From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756541AbcBIFF2 (ORCPT ); Tue, 9 Feb 2016 00:05:28 -0500 Received: from mail.kernel.org ([198.145.29.136]:59727 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752220AbcBIFFV (ORCPT ); Tue, 9 Feb 2016 00:05:21 -0500 MIME-Version: 1.0 In-Reply-To: <1454641552-12576-17-git-send-email-zhaoshenglong@huawei.com> References: <1454641552-12576-1-git-send-email-zhaoshenglong@huawei.com> <1454641552-12576-17-git-send-email-zhaoshenglong@huawei.com> From: Rob Herring Date: Mon, 8 Feb 2016 23:04:56 -0600 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v4 16/17] FDT: Add a helper to get specified name subnode To: Shannon Zhao Cc: "linux-arm-kernel@lists.infradead.org" , Ard Biesheuvel , Stefano Stabellini , david.vrabel@citrix.com, Catalin Marinas , Will Deacon , Mark Rutland , julien.grall@citrix.com, "xen-devel@lists.xen.org" , "devicetree@vger.kernel.org" , "linux-efi@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Ian Campbell , shannon.zhao@linaro.org, peter.huangpeng@huawei.com Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 4, 2016 at 9:05 PM, Shannon Zhao wrote: > From: Shannon Zhao > > Sometimes it needs to check if there is a node in FDT by full path. I'm confused. Are you searching by full path or... > Introduce this helper to get the specified name subnode if it exists. name of sub node? Either way, fdt_subnode_offset or fdt_path_offset doesn't work? > > Signed-off-by: Shannon Zhao > --- > CC: Rob Herring > --- > drivers/of/fdt.c | 25 +++++++++++++++++++++++++ > include/linux/of_fdt.h | 2 ++ > 2 files changed, 27 insertions(+) > > diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c > index 655f79d..eacb188 100644 > --- a/drivers/of/fdt.c > +++ b/drivers/of/fdt.c > @@ -645,6 +645,31 @@ 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; > + > + for (offset = fdt_first_subnode(blob, node); > + offset >= 0; > + offset = fdt_next_subnode(blob, offset)) { > + pathp = fdt_get_name(blob, offset, NULL); > + if (strcmp(pathp, uname) == 0) > + return offset; > + } > + > + 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); > -- > 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