[Libusb-devel] Trying to speak to my USB device

[<min...@gm...>]

Hi,

I am currently trying to get a specific type of USB data cable I own to
work in Linux.  Starting from a trace obtained on Windows using
USBTrace, I began writing an implementation using libusb.  Opening and
claiming the device works fine, but after that I am somewhat stuck.  The
actual data transfers should work with usb_bulk_write/usb_bulk_read, but
reading currently gives me a timeout, so I suspect I have to perform
some of the control requests first.  That, however, doesn't seem to
work.  Starting with the first request in my trace:

--------- Request # 1 ----[OUT]----
URB_FUNCTION_VENDOR_INTERFACE

IRP: 0x81C13D30
Status: STATUS_SUCCESS (0x0)
Device Object: 0x81CB6AA0

Length: 0x50
USBD Status: USBD_STATUS_PENDING (0x40000000)
TransferFlags: 0x0 ( USBD_TRANSFER_DIRECTION_OUT )
TransferBufferLength: 0x0
TransferBuffer: 0x0
TransferBufferMDL: 0x0
UrbLink: 0x0
RequestType: 0x0 (Direction: Host-to-device, Type: Standard, Recipient:
Device)
Request: 0x11
Value: 0x0
Index: 0x0
-----------------------------------

I expected to be able to write this as
  usb_control_msg(handle, USB_ENDPOINT_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
                  0x11, 0x0, 0x0, 0, 0, 10);

This (and any attempts to reproduce other traced
URB_FUNCTION_VENDOR_INTERFACE calls) fails with a Broken Pipe error.

I am (as you can probably tell) new to USB-related programming, so maybe
I'm already interpreting this trace wrong.  I could not think of any
other way to implement it though.

Do you have any ideas of what I am doing wrong or what I am missing?

Thanks in advance for your help,

Jan