1 /***************************************************************************
5 copyright : (C) 2003-2008 by Intra2net AG
6 email : opensource@intra2net.com
7 ***************************************************************************/
9 /***************************************************************************
11 * This program is free software; you can redistribute it and/or modify *
12 * it under the terms of the GNU Lesser General Public License *
13 * version 2.1 as published by the Free Software Foundation; *
15 ***************************************************************************/
18 \mainpage libftdi API documentation
20 Library to talk to FTDI chips. You find the latest versions of libftdi at
21 http://www.intra2net.com/de/produkte/opensource/ftdi/
23 The library is easy to use. Have a look at this short example:
26 More examples can be found in the "examples" directory.
28 /** \addtogroup libftdi */
37 /* stuff needed for async write */
38 #include <sys/ioctl.h>
40 #include <sys/select.h>
41 #include <sys/types.h>
43 #include <linux/usbdevice_fs.h>
45 #define ftdi_error_return(code, str) do { \
46 ftdi->error_str = str; \
52 Initializes a ftdi_context.
54 \param ftdi pointer to ftdi_context
57 \retval -1: couldn't allocate read buffer
59 \remark This should be called before all functions
61 int ftdi_init(struct ftdi_context *ftdi)
66 ftdi->usb_read_timeout = 5000;
67 ftdi->usb_write_timeout = 5000;
69 ftdi->type = TYPE_BM; /* chip type */
71 ftdi->bitbang_enabled = 0;
73 ftdi->readbuffer = NULL;
74 ftdi->readbuffer_offset = 0;
75 ftdi->readbuffer_remaining = 0;
76 ftdi->writebuffer_chunksize = 4096;
82 ftdi->bitbang_mode = 1; /* 1: Normal bitbang mode, 2: SPI bitbang mode */
84 ftdi->error_str = NULL;
86 ftdi->async_usb_buffer_size=10;
87 if ((ftdi->async_usb_buffer=malloc(sizeof(struct usbdevfs_urb)*ftdi->async_usb_buffer_size)) == NULL)
88 ftdi_error_return(-1, "out of memory for async usb buffer");
90 /* initialize async usb buffer with unused-marker */
91 for (i=0; i < ftdi->async_usb_buffer_size; i++)
92 ((struct usbdevfs_urb*)ftdi->async_usb_buffer)[i].usercontext = FTDI_URB_USERCONTEXT_COOKIE;
94 ftdi->eeprom_size = FTDI_DEFAULT_EEPROM_SIZE;
96 /* All fine. Now allocate the readbuffer */
97 return ftdi_read_data_set_chunksize(ftdi, 4096);
101 Open selected channels on a chip, otherwise use first channel.
103 \param ftdi pointer to ftdi_context
104 \param interface Interface to use for FT2232C chips.
107 \retval -1: unknown interface
109 int ftdi_set_interface(struct ftdi_context *ftdi, enum ftdi_interface interface)
114 /* ftdi_usb_open_desc cares to set the right index, depending on the found chip */
118 ftdi->index = INTERFACE_B;
123 ftdi_error_return(-1, "Unknown interface");
129 Deinitializes a ftdi_context.
131 \param ftdi pointer to ftdi_context
133 void ftdi_deinit(struct ftdi_context *ftdi)
135 if (ftdi->async_usb_buffer != NULL) {
136 free(ftdi->async_usb_buffer);
137 ftdi->async_usb_buffer = NULL;
140 if (ftdi->readbuffer != NULL) {
141 free(ftdi->readbuffer);
142 ftdi->readbuffer = NULL;
147 Use an already open libusb device.
149 \param ftdi pointer to ftdi_context
150 \param usb libusb usb_dev_handle to use
152 void ftdi_set_usbdev (struct ftdi_context *ftdi, usb_dev_handle *usb)
159 Finds all ftdi devices on the usb bus. Creates a new ftdi_device_list which
160 needs to be deallocated by ftdi_list_free() after use.
162 \param ftdi pointer to ftdi_context
163 \param devlist Pointer where to store list of found devices
164 \param vendor Vendor ID to search for
165 \param product Product ID to search for
167 \retval >0: number of devices found
168 \retval -1: usb_find_busses() failed
169 \retval -2: usb_find_devices() failed
170 \retval -3: out of memory
172 int ftdi_usb_find_all(struct ftdi_context *ftdi, struct ftdi_device_list **devlist, int vendor, int product)
174 struct ftdi_device_list **curdev;
176 struct usb_device *dev;
180 if (usb_find_busses() < 0)
181 ftdi_error_return(-1, "usb_find_busses() failed");
182 if (usb_find_devices() < 0)
183 ftdi_error_return(-2, "usb_find_devices() failed");
187 for (bus = usb_busses; bus; bus = bus->next) {
188 for (dev = bus->devices; dev; dev = dev->next) {
189 if (dev->descriptor.idVendor == vendor
190 && dev->descriptor.idProduct == product)
192 *curdev = (struct ftdi_device_list*)malloc(sizeof(struct ftdi_device_list));
194 ftdi_error_return(-3, "out of memory");
196 (*curdev)->next = NULL;
197 (*curdev)->dev = dev;
199 curdev = &(*curdev)->next;
209 Frees a usb device list.
211 \param devlist USB device list created by ftdi_usb_find_all()
213 void ftdi_list_free(struct ftdi_device_list **devlist)
215 struct ftdi_device_list *curdev, *next;
217 for (curdev = *devlist; curdev != NULL;) {
227 Return device ID strings from the usb device.
229 The parameters manufacturer, description and serial may be NULL
230 or pointer to buffers to store the fetched strings.
232 \note Use this function only in combination with ftdi_usb_find_all()
233 as it closes the internal "usb_dev" after use.
