--- /dev/null
+/*
+ * libusb example program to measure Atmel SAM3U isochronous performance
+ * Copyright (C) 2012 Harald Welte <laforge@gnumonks.org>
+ *
+ * Copied with the author's permission under LGPL-2.1 from
+ * http://git.gnumonks.org/cgi-bin/gitweb.cgi?p=sam3u-tests.git;a=blob;f=usb-benchmark-project/host/benchmark.c;h=74959f7ee88f1597286cd435f312a8ff52c56b7e
+ *
+ * An Atmel SAM3U test firmware is also available in the above repository.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <signal.h>
+
+#include <libusb.h>
+
+
+#define EP_DATA_IN 0x82
+#define EP_ISO_IN 0x86
+
+static int do_exit = 0;
+static struct libusb_device_handle *devh = NULL;
+
+static unsigned long num_bytes = 0, num_xfer = 0;
+static struct timeval tv_start;
+
+static void LIBUSB_CALL cb_xfr(struct libusb_transfer *xfr)
+{
+ int i;
+
+ if (xfr->status != LIBUSB_TRANSFER_COMPLETED) {
+ fprintf(stderr, "transfer status %d\n", xfr->status);
+ libusb_free_transfer(xfr);
+ exit(3);
+ }
+
+ if (xfr->type == LIBUSB_TRANSFER_TYPE_ISOCHRONOUS) {
+ for (i = 0; i < xfr->num_iso_packets; i++) {
+ struct libusb_iso_packet_descriptor *pack = &xfr->iso_packet_desc[i];
+
+ if (pack->status != LIBUSB_TRANSFER_COMPLETED) {
+ fprintf(stderr, "Error: pack %u status %d\n", i, pack->status);
+ exit(5);
+ }
+
+ printf("pack%u length:%u, actual_length:%u\n", i, pack->length, pack->actual_length);
+ }
+ }
+
+ printf("length:%u, actual_length:%u\n", xfr->length, xfr->actual_length);
+ for (i = 0; i < xfr->actual_length; i++) {
+ printf("%02x", xfr->buffer[i]);
+ if (i % 16)
+ printf("\n");
+ else if (i % 8)
+ printf(" ");
+ else
+ printf(" ");
+ }
+ num_bytes += xfr->actual_length;
+ num_xfer++;
+
+ if (libusb_submit_transfer(xfr) < 0) {
+ fprintf(stderr, "error re-submitting URB\n");
+ exit(1);
+ }
+}
+
+static int benchmark_in(uint8_t ep)
+{
+ static uint8_t buf[2048];
+ static struct libusb_transfer *xfr;
+ int num_iso_pack = 0;
+
+ if (ep == EP_ISO_IN)
+ num_iso_pack = 16;
+
+ xfr = libusb_alloc_transfer(num_iso_pack);
+ if (!xfr)
+ return -ENOMEM;
+
+ if (ep == EP_ISO_IN) {
+ libusb_fill_iso_transfer(xfr, devh, ep, buf,
+ sizeof(buf), num_iso_pack, cb_xfr, NULL, 0);
+ libusb_set_iso_packet_lengths(xfr, sizeof(buf)/num_iso_pack);
+ } else
+ libusb_fill_bulk_transfer(xfr, devh, ep, buf,
+ sizeof(buf), cb_xfr, NULL, 0);
+
+ gettimeofday(&tv_start, NULL);
+
+ /* NOTE: To reach maximum possible performance the program must
+ * submit *multiple* transfers here, not just one.
+ *
+ * When only one transfer is submitted there is a gap in the bus
+ * schedule from when the transfer completes until a new transfer
+ * is submitted by the callback. This causes some jitter for
+ * isochronous transfers and loss of throughput for bulk transfers.
+ *
+ * This is avoided by queueing multiple transfers in advance, so
+ * that the host controller is always kept busy, and will schedule
+ * more transfers on the bus while the callback is running for
+ * transfers which have completed on the bus.
+ */
+
+ return libusb_submit_transfer(xfr);
+}
+
+static void measure(void)
+{
+ struct timeval tv_stop;
+ unsigned int diff_msec;
+
+ gettimeofday(&tv_stop, NULL);
+
+ diff_msec = (tv_stop.tv_sec - tv_start.tv_sec)*1000;
+ diff_msec += (tv_stop.tv_usec - tv_start.tv_usec)/1000;
+
+ printf("%lu transfers (total %lu bytes) in %u miliseconds => %lu bytes/sec\n",
+ num_xfer, num_bytes, diff_msec, (num_bytes*1000)/diff_msec);
+}
+
+static void sig_hdlr(int signum)
+{
+ switch (signum) {
+ case SIGINT:
+ measure();
+ do_exit = 1;
+ break;
+ }
+}
+
+int main(int argc, char **argv)
+{
+ int rc;
+ struct sigaction sigact;
+
+ sigact.sa_handler = sig_hdlr;
+ sigemptyset(&sigact.sa_mask);
+ sigact.sa_flags = 0;
+ sigaction(SIGINT, &sigact, NULL);
+
+ rc = libusb_init(NULL);
+ if (rc < 0) {
+ fprintf(stderr, "Error initializing libusb: %s\n", libusb_error_name(rc));
+ exit(1);
+ }
+
+ devh = libusb_open_device_with_vid_pid(NULL, 0x16c0, 0x0763);
+ if (!devh) {
+ fprintf(stderr, "Error finding USB device\n");
+ goto out;
+ }
+
+ rc = libusb_claim_interface(devh, 2);
+ if (rc < 0) {
+ fprintf(stderr, "Error claiming interface: %s\n", libusb_error_name(rc));
+ goto out;
+ }
+
+ benchmark_in(EP_ISO_IN);
+
+ while (!do_exit) {
+ rc = libusb_handle_events(NULL);
+ if (rc != LIBUSB_SUCCESS)
+ break;
+ }
+
+ /* Measurement has already been done by the signal handler. */
+
+ libusb_release_interface(devh, 0);
+out:
+ if (devh)
+ libusb_close(devh);
+ libusb_exit(NULL);
+ return rc;
+}
projects / rtmpclient.git / blobdiff