Kconfig 21 KB

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  1. # SPDX-License-Identifier: GPL-2.0
  2. #
  3. # The 8250/16550 serial drivers. You shouldn't be in this list unless
  4. # you somehow have an implicit or explicit dependency on SERIAL_8250.
  5. #
  6. config SERIAL_8250
  7. tristate "8250/16550 and compatible serial support"
  8. depends on !S390
  9. select SERIAL_CORE
  10. select SERIAL_MCTRL_GPIO if GPIOLIB
  11. help
  12. This selects whether you want to include the driver for the standard
  13. serial ports. The standard answer is Y. People who might say N
  14. here are those that are setting up dedicated Ethernet WWW/FTP
  15. servers, or users that have one of the various bus mice instead of a
  16. serial mouse and don't intend to use their machine's standard serial
  17. port for anything.
  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. BTW1: If you have a mouseman serial mouse which is not recognized by
  25. the X window system, try running gpm first.
  26. BTW2: If you intend to use a software modem (also called Winmodem)
  27. under Linux, forget it. These modems are crippled and require
  28. proprietary drivers which are only available under Windows.
  29. Most people will say Y or M here, so that they can use serial mice,
  30. modems and similar devices connecting to the standard serial ports.
  31. config SERIAL_8250_PNP
  32. bool "8250/16550 PNP device support" if EXPERT
  33. depends on SERIAL_8250 && PNP
  34. default y
  35. help
  36. This builds standard PNP serial support. You may be able to
  37. disable this feature if you only need legacy serial support.
  38. config SERIAL_8250_16550A_VARIANTS
  39. bool "Support for variants of the 16550A serial port"
  40. depends on SERIAL_8250
  41. default !X86
  42. help
  43. The 8250 driver can probe for many variants of the venerable 16550A
  44. serial port. Doing so takes additional time at boot.
  45. On modern systems, especially those using serial only for a simple
  46. console, you can say N here.
  47. config SERIAL_8250_FINTEK
  48. bool "Support for Fintek variants"
  49. depends on SERIAL_8250 && HAS_IOPORT
  50. help
  51. Selecting this option will add support for the RS232 and RS485
  52. capabilities of the Fintek F81216A LPC to 4 UART as well similar
  53. variants.
  54. If this option is not selected the device will be configured as a
  55. standard 16550A serial port, however the device may not function
  56. correctly without this option enabled.
  57. If unsure, say N.
  58. config SERIAL_8250_CONSOLE
  59. bool "Console on 8250/16550 and compatible serial port"
  60. depends on SERIAL_8250=y
  61. select SERIAL_CORE_CONSOLE
  62. select SERIAL_EARLYCON
  63. help
  64. If you say Y here, it will be possible to use a serial port as the
  65. system console (the system console is the device which receives all
  66. kernel messages and warnings and which allows logins in single user
  67. mode). This could be useful if some terminal or printer is connected
  68. to that serial port.
  69. Even if you say Y here, the currently visible virtual console
  70. (/dev/tty0) will still be used as the system console by default, but
  71. you can alter that using a kernel command line option such as
  72. "console=ttyS1". (Try "man bootparam" or see the documentation of
  73. your boot loader (grub or lilo or loadlin) about how to pass options
  74. to the kernel at boot time.)
  75. If you don't have a VGA card installed and you say Y here, the
  76. kernel will automatically use the first serial line, /dev/ttyS0, as
  77. system console.
  78. You can set that using a kernel command line option such as
  79. "console=uart8250,io,0x3f8,9600n8"
  80. "console=uart8250,mmio,0xff5e0000,115200n8".
  81. and it will switch to normal serial console when the corresponding
  82. port is ready.
  83. "earlycon=uart8250,io,0x3f8,9600n8"
  84. "earlycon=uart8250,mmio,0xff5e0000,115200n8".
  85. it will not only setup early console.
