Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932540Ab1CDTpS (ORCPT ); Fri, 4 Mar 2011 14:45:18 -0500 Received: from mail3.caviumnetworks.com ([12.108.191.235]:11794 "EHLO mail3.caviumnetworks.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760014Ab1CDTmm (ORCPT ); Fri, 4 Mar 2011 14:42:42 -0500 From: David Daney To: linux-mips@linux-mips.org, ralf@linux-mips.org, devicetree-discuss@lists.ozlabs.org, grant.likely@secretlab.ca, linux-kernel@vger.kernel.org Cc: David Daney Subject: [RFC PATCH v2 03/12] of: Make of_find_node_by_path() traverse /aliases for relative paths. Date: Fri, 4 Mar 2011 11:42:15 -0800 Message-Id: <1299267744-17278-4-git-send-email-ddaney@caviumnetworks.com> X-Mailer: git-send-email 1.7.2.3 In-Reply-To: <1299267744-17278-1-git-send-email-ddaney@caviumnetworks.com> References: <1299267744-17278-1-git-send-email-ddaney@caviumnetworks.com> X-OriginalArrivalTime: 04 Mar 2011 19:42:42.0403 (UTC) FILETIME=[53B4A330:01CBDAA4] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2322 Lines: 74 Currently all paths passed to of_find_node_by_path() must begin with a '/', indicating a full path to the desired node. Augment the look-up code so that if a path does *not* begin with '/', the path is used as the name of an /aliases property. The value of this alias is then used as the full node path to be found. Signed-off-by: David Daney --- This patch is unchanged from the previous version I send separately. I have not forgotten about Grant's feedback, just deferred it to the next version. drivers/of/base.c | 24 +++++++++++++++++++++++- 1 files changed, 23 insertions(+), 1 deletions(-) diff --git a/drivers/of/base.c b/drivers/of/base.c index 710b53b..e63da9c 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -340,7 +340,10 @@ EXPORT_SYMBOL(of_get_next_child); /** * of_find_node_by_path - Find a node matching a full OF path - * @path: The full path to match + * @path: Either the full path to match, or if the path does not + * start with '/', the name of a property of the /aliases + * node (an alias). In the case of an alias, the node + * matching the alias' value will be returned. * * Returns a node pointer with refcount incremented, use * of_node_put() on it when done. @@ -348,13 +351,32 @@ EXPORT_SYMBOL(of_get_next_child); struct device_node *of_find_node_by_path(const char *path) { struct device_node *np = allnodes; + struct device_node *aliases = NULL; read_lock(&devtree_lock); + + if (path[0] != '/') { + aliases = of_find_node_by_path("/aliases"); + if (!aliases) + goto out; + path = of_get_property(aliases, path, NULL); + /* + * The alias must begin with '/', otherwise we could + * get stuck in an endless loop and blow out the + * stack. + */ + if (!path || path[0] != '/') + goto out; + } + for (; np; np = np->allnext) { if (np->full_name && (of_node_cmp(np->full_name, path) == 0) && of_node_get(np)) break; } +out: + if (aliases) + of_node_put(aliases); read_unlock(&devtree_lock); return np; } -- 1.7.2.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/