ftdi_sio.h 17 KB

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  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. /*
  3. * Driver definitions for the FTDI USB Single Port Serial Converter -
  4. * known as FTDI_SIO (Serial Input/Output application of the chipset)
  5. *
  6. * For USB vendor/product IDs (VID/PID), please see ftdi_sio_ids.h
  7. *
  8. *
  9. * The example I have is known as the USC-1000 which is available from
  10. * http://www.dse.co.nz - cat no XH4214 It looks similar to this:
  11. * http://www.dansdata.com/usbser.htm but I can't be sure There are other
  12. * USC-1000s which don't look like my device though so beware!
  13. *
  14. * The device is based on the FTDI FT8U100AX chip. It has a DB25 on one side,
  15. * USB on the other.
  16. *
  17. * Thanx to FTDI (http://www.ftdichip.com) for so kindly providing details
  18. * of the protocol required to talk to the device and ongoing assistence
  19. * during development.
  20. *
  21. * Bill Ryder - bryder@sgi.com formerly of Silicon Graphics, Inc.- wrote the
  22. * FTDI_SIO implementation.
  23. *
  24. */
  25. /* Commands */
  26. #define FTDI_SIO_RESET 0 /* Reset the port */
  27. #define FTDI_SIO_MODEM_CTRL 1 /* Set the modem control register */
  28. #define FTDI_SIO_SET_FLOW_CTRL 2 /* Set flow control register */
  29. #define FTDI_SIO_SET_BAUD_RATE 3 /* Set baud rate */
  30. #define FTDI_SIO_SET_DATA 4 /* Set the data characteristics of
  31. the port */
  32. #define FTDI_SIO_GET_MODEM_STATUS 5 /* Retrieve current value of modem
  33. status register */
  34. #define FTDI_SIO_SET_EVENT_CHAR 6 /* Set the event character */
  35. #define FTDI_SIO_SET_ERROR_CHAR 7 /* Set the error character */
  36. #define FTDI_SIO_SET_LATENCY_TIMER 9 /* Set the latency timer */
  37. #define FTDI_SIO_GET_LATENCY_TIMER 10 /* Get the latency timer */
  38. /* Interface indices for FT2232, FT2232H and FT4232H devices */
  39. #define INTERFACE_A 1
  40. #define INTERFACE_B 2
  41. #define INTERFACE_C 3
  42. #define INTERFACE_D 4
  43. /*
  44. * BmRequestType: 1100 0000b
  45. * bRequest: FTDI_E2_READ
  46. * wValue: 0
  47. * wIndex: Address of word to read
  48. * wLength: 2
  49. * Data: Will return a word of data from E2Address
  50. *
  51. */
  52. /* Port Identifier Table */
  53. #define PIT_DEFAULT 0 /* SIOA */
  54. #define PIT_SIOA 1 /* SIOA */
  55. /* The device this driver is tested with one has only one port */
  56. #define PIT_SIOB 2 /* SIOB */
  57. #define PIT_PARALLEL 3 /* Parallel */
  58. /* FTDI_SIO_RESET */
  59. #define FTDI_SIO_RESET_REQUEST FTDI_SIO_RESET
  60. #define FTDI_SIO_RESET_REQUEST_TYPE 0x40
  61. #define FTDI_SIO_RESET_SIO 0
  62. #define FTDI_SIO_RESET_PURGE_RX 1
  63. #define FTDI_SIO_RESET_PURGE_TX 2
  64. /*
  65. * BmRequestType: 0100 0000B
  66. * bRequest: FTDI_SIO_RESET
  67. * wValue: Control Value
  68. * 0 = Reset SIO
  69. * 1 = Purge RX buffer
  70. * 2 = Purge TX buffer
  71. * wIndex: Port
  72. * wLength: 0
  73. * Data: None
  74. *
  75. * The Reset SIO command has this effect:
  76. *
  77. * Sets flow control set to 'none'
  78. * Event char = $0D
  79. * Event trigger = disabled
  80. * Purge RX buffer
  81. * Purge TX buffer
  82. * Clear DTR
  83. * Clear RTS
  84. * baud and data format not reset
  85. *
  86. * The Purge RX and TX buffer commands affect nothing except the buffers
  87. *
  88. */
  89. /* FTDI_SIO_SET_BAUDRATE */
  90. #define FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE 0x40
  91. #define FTDI_SIO_SET_BAUDRATE_REQUEST 3
  92. /*
  93. * BmRequestType: 0100 0000B
  94. * bRequest: FTDI_SIO_SET_BAUDRATE
  95. * wValue: BaudDivisor value - see below
  96. * wIndex: Port
  97. * wLength: 0
  98. * Data: None
  99. * The BaudDivisor values are calculated as follows:
  100. * - BaseClock is either 12000000 or 48000000 depending on the device.