  86. If unsure, say N.
  87. config SERIAL_8250_PARISC
  88. tristate
  89. depends on SERIAL_8250 && PARISC
  90. default SERIAL_8250
  91. config SERIAL_8250_DMA
  92. bool "DMA support for 16550 compatible UART controllers" if EXPERT
  93. depends on SERIAL_8250 && DMADEVICES=y
  94. default SERIAL_8250
  95. help
  96. This builds DMA support that can be used with 8250/16650
  97. compatible UART controllers that support DMA signaling.
  98. config SERIAL_8250_PCILIB
  99. bool
  100. depends on SERIAL_8250 && PCI
  101. config SERIAL_8250_PCI
  102. tristate "8250/16550 PCI device support"
  103. depends on SERIAL_8250 && PCI
  104. select SERIAL_8250_PCILIB
  105. default SERIAL_8250
  106. help
  107. This builds standard PCI serial support. You may be able to
  108. disable this feature if you only need legacy serial support.
  109. Saves about 9K.
  110. Note that serial ports on NetMos 9835 Multi-I/O cards are handled
  111. by the parport_serial driver, enabled with CONFIG_PARPORT_SERIAL.
  112. config SERIAL_8250_EXAR
  113. tristate "8250/16550 Exar/Commtech PCI/PCIe device support"
  114. depends on SERIAL_8250 && PCI
  115. select SERIAL_8250_PCILIB
  116. select EEPROM_93CX6
  117. default SERIAL_8250
  118. help
  119. This builds support for XR17C1xx, XR17V3xx and some Commtech
  120. 422x PCIe serial cards that are not covered by the more generic
  121. SERIAL_8250_PCI option.
  122. config SERIAL_8250_HP300
  123. tristate
  124. depends on SERIAL_8250 && HP300
  125. default SERIAL_8250
  126. config SERIAL_8250_CS
  127. tristate "8250/16550 PCMCIA device support"
  128. depends on PCMCIA && SERIAL_8250 && HAS_IOPORT
  129. help
  130. Say Y here to enable support for 16-bit PCMCIA serial devices,
  131. including serial port cards, modems, and the modem functions of
  132. multi-function Ethernet/modem cards. (PCMCIA- or PC-cards are
  133. credit-card size devices often used with laptops.)
  134. To compile this driver as a module, choose M here: the
  135. module will be called serial_cs.
  136. If unsure, say N.
  137. config SERIAL_8250_MEN_MCB
  138. tristate "MEN MCB UART device support"
  139. depends on MCB && SERIAL_8250
  140. help
  141. This enables support for FPGA based UARTs found on many MEN
  142. boards. This driver enables support for the 16z025, 16z057
  143. and 16z125 UARTs.
  144. To compile this driver as a module, chose M here: the
  145. module will be called 8250_men_mcb.
  146. config SERIAL_8250_NR_UARTS
  147. int "Maximum number of 8250/16550 serial ports"
  148. depends on SERIAL_8250
  149. default "4"
  150. help
  151. Set this to the number of serial ports you want the driver
  152. to support. This includes any ports discovered via ACPI or
  153. PCI enumeration and any ports that may be added at run-time
  154. via hot-plug, or any ISA multi-port serial cards.
  155. config SERIAL_8250_RUNTIME_UARTS
  156. int "Number of 8250/16550 serial ports to register at runtime"
  157. depends on SERIAL_8250
  158. range 0 SERIAL_8250_NR_UARTS
  159. default "4"
  160. help
  161. Set this to the maximum number of serial ports you want
  162. the kernel to register at boot time. This can be overridden
  163. with the module parameter "nr_uarts", or boot-time parameter
  164. 8250.nr_uarts
  165. config SERIAL_8250_EXTENDED
  166. bool "Extended 8250/16550 serial driver options"
  167. depends on SERIAL_8250
  168. help
  169. If you wish to use any non-standard features of the standard "dumb"
  170. driver, say Y here. This includes HUB6 support, shared serial
  171. interrupts, special multiport support, support for more than the
  172. four COM 1/2/3/4 boards, etc.
