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: 8095841 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 11675BEEE5 for ; Sat, 23 Jan 2016 03:28:09 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 46204205B7 for ; Sat, 23 Jan 2016 03:28:08 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 745A5205B6 for ; Sat, 23 Jan 2016 03:28:07 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1aMopS-0007yS-7t; Sat, 23 Jan 2016 03:25:34 +0000 Received: from szxga01-in.huawei.com ([58.251.152.64]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1aMomn-0004IH-Qt for linux-arm-kernel@lists.infradead.org; Sat, 23 Jan 2016 03:22:53 +0000 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: , , , , 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160122_192250_715949_5BBABF50 X-CRM114-Status: GOOD ( 12.08 ) X-Spam-Score: -4.2 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, linux-efi@vger.kernel.org, ian.campbell@citrix.com, catalin.marinas@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, xen-devel@lists.xen.org, julien.grall@citrix.com, shannon.zhao@linaro.org, peter.huangpeng@huawei.com Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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(+) 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);