Some properties may contain multiple values, these values may need to be added to the property respectively. this patch provides this functionality. The main purpose of fdt_append_prop() is to append the values to a existing property, or create a new property if it dose not exist.
Signed-off-by: Minghuan Lian <[email protected]> --- libfdt/fdt_rw.c | 27 +++++++++++++++++++++++++++ libfdt/libfdt.h | 30 ++++++++++++++++++++++++++++++ 2 files changed, 57 insertions(+), 0 deletions(-) diff --git a/libfdt/fdt_rw.c b/libfdt/fdt_rw.c index 994037b..0ee578e 100644 --- a/libfdt/fdt_rw.c +++ b/libfdt/fdt_rw.c @@ -289,6 +289,33 @@ int fdt_setprop(void *fdt, int nodeoffset, const char *name, return 0; } +int fdt_append_prop(void *fdt, int nodeoffset, const char *name, + const void *val, int len) +{ + struct fdt_property *prop; + int err, oldlen, newlen; + + FDT_RW_CHECK_HEADER(fdt); + + prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen); + if (prop) { + newlen = len + oldlen; + err = _fdt_splice_struct(fdt, prop->data, + FDT_TAGALIGN(oldlen), + FDT_TAGALIGN(newlen)); + if (err) + return err; + prop->len = cpu_to_fdt32(newlen); + memcpy(prop->data + oldlen, val, len); + } else { + err = _fdt_add_property(fdt, nodeoffset, name, len, &prop); + if (err) + return err; + memcpy(prop->data, val, len); + } + return 0; +} + int fdt_delprop(void *fdt, int nodeoffset, const char *name) { struct fdt_property *prop; diff --git a/libfdt/libfdt.h b/libfdt/libfdt.h index 55f3eb3..ff4161b 100644 --- a/libfdt/libfdt.h +++ b/libfdt/libfdt.h @@ -1068,6 +1068,36 @@ int fdt_setprop(void *fdt, int nodeoffset, const char *name, const void *val, int len); /** + * fdt_append_prop - append or create a property + * @fdt: pointer to the device tree blob + * @nodeoffset: offset of the node whose property to change + * @name: name of the property to append + * @val: pointer to data to append to the property value + * @len: length of the property value + * + * fdt_append_prop() appends the value to the named property in the given + * node, creating the property if it does not already exist. + * + * This function may change data from the blob, and will + * therefore change the offsets of some existing nodes. + * + * returns: + * 0, on success + * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to + * contain the new property value + * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag + * -FDT_ERR_BADLAYOUT, + * -FDT_ERR_BADMAGIC, + * -FDT_ERR_BADVERSION, + * -FDT_ERR_BADSTATE, + * -FDT_ERR_BADSTRUCTURE, + * -FDT_ERR_BADLAYOUT, + * -FDT_ERR_TRUNCATED, standard meanings + */ +int fdt_append_prop(void *fdt, int nodeoffset, const char *name, + const void *val, int len); + +/** * fdt_setprop_cell - set a property to a single cell value * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change -- 1.7.0.4 _______________________________________________ devicetree-discuss mailing list [email protected] https://lists.ozlabs.org/listinfo/devicetree-discuss
