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=-19.1 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, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 5D67DC47083 for ; Mon, 31 May 2021 13:22:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 437E26142E for ; Mon, 31 May 2021 13:22:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232106AbhEaNYU (ORCPT ); Mon, 31 May 2021 09:24:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:55814 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231777AbhEaNTr (ORCPT ); Mon, 31 May 2021 09:19:47 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1A1D2613AF; Mon, 31 May 2021 13:18:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1622467086; bh=nErmVLyr1tlj/n+cc0pBDyAqBB0N06DTGmAaHj+iXNE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QR2y76CQxUk30szaSUFFZzyE55BQw0xaf7u36kEPN111vRrsF384BxAVNQoL5FV0v YiSzeQCDDBzhJNGHBSCvc6dmfYRkGPqPi2PK40bjj4lE0bRJN4Lu3RnDbqvmdekCAZ 1cz8PrHe7U04N2Pi3gj8lM/NgMN9yw14IIzhyV3g= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alan Stern , Chunfeng Yun Subject: [PATCH 4.4 54/54] usb: core: reduce power-on-good delay time of root hub Date: Mon, 31 May 2021 15:14:20 +0200 Message-Id: <20210531130636.756816902@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210531130635.070310929@linuxfoundation.org> References: <20210531130635.070310929@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: linux-kernel@vger.kernel.org From: Chunfeng Yun commit 90d28fb53d4a51299ff324dede015d5cb11b88a2 upstream. Return the exactly delay time given by root hub descriptor, this helps to reduce resume time etc. Due to the root hub descriptor is usually provided by the host controller driver, if there is compatibility for a root hub, we can fix it easily without affect other root hub Acked-by: Alan Stern Signed-off-by: Chunfeng Yun Link: https://lore.kernel.org/r/1618017645-12259-1-git-send-email-chunfeng.yun@mediatek.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/usb/core/hub.h +++ b/drivers/usb/core/hub.h @@ -140,8 +140,10 @@ static inline unsigned hub_power_on_good { unsigned delay = hub->descriptor->bPwrOn2PwrGood * 2; - /* Wait at least 100 msec for power to become stable */ - return max(delay, 100U); + if (!hub->hdev->parent) /* root hub */ + return delay; + else /* Wait at least 100 msec for power to become stable */ + return max(delay, 100U); } static inline int hub_port_debounce_be_connected(struct usb_hub *hub,