235 \param ftdi pointer to ftdi_context
236 \param dev libusb usb_dev to use
237 \param manufacturer Store manufacturer string here if not NULL
238 \param mnf_len Buffer size of manufacturer string
239 \param description Store product description string here if not NULL
240 \param desc_len Buffer size of product description string
241 \param serial Store serial string here if not NULL
242 \param serial_len Buffer size of serial string
245 \retval -1: wrong arguments
246 \retval -4: unable to open device
247 \retval -7: get product manufacturer failed
248 \retval -8: get product description failed
249 \retval -9: get serial number failed
250 \retval -10: unable to close device
252 int ftdi_usb_get_strings(struct ftdi_context * ftdi, struct usb_device * dev,
253 char * manufacturer, int mnf_len, char * description, int desc_len, char * serial, int serial_len)
255 if ((ftdi==NULL) || (dev==NULL))
258 if (!(ftdi->usb_dev = usb_open(dev)))
259 ftdi_error_return(-4, usb_strerror());
261 if (manufacturer != NULL) {
262 if (usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iManufacturer, manufacturer, mnf_len) <= 0) {
263 usb_close (ftdi->usb_dev);
264 ftdi_error_return(-7, usb_strerror());
268 if (description != NULL) {
269 if (usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iProduct, description, desc_len) <= 0) {
270 usb_close (ftdi->usb_dev);
271 ftdi_error_return(-8, usb_strerror());
275 if (serial != NULL) {
276 if (usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iSerialNumber, serial, serial_len) <= 0) {
277 usb_close (ftdi->usb_dev);
278 ftdi_error_return(-9, usb_strerror());
282 if (usb_close (ftdi->usb_dev) != 0)
283 ftdi_error_return(-10, usb_strerror());
289 Opens a ftdi device given by a usb_device.
291 \param ftdi pointer to ftdi_context
292 \param dev libusb usb_dev to use
295 \retval -4: unable to open device
296 \retval -5: unable to claim device
297 \retval -6: reset failed
298 \retval -7: set baudrate failed
300 int ftdi_usb_open_dev(struct ftdi_context *ftdi, struct usb_device *dev)
302 int detach_errno = 0;
303 if (!(ftdi->usb_dev = usb_open(dev)))
304 ftdi_error_return(-4, "usb_open() failed");
306 #ifdef LIBUSB_HAS_GET_DRIVER_NP
307 // Try to detach ftdi_sio kernel module
308 // Returns ENODATA if driver is not loaded
309 if (usb_detach_kernel_driver_np(ftdi->usb_dev, ftdi->interface) != 0 && errno != ENODATA)
310 detach_errno = errno;
313 if (usb_claim_interface(ftdi->usb_dev, ftdi->interface) != 0) {
314 usb_close (ftdi->usb_dev);
315 if (detach_errno == EPERM) {
316 ftdi_error_return(-8, "inappropriate permissions on device!");
318 ftdi_error_return(-5, "unable to claim usb device. Make sure ftdi_sio is unloaded!");
322 if (ftdi_usb_reset (ftdi) != 0) {
323 usb_close (ftdi->usb_dev);
324 ftdi_error_return(-6, "ftdi_usb_reset failed");
327 if (ftdi_set_baudrate (ftdi, 9600) != 0) {
328 usb_close (ftdi->usb_dev);
329 ftdi_error_return(-7, "set baudrate failed");
332 // Try to guess chip type
333 // Bug in the BM type chips: bcdDevice is 0x200 for serial == 0
334 if (dev->descriptor.bcdDevice == 0x400 || (dev->descriptor.bcdDevice == 0x200
335 && dev->descriptor.iSerialNumber == 0))
336 ftdi->type = TYPE_BM;
337 else if (dev->descriptor.bcdDevice == 0x200)
338 ftdi->type = TYPE_AM;
339 else if (dev->descriptor.bcdDevice == 0x500) {
340 ftdi->type = TYPE_2232C;
342 ftdi->index = INTERFACE_A;
343 } else if (dev->descriptor.bcdDevice == 0x600)
346 ftdi_error_return(0, "all fine");
350 Opens the first device with a given vendor and product ids.
352 \param ftdi pointer to ftdi_context
353 \param vendor Vendor ID
354 \param product Product ID
356 \retval same as ftdi_usb_open_desc()
358 int ftdi_usb_open(struct ftdi_context *ftdi, int vendor, int product)
360 return ftdi_usb_open_desc(ftdi, vendor, product, NULL, NULL);
364 Opens the first device with a given, vendor id, product id,
365 description and serial.
367 \param ftdi pointer to ftdi_context
368 \param vendor Vendor ID
369 \param product Product ID
370 \param description Description to search for. Use NULL if not needed.
371 \param serial Serial to search for. Use NULL if not needed.
374 \retval -1: usb_find_busses() failed
375 \retval -2: usb_find_devices() failed
376 \retval -3: usb device not found
377 \retval -4: unable to open device
378 \retval -5: unable to claim device
379 \retval -6: reset failed
380 \retval -7: set baudrate failed
381 \retval -8: get product description failed
382 \retval -9: get serial number failed
383 \retval -10: unable to close device
385 int ftdi_usb_open_desc(struct ftdi_context *ftdi, int vendor, int product,
386 const char* description, const char* serial)
389 struct usb_device *dev;
394 if (usb_find_busses() < 0)
395 ftdi_error_return(-1, "usb_find_busses() failed");
396 if (usb_find_devices() < 0)
397 ftdi_error_return(-2, "usb_find_devices() failed");
399 for (bus = usb_busses; bus; bus = bus->next) {
400 for (dev = bus->devices; dev; dev = dev->next) {
401 if (dev->descriptor.idVendor == vendor
402 && dev->descriptor.idProduct == product) {
403 if (!(ftdi->usb_dev = usb_open(dev)))
404 ftdi_error_return(-4, "usb_open() failed");
406 if (description != NULL) {
407 if (usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iProduct, string, sizeof(string)) <= 0) {
408 usb_close (ftdi->usb_dev);
409 ftdi_error_return(-8, "unable to fetch product description");
411 if (strncmp(string, description, sizeof(string)) != 0) {
412 if (usb_close (ftdi->usb_dev) != 0)
413 ftdi_error_return(-10, "unable to close device");
417 if (serial != NULL) {
418 if (usb_get_string_simple(ftdi->usb_dev, dev->descriptor.iSerialNumber, string, sizeof(string)) <= 0) {
419 usb_close (ftdi->usb_dev);
420 ftdi_error_return(-9, "unable to fetch serial number");
422 if (strncmp(string, serial, sizeof(string)) != 0) {
423 if (usb_close (ftdi->usb_dev) != 0)
424 ftdi_error_return(-10, "unable to close device");
429 if (usb_close (ftdi->usb_dev) != 0)
430 ftdi_error_return(-10, "unable to close device");
432 return ftdi_usb_open_dev(ftdi, dev);
438 ftdi_error_return(-3, "device not found");
