From patchwork Sat Jan 23 03:19:43 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shannon Zhao X-Patchwork-Id: 60225 Delivered-To: patch@linaro.org Received: by 10.112.130.2 with SMTP id oa2csp246961lbb; Fri, 22 Jan 2016 19:22:56 -0800 (PST) X-Received: by 10.66.255.70 with SMTP id ao6mr9244187pad.64.1453519365212; Fri, 22 Jan 2016 19:22:45 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id v13si13898089pas.108.2016.01.22.19.22.44; Fri, 22 Jan 2016 19:22:45 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of devicetree-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of devicetree-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=devicetree-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756370AbcAWDWg (ORCPT + 6 others); Fri, 22 Jan 2016 22:22:36 -0500 Received: from szxga01-in.huawei.com ([58.251.152.64]:44487 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755770AbcAWDVA (ORCPT ); Fri, 22 Jan 2016 22:21:00 -0500 Received: from 172.24.1.48 (EHLO szxeml425-hub.china.huawei.com) ([172.24.1.48]) by szxrg01-dlp.huawei.com (MOS 4.3.7-GA FastPath queued) with ESMTP id DDP64723; Sat, 23 Jan 2016 11:20:55 +0800 (CST) Received: from HGHY1Z002260041.china.huawei.com (10.177.16.142) by szxeml425-hub.china.huawei.com (10.82.67.180) with Microsoft SMTP Server id 14.3.235.1; Sat, 23 Jan 2016 11:20:44 +0800 From: Shannon Zhao To: , , , , CC: , , , , , , , , , , Rob Herring Subject: [PATCH v3 16/17] FDT: Add a helper to get specified name subnode Date: Sat, 23 Jan 2016 11:19:43 +0800 Message-ID: <1453519184-11908-17-git-send-email-zhaoshenglong@huawei.com> X-Mailer: git-send-email 1.9.0.msysgit.0 In-Reply-To: <1453519184-11908-1-git-send-email-zhaoshenglong@huawei.com> References: <1453519184-11908-1-git-send-email-zhaoshenglong@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.177.16.142] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020205.56A2F197.00F5, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 60c7146b3e75912fa343b8d917209b72 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org From: Shannon Zhao Sometimes it needs to check if there is a node in FDT by full path. Introduce this helper to get the specified name subnode if it exists. Signed-off-by: Shannon Zhao --- CC: Rob Herring --- drivers/of/fdt.c | 35 +++++++++++++++++++++++++++++++++++ include/linux/of_fdt.h | 2 ++ 2 files changed, 37 insertions(+) -- 2.0.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 655f79d..112ec16 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -645,6 +645,41 @@ int __init of_scan_flat_dt(int (*it)(unsigned long node, } /** + * of_get_flat_dt_subnode_by_name - get subnode of specified node by name + * + * @node: the parent node + * @uname: the name of subnode + * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none + */ + +int of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname) +{ + const void *blob = initial_boot_params; + int offset; + const char *pathp; + + /* Find first subnode if it exists */ + offset = fdt_first_subnode(blob, node); + if (offset < 0) + return -FDT_ERR_NOTFOUND; + pathp = fdt_get_name(blob, offset, NULL); + if (strncmp(pathp, uname, strlen(uname)) == 0) + return offset; + + /* Find other subnodes */ + do { + offset = fdt_next_subnode(blob, offset); + if (offset < 0) + return -FDT_ERR_NOTFOUND; + pathp = fdt_get_name(blob, offset, NULL); + if (strncmp(pathp, uname, strlen(uname)) == 0) + return offset; + } while (offset >= 0); + + return -FDT_ERR_NOTFOUND; +} + +/** * of_get_flat_dt_root - find the root node in the flat blob */ unsigned long __init of_get_flat_dt_root(void) diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h index df9ef38..fc28162 100644 --- a/include/linux/of_fdt.h +++ b/include/linux/of_fdt.h @@ -52,6 +52,8 @@ extern char __dtb_end[]; extern int of_scan_flat_dt(int (*it)(unsigned long node, const char *uname, int depth, void *data), void *data); +extern int of_get_flat_dt_subnode_by_name(unsigned long node, + const char *uname); extern const void *of_get_flat_dt_prop(unsigned long node, const char *name, int *size); extern int of_flat_dt_is_compatible(unsigned long node, const char *name);