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>
Tue, 17 Dec 2019 19:07:04 +0000 (20:07 +0100)
commite03582344d00d7be9d24fbfeef8e4e74dce7401c
tree45171826f6d8455de48035165203b4fe0e754822
parentc9382a9ac1db15cd9c507e34c16177be1f3d2376
xhci: handle some XHCI_TRUST_TX_LENGTH quirks cases as default behaviour.

commit 7ff11162808cc2ec66353fc012c58bb449c892c3 upstream.

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