xref: /openbmc/linux/drivers/usb/serial/ftdi_sio.h (revision 82e6fdd6)
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 
26 /* Commands */
27 #define FTDI_SIO_RESET			0 /* Reset the port */
28 #define FTDI_SIO_MODEM_CTRL		1 /* Set the modem control register */
29 #define FTDI_SIO_SET_FLOW_CTRL		2 /* Set flow control register */
30 #define FTDI_SIO_SET_BAUD_RATE		3 /* Set baud rate */
31 #define FTDI_SIO_SET_DATA		4 /* Set the data characteristics of
32 					     the port */
33 #define FTDI_SIO_GET_MODEM_STATUS	5 /* Retrieve current value of modem
34 					     status register */
35 #define FTDI_SIO_SET_EVENT_CHAR		6 /* Set the event character */
36 #define FTDI_SIO_SET_ERROR_CHAR		7 /* Set the error character */
37 #define FTDI_SIO_SET_LATENCY_TIMER	9 /* Set the latency timer */
38 #define FTDI_SIO_GET_LATENCY_TIMER	10 /* Get the latency timer */
39 
40 /* Interface indices for FT2232, FT2232H and FT4232H devices */
41 #define INTERFACE_A		1
42 #define INTERFACE_B		2
43 #define INTERFACE_C		3
44 #define INTERFACE_D		4
45 
46 
47 /*
48  *   BmRequestType:  1100 0000b
49  *   bRequest:       FTDI_E2_READ
50  *   wValue:         0
51  *   wIndex:         Address of word to read
52  *   wLength:        2
53  *   Data:           Will return a word of data from E2Address
54  *
55  */
56 
57 /* Port Identifier Table */
58 #define PIT_DEFAULT		0 /* SIOA */
59 #define PIT_SIOA		1 /* SIOA */
60 /* The device this driver is tested with one has only one port */
61 #define PIT_SIOB		2 /* SIOB */
62 #define PIT_PARALLEL		3 /* Parallel */
63 
64 /* FTDI_SIO_RESET */
65 #define FTDI_SIO_RESET_REQUEST FTDI_SIO_RESET
66 #define FTDI_SIO_RESET_REQUEST_TYPE 0x40
67 #define FTDI_SIO_RESET_SIO 0
68 #define FTDI_SIO_RESET_PURGE_RX 1
69 #define FTDI_SIO_RESET_PURGE_TX 2
70 
71 /*
72  * BmRequestType:  0100 0000B
73  * bRequest:       FTDI_SIO_RESET
74  * wValue:         Control Value
75  *                   0 = Reset SIO
76  *                   1 = Purge RX buffer
77  *                   2 = Purge TX buffer
78  * wIndex:         Port
79  * wLength:        0
80  * Data:           None
81  *
82  * The Reset SIO command has this effect:
83  *
84  *    Sets flow control set to 'none'
85  *    Event char = $0D
86  *    Event trigger = disabled
87  *    Purge RX buffer
88  *    Purge TX buffer
89  *    Clear DTR
90  *    Clear RTS
91  *    baud and data format not reset
92  *
93  * The Purge RX and TX buffer commands affect nothing except the buffers
94  *
95    */
96 
97 /* FTDI_SIO_SET_BAUDRATE */
98 #define FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE 0x40
99 #define FTDI_SIO_SET_BAUDRATE_REQUEST 3
100 
101 /*
102  * BmRequestType:  0100 0000B
103  * bRequest:       FTDI_SIO_SET_BAUDRATE
104  * wValue:         BaudDivisor value - see below
105  * wIndex:         Port
106  * wLength:        0
107  * Data:           None
108  * The BaudDivisor values are calculated as follows:
109  * - BaseClock is either 12000000 or 48000000 depending on the device.
110  *   FIXME: I wish I knew how to detect old chips to select proper base clock!
111  * - BaudDivisor is a fixed point number encoded in a funny way.
