xref: /openbmc/linux/drivers/tty/serial/8250/Kconfig (revision 0c380187)
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 PCI device support"
132        depends on SERIAL_8250_PCI
133	default SERIAL_8250
134
135config SERIAL_8250_HP300
136	tristate
137	depends on SERIAL_8250 && HP300
138	default SERIAL_8250
139
140config SERIAL_8250_CS
141	tristate "8250/16550 PCMCIA device support"
142	depends on PCMCIA && SERIAL_8250
143	---help---
144	  Say Y here to enable support for 16-bit PCMCIA serial devices,
145	  including serial port cards, modems, and the modem functions of
146	  multi-function Ethernet/modem cards. (PCMCIA- or PC-cards are
147	  credit-card size devices often used with laptops.)
148
149	  To compile this driver as a module, choose M here: the
150	  module will be called serial_cs.
151
152	  If unsure, say N.
153
154config SERIAL_8250_NR_UARTS
155	int "Maximum number of 8250/16550 serial ports"
156	depends on SERIAL_8250
157	default "4"
158	help
159	  Set this to the number of serial ports you want the driver
160	  to support.  This includes any ports discovered via ACPI or
161	  PCI enumeration and any ports that may be added at run-time
162	  via hot-plug, or any ISA multi-port serial cards.
163
164config SERIAL_8250_RUNTIME_UARTS
165	int "Number of 8250/16550 serial ports to register at runtime"
166	depends on SERIAL_8250
167	range 0 SERIAL_8250_NR_UARTS
168	default "4"
169	help
170	  Set this to the maximum number of serial ports you want
171	  the kernel to register at boot time.  This can be overridden
172	  with the module parameter "nr_uarts", or boot-time parameter
173	  8250.nr_uarts
174
175config SERIAL_8250_EXTENDED
176	bool "Extended 8250/16550 serial driver options"
177	depends on SERIAL_8250
178	help
179	  If you wish to use any non-standard features of the standard "dumb"
180	  driver, say Y here. This includes HUB6 support, shared serial
181	  interrupts, special multiport support, support for more than the
182	  four COM 1/2/3/4 boards, etc.
183
184	  Note that the answer to this question won't directly affect the
185	  kernel: saying N will just cause the configurator to skip all
186	  the questions about serial driver options. If unsure, say N.
187
188config SERIAL_8250_MANY_PORTS
189	bool "Support more than 4 legacy serial ports"
190	depends on SERIAL_8250_EXTENDED && !IA64
191	help
192	  Say Y here if you have dumb serial boards other than the four
193	  standard COM 1/2/3/4 ports. This may happen if you have an AST
194	  FourPort, Accent Async, Boca (read the Boca mini-HOWTO, available
195	  from <http://www.tldp.org/docs.html#howto>), or other custom
196	  serial port hardware which acts similar to standard serial port
197	  hardware. If you only use the standard COM 1/2/3/4 ports, you can
198	  say N here to save some memory. You can also say Y if you have an
199	  "intelligent" multiport card such as Cyclades, Digiboards, etc.
200
201#
202# Multi-port serial cards
203#
204
205config SERIAL_8250_FOURPORT
206	tristate "Support Fourport cards"
207	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
208	help
209	  Say Y here if you have an AST FourPort serial board.
210
211	  To compile this driver as a module, choose M here: the module
212	  will be called 8250_fourport.
213
214config SERIAL_8250_ACCENT
215	tristate "Support Accent cards"
216	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
217	help
218	  Say Y here if you have an Accent Async serial board.
219
220	  To compile this driver as a module, choose M here: the module
221	  will be called 8250_accent.
222
223config SERIAL_8250_BOCA
224	tristate "Support Boca cards"
225	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
226	help
227	  Say Y here if you have a Boca serial board.  Please read the Boca
228	  mini-HOWTO, available from <http://www.tldp.org/docs.html#howto>
229
230	  To compile this driver as a module, choose M here: the module
231	  will be called 8250_boca.
232
233config SERIAL_8250_EXAR_ST16C554
234	tristate "Support Exar ST16C554/554D Quad UART"
235	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
236	help
237	  The Uplogix Envoy TU301 uses this Exar Quad UART.  If you are
238	  tinkering with your Envoy TU301, or have a machine with this UART,
239	  say Y here.
240
241	  To compile this driver as a module, choose M here: the module
242	  will be called 8250_exar_st16c554.
243
244config SERIAL_8250_HUB6
245	tristate "Support Hub6 cards"
246	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
247	help
248	  Say Y here if you have a HUB6 serial board.
249
250	  To compile this driver as a module, choose M here: the module
251	  will be called 8250_hub6.
