ftdi_sio.h 17 KB

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