make -R default, it doesn't hurt but may improve performance

[hmcfgusb] / hmcfgusb.c

diff --git a/hmcfgusb.c b/hmcfgusb.c
index 0bcb5aeb6ebea87a1a905f6b9ce4d184fc0ba867..f35138f6d7bbe22cddb13bf1b55074de818fc161 100644 (file)
--- a/hmcfgusb.c
+++ b/hmcfgusb.c
@@ -29,6 +29,7 @@
 #include <math.h>
 #include <poll.h>
 #include <errno.h>
+#include <sys/time.h>
 #include <libusb-1.0/libusb.h>
 
 #include "hexdump.h"
@@ -139,13 +140,33 @@ static libusb_device_handle *hmcfgusb_find() {
        return NULL;
 }
 
+int hmcfgusb_send_null_frame(struct hmcfgusb_dev *usbdev)
+{
+       int err;
+       int cnt;
+
+       err = libusb_interrupt_transfer(usbdev->usb_devh, EP_OUT, NULL, 0, &cnt, USB_TIMEOUT);
+       if (err) {
+               fprintf(stderr, "Can't send data: %s\n", usb_strerror(err));
+               return 0;
+       }
+
+       return 1;
+}
+
 int hmcfgusb_send(struct hmcfgusb_dev *usbdev, unsigned char* send_data, int len, int done)
 {
        int err;
        int cnt;
+       struct timeval tv_start, tv_end;
+       int msec;
 
-       if (debug)
+       if (debug) {
                hexdump(send_data, len, "USB < ");
+       }
+
+       gettimeofday(&tv_start, NULL);
+
        err = libusb_interrupt_transfer(usbdev->usb_devh, EP_OUT, send_data, len, &cnt, USB_TIMEOUT);
        if (err) {
                fprintf(stderr, "Can't send data: %s\n", usb_strerror(err));
@@ -153,13 +174,20 @@ int hmcfgusb_send(struct hmcfgusb_dev *usbdev, unsigned char* send_data, int len
        }
 
        if (done) {
-               err = libusb_interrupt_transfer(usbdev->usb_devh, EP_OUT, send_data, 0, &cnt, USB_TIMEOUT);
-               if (err) {
-                       fprintf(stderr, "Can't send data: %s\n", usb_strerror(err));
+               if (!hmcfgusb_send_null_frame(usbdev)) {
                        return 0;
                }
        }
 
+       gettimeofday(&tv_end, NULL);
+       msec = ((tv_end.tv_sec-tv_start.tv_sec)*1000)+((tv_end.tv_usec-tv_start.tv_usec)/1000);
+
+       if (msec > 100) {
+               fprintf(stderr, "usb-transfer took more than 100ms (%dms), this may lead to timing problems!\n", msec);
+       } else if (debug) {
+               fprintf(stderr, "usb-transfer took %dms!\n", msec);
+       }
+
        return 1;
 }