442 Resets the ftdi device.
444 \param ftdi pointer to ftdi_context
447 \retval -1: FTDI reset failed
449 int ftdi_usb_reset(struct ftdi_context *ftdi)
451 if (usb_control_msg(ftdi->usb_dev, 0x40, 0, 0, ftdi->index, NULL, 0, ftdi->usb_write_timeout) != 0)
452 ftdi_error_return(-1,"FTDI reset failed");
454 // Invalidate data in the readbuffer
455 ftdi->readbuffer_offset = 0;
456 ftdi->readbuffer_remaining = 0;
462 Clears the buffers on the chip.
464 \param ftdi pointer to ftdi_context
467 \retval -1: write buffer purge failed
468 \retval -2: read buffer purge failed
470 int ftdi_usb_purge_buffers(struct ftdi_context *ftdi)
472 if (usb_control_msg(ftdi->usb_dev, 0x40, 0, 1, ftdi->index, NULL, 0, ftdi->usb_write_timeout) != 0)
473 ftdi_error_return(-1, "FTDI purge of RX buffer failed");
475 // Invalidate data in the readbuffer
476 ftdi->readbuffer_offset = 0;
477 ftdi->readbuffer_remaining = 0;
479 if (usb_control_msg(ftdi->usb_dev, 0x40, 0, 2, ftdi->index, NULL, 0, ftdi->usb_write_timeout) != 0)
480 ftdi_error_return(-2, "FTDI purge of TX buffer failed");
486 Closes the ftdi device. Call ftdi_deinit() if you're cleaning up.
488 \param ftdi pointer to ftdi_context
491 \retval -1: usb_release failed
492 \retval -2: usb_close failed
494 int ftdi_usb_close(struct ftdi_context *ftdi)
498 /* try to release some kernel resources */
499 ftdi_async_complete(ftdi,1);
501 if (usb_release_interface(ftdi->usb_dev, ftdi->interface) != 0)
504 if (usb_close (ftdi->usb_dev) != 0)
511 ftdi_convert_baudrate returns nearest supported baud rate to that requested.
512 Function is only used internally
515 static int ftdi_convert_baudrate(int baudrate, struct ftdi_context *ftdi,
516 unsigned short *value, unsigned short *index)
518 static const char am_adjust_up[8] = {0, 0, 0, 1, 0, 3, 2, 1};
519 static const char am_adjust_dn[8] = {0, 0, 0, 1, 0, 1, 2, 3};
520 static const char frac_code[8] = {0, 3, 2, 4, 1, 5, 6, 7};
521 int divisor, best_divisor, best_baud, best_baud_diff;
522 unsigned long encoded_divisor;
530 divisor = 24000000 / baudrate;
532 if (ftdi->type == TYPE_AM) {
533 // Round down to supported fraction (AM only)
534 divisor -= am_adjust_dn[divisor & 7];
537 // Try this divisor and the one above it (because division rounds down)
541 for (i = 0; i < 2; i++) {
542 int try_divisor = divisor + i;
546 // Round up to supported divisor value
547 if (try_divisor <= 8) {
548 // Round up to minimum supported divisor
550 } else if (ftdi->type != TYPE_AM && try_divisor < 12) {
551 // BM doesn't support divisors 9 through 11 inclusive
553 } else if (divisor < 16) {
554 // AM doesn't support divisors 9 through 15 inclusive
557 if (ftdi->type == TYPE_AM) {
558 // Round up to supported fraction (AM only)
559 try_divisor += am_adjust_up[try_divisor & 7];
560 if (try_divisor > 0x1FFF8) {
561 // Round down to maximum supported divisor value (for AM)
562 try_divisor = 0x1FFF8;
565 if (try_divisor > 0x1FFFF) {
566 // Round down to maximum supported divisor value (for BM)
567 try_divisor = 0x1FFFF;
571 // Get estimated baud rate (to nearest integer)
572 baud_estimate = (24000000 + (try_divisor / 2)) / try_divisor;
573 // Get absolute difference from requested baud rate
574 if (baud_estimate < baudrate) {
575 baud_diff = baudrate - baud_estimate;
577 baud_diff = baud_estimate - baudrate;
579 if (i == 0 || baud_diff < best_baud_diff) {
580 // Closest to requested baud rate so far
581 best_divisor = try_divisor;
582 best_baud = baud_estimate;
583 best_baud_diff = baud_diff;
584 if (baud_diff == 0) {
585 // Spot on! No point trying
590 // Encode the best divisor value
591 encoded_divisor = (best_divisor >> 3) | (frac_code[best_divisor & 7] << 14);
592 // Deal with special cases for encoded value
593 if (encoded_divisor == 1) {
594 encoded_divisor = 0; // 3000000 baud
595 } else if (encoded_divisor == 0x4001) {
596 encoded_divisor = 1; // 2000000 baud (BM only)
598 // Split into "value" and "index" values
599 *value = (unsigned short)(encoded_divisor & 0xFFFF);
600 if(ftdi->type == TYPE_2232C) {
601 *index = (unsigned short)(encoded_divisor >> 8);
603 *index |= ftdi->index;
606 *index = (unsigned short)(encoded_divisor >> 16);
608 // Return the nearest baud rate
613 Sets the chip baud rate
615 \param ftdi pointer to ftdi_context
616 \param baudrate baud rate to set
619 \retval -1: invalid baudrate
620 \retval -2: setting baudrate failed
622 int ftdi_set_baudrate(struct ftdi_context *ftdi, int baudrate)
624 unsigned short value, index;
627 if (ftdi->bitbang_enabled) {
628 baudrate = baudrate*4;
631 actual_baudrate = ftdi_convert_baudrate(baudrate, ftdi, &value, &index);
632 if (actual_baudrate <= 0)
633 ftdi_error_return (-1, "Silly baudrate <= 0.");
635 // Check within tolerance (about 5%)
636 if ((actual_baudrate * 2 < baudrate /* Catch overflows */ )
637 || ((actual_baudrate < baudrate)
638 ? (actual_baudrate * 21 < baudrate * 20)
639 : (baudrate * 21 < actual_baudrate * 20)))
640 ftdi_error_return (-1, "Unsupported baudrate. Note: bitbang baudrates are automatically multiplied by 4");
