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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 531DBC433EF for ; Wed, 29 Dec 2021 08:30:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234860AbhL2Ia2 (ORCPT ); Wed, 29 Dec 2021 03:30:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40036 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234001AbhL2Ia1 (ORCPT ); Wed, 29 Dec 2021 03:30:27 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2DD39C061574; Wed, 29 Dec 2021 00:30:27 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 62C50B817F2; Wed, 29 Dec 2021 08:30:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 57DDBC36AE9; Wed, 29 Dec 2021 08:30:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1640766624; bh=YfRWdmIFWVyKrJ7vFVvxDn23niord7mBjwi8ie1DWCw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=2su2cXgwvAgNdVy/xvyHT6lpWj4Wv8Nu3cHDTcI1iknuBwxlDytrvPi4CLtoB2sBw c/L855RTGIOroiEwXQCj2coZAgWQpKYmsKfX/yfITuaJw3W/sZZSZe8FFU+POJPrF9 Ud9GeQgmuUKpyezUkEc5kDZApPdKHkd5Spkaw9IY= Date: Wed, 29 Dec 2021 09:30:14 +0100 From: Greg KH To: Puma Hsu Cc: mathias.nyman@intel.com, Albert Wang , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] xhci: re-initialize the HC during resume if HCE was set Message-ID: References: <20211228060246.2958070-1-pumahsu@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org A: http://en.wikipedia.org/wiki/Top_post Q: Were do I find info about this thing called top-posting? A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail? A: No. Q: Should I include quotations after my reply? http://daringfireball.net/2007/07/on_top On Wed, Dec 29, 2021 at 01:53:04PM +0800, Puma Hsu wrote: > This commit is not used to fix a specific commit. We find a condition > that when XHCI runs the resume process but the HCE flag is set, then > the Run/Stop bit of USBCMD cannot be set so that HC would not be > enabled. In fact, HC may already meet a problem at this moment. > Besides, in xHCI requirements specification revision 1.2, Table 5-21 > BIT(12) claims that Software should re-initialize the xHC when HCE is > set. Therefore, I think this commit could be the error handling for > HCE. So this does not actually fix an issue that you have seen in any device or testing? So it is not relevant for older kernels but just "nice to have"? How did you test this if you can not duplicate the problem? thanks, greg k-h