Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753682AbcKNHmz (ORCPT ); Mon, 14 Nov 2016 02:42:55 -0500 Received: from mx07-00178001.pphosted.com ([62.209.51.94]:36209 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752739AbcKNHmy (ORCPT ); Mon, 14 Nov 2016 02:42:54 -0500 Subject: Re: [PATCH net] net: stmmac: Fix lack of link transition for fixed PHYs To: Florian Fainelli , References: <20161114015036.6926-1-f.fainelli@gmail.com> CC: , Alexandre Torgue , open list From: Giuseppe CAVALLARO Message-ID: Date: Mon, 14 Nov 2016 08:42:45 +0100 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0 MIME-Version: 1.0 In-Reply-To: <20161114015036.6926-1-f.fainelli@gmail.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.52.139.54] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-11-14_03:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2070 Lines: 50 On 11/14/2016 2:50 AM, Florian Fainelli wrote: > Commit 52f95bbfcf72 ("stmmac: fix adjust link call in case of a switch > is attached") added some logic to avoid polling the fixed PHY and > therefore invoking the adjust_link callback more than once, since this > is a fixed PHY and link events won't be generated. > > This works fine the first time, because we start with phydev->irq = > PHY_POLL, so we call adjust_link, then we set phydev->irq = > PHY_IGNORE_INTERRUPT and we stop polling the PHY. > > Now, if we called ndo_close(), which calls both phy_stop() and does an > explicit netif_carrier_off(), we end up with a link down. Upon calling > ndo_open() again, despite starting the PHY state machine, we have > PHY_IGNORE_INTERRUPT set, and we generate no link event at all, so the > link is permanently down. > > 52f95bbfcf72 ("stmmac: fix adjust link call in case of a switch is attached") > Signed-off-by: Florian Fainelli > --- > Alexandre, Peppe, > > The original patch is already a hack, but since this is a bugfix, I took the > same approach that you did here to backport this to -stable kernels. Acked-by: Giuseppe Cavallaro > > drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > index 10909c9c0033..03dbf8e89c4c 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > @@ -882,6 +882,13 @@ static int stmmac_init_phy(struct net_device *dev) > return -ENODEV; > } > > + /* stmmac_adjust_link will change this to PHY_IGNORE_INTERRUPT to avoid > + * subsequent PHY polling, make sure we force a link transition if > + * we have a UP/DOWN/UP transition > + */ > + if (phydev->is_pseudo_fixed_link) > + phydev->irq = PHY_POLL; > + > pr_debug("stmmac_init_phy: %s: attached to PHY (UID 0x%x)" > " Link = %d\n", dev->name, phydev->phy_id, phydev->link); > >