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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,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 AC8AEC433E9 for ; Fri, 22 Jan 2021 18:38:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 80CB023ABA for ; Fri, 22 Jan 2021 18:38:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728596AbhAVSiV (ORCPT ); Fri, 22 Jan 2021 13:38:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50086 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728457AbhAVOUs (ORCPT ); Fri, 22 Jan 2021 09:20:48 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 880D3C0613D6 for ; Fri, 22 Jan 2021 06:19:53 -0800 (PST) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1l2xHw-0005nm-AN; Fri, 22 Jan 2021 15:19:48 +0100 Received: from hardanger.blackshift.org (unknown [IPv6:2a03:f580:87bc:d400:aed1:e241:8b32:9cc0]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) (Authenticated sender: mkl-all@blackshift.org) by smtp.blackshift.org (Postfix) with ESMTPSA id 144315CA9B9; Fri, 22 Jan 2021 14:19:47 +0000 (UTC) Date: Fri, 22 Jan 2021 15:19:46 +0100 From: Marc Kleine-Budde To: Woojung.Huh@microchip.com Cc: netdev@vger.kernel.org, UNGLinuxDriver@microchip.com, kernel@pengutronix.de Subject: Re: [PATCH 2/2 net] lan78xx: workaround of forced 100 Full/Half duplex mode error Message-ID: <20210122141946.3bta67avfu4xmuv4@hardanger.blackshift.org> References: <9235D6609DB808459E95D78E17F2E43D408987FF@CHN-SV-EXMX02.mchp-main.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="npbz4kmb2deypzhb" Content-Disposition: inline In-Reply-To: <9235D6609DB808459E95D78E17F2E43D408987FF@CHN-SV-EXMX02.mchp-main.com> X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: netdev@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org --npbz4kmb2deypzhb Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Apr 25, 2016 at 10:22:36PM +0000, Woojung.Huh@microchip.com wrote: > From: Woojung Huh >=20 > At forced 100 Full & Half duplex mode, chip may fail to set mode correctly > when cable is switched between long(~50+m) and short one. > As workaround, set to 10 before setting to 100 at forced 100 F/H mode. Sorry to picking up this old patch. We're using a LAN7801T, with an external TI dp83tc811 PHY... > Signed-off-by: Woojung Huh > --- > drivers/net/usb/lan78xx.c | 29 ++++++++++++++++++++++++++++- > 1 file changed, 28 insertions(+), 1 deletion(-) >=20 > diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c > index 0460b81..f64778a 100644 > --- a/drivers/net/usb/lan78xx.c > +++ b/drivers/net/usb/lan78xx.c > @@ -1804,7 +1804,34 @@ static void lan78xx_remove_mdio(struct lan78xx_net= *dev) > =20 > static void lan78xx_link_status_change(struct net_device *net) > { > - /* nothing to do */ > + struct phy_device *phydev =3D net->phydev; > + int ret, temp; > + > + /* At forced 100 F/H mode, chip may fail to set mode correctly > + * when cable is switched between long(~50+m) and short one. > + * As workaround, set to 10 before setting to 100 > + * at forced 100 F/H mode. > + */ > + if (!phydev->autoneg && (phydev->speed =3D=3D 100)) { > + /* disable phy interrupt */ > + temp =3D phy_read(phydev, LAN88XX_INT_MASK); > + temp &=3D ~LAN88XX_INT_MASK_MDINTPIN_EN_; > + ret =3D phy_write(phydev, LAN88XX_INT_MASK, temp); It seems here you are assuming a microchip PHY attached, where the INT_MASK register is at 0x19. In think 0x19 is a reserved register. You better not write to it. Are there some microchips components where the MAC and the PHY are in one chip? Is that combination identifiable by the USB-ID? > + temp =3D phy_read(phydev, MII_BMCR); > + temp &=3D ~(BMCR_SPEED100 | BMCR_SPEED1000); > + phy_write(phydev, MII_BMCR, temp); /* set to 10 first */ > + temp |=3D BMCR_SPEED100; > + phy_write(phydev, MII_BMCR, temp); /* set to 100 later */ > + > + /* clear pending interrupt generated while workaround */ > + temp =3D phy_read(phydev, LAN88XX_INT_STS); > + > + /* enable phy interrupt back */ > + temp =3D phy_read(phydev, LAN88XX_INT_MASK); > + temp |=3D LAN88XX_INT_MASK_MDINTPIN_EN_; > + ret =3D phy_write(phydev, LAN88XX_INT_MASK, temp); > + } > } regards, Marc --=20 Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | --npbz4kmb2deypzhb Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEK3kIWJt9yTYMP3ehqclaivrt76kFAmAK3v8ACgkQqclaivrt 76m8jAf+MohCdWf8Nzf7n4bW2BaXBruIzmrenw6Esx/7tWjZpAs19yczWsDk+o9g L3bTGa4sEXY1DtAnM8UaRzeQyuqcJtw3u4kmhGY+ow7C2uEvwvkzoPTOCoroUgyD 7IuknHX65B2LxlC/GVMFXWkyddIAcvto5hHeyhA5DWGwF1IUnHTYFuG4RM+aMUC+ f35b31IbzHx7ccGnOoiJNX2kVHB5yDComye1ifq/gmDbyFwlUkzw8JC+sRNzb62m J8tvAYGw0TE69Qy4tmBrTBrw7uWXQsViE+UC95sf2DyLqngusft73ufhoIkpE4kO Md7T2m/CQpSVASLpb1U8tey/TO8ugQ== =0h0k -----END PGP SIGNATURE----- --npbz4kmb2deypzhb--