  101. * FIXME: I wish I knew how to detect old chips to select proper base clock!
  102. * - BaudDivisor is a fixed point number encoded in a funny way.
  103. * (--WRONG WAY OF THINKING--)
  104. * BaudDivisor is a fixed point number encoded with following bit weighs:
  105. * (-2)(-1)(13..0). It is a radical with a denominator of 4, so values
  106. * end with 0.0 (00...), 0.25 (10...), 0.5 (01...), and 0.75 (11...).
  107. * (--THE REALITY--)
  108. * The both-bits-set has quite different meaning from 0.75 - the chip
  109. * designers have decided it to mean 0.125 instead of 0.75.
  110. * This info looked up in FTDI application note "FT8U232 DEVICES \ Data Rates
  111. * and Flow Control Consideration for USB to RS232".
  112. * - BaudDivisor = (BaseClock / 16) / BaudRate, where the (=) operation should
  113. * automagically re-encode the resulting value to take fractions into
  114. * consideration.
  115. * As all values are integers, some bit twiddling is in order:
  116. * BaudDivisor = (BaseClock / 16 / BaudRate) |
  117. * (((BaseClock / 2 / BaudRate) & 4) ? 0x4000 // 0.5
  118. * : ((BaseClock / 2 / BaudRate) & 2) ? 0x8000 // 0.25
  119. * : ((BaseClock / 2 / BaudRate) & 1) ? 0xc000 // 0.125
  120. * : 0)
  121. *
  122. * For the FT232BM, a 17th divisor bit was introduced to encode the multiples
  123. * of 0.125 missing from the FT8U232AM. Bits 16 to 14 are coded as follows
  124. * (the first four codes are the same as for the FT8U232AM, where bit 16 is
  125. * always 0):
  126. * 000 - add .000 to divisor
  127. * 001 - add .500 to divisor
  128. * 010 - add .250 to divisor
  129. * 011 - add .125 to divisor
  130. * 100 - add .375 to divisor
  131. * 101 - add .625 to divisor
  132. * 110 - add .750 to divisor
  133. * 111 - add .875 to divisor
  134. * Bits 15 to 0 of the 17-bit divisor are placed in the urb value. Bit 16 is
  135. * placed in bit 0 of the urb index.
  136. *
  137. * Note that there are a couple of special cases to support the highest baud
  138. * rates. If the calculated divisor value is 1, this needs to be replaced with
  139. * 0. Additionally for the FT232BM, if the calculated divisor value is 0x4001
  140. * (1.5), this needs to be replaced with 0x0001 (1) (but this divisor value is
  141. * not supported by the FT8U232AM).
  142. */
  143. enum ftdi_chip_type {
  144. SIO = 1,
  145. FT8U232AM = 2,
  146. FT232BM = 3,
  147. FT2232C = 4,
  148. FT232RL = 5,
  149. FT2232H = 6,
  150. FT4232H = 7,
  151. FT232H = 8,
  152. FTX = 9,
  153. };
  154. enum ftdi_sio_baudrate {
  155. ftdi_sio_b300 = 0,
  156. ftdi_sio_b600 = 1,
  157. ftdi_sio_b1200 = 2,
  158. ftdi_sio_b2400 = 3,
  159. ftdi_sio_b4800 = 4,
  160. ftdi_sio_b9600 = 5,
  161. ftdi_sio_b19200 = 6,
  162. ftdi_sio_b38400 = 7,
  163. ftdi_sio_b57600 = 8,
  164. ftdi_sio_b115200 = 9
  165. };
  166. /*
  167. * The ftdi_8U232AM_xxMHz_byyy constants have been removed. The encoded divisor
  168. * values are calculated internally.
