Working on iso

usb/device.go

@@ -15,7 +15,7 @@ import (
 
 var DefaultReadTimeout = 1 * time.Second
 var DefaultWriteTimeout = 1 * time.Second
-var DefaultControlTimeout = 5 * time.Second
+var DefaultControlTimeout = 250 * time.Millisecond //5 * time.Second
 
 type Device struct {
 	handle *C.libusb_device_handle

usb/endpoint.go

@@ -25,7 +25,7 @@ type endpoint struct {
 }
 
 func (e *endpoint) Read(buf []byte) (int, error) {
-	if EndpointDirection(e.Address)&ENDPOINT_DIR_MASK != ENDPOINT_DIR_OUT {
+	if EndpointDirection(e.Address)&ENDPOINT_DIR_MASK != ENDPOINT_DIR_IN {
 		return 0, fmt.Errorf("usb: read: not an IN endpoint")
 	}
 
@@ -40,8 +40,8 @@ func (e *endpoint) Write(buf []byte) (int, error) {
 	return e.xfer(e, buf, e.WriteTimeout)
 }
 
-func (e *endpoint) Interface() InterfaceSetup { return InterfaceSetup{} }
-func (e *endpoint) Info() EndpointInfo        { return EndpointInfo{} }
+func (e *endpoint) Interface() InterfaceSetup { return e.InterfaceSetup }
+func (e *endpoint) Info() EndpointInfo        { return e.EndpointInfo }
 
 // TODO(kevlar): (*Endpoint).Close
 

usb/iso.c

@@ -1,9 +1,49 @@
 #include <libusb-1.0/libusb.h>
+#include <stdio.h>
+#include <string.h>
 
-void _callback(struct libusb_transfer *xfer) {
+void print_xfer(struct libusb_transfer *xfer);
+
+void callback(struct libusb_transfer *xfer) {
+	printf("Callback!\n");
+	print_xfer(xfer);
 	iso_callback(xfer->user_data);
 }
 
-libusb_transfer_cb_fn callback() {
-  return &_callback;
+int submit(struct libusb_transfer *xfer) {
+	xfer->callback = &callback;
+	xfer->status = -1;
+	//print_xfer(xfer);
+	printf("Transfer submitted\n");
+
+	/* fake
+	strcpy(xfer->buffer, "hello");
+	xfer->actual_length = 5;
+	callback(xfer);
+	return 0; */
+	return libusb_submit_transfer(xfer);
+}
+
+void print_xfer(struct libusb_transfer *xfer) {
+	int i;
+
+	printf("Transfer:\n");
+	//printf("  dev_handle:   %p\n", xfer->dev_handle);
+	//printf("  flags:        %08x\n", xfer->flags);
+	printf("  endpoint:     %x\n", xfer->endpoint);
+	//printf("  type:         %x\n", xfer->type);
+	printf("  timeout:      %dms\n", xfer->timeout);
+	printf("  status:       %x\n", xfer->status);
+	printf("  length:       %d (%d)\n", xfer->length, xfer->actual_length);
+	//printf("  callback:     %p\n", xfer->callback);
+	//printf("  user_data:    %p\n", xfer->user_data);
+	//printf("  buffer:       %p\n", xfer->buffer);
+	printf("  num_iso_pkts: %d\n", xfer->num_iso_packets);
+	printf("  packets:\n");
+	for (i = 0; i < xfer->num_iso_packets; i++) {
+		printf("    [%04d] %d (%d) %x\n", i,
+			xfer->iso_packet_desc[i].length,
+			xfer->iso_packet_desc[i].actual_length,
+			xfer->iso_packet_desc[i].status);
+	}
 }

usb/iso.go

@@ -3,12 +3,13 @@ package usb
 /*
 #include <libusb-1.0/libusb.h>
 
-libusb_transfer_cb_fn callback();
+int submit(struct libusb_transfer *xfer);
 */
 import "C"
 
 import (
 	"log"
+	"fmt"
 	"reflect"
 	"runtime"
 	"time"
@@ -24,8 +25,8 @@ func iso_callback(cptr unsafe.Pointer) {
 func (end *endpoint) allocTransfer() *Transfer {
 	// Use libusb_get_max_iso_packet_size ?
 	const (
-		iso_packets = 242
-		packet_size = 1760
+		iso_packets = 8 // 128 // 242
+		packet_size = 2048 // 1760
 	)
 
 	xfer := C.libusb_alloc_transfer(C.int(iso_packets))
@@ -34,27 +35,26 @@ func (end *endpoint) allocTransfer() *Transfer {
 		return nil
 	}
 
