From patchwork Wed Aug 18 03:38:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Saravana Kannan X-Patchwork-Id: 499615 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, 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,USER_IN_DEF_DKIM_WL 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 BBA25C4338F for ; Wed, 18 Aug 2021 03:38:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D9F9610A6 for ; Wed, 18 Aug 2021 03:38:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237565AbhHRDjA (ORCPT ); Tue, 17 Aug 2021 23:39:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38934 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236340AbhHRDiu (ORCPT ); Tue, 17 Aug 2021 23:38:50 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 75CB3C061764 for ; Tue, 17 Aug 2021 20:38:16 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id e75-20020a25374e000000b00597165a06d2so1466949yba.6 for ; Tue, 17 Aug 2021 20:38:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=BEMUdr8X5Q4aL9TA7J3U2xLBZtVMZHuyJZqksg9L6+U=; b=r2ib7ss7DFluFVBCuF5BLjvbhbDWTq5l01Sq9U6fA1uYR58uS2GdlH2s1USJ0itLLy LhtOVKy1r0bSe17mRG2AaJAzPB791fm9h6RjVsAsk1js9r3FoNJdGDd8e57gQ6sEmJmt zuurs+QgmXUfg6mOh2VgEW7AyFTdsM5flBkvCDoFdMH1Jf0PGzzIBLmzMPAfUr85X8LY yVPRCD7kU/owvuh4W/8l47WHSqkQVmTmty+YifgSE73AKuAteEgwL3alhVhX53pHYneA N1NldWWx9K7B4h8k/n9aAW5TUXONi1KtK40+aZaYgIZeq3JjY7IZFyTVucChKUCpaCUI eSoA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=BEMUdr8X5Q4aL9TA7J3U2xLBZtVMZHuyJZqksg9L6+U=; b=YOCRSbu4/NC8JA5u/DLfZfA9LSG1xyuzLB/5kDA/xLLF//UM/znM4O7cCR6kocdMO7 WY3fjfXdhXYViKhI+cSMkkYeEhK6SvsnSqNS4ePnrNXYmZ7nDUt8Jmk/JoZPQzo4JLr/ lBiizLf5JHIy4n++jmqEWMBLkgOnojVnYblD5MO7JjLb2JgR6/B5Dt1hwTxbDwvRe66y eSPqAXAcNO2V1U7ILDgnuvjJK43HnRBMJSui7wvVQMoGkT1/UQva4Y1OrvZuxtR62+3D Szor7V+67aTtXRygxPzd/t9f2N9weftFdxVOGtVAx3hulrEgbHAICF2gG+AhowUNvYmJ WFEA== X-Gm-Message-State: AOAM533bFqzysiv9EB3qW3vxfz2pqxDzEbHahkSqkvDZRH+Qq0bGdUGw v8urxLj3suCZL1Ghlwk69S40ne8WihKUtYg= X-Google-Smtp-Source: ABdhPJy5LvWk3456EERDnC1tvN03sDdUbOu+LZxfyycl1yfSMIZ6x9KrYprNC1/bZPlkGy9r+vXkKJR0ze2Tbbg= X-Received: from saravanak.san.corp.google.com ([2620:15c:2d:3:7750:a56d:5272:72cb]) (user=saravanak job=sendgmr) by 2002:a25:8445:: with SMTP id r5mr9205574ybm.20.1629257895746; Tue, 17 Aug 2021 20:38:15 -0700 (PDT) Date: Tue, 17 Aug 2021 20:38:03 -0700 In-Reply-To: <20210818033804.3281057-1-saravanak@google.com> Message-Id: <20210818033804.3281057-4-saravanak@google.com> Mime-Version: 1.0 References: <20210818033804.3281057-1-saravanak@google.com> X-Mailer: git-send-email 2.33.0.rc1.237.g0d66db33f3-goog Subject: [PATCH net v3 3/3] net: mdio-mux: Handle -EPROBE_DEFER correctly From: Saravana Kannan To: Andrew Lunn , Heiner Kallweit , Russell King , "David S. Miller" , Jakub Kicinski , Jon Mason , David Daney Cc: Saravana Kannan , Marc Zyngier , Neil Armstrong , Kevin Hilman , kernel-team@android.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org When registering mdiobus children, if we get an -EPROBE_DEFER, we shouldn't ignore it and continue registering the rest of the mdiobus children. This would permanently prevent the deferring child mdiobus from working instead of reattempting it in the future. So, if a child mdiobus needs to be reattempted in the future, defer the entire mdio-mux initialization. This fixes the issue where PHYs sitting under the mdio-mux aren't initialized correctly if the PHY's interrupt controller is not yet ready when the mdio-mux is being probed. Additional context in the link below. Fixes: 0ca2997d1452 ("netdev/of/phy: Add MDIO bus multiplexer support.") Link: https://lore.kernel.org/lkml/CAGETcx95kHrv8wA-O+-JtfH7H9biJEGJtijuPVN0V5dUKUAB3A@mail.gmail.com/#t Signed-off-by: Saravana Kannan Reviewed-by: Andrew Lunn Acked-by: Marc Zyngier Tested-by: Marc Zyngier Acked-by: Kevin Hilman Tested-by: Kevin Hilman --- drivers/net/mdio/mdio-mux.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/mdio/mdio-mux.c b/drivers/net/mdio/mdio-mux.c index 13035e2685c4..ebd001f0eece 100644 --- a/drivers/net/mdio/mdio-mux.c +++ b/drivers/net/mdio/mdio-mux.c @@ -175,11 +175,15 @@ int mdio_mux_init(struct device *dev, cb->mii_bus->write = mdio_mux_write; r = of_mdiobus_register(cb->mii_bus, child_bus_node); if (r) { + mdiobus_free(cb->mii_bus); + if (r == -EPROBE_DEFER) { + ret_val = r; + goto err_loop; + } + devm_kfree(dev, cb); dev_err(dev, "Error: Failed to register MDIO bus for child %pOF\n", child_bus_node); - mdiobus_free(cb->mii_bus); - devm_kfree(dev, cb); } else { cb->next = pb->children; pb->children = cb;