  169. */
  170. #define FTDI_SIO_SET_DATA_REQUEST FTDI_SIO_SET_DATA
  171. #define FTDI_SIO_SET_DATA_REQUEST_TYPE 0x40
  172. #define FTDI_SIO_SET_DATA_PARITY_NONE (0x0 << 8)
  173. #define FTDI_SIO_SET_DATA_PARITY_ODD (0x1 << 8)
  174. #define FTDI_SIO_SET_DATA_PARITY_EVEN (0x2 << 8)
  175. #define FTDI_SIO_SET_DATA_PARITY_MARK (0x3 << 8)
  176. #define FTDI_SIO_SET_DATA_PARITY_SPACE (0x4 << 8)
  177. #define FTDI_SIO_SET_DATA_STOP_BITS_1 (0x0 << 11)
  178. #define FTDI_SIO_SET_DATA_STOP_BITS_15 (0x1 << 11)
  179. #define FTDI_SIO_SET_DATA_STOP_BITS_2 (0x2 << 11)
  180. #define FTDI_SIO_SET_BREAK (0x1 << 14)
  181. /* FTDI_SIO_SET_DATA */
  182. /*
  183. * BmRequestType: 0100 0000B
  184. * bRequest: FTDI_SIO_SET_DATA
  185. * wValue: Data characteristics (see below)
  186. * wIndex: Port
  187. * wLength: 0
  188. * Data: No
  189. *
  190. * Data characteristics
  191. *
  192. * B0..7 Number of data bits
  193. * B8..10 Parity
  194. * 0 = None
  195. * 1 = Odd
  196. * 2 = Even
  197. * 3 = Mark
  198. * 4 = Space
  199. * B11..13 Stop Bits
  200. * 0 = 1
  201. * 1 = 1.5
  202. * 2 = 2
  203. * B14
  204. * 1 = TX ON (break)
  205. * 0 = TX OFF (normal state)
  206. * B15 Reserved
  207. *
  208. */
  209. /* FTDI_SIO_MODEM_CTRL */
  210. #define FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE 0x40
  211. #define FTDI_SIO_SET_MODEM_CTRL_REQUEST FTDI_SIO_MODEM_CTRL
  212. /*
  213. * BmRequestType: 0100 0000B
  214. * bRequest: FTDI_SIO_MODEM_CTRL
  215. * wValue: ControlValue (see below)
  216. * wIndex: Port
  217. * wLength: 0
  218. * Data: None
  219. *
  220. * NOTE: If the device is in RTS/CTS flow control, the RTS set by this
  221. * command will be IGNORED without an error being returned
  222. * Also - you can not set DTR and RTS with one control message
  223. */
  224. #define FTDI_SIO_SET_DTR_MASK 0x1
  225. #define FTDI_SIO_SET_DTR_HIGH ((FTDI_SIO_SET_DTR_MASK << 8) | 1)
  226. #define FTDI_SIO_SET_DTR_LOW ((FTDI_SIO_SET_DTR_MASK << 8) | 0)
  227. #define FTDI_SIO_SET_RTS_MASK 0x2
  228. #define FTDI_SIO_SET_RTS_HIGH ((FTDI_SIO_SET_RTS_MASK << 8) | 2)
  229. #define FTDI_SIO_SET_RTS_LOW ((FTDI_SIO_SET_RTS_MASK << 8) | 0)
  230. /*
  231. * ControlValue
  232. * B0 DTR state
  233. * 0 = reset
  234. * 1 = set
  235. * B1 RTS state
  236. * 0 = reset
  237. * 1 = set
  238. * B2..7 Reserved
  239. * B8 DTR state enable
  240. * 0 = ignore
  241. * 1 = use DTR state
  242. * B9 RTS state enable
  243. * 0 = ignore
  244. * 1 = use RTS state
  245. * B10..15 Reserved
  246. */
  247. /* FTDI_SIO_SET_FLOW_CTRL */
  248. #define FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE 0x40
  249. #define FTDI_SIO_SET_FLOW_CTRL_REQUEST FTDI_SIO_SET_FLOW_CTRL
  250. #define FTDI_SIO_DISABLE_FLOW_CTRL 0x0
  251. #define FTDI_SIO_RTS_CTS_HS (0x1 << 8)
  252. #define FTDI_SIO_DTR_DSR_HS (0x2 << 8)
  253. #define FTDI_SIO_XON_XOFF_HS (0x4 << 8)
  254. /*
  255. * BmRequestType: 0100 0000b
  256. * bRequest: FTDI_SIO_SET_FLOW_CTRL
  257. * wValue: Xoff/Xon
  258. * wIndex: Protocol/Port - hIndex is protocol / lIndex is port
  259. * wLength: 0
  260. * Data: None
  261. *
  262. * hIndex protocol is:
  263. * B0 Output handshaking using RTS/CTS
  264. * 0 = disabled
  265. * 1 = enabled
  266. * B1 Output handshaking using DTR/DSR
  267. * 0 = disabled
  268. * 1 = enabled
  269. * B2 Xon/Xoff handshaking
  270. * 0 = disabled
  271. * 1 = enabled
  272. *
  273. * A value of zero in the hIndex field disables handshaking
  274. *
  275. * If Xon/Xoff handshaking is specified, the hValue field should contain the
  276. * XOFF character and the lValue field contains the XON character.
