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=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 86985C433DB for ; Wed, 30 Dec 2020 16:11:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 594F520758 for ; Wed, 30 Dec 2020 16:11:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726586AbgL3QLZ (ORCPT ); Wed, 30 Dec 2020 11:11:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40776 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726277AbgL3QLY (ORCPT ); Wed, 30 Dec 2020 11:11:24 -0500 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6E3FC061799; Wed, 30 Dec 2020 08:10:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=iovC8r4bnQk0np2B6m8BqWWmAyM+9fqR5oThYphK294=; b=YNqW+iWGVeDNOkwHR5OS0ZNTn MtpsyTqDi2hI5Gl/BmqFrcwyZ4b2oucdId/fWmM5Afp/7X6QWB4o0IN5S97jnvQstJLXAhVPF1AGp XJknmguDAvn/8NOY6xhoUYlxJdRJtBEpF+l37p3w3IhH63g5cQQ/AY65IXKYE8EzgO9xRaFxOTgaS BlebZLqRYLNEiSLpXUxbcgqjECySZddH7CSJTiWZfNxMiYCbHKKQJ/znLnUFQONJg4VBdFA3wZaE3 KVqV5mV8uXZEh6KmYgjP5+cIYOfqYM+1hpxx3R8EvU0W7P+jUo/BlUA/NhW79AocQxu5OQY6+8a9j 3cXzEv4Wg==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:44912) by pandora.armlinux.org.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1kue3a-0005oN-AK; Wed, 30 Dec 2020 16:10:38 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.92) (envelope-from ) id 1kue3Z-0002KG-5T; Wed, 30 Dec 2020 16:10:37 +0000 Date: Wed, 30 Dec 2020 16:10:37 +0000 From: Russell King - ARM Linux admin To: Pali =?iso-8859-1?Q?Roh=E1r?= Cc: Andrew Lunn , Heiner Kallweit , "David S. Miller" , Jakub Kicinski , Marek =?iso-8859-1?Q?Beh=FAn?= , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/4] net: sfp: add workaround for Realtek RTL8672 and RTL9601C chips Message-ID: <20201230161036.GR1551@shell.armlinux.org.uk> References: <20201230154755.14746-1-pali@kernel.org> <20201230154755.14746-2-pali@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20201230154755.14746-2-pali@kernel.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: Russell King - ARM Linux admin Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 30, 2020 at 04:47:52PM +0100, Pali Rohár wrote: > Workaround for GPON SFP modules based on VSOL V2801F brand was added in > commit 0d035bed2a4a ("net: sfp: VSOL V2801F / CarlitoxxPro CPGOS03-0490 > v2.0 workaround"). But it works only for ids explicitly added to the list. > As there are more rebraded VSOL V2801F modules and OEM vendors are putting > into vendor name random strings we cannot build workaround based on ids. > > Moreover issue which that commit tried to workaround is generic not only to > VSOL based modules, but rather to all GPON modules based on Realtek RTL8672 > and RTL9601C chips. > > They can be found for example in following GPON modules: > * V-SOL V2801F > * C-Data FD511GX-RM0 > * OPTON GP801R > * BAUDCOM BD-1234-SFM > * CPGOS03-0490 v2.0 > * Ubiquiti U-Fiber Instant > * EXOT EGS1 > > Those Realtek chips have broken EEPROM emulator which for N-byte read > operation returns just one byte of EEPROM data followed by N-1 zeros. > > So introduce a new function sfp_id_needs_byte_io() which detects SFP > modules with these Realtek chips which have broken EEPROM emulator based on > N-1 zeros and switch to 1 byte EEPROM reading operation which workaround > this issue. > > This patch fixes reading EEPROM content from SFP modules based on Realtek > RTL8672 and RTL9601C chips. > > Fixes: 0d035bed2a4a ("net: sfp: VSOL V2801F / CarlitoxxPro CPGOS03-0490 v2.0 workaround") > Co-developed-by: Russell King > Signed-off-by: Russell King > Signed-off-by: Pali Rohár > --- > drivers/net/phy/sfp.c | 78 ++++++++++++++++++++++++------------------- > 1 file changed, 44 insertions(+), 34 deletions(-) > > diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c > index 91d74c1a920a..490e78a72dd6 100644 > --- a/drivers/net/phy/sfp.c > +++ b/drivers/net/phy/sfp.c > @@ -336,19 +336,11 @@ static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf, > size_t len) > { > struct i2c_msg msgs[2]; > - size_t block_size; > + u8 bus_addr = a2 ? 0x51 : 0x50; > + size_t block_size = sfp->i2c_block_size; > size_t this_len; > - u8 bus_addr; > int ret; > > - if (a2) { > - block_size = 16; > - bus_addr = 0x51; > - } else { > - block_size = sfp->i2c_block_size; > - bus_addr = 0x50; > - } > - NAK. You are undoing something that is definitely needed. The diagnostics must be read with sequential reads to be able to properly read the 16-bit values. The rest of the patch is fine; it's a shame the entire thing has been spoilt by this extra addition that was not in the patch we had been discussing off-list. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!