Signed-off-by: Wolfgang Grandegger wg@grandegger.com Acked-by: Gerald Van Baren vanbaren@cideas.com ---
Previously published by WolfgangG, added my ack.
include/libfdt.h | 6 ++ libfdt/fdt_ro.c | 161 ++++++++++++++++++++++++++++++++++++++++++++++++------ 2 files changed, 149 insertions(+), 18 deletions(-)
diff --git a/include/libfdt.h b/include/libfdt.h index e080028..340e89d 100644 --- a/include/libfdt.h +++ b/include/libfdt.h @@ -78,6 +78,12 @@ int fdt_subnode_offset_namelen(const void *fdt, int parentoffset, int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
int fdt_find_node_by_path(const void *fdt, const char *path); +int fdt_find_node_by_type(const void *fdt, int nodeoffset, const char *type); + +int fdt_node_is_compatible(const void *fdt, int nodeoffset, + const char *compat); +int fdt_find_compatible_node(const void *fdt, int nodeoffset, + const char *type, const char *compat);
struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset, const char *name, int *lenp); diff --git a/libfdt/fdt_ro.c b/libfdt/fdt_ro.c index 1a03109..923c389 100644 --- a/libfdt/fdt_ro.c +++ b/libfdt/fdt_ro.c @@ -51,6 +51,33 @@ static int offset_streq(const void *fdt, int offset, }
/* + * Checks if the property name matches. + */ +static int prop_name_eq(const void *fdt, int offset, const char *name, + struct fdt_property **prop, int *lenp) +{ + int namestroff, len; + + *prop = fdt_offset_ptr_typed(fdt, offset, *prop); + if (! *prop) + return -FDT_ERR_BADSTRUCTURE; + + namestroff = fdt32_to_cpu((*prop)->nameoff); + if (streq(fdt_string(fdt, namestroff), name)) { + len = fdt32_to_cpu((*prop)->len); + *prop = fdt_offset_ptr(fdt, offset, + sizeof(**prop) + len); + if (*prop) { + if (lenp) + *lenp = len; + return 1; + } else + return -FDT_ERR_BADSTRUCTURE; + } + return 0; +} + +/* * Return a pointer to the string at the given string offset. */ char *fdt_string(const void *fdt, int stroffset) @@ -59,6 +86,118 @@ char *fdt_string(const void *fdt, int stroffset) }
/* + * Check if the specified node is compatible by comparing the tokens + * in its "compatible" property with the specified string: + * + * nodeoffset - starting place of the node + * compat - the string to match to one of the tokens in the + * "compatible" list. + */ +int fdt_node_is_compatible(const void *fdt, int nodeoffset, + const char *compat) +{ + const char* cp; + int cplen, len; + + cp = fdt_getprop(fdt, nodeoffset, "compatible", &cplen); + if (cp == NULL) + return 0; + while (cplen > 0) { + if (strncmp(cp, compat, strlen(compat)) == 0) + return 1; + len = strlen(cp) + 1; + cp += len; + cplen -= len; + } + + return 0; +} + +/* + * Find a node by its device type property. On success, the offset of that + * node is returned or an error code otherwise: + * + * nodeoffset - the node to start searching from or 0, the node you pass + * will not be searched, only the next one will; typically, + * you pass 0 to start the search and then what the previous + * call returned. + * type - the device type string to match against. + */ +int fdt_find_node_by_type(const void *fdt, int nodeoffset, const char *type) +{ + int offset, nextoffset; + struct fdt_property *prop; + uint32_t tag; + int len, ret; + + CHECK_HEADER(fdt); + + tag = fdt_next_tag(fdt, nodeoffset, &nextoffset, NULL); + if (tag != FDT_BEGIN_NODE) + return -FDT_ERR_BADOFFSET; + if (nodeoffset) + nodeoffset = 0; /* start searching with next node */ + + while (1) { + offset = nextoffset; + tag = fdt_next_tag(fdt, offset, &nextoffset, NULL); + + switch (tag) { + case FDT_BEGIN_NODE: + nodeoffset = offset; + break; + + case FDT_PROP: + if (nodeoffset == 0) + break; + ret = prop_name_eq(fdt, offset, "device_type", + &prop, &len); + if (ret < 0) + return ret; + else if (ret > 0 && + strncmp(prop->data, type, len - 1) == 0) + return nodeoffset; + break; + + case FDT_END_NODE: + case FDT_NOP: + break; + + case FDT_END: + return -FDT_ERR_NOTFOUND; + + default: + return -FDT_ERR_BADSTRUCTURE; + } + } +} + +/* + * Find a node based on its device type and one of the tokens in its its + * "compatible" property. On success, the offset of that node is returned + * or an error code otherwise: + * + * nodeoffset - the node to start searching from or 0, the node you pass + * will not be searched, only the next one will; typically, + * you pass 0 to start the search and then what the previous + * call returned. + * type - the device type string to match against. + * compat - the string to match to one of the tokens in the + * "compatible" list. + */ +int fdt_find_compatible_node(const void *fdt, int nodeoffset, + const char *type, const char *compat) +{ + int offset; + + offset = fdt_find_node_by_type(fdt, nodeoffset, type); + if (offset < 0 || fdt_node_is_compatible(fdt, offset, compat)) + return offset; + + return -FDT_ERR_NOTFOUND; +} + +/* * Return the node offset of the node specified by: * parentoffset - starting place (0 to start at the root) * name - name being searched for @@ -187,7 +326,6 @@ struct fdt_property *fdt_get_property(const void *fdt, int level = 0; uint32_t tag; struct fdt_property *prop; - int namestroff; int offset, nextoffset; int err;
@@ -227,24 +365,11 @@ struct fdt_property *fdt_get_property(const void *fdt, if (level != 0) continue;
- err = -FDT_ERR_BADSTRUCTURE; - prop = fdt_offset_ptr_typed(fdt, offset, prop); - if (! prop) - goto fail; - namestroff = fdt32_to_cpu(prop->nameoff); - if (streq(fdt_string(fdt, namestroff), name)) { - /* Found it! */ - int len = fdt32_to_cpu(prop->len); - prop = fdt_offset_ptr(fdt, offset, - sizeof(*prop)+len); - if (! prop) - goto fail; - - if (lenp) - *lenp = len; - + err = prop_name_eq(fdt, offset, name, &prop, lenp); + if (err > 0) return prop; - } + else if (err < 0) + goto fail; break;
case FDT_NOP: