From 3bc37a50e0db9978c6fbb1b2b6c3a351cebe631e Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Sat, 17 Oct 2015 19:41:14 -0600 Subject: [PATCH] fdt: Add a function to look up a /chosen property It is sometimes useful to find a property in the chosen node. Add a function for this. Signed-off-by: Simon Glass Signed-off-by: Michal Simek --- include/fdtdec.h | 11 ++++++++++- lib/fdtdec.c | 15 ++++++++++----- 2 files changed, 20 insertions(+), 6 deletions(-) diff --git a/include/fdtdec.h b/include/fdtdec.h index 2de6dda..9fcc7a1 100644 --- a/include/fdtdec.h +++ b/include/fdtdec.h @@ -628,7 +628,16 @@ int fdtdec_get_alias_seq(const void *blob, const char *base, int node, int *seqp); /** - * Get the offset of the given chosen node + * Get a property from the /chosen node + * + * @param blob Device tree blob (if NULL, then NULL is returned) + * @param name Property name to look up + * @return Value of property, or NULL if it does not exist + */ +const char *fdtdec_get_chosen_prop(const void *blob, const char *name); + +/** + * Get the offset of the given /chosen node * * This looks up a property in /chosen containing the path to another node, * then finds the offset of that node. diff --git a/lib/fdtdec.c b/lib/fdtdec.c index 9db033a..e1df144 100644 --- a/lib/fdtdec.c +++ b/lib/fdtdec.c @@ -601,16 +601,21 @@ int fdtdec_get_alias_seq(const void *blob, const char *base, int offset, return -ENOENT; } -int fdtdec_get_chosen_node(const void *blob, const char *name) +const char *fdtdec_get_chosen_prop(const void *blob, const char *name) { - const char *prop; int chosen_node; - int len; if (!blob) - return -FDT_ERR_NOTFOUND; + return NULL; chosen_node = fdt_path_offset(blob, "/chosen"); - prop = fdt_getprop(blob, chosen_node, name, &len); + return fdt_getprop(blob, chosen_node, name, NULL); +} + +int fdtdec_get_chosen_node(const void *blob, const char *name) +{ + const char *prop; + + prop = fdtdec_get_chosen_prop(blob, name); if (!prop) return -FDT_ERR_NOTFOUND; return fdt_path_offset(blob, prop);