  173. Note that the answer to this question won't directly affect the
  174. kernel: saying N will just cause the configurator to skip all
  175. the questions about serial driver options. If unsure, say N.
  176. config SERIAL_8250_SHARE_IRQ
  177. bool "Support for sharing serial interrupts"
  178. depends on SERIAL_8250_EXTENDED
  179. help
  180. Some serial boards have hardware support which allows multiple dumb
  181. serial ports on the same board to share a single IRQ. To enable
  182. support for this in the serial driver, say Y here.
  183. config SERIAL_8250_DETECT_IRQ
  184. bool "Autodetect IRQ on standard ports (unsafe)"
  185. depends on SERIAL_8250_EXTENDED
  186. help
  187. Say Y here if you want the kernel to try to guess which IRQ
  188. to use for your serial port.
  189. This is considered unsafe; it is far better to configure the IRQ in
  190. a boot script using the setserial command.
  191. If unsure, say N.
  192. config SERIAL_8250_RSA
  193. bool "Support RSA serial ports"
  194. depends on SERIAL_8250_EXTENDED
  195. help
  196. Say Y here if you have a IODATA RSA-DV II/S ISA card and
  197. would like to use its >115kbps speeds.
  198. You will need to provide module parameter "probe_rsa", or boot-time
  199. parameter 8250.probe_rsa with I/O addresses of this card then.
  200. If you don't have such card, or if unsure, say N.
  201. config SERIAL_8250_MANY_PORTS
  202. bool "Support more than 4 legacy serial ports"
  203. depends on SERIAL_8250_EXTENDED
  204. help
  205. Say Y here if you have dumb serial boards other than the four
  206. standard COM 1/2/3/4 ports. This may happen if you have an AST
  207. FourPort, Accent Async, Boca (read the Boca mini-HOWTO, available
  208. from <https://www.tldp.org/docs.html#howto>), or other custom
  209. serial port hardware which acts similar to standard serial port
  210. hardware. If you only use the standard COM 1/2/3/4 ports, you can
  211. say N here to save some memory. You can also say Y if you have an
  212. "intelligent" multiport card such as Digiboards, etc.
  213. #
  214. # Multi-port serial cards
  215. #
  216. config SERIAL_8250_FOURPORT
  217. tristate "Support Fourport cards"
  218. depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
  219. help
  220. Say Y here if you have an AST FourPort serial board.
  221. To compile this driver as a module, choose M here: the module
  222. will be called 8250_fourport.
  223. config SERIAL_8250_ACCENT
  224. tristate "Support Accent cards"
  225. depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
  226. help
  227. Say Y here if you have an Accent Async serial board.
  228. To compile this driver as a module, choose M here: the module
  229. will be called 8250_accent.
  230. config SERIAL_8250_BOCA
  231. tristate "Support Boca cards"
  232. depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
  233. help
  234. Say Y here if you have a Boca serial board. Please read the Boca
  235. mini-HOWTO, available from <https://www.tldp.org/docs.html#howto>
  236. To compile this driver as a module, choose M here: the module
  237. will be called 8250_boca.
  238. config SERIAL_8250_EXAR_ST16C554
  239. tristate "Support Exar ST16C554/554D Quad UART"
  240. depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
  241. help
  242. The Uplogix Envoy TU301 uses this Exar Quad UART. If you are
  243. tinkering with your Envoy TU301, or have a machine with this UART,
  244. say Y here.
  245. To compile this driver as a module, choose M here: the module
  246. will be called 8250_exar_st16c554.
  247. config SERIAL_8250_HUB6
  248. tristate "Support Hub6 cards"
  249. depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
  250. help
  251. Say Y here if you have a HUB6 serial board.
  252. To compile this driver as a module, choose M here: the module
  253. will be called 8250_hub6.