642 if (usb_control_msg(ftdi->usb_dev, 0x40, 3, value, index, NULL, 0, ftdi->usb_write_timeout) != 0)
643 ftdi_error_return (-2, "Setting new baudrate failed");
645 ftdi->baudrate = baudrate;
650 Set (RS232) line characteristics by Alain Abbas
652 \param ftdi pointer to ftdi_context
653 \param bits Number of bits
654 \param sbit Number of stop bits
655 \param parity Parity mode
658 \retval -1: Setting line property failed
660 int ftdi_set_line_property(struct ftdi_context *ftdi, enum ftdi_bits_type bits,
661 enum ftdi_stopbits_type sbit, enum ftdi_parity_type parity)
663 unsigned short value = bits;
667 value |= (0x00 << 8);
670 value |= (0x01 << 8);
673 value |= (0x02 << 8);
676 value |= (0x03 << 8);
679 value |= (0x04 << 8);
685 value |= (0x00 << 11);
688 value |= (0x01 << 11);
691 value |= (0x02 << 11);
695 if (usb_control_msg(ftdi->usb_dev, 0x40, 0x04, value, ftdi->index, NULL, 0, ftdi->usb_write_timeout) != 0)
696 ftdi_error_return (-1, "Setting new line property failed");
702 Writes data in chunks (see ftdi_write_data_set_chunksize()) to the chip
704 \param ftdi pointer to ftdi_context
705 \param buf Buffer with the data
706 \param size Size of the buffer
708 \retval <0: error code from usb_bulk_write()
709 \retval >0: number of bytes written
711 int ftdi_write_data(struct ftdi_context *ftdi, unsigned char *buf, int size)
715 int total_written = 0;
717 while (offset < size) {
718 int write_size = ftdi->writebuffer_chunksize;
720 if (offset+write_size > size)
721 write_size = size-offset;
723 ret = usb_bulk_write(ftdi->usb_dev, ftdi->in_ep, buf+offset, write_size, ftdi->usb_write_timeout);
725 ftdi_error_return(ret, "usb bulk write failed");
727 total_written += ret;
728 offset += write_size;
731 return total_written;
734 /* this is strongly dependent on libusb using the same struct layout. If libusb
735 changes in some later version this may break horribly (this is for libusb 0.1.12) */
736 struct usb_dev_handle {
738 // some other stuff coming here we don't need
742 Check for pending async urbs
745 static int _usb_get_async_urbs_pending(struct ftdi_context *ftdi)
747 struct usbdevfs_urb *urb;
751 for (i=0; i < ftdi->async_usb_buffer_size; i++) {
752 urb=&((struct usbdevfs_urb *)(ftdi->async_usb_buffer))[i];
753 if (urb->usercontext != FTDI_URB_USERCONTEXT_COOKIE)
761 FIXME: Gerd, what does this function do exactly?
764 static void _usb_async_cleanup(struct ftdi_context *ftdi, int wait_for_more, int timeout_msec)
767 struct usbdevfs_urb *urb=NULL;
773 FD_SET(ftdi->usb_dev->fd, &writefds);
775 /* init timeout only once, select writes time left after call */
776 tv.tv_sec = timeout_msec / 1000;
777 tv.tv_usec = (timeout_msec % 1000) * 1000;
780 while (_usb_get_async_urbs_pending(ftdi)
781 && (ret = ioctl(ftdi->usb_dev->fd, USBDEVFS_REAPURBNDELAY, &urb)) == -1
784 if (keep_going && !wait_for_more) {
785 /* don't wait if repeating only for keep_going */
790 /* wait for timeout msec or something written ready */
791 select(ftdi->usb_dev->fd+1, NULL, &writefds, NULL, &tv);
794 if (ret == 0 && urb != NULL) {
795 /* got a free urb, mark it */
796 urb->usercontext = FTDI_URB_USERCONTEXT_COOKIE;
798 /* try to get more urbs that are ready now, but don't wait anymore */
802 /* no more urbs waiting */
805 } while (keep_going);
809 Wait until at least one async write is complete
811 \param ftdi pointer to ftdi_context
812 \param wait_for_more if != 0 wait for more than one write to complete (until write timeout)
814 void ftdi_async_complete(struct ftdi_context *ftdi, int wait_for_more)
816 _usb_async_cleanup(ftdi,wait_for_more,ftdi->usb_write_timeout);
820 Stupid libusb does not offer async writes nor does it allow
821 access to its fd - so we need some hacks here.
824 static int _usb_bulk_write_async(struct ftdi_context *ftdi, int ep, char *bytes, int size)
826 struct usbdevfs_urb *urb;
827 int bytesdone = 0, requested;
832 /* find a free urb buffer we can use */
834 for (cleanup_count=0; urb==NULL && cleanup_count <= 1; cleanup_count++)
836 if (i==ftdi->async_usb_buffer_size) {
837 /* wait until some buffers are free */
838 _usb_async_cleanup(ftdi,0,ftdi->usb_write_timeout);
841 for (i=0; i < ftdi->async_usb_buffer_size; i++) {
842 urb=&((struct usbdevfs_urb *)(ftdi->async_usb_buffer))[i];
843 if (urb->usercontext == FTDI_URB_USERCONTEXT_COOKIE)
844 break; /* found a free urb position */
849 /* no free urb position found */
853 requested = size - bytesdone;
854 if (requested > 4096)
857 memset(urb,0,sizeof(urb));
859 urb->type = USBDEVFS_URB_TYPE_BULK;
862 urb->buffer = bytes + bytesdone;
863 urb->buffer_length = requested;
865 urb->actual_length = 0;
866 urb->number_of_packets = 0;
867 urb->usercontext = 0;
870 ret = ioctl(ftdi->usb_dev->fd, USBDEVFS_SUBMITURB, urb);
871 } while (ret < 0 && errno == EINTR);
873 return ret; /* the caller can read errno to get more info */
875 bytesdone += requested;
876 } while (bytesdone < size);
881 Writes data in chunks (see ftdi_write_data_set_chunksize()) to the chip.
882 Does not wait for completion of the transfer nor does it make sure that
883 the transfer was successful.
