From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60344) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aHTPB-0000vD-Pz for qemu-devel@nongnu.org; Fri, 08 Jan 2016 04:32:22 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aHTPA-0005Wv-QB for qemu-devel@nongnu.org; Fri, 08 Jan 2016 04:32:21 -0500 Received: from mail-wm0-x22f.google.com ([2a00:1450:400c:c09::22f]:35886) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aHTPA-0005Wk-KB for qemu-devel@nongnu.org; Fri, 08 Jan 2016 04:32:20 -0500 Received: by mail-wm0-x22f.google.com with SMTP id l65so127505465wmf.1 for ; Fri, 08 Jan 2016 01:32:20 -0800 (PST) From: Eric Auger Date: Fri, 8 Jan 2016 09:32:00 +0000 Message-Id: <1452245525-3886-4-git-send-email-eric.auger@linaro.org> In-Reply-To: <1452245525-3886-1-git-send-email-eric.auger@linaro.org> References: <1452245525-3886-1-git-send-email-eric.auger@linaro.org> Subject: [Qemu-devel] [PATCH v4 3/8] device_tree: introduce qemu_fdt_node_path List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: eric.auger@st.com, eric.auger@linaro.org, qemu-devel@nongnu.org, qemu-arm@nongnu.org, peter.maydell@linaro.org, david@gibson.dropbear.id.au, alex.williamson@redhat.com Cc: thomas.lendacky@amd.com, thuth@redhat.com, b.reynal@virtualopensystems.com, patches@linaro.org, crosthwaitepeter@gmail.com, suravee.suthikulpanit@amd.com, pbonzini@redhat.com, alex.bennee@linaro.org, christoffer.dall@linaro.org This new helper routine returns the node path of a device referred to by its node name and compat string. Signed-off-by: Eric Auger --- v1 -> v2: - move doc comment in header file - do not use a fixed size buffer - break on errors in while loop - use strcmp instead of strncmp RFC -> v1: - improve error handling according to Alex' comments --- device_tree.c | 37 +++++++++++++++++++++++++++++++++++++ include/sysemu/device_tree.h | 14 ++++++++++++++ 2 files changed, 51 insertions(+) diff --git a/device_tree.c b/device_tree.c index b262c2d..8441e01 100644 --- a/device_tree.c +++ b/device_tree.c @@ -231,6 +231,43 @@ static int findnode_nofail(void *fdt, const char *node_path) return offset; } +int qemu_fdt_node_path(void *fdt, const char *name, char *compat, + char **node_path) +{ + int offset, len, ret; + const char *iter_name; + unsigned int path_len = 16; + char *path; + + *node_path = NULL; + offset = fdt_node_offset_by_compatible(fdt, -1, compat); + + while (offset >= 0) { + iter_name = fdt_get_name(fdt, offset, &len); + if (!iter_name) { + offset = len; + break; + } + if (!strcmp(iter_name, name)) { + goto found; + } + offset = fdt_node_offset_by_compatible(fdt, offset, compat); + } + return offset; + +found: + path = g_malloc(path_len); + while ((ret = fdt_get_path(fdt, offset, path, path_len)) + == -FDT_ERR_NOSPACE) { + path_len += 16; + path = g_realloc(path, path_len); + } + if (!ret) { + *node_path = path; + } + return ret; +} + int qemu_fdt_setprop(void *fdt, const char *node_path, const char *property, const void *val, int size) { diff --git a/include/sysemu/device_tree.h b/include/sysemu/device_tree.h index fdf25a4..269cb1c 100644 --- a/include/sysemu/device_tree.h +++ b/include/sysemu/device_tree.h @@ -20,6 +20,20 @@ void *load_device_tree(const char *filename_path, int *sizep); void *load_device_tree_from_sysfs(void); #endif +/** + * qemu_fdt_node_path: return the node path of a device, given its + * node name and its compat string + * @fdt: pointer to the dt blob + * @name: device node name + * @compat: compatibility string of the device + * @node_path: returned node path + * + * upon success, the path is output at node_path address + * returns 0 on success, < 0 on failure + */ +int qemu_fdt_node_path(void *fdt, const char *name, char *compat, + char **node_path); + int qemu_fdt_setprop(void *fdt, const char *node_path, const char *property, const void *val, int size); int qemu_fdt_setprop_cell(void *fdt, const char *node_path, -- 1.9.1