xref: /openbmc/linux/drivers/tty/serial/8250/Kconfig (revision d3964221)
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	select SERIAL_CORE
9	---help---
10	  This selects whether you want to include the driver for the standard
11	  serial ports.  The standard answer is Y.  People who might say N
12	  here are those that are setting up dedicated Ethernet WWW/FTP
13	  servers, or users that have one of the various bus mice instead of a
14	  serial mouse and don't intend to use their machine's standard serial
15	  port for anything.  (Note that the Cyclades multi serial port driver
16	  does not need this driver built in for it to work.)
17
18	  To compile this driver as a module, choose M here: the
19	  module will be called 8250.
20	  [WARNING: Do not compile this driver as a module if you are using
21	  non-standard serial ports, since the configuration information will
22	  be lost when the driver is unloaded.  This limitation may be lifted
23	  in the future.]
24
25	  BTW1: If you have a mouseman serial mouse which is not recognized by
26	  the X window system, try running gpm first.
27
28	  BTW2: If you intend to use a software modem (also called Winmodem)
29	  under Linux, forget it.  These modems are crippled and require
30	  proprietary drivers which are only available under Windows.
31
32	  Most people will say Y or M here, so that they can use serial mice,
33	  modems and similar devices connecting to the standard serial ports.
34
35config SERIAL_8250_DEPRECATED_OPTIONS
36	bool "Support 8250_core.* kernel options (DEPRECATED)"
37	depends on SERIAL_8250
38	default y
39	---help---
40	  In 3.7 we renamed 8250 to 8250_core by mistake, so now we have to
41	  accept kernel parameters in both forms like 8250_core.nr_uarts=4 and
42	  8250.nr_uarts=4. We now renamed the module back to 8250, but if
43	  anybody noticed in 3.7 and changed their userspace we still have to
44	  keep the 8250_core.* options around until they revert the changes
45	  they already did.
46
47	  If 8250 is built as a module, this adds 8250_core alias instead.
48
49	  If you did not notice yet and/or you have userspace from pre-3.7, it
50	  is safe (and recommended) to say N here.
51
52config SERIAL_8250_PNP
53	bool "8250/16550 PNP device support" if EXPERT
54	depends on SERIAL_8250 && PNP
55	default y
56	---help---
57	  This builds standard PNP serial support. You may be able to
58	  disable this feature if you only need legacy serial support.
59
60config SERIAL_8250_FINTEK
61	bool "Support for Fintek F81216A LPC to 4 UART RS485 API"
62	depends on SERIAL_8250
63	---help---
64	  Selecting this option will add support for the RS485 capabilities
65	  of the Fintek F81216A LPC to 4 UART.
66
67	  If this option is not selected the device will be configured as a
68	  standard 16550A serial port.
69
70	  If unsure, say N.
71
72config SERIAL_8250_CONSOLE
73	bool "Console on 8250/16550 and compatible serial port"
74	depends on SERIAL_8250=y
75	select SERIAL_CORE_CONSOLE
76	select SERIAL_EARLYCON
77	---help---
78	  If you say Y here, it will be possible to use a serial port as the
79	  system console (the system console is the device which receives all
80	  kernel messages and warnings and which allows logins in single user
81	  mode). This could be useful if some terminal or printer is connected
82	  to that serial port.
83
84	  Even if you say Y here, the currently visible virtual console
85	  (/dev/tty0) will still be used as the system console by default, but
86	  you can alter that using a kernel command line option such as
87	  "console=ttyS1". (Try "man bootparam" or see the documentation of
88	  your boot loader (grub or lilo or loadlin) about how to pass options
89	  to the kernel at boot time.)
90
91	  If you don't have a VGA card installed and you say Y here, the
92	  kernel will automatically use the first serial line, /dev/ttyS0, as
93	  system console.
94
95	  You can set that using a kernel command line option such as
96	  "console=uart8250,io,0x3f8,9600n8"
97	  "console=uart8250,mmio,0xff5e0000,115200n8".
