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 55547C433EF for ; Mon, 24 Jan 2022 20:11:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378979AbiAXUKJ (ORCPT ); Mon, 24 Jan 2022 15:10:09 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:55976 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359401AbiAXT7l (ORCPT ); Mon, 24 Jan 2022 14:59:41 -0500 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 dfw.source.kernel.org (Postfix) with ESMTPS id F1F4F60B89; Mon, 24 Jan 2022 19:59:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0EA32C340E5; Mon, 24 Jan 2022 19:59:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643054379; bh=gihdcPke+Avb3ww8X3kO4UJgUteet+I3HWKLaDdFe5E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wsb4Nmg0jd1cWko3wZ3czK43vtxeaUZI6pd6GETlcAfGqW+7XarFmyrOmkdrEtsPC DWn11nCgSp5sQe3KYTc+ANzi1zQbdWHBrT8sZ9DN95/foGjD4AnuDcLnpoxfK5DHMU ImOGgqM2851ZfcSvRKjsvqJ/SZHvFNzJivwHZN7Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alan Stern , Kai-Heng Feng , Sasha Levin Subject: [PATCH 5.10 371/563] usb: hub: Add delay for SuperSpeed hub resume to let links transit to U0 Date: Mon, 24 Jan 2022 19:42:16 +0100 Message-Id: <20220124184037.242998014@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124184024.407936072@linuxfoundation.org> References: <20220124184024.407936072@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Kai-Heng Feng [ Upstream commit 00558586382891540c59c9febc671062425a6e47 ] When a new USB device gets plugged to nested hubs, the affected hub, which connects to usb 2-1.4-port2, doesn't report there's any change, hence the nested hubs go back to runtime suspend like nothing happened: [ 281.032951] usb usb2: usb wakeup-resume [ 281.032959] usb usb2: usb auto-resume [ 281.032974] hub 2-0:1.0: hub_resume [ 281.033011] usb usb2-port1: status 0263 change 0000 [ 281.033077] hub 2-0:1.0: state 7 ports 4 chg 0000 evt 0000 [ 281.049797] usb 2-1: usb wakeup-resume [ 281.069800] usb 2-1: Waited 0ms for CONNECT [ 281.069810] usb 2-1: finish resume [ 281.070026] hub 2-1:1.0: hub_resume [ 281.070250] usb 2-1-port4: status 0203 change 0000 [ 281.070272] usb usb2-port1: resume, status 0 [ 281.070282] hub 2-1:1.0: state 7 ports 4 chg 0010 evt 0000 [ 281.089813] usb 2-1.4: usb wakeup-resume [ 281.109792] usb 2-1.4: Waited 0ms for CONNECT [ 281.109801] usb 2-1.4: finish resume [ 281.109991] hub 2-1.4:1.0: hub_resume [ 281.110147] usb 2-1.4-port2: status 0263 change 0000 [ 281.110234] usb 2-1-port4: resume, status 0 [ 281.110239] usb 2-1-port4: status 0203, change 0000, 10.0 Gb/s [ 281.110266] hub 2-1.4:1.0: state 7 ports 4 chg 0000 evt 0000 [ 281.110426] hub 2-1.4:1.0: hub_suspend [ 281.110565] usb 2-1.4: usb auto-suspend, wakeup 1 [ 281.130998] hub 2-1:1.0: hub_suspend [ 281.137788] usb 2-1: usb auto-suspend, wakeup 1 [ 281.142935] hub 2-0:1.0: state 7 ports 4 chg 0000 evt 0000 [ 281.177828] usb 2-1: usb wakeup-resume [ 281.197839] usb 2-1: Waited 0ms for CONNECT [ 281.197850] usb 2-1: finish resume [ 281.197984] hub 2-1:1.0: hub_resume [ 281.198203] usb 2-1-port4: status 0203 change 0000 [ 281.198228] usb usb2-port1: resume, status 0 [ 281.198237] hub 2-1:1.0: state 7 ports 4 chg 0010 evt 0000 [ 281.217835] usb 2-1.4: usb wakeup-resume [ 281.237834] usb 2-1.4: Waited 0ms for CONNECT [ 281.237845] usb 2-1.4: finish resume [ 281.237990] hub 2-1.4:1.0: hub_resume [ 281.238067] usb 2-1.4-port2: status 0263 change 0000 [ 281.238148] usb 2-1-port4: resume, status 0 [ 281.238152] usb 2-1-port4: status 0203, change 0000, 10.0 Gb/s [ 281.238166] hub 2-1.4:1.0: state 7 ports 4 chg 0000 evt 0000 [ 281.238385] hub 2-1.4:1.0: hub_suspend [ 281.238523] usb 2-1.4: usb auto-suspend, wakeup 1 [ 281.258076] hub 2-1:1.0: hub_suspend [ 281.265744] usb 2-1: usb auto-suspend, wakeup 1 [ 281.285976] hub 2-0:1.0: hub_suspend [ 281.285988] usb usb2: bus auto-suspend, wakeup 1 USB 3.2 spec, 9.2.5.4 "Changing Function Suspend State" says that "If the link is in a non-U0 state, then the device must transition the link to U0 prior to sending the remote wake message", but the hub only transits the link to U0 after signaling remote wakeup. So be more forgiving and use a 20ms delay to let the link transit to U0 for remote wakeup. Suggested-by: Alan Stern Acked-by: Alan Stern Signed-off-by: Kai-Heng Feng Link: https://lore.kernel.org/r/20211215120108.336597-1-kai.heng.feng@canonical.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/core/hub.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index af15dbe6bb141..18ee3914b4686 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -1109,7 +1109,10 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type) } else { hub_power_on(hub, true); } - } + /* Give some time on remote wakeup to let links to transit to U0 */ + } else if (hub_is_superspeed(hub->hdev)) + msleep(20); + init2: /* -- 2.34.1