xref: /openbmc/linux/drivers/tty/serial/8250/Kconfig (revision a9a08845)
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 Z125 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 Z125 UARTs.
165
166	  To compile this driver as a module, chose M here: the
167	  module will be called 8250_men_mcb.
168
169
170config SERIAL_8250_NR_UARTS
171	int "Maximum number of 8250/16550 serial ports"
172	depends on SERIAL_8250
173	default "4"
174	help
175	  Set this to the number of serial ports you want the driver
176	  to support.  This includes any ports discovered via ACPI or
177	  PCI enumeration and any ports that may be added at run-time
178	  via hot-plug, or any ISA multi-port serial cards.
179
180config SERIAL_8250_RUNTIME_UARTS
181	int "Number of 8250/16550 serial ports to register at runtime"
182	depends on SERIAL_8250
183	range 0 SERIAL_8250_NR_UARTS
184	default "4"
185	help
186	  Set this to the maximum number of serial ports you want
187	  the kernel to register at boot time.  This can be overridden
188	  with the module parameter "nr_uarts", or boot-time parameter
189	  8250.nr_uarts
190
191config SERIAL_8250_EXTENDED
192	bool "Extended 8250/16550 serial driver options"
193	depends on SERIAL_8250
194	help
195	  If you wish to use any non-standard features of the standard "dumb"
196	  driver, say Y here. This includes HUB6 support, shared serial
197	  interrupts, special multiport support, support for more than the
198	  four COM 1/2/3/4 boards, etc.
199
200	  Note that the answer to this question won't directly affect the
201	  kernel: saying N will just cause the configurator to skip all
202	  the questions about serial driver options. If unsure, say N.
203
204config SERIAL_8250_MANY_PORTS
205	bool "Support more than 4 legacy serial ports"
206	depends on SERIAL_8250_EXTENDED && !IA64
207	help
208	  Say Y here if you have dumb serial boards other than the four
209	  standard COM 1/2/3/4 ports. This may happen if you have an AST
210	  FourPort, Accent Async, Boca (read the Boca mini-HOWTO, available
211	  from <http://www.tldp.org/docs.html#howto>), or other custom
212	  serial port hardware which acts similar to standard serial port
213	  hardware. If you only use the standard COM 1/2/3/4 ports, you can
214	  say N here to save some memory. You can also say Y if you have an
215	  "intelligent" multiport card such as Cyclades, Digiboards, etc.
216
217#
218# Multi-port serial cards
219#
220
221config SERIAL_8250_FOURPORT
222	tristate "Support Fourport cards"
223	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
224	help
225	  Say Y here if you have an AST FourPort serial board.
226
227	  To compile this driver as a module, choose M here: the module
228	  will be called 8250_fourport.
229
230config SERIAL_8250_ACCENT
231	tristate "Support Accent cards"
232	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
233	help
234	  Say Y here if you have an Accent Async serial board.
235
236	  To compile this driver as a module, choose M here: the module
237	  will be called 8250_accent.
238
239config SERIAL_8250_ASPEED_VUART
240	tristate "Aspeed Virtual UART"
241	depends on SERIAL_8250
242	depends on OF
243	help
244	  If you want to use the virtual UART (VUART) device on Aspeed
245	  BMC platforms, enable this option. This enables the 16550A-
246	  compatible device on the local LPC bus, giving a UART device
247	  with no physical RS232 connections.
248
249config SERIAL_8250_BOCA
250	tristate "Support Boca cards"
251	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
252	help
253	  Say Y here if you have a Boca serial board.  Please read the Boca
254	  mini-HOWTO, available from <http://www.tldp.org/docs.html#howto>
255
256	  To compile this driver as a module, choose M here: the module
257	  will be called 8250_boca.
258
259config SERIAL_8250_EXAR_ST16C554
260	tristate "Support Exar ST16C554/554D Quad UART"
261	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
262	help
263	  The Uplogix Envoy TU301 uses this Exar Quad UART.  If you are
264	  tinkering with your Envoy TU301, or have a machine with this UART,
265	  say Y here.
266
267	  To compile this driver as a module, choose M here: the module
268	  will be called 8250_exar_st16c554.
269
270config SERIAL_8250_HUB6
271	tristate "Support Hub6 cards"
272	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
273	help
274	  Say Y here if you have a HUB6 serial board.
275
276	  To compile this driver as a module, choose M here: the module
277	  will be called 8250_hub6.
278
279#
280# Misc. options/drivers.