885 This function could be extended to use signals and callbacks to inform the
886 caller of completion or error - but this is not done yet, volunteers welcome.
888 Works around libusb and directly accesses functions only available on Linux.
890 \param ftdi pointer to ftdi_context
891 \param buf Buffer with the data
892 \param size Size of the buffer
894 \retval <0: error code from usb_bulk_write()
895 \retval >0: number of bytes written
897 int ftdi_write_data_async(struct ftdi_context *ftdi, unsigned char *buf, int size)
901 int total_written = 0;
903 while (offset < size) {
904 int write_size = ftdi->writebuffer_chunksize;
906 if (offset+write_size > size)
907 write_size = size-offset;
909 ret = _usb_bulk_write_async(ftdi, ftdi->in_ep, buf+offset, write_size);
911 ftdi_error_return(ret, "usb bulk write async failed");
913 total_written += ret;
914 offset += write_size;
917 return total_written;
922 Configure write buffer chunk size.
925 \param ftdi pointer to ftdi_context
926 \param chunksize Chunk size
930 int ftdi_write_data_set_chunksize(struct ftdi_context *ftdi, unsigned int chunksize)
932 ftdi->writebuffer_chunksize = chunksize;
937 Get write buffer chunk size.
939 \param ftdi pointer to ftdi_context
940 \param chunksize Pointer to store chunk size in
944 int ftdi_write_data_get_chunksize(struct ftdi_context *ftdi, unsigned int *chunksize)
946 *chunksize = ftdi->writebuffer_chunksize;
951 Reads data in chunks (see ftdi_read_data_set_chunksize()) from the chip.
953 Automatically strips the two modem status bytes transfered during every read.
955 \param ftdi pointer to ftdi_context
956 \param buf Buffer to store data in
957 \param size Size of the buffer
959 \retval <0: error code from usb_bulk_read()
960 \retval 0: no data was available
961 \retval >0: number of bytes read
963 \remark This function is not useful in bitbang mode.
964 Use ftdi_read_pins() to get the current state of the pins.
966 int ftdi_read_data(struct ftdi_context *ftdi, unsigned char *buf, int size)
968 int offset = 0, ret = 1, i, num_of_chunks, chunk_remains;
970 // everything we want is still in the readbuffer?
971 if (size <= ftdi->readbuffer_remaining) {
972 memcpy (buf, ftdi->readbuffer+ftdi->readbuffer_offset, size);
975 ftdi->readbuffer_remaining -= size;
976 ftdi->readbuffer_offset += size;
978 /* printf("Returning bytes from buffer: %d - remaining: %d\n", size, ftdi->readbuffer_remaining); */
982 // something still in the readbuffer, but not enough to satisfy 'size'?
983 if (ftdi->readbuffer_remaining != 0) {
984 memcpy (buf, ftdi->readbuffer+ftdi->readbuffer_offset, ftdi->readbuffer_remaining);
987 offset += ftdi->readbuffer_remaining;
989 // do the actual USB read
990 while (offset < size && ret > 0) {
991 ftdi->readbuffer_remaining = 0;
992 ftdi->readbuffer_offset = 0;
993 /* returns how much received */
994 ret = usb_bulk_read (ftdi->usb_dev, ftdi->out_ep, ftdi->readbuffer, ftdi->readbuffer_chunksize, ftdi->usb_read_timeout);
996 ftdi_error_return(ret, "usb bulk read failed");
999 // skip FTDI status bytes.
1000 // Maybe stored in the future to enable modem use
1001 num_of_chunks = ret / 64;
1002 chunk_remains = ret % 64;
1003 //printf("ret = %X, num_of_chunks = %X, chunk_remains = %X, readbuffer_offset = %X\n", ret, num_of_chunks, chunk_remains, ftdi->readbuffer_offset);
1005 ftdi->readbuffer_offset += 2;
1009 for (i = 1; i < num_of_chunks; i++)
1010 memmove (ftdi->readbuffer+ftdi->readbuffer_offset+62*i,
1011 ftdi->readbuffer+ftdi->readbuffer_offset+64*i,
1013 if (chunk_remains > 2) {
1014 memmove (ftdi->readbuffer+ftdi->readbuffer_offset+62*i,
1015 ftdi->readbuffer+ftdi->readbuffer_offset+64*i,
1017 ret -= 2*num_of_chunks;
1019 ret -= 2*(num_of_chunks-1)+chunk_remains;
1021 } else if (ret <= 2) {
1022 // no more data to read?
1026 // data still fits in buf?
1027 if (offset+ret <= size) {
1028 memcpy (buf+offset, ftdi->readbuffer+ftdi->readbuffer_offset, ret);
1029 //printf("buf[0] = %X, buf[1] = %X\n", buf[0], buf[1]);
1032 /* Did we read exactly the right amount of bytes? */
1034 //printf("read_data exact rem %d offset %d\n",
1035 //ftdi->readbuffer_remaining, offset);
1038 // only copy part of the data or size <= readbuffer_chunksize
1039 int part_size = size-offset;
1040 memcpy (buf+offset, ftdi->readbuffer+ftdi->readbuffer_offset, part_size);
1042 ftdi->readbuffer_offset += part_size;
1043 ftdi->readbuffer_remaining = ret-part_size;
1044 offset += part_size;
1046 /* printf("Returning part: %d - size: %d - offset: %d - ret: %d - remaining: %d\n",
1047 part_size, size, offset, ret, ftdi->readbuffer_remaining); */
1058 Configure read buffer chunk size.
1061 Automatically reallocates the buffer.
1063 \param ftdi pointer to ftdi_context
1064 \param chunksize Chunk size
1068 int ftdi_read_data_set_chunksize(struct ftdi_context *ftdi, unsigned int chunksize)
1070 unsigned char *new_buf;
1072 // Invalidate all remaining data
1073 ftdi->readbuffer_offset = 0;
1074 ftdi->readbuffer_remaining = 0;
1076 if ((new_buf = (unsigned char *)realloc(ftdi->readbuffer, chunksize)) == NULL)
1077 ftdi_error_return(-1, "out of memory for readbuffer");
1079 ftdi->readbuffer = new_buf;
1080 ftdi->readbuffer_chunksize = chunksize;
1086 Get read buffer chunk size.
1088 \param ftdi pointer to ftdi_context
1089 \param chunksize Pointer to store chunk size in
1093 int ftdi_read_data_get_chunksize(struct ftdi_context *ftdi, unsigned int *chunksize)
1095 *chunksize = ftdi->readbuffer_chunksize;
1101 Enable bitbang mode.
1103 For advanced bitbang modes of the FT2232C chip use ftdi_set_bitmode().
1105 \param ftdi pointer to ftdi_context
1106 \param bitmask Bitmask to configure lines.