252
253#
254# Misc. options/drivers.
255#
256
257config SERIAL_8250_SHARE_IRQ
258	bool "Support for sharing serial interrupts"
259	depends on SERIAL_8250_EXTENDED
260	help
261	  Some serial boards have hardware support which allows multiple dumb
262	  serial ports on the same board to share a single IRQ. To enable
263	  support for this in the serial driver, say Y here.
264
265config SERIAL_8250_DETECT_IRQ
266	bool "Autodetect IRQ on standard ports (unsafe)"
267	depends on SERIAL_8250_EXTENDED
268	help
269	  Say Y here if you want the kernel to try to guess which IRQ
270	  to use for your serial port.
271
272	  This is considered unsafe; it is far better to configure the IRQ in
273	  a boot script using the setserial command.
274
275	  If unsure, say N.
276
277config SERIAL_8250_RSA
278	bool "Support RSA serial ports"
279	depends on SERIAL_8250_EXTENDED
280	help
281	  Say Y here if you have a IODATA RSA-DV II/S ISA card and
282	  would like to use its >115kbps speeds.
283	  You will need to provide module parameter "probe_rsa", or boot-time
284	  parameter 8250.probe_rsa with I/O addresses of this card then.
285
286	  If you don't have such card, or if unsure, say N.
287
288config SERIAL_8250_ACORN
289	tristate "Acorn expansion card serial port support"
290	depends on ARCH_ACORN && SERIAL_8250
291	help
292	  If you have an Atomwide Serial card or Serial Port card for an Acorn
293	  system, say Y to this option.  The driver can handle 1, 2, or 3 port
294	  cards.  If unsure, say N.
295
296config SERIAL_8250_BCM2835AUX
297	tristate "BCM2835 auxiliar mini UART support"
298	depends on ARCH_BCM2835 || COMPILE_TEST
299	depends on SERIAL_8250 && SERIAL_8250_SHARE_IRQ
300	help
301	  Support for the BCM2835 auxiliar mini UART.
302
303	  Features and limitations of the UART are
304	    Registers are similar to 16650 registers,
305              set bits in the control registers that are unsupported
306	      are ignored and read back as 0
307	    7/8 bit operation with 1 start and 1 stop bit
308	    8 symbols deep fifo for rx and tx
309	    SW controlled RTS and SW readable CTS
310	    Clock rate derived from system clock
311	    Uses 8 times oversampling (compared to 16 times for 16650)
312	    Missing break detection (but break generation)
313	    Missing framing error detection
314	    Missing parity bit
315	    Missing receive time-out interrupt
316	    Missing DCD, DSR, DTR and RI signals
317
318	  If unsure, say N.
319
320config SERIAL_8250_FSL
321	bool
322	depends on SERIAL_8250_CONSOLE
323	default PPC || ARM || ARM64
324
325config SERIAL_8250_DW
326	tristate "Support for Synopsys DesignWare 8250 quirks"
327	depends on SERIAL_8250
328	help
329	  Selecting this option will enable handling of the extra features
330	  present in the Synopsys DesignWare APB UART.
331
332config SERIAL_8250_EM
333	tristate "Support for Emma Mobile integrated serial port"
334	depends on SERIAL_8250 && ARM && HAVE_CLK
335	help
336	  Selecting this option will add support for the integrated serial
337	  port hardware found on the Emma Mobile line of processors.
338	  If unsure, say N.
339
340config SERIAL_8250_RT288X
341	bool "Ralink RT288x/RT305x/RT3662/RT3883 serial port support"
342	depends on SERIAL_8250
343	default y if MIPS_ALCHEMY || SOC_RT288X || SOC_RT305X || SOC_RT3883 || SOC_MT7620
344	help
345	  Selecting this option will add support for the alternate register
346	  layout used by Ralink RT288x/RT305x, Alchemy Au1xxx, and some others.
347	  If unsure, say N.
348
349config SERIAL_8250_OMAP
350	tristate "Support for OMAP internal UART (8250 based driver)"
351	depends on SERIAL_8250 && ARCH_OMAP2PLUS
352	help
353	  If you have a machine based on an Texas Instruments OMAP CPU you
354	  can enable its onboard serial ports by enabling this option.
355
356	  This driver uses ttyS instead of ttyO.
357
358config SERIAL_8250_OMAP_TTYO_FIXUP
359	bool "Replace ttyO with ttyS"
360	depends on SERIAL_8250_OMAP=y && SERIAL_8250_CONSOLE
361	default y
362	help
363	  This option replaces the "console=ttyO" argument with the matching
364	  ttyS argument if the user did not specified it on the command line.
