From patchwork Fri May 7 09:33:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Chiu X-Patchwork-Id: 432768 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, 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 C3015C433B4 for ; Fri, 7 May 2021 09:33:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9551A61460 for ; Fri, 7 May 2021 09:33:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236722AbhEGJeq (ORCPT ); Fri, 7 May 2021 05:34:46 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:39436 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236292AbhEGJeo (ORCPT ); Fri, 7 May 2021 05:34:44 -0400 Received: from 61-220-137-37.hinet-ip.hinet.net ([61.220.137.37] helo=localhost.localdomain) by youngberry.canonical.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1lewrd-0002Vw-VH; Fri, 07 May 2021 09:33:42 +0000 From: chris.chiu@canonical.com To: stern@rowland.harvard.edu, gregkh@linuxfoundation.org, m.v.b@runbox.com, hadess@hadess.net Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Chris Chiu Subject: [PATCH 1/2] USB: reset-resume the device when PORT_SUSPEND is set but timeout Date: Fri, 7 May 2021 17:33:28 +0800 Message-Id: <20210507093329.895-2-chris.chiu@canonical.com> X-Mailer: git-send-email 2.21.1 (Apple Git-122.3) In-Reply-To: <20210507093329.895-1-chris.chiu@canonical.com> References: <20210507093329.895-1-chris.chiu@canonical.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org From: Chris Chiu On the Realtek hub of Dell Dock WD19, the port which has wakeup enabled descendants will sometimes timeout when setting PORT_SUSPEND feature. After checking the PORT_SUSPEND bit in wPortStatus, it is already set. However, the hub will fail to activate because the PORT_SUSPEND feature of that port is not cleared during resume. All devices connecting via the port are lost after resume. This commit force reset-resume the device connected to the timeout but suspended port so that the hub will have chance to clear the PORT_SUSPEND feature during resume. Signed-off-by: Chris Chiu --- drivers/usb/core/hub.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index b2bc4b7c4289..18603949a8de 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3385,6 +3385,21 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg) status = 0; } if (status) { + if (status == -ETIMEDOUT) { + u16 portstatus, portchange; + + status = hub_port_status(hub, port1, &portstatus, + &portchange); + + dev_dbg(&port_dev->dev, + "suspend timeout, status %04x\n", portstatus); + + if (status == 0 && port_is_suspended(hub, portstatus)) { + udev->reset_resume = 1; + goto err_wakeup; + } + } + dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status); /* Try to enable USB3 LTM again */