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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 5211CC04EB8 for ; Fri, 30 Nov 2018 06:38:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1EFD82146D for ; Fri, 30 Nov 2018 06:38:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1EFD82146D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=socionext.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726800AbeK3Rq7 (ORCPT ); Fri, 30 Nov 2018 12:46:59 -0500 Received: from mx.socionext.com ([202.248.49.38]:17043 "EHLO mx.socionext.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726456AbeK3Rq7 (ORCPT ); Fri, 30 Nov 2018 12:46:59 -0500 Received: from unknown (HELO iyokan-ex.css.socionext.com) ([172.31.9.54]) by mx.socionext.com with ESMTP; 30 Nov 2018 15:38:44 +0900 Received: from mail.mfilter.local (m-filter-2 [10.213.24.62]) by iyokan-ex.css.socionext.com (Postfix) with ESMTP id 2477E60062; Fri, 30 Nov 2018 15:38:44 +0900 (JST) Received: from 172.31.9.53 (172.31.9.53) by m-FILTER with ESMTP; Fri, 30 Nov 2018 15:38:44 +0900 Received: from yuzu.css.socionext.com (yuzu [172.31.8.45]) by iyokan.css.socionext.com (Postfix) with ESMTP id 95B7A40394; Fri, 30 Nov 2018 15:38:43 +0900 (JST) Received: from [127.0.0.1] (unknown [10.213.132.48]) by yuzu.css.socionext.com (Postfix) with ESMTP id 6EE55120455; Fri, 30 Nov 2018 15:38:43 +0900 (JST) Date: Fri, 30 Nov 2018 15:38:43 +0900 From: Kunihiko Hayashi To: Heiner Kallweit Subject: Re: [RFC PATCH net] net: phy: fix the issue that netif always links up after resuming Cc: Florian Fainelli , Andrew Lunn , "David S. Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <325a028e-ce95-1055-1b59-ed6120eeb229@gmail.com> References: <20181130133738.813D.4A936039@socionext.com> <325a028e-ce95-1055-1b59-ed6120eeb229@gmail.com> Message-Id: <20181130153842.31FF.4A936039@socionext.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.70 [ja] Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Heiner, On Fri, 30 Nov 2018 07:20:27 +0100 wrote: > On 30.11.2018 05:37, Kunihiko Hayashi wrote: > > Hi Heiner Florian, > > > > Thank you for your comments. > > > > On Thu, 29 Nov 2018 16:37:48 -0800 wrote: > > > >> > >> > >> On 11/29/2018 2:47 PM, Heiner Kallweit wrote: > >>> On 29.11.2018 09:12, Kunihiko Hayashi wrote: > >>>> Even though the link is down before entering hibernation, > >>>> there is an issue that the network interface always links up after resuming > >>>> from hibernation. > >>>> > >>>> The phydev->state is PHY_READY before enabling the network interface, so > >>>> the link is down. After resuming from hibernation, the phydev->state is > >>>> forcibly set to PHY_UP in mdio_bus_phy_restore(), and the link becomes up. > >>>> > >>>> This patch expects to solve the issue by changing phydev->state to PHY_UP > >>>> only when the link is up. > >>>> > >>>> Signed-off-by: Kunihiko Hayashi > >>>> --- > >>>> drivers/net/phy/phy_device.c | 6 ++++-- > >>>> 1 file changed, 4 insertions(+), 2 deletions(-) > >>>> > >>>> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c > >>>> index ab33d17..d5bba0f 100644 > >>>> --- a/drivers/net/phy/phy_device.c > >>>> +++ b/drivers/net/phy/phy_device.c > >>>> @@ -309,8 +309,10 @@ static int mdio_bus_phy_restore(struct device *dev) > >>>> return ret; > >>>> > >>>> /* The PHY needs to renegotiate. */ > >>>> - phydev->link = 0; > >>>> - phydev->state = PHY_UP; > >>>> + if (phydev->link) { > >>>> + phydev->link = 0; > >>>> + phydev->state = PHY_UP; > >>>> + } > >>>> > >>> Thanks for reporting. I agree that it isn't right to unconditionally set > >>> PHY_UP, because we don't know whether the PHY was started before > >>> hibernation. However I don't think using phydev->link as criteria is > >>> right. Example would be: PHY was started before hibernation, but w/o link. > >>> In this case we want to set PHY_UP to start an aneg, because a cable may > >>> have been plugged in whilst system was sleeping. > > > > Indeed. I didn't consider the case that the PHY was started but a cable was > > unplugged before hibernation. > > > >>> So I think, similar to phy_stop_machine, we should use state >= UP and > >>> state != HALTED as criteria, and also phy_start_machine() would need to > >>> be called only if this criteria is met. > >>> > >>> It may make sense to add a helper for checking whether PHY is in a > >>> started state (>=UP && !=HALTED), because we need this in more than > >>> one place. > >> > >> Agreed, that would make sense. > > > > I agree, too. > > I'll try this in v2 patch that changes the PHY state to PHY_UP and calls > > phy_start_machine(), only when the PHY was started before hibernation. > > If I understand correctly, it will be like that: > > > > phydev->link = 0; > Even this may go into the if clause. If PHY isn't started then > phydev->link should be 0 anyway. Yes. To clarify more, this will go into the if clause. > > > if (phy_is_started(phydev)) { > > phydev->state = PHY_UP; > > phy_start_machine(phydev); > > } > > > Yes, this is what was meant. Thanks. Thank you, --- Best Regards, Kunihiko Hayashi