  254. config SERIAL_8250_PCI1XXXX
  255. tristate "Microchip 8250 based serial port"
  256. depends on SERIAL_8250 && PCI
  257. select SERIAL_8250_PCILIB
  258. help
  259. Select this option if you have a setup with Microchip PCIe
  260. Switch with serial port enabled and wish to enable 8250
  261. serial driver for the serial interface. This driver support
  262. will ensure to support baud rates upto 1.5Mpbs.
  263. config SERIAL_8250_ASPEED_VUART
  264. tristate "Aspeed Virtual UART"
  265. depends on SERIAL_8250
  266. depends on OF
  267. depends on MFD_SYSCON
  268. depends on ARCH_ASPEED || COMPILE_TEST
  269. select REGMAP
  270. help
  271. If you want to use the virtual UART (VUART) device on Aspeed
  272. BMC platforms, enable this option. This enables the 16550A-
  273. compatible device on the local LPC bus, giving a UART device
  274. with no physical RS232 connections.
  275. #
  276. # Misc. options/drivers.
  277. #
  278. config SERIAL_8250_ACORN
  279. tristate "Acorn expansion card serial port support"
  280. depends on ARCH_ACORN && SERIAL_8250
  281. help
  282. If you have an Atomwide Serial card or Serial Port card for an Acorn
  283. system, say Y to this option. The driver can handle 1, 2, or 3 port
  284. cards. If unsure, say N.
  285. config SERIAL_8250_BCM2835AUX
  286. tristate "BCM2835 auxiliar mini UART support"
  287. depends on ARCH_BCM2835 || COMPILE_TEST
  288. depends on SERIAL_8250 && SERIAL_8250_SHARE_IRQ
  289. help
  290. Support for the BCM2835 auxiliar mini UART.
  291. Features and limitations of the UART are
  292. Registers are similar to 16650 registers,
  293. set bits in the control registers that are unsupported
  294. are ignored and read back as 0
  295. 7/8 bit operation with 1 start and 1 stop bit
  296. 8 symbols deep fifo for rx and tx
  297. SW controlled RTS and SW readable CTS
  298. Clock rate derived from system clock
  299. Uses 8 times oversampling (compared to 16 times for 16650)
  300. Missing break detection (but break generation)
  301. Missing framing error detection
  302. Missing parity bit
  303. Missing receive time-out interrupt
  304. Missing DCD, DSR, DTR and RI signals
  305. If unsure, say N.
  306. config SERIAL_8250_FSL
  307. tristate "Freescale 16550 UART support" if COMPILE_TEST && !(PPC || ARM || ARM64)
  308. depends on SERIAL_8250
  309. default SERIAL_8250 if PPC || ARM || ARM64
  310. help
  311. Selecting this option enables a workaround for a break-detection
  312. erratum for Freescale 16550 UARTs in the 8250 driver. It also
  313. enables support for ACPI enumeration.
  314. config SERIAL_8250_DFL
  315. tristate "DFL bus driver for Altera 16550 UART"
  316. depends on SERIAL_8250 && FPGA_DFL
  317. help
  318. This option enables support for a Device Feature List (DFL) bus
  319. driver for the Altera 16550 UART. One or more Altera 16550 UARTs
  320. can be instantiated in a FPGA and then be discovered during
  321. enumeration of the DFL bus.
  322. To compile this driver as a module, chose M here: the
  323. module will be called 8250_dfl.
  324. config SERIAL_8250_DW
  325. tristate "Support for Synopsys DesignWare 8250 quirks"
  326. depends on SERIAL_8250
  327. select SERIAL_8250_DWLIB
  328. help
  329. Selecting this option will enable handling of the extra features
  330. present in the Synopsys DesignWare APB UART.
