From patchwork Mon May 31 13:15:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 450827 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=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 A31C9C47080 for ; Mon, 31 May 2021 14:59:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 82215610A0 for ; Mon, 31 May 2021 14:59:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234150AbhEaPBD (ORCPT ); Mon, 31 May 2021 11:01:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:51182 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234424AbhEaO7c (ORCPT ); Mon, 31 May 2021 10:59:32 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 352246193F; Mon, 31 May 2021 14:01:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1622469693; bh=WEChJ6jb79usMwhfXxnCXY+Floj+im3Lq2Q0hut9XTw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g2RmYMP8zYdTEhaTmKBPtv7d5lCGEzkR43c73GX4WmBkwk4/YeQKo3NAMEdY49V2H mjTn7xGco842FTysvl57d2aNQYrBmRYOXBjPFLqB//WfFpNBfnpVmxqYIWwdp4XF2v wp3XjLwxti7jilw11sFiiI6u3ueVllDN22RHhxC8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alan Stern , Chunfeng Yun Subject: [PATCH 5.12 296/296] usb: core: reduce power-on-good delay time of root hub Date: Mon, 31 May 2021 15:15:51 +0200 Message-Id: <20210531130713.653728152@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210531130703.762129381@linuxfoundation.org> References: <20210531130703.762129381@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 @@ -148,8 +148,10 @@ 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,