--- /dev/null
+/***************************************************************************
+ ftdi_stream.c - description
+ -------------------
+ copyright : (C) 2009 Micah Dowty 2010 Uwe Bonnes
+ email : opensource@intra2net.com
+ ***************************************************************************/
+
+/***************************************************************************
+ * *
+ * This program is free software; you can redistribute it and/or modify *
+ * it under the terms of the GNU Lesser General Public License *
+ * version 2.1 as published by the Free Software Foundation; *
+ * *
+ ***************************************************************************/
+
+/* Adapted from
+ * fastftdi.c - A minimal FTDI FT232H interface for which supports bit-bang
+ * mode, but focuses on very high-performance support for
+ * synchronous FIFO mode. Requires libusb-1.0
+ *
+ * Copyright (C) 2009 Micah Dowty
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "ftdi.h"
+
+typedef struct
+{
+ FTDIStreamCallback *callback;
+ void *userdata;
+ int packetsize;
+ int result;
+ FTDIProgressInfo progress;
+} FTDIStreamState;
+
+static void
+ftdi_readstream_cb(struct libusb_transfer *transfer)
+{
+ FTDIStreamState *state = transfer->user_data;
+ int packet_size = state->packetsize;
+
+ if(transfer->status & LIBUSB_TRANSFER_CANCELLED)
+ {
+ free(transfer->buffer);
+ libusb_free_transfer(transfer);
+ return;
+ }
+ if (state->result == 0)
+ {
+ if (transfer->status == LIBUSB_TRANSFER_COMPLETED)
+ {
+ int i;
+ uint8_t *ptr = transfer->buffer;
+ int length = transfer->actual_length;
+ int numPackets = (length + packet_size - 1) / packet_size;
+
+ for (i = 0; i < numPackets; i++)
+ {
+ int payloadLen;
+ int packetLen = length;
+
+ if (packetLen > packet_size)
+ packetLen = packet_size;
+
+ payloadLen = packetLen - 2;
+ state->progress.current.totalBytes += payloadLen;
+
+ state->result = state->callback(ptr + 2, payloadLen,
+ NULL, state->userdata);
+ if (state->result)
+ break;
+
+ ptr += packetLen;
+ length -= packetLen;
+ }
+
+
+ }
+ else
+ {
+ fprintf(stderr, "unknown status %d\n",transfer->status);
+ state->result = LIBUSB_ERROR_IO;
+ }
+ }
+ else
+ fprintf(stderr,"state->result %d\n", state->result);
+
+ if (state->result == 0)
+ {
+ transfer->status = -1;
+ state->result = libusb_submit_transfer(transfer);
+ }
+}
+
+/**
+ Helper function to calculate (unix) time differences
+
+ \param a timeval
+ \param b timeval
+*/
+static double
+TimevalDiff(const struct timeval *a, const struct timeval *b)
+{
+ return (a->tv_sec - b->tv_sec) + 1e-6 * (a->tv_usec - b->tv_usec);
+}
+
+/**
+ Streaming reading of data from the device
+
+ Use asynchronous transfers in libusb-1.0 for high-performance
+ streaming of data from a device interface back to the PC. This
+ function continuously transfers data until either an error occurs
+ or the callback returns a nonzero value. This function returns
+ a libusb error code or the callback's return value.
+
+ For every contiguous block of received data, the callback will
+ be invoked.
