3 Replies Latest reply on Mar 20, 2013 11:54 PM by @live.cn

    do bulk transfer using libusb on Linux 3.0 port can not work well

    @live.cn

      OS: Centos 6.2
      Kernel: 2.6.32
      Controller: NEC Corporation uPD720200 USB3.0 controller

      when using "libusb_bulk_transfer()" to get 16MB data from device (using 16 times, ask for 1MB at once), returned error code -99 (other error), use "dmesg" can found the following information:

      usb 7-1: usbfs: process 6833 (test) did not claim interface 0 before use
      xhci_hcd 0000:01:00.0: ERROR no room on ep ring
      usb 7-1: usbfs: usb_submit_urb returned -12

      the strange is that when add a wait for 1s between each time,the function return success.

      (on usb2.0 port, it can work well)