say N.
470
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.
473
474config SERIAL_8250_PXA
475	tristate "PXA serial port support"
476	depends on SERIAL_8250
477	depends on ARCH_PXA || ARCH_MMP
478	help
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
482	  part of its support.
483
484config SERIAL_OF_PLATFORM
485	tristate "Devicetree based probing for 8250 ports"
486	depends on SERIAL_8250 && OF
487	help
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.
492