+
+ \param ftdi pointer to ftdi_context
+ \param callback to user supplied function for one block of data
+ \param userdata
+ \param packetsPerTransfer number of packets per transfer
+ \param numTransfers Number of transfers per callback
+
+*/
+
+int
+ftdi_readstream(struct ftdi_context *ftdi,
+ FTDIStreamCallback *callback, void *userdata,
+ int packetsPerTransfer, int numTransfers)
+{
+ struct libusb_transfer **transfers;
+ FTDIStreamState state = { callback, userdata, ftdi->max_packet_size };
+ int bufferSize = packetsPerTransfer * ftdi->max_packet_size;
+ int xferIndex;
+ int err = 0;
+
+ fprintf(stderr, "ftdi_readstream\n");
+ /*
+ * Set up all transfers
+ */
+
+ transfers = calloc(numTransfers, sizeof *transfers);
+ if (!transfers) {
+ err = LIBUSB_ERROR_NO_MEM;
+ goto cleanup;
+ }
+
+ for (xferIndex = 0; xferIndex < numTransfers; xferIndex++)
+ {
+ struct libusb_transfer *transfer;
+
+ transfer = libusb_alloc_transfer(0);
+ transfers[xferIndex] = transfer;
+ if (!transfer) {
+ err = LIBUSB_ERROR_NO_MEM;
+ goto cleanup;
+ }
+
+ libusb_fill_bulk_transfer(transfer, ftdi->usb_dev, ftdi->out_ep,
+ malloc(bufferSize), bufferSize,
+ ftdi_readstream_cb,
+ &state, 0);
+
+ if (!transfer->buffer) {
+ err = LIBUSB_ERROR_NO_MEM;
+ goto cleanup;
+ }
+
+ transfer->status = -1;
+ err = libusb_submit_transfer(transfer);
+ if (err)
+ goto cleanup;
+ }
+
+ /* Start the transfers only when everything has been set up.
+ * Otherwise the transfers start stuttering and the PC not
+ * fetching data for several to several ten milliseconds
+ * and we skip blocks
+ */
+ if (ftdi_set_bitmode(ftdi, 0xff, BITMODE_SYNCFF) < 0)
+ {
+ fprintf(stderr,"Can't set synchronous fifo mode\n",
+ ftdi_get_error_string(ftdi));
+ goto cleanup;
+ }
+
+ /*
+ * Run the transfers, and periodically assess progress.
+ */
+
+ gettimeofday(&state.progress.first.time, NULL);
+
+ do
+ {
+ FTDIProgressInfo *progress = &state.progress;
+ const double progressInterval = 1.0;
+ struct timeval timeout = { 0, ftdi->usb_read_timeout };
+ struct timeval now;
+
+ int err = libusb_handle_events_timeout(NULL, &timeout);
+ if (!state.result)
+ {
+ state.result = err;
+ }
+
+ // If enough time has elapsed, update the progress
+ gettimeofday(&now, NULL);
+ if (TimevalDiff(&now, &progress->current.time) >= progressInterval)
+ {
+ progress->current.time = now;
+ progress->totalTime = TimevalDiff(&progress->current.time,
+ &progress->first.time);
+
+ if (progress->prev.totalBytes)
+ {
+ // We have enough information to calculate rates
+
+ double currentTime;
+
+ currentTime = TimevalDiff(&progress->current.time,
+ &progress->prev.time);
+
+ progress->totalRate =
+ progress->current.totalBytes /progress->totalTime;
+ progress->currentRate =
+ (progress->current.totalBytes -
+ progress->prev.totalBytes) / currentTime;
+ }
+
+ state.result = state.callback(NULL, 0, progress, state.userdata);
+ progress->prev = progress->current;
+
+ }
+ } while (!state.result);
+
+ /*
+ * Cancel any outstanding transfers, and free memory.
+ */
+
+ cleanup:
+ fprintf(stderr, "cleanup\n");
+ if (transfers) {
+ int i;
+ for (xferIndex = 0; xferIndex < numTransfers; xferIndex++)
+ {
+ struct libusb_transfer *transfer = transfers[xferIndex];
+
+ if (transfer) {
+ libusb_cancel_transfer(transfer);
+ }
+ }
+ libusb_handle_events(NULL);
+ free(transfers);
+ }
+
+ if (err)
+ return err;
+ else
+ return state.result;
+}
+
git://developer.intra2net.com / libftdi / blobdiff