  331. config SERIAL_8250_EM
  332. tristate "Support for Emma Mobile integrated serial port"
  333. depends on SERIAL_8250 && HAVE_CLK
  334. depends on ARCH_RENESAS || COMPILE_TEST
  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. config SERIAL_8250_IOC3
  340. tristate "SGI IOC3 8250 UART support"
  341. depends on SERIAL_8250
  342. depends on SGI_MFD_IOC3 || COMPILE_TEST
  343. select SERIAL_8250_EXTENDED
  344. select SERIAL_8250_SHARE_IRQ
  345. help
  346. Enable this if you have a SGI Origin or Octane machine. This module
  347. provides basic serial support by directly driving the UART chip
  348. behind the IOC3 device on those systems. Maximum baud speed is
  349. 38400bps using this driver.
  350. config SERIAL_8250_KEBA
  351. tristate "Support for KEBA 8250 UART"
  352. depends on SERIAL_8250
  353. depends on KEBA_CP500
  354. help
  355. Selecting this option will add support for KEBA UARTs. These UARTs
  356. are used for the serial interfaces of KEBA PLCs.
  357. This driver can also be built as a module. If so, the module will
  358. be called 8250_keba.
  359. If unsure, say N.
  360. config SERIAL_8250_RT288X
  361. bool "Ralink RT288x/RT305x/RT3662/RT3883 serial port support"
  362. depends on SERIAL_8250
  363. default y if MIPS_ALCHEMY || SOC_RT288X || SOC_RT305X || SOC_RT3883 || SOC_MT7620
  364. help
  365. Selecting this option will add support for the alternate register
  366. layout used by Ralink RT288x/RT305x, Alchemy Au1xxx, and some others.
  367. If unsure, say N.
  368. config SERIAL_8250_OMAP
  369. tristate "Support for OMAP internal UART (8250 based driver)"
  370. depends on SERIAL_8250
  371. depends on ARCH_OMAP2PLUS || ARCH_K3 || COMPILE_TEST
  372. help
  373. If you have a machine based on an Texas Instruments OMAP CPU you
  374. can enable its onboard serial ports by enabling this option.
  375. This driver uses ttyS instead of ttyO.
  376. config SERIAL_8250_OMAP_TTYO_FIXUP
  377. bool "Replace ttyO with ttyS"
  378. depends on SERIAL_8250_OMAP=y && SERIAL_8250_CONSOLE
  379. default y
  380. help
  381. This option replaces the "console=ttyO" argument with the matching
  382. ttyS argument if the user did not specified it on the command line.
  383. This ensures that the user can see the kernel output during boot
  384. which he wouldn't see otherwise. The getty has still to be configured
  385. for ttyS instead of ttyO regardless of this option.
  386. This option is intended for people who "automatically" enable this
  387. driver without knowing that this driver requires a different console=
  388. argument. If you read this, please keep this option disabled and
  389. instead update your kernel command line. If you prepare a kernel for a
  390. distribution or other kind of larger user base then you probably want
  391. to keep this option enabled. Otherwise people might complain about a
  392. not booting kernel because the serial console remains silent in case
  393. they forgot to update the command line.
  394. config SERIAL_8250_LOONGSON
  395. tristate "Loongson 8250 based serial port"
  396. depends on SERIAL_8250
  397. depends on LOONGARCH || COMPILE_TEST
  398. help
  399. If you have a machine based on LoongArch CPU you can enable
  400. its onboard serial ports by enabling this option. The option
  401. is applicable to both devicetree and ACPI, say Y to this option.
  402. If unsure, say N.
  403. config 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. config SERIAL_8250_MT6577
  411. tristate "Mediatek serial port support"
  412. depends on SERIAL_8250
  413. depends on ARCH_MEDIATEK || COMPILE_TEST
  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. config 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. config SERIAL_8250_INGENIC
  425. tristate "Support for Ingenic SoC serial ports"
  426. depends on SERIAL_8250
  427. depends on OF_FLATTREE
  428. depends on MIPS || COMPILE_TEST
  429. help
  430. If you have a system using an Ingenic SoC and wish to make use of
  431. its UARTs, say Y to this option. If unsure, say N.