112  *   (--WRONG WAY OF THINKING--)
113  *   BaudDivisor is a fixed point number encoded with following bit weighs:
114  *   (-2)(-1)(13..0). It is a radical with a denominator of 4, so values
115  *   end with 0.0 (00...), 0.25 (10...), 0.5 (01...), and 0.75 (11...).
116  *   (--THE REALITY--)
117  *   The both-bits-set has quite different meaning from 0.75 - the chip
118  *   designers have decided it to mean 0.125 instead of 0.75.
119  *   This info looked up in FTDI application note "FT8U232 DEVICES \ Data Rates
120  *   and Flow Control Consideration for USB to RS232".
121  * - BaudDivisor = (BaseClock / 16) / BaudRate, where the (=) operation should
122  *   automagically re-encode the resulting value to take fractions into
123  *   consideration.
124  * As all values are integers, some bit twiddling is in order:
125  *   BaudDivisor = (BaseClock / 16 / BaudRate) |
126  *   (((BaseClock / 2 / BaudRate) & 4) ? 0x4000    // 0.5
127  *    : ((BaseClock / 2 / BaudRate) & 2) ? 0x8000  // 0.25
128  *    : ((BaseClock / 2 / BaudRate) & 1) ? 0xc000  // 0.125
129  *    : 0)
130  *
131  * For the FT232BM, a 17th divisor bit was introduced to encode the multiples
132  * of 0.125 missing from the FT8U232AM.  Bits 16 to 14 are coded as follows
133  * (the first four codes are the same as for the FT8U232AM, where bit 16 is
134  * always 0):
135  *   000 - add .000 to divisor
136  *   001 - add .500 to divisor
137  *   010 - add .250 to divisor
138  *   011 - add .125 to divisor
139  *   100 - add .375 to divisor
140  *   101 - add .625 to divisor
141  *   110 - add .750 to divisor
142  *   111 - add .875 to divisor
143  * Bits 15 to 0 of the 17-bit divisor are placed in the urb value.  Bit 16 is
144  * placed in bit 0 of the urb index.
145  *
146  * Note that there are a couple of special cases to support the highest baud
147  * rates.  If the calculated divisor value is 1, this needs to be replaced with
148  * 0.  Additionally for the FT232BM, if the calculated divisor value is 0x4001
149  * (1.5), this needs to be replaced with 0x0001 (1) (but this divisor value is
150  * not supported by the FT8U232AM).
151  */
152 
153 enum ftdi_chip_type {
154 	SIO = 1,
155 	FT8U232AM = 2,
156 	FT232BM = 3,
157 	FT2232C = 4,
158 	FT232RL = 5,
159 	FT2232H = 6,
160 	FT4232H = 7,
161 	FT232H  = 8,
162 	FTX     = 9,
163 };
164 
165 enum ftdi_sio_baudrate {
166 	ftdi_sio_b300 = 0,
167 	ftdi_sio_b600 = 1,
168 	ftdi_sio_b1200 = 2,
169 	ftdi_sio_b2400 = 3,
170 	ftdi_sio_b4800 = 4,
171 	ftdi_sio_b9600 = 5,
172 	ftdi_sio_b19200 = 6,
173 	ftdi_sio_b38400 = 7,
174 	ftdi_sio_b57600 = 8,
175 	ftdi_sio_b115200 = 9
176 };
177 
178 /*
179  * The ftdi_8U232AM_xxMHz_byyy constants have been removed. The encoded divisor
180  * values are calculated internally.
