From patchwork Mon Mar 15 13:57:24 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 401403 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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 177DCC433E0 for ; Mon, 15 Mar 2021 14:03:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B9B7D64EF1 for ; Mon, 15 Mar 2021 14:03:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233496AbhCOOBw (ORCPT ); Mon, 15 Mar 2021 10:01:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:37582 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232785AbhCON74 (ORCPT ); Mon, 15 Mar 2021 09:59:56 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 9B6AC64EFD; Mon, 15 Mar 2021 13:59:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1615816776; bh=AneO6NVmCoHwv/zQGDAcWoadoYb/AGpFcxb2TvJ4kl4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TcIcVZ3sK5h4DOB6F+M/yvdAdxeufwJuVt2DY3u1RH+gUwMJyVHdccQ9at4OI7joJ NU2sWAHocntgak7GKT5Igkib9msgUMdbAvyWX47YiDcW3zv4cZWgGJAyGWWvhabKlz lvjcnDmv9dTSQra5CWTzLJTMin6fxWb18j9jasIk= From: gregkh@linuxfoundation.org To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mathias Nyman Subject: [PATCH 4.14 54/95] xhci: Improve detection of device initiated wake signal. Date: Mon, 15 Mar 2021 14:57:24 +0100 Message-Id: <20210315135742.045483785@linuxfoundation.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210315135740.245494252@linuxfoundation.org> References: <20210315135740.245494252@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Greg Kroah-Hartman From: Mathias Nyman commit 253f588c70f66184b1f3a9bbb428b49bbda73e80 upstream. A xHC USB 3 port might miss the first wake signal from a USB 3 device if the port LFPS reveiver isn't enabled fast enough after xHC resume. xHC host will anyway be resumed by a PME# signal, but will go back to suspend if no port activity is seen. The device resends the U3 LFPS wake signal after a 100ms delay, but by then host is already suspended, starting all over from the beginning of this issue. USB 3 specs say U3 wake LFPS signal is sent for max 10ms, then device needs to delay 100ms before resending the wake. Don't suspend immediately if port activity isn't detected in resume. Instead add a retry. If there is no port activity then delay for 120ms, and re-check for port activity. Cc: Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20210311115353.2137560-3-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -1021,6 +1021,7 @@ int xhci_resume(struct xhci_hcd *xhci, b struct usb_hcd *secondary_hcd; int retval = 0; bool comp_timer_running = false; + bool pending_portevent = false; if (!hcd->state) return 0; @@ -1154,13 +1155,22 @@ int xhci_resume(struct xhci_hcd *xhci, b done: if (retval == 0) { - /* Resume root hubs only when have pending events. */ - if (xhci_pending_portevent(xhci)) { + /* + * Resume roothubs only if there are pending events. + * USB 3 devices resend U3 LFPS wake after a 100ms delay if + * the first wake signalling failed, give it that chance. + */ + pending_portevent = xhci_pending_portevent(xhci); + if (!pending_portevent) { + msleep(120); + pending_portevent = xhci_pending_portevent(xhci); + } + + if (pending_portevent) { usb_hcd_resume_root_hub(xhci->shared_hcd); usb_hcd_resume_root_hub(hcd); } } - /* * If system is subject to the Quirk, Compliance Mode Timer needs to * be re-initialized Always after a system resume. Ports are subject