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  1. 14 5月, 2011 1 次提交
    • S
      xhci: Fix full speed bInterval encoding. · b513d447
      由 Sarah Sharp 提交于 
      Dmitry's patch

dfa49c4a USB: xhci - fix math in xhci_get_endpoint_interval()

introduced a bug.  The USB 2.0 spec says that full speed isochronous endpoints'
bInterval must be decoded as an exponent to a power of two (e.g. interval =
2^(bInterval - 1)).  Full speed interrupt endpoints, on the other hand, don't
use exponents, and the interval in frames is encoded straight into bInterval.

Dmitry's patch was supposed to fix up the full speed isochronous to parse
bInterval as an exponent, but instead it changed the *interrupt* endpoint
bInterval decoding.  The isochronous endpoint encoding was the same.

This caused full speed devices with interrupt endpoints (including mice, hubs,
and USB to ethernet devices) to fail under NEC 0.96 xHCI host controllers:

[  100.909818] xhci_hcd 0000:06:00.0: add ep 0x83, slot id 1, new drop flags = 0x0, new add flags = 0x99, new slot info = 0x38100000
[  100.909821] xhci_hcd 0000:06:00.0: xhci_check_bandwidth called for udev ffff88011f0ea000
...
[  100.910187] xhci_hcd 0000:06:00.0: ERROR: unexpected command completion code 0x11.
[  100.910190] xhci_hcd 0000:06:00.0: xhci_reset_bandwidth called for udev ffff88011f0ea000

When the interrupt endpoint was added and a Configure Endpoint command was
issued to the host, the host controller would return a very odd error message
(0x11 means "Slot Not Enabled", which isn't true because the slot was enabled).
Probably the host controller was getting very confused with the bad encoding.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Dmitry Torokhov <dtor@vmware.com>
Reported-by: NThomas Lindroth <thomas.lindroth@gmail.com>
Tested-by: NThomas Lindroth <thomas.lindroth@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      b513d447
  3. 13 5月, 2011 3 次提交
  5. 12 5月, 2011 1 次提交
    • S
      xhci: Fix bug in control transfer cancellation. · 3abeca99
      由 Sarah Sharp 提交于 
      When the xHCI driver attempts to cancel a transfer, it issues a Stop
Endpoint command and waits for the host controller to indicate which TRB
it was in the middle of processing.  The host will put an event TRB with
completion code COMP_STOP on the event ring if it stops on a control
transfer TRB (or other types of transfer TRBs).  The ring handling code
is supposed to set ep->stopped_trb to the TRB that the host stopped on
when this happens.

Unfortunately, there is a long-standing bug in the control transfer
completion code.  It doesn't actually check to see if COMP_STOP is set
before attempting to process the transfer based on which part of the
control TD completed.  So when we get an event on the data phase of the
control TRB with COMP_STOP set, it thinks it's a normal completion of
the transfer and doesn't set ep->stopped_td or ep->stopped_trb.

When the ring handling code goes on to process the completion of the Stop
Endpoint command, it sees that ep->stopped_trb is not a part of the TD
it's trying to cancel.  It thinks the hardware has its enqueue pointer
somewhere further up in the ring, and thinks it's safe to turn the control
TRBs into no-op TRBs.  Since the hardware was in the middle of the control
TRBs to be cancelled, the proper software behavior is to issue a Set TR
dequeue pointer command.

It turns out that the NEC host controllers can handle active TRBs being
set to no-op TRBs after a stop endpoint command, but other host
controllers have issues with this out-of-spec software behavior.  Fix this
behavior.

This patch should be backported to kernels as far back as 2.6.31, but it
may be a bit challenging, since process_ctrl_td() was introduced in some
refactoring done in 2.6.36, and some endian-safe patches added in 2.6.40
that touch the same lines.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: stable@kernel.org
      3abeca99
  7. 11 5月, 2011 1 次提交
  9. 10 5月, 2011 6 次提交
  11. 07 5月, 2011 10 次提交
  13. 04 5月, 2011 6 次提交
  15. 03 5月, 2011 12 次提交