181  */
182 #define FTDI_SIO_SET_DATA_REQUEST	FTDI_SIO_SET_DATA
183 #define FTDI_SIO_SET_DATA_REQUEST_TYPE	0x40
184 #define FTDI_SIO_SET_DATA_PARITY_NONE	(0x0 << 8)
185 #define FTDI_SIO_SET_DATA_PARITY_ODD	(0x1 << 8)
186 #define FTDI_SIO_SET_DATA_PARITY_EVEN	(0x2 << 8)
187 #define FTDI_SIO_SET_DATA_PARITY_MARK	(0x3 << 8)
188 #define FTDI_SIO_SET_DATA_PARITY_SPACE	(0x4 << 8)
189 #define FTDI_SIO_SET_DATA_STOP_BITS_1	(0x0 << 11)
190 #define FTDI_SIO_SET_DATA_STOP_BITS_15	(0x1 << 11)
191 #define FTDI_SIO_SET_DATA_STOP_BITS_2	(0x2 << 11)
192 #define FTDI_SIO_SET_BREAK		(0x1 << 14)
193 /* FTDI_SIO_SET_DATA */
194 
195 /*
196  * BmRequestType:  0100 0000B
197  * bRequest:       FTDI_SIO_SET_DATA
198  * wValue:         Data characteristics (see below)
199  * wIndex:         Port
200  * wLength:        0
201  * Data:           No
202  *
203  * Data characteristics
204  *
205  *   B0..7   Number of data bits
206  *   B8..10  Parity
207  *           0 = None
208  *           1 = Odd
209  *           2 = Even
210  *           3 = Mark
211  *           4 = Space
212  *   B11..13 Stop Bits
213  *           0 = 1
214  *           1 = 1.5
215  *           2 = 2
216  *   B14
217  *           1 = TX ON (break)
218  *           0 = TX OFF (normal state)
219  *   B15 Reserved
220  *
221  */
222 
223 
224 
225 /* FTDI_SIO_MODEM_CTRL */
226 #define FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE 0x40
227 #define FTDI_SIO_SET_MODEM_CTRL_REQUEST FTDI_SIO_MODEM_CTRL
228 
229 /*
230  * BmRequestType:   0100 0000B
231  * bRequest:        FTDI_SIO_MODEM_CTRL
232  * wValue:          ControlValue (see below)
233  * wIndex:          Port
234  * wLength:         0
235  * Data:            None
236  *
237  * NOTE: If the device is in RTS/CTS flow control, the RTS set by this
238  * command will be IGNORED without an error being returned
239  * Also - you can not set DTR and RTS with one control message
240  */
241 
242 #define FTDI_SIO_SET_DTR_MASK 0x1
243 #define FTDI_SIO_SET_DTR_HIGH ((FTDI_SIO_SET_DTR_MASK  << 8) | 1)
244 #define FTDI_SIO_SET_DTR_LOW  ((FTDI_SIO_SET_DTR_MASK  << 8) | 0)
245 #define FTDI_SIO_SET_RTS_MASK 0x2
246 #define FTDI_SIO_SET_RTS_HIGH ((FTDI_SIO_SET_RTS_MASK << 8) | 2)
247 #define FTDI_SIO_SET_RTS_LOW  ((FTDI_SIO_SET_RTS_MASK << 8) | 0)
248 
249 /*
250  * ControlValue
251  * B0    DTR state
252  *          0 = reset
253  *          1 = set
254  * B1    RTS state
255  *          0 = reset
256  *          1 = set
257  * B2..7 Reserved
258  * B8    DTR state enable
259  *          0 = ignore
260  *          1 = use DTR state
261  * B9    RTS state enable
262  *          0 = ignore
263  *          1 = use RTS state
264  * B10..15 Reserved
265  */
266 
267 /* FTDI_SIO_SET_FLOW_CTRL */
268 #define FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE 0x40
269 #define FTDI_SIO_SET_FLOW_CTRL_REQUEST FTDI_SIO_SET_FLOW_CTRL
270 #define FTDI_SIO_DISABLE_FLOW_CTRL 0x0
271 #define FTDI_SIO_RTS_CTS_HS (0x1 << 8)
272 #define FTDI_SIO_DTR_DSR_HS (0x2 << 8)
273 #define FTDI_SIO_XON_XOFF_HS (0x4 << 8)
274 /*
275  *   BmRequestType:  0100 0000b
276  *   bRequest:       FTDI_SIO_SET_FLOW_CTRL
277  *   wValue:         Xoff/Xon
278  *   wIndex:         Protocol/Port - hIndex is protocol / lIndex is port
279  *   wLength:        0
280  *   Data:           None
281  *
282  * hIndex protocol is:
283  *   B0 Output handshaking using RTS/CTS
284  *       0 = disabled
285  *       1 = enabled
286  *   B1 Output handshaking using DTR/DSR
287  *       0 = disabled
288  *       1 = enabled
289  *   B2 Xon/Xoff handshaking
290  *       0 = disabled
291  *       1 = enabled
292  *
293  * A value of zero in the hIndex field disables handshaking
294  *
295  * If Xon/Xoff handshaking is specified, the hValue field should contain the
296  * XOFF character and the lValue field contains the XON character.