+	buf := make([]byte, iso_packets*packet_size)
+	done := make(chan struct{}, 1)
+
 	xfer.dev_handle = end.Device.handle
 	xfer.endpoint = C.uchar(end.Address)
 	xfer._type = C.LIBUSB_TRANSFER_TYPE_ISOCHRONOUS
 
-	xfer.callback = C.callback()
-	xfer.timeout = C.uint(5 * time.Second / time.Millisecond)
-
-	buf := make([]byte, iso_packets*packet_size)
-	xfer.num_iso_packets = iso_packets
 	xfer.buffer = (*C.uchar)((unsafe.Pointer)(&buf[0]))
 	xfer.length = C.int(len(buf))
-	C.libusb_set_iso_packet_lengths(xfer, C.uint(len(buf)))
+	xfer.num_iso_packets = iso_packets
+
+	xfer.user_data = (unsafe.Pointer)(&done)
+
+	C.libusb_set_iso_packet_lengths(xfer, packet_size)
 	pkts := *(*[]C.struct_libusb_packet_descriptor)(unsafe.Pointer(&reflect.SliceHeader{
 		Data: uintptr(unsafe.Pointer(&xfer.iso_packet_desc)),
 		Len:  iso_packets,
 		Cap:  iso_packets,
 	}))
 
-	done := make(chan struct{})
-	xfer.user_data = (unsafe.Pointer)(&done)
-
 	t := &Transfer{
 		xfer: xfer,
 		pkts: pkts,
@@ -74,34 +74,48 @@ type Transfer struct {
 	buf  []byte
 }
 
-func (xfer *Transfer) Submit() error {
-	if errno := C.libusb_submit_transfer(xfer.xfer); errno < 0 {
+func (t *Transfer) Submit(timeout time.Duration) error {
+	log.Printf("iso: submitting %#v", t.xfer)
+	t.xfer.timeout = C.uint(timeout / time.Millisecond)
+	if errno := C.submit(t.xfer); errno < 0 {
 		return usbError(errno)
 	}
 	return nil
 }
 
-func (xfer *Transfer) Wait() (n int, err error) {
-	<-xfer.done
-	n = int(xfer.xfer.actual_length)
-	for _, pkt := range xfer.pkts {
-		log.Printf("PACKET[%4d] - %#v", pkt)
+func (t *Transfer) Wait(b []byte) (n int, err error) {
+	select {
+	case <-time.After(10*time.Second):
+		return 0, fmt.Errorf("wait timed out after 10s")
+	case <-t.done:
 	}
+	n = int(t.xfer.actual_length)
+	copy(b, ((*[1<<16]byte)(unsafe.Pointer(t.xfer.buffer)))[:n])
+	/*
+	for i, pkt := range t.pkts {
+		log.Printf("PACKET[%4d] - %#v", i, pkt)
+	}*/
 	return n, err
 }
 
-func (xfer *Transfer) Close() error {
-	C.libusb_free_transfer(xfer.xfer)
+func (t *Transfer) Close() error {
+	C.libusb_free_transfer(t.xfer)
 	return nil
 }
 
 func isochronous_xfer(e *endpoint, buf []byte, timeout time.Duration) (int, error) {
-	xfer := e.allocTransfer()
-	defer xfer.Close()
+	t := e.allocTransfer()
+	defer t.Close()
 
-	if err := xfer.Submit(); err != nil {
+	if err := t.Submit(timeout); err != nil {
+		log.Printf("iso: xfer failed to submit: %s", err)
 		return 0, err
 	}
 
-	return xfer.Wait()
+	n, err := t.Wait(buf)
+	if err != nil {
+		log.Printf("iso: xfer failed: %s", err)
+		return 0, err
+	}
+	return n, err
 }