From patchwork Thu Nov 30 15:24:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Herve Codina X-Patchwork-Id: 13474627 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="lJk5cY2e" Received: from relay9-d.mail.gandi.net (relay9-d.mail.gandi.net [217.70.183.199]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7EFD31A3; Thu, 30 Nov 2023 07:24:26 -0800 (PST) Received: by mail.gandi.net (Postfix) with ESMTPA id 72988FF806; Thu, 30 Nov 2023 15:24:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1701357865; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GPvyel4ZeW38fPIJ9TsfdFm6eZp6ZKA8PPSc++A7E08=; b=lJk5cY2ed3iNnANukJPQox3YYcMSQEsgyKi0f8gRc841baqVBOjsFIuHZzL4YrZRkcA5Q9 KF3RsiHyKNKFvHzlpo8RnKqxE7rhaKCMjLZNLj0ixfXCtkjEgWF7VTf2L6s6ALkYaEj4kv 8vroojrxIja/9rkH98cZqgkAbbLVu5CnY3XuYbFGVuqEFemIykIE8mWh2TG24z89moKLR9 fyB8p7U7FNpwvy0ardVyl1zNQEOloHo5LoboJhLiCM1GNRu+3FBOxyTdB4W+KawN/R2Ae9 a6u5xHTTu4AS6qqFFID4OI1r22cJdaPUN9v+xlvEOET6Rd0piK/dO6LP54Canw== From: Herve Codina To: Greg Kroah-Hartman , "Rafael J. Wysocki" , Bjorn Helgaas , Lizhi Hou , Rob Herring Cc: Max Zhen , Sonal Santan , Stefano Stabellini , Jonathan Cameron , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Allan Nielsen , Horatiu Vultur , Steen Hegelund , Thomas Petazzoni , Herve Codina Subject: [PATCH 1/2] driver core: Introduce device_{add,remove}_of_node() Date: Thu, 30 Nov 2023 16:24:03 +0100 Message-ID: <20231130152418.680966-2-herve.codina@bootlin.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231130152418.680966-1-herve.codina@bootlin.com> References: <20231130152418.680966-1-herve.codina@bootlin.com> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-GND-Sasl: herve.codina@bootlin.com An of_node can be duplicated from an existing device using device_set_of_node_from_dev() or initialized using device_set_node() In both cases, these functions have to be called before the device_add() call in order to have the of_node link created in the device sysfs directory. Further more, these function cannot prevent any of_node and/or fwnode overwrites. When adding an of_node on an already present device, the following operations need to be done: - Attach the of_node if no of_node were already attached - Attach the of_node as a fwnode if no fwnode were already attached - Create the of_node sysfs link if needed This is the purpose of device_add_of_node(). device_remove_of_node() reverts the operations done by device_add_of_node(). Signed-off-by: Herve Codina --- drivers/base/core.c | 74 ++++++++++++++++++++++++++++++++++++++++++ include/linux/device.h | 2 ++ 2 files changed, 76 insertions(+) diff --git a/drivers/base/core.c b/drivers/base/core.c index 2926f3b1f868..ac026187ac6a 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -5046,6 +5046,80 @@ void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode) } EXPORT_SYMBOL_GPL(set_secondary_fwnode); +/** + * device_remove_of_node - Remove an of_node from a device + * @dev: device whose device-tree node is being removed + */ +void device_remove_of_node(struct device *dev) +{ + dev = get_device(dev); + if (!dev) + return; + + if (!dev->of_node) + goto end; + + sysfs_remove_link(&dev->kobj, "of_node"); + + if (dev->fwnode == of_fwnode_handle(dev->of_node)) + dev->fwnode = NULL; + + of_node_put(dev->of_node); + dev->of_node = NULL; + +end: + put_device(dev); +} +EXPORT_SYMBOL_GPL(device_remove_of_node); + +/** + * device_add_of_node - Add an of_node to an existing device + * @dev: device whose device-tree node is being added + * @of_node: of_node to add + */ +void device_add_of_node(struct device *dev, struct device_node *of_node) +{ + int ret; + + if (!of_node) + return; + + dev = get_device(dev); + if (!dev) + return; + + if (dev->of_node) { + dev_warn(dev, "Replace node %pOF with %pOF\n", dev->of_node, of_node); + device_remove_of_node(dev); + } + + dev->of_node = of_node_get(of_node); + + if (!dev->fwnode) + dev->fwnode = of_fwnode_handle(of_node); + + if (!dev->p) { + /* + * device_add() was not previously called. + * The of_node link will be created when device_add() is called. + */ + goto end; + } + + /* + * device_add() was previously called and so the of_node link was not + * created by device_add_class_symlinks(). + * Create this link now. + */ + ret = sysfs_create_link(&dev->kobj, of_node_kobj(of_node), "of_node"); + if (ret) + dev_warn(dev, "Error %d creating of_node link\n", ret); + +end: + put_device(dev); +} +EXPORT_SYMBOL_GPL(device_add_of_node); + /** * device_set_of_node_from_dev - reuse device-tree node of another device * @dev: device whose device-tree node is being set diff --git a/include/linux/device.h b/include/linux/device.h index d7a72a8749ea..2b093e62907a 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -1128,6 +1128,8 @@ int device_offline(struct device *dev); int device_online(struct device *dev); void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode); void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode); +void device_add_of_node(struct device *dev, struct device_node *of_node); +void device_remove_of_node(struct device *dev); void device_set_of_node_from_dev(struct device *dev, const struct device *dev2); void device_set_node(struct device *dev, struct fwnode_handle *fwnode);