98	  and it will switch to normal serial console when the corresponding
99	  port is ready.
100	  "earlycon=uart8250,io,0x3f8,9600n8"
101	  "earlycon=uart8250,mmio,0xff5e0000,115200n8".
102	  it will not only setup early console.
103
104	  If unsure, say N.
105
106config SERIAL_8250_GSC
107	tristate
108	depends on SERIAL_8250 && GSC
109	default SERIAL_8250
110
111config SERIAL_8250_DMA
112	bool "DMA support for 16550 compatible UART controllers" if EXPERT
113	depends on SERIAL_8250 && DMADEVICES=y
114	default SERIAL_8250
115	help
116	  This builds DMA support that can be used with 8250/16650
117	  compatible UART controllers that support DMA signaling.
118
119config SERIAL_8250_PCI
120	tristate "8250/16550 PCI device support"
121	depends on SERIAL_8250 && PCI
122	default SERIAL_8250
123	help
124	  This builds standard PCI serial support. You may be able to
125	  disable this feature if you only need legacy serial support.
126	  Saves about 9K.
127	  Note that serial ports on NetMos 9835 Multi-I/O cards are handled
128	  by the parport_serial driver, enabled with CONFIG_PARPORT_SERIAL.
129
130config SERIAL_8250_EXAR
131	tristate "8250/16550 Exar/Commtech PCI/PCIe device support"
132	depends on SERIAL_8250_PCI
133	default SERIAL_8250
134	help
135	  This builds support for XR17C1xx, XR17V3xx and some Commtech
136	  422x PCIe serial cards that are not covered by the more generic
137	  SERIAL_8250_PCI option.
138
139config SERIAL_8250_HP300
140	tristate
141	depends on SERIAL_8250 && HP300
142	default SERIAL_8250
143
144config SERIAL_8250_CS
145	tristate "8250/16550 PCMCIA device support"
146	depends on PCMCIA && SERIAL_8250
147	---help---
148	  Say Y here to enable support for 16-bit PCMCIA serial devices,
149	  including serial port cards, modems, and the modem functions of
150	  multi-function Ethernet/modem cards. (PCMCIA- or PC-cards are
151	  credit-card size devices often used with laptops.)
152
153	  To compile this driver as a module, choose M here: the
154	  module will be called serial_cs.
155
156	  If unsure, say N.
157
158config SERIAL_8250_MEN_MCB
159	tristate "MEN Z125 UART device support"
160	depends on MCB && SERIAL_8250
161	help
162	  This enables support for FPGA based UARTs found on many MEN
163	  boards. This driver enables support for the Z125 UARTs.
164
165	  To compile this driver as a module, chose M here: the
166	  module will be called 8250_men_mcb.
167
168
169config SERIAL_8250_NR_UARTS
170	int "Maximum number of 8250/16550 serial ports"
171	depends on SERIAL_8250
172	default "4"
173	help
174	  Set this to the number of serial ports you want the driver
175	  to support.  This includes any ports discovered via ACPI or
176	  PCI enumeration and any ports that may be added at run-time
177	  via hot-plug, or any ISA multi-port serial cards.
178
179config SERIAL_8250_RUNTIME_UARTS
180	int "Number of 8250/16550 serial ports to register at runtime"
181	depends on SERIAL_8250
182	range 0 SERIAL_8250_NR_UARTS
183	default "4"
184	help
185	  Set this to the maximum number of serial ports you want
186	  the kernel to register at boot time.  This can be overridden
187	  with the module parameter "nr_uarts", or boot-time parameter
188	  8250.nr_uarts
189
190config SERIAL_8250_EXTENDED
191	bool "Extended 8250/16550 serial driver options"
192	depends on SERIAL_8250
193	help
194	  If you wish to use any non-standard features of the standard "dumb"
195	  driver, say Y here. This includes HUB6 support, shared serial
196	  interrupts, special multiport support, support for more than the
197	  four COM 1/2/3/4 boards, etc.
