From patchwork Thu Apr 6 13:08:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ivan Bornyakov X-Patchwork-Id: 13203305 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88CBCC7618D for ; Thu, 6 Apr 2023 13:09:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237793AbjDFNJ2 (ORCPT ); Thu, 6 Apr 2023 09:09:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236370AbjDFNJY (ORCPT ); Thu, 6 Apr 2023 09:09:24 -0400 Received: from mail.pr-group.ru (mail.pr-group.ru [178.18.215.3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AF966191; Thu, 6 Apr 2023 06:09:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=metrotek.ru; s=mail; h=from:subject:date:message-id:to:cc:mime-version:content-transfer-encoding: in-reply-to:references; bh=IO1EPmwiDtC2Abwn+uXaFr8L4ym/D/q1VCAduJB0S5E=; b=OqltBQhyEToBbHc0pbG9rU+aQL2jXagCBFKlbuLlIaYcVVsw4bEx8zc+LE0uxjCLrcPAMLIuDxYZp fSKKeUcIZLVgPHaLJqHwANV4WmXeBt9im0Wifc4gm/IJyzsRHWVgsendPWpfDEt6220AB/fOnK+TQ6 CWqQ4w5Vw2agZ3COwJ2RORYCvF3d7pxQgz/juVenZrp3Q+7/6M2duggyILwr29Rm4SHvSCTan6TLF2 2VUV1h3zHMRq10Wae0ssb/1KV1zsxFo5EcAR/R+jK7tOG1nHJriXsvHSHTyFkvxKMWs8WmPmjUSYzI kSM8+WCK7G8iDy0inrrTzbqVF7iULVQ== X-Kerio-Anti-Spam: Build: [Engines: 2.17.2.1477, Stamp: 3], Multi: [Enabled, t: (0.000006,0.014053)], BW: [Enabled, t: (0.000028,0.000001)], RTDA: [Enabled, t: (0.103778), Hit: No, Details: v2.49.0; Id: 15.8wv4b.1gtbaumsr.6g4f; mclb], total: 0(700) X-Footer: bWV0cm90ZWsucnU= Received: from localhost.localdomain ([78.37.166.219]) (authenticated user i.bornyakov@metrotek.ru) by mail.pr-group.ru with ESMTPSA (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256 bits)); Thu, 6 Apr 2023 16:09:02 +0300 From: Ivan Bornyakov To: netdev@vger.kernel.org Cc: Ivan Bornyakov , linux@armlinux.org.uk, andrew@lunn.ch, hkallweit1@gmail.com, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, linux-kernel@vger.kernel.org, system@metrotek.ru, stable@vger.kernel.org Subject: [PATCH net v2 1/2] net: sfp: initialize sfp->i2c_block_size at sfp allocation Date: Thu, 6 Apr 2023 16:08:32 +0300 Message-Id: <20230406130833.32160-2-i.bornyakov@metrotek.ru> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230406130833.32160-1-i.bornyakov@metrotek.ru> References: <20230406130833.32160-1-i.bornyakov@metrotek.ru> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org sfp->i2c_block_size is initialized at SFP module insertion in sfp_sm_mod_probe(). Because of that, if SFP module was never inserted since boot, sfp_read() call will lead to zero-length I2C read attempt, and not all I2C controllers are happy with zero-length reads. One way to issue sfp_read() on empty SFP cage is to execute ethtool -m. If SFP module was never plugged since boot, there will be a zero-length I2C read attempt. # ethtool -m xge0 i2c i2c-3: adapter quirk: no zero length (addr 0x0050, size 0, read) Cannot get Module EEPROM data: Operation not supported If SFP module was plugged then removed at least once, sfp->i2c_block_size will be initialized and ethtool -m will fail with different exit code and without I2C error # ethtool -m xge0 Cannot get Module EEPROM data: Remote I/O error Fix this by initializing sfp->i2_block_size at struct sfp allocation stage so no wild sfp_read() could issue zero-length I2C read. Signed-off-by: Ivan Bornyakov Fixes: 0d035bed2a4a ("net: sfp: VSOL V2801F / CarlitoxxPro CPGOS03-0490 v2.0 workaround") Cc: stable@vger.kernel.org Reviewed-by: Andrew Lunn --- drivers/net/phy/sfp.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c index 40c9a64c5e30..5663a184644d 100644 --- a/drivers/net/phy/sfp.c +++ b/drivers/net/phy/sfp.c @@ -212,6 +212,12 @@ static const enum gpiod_flags gpio_flags[] = { #define SFP_PHY_ADDR 22 #define SFP_PHY_ADDR_ROLLBALL 17 +/* SFP_EEPROM_BLOCK_SIZE is the size of data chunk to read the EEPROM + * at a time. Some SFP modules and also some Linux I2C drivers do not like + * reads longer than 16 bytes. + */ +#define SFP_EEPROM_BLOCK_SIZE 16 + struct sff_data { unsigned int gpios; bool (*module_supported)(const struct sfp_eeprom_id *id); @@ -1928,11 +1934,7 @@ static int sfp_sm_mod_probe(struct sfp *sfp, bool report) u8 check; int ret; - /* Some SFP modules and also some Linux I2C drivers do not like reads - * longer than 16 bytes, so read the EEPROM in chunks of 16 bytes at - * a time. - */ - sfp->i2c_block_size = 16; + sfp->i2c_block_size = SFP_EEPROM_BLOCK_SIZE; ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base)); if (ret < 0) { @@ -2615,6 +2617,7 @@ static struct sfp *sfp_alloc(struct device *dev) return ERR_PTR(-ENOMEM); sfp->dev = dev; + sfp->i2c_block_size = SFP_EEPROM_BLOCK_SIZE; mutex_init(&sfp->sm_mutex); mutex_init(&sfp->st_mutex);