  277. */
  278. /*
  279. * FTDI_SIO_GET_LATENCY_TIMER
  280. *
  281. * Set the timeout interval. The FTDI collects data from the slave
  282. * device, transmitting it to the host when either A) 62 bytes are
  283. * received, or B) the timeout interval has elapsed and the buffer
  284. * contains at least 1 byte. Setting this value to a small number
  285. * can dramatically improve performance for applications which send
  286. * small packets, since the default value is 16ms.
  287. */
  288. #define FTDI_SIO_GET_LATENCY_TIMER_REQUEST FTDI_SIO_GET_LATENCY_TIMER
  289. #define FTDI_SIO_GET_LATENCY_TIMER_REQUEST_TYPE 0xC0
  290. /*
  291. * BmRequestType: 1100 0000b
  292. * bRequest: FTDI_SIO_GET_LATENCY_TIMER
  293. * wValue: 0
  294. * wIndex: Port
  295. * wLength: 0
  296. * Data: latency (on return)
  297. */
  298. /*
  299. * FTDI_SIO_SET_LATENCY_TIMER
  300. *
  301. * Set the timeout interval. The FTDI collects data from the slave
  302. * device, transmitting it to the host when either A) 62 bytes are
  303. * received, or B) the timeout interval has elapsed and the buffer
  304. * contains at least 1 byte. Setting this value to a small number
  305. * can dramatically improve performance for applications which send
  306. * small packets, since the default value is 16ms.
  307. */
  308. #define FTDI_SIO_SET_LATENCY_TIMER_REQUEST FTDI_SIO_SET_LATENCY_TIMER
  309. #define FTDI_SIO_SET_LATENCY_TIMER_REQUEST_TYPE 0x40
  310. /*
  311. * BmRequestType: 0100 0000b
  312. * bRequest: FTDI_SIO_SET_LATENCY_TIMER
  313. * wValue: Latency (milliseconds)
  314. * wIndex: Port
  315. * wLength: 0
  316. * Data: None
  317. *
  318. * wValue:
  319. * B0..7 Latency timer
  320. * B8..15 0
  321. *
  322. */
  323. /*
  324. * FTDI_SIO_SET_EVENT_CHAR
  325. *
  326. * Set the special event character for the specified communications port.
  327. * If the device sees this character it will immediately return the
  328. * data read so far - rather than wait 40ms or until 62 bytes are read
  329. * which is what normally happens.
