From patchwork Wed Dec 20 04:52:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luiz Angelo Daros de Luca X-Patchwork-Id: 13499508 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-pl1-f182.google.com (mail-pl1-f182.google.com [209.85.214.182]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 38FAAC2C3; Wed, 20 Dec 2023 04:53:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="U1yXN7tr" Received: by mail-pl1-f182.google.com with SMTP id d9443c01a7336-1d3ec3db764so1714905ad.2; Tue, 19 Dec 2023 20:53:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1703048006; x=1703652806; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=oCdzME/wc/7u1TobMBsXQV40LzKB+51jmYS/oXHHLXc=; b=U1yXN7trYxo5D5Cxn2wMtvdgBW3I5iibYfDFs+EFVSw5RrbfgW0V2JnepSR/eknnuU EpsL1gq9zU6faocDbEF/Ti5rt/BJZ6sCf9LKtG6rp+EtS/AXtm154DOsdw1KiJGz/8+Q 90xmBL1sHW2UxzNBmw3aYdpGUwgpof+FhbTMA/Fl+6aZVcqpgnRmy0MKJIgc5xP97YJy F1wF+OcWP3zrw+0a0dThfuDTzdTIACAlYBAzUuGY2hZu+AvFIkVRkEnYjU9TMWyxGUmW k1MbWzy4dpmD0LefHPRdQvz5G56rv0fzHrQSKfEr2fLUcwx+zoBHRPiuohAygutq9bhC Nq5Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1703048006; x=1703652806; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=oCdzME/wc/7u1TobMBsXQV40LzKB+51jmYS/oXHHLXc=; b=rE5XCdMQRrA3mriUyyQ+b2wzaQK1WiBM2T0NBYltjj3Z5GidlMHsjofugLiTpWnkM/ xgVKCwzyFXOgb6yYWrKEz9LPv43NDWG2emKDWMxj2ZsmyX4UBjq/piVFuho4XkI6+dNK cVvNbI5Xjb3NZpTonZ6QdPhqz/4MygRSNih8eYQVpwgAacpkTOYEgB2io7akENIKfbuY G/Is3ERQEP8KcC+x2DNaHQhgI/bhzcQrBdWpOGnGtCTFcxAZdYDoqKXAN+xpDfet5aeZ h4ebF38e6FMGTD3rLE444TNrJOHQEqKJx/0dVZtQba80iHEtAtFg4Ac7ga5I3n9sLA1E rLEA== X-Gm-Message-State: AOJu0YwmqkWB0eNs26ofu06VAp536AlnUby5Arj7eERb6aYSvKIk4thQ hFwqaAQT0BOK5nMhzSSkqCctq/ZqFT+DPimB X-Google-Smtp-Source: AGHT+IF3u/O7Dv8UZexVlCWkA9GaEQFhA0ieTFtwHTi+OR/olqfkZ7X0BSr1dk7b18xZlKq863OlDg== X-Received: by 2002:a17:902:a58b:b0:1d0:8d57:482 with SMTP id az11-20020a170902a58b00b001d08d570482mr9234611plb.50.1703048006398; Tue, 19 Dec 2023 20:53:26 -0800 (PST) Received: from tresc054937.tre-sc.gov.br ([187.94.103.218]) by smtp.gmail.com with ESMTPSA id u7-20020a170902b28700b001cfcd2fb7b0sm3049318plr.285.2023.12.19.20.53.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 Dec 2023 20:53:25 -0800 (PST) From: Luiz Angelo Daros de Luca To: netdev@vger.kernel.org Cc: andrew@lunn.ch, hkallweit1@gmail.com, linux@armlinux.org.uk, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, linux-kernel@vger.kernel.org, Luiz Angelo Daros de Luca Subject: [PATCH net-next] net: mdio: get/put device node during (un)registration Date: Wed, 20 Dec 2023 01:52:29 -0300 Message-ID: <20231220045228.27079-2-luizluca@gmail.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org The __of_mdiobus_register() function was storing the device node in dev.of_node without increasing its reference count. It implicitly relied on the caller to maintain the allocated node until the mdiobus was unregistered. Now, __of_mdiobus_register() will acquire the node before assigning it, and of_mdiobus_unregister_callback() will be called at the end of mdio_unregister(). Drivers can now release the node immediately after MDIO registration. Some of them are already doing that even before this patch. Signed-off-by: Luiz Angelo Daros de Luca --- drivers/net/mdio/of_mdio.c | 12 +++++++++++- drivers/net/phy/mdio_bus.c | 3 +++ include/linux/phy.h | 3 +++ 3 files changed, 17 insertions(+), 1 deletion(-) diff --git a/drivers/net/mdio/of_mdio.c b/drivers/net/mdio/of_mdio.c index 64ebcb6d235c..9b6cab6154e0 100644 --- a/drivers/net/mdio/of_mdio.c +++ b/drivers/net/mdio/of_mdio.c @@ -139,6 +139,11 @@ bool of_mdiobus_child_is_phy(struct device_node *child) } EXPORT_SYMBOL(of_mdiobus_child_is_phy); +static void __of_mdiobus_unregister_callback(struct mii_bus *mdio) +{ + of_node_put(mdio->dev.of_node); +} + /** * __of_mdiobus_register - Register mii_bus and create PHYs from the device tree * @mdio: pointer to mii_bus structure @@ -166,6 +171,8 @@ int __of_mdiobus_register(struct mii_bus *mdio, struct device_node *np, * the device tree are populated after the bus has been registered */ mdio->phy_mask = ~0; + mdio->__unregister_callback = __of_mdiobus_unregister_callback; + of_node_get(np); device_set_node(&mdio->dev, of_fwnode_handle(np)); /* Get bus level PHY reset GPIO details */ @@ -177,7 +184,7 @@ int __of_mdiobus_register(struct mii_bus *mdio, struct device_node *np, /* Register the MDIO bus */ rc = __mdiobus_register(mdio, owner); if (rc) - return rc; + goto put_node; /* Loop over the child nodes and register a phy_device for each phy */ for_each_available_child_of_node(np, child) { @@ -237,6 +244,9 @@ int __of_mdiobus_register(struct mii_bus *mdio, struct device_node *np, unregister: of_node_put(child); mdiobus_unregister(mdio); + +put_node: + of_node_put(np); return rc; } EXPORT_SYMBOL(__of_mdiobus_register); diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index 25dcaa49ab8b..1229b8e4c53b 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -787,6 +787,9 @@ void mdiobus_unregister(struct mii_bus *bus) gpiod_set_value_cansleep(bus->reset_gpiod, 1); device_del(&bus->dev); + + if (bus->__unregister_callback) + bus->__unregister_callback(bus); } EXPORT_SYMBOL(mdiobus_unregister); diff --git a/include/linux/phy.h b/include/linux/phy.h index e5f1f41e399c..2b383da4d825 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -433,6 +433,9 @@ struct mii_bus { /** @shared: shared state across different PHYs */ struct phy_package_shared *shared[PHY_MAX_ADDR]; + + /** @__unregister_callback: called at the last step of unregistration */ + void (*__unregister_callback)(struct mii_bus *bus); }; #define to_mii_bus(d) container_of(d, struct mii_bus, dev)