diff options
| -rw-r--r-- | include/libfdt.h | 103 | ||||
| -rw-r--r-- | lib/libfdt/fdt.c | 9 | ||||
| -rw-r--r-- | lib/libfdt/fdt_ro.c | 123 | ||||
| -rw-r--r-- | lib/libfdt/libfdt_internal.h | 1 |
4 files changed, 200 insertions, 36 deletions
diff --git a/include/libfdt.h b/include/libfdt.h index d23d40e..de82ed5 100644 --- a/include/libfdt.h +++ b/include/libfdt.h @@ -343,6 +343,75 @@ int fdt_path_offset(const void *fdt, const char *path); const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp); /** + * fdt_first_property_offset - find the offset of a node's first property + * @fdt: pointer to the device tree blob + * @nodeoffset: structure block offset of a node + * + * fdt_first_property_offset() finds the first property of the node at + * the given structure block offset. + * + * returns: + * structure block offset of the property (>=0), on success + * -FDT_ERR_NOTFOUND, if the requested node has no properties + * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag + * -FDT_ERR_BADMAGIC, + * -FDT_ERR_BADVERSION, + * -FDT_ERR_BADSTATE, + * -FDT_ERR_BADSTRUCTURE, + * -FDT_ERR_TRUNCATED, standard meanings. + */ +int fdt_first_property_offset(const void *fdt, int nodeoffset); + +/** + * fdt_next_property_offset - step through a node's properties + * @fdt: pointer to the device tree blob + * @offset: structure block offset of a property + * + * fdt_next_property_offset() finds the property immediately after the + * one at the given structure block offset. This will be a property + * of the same node as the given property. + * + * returns: + * structure block offset of the next property (>=0), on success + * -FDT_ERR_NOTFOUND, if the given property is the last in its node + * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag + * -FDT_ERR_BADMAGIC, + * -FDT_ERR_BADVERSION, + * -FDT_ERR_BADSTATE, + * -FDT_ERR_BADSTRUCTURE, + * -FDT_ERR_TRUNCATED, standard meanings. + */ +int fdt_next_property_offset(const void *fdt, int offset); + +/** + * fdt_get_property_by_offset - retrieve the property at a given offset + * @fdt: pointer to the device tree blob + * @offset: offset of the property to retrieve + * @lenp: pointer to an integer variable (will be overwritten) or NULL + * + * fdt_get_property_by_offset() retrieves a pointer to the + * fdt_property structure within the device tree blob at the given + * offset. If lenp is non-NULL, the length of the property value is + * also returned, in the integer pointed to by lenp. + * + * returns: + * pointer to the structure representing the property + * if lenp is non-NULL, *lenp contains the length of the property + * value (>=0) + * NULL, on error + * if lenp is non-NULL, *lenp contains an error code (<0): + * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag + * -FDT_ERR_BADMAGIC, + * -FDT_ERR_BADVERSION, + * -FDT_ERR_BADSTATE, + * -FDT_ERR_BADSTRUCTURE, + * -FDT_ERR_TRUNCATED, standard meanings + */ +const struct fdt_property *fdt_get_property_by_offset(const void *fdt, + int offset, + int *lenp); + +/** * fdt_get_property_namelen - find a property based on substring * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to find @@ -396,6 +465,40 @@ static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset, } /** + * fdt_getprop_by_offset - retrieve the value of a property at a given offset + * @fdt: pointer to the device tree blob + * @ffset: offset of the property to read + * @namep: pointer to a string variable (will be overwritten) or NULL + * @lenp: pointer to an integer variable (will be overwritten) or NULL + * + * fdt_getprop_by_offset() retrieves a pointer to the value of the + * property at structure block offset 'offset' (this will be a pointer + * to within the device blob itself, not a copy of the value). If + * lenp is non-NULL, the length of the property value is also + * returned, in the integer pointed to by lenp. If namep is non-NULL, + * the property's namne will also be returned in the char * pointed to + * by namep (this will be a pointer to within the device tree's string + * block, not a new copy of the name). + * + * returns: + * pointer to the property's value + * if lenp is non-NULL, *lenp contains the length of the property + * value (>=0) + * if namep is non-NULL *namep contiains a pointer to the property + * name. + * NULL, on error + * if lenp is non-NULL, *lenp contains an error code (<0): + * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag + * -FDT_ERR_BADMAGIC, + * -FDT_ERR_BADVERSION, + * -FDT_ERR_BADSTATE, + * -FDT_ERR_BADSTRUCTURE, + * -FDT_ERR_TRUNCATED, standard meanings + */ +const void *fdt_getprop_by_offset(const void *fdt, int