On Sun, 8 Jul 2007, Phil Dibowitz wrote: > With a bit of help, I've found the device has a handful of standard "Vendor" > control commands. But when I try to send them with usb_control_msg(), I'm > getting back 'Broken pipe'. > > The only thing I can think of is that I'm not assembling my requestType > right, but it seems right to me. I'm doing this (keep in mind I'm using > libusb, not in-kernel USB... but for usb_control_msg() they should be the > same except for request and requestType are switched in order of parameters): > > int retval; > int len = 100; > int timeout = 1000; > char buf[len]; > retval = usb_control_msg(udev, > USB_ENDPOINT_IN + USB_TYPE_VENDOR + USB_RECIP_INTERFACE, > COMMAND_GET_VERSION, 0, DEVICE_INT, buf, len, timeout); > > I've also tried that with USB_RECIP_DEVICE and USB_RECIP_ENDPOINT. > COMMAND_GET_VERSION is a #define for 0x10. DEVICE_INT is a #define for 0. > > This fails and usb_strerror() is "Broken pipe"... however, I can do > "standard" commands like: > > int retval; > int len; > len = 2; > char buf[len]; > retval = usb_control_msg(udev, > GET_STATUS_TYPE, GET_STATUS,0,0,buf,len,1000); > > GET_STATUS_TYPE is 0x80 (or USB_ENDPOINT_IN + USB_TYPE_STANDARD + > USB_RECIP_DEVICE) and GET_STATUS is 0x00, as found in several drivers in the > USB kernel tree. > > Am I doing something obviously wrong here? If not, I'm probably > misunderstanding how the device works, but before I spin my wheels too long, > I thought I'd see if I was making some obvious mistake.
Use usbmon. Compare what your program does with the Windows packet traces. Alan Stern ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
