xhci: handle some XHCI_TRUST_TX_LENGTH quirks cases as default behaviour.
authorMathias Nyman <mathias.nyman@linux.intel.com>
Wed, 11 Dec 2019 14:20:06 +0000 (16:20 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 11 Dec 2019 14:32:19 +0000 (15:32 +0100)
commit7ff11162808cc2ec66353fc012c58bb449c892c3
treed14cf83454e6f0112e639cef56bd47c9d1da5505
parent7c67cf6658cec70d8a43229f2ce74ca1443dc95e
xhci: handle some XHCI_TRUST_TX_LENGTH quirks cases as default behaviour.

xhci driver claims it needs XHCI_TRUST_TX_LENGTH quirk for both
Broadcom/Cavium and a Renesas xHC controllers.

The quirk was inteded for handling false "success" complete event for
transfers that had data left untransferred.
These transfers should complete with "short packet" events instead.

In these two new cases the false "success" completion is reported
after a "short packet" if the TD consists of several TRBs.
xHCI specs 4.10.1.1.2 say remaining TRBs should report "short packet"
as well after the first short packet in a TD, but this issue seems so
common it doesn't make sense to add the quirk for all vendors.

Turn these events into short packets automatically instead.

This gets rid of the  "The WARN Successful completion on short TX for
slot 1 ep 1: needs XHCI_TRUST_TX_LENGTH quirk" warning in many cases.

Cc: <stable@vger.kernel.org>
Reported-by: Eli Billauer <eli.billauer@gmail.com>
Reported-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Eli Billauer <eli.billauer@gmail.com>
Tested-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20191211142007.8847-6-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/xhci-ring.c