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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 C0C5DC3A5A8 for ; Mon, 2 Sep 2019 08:33:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9B9BC21874 for ; Mon, 2 Sep 2019 08:33:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730330AbfIBIck (ORCPT ); Mon, 2 Sep 2019 04:32:40 -0400 Received: from mga01.intel.com ([192.55.52.88]:25919 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730266AbfIBIcj (ORCPT ); Mon, 2 Sep 2019 04:32:39 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Sep 2019 01:32:39 -0700 X-IronPort-AV: E=Sophos;i="5.64,457,1559545200"; d="scan'208";a="172875090" Received: from paasikivi.fi.intel.com ([10.237.72.42]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Sep 2019 01:32:36 -0700 Received: from punajuuri.localdomain (punajuuri.localdomain [192.168.240.130]) by paasikivi.fi.intel.com (Postfix) with ESMTP id D24C220B48; Mon, 2 Sep 2019 11:32:33 +0300 (EEST) Received: from sailus by punajuuri.localdomain with local (Exim 4.92) (envelope-from ) id 1i4hlQ-0005Jb-96; Mon, 02 Sep 2019 11:32:40 +0300 From: Sakari Ailus To: Petr Mladek , linux-kernel@vger.kernel.org, rafael@kernel.org Cc: Andy Shevchenko , linux-acpi@vger.kernel.org, devicetree@vger.kernel.org, Rob Herring , Heikki Krogerus Subject: [PATCH v4 04/11] device property: Add functions for accessing node's parents Date: Mon, 2 Sep 2019 11:32:33 +0300 Message-Id: <20190902083240.20367-5-sakari.ailus@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190902083240.20367-1-sakari.ailus@linux.intel.com> References: <20190902083240.20367-1-sakari.ailus@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org Add two convenience functions for accessing node's parents: fwnode_count_parents() returns the number of parent nodes a given node has. fwnode_get_nth_parent() returns node's parent at a given distance from the node itself. Signed-off-by: Sakari Ailus --- drivers/base/property.c | 46 ++++++++++++++++++++++++++++++++++++++++ include/linux/property.h | 3 +++ 2 files changed, 49 insertions(+) diff --git a/drivers/base/property.c b/drivers/base/property.c index 3d9dffbe96378..d2461d79139f3 100644 --- a/drivers/base/property.c +++ b/drivers/base/property.c @@ -590,6 +590,52 @@ struct fwnode_handle *fwnode_get_next_parent(struct fwnode_handle *fwnode) } EXPORT_SYMBOL_GPL(fwnode_get_next_parent); +/** + * fwnode_count_parents - Return the number of parents a node has + * @fwnode: The node the parents of which are to be counted + * + * Returns the number of parents a node has. + */ +unsigned int fwnode_count_parents(const struct fwnode_handle *fwnode) +{ + struct fwnode_handle *__fwnode; + unsigned int count; + + __fwnode = fwnode_get_parent(fwnode); + + for (count = 0; __fwnode; count++) + __fwnode = fwnode_get_next_parent(__fwnode); + + return count; +} +EXPORT_SYMBOL_GPL(fwnode_count_parents); + +/** + * fwnode_get_nth_parent - Return an nth parent of a node + * @fwnode: The node the parent of which is requested + * @depth: Distance of the parent from the node + * + * Returns the nth parent of a node. If @depth is 0, the functionality is + * equivalent to fwnode_handle_get(). For @depth == 1, it is fwnode_get_parent() + * and so on. + * + * The caller is responsible for calling fwnode_handle_put() for the returned + * node. + */ +struct fwnode_handle *fwnode_get_nth_parent(struct fwnode_handle *fwnode, + unsigned int depth) +{ + unsigned int i; + + fwnode_handle_get(fwnode); + + for (i = 0; i < depth && fwnode; i++) + fwnode = fwnode_get_next_parent(fwnode); + + return fwnode; +} +EXPORT_SYMBOL_GPL(fwnode_get_nth_parent); + /** * fwnode_get_next_child_node - Return the next child node handle for a node * @fwnode: Firmware node to find the next child node for. diff --git a/include/linux/property.h b/include/linux/property.h index 421c76e53708d..5450e7ec219ac 100644 --- a/include/linux/property.h +++ b/include/linux/property.h @@ -83,6 +83,9 @@ struct fwnode_handle *fwnode_find_reference(const struct fwnode_handle *fwnode, struct fwnode_handle *fwnode_get_parent(const struct fwnode_handle *fwnode); struct fwnode_handle *fwnode_get_next_parent( struct fwnode_handle *fwnode); +unsigned int fwnode_count_parents(const struct fwnode_handle *fwn); +struct fwnode_handle *fwnode_get_nth_parent(struct fwnode_handle *fwn, + unsigned int depth); struct fwnode_handle *fwnode_get_next_child_node( const struct fwnode_handle *fwnode, struct fwnode_handle *child); struct fwnode_handle *fwnode_get_next_available_child_node( -- 2.20.1