297  */
298 
299 /*
300  * FTDI_SIO_GET_LATENCY_TIMER
301  *
302  * Set the timeout interval. The FTDI collects data from the slave
303  * device, transmitting it to the host when either A) 62 bytes are
304  * received, or B) the timeout interval has elapsed and the buffer
305  * contains at least 1 byte.  Setting this value to a small number
306  * can dramatically improve performance for applications which send
307  * small packets, since the default value is 16ms.
308  */
309 #define  FTDI_SIO_GET_LATENCY_TIMER_REQUEST FTDI_SIO_GET_LATENCY_TIMER
310 #define  FTDI_SIO_GET_LATENCY_TIMER_REQUEST_TYPE 0xC0
311 
312 /*
313  *  BmRequestType:   1100 0000b
314  *  bRequest:        FTDI_SIO_GET_LATENCY_TIMER
315  *  wValue:          0
316  *  wIndex:          Port
317  *  wLength:         0
318  *  Data:            latency (on return)
319  */
320 
321 /*
322  * FTDI_SIO_SET_LATENCY_TIMER
323  *
324  * Set the timeout interval. The FTDI collects data from the slave
325  * device, transmitting it to the host when either A) 62 bytes are
326  * received, or B) the timeout interval has elapsed and the buffer
327  * contains at least 1 byte.  Setting this value to a small number
328  * can dramatically improve performance for applications which send
329  * small packets, since the default value is 16ms.
330  */
331 #define  FTDI_SIO_SET_LATENCY_TIMER_REQUEST FTDI_SIO_SET_LATENCY_TIMER
332 #define  FTDI_SIO_SET_LATENCY_TIMER_REQUEST_TYPE 0x40
333 
334 /*
335  *  BmRequestType:   0100 0000b
336  *  bRequest:        FTDI_SIO_SET_LATENCY_TIMER
337  *  wValue:          Latency (milliseconds)
338  *  wIndex:          Port
339  *  wLength:         0
340  *  Data:            None
341  *
342  * wValue:
343  *   B0..7   Latency timer
344  *   B8..15  0
345  *
346  */
347 
348 /*
349  * FTDI_SIO_SET_EVENT_CHAR
350  *
351  * Set the special event character for the specified communications port.
352  * If the device sees this character it will immediately return the
353  * data read so far - rather than wait 40ms or until 62 bytes are read
354  * which is what normally happens.