  330. */
  331. #define FTDI_SIO_SET_EVENT_CHAR_REQUEST FTDI_SIO_SET_EVENT_CHAR
  332. #define FTDI_SIO_SET_EVENT_CHAR_REQUEST_TYPE 0x40
  333. /*
  334. * BmRequestType: 0100 0000b
  335. * bRequest: FTDI_SIO_SET_EVENT_CHAR
  336. * wValue: EventChar
  337. * wIndex: Port
  338. * wLength: 0
  339. * Data: None
  340. *
  341. * wValue:
  342. * B0..7 Event Character
  343. * B8 Event Character Processing
  344. * 0 = disabled
  345. * 1 = enabled
  346. * B9..15 Reserved
  347. *
  348. */
  349. /* FTDI_SIO_SET_ERROR_CHAR */
  350. /*
  351. * Set the parity error replacement character for the specified communications
  352. * port
  353. */
  354. /*
  355. * BmRequestType: 0100 0000b
  356. * bRequest: FTDI_SIO_SET_EVENT_CHAR
  357. * wValue: Error Char
  358. * wIndex: Port
  359. * wLength: 0
  360. * Data: None
  361. *
  362. *Error Char
  363. * B0..7 Error Character
  364. * B8 Error Character Processing
  365. * 0 = disabled
  366. * 1 = enabled
  367. * B9..15 Reserved
  368. *
  369. */
  370. /* FTDI_SIO_GET_MODEM_STATUS */
  371. /* Retrieve the current value of the modem status register */
  372. #define FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE 0xc0
  373. #define FTDI_SIO_GET_MODEM_STATUS_REQUEST FTDI_SIO_GET_MODEM_STATUS
  374. #define FTDI_SIO_CTS_MASK 0x10
  375. #define FTDI_SIO_DSR_MASK 0x20
  376. #define FTDI_SIO_RI_MASK 0x40
  377. #define FTDI_SIO_RLSD_MASK 0x80
  378. /*
  379. * BmRequestType: 1100 0000b
  380. * bRequest: FTDI_SIO_GET_MODEM_STATUS
  381. * wValue: zero
  382. * wIndex: Port
  383. * wLength: 1
  384. * Data: Status
  385. *
  386. * One byte of data is returned
  387. * B0..3 0
  388. * B4 CTS
  389. * 0 = inactive
  390. * 1 = active
  391. * B5 DSR
  392. * 0 = inactive
  393. * 1 = active
  394. * B6 Ring Indicator (RI)
  395. * 0 = inactive
  396. * 1 = active
  397. * B7 Receive Line Signal Detect (RLSD)
  398. * 0 = inactive
  399. * 1 = active
  400. */
  401. /* Descriptors returned by the device
  402. *
  403. * Device Descriptor
  404. *
  405. * Offset Field Size Value Description
  406. * 0 bLength 1 0x12 Size of descriptor in bytes
  407. * 1 bDescriptorType 1 0x01 DEVICE Descriptor Type
  408. * 2 bcdUSB 2 0x0110 USB Spec Release Number
  409. * 4 bDeviceClass 1 0x00 Class Code
  410. * 5 bDeviceSubClass 1 0x00 SubClass Code
  411. * 6 bDeviceProtocol 1 0x00 Protocol Code
  412. * 7 bMaxPacketSize0 1 0x08 Maximum packet size for endpoint 0
  413. * 8 idVendor 2 0x0403 Vendor ID
  414. * 10 idProduct 2 0x8372 Product ID (FTDI_SIO_PID)
  415. * 12 bcdDevice 2 0x0001 Device release number
  416. * 14 iManufacturer 1 0x01 Index of man. string desc
  417. * 15 iProduct 1 0x02 Index of prod string desc
  418. * 16 iSerialNumber 1 0x02 Index of serial nmr string desc
  419. * 17 bNumConfigurations 1 0x01 Number of possible configurations
  420. *
  421. * Configuration Descriptor
  422. *
  423. * Offset Field Size Value
  424. * 0 bLength 1 0x09 Size of descriptor in bytes
  425. * 1 bDescriptorType 1 0x02 CONFIGURATION Descriptor Type
  426. * 2 wTotalLength 2 0x0020 Total length of data
  427. * 4 bNumInterfaces 1 0x01 Number of interfaces supported
  428. * 5 bConfigurationValue 1 0x01 Argument for SetCOnfiguration() req
  429. * 6 iConfiguration 1 0x02 Index of config string descriptor
  430. * 7 bmAttributes 1 0x20 Config characteristics Remote Wakeup