365	  This ensures that the user can see the kernel output during boot
366	  which he wouldn't see otherwise. The getty has still to be configured
367	  for ttyS instead of ttyO regardless of this option.
368	  This option is intended for people who "automatically" enable this
369	  driver without knowing that this driver requires a different console=
370	  argument. If you read this, please keep this option disabled and
371	  instead update your kernel command line. If you prepare a kernel for a
372	  distribution or other kind of larger user base then you probably want
373	  to keep this option enabled. Otherwise people might complain about a
374	  not booting kernel because the serial console remains silent in case
375	  they forgot to update the command line.
376
377config SERIAL_8250_LPC18XX
378	tristate "NXP LPC18xx/43xx serial port support"
379	depends on SERIAL_8250 && OF && (ARCH_LPC18XX || COMPILE_TEST)
380	default ARCH_LPC18XX
381	help
382	  If you have a LPC18xx/43xx based board and want to use the
383	  serial port, say Y to this option. If unsure, say Y.
384
385config SERIAL_8250_MT6577
386	tristate "Mediatek serial port support"
387	depends on SERIAL_8250 && ARCH_MEDIATEK
388	help
389	  If you have a Mediatek based board and want to use the
390	  serial port, say Y to this option. If unsure, say N.
391
392config SERIAL_8250_UNIPHIER
393	tristate "Support for UniPhier on-chip UART"
394	depends on SERIAL_8250
395	depends on ARCH_UNIPHIER || COMPILE_TEST
396	help
397	  If you have a UniPhier based board and want to use the on-chip
398	  serial ports, say Y to this option. If unsure, say N.
399
400config SERIAL_8250_INGENIC
401	tristate "Support for Ingenic SoC serial ports"
402	depends on SERIAL_8250
403	depends on OF_FLATTREE
404	depends on MIPS || COMPILE_TEST
405	help
406	  If you have a system using an Ingenic SoC and wish to make use of
407	  its UARTs, say Y to this option. If unsure, say N.
408
409config SERIAL_8250_LPSS
410	tristate "Support for serial ports on Intel LPSS platforms"
411	default SERIAL_8250
412	depends on SERIAL_8250 && PCI
413	depends on X86 || COMPILE_TEST
414	select DW_DMAC_CORE if SERIAL_8250_DMA
415	select DW_DMAC_PCI if (SERIAL_8250_DMA && X86_INTEL_LPSS)
416	select RATIONAL
417	help
418	  Selecting this option will enable handling of the extra features
419	  present on the UART found on various Intel platforms such as:
420	    - Intel Baytrail SoC
421	    - Intel Braswell SoC
422	    - Intel Quark X1000 SoC
423
424config SERIAL_8250_MID
425	tristate "Support for serial ports on Intel MID platforms"
426	default SERIAL_8250
427	depends on SERIAL_8250 && PCI
428	depends on X86 || COMPILE_TEST
429	select HSU_DMA if SERIAL_8250_DMA
430	select HSU_DMA_PCI if (HSU_DMA && X86_INTEL_MID)
431	select RATIONAL
432	help
433	  Selecting this option will enable handling of the extra features
434	  present on the UART found on Intel Medfield SOC and various other
435	  Intel platforms.
436
437config SERIAL_8250_MOXA
438	tristate "MOXA SmartIO MUE support"
439	depends on SERIAL_8250 && PCI
440	help
441	  Say Y here if you have a Moxa SmartIO MUE multiport serial card.
442	  If unsure, say N.
443
444	  This driver can also be built as a module. The module will be called
445	  8250_moxa. If you want to do that, say M here.
446
447config SERIAL_8250_PXA
448	tristate "PXA serial port support"
449	depends on SERIAL_8250
450	depends on ARCH_PXA || ARCH_MMP
451	help
452	  If you have a machine based on an Intel XScale PXA2xx CPU you can
453	  enable its onboard serial ports by enabling this option. The option is
454	  applicable to both devicetree and legacy boards, and early console is
455	  part of its support.
456
457config SERIAL_OF_PLATFORM
458	tristate "Devicetree based probing for 8250 ports"
459	depends on SERIAL_8250 && OF
460	help
461	  This option is used for all 8250 compatible serial ports that
462	  are probed through devicetree, including Open Firmware based
463	  PowerPC systems and embedded systems on architectures using the
464	  flattened device tree format.
465