355  */
356 
357 
358 #define  FTDI_SIO_SET_EVENT_CHAR_REQUEST FTDI_SIO_SET_EVENT_CHAR
359 #define  FTDI_SIO_SET_EVENT_CHAR_REQUEST_TYPE 0x40
360 
361 
362 /*
363  *  BmRequestType:   0100 0000b
364  *  bRequest:        FTDI_SIO_SET_EVENT_CHAR
365  *  wValue:          EventChar
366  *  wIndex:          Port
367  *  wLength:         0
368  *  Data:            None
369  *
370  * wValue:
371  *   B0..7   Event Character
372  *   B8      Event Character Processing
373  *             0 = disabled
374  *             1 = enabled
375  *   B9..15  Reserved
376  *
377  */
378 
379 /* FTDI_SIO_SET_ERROR_CHAR */
380 
381 /*
382  * Set the parity error replacement character for the specified communications
383  * port
384  */
385 
386 /*
387  *  BmRequestType:  0100 0000b
388  *  bRequest:       FTDI_SIO_SET_EVENT_CHAR
389  *  wValue:         Error Char
390  *  wIndex:         Port
391  *  wLength:        0
392  *  Data:           None
393  *
394  *Error Char
395  *  B0..7  Error Character
396  *  B8     Error Character Processing
397  *           0 = disabled
398  *           1 = enabled
399  *  B9..15 Reserved
400  *
401  */
402 
403 /* FTDI_SIO_GET_MODEM_STATUS */
404 /* Retrieve the current value of the modem status register */
405 
406 #define FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE 0xc0
407 #define FTDI_SIO_GET_MODEM_STATUS_REQUEST FTDI_SIO_GET_MODEM_STATUS
408 #define FTDI_SIO_CTS_MASK 0x10
409 #define FTDI_SIO_DSR_MASK 0x20
410 #define FTDI_SIO_RI_MASK  0x40
411 #define FTDI_SIO_RLSD_MASK 0x80
412 /*
413  *   BmRequestType:   1100 0000b
414  *   bRequest:        FTDI_SIO_GET_MODEM_STATUS
415  *   wValue:          zero
416  *   wIndex:          Port
417  *   wLength:         1
418  *   Data:            Status
419  *
420  * One byte of data is returned
421  * B0..3 0
422  * B4    CTS
423  *         0 = inactive
424  *         1 = active
425  * B5    DSR
426  *         0 = inactive
427  *         1 = active
428  * B6    Ring Indicator (RI)
429  *         0 = inactive
430  *         1 = active
431  * B7    Receive Line Signal Detect (RLSD)
432  *         0 = inactive
433  *         1 = active
434  */
435 
436 
437 
438 /* Descriptors returned by the device
439  *
440  *  Device Descriptor
441  *
442  * Offset	Field		Size	Value	Description
443  * 0	bLength		1	0x12	Size of descriptor in bytes
444  * 1	bDescriptorType	1	0x01	DEVICE Descriptor Type
445  * 2	bcdUSB		2	0x0110	USB Spec Release Number
446  * 4	bDeviceClass	1	0x00	Class Code
447  * 5	bDeviceSubClass	1	0x00	SubClass Code
448  * 6	bDeviceProtocol	1	0x00	Protocol Code
449  * 7	bMaxPacketSize0 1	0x08	Maximum packet size for endpoint 0
450  * 8	idVendor	2	0x0403	Vendor ID
451  * 10	idProduct	2	0x8372	Product ID (FTDI_SIO_PID)
452  * 12	bcdDevice	2	0x0001	Device release number
453  * 14	iManufacturer	1	0x01	Index of man. string desc
454  * 15	iProduct	1	0x02	Index of prod string desc
455  * 16	iSerialNumber	1	0x02	Index of serial nmr string desc
456  * 17	bNumConfigurations 1    0x01	Number of possible configurations
457  *
458  * Configuration Descriptor
459  *
460  * Offset	Field			Size	Value
461  * 0	bLength			1	0x09	Size of descriptor in bytes
462  * 1	bDescriptorType		1	0x02	CONFIGURATION Descriptor Type
463  * 2	wTotalLength		2	0x0020	Total length of data
464  * 4	bNumInterfaces		1	0x01	Number of interfaces supported
465  * 5	bConfigurationValue	1	0x01	Argument for SetCOnfiguration() req