  431. * 8 MaxPower 1 0x1E Max power consumption
  432. *
  433. * Interface Descriptor
  434. *
  435. * Offset Field Size Value
  436. * 0 bLength 1 0x09 Size of descriptor in bytes
  437. * 1 bDescriptorType 1 0x04 INTERFACE Descriptor Type
  438. * 2 bInterfaceNumber 1 0x00 Number of interface
  439. * 3 bAlternateSetting 1 0x00 Value used to select alternate
  440. * 4 bNumEndpoints 1 0x02 Number of endpoints
  441. * 5 bInterfaceClass 1 0xFF Class Code
  442. * 6 bInterfaceSubClass 1 0xFF Subclass Code
  443. * 7 bInterfaceProtocol 1 0xFF Protocol Code
  444. * 8 iInterface 1 0x02 Index of interface string description
  445. *
  446. * IN Endpoint Descriptor
  447. *
  448. * Offset Field Size Value
  449. * 0 bLength 1 0x07 Size of descriptor in bytes
  450. * 1 bDescriptorType 1 0x05 ENDPOINT descriptor type
  451. * 2 bEndpointAddress 1 0x82 Address of endpoint
  452. * 3 bmAttributes 1 0x02 Endpoint attributes - Bulk
  453. * 4 bNumEndpoints 2 0x0040 maximum packet size
  454. * 5 bInterval 1 0x00 Interval for polling endpoint
  455. *
  456. * OUT Endpoint Descriptor
  457. *
  458. * Offset Field Size Value
  459. * 0 bLength 1 0x07 Size of descriptor in bytes
  460. * 1 bDescriptorType 1 0x05 ENDPOINT descriptor type
  461. * 2 bEndpointAddress 1 0x02 Address of endpoint
  462. * 3 bmAttributes 1 0x02 Endpoint attributes - Bulk
  463. * 4 bNumEndpoints 2 0x0040 maximum packet size
  464. * 5 bInterval 1 0x00 Interval for polling endpoint
  465. *
  466. * DATA FORMAT
  467. *
  468. * IN Endpoint
  469. *
  470. * The device reserves the first two bytes of data on this endpoint to contain
  471. * the current values of the modem and line status registers. In the absence of
  472. * data, the device generates a message consisting of these two status bytes
  473. * every 40 ms
  474. *
  475. * Byte 0: Modem Status
  476. *
  477. * Offset Description
  478. * B0 Reserved - must be 1
  479. * B1 Reserved - must be 0
  480. * B2 Reserved - must be 0
  481. * B3 Reserved - must be 0
  482. * B4 Clear to Send (CTS)
  483. * B5 Data Set Ready (DSR)
  484. * B6 Ring Indicator (RI)
  485. * B7 Receive Line Signal Detect (RLSD)
  486. *
  487. * Byte 1: Line Status
  488. *
  489. * Offset Description
  490. * B0 Data Ready (DR)
  491. * B1 Overrun Error (OE)
  492. * B2 Parity Error (PE)
  493. * B3 Framing Error (FE)
  494. * B4 Break Interrupt (BI)
  495. * B5 Transmitter Holding Register (THRE)
  496. * B6 Transmitter Empty (TEMT)
  497. * B7 Error in RCVR FIFO
  498. *
  499. */
  500. #define FTDI_RS0_CTS (1 << 4)
  501. #define FTDI_RS0_DSR (1 << 5)
  502. #define FTDI_RS0_RI (1 << 6)
  503. #define FTDI_RS0_RLSD (1 << 7)
  504. #define FTDI_RS_DR 1
  505. #define FTDI_RS_OE (1<<1)
  506. #define FTDI_RS_PE (1<<2)
  507. #define FTDI_RS_FE (1<<3)
  508. #define FTDI_RS_BI (1<<4)
  509. #define FTDI_RS_THRE (1<<5)
  510. #define FTDI_RS_TEMT (1<<6)
  511. #define FTDI_RS_FIFO (1<<7)
  512. /*
  513. * OUT Endpoint
  514. *
  515. * This device reserves the first bytes of data on this endpoint contain the
  516. * length and port identifier of the message. For the FTDI USB Serial converter
  517. * the port identifier is always 1.
  518. *
  519. * Byte 0: Line Status
  520. *
  521. * Offset Description
  522. * B0 Reserved - must be 1
  523. * B1 Reserved - must be 0
  524. * B2..7 Length of message - (not including Byte 0)
  525. *
  526. */