1107 HIGH/ON value configures a line as output.
1110 \retval -1: can't enable bitbang mode
1112 int ftdi_enable_bitbang(struct ftdi_context *ftdi, unsigned char bitmask)
1114 unsigned short usb_val;
1116 usb_val = bitmask; // low byte: bitmask
1117 /* FT2232C: Set bitbang_mode to 2 to enable SPI */
1118 usb_val |= (ftdi->bitbang_mode << 8);
1120 if (usb_control_msg(ftdi->usb_dev, 0x40, 0x0B, usb_val, ftdi->index, NULL, 0, ftdi->usb_write_timeout) != 0)
1121 ftdi_error_return(-1, "unable to enter bitbang mode. Perhaps not a BM type chip?");
1123 ftdi->bitbang_enabled = 1;
1128 Disable bitbang mode.
1130 \param ftdi pointer to ftdi_context
1133 \retval -1: can't disable bitbang mode
1135 int ftdi_disable_bitbang(struct ftdi_context *ftdi)
1137 if (usb_control_msg(ftdi->usb_dev, 0x40, 0x0B, 0, ftdi->index, NULL, 0, ftdi->usb_write_timeout) != 0)
1138 ftdi_error_return(-1, "unable to leave bitbang mode. Perhaps not a BM type chip?");
1140 ftdi->bitbang_enabled = 0;
1145 Enable advanced bitbang mode for FT2232C chips.
1147 \param ftdi pointer to ftdi_context
1148 \param bitmask Bitmask to configure lines.
1149 HIGH/ON value configures a line as output.
1150 \param mode Bitbang mode: 1 for normal mode, 2 for SPI mode
1153 \retval -1: can't enable bitbang mode
1155 int ftdi_set_bitmode(struct ftdi_context *ftdi, unsigned char bitmask, unsigned char mode)
1157 unsigned short usb_val;
1159 usb_val = bitmask; // low byte: bitmask
1160 usb_val |= (mode << 8);
1161 if (usb_control_msg(ftdi->usb_dev, 0x40, 0x0B, usb_val, ftdi->index, NULL, 0, ftdi->usb_write_timeout) != 0)
1162 ftdi_error_return(-1, "unable to configure bitbang mode. Perhaps not a 2232C type chip?");
1164 ftdi->bitbang_mode = mode;
1165 ftdi->bitbang_enabled = (mode == BITMODE_BITBANG || mode == BITMODE_SYNCBB)?1:0;
1170 Directly read pin state. Useful for bitbang mode.
1172 \param ftdi pointer to ftdi_context
1173 \param pins Pointer to store pins into
1176 \retval -1: read pins failed
1178 int ftdi_read_pins(struct ftdi_context *ftdi, unsigned char *pins)
1180 if (usb_control_msg(ftdi->usb_dev, 0xC0, 0x0C, 0, ftdi->index, (char *)pins, 1, ftdi->usb_read_timeout) != 1)
1181 ftdi_error_return(-1, "read pins failed");
1189 The FTDI chip keeps data in the internal buffer for a specific
1190 amount of time if the buffer is not full yet to decrease
1191 load on the usb bus.
1193 \param ftdi pointer to ftdi_context
1194 \param latency Value between 1 and 255
1197 \retval -1: latency out of range
1198 \retval -2: unable to set latency timer
1200 int ftdi_set_latency_timer(struct ftdi_context *ftdi, unsigned char latency)
1202 unsigned short usb_val;
1205 ftdi_error_return(-1, "latency out of range. Only valid for 1-255");
1208 if (usb_control_msg(ftdi->usb_dev, 0x40, 0x09, usb_val, ftdi->index, NULL, 0, ftdi->usb_write_timeout) != 0)
1209 ftdi_error_return(-2, "unable to set latency timer");
1217 \param ftdi pointer to ftdi_context
1218 \param latency Pointer to store latency value in
1221 \retval -1: unable to get latency timer
1223 int ftdi_get_latency_timer(struct ftdi_context *ftdi, unsigned char *latency)
1225 unsigned short usb_val;
1226 if (usb_control_msg(ftdi->usb_dev, 0xC0, 0x0A, 0, ftdi->index, (char *)&usb_val, 1, ftdi->usb_read_timeout) != 1)
1227 ftdi_error_return(-1, "reading latency timer failed");
1229 *latency = (unsigned char)usb_val;
1236 \param ftdi pointer to ftdi_context
1237 \param eeprom Pointer to ftdi_eeprom
1241 void ftdi_eeprom_setsize(struct ftdi_context *ftdi, struct ftdi_eeprom *eeprom, int size)
1243 ftdi->eeprom_size=size;
1248 Init eeprom with default values.
1250 \param eeprom Pointer to ftdi_eeprom
1252 void ftdi_eeprom_initdefaults(struct ftdi_eeprom *eeprom)
1254 eeprom->vendor_id = 0x0403;
1255 eeprom->product_id = 0x6001;
1257 eeprom->self_powered = 1;
1258 eeprom->remote_wakeup = 1;
1259 eeprom->BM_type_chip = 1;
1261 eeprom->in_is_isochronous = 0;
1262 eeprom->out_is_isochronous = 0;
1263 eeprom->suspend_pull_downs = 0;
1265 eeprom->use_serial = 0;
1266 eeprom->change_usb_version = 0;
1267 eeprom->usb_version = 0x0200;
1268 eeprom->max_power = 0;
1270 eeprom->manufacturer = NULL;
1271 eeprom->product = NULL;
1272 eeprom->serial = NULL;
1274 eeprom->size = FTDI_DEFAULT_EEPROM_SIZE;
