From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 417A7C4CECE for ; Mon, 14 Oct 2019 08:04:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 212662054F for ; Mon, 14 Oct 2019 08:04:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730174AbfJNIEi (ORCPT ); Mon, 14 Oct 2019 04:04:38 -0400 Received: from mga12.intel.com ([192.55.52.136]:33045 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725934AbfJNIEi (ORCPT ); Mon, 14 Oct 2019 04:04:38 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 Oct 2019 01:04:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,295,1566889200"; d="scan'208";a="220032491" Received: from mattu-haswell.fi.intel.com (HELO [10.237.72.170]) ([10.237.72.170]) by fmsmga004.fm.intel.com with ESMTP; 14 Oct 2019 01:04:37 -0700 Subject: Re: [PATCH] xhci: Don't use soft retry if slot id > 0 To: Bernhard Gebetsberger Cc: Mathias Nyman , Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org References: <20191013003313.3497-1-bernhard.gebetsberger@gmx.at> From: Mathias Nyman Message-ID: <84476602-7551-b667-9803-55016e477b02@linux.intel.com> Date: Mon, 14 Oct 2019 11:06:40 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20191013003313.3497-1-bernhard.gebetsberger@gmx.at> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 13.10.2019 3.33, Bernhard Gebetsberger wrote: > According to the xhci specification(chapter 4.6.8.1) soft retry > shouldn't be used if the slot id is higher than 0. Currently some usb > devices break on some systems because soft retry is being used when > there is a transaction error, without checking the slot id. > That is not correct Specs say that soft retry should not be used if we are dealing with a FS/LS device behind a HS hub, this can be checked from the "TT Hub Slot ID" field in the slot context, which we do. In xhci all devices have a slot id, so this change would prevent soft retry almost completely. Specs 4.6.8.1: "Soft Retry attempts shall not be performed if the device is behind a TT in a HS Hub (i.e. TT Hub Slot ID > ‘0’)." -Mathias