198
199	  Note that the answer to this question won't directly affect the
200	  kernel: saying N will just cause the configurator to skip all
201	  the questions about serial driver options. If unsure, say N.
202
203config SERIAL_8250_MANY_PORTS
204	bool "Support more than 4 legacy serial ports"
205	depends on SERIAL_8250_EXTENDED && !IA64
206	help
207	  Say Y here if you have dumb serial boards other than the four
208	  standard COM 1/2/3/4 ports. This may happen if you have an AST
209	  FourPort, Accent Async, Boca (read the Boca mini-HOWTO, available
210	  from <http://www.tldp.org/docs.html#howto>), or other custom
211	  serial port hardware which acts similar to standard serial port
212	  hardware. If you only use the standard COM 1/2/3/4 ports, you can
213	  say N here to save some memory. You can also say Y if you have an
214	  "intelligent" multiport card such as Cyclades, Digiboards, etc.
215
216#
217# Multi-port serial cards
218#
219
220config SERIAL_8250_FOURPORT
221	tristate "Support Fourport cards"
222	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
223	help
224	  Say Y here if you have an AST FourPort serial board.
225
226	  To compile this driver as a module, choose M here: the module
227	  will be called 8250_fourport.
228
229config SERIAL_8250_ACCENT
230	tristate "Support Accent cards"
231	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
232	help
233	  Say Y here if you have an Accent Async serial board.
234
235	  To compile this driver as a module, choose M here: the module
236	  will be called 8250_accent.
237
238config SERIAL_8250_ASPEED_VUART
239	tristate "Aspeed Virtual UART"
240	depends on SERIAL_8250
241	depends on OF
242	help
243	  If you want to use the virtual UART (VUART) device on Aspeed
244	  BMC platforms, enable this option. This enables the 16550A-
245	  compatible device on the local LPC bus, giving a UART device
246	  with no physical RS232 connections.
247
248config SERIAL_8250_BOCA
249	tristate "Support Boca cards"
250	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
251	help
252	  Say Y here if you have a Boca serial board.  Please read the Boca
253	  mini-HOWTO, available from <http://www.tldp.org/docs.html#howto>
254
255	  To compile this driver as a module, choose M here: the module
256	  will be called 8250_boca.
257
258config SERIAL_8250_EXAR_ST16C554
259	tristate "Support Exar ST16C554/554D Quad UART"
260	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
261	help
262	  The Uplogix Envoy TU301 uses this Exar Quad UART.  If you are
263	  tinkering with your Envoy TU301, or have a machine with this UART,
264	  say Y here.
265
266	  To compile this driver as a module, choose M here: the module
267	  will be called 8250_exar_st16c554.
268
269config SERIAL_8250_HUB6
270	tristate "Support Hub6 cards"
271	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
272	help
273	  Say Y here if you have a HUB6 serial board.
274
275	  To compile this driver as a module, choose M here: the module
276	  will be called 8250_hub6.
277
278#
279# Misc. options/drivers.
280#
281
282config SERIAL_8250_SHARE_IRQ
283	bool "Support for sharing serial interrupts"
284	depends on SERIAL_8250_EXTENDED
285	help
286	  Some serial boards have hardware support which allows multiple dumb
287	  serial ports on the same board to share a single IRQ. To enable
288	  support for this in the serial driver, say Y here.
289
290config SERIAL_8250_DETECT_IRQ
291	bool "Autodetect IRQ on standard ports (unsafe)"
292	depends on SERIAL_8250_EXTENDED
293	help
294	  Say Y here if you want the kernel to try to guess which IRQ
295	  to use for your serial port.
296
297	  This is considered unsafe; it is far better to configure the IRQ in
298	  a boot script using the setserial command.
299
300	  If unsure, say N.
301
302config SERIAL_8250_RSA
303	bool "Support RSA serial ports"
304	depends on SERIAL_8250_EXTENDED
305	help
306	  Say Y here if you have a IODATA RSA-DV II/S ISA card and
307	  would like to use its >115kbps speeds.
