1. 19 Oct, 2017 33 commits
  2. 11 Oct, 2017 2 commits
    • Alan Stern's avatar
      USB: dummy-hcd: remove unsupported isochronous endpoints · c9f20aaf
      Alan Stern authored
      The dummy-hcd driver doesn't support emulation of isochronous
      transfers.  Therefore it doesn't need to export isochronous endpoint
      descriptors; they can be commented out.
      
      Also, the comments in the source code don't express clearly enough the
      fact that isochronous isn't supported.  They need to be more explicit.
      
      Finally, change the error status value we use (in theory) for
      isochronous URBs.  checkpatch complains about ENOSYS; EINVAL is more
      appropriate (it is documented to mean "ISO madness").
      Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
      Reported-by: default avatarFelipe Balbi <felipe.balbi@linux.intel.com>
      Signed-off-by: default avatarFelipe Balbi <felipe.balbi@linux.intel.com>
      c9f20aaf
    • Alan Stern's avatar
      USB: dummy-hcd: bandwidth limits for non-bulk transfers · ffc4ea79
      Alan Stern authored
      Part of the emulation performed by dummy-hcd is accounting for
      bandwidth utilization.  The total amount of data transferred in a
      single frame is supposed to be no larger than an actual USB connection
      could accommodate.
      
      Currently the driver performs bandwidth limiting only for bulk
      transfers; control and periodic transfers are effectively unlimited.
      (Presumably drivers were not expected to request extremely large
      control or interrupt transfers.)  This patch improves the situation
      somewhat by restricting them as well.
      
      The emulation still isn't perfect.  On a real system, even 0-length
      transfers use some bandwidth because of transaction overhead
      (IN, OUT, ACK, NACK packets) and packet overhead (SYNC, PID, bit
      stuffing, CRC, EOP).  Adding in those factors is left as an exercise
      for a later patch.
      Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: default avatarFelipe Balbi <felipe.balbi@linux.intel.com>
      ffc4ea79
  3. 09 Oct, 2017 1 commit
  4. 07 Oct, 2017 4 commits