281#
282
283config SERIAL_8250_SHARE_IRQ
284	bool "Support for sharing serial interrupts"
285	depends on SERIAL_8250_EXTENDED
286	help
287	  Some serial boards have hardware support which allows multiple dumb
288	  serial ports on the same board to share a single IRQ. To enable
289	  support for this in the serial driver, say Y here.
290
291config SERIAL_8250_DETECT_IRQ
292	bool "Autodetect IRQ on standard ports (unsafe)"
293	depends on SERIAL_8250_EXTENDED
294	help
295	  Say Y here if you want the kernel to try to guess which IRQ
296	  to use for your serial port.
297
298	  This is considered unsafe; it is far better to configure the IRQ in
299	  a boot script using the setserial command.
300
301	  If unsure, say N.
302
303config SERIAL_8250_RSA
304	bool "Support RSA serial ports"
305	depends on SERIAL_8250_EXTENDED
306	help
307	  Say Y here if you have a IODATA RSA-DV II/S ISA card and
308	  would like to use its >115kbps speeds.
309	  You will need to provide module parameter "probe_rsa", or boot-time
310	  parameter 8250.probe_rsa with I/O addresses of this card then.
311
312	  If you don't have such card, or if unsure, say N.
313
314config SERIAL_8250_ACORN
315	tristate "Acorn expansion card serial port support"
316	depends on ARCH_ACORN && SERIAL_8250
317	help
318	  If you have an Atomwide Serial card or Serial Port card for an Acorn
319	  system, say Y to this option.  The driver can handle 1, 2, or 3 port
320	  cards.  If unsure, say N.
321
322config SERIAL_8250_BCM2835AUX
323	tristate "BCM2835 auxiliar mini UART support"
324	depends on ARCH_BCM2835 || COMPILE_TEST
325	depends on SERIAL_8250 && SERIAL_8250_SHARE_IRQ
326	help
327	  Support for the BCM2835 auxiliar mini UART.
328
329	  Features and limitations of the UART are
330	    Registers are similar to 16650 registers,
331              set bits in the control registers that are unsupported
332	      are ignored and read back as 0
333	    7/8 bit operation with 1 start and 1 stop bit
334	    8 symbols deep fifo for rx and tx
335	    SW controlled RTS and SW readable CTS
336	    Clock rate derived from system clock
337	    Uses 8 times oversampling (compared to 16 times for 16650)
338	    Missing break detection (but break generation)
339	    Missing framing error detection
340	    Missing parity bit
341	    Missing receive time-out interrupt
342	    Missing DCD, DSR, DTR and RI signals
343
344	  If unsure, say N.
345
346config SERIAL_8250_FSL
347	bool
348	depends on SERIAL_8250_CONSOLE
349	default PPC || ARM || ARM64
350
351config SERIAL_8250_DW
352	tristate "Support for Synopsys DesignWare 8250 quirks"
353	depends on SERIAL_8250
354	help
355	  Selecting this option will enable handling of the extra features
356	  present in the Synopsys DesignWare APB UART.
357
358config SERIAL_8250_EM
359	tristate "Support for Emma Mobile integrated serial port"
360	depends on SERIAL_8250 && ARM && HAVE_CLK
361	help
362	  Selecting this option will add support for the integrated serial
363	  port hardware found on the Emma Mobile line of processors.
364	  If unsure, say N.
365
366config SERIAL_8250_RT288X
367	bool "Ralink RT288x/RT305x/RT3662/RT3883 serial port support"
368	depends on SERIAL_8250
369	default y if MIPS_ALCHEMY || SOC_RT288X || SOC_RT305X || SOC_RT3883 || SOC_MT7620
370	help
371	  Selecting this option will add support for the alternate register
372	  layout used by Ralink RT288x/RT305x, Alchemy Au1xxx, and some others.
373	  If unsure, say N.
374
375config SERIAL_8250_OMAP
376	tristate "Support for OMAP internal UART (8250 based driver)"
377	depends on SERIAL_8250 && ARCH_OMAP2PLUS
378	help
379	  If you have a machine based on an Texas Instruments OMAP CPU you
380	  can enable its onboard serial ports by enabling this option.
381
382	  This driver uses ttyS instead of ttyO.
383
384config SERIAL_8250_OMAP_TTYO_FIXUP
385	bool "Replace ttyO with ttyS"
386	depends on SERIAL_8250_OMAP=y && SERIAL_8250_CONSOLE
387	default y
388	help
389	  This option replaces the "console=ttyO" argument with the matching
390	  ttyS argument if the user did not specified it on the command line.