308	  You will need to provide module parameter "probe_rsa", or boot-time
309	  parameter 8250.probe_rsa with I/O addresses of this card then.
310
311	  If you don't have such card, or if unsure, say N.
312
313config SERIAL_8250_ACORN
314	tristate "Acorn expansion card serial port support"
315	depends on ARCH_ACORN && SERIAL_8250
316	help
317	  If you have an Atomwide Serial card or Serial Port card for an Acorn
318	  system, say Y to this option.  The driver can handle 1, 2, or 3 port
319	  cards.  If unsure, say N.
320
321config SERIAL_8250_BCM2835AUX
322	tristate "BCM2835 auxiliar mini UART support"
323	depends on ARCH_BCM2835 || COMPILE_TEST
324	depends on SERIAL_8250 && SERIAL_8250_SHARE_IRQ
325	help
326	  Support for the BCM2835 auxiliar mini UART.
327
328	  Features and limitations of the UART are
329	    Registers are similar to 16650 registers,
330              set bits in the control registers that are unsupported
331	      are ignored and read back as 0
332	    7/8 bit operation with 1 start and 1 stop bit
333	    8 symbols deep fifo for rx and tx
334	    SW controlled RTS and SW readable CTS
335	    Clock rate derived from system clock
336	    Uses 8 times oversampling (compared to 16 times for 16650)
337	    Missing break detection (but break generation)
338	    Missing framing error detection
339	    Missing parity bit
340	    Missing receive time-out interrupt
341	    Missing DCD, DSR, DTR and RI signals
342
343	  If unsure, say N.
344
345config SERIAL_8250_FSL
346	bool
347	depends on SERIAL_8250_CONSOLE
348	default PPC || ARM || ARM64
349
350config SERIAL_8250_DW
351	tristate "Support for Synopsys DesignWare 8250 quirks"
352	depends on SERIAL_8250
353	help
354	  Selecting this option will enable handling of the extra features
355	  present in the Synopsys DesignWare APB UART.
356
357config SERIAL_8250_EM
358	tristate "Support for Emma Mobile integrated serial port"
359	depends on SERIAL_8250 && ARM && HAVE_CLK
360	help
361	  Selecting this option will add support for the integrated serial
362	  port hardware found on the Emma Mobile line of processors.
363	  If unsure, say N.
364
365config SERIAL_8250_RT288X
366	bool "Ralink RT288x/RT305x/RT3662/RT3883 serial port support"
367	depends on SERIAL_8250
368	default y if MIPS_ALCHEMY || SOC_RT288X || SOC_RT305X || SOC_RT3883 || SOC_MT7620
369	help
370	  Selecting this option will add support for the alternate register
371	  layout used by Ralink RT288x/RT305x, Alchemy Au1xxx, and some others.
372	  If unsure, say N.
373
374config SERIAL_8250_OMAP
375	tristate "Support for OMAP internal UART (8250 based driver)"
376	depends on SERIAL_8250 && ARCH_OMAP2PLUS
377	help
378	  If you have a machine based on an Texas Instruments OMAP CPU you
379	  can enable its onboard serial ports by enabling this option.
380
381	  This driver uses ttyS instead of ttyO.
382
383config SERIAL_8250_OMAP_TTYO_FIXUP
384	bool "Replace ttyO with ttyS"
385	depends on SERIAL_8250_OMAP=y && SERIAL_8250_CONSOLE
386	default y
387	help
388	  This option replaces the "console=ttyO" argument with the matching
389	  ttyS argument if the user did not specified it on the command line.
390	  This ensures that the user can see the kernel output during boot
391	  which he wouldn't see otherwise. The getty has still to be configured
392	  for ttyS instead of ttyO regardless of this option.