  432. config SERIAL_8250_LPSS
  433. tristate "Support for serial ports on Intel LPSS platforms"
  434. default SERIAL_8250
  435. depends on SERIAL_8250 && PCI
  436. depends on X86 || COMPILE_TEST
  437. select SERIAL_8250_DWLIB
  438. select DW_DMAC_CORE if SERIAL_8250_DMA
  439. select DW_DMAC_PCI if (SERIAL_8250_DMA && X86_INTEL_LPSS)
  440. select RATIONAL
  441. help
  442. Selecting this option will enable handling of the UART found on
  443. various Intel platforms such as:
  444. - Intel Baytrail SoC
  445. - Intel Braswell SoC
  446. - Intel Quark X1000 SoC
  447. that are not covered by the more generic SERIAL_8250_PCI option.
  448. config SERIAL_8250_MID
  449. tristate "Support for serial ports on Intel MID platforms"
  450. default SERIAL_8250
  451. depends on SERIAL_8250 && PCI
  452. depends on X86 || COMPILE_TEST
  453. select HSU_DMA if SERIAL_8250_DMA
  454. select HSU_DMA_PCI if (HSU_DMA && X86_INTEL_MID)
  455. select RATIONAL
  456. help
  457. Selecting this option will enable handling of the UART found on
  458. Intel Medfield SOC and various other Intel platforms that is not
  459. covered by the more generic SERIAL_8250_PCI option.
  460. config SERIAL_8250_PERICOM
  461. tristate "Support for Pericom and Acces I/O serial ports"
  462. default SERIAL_8250
  463. depends on SERIAL_8250 && PCI
  464. help
  465. Selecting this option will enable handling of the Pericom and Acces
  466. I/O UARTs that are not covered by the more generic SERIAL_8250_PCI
  467. option.
  468. config SERIAL_8250_PXA
  469. tristate "PXA serial port support"
  470. depends on SERIAL_8250
  471. depends on ARCH_PXA || ARCH_MMP || COMPILE_TEST
  472. help
  473. If you have a machine based on an Intel XScale PXA2xx CPU you can
  474. enable its onboard serial ports by enabling this option. The option is
  475. applicable to both devicetree and legacy boards, and early console is
  476. part of its support.
  477. config SERIAL_8250_TEGRA
  478. tristate "8250 support for Tegra serial ports"
  479. default SERIAL_8250
  480. depends on SERIAL_8250
  481. depends on ARCH_TEGRA || COMPILE_TEST
  482. help
  483. Select this option if you have machine with an NVIDIA Tegra SoC and
  484. wish to enable 8250 serial driver for the Tegra serial interfaces.
  485. config SERIAL_8250_BCM7271
  486. tristate "Broadcom 8250 based serial port"
  487. depends on SERIAL_8250 && (ARCH_BRCMSTB || COMPILE_TEST)
  488. default ARCH_BRCMSTB
  489. help
  490. If you have a Broadcom STB based board and want to use the
  491. enhanced features of the Broadcom 8250 based serial port,
  492. including DMA support and high accuracy BAUD rates, say
  493. Y to this option. If unsure, say N.
  494. config SERIAL_8250_NI
  495. tristate "NI 16550 based serial port"
  496. depends on SERIAL_8250
  497. depends on X86 || COMPILE_TEST
  498. help
  499. This driver supports the integrated serial ports on National
  500. Instruments (NI) controller hardware. This is required for all NI
  501. controller models with onboard RS-485 or dual-mode RS-485/RS-232
  502. ports.
  503. To compile this driver as a module, choose M here: the module
  504. will be called 8250_ni.
  505. config SERIAL_OF_PLATFORM
  506. tristate "Devicetree based probing for 8250 ports"
  507. depends on SERIAL_8250 && OF
  508. help
  509. This option is used for all 8250 compatible serial ports that
  510. are probed through devicetree, including Open Firmware based
  511. PowerPC systems and embedded systems on architectures using the
  512. flattened device tree format.
  513. config SERIAL_8250_DWLIB
  514. bool