• Sarah Sharp's avatar
    xhci: USB 3.0 BW checking. · 2b698999
    Sarah Sharp authored
    The Intel Panther Point xHCI host tracks SuperSpeed endpoints in a
    different way than USB 2.0/1.1 endpoints.  The bandwidth interval tables
    are not used, and instead the bandwidth is calculated in a very simple
    way.  Bandwidth for SuperSpeed endpoints is tracked individually in each
    direction, since each direction has the full USB 3.0 bandwidth available.
    10% of the bus bandwidth is reserved for non-periodic transfers.
    
    This checking would be more complex if we had USB 3.0 LPM enabled, because
    an additional latency for isochronous ping times need to be taken into
    account.  However, we don't have USB 3.0 LPM support in Linux yet.
    Signed-off-by: default avatarSarah Sharp <sarah.a.sharp@linux.intel.com>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
    2b698999
xhci.c 113 KB