393	  This option is intended for people who "automatically" enable this
394	  driver without knowing that this driver requires a different console=
395	  argument. If you read this, please keep this option disabled and
396	  instead update your kernel command line. If you prepare a kernel for a
397	  distribution or other kind of larger user base then you probably want
398	  to keep this option enabled. Otherwise people might complain about a
399	  not booting kernel because the serial console remains silent in case
400	  they forgot to update the command line.
401
402config SERIAL_8250_LPC18XX
403	tristate "NXP LPC18xx/43xx serial port support"
404	depends on SERIAL_8250 && OF && (ARCH_LPC18XX || COMPILE_TEST)
405	default ARCH_LPC18XX
406	help
407	  If you have a LPC18xx/43xx based board and want to use the
408	  serial port, say Y to this option. If unsure, say Y.
409
410config SERIAL_8250_MT6577
411	tristate "Mediatek serial port support"
412	depends on SERIAL_8250 && ARCH_MEDIATEK
413	help
414	  If you have a Mediatek based board and want to use the
415	  serial port, say Y to this option. If unsure, say N.
416
417config SERIAL_8250_UNIPHIER
418	tristate "Support for UniPhier on-chip UART"
419	depends on SERIAL_8250
420	depends on ARCH_UNIPHIER || COMPILE_TEST
421	help
422	  If you have a UniPhier based board and want to use the on-chip
423	  serial ports, say Y to this option. If unsure, say N.
424
425config SERIAL_8250_INGENIC
426	tristate "Support for Ingenic SoC serial ports"
427	depends on SERIAL_8250
428	depends on OF_FLATTREE
429	depends on MIPS || COMPILE_TEST
430	help
431	  If you have a system using an Ingenic SoC and wish to make use of
432	  its UARTs, say Y to this option. If unsure, say N.
433
434config SERIAL_8250_LPSS
435	tristate "Support for serial ports on Intel LPSS platforms"
436	default SERIAL_8250
437	depends on SERIAL_8250 && PCI
438	depends on X86 || COMPILE_TEST
439	select DW_DMAC_CORE if SERIAL_8250_DMA
440	select DW_DMAC_PCI if (SERIAL_8250_DMA && X86_INTEL_LPSS)
441	select RATIONAL
442	help
443	  Selecting this option will enable handling of the extra features
444	  present on the UART found on various Intel platforms such as:
445	    - Intel Baytrail SoC
446	    - Intel Braswell SoC
447	    - Intel Quark X1000 SoC
448
449config SERIAL_8250_MID
450	tristate "Support for serial ports on Intel MID platforms"
451	default SERIAL_8250
452	depends on SERIAL_8250 && PCI
453	depends on X86 || COMPILE_TEST
454	select HSU_DMA if SERIAL_8250_DMA
455	select HSU_DMA_PCI if (HSU_DMA && X86_INTEL_MID)
456	select RATIONAL
457	help
458	  Selecting this option will enable handling of the extra features
459	  present on the UART found on Intel Medfield SOC and various other
460	  Intel platforms.
461
462config SERIAL_8250_MOXA
463	tristate "MOXA SmartIO MUE support"
464	depends on SERIAL_8250 && PCI
465	help
466	  Say Y here if you have a Moxa SmartIO MUE multiport serial card.
467	  If unsure, say N.
468
469	  This driver can also be built as a module. The module will be called
470	  8250_moxa. If you want to do that, say M here.
471
472config SERIAL_8250_PXA
473	tristate "PXA serial port support"
474	depends on SERIAL_8250
475	depends on ARCH_PXA || ARCH_MMP
476	help
477	  If you have a machine based on an Intel XScale PXA2xx CPU you can
478	  enable its onboard serial ports by enabling this option. The option is
479	  applicable to both devicetree and legacy boards, and early console is
480	  part of its support.
481
482config SERIAL_OF_PLATFORM
483	tristate "Devicetree based probing for 8250 ports"
484	depends on SERIAL_8250 && OF
485	help
486	  This option is used for all 8250 compatible serial ports that
487	  are probed through devicetree, including Open Firmware based
488	  PowerPC systems and embedded systems on architectures using the
489	  flattened device tree format.
490