466  * 6	iConfiguration		1	0x02	Index of config string descriptor
467  * 7	bmAttributes		1	0x20	Config characteristics Remote Wakeup
468  * 8	MaxPower		1	0x1E	Max power consumption
469  *
470  * Interface Descriptor
471  *
472  * Offset	Field			Size	Value
473  * 0	bLength			1	0x09	Size of descriptor in bytes
474  * 1	bDescriptorType		1	0x04	INTERFACE Descriptor Type
475  * 2	bInterfaceNumber	1	0x00	Number of interface
476  * 3	bAlternateSetting	1	0x00	Value used to select alternate
477  * 4	bNumEndpoints		1	0x02	Number of endpoints
478  * 5	bInterfaceClass		1	0xFF	Class Code
479  * 6	bInterfaceSubClass	1	0xFF	Subclass Code
480  * 7	bInterfaceProtocol	1	0xFF	Protocol Code
481  * 8	iInterface		1	0x02	Index of interface string description
482  *
483  * IN Endpoint Descriptor
484  *
485  * Offset	Field			Size	Value
486  * 0	bLength			1	0x07	Size of descriptor in bytes
487  * 1	bDescriptorType		1	0x05	ENDPOINT descriptor type
488  * 2	bEndpointAddress	1	0x82	Address of endpoint
489  * 3	bmAttributes		1	0x02	Endpoint attributes - Bulk
490  * 4	bNumEndpoints		2	0x0040	maximum packet size
491  * 5	bInterval		1	0x00	Interval for polling endpoint
492  *
493  * OUT Endpoint Descriptor
494  *
495  * Offset	Field			Size	Value
496  * 0	bLength			1	0x07	Size of descriptor in bytes
497  * 1	bDescriptorType		1	0x05	ENDPOINT descriptor type
498  * 2	bEndpointAddress	1	0x02	Address of endpoint
499  * 3	bmAttributes		1	0x02	Endpoint attributes - Bulk
500  * 4	bNumEndpoints		2	0x0040	maximum packet size
501  * 5	bInterval		1	0x00	Interval for polling endpoint
502  *
503  * DATA FORMAT
504  *
505  * IN Endpoint
506  *
507  * The device reserves the first two bytes of data on this endpoint to contain
508  * the current values of the modem and line status registers. In the absence of
509  * data, the device generates a message consisting of these two status bytes
510  * every 40 ms
511  *
512  * Byte 0: Modem Status
513  *
514  * Offset	Description
515  * B0	Reserved - must be 1
516  * B1	Reserved - must be 0
517  * B2	Reserved - must be 0
518  * B3	Reserved - must be 0
519  * B4	Clear to Send (CTS)
520  * B5	Data Set Ready (DSR)
521  * B6	Ring Indicator (RI)
522  * B7	Receive Line Signal Detect (RLSD)
523  *
524  * Byte 1: Line Status
525  *
526  * Offset	Description
527  * B0	Data Ready (DR)
528  * B1	Overrun Error (OE)
529  * B2	Parity Error (PE)
530  * B3	Framing Error (FE)
531  * B4	Break Interrupt (BI)
532  * B5	Transmitter Holding Register (THRE)
533  * B6	Transmitter Empty (TEMT)
534  * B7	Error in RCVR FIFO
535  *
536  */
537 #define FTDI_RS0_CTS	(1 << 4)
538 #define FTDI_RS0_DSR	(1 << 5)
539 #define FTDI_RS0_RI	(1 << 6)
540 #define FTDI_RS0_RLSD	(1 << 7)
541 
542 #define FTDI_RS_DR	1
543 #define FTDI_RS_OE	(1<<1)
544 #define FTDI_RS_PE	(1<<2)
545 #define FTDI_RS_FE	(1<<3)
546 #define FTDI_RS_BI	(1<<4)
547 #define FTDI_RS_THRE	(1<<5)
548 #define FTDI_RS_TEMT	(1<<6)
549 #define FTDI_RS_FIFO	(1<<7)
550 
551 /*
552  * OUT Endpoint
553  *
554  * This device reserves the first bytes of data on this endpoint contain the
555  * length and port identifier of the message. For the FTDI USB Serial converter
556  * the port identifier is always 1.
557  *
558  * Byte 0: Line Status
559  *
560  * Offset	Description
561  * B0	Reserved - must be 1
562  * B1	Reserved - must be 0
563  * B2..7	Length of message - (not including Byte 0)
564  *
565  */
566