1278 Build binary output from ftdi_eeprom structure.
1279 Output is suitable for ftdi_write_eeprom().
1281 \param eeprom Pointer to ftdi_eeprom
1282 \param output Buffer of 128 bytes to store eeprom image to
1284 \retval >0: used eeprom size
1285 \retval -1: eeprom size (128 bytes) exceeded by custom strings
1287 int ftdi_eeprom_build(struct ftdi_eeprom *eeprom, unsigned char *output)
1290 unsigned short checksum, value;
1291 unsigned char manufacturer_size = 0, product_size = 0, serial_size = 0;
1294 if (eeprom->manufacturer != NULL)
1295 manufacturer_size = strlen(eeprom->manufacturer);
1296 if (eeprom->product != NULL)
1297 product_size = strlen(eeprom->product);
1298 if (eeprom->serial != NULL)
1299 serial_size = strlen(eeprom->serial);
1301 size_check = eeprom->size;
1302 size_check -= 28; // 28 are always in use (fixed)
1304 // Top half of a 256byte eeprom is used just for strings and checksum
1305 // it seems that the FTDI chip will not read these strings from the lower half
1306 // Each string starts with two bytes; offset and type (0x03 for string)
1307 // the checksum needs two bytes, so without the string data that 8 bytes from the top half
1308 if(eeprom->size>=256)size_check = 120;
1309 size_check -= manufacturer_size*2;
1310 size_check -= product_size*2;
1311 size_check -= serial_size*2;
1313 // eeprom size exceeded?
1318 memset (output, 0, eeprom->size);
1320 // Addr 00: Stay 00 00
1321 // Addr 02: Vendor ID
1322 output[0x02] = eeprom->vendor_id;
1323 output[0x03] = eeprom->vendor_id >> 8;
1325 // Addr 04: Product ID
1326 output[0x04] = eeprom->product_id;
1327 output[0x05] = eeprom->product_id >> 8;
1329 // Addr 06: Device release number (0400h for BM features)
1330 output[0x06] = 0x00;
1332 if (eeprom->BM_type_chip == 1)
1333 output[0x07] = 0x04;
1335 output[0x07] = 0x02;
1337 // Addr 08: Config descriptor
1338 // Bit 1: remote wakeup if 1
1339 // Bit 0: self powered if 1
1342 if (eeprom->self_powered == 1)
1344 if (eeprom->remote_wakeup == 1)
1348 // Addr 09: Max power consumption: max power = value * 2 mA
1349 output[0x09] = eeprom->max_power;
1352 // Addr 0A: Chip configuration
1353 // Bit 7: 0 - reserved
1354 // Bit 6: 0 - reserved
1355 // Bit 5: 0 - reserved
1356 // Bit 4: 1 - Change USB version
1357 // Bit 3: 1 - Use the serial number string
1358 // Bit 2: 1 - Enable suspend pull downs for lower power
1359 // Bit 1: 1 - Out EndPoint is Isochronous
1360 // Bit 0: 1 - In EndPoint is Isochronous
1363 if (eeprom->in_is_isochronous == 1)
1365 if (eeprom->out_is_isochronous == 1)
1367 if (eeprom->suspend_pull_downs == 1)
1369 if (eeprom->use_serial == 1)
1371 if (eeprom->change_usb_version == 1)
1375 // Addr 0B: reserved
1376 output[0x0B] = 0x00;
1378 // Addr 0C: USB version low byte when 0x0A bit 4 is set
1379 // Addr 0D: USB version high byte when 0x0A bit 4 is set
1380 if (eeprom->change_usb_version == 1) {
1381 output[0x0C] = eeprom->usb_version;
1382 output[0x0D] = eeprom->usb_version >> 8;
1386 // Addr 0E: Offset of the manufacturer string + 0x80, calculated later
1387 // Addr 0F: Length of manufacturer string
1388 output[0x0F] = manufacturer_size*2 + 2;
1390 // Addr 10: Offset of the product string + 0x80, calculated later
1391 // Addr 11: Length of product string
1392 output[0x11] = product_size*2 + 2;
1394 // Addr 12: Offset of the serial string + 0x80, calculated later
1395 // Addr 13: Length of serial string
1396 output[0x13] = serial_size*2 + 2;
1400 if(eeprom->size>=256) i = 0x80;
1403 // Output manufacturer
1404 output[0x0E] = i | 0x80; // calculate offset
1405 output[i++] = manufacturer_size*2 + 2;
1406 output[i++] = 0x03; // type: string
1407 for (j = 0; j < manufacturer_size; j++) {
1408 output[i] = eeprom->manufacturer[j], i++;
1409 output[i] = 0x00, i++;
1412 // Output product name
1413 output[0x10] = i | 0x80; // calculate offset
1414 output[i] = product_size*2 + 2, i++;
1415 output[i] = 0x03, i++;
1416 for (j = 0; j < product_size; j++) {
1417 output[i] = eeprom->product[j], i++;
1418 output[i] = 0x00, i++;
1422 output[0x12] = i | 0x80; // calculate offset
1423 output[i] = serial_size*2 + 2, i++;
1424 output[i] = 0x03, i++;
1425 for (j = 0; j < serial_size; j++) {
1426 output[i] = eeprom->serial[j], i++;
1427 output[i] = 0x00, i++;
1430 // calculate checksum
1433 for (i = 0; i < eeprom->size/2-1; i++) {
1434 value = output[i*2];
1435 value += output[(i*2)+1] << 8;
1437 checksum = value^checksum;
1438 checksum = (checksum << 1) | (checksum >> 15);
1441 output[eeprom->size-2] = checksum;
1442 output[eeprom->size-1] = checksum >> 8;
1450 \param ftdi pointer to ftdi_context
1451 \param eeprom Pointer to store eeprom into
1454 \retval -1: read failed
1456 int ftdi_read_eeprom(struct ftdi_context *ftdi, unsigned char *eeprom)
1460 for (i = 0; i < ftdi->eeprom_size/2; i++) {
1461 if (usb_control_msg(ftdi->usb_dev, 0xC0, 0x90, 0, i, eeprom+(i*2), 2, ftdi->usb_read_timeout) != 2)
1462 ftdi_error_return(-1, "reading eeprom failed");
1469 ftdi_read_chipid_shift does the bitshift operation needed for the FTDIChip-ID
1470 Function is only used internally
1473 static unsigned char ftdi_read_chipid_shift(unsigned char value)
1475 return ((value & 1) << 1) |
1476 ((value & 2) << 5) |
1477 ((value & 4) >> 2) |
1478 ((value & 8) << 4) |
1479 ((value & 16) >> 1) |
1480 ((value & 32) >> 1) |
1481 ((value & 64) >> 4) |
1482 ((value & 128) >> 2);
1486 Read the FTDIChip-ID from R-type devices
1488 \param ftdi pointer to ftdi_context
1489 \param chipid Pointer to store FTDIChip-ID
1492 \retval -1: read failed
1494 int ftdi_read_chipid(struct ftdi_context *ftdi, unsigned int *chipid)
1496 unsigned int a = 0, b = 0;
1498 if (usb_control_msg(ftdi->usb_dev, 0xC0, 0x90, 0, 0x43, (char *)&a, 2, ftdi->usb_read_timeout) == 2)
1500 a = a << 8 | a >> 8;
1501 if (usb_control_msg(ftdi->usb_dev, 0xC0, 0x90, 0, 0x44, (char *)&b, 2, ftdi->usb_read_timeout) == 2)
1503 b = b << 8 | b >> 8;
1505 a = ftdi_read_chipid_shift(a) | ftdi_read_chipid_shift(a>>8)<<8
1506 | ftdi_read_chipid_shift(a>>16)<<16 | ftdi_read_chipid_shift(a>>24)<<24;
1507 *chipid = a ^ 0xa5f0f7d1;
1512 ftdi_error_return(-1, "read of FTDIChip-ID failed");