391	  This ensures that the user can see the kernel output during boot
392	  which he wouldn't see otherwise. The getty has still to be configured
393	  for ttyS instead of ttyO regardless of this option.
394	  This option is intended for people who "automatically" enable this
395	  driver without knowing that this driver requires a different console=
396	  argument. If you read this, please keep this option disabled and
397	  instead update your kernel command line. If you prepare a kernel for a
398	  distribution or other kind of larger user base then you probably want
399	  to keep this option enabled. Otherwise people might complain about a
400	  not booting kernel because the serial console remains silent in case
401	  they forgot to update the command line.
402
403config SERIAL_8250_LPC18XX
404	tristate "NXP LPC18xx/43xx serial port support"
405	depends on SERIAL_8250 && OF && (ARCH_LPC18XX || COMPILE_TEST)
406	default ARCH_LPC18XX
407	help
408	  If you have a LPC18xx/43xx based board and want to use the
409	  serial port, say Y to this option. If unsure, say Y.
410
411config SERIAL_8250_MT6577
412	tristate "Mediatek serial port support"
413	depends on SERIAL_8250 && ARCH_MEDIATEK
414	help
415	  If you have a Mediatek based board and want to use the
416	  serial port, say Y to this option. If unsure, say N.
417
418config SERIAL_8250_UNIPHIER
419	tristate "Support for UniPhier on-chip UART"
420	depends on SERIAL_8250
421	depends on ARCH_UNIPHIER || COMPILE_TEST
422	help
423	  If you have a UniPhier based board and want to use the on-chip
424	  serial ports, say Y to this option. If unsure, say N.
425
426config SERIAL_8250_INGENIC
427	tristate "Support for Ingenic SoC serial ports"
428	depends on SERIAL_8250
429	depends on OF_FLATTREE
430	depends on MIPS || COMPILE_TEST
431	help
432	  If you have a system using an Ingenic SoC and wish to make use of
433	  its UARTs, say Y to this option. If unsure, say N.
434
435config SERIAL_8250_LPSS
436	tristate "Support for serial ports on Intel LPSS platforms"
437	default SERIAL_8250
438	depends on SERIAL_8250 && PCI
439	depends on X86 || COMPILE_TEST
440	select DW_DMAC_CORE if SERIAL_8250_DMA
441	select DW_DMAC_PCI if (SERIAL_8250_DMA && X86_INTEL_LPSS)
442	select RATIONAL
443	help
444	  Selecting this option will enable handling of the extra features
445	  present on the UART found on various Intel platforms such as:
446	    - Intel Baytrail SoC
447	    - Intel Braswell SoC
448	    - Intel Quark X1000 SoC
449
450config SERIAL_8250_MID
451	tristate "Support for serial ports on Intel MID platforms"
452	default SERIAL_8250
453	depends on SERIAL_8250 && PCI
454	depends on X86 || COMPILE_TEST
455	select HSU_DMA if SERIAL_8250_DMA
456	select HSU_DMA_PCI if (HSU_DMA && X86_INTEL_MID)
457	select RATIONAL
458	help
459	  Selecting this option will enable handling of the extra features
460	  present on the UART found on Intel Medfield SOC and various other
461	  Intel platforms.
462
463config SERIAL_8250_MOXA
464	tristate "MOXA SmartIO MUE support"
465	depends on SERIAL_8250 && PCI
466	help
467	  Say Y here if you have a Moxa SmartIO MUE multiport serial card.
468	  If unsure, say N.
469
470	  This driver can also be built as a module. The module will be called
471	  8250_moxa. If you want to do that, say M here.
472
473config SERIAL_8250_PXA
474	tristate "PXA serial port support"
475	depends on SERIAL_8250
476	depends on ARCH_PXA || ARCH_MMP
477	help
478	  If you have a machine based on an Intel XScale PXA2xx CPU you can
479	  enable its onboard serial ports by enabling this option. The option is
480	  applicable to both devicetree and legacy boards, and early console is
481	  part of its support.
482
483config SERIAL_OF_PLATFORM
484	tristate "Devicetree based probing for 8250 ports"
485	depends on SERIAL_8250 && OF
486	help
487	  This option is used for all 8250 compatible serial ports that
488	  are probed through devicetree, including Open Firmware based
489	  PowerPC systems and embedded systems on architectures using the
490	  flattened device tree format.
491