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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 8BD32C43619 for ; Thu, 15 Apr 2021 15:15:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 662F3613B0 for ; Thu, 15 Apr 2021 15:15:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236483AbhDOPO7 (ORCPT ); Thu, 15 Apr 2021 11:14:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:48730 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234724AbhDOPEz (ORCPT ); Thu, 15 Apr 2021 11:04:55 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 72497613C7; Thu, 15 Apr 2021 14:58:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1618498724; bh=Wr0mAqzuayHfsB4hc1QbyERS7Jdho/MmBrqo3CX1o08=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WP9O4CgTjDkVeMd2phQ414oOg924Gj0aq0/EqP55bSCj8mbERHyhaA9L4OTdBlMJG DWIkqBaRNXvPEkeyi+gV5wAQmHV+3urjl2sVoOQQqx0t/zTVxwzlt0qcjxz1TVajA6 AInlLMMKuJUWitBJ8Zn6cePtxQsITeJ9CPWTq8Gk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Russell King , Andrew Lunn , Jakub Kicinski , =?UTF-8?q?Pali=20Roh=C3=A1r?= Subject: [PATCH 5.11 23/23] net: sfp: cope with SFPs that set both LOS normal and LOS inverted Date: Thu, 15 Apr 2021 16:48:30 +0200 Message-Id: <20210415144413.874583134@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210415144413.146131392@linuxfoundation.org> References: <20210415144413.146131392@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Russell King commit 624407d2cf14ff58e53bf4b2af9595c4f21d606e upstream. The SFP MSA defines two option bits in byte 65 to indicate how the Rx_LOS signal on SFP pin 8 behaves: bit 2 - Loss of Signal implemented, signal inverted from standard definition in SFP MSA (often called "Signal Detect"). bit 1 - Loss of Signal implemented, signal as defined in SFP MSA (often called "Rx_LOS"). Clearly, setting both bits results in a meaningless situation: it would mean that LOS is implemented in both the normal sense (1 = signal loss) and inverted sense (0 = signal loss). Unfortunately, there are modules out there which set both bits, which will be initially interpret as "inverted" sense, and then, if the LOS signal changes state, we will toggle between LINK_UP and WAIT_LOS states. Change our LOS handling to give well defined behaviour: only interpret these bits as meaningful if exactly one is set, otherwise treat it as if LOS is not implemented. Signed-off-by: Russell King Reviewed-by: Andrew Lunn Link: https://lore.kernel.org/r/E1kyYQa-0004iR-CU@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski Cc: Pali Rohár Signed-off-by: Greg Kroah-Hartman --- drivers/net/phy/sfp.c | 36 ++++++++++++++++++++++-------------- 1 file changed, 22 insertions(+), 14 deletions(-) --- a/drivers/net/phy/sfp.c +++ b/drivers/net/phy/sfp.c @@ -1501,15 +1501,19 @@ static void sfp_sm_link_down(struct sfp static void sfp_sm_link_check_los(struct sfp *sfp) { - unsigned int los = sfp->state & SFP_F_LOS; + const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED); + const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL); + __be16 los_options = sfp->id.ext.options & (los_inverted | los_normal); + bool los = false; /* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL - * are set, we assume that no LOS signal is available. + * are set, we assume that no LOS signal is available. If both are + * set, we assume LOS is not implemented (and is meaningless.) */ - if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED)) - los ^= SFP_F_LOS; - else if (!(sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL))) - los = 0; + if (los_options == los_inverted) + los = !(sfp->state & SFP_F_LOS); + else if (los_options == los_normal) + los = !!(sfp->state & SFP_F_LOS); if (los) sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0); @@ -1519,18 +1523,22 @@ static void sfp_sm_link_check_los(struct static bool sfp_los_event_active(struct sfp *sfp, unsigned int event) { - return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) && - event == SFP_E_LOS_LOW) || - (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) && - event == SFP_E_LOS_HIGH); + const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED); + const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL); + __be16 los_options = sfp->id.ext.options & (los_inverted | los_normal); + + return (los_options == los_inverted && event == SFP_E_LOS_LOW) || + (los_options == los_normal && event == SFP_E_LOS_HIGH); } static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event) { - return (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_INVERTED) && - event == SFP_E_LOS_HIGH) || - (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_LOS_NORMAL) && - event == SFP_E_LOS_LOW); + const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED); + const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL); + __be16 los_options = sfp->id.ext.options & (los_inverted | los_normal); + + return (los_options == los_inverted && event == SFP_E_LOS_HIGH) || + (los_options == los_normal && event == SFP_E_LOS_LOW); } static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)