Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757346Ab1ETW0N (ORCPT ); Fri, 20 May 2011 18:26:13 -0400 Received: from mail3.caviumnetworks.com ([12.108.191.235]:2111 "EHLO mail3.caviumnetworks.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757297Ab1ETWZ4 (ORCPT ); Fri, 20 May 2011 18:25:56 -0400 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 v4 2/6] of: Make of_find_node_by_path() traverse /aliases for relative paths. Date: Fri, 20 May 2011 15:25:39 -0700 Message-Id: <1305930343-31259-3-git-send-email-ddaney@caviumnetworks.com> X-Mailer: git-send-email 1.7.2.3 In-Reply-To: <1305930343-31259-1-git-send-email-ddaney@caviumnetworks.com> References: <1305930343-31259-1-git-send-email-ddaney@caviumnetworks.com> X-OriginalArrivalTime: 20 May 2011 22:25:56.0048 (UTC) FILETIME=[E2FB0500:01CC173C] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2644 Lines: 92 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 --- drivers/of/base.c | 48 +++++++++++++++++++++++++++++++++++++++++++++--- 1 files changed, 45 insertions(+), 3 deletions(-) diff --git a/drivers/of/base.c b/drivers/of/base.c index 632ebae..279134b 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -340,22 +340,64 @@ 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. */ struct device_node *of_find_node_by_path(const char *path) { - struct device_node *np = allnodes; + struct device_node *np = NULL; + struct device_node *aliases = NULL; + char *alias = NULL; + char *new_path = NULL; read_lock(&devtree_lock); - for (; np; np = np->allnext) { + + if (path[0] != '/') { + const char *ps; + aliases = of_find_node_by_path("/aliases"); + if (!aliases) + goto out; + + ps = strchr(path, '/'); + if (ps) { + size_t len = ps - path; + alias = kstrndup(path, len, GFP_KERNEL); + if (!alias) + goto out; + path = of_get_property(aliases, alias, NULL); + if (!path) + goto out; + + len = strlen(path) + strlen(ps) + 1; + new_path = kmalloc(len, GFP_KERNEL); + if (!new_path) + goto out; + strcpy(new_path, path); + strcat(new_path, ps); + path = new_path; + } else { + path = of_get_property(aliases, path, NULL); + } + if (!path) + goto out; + } + + for (np = allnodes; 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); + kfree(alias); + kfree(new_path); return np; } EXPORT_SYMBOL(of_find_node_by_path); -- 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/