1516 Guesses size of eeprom by reading eeprom and comparing halves - will not work with blank eeprom
1517 Call this function then do a write then call again to see if size changes, if so write again.
1519 \param ftdi pointer to ftdi_context
1520 \param eeprom Pointer to store eeprom into
1521 \param maxsize the size of the buffer to read into
1523 \retval size of eeprom
1525 int ftdi_read_eeprom_getsize(struct ftdi_context *ftdi, unsigned char *eeprom, int maxsize)
1527 int i=0,j,minsize=32;
1531 for (j = 0; i < maxsize/2 && j<size; j++) {
1532 if (usb_control_msg(ftdi->usb_dev, 0xC0, 0x90, 0, i, eeprom+(i*2), 2, ftdi->usb_read_timeout) != 2)
1533 ftdi_error_return(-1, "reading eeprom failed");
1537 }while(size<=maxsize && memcmp(eeprom,&eeprom[size/2],size/2)!=0);
1545 \param ftdi pointer to ftdi_context
1546 \param eeprom Pointer to read eeprom from
1549 \retval -1: read failed
1551 int ftdi_write_eeprom(struct ftdi_context *ftdi, unsigned char *eeprom)
1553 unsigned short usb_val;
1556 for (i = 0; i < ftdi->eeprom_size/2; i++) {
1557 usb_val = eeprom[i*2];
1558 usb_val += eeprom[(i*2)+1] << 8;
1559 if (usb_control_msg(ftdi->usb_dev, 0x40, 0x91, usb_val, i, NULL, 0, ftdi->usb_write_timeout) != 0)
1560 ftdi_error_return(-1, "unable to write eeprom");
1569 \param ftdi pointer to ftdi_context
1572 \retval -1: erase failed
1574 int ftdi_erase_eeprom(struct ftdi_context *ftdi)
1576 if (usb_control_msg(ftdi->usb_dev, 0x40, 0x92, 0, 0, NULL, 0, ftdi->usb_write_timeout) != 0)
1577 ftdi_error_return(-1, "unable to erase eeprom");
1583 Get string representation for last error code
1585 \param ftdi pointer to ftdi_context
1587 \retval Pointer to error string
1589 char *ftdi_get_error_string (struct ftdi_context *ftdi)
1591 return ftdi->error_str;
1595 Flow control code by Lorenz Moesenlechner (lorenz@hcilab.org)
1596 and Matthias Kranz (matthias@hcilab.org)
1599 Set flowcontrol for ftdi chip
1601 \param ftdi pointer to ftdi_context
1602 \param flowctrl flow control to use. should be
1603 SIO_DISABLE_FLOW_CTRL, SIO_RTS_CTS_HS, SIO_DTR_DSR_HS or SIO_XON_XOFF_HS
1606 \retval -1: set flow control failed
1608 int ftdi_setflowctrl(struct ftdi_context *ftdi, int flowctrl)
1610 if (usb_control_msg(ftdi->usb_dev, SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1611 SIO_SET_FLOW_CTRL_REQUEST, 0, (flowctrl | ftdi->interface),
1612 NULL, 0, ftdi->usb_write_timeout) != 0)
1613 ftdi_error_return(-1, "set flow control failed");
1621 \param ftdi pointer to ftdi_context
1622 \param state state to set line to (1 or 0)
1625 \retval -1: set dtr failed
1627 int ftdi_setdtr(struct ftdi_context *ftdi, int state)
1629 unsigned short usb_val;
1632 usb_val = SIO_SET_DTR_HIGH;
1634 usb_val = SIO_SET_DTR_LOW;
1636 if (usb_control_msg(ftdi->usb_dev, SIO_SET_MODEM_CTRL_REQUEST_TYPE,
1637 SIO_SET_MODEM_CTRL_REQUEST, usb_val, ftdi->interface,
1638 NULL, 0, ftdi->usb_write_timeout) != 0)
1639 ftdi_error_return(-1, "set dtr failed");
1647 \param ftdi pointer to ftdi_context
1648 \param state state to set line to (1 or 0)
1651 \retval -1 set rts failed
1653 int ftdi_setrts(struct ftdi_context *ftdi, int state)
1655 unsigned short usb_val;
1658 usb_val = SIO_SET_RTS_HIGH;
1660 usb_val = SIO_SET_RTS_LOW;
1662 if (usb_control_msg(ftdi->usb_dev, SIO_SET_MODEM_CTRL_REQUEST_TYPE,
1663 SIO_SET_MODEM_CTRL_REQUEST, usb_val, ftdi->interface,
1664 NULL, 0, ftdi->usb_write_timeout) != 0)
1665 ftdi_error_return(-1, "set of rts failed");
1670 /* @} end of doxygen libftdi group */