1 /***************************************************************************
2 ftdi_stream.c - description
4 copyright : (C) 2009 Micah Dowty 2010 Uwe Bonnes
5 email : opensource@intra2net.com
6 ***************************************************************************/
8 /***************************************************************************
10 * This program is free software; you can redistribute it and/or modify *
11 * it under the terms of the GNU Lesser General Public License *
12 * version 2.1 as published by the Free Software Foundation; *
14 ***************************************************************************/
17 * fastftdi.c - A minimal FTDI FT232H interface for which supports bit-bang
18 * mode, but focuses on very high-performance support for
19 * synchronous FIFO mode. Requires libusb-1.0
21 * Copyright (C) 2009 Micah Dowty
23 * Permission is hereby granted, free of charge, to any person obtaining a copy
24 * of this software and associated documentation files (the "Software"), to deal
25 * in the Software without restriction, including without limitation the rights
26 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
27 * copies of the Software, and to permit persons to whom the Software is
28 * furnished to do so, subject to the following conditions:
30 * The above copyright notice and this permission notice shall be included in
31 * all copies or substantial portions of the Software.
33 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
34 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
35 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
36 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
37 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
38 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
53 FTDIStreamCallback *callback;
58 FTDIProgressInfo progress;
63 * With Exit request, free memory and release the transfer
65 * state->result is only set when some error happens
67 static void LIBUSB_CALL
68 ftdi_readstream_cb(struct libusb_transfer *transfer)
70 FTDIStreamState *state = transfer->user_data;
71 int packet_size = state->packetsize;
74 if (transfer->status == LIBUSB_TRANSFER_COMPLETED)
77 uint8_t *ptr = transfer->buffer;
78 int length = transfer->actual_length;
79 int numPackets = (length + packet_size - 1) / packet_size;
82 for (i = 0; i < numPackets; i++)
85 int packetLen = length;
87 if (packetLen > packet_size)
88 packetLen = packet_size;
90 payloadLen = packetLen - 2;
91 state->progress.current.totalBytes += payloadLen;
93 res = state->callback(ptr + 2, payloadLen,
94 NULL, state->userdata);
101 free(transfer->buffer);
102 libusb_free_transfer(transfer);
106 transfer->status = -1;
107 state->result = libusb_submit_transfer(transfer);
112 fprintf(stderr, "unknown status %d\n",transfer->status);
113 state->result = LIBUSB_ERROR_IO;
118 Helper function to calculate (unix) time differences
124 TimevalDiff(const struct timeval *a, const struct timeval *b)
126 return (a->tv_sec - b->tv_sec) + 1e-6 * (a->tv_usec - b->tv_usec);
130 Streaming reading of data from the device
132 Use asynchronous transfers in libusb-1.0 for high-performance
133 streaming of data from a device interface back to the PC. This
134 function continuously transfers data until either an error occurs
135 or the callback returns a nonzero value. This function returns
136 a libusb error code or the callback's return value.
138 For every contiguous block of received data, the callback will
141 \param ftdi pointer to ftdi_context
142 \param callback to user supplied function for one block of data
144 \param packetsPerTransfer number of packets per transfer
145 \param numTransfers Number of transfers per callback
150 ftdi_readstream(struct ftdi_context *ftdi,
151 FTDIStreamCallback *callback, void *userdata,
152 int packetsPerTransfer, int numTransfers)
154 struct libusb_transfer **transfers;
155 FTDIStreamState state = { callback, userdata, ftdi->max_packet_size, 1 };
156 int bufferSize = packetsPerTransfer * ftdi->max_packet_size;
160 /* Only FT2232H and FT232H know about the synchronous FIFO Mode*/
161 if ((ftdi->type != TYPE_2232H) && (ftdi->type != TYPE_232H))
163 fprintf(stderr,"Device doesn't support synchronous FIFO mode\n");
167 /* We don't know in what state we are, switch to reset*/
168 if (ftdi_set_bitmode(ftdi, 0xff, BITMODE_RESET) < 0)
170 fprintf(stderr,"Can't reset mode\n");
174 /* Purge anything remaining in the buffers*/
175 if (ftdi_usb_purge_buffers(ftdi) < 0)
177 fprintf(stderr,"Can't Purge\n");
182 * Set up all transfers
185 transfers = calloc(numTransfers, sizeof *transfers);
188 err = LIBUSB_ERROR_NO_MEM;
192 for (xferIndex = 0; xferIndex < numTransfers; xferIndex++)
194 struct libusb_transfer *transfer;
196 transfer = libusb_alloc_transfer(0);
197 transfers[xferIndex] = transfer;
200 err = LIBUSB_ERROR_NO_MEM;
204 libusb_fill_bulk_transfer(transfer, ftdi->usb_dev, ftdi->out_ep,
205 malloc(bufferSize), bufferSize,
209 if (!transfer->buffer)
211 err = LIBUSB_ERROR_NO_MEM;
215 transfer->status = -1;
216 err = libusb_submit_transfer(transfer);
221 /* Start the transfers only when everything has been set up.
222 * Otherwise the transfers start stuttering and the PC not
223 * fetching data for several to several ten milliseconds
226 if (ftdi_set_bitmode(ftdi, 0xff, BITMODE_SYNCFF) < 0)
228 fprintf(stderr,"Can't set synchronous fifo mode: %s\n",
229 ftdi_get_error_string(ftdi));
234 * Run the transfers, and periodically assess progress.
237 gettimeofday(&state.progress.first.time, NULL);
241 FTDIProgressInfo *progress = &state.progress;
242 const double progressInterval = 1.0;
243 struct timeval timeout = { 0, ftdi->usb_read_timeout * 1000};
246 int err = libusb_handle_events_timeout(ftdi->usb_ctx, &timeout);
247 if (err == LIBUSB_ERROR_INTERRUPTED)
248 /* restart interrupted events */
249 err = libusb_handle_events_timeout(ftdi->usb_ctx, &timeout);
254 if (state.activity == 0)
259 // If enough time has elapsed, update the progress
260 gettimeofday(&now, NULL);
261 if (TimevalDiff(&now, &progress->current.time) >= progressInterval)
263 progress->current.time = now;
264 progress->totalTime = TimevalDiff(&progress->current.time,
265 &progress->first.time);
267 if (progress->prev.totalBytes)
269 // We have enough information to calculate rates
273 currentTime = TimevalDiff(&progress->current.time,
274 &progress->prev.time);
276 progress->totalRate =
277 progress->current.totalBytes /progress->totalTime;
278 progress->currentRate =
279 (progress->current.totalBytes -
280 progress->prev.totalBytes) / currentTime;
283 state.callback(NULL, 0, progress, state.userdata);
284 progress->prev = progress->current;
287 } while (!state.result);
290 * Cancel any outstanding transfers, and free memory.
294 fprintf(stderr, "cleanup\n");