offset, + const char **namep, int *lenp); + +/** * fdt_getprop_namelen - get property value based on substring * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to find diff --git a/lib/libfdt/fdt.c b/lib/libfdt/fdt.c index b09ea6f..4157b21 100644 --- a/lib/libfdt/fdt.c +++ b/lib/libfdt/fdt.c @@ -153,6 +153,15 @@ int _fdt_check_node_offset(const void *fdt, int offset) return offset; } +int _fdt_check_prop_offset(const void *fdt, int offset) +{ + if ((offset < 0) || (offset % FDT_TAGSIZE) + || (fdt_next_tag(fdt, offset, &offset) != FDT_PROP)) + return -FDT_ERR_BADOFFSET; + + return offset; +} + int fdt_next_node(const void *fdt, int offset, int *depth) { int nextoffset = 0; diff --git a/lib/libfdt/fdt_ro.c b/lib/libfdt/fdt_ro.c index 91a354e..1933010 100644 --- a/lib/libfdt/fdt_ro.c +++ b/lib/libfdt/fdt_ro.c @@ -109,6 +109,30 @@ int fdt_num_mem_rsv(const void *fdt) return i; } +static int _nextprop(const void *fdt, int offset) +{ + uint32_t tag; + int nextoffset; + + do { + tag = fdt_next_tag(fdt, offset, &nextoffset); + + switch (tag) { + case FDT_END: + if (nextoffset >= 0) + return -FDT_ERR_BADSTRUCTURE; + else + return nextoffset; + + case FDT_PROP: + return offset; + } + offset = nextoffset; + } while (tag == FDT_NOP); + + return -FDT_ERR_NOTFOUND; +} + int fdt_subnode_offset_namelen(const void *fdt, int offset, const char *name, int namelen) { @@ -198,52 +222,66 @@ const char *fdt_get_name(const void *fdt, int nodeoffset, int *len) return NULL; } -const struct fdt_property *fdt_get_property_namelen(const void *fdt, - int nodeoffset, - const char *name, - int namelen, int *lenp) +int fdt_first_property_offset(const void *fdt, int nodeoffset) +{ + int offset; + + if ((offset = _fdt_check_node_offset(fdt, nodeoffset)) < 0) + return offset; + + return _nextprop(fdt, offset); +} + +int fdt_next_property_offset(const void *fdt, int offset) +{ + if ((offset = _fdt_check_prop_offset(fdt, offset)) < 0) + return offset; + + return _nextprop(fdt, offset); +} + +const struct fdt_property *fdt_get_property_by_offset(const void *fdt, + int offset, + int *lenp) { - uint32_t tag; - const struct fdt_property *prop; - int offset, nextoffset; int err; + const struct fdt_property *prop; - if (((err = fdt_check_header(fdt)) != 0) - || ((err = _fdt_check_node_offset(fdt, nodeoffset)) < 0)) - goto fail; + if ((err = _fdt_check_prop_offset(fdt, offset)) < 0) { + if (lenp) + *lenp = err; + return NULL; + } - nextoffset = err; - do { - offset = nextoffset; + prop = _fdt_offset_ptr(fdt, offset); - tag = fdt_next_tag(fdt, offset, &nextoffset); - switch (tag) { - case FDT_END: - if (nextoffset < 0) - err = nextoffset; - else - /* FDT_END tag with unclosed nodes */ - err = -FDT_ERR_BADSTRUCTURE; - goto fail; + if (lenp) + *lenp = fdt32_to_cpu(prop->len); - case FDT_PROP: - prop = _fdt_offset_ptr(fdt, offset); - if (_fdt_string_eq(fdt, fdt32_to_cpu(prop->nameoff), - name, namelen)) { - /* Found it! */ - if (lenp) - *lenp = fdt32_to_cpu(prop->len); - - return prop; - } + return prop; +} + +const struct fdt_property *fdt_get_property_namelen(const void *fdt, + int offset, + const char *name, + int namelen, int *lenp) +{ + for (offset = fdt_first_property_offset(fdt, offset); + (offset >= 0); + (offset = fdt_next_property_offset(fdt, offset))) { + const struct fdt_property *prop; + + if (!(prop = fdt_get_property_by_offset(fdt, offset, lenp))) { + offset = -FDT_ERR_INTERNAL; break; } - } while ((tag != FDT_BEGIN_NODE) && (tag != FDT_END_NODE)); + if (_fdt_string_eq(fdt, fdt32_to_cpu(prop->nameoff), + name, namelen)) + return prop; + } - err = -FDT_ERR_NOTFOUND; - fail: if (lenp) - *lenp = err; + *lenp = offset; return NULL; } @@ -267,6 +305,19 @@ const void *fdt_getprop_namelen(const void *fdt, int nodeoffset, return prop->data; } +const void *fdt_getprop_by_offset(const void *fdt, int offset, + const char **namep, int *lenp) +{ + const struct fdt_property *prop; + + prop = fdt_get_property_by_offset(fdt, offset, lenp); + if (!prop) + return NULL; + if (namep) + *namep = fdt_string(fdt, fdt32_to_cpu(prop->nameoff)); + return prop->data; +} + const void *fdt_getprop(const void *fdt, int nodeoffset, const char *name, int *lenp) { diff --git a/lib/libfdt/libfdt_internal.h b/lib/libfdt/libfdt_internal.h index d2dcbd6..381133b 100644 --- a/lib/libfdt/libfdt_internal.h +++ b/lib/libfdt/libfdt_internal.h @@ -63,6 +63,7 @@ } int _fdt_check_node_offset(const void *fdt, int offset); +int _fdt_check_prop_offset(const void *fdt, int offset); const char *_fdt_find_string(const char *strtab, int tabsize, const char *s); int _fdt_node_end_offset(void *fdt, int nodeoffset); |