@@ -260,6 +260,33 @@ int dt_property_read_string(const struct dt_device_node *np,
return 0;
}
+int dt_property_read_string_helper(const struct dt_device_node *np,
+ const char *propname, const char **out_strs,
+ size_t sz, int skip)
+{
+ const struct dt_property *prop = dt_find_property(np, propname, NULL);
+ int l = 0, i = 0;
+ const char *p, *end;
+
+ if ( !prop )
+ return -EINVAL;
+ if ( !prop->value )
+ return -ENODATA;
+ p = prop->value;
+ end = p + prop->length;
+
+ for ( i = 0; p < end && (!out_strs || i < skip + sz); i++, p += l )
+ {
+ l = strnlen(p, end - p) + 1;
+ if ( p + l > end )
+ return -EILSEQ;
+ if ( out_strs && i >= skip )
+ *out_strs++ = p;
+ }
+ i -= skip;
+ return i <= 0 ? -ENODATA : i;
+}
+
const char *dt_property_next_string(const struct dt_property *prop,
const char *cur)
{
@@ -440,6 +440,87 @@ int dt_property_read_string(const struct dt_device_node *np,
const char *propname, const char **out_string);
/**
+ * dt_property_read_string_helper() - Utility helper for parsing string properties
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_strs: output array of string pointers.
+ * @sz: number of array elements to read.
+ * @skip: Number of strings to skip over at beginning of list.
+ *
+ * Don't call this function directly. It is a utility helper for the
+ * dt_property_read_string*() family of functions.
+ */
+int dt_property_read_string_helper(const struct dt_device_node *np,
+ const char *propname, const char **out_strs,
+ size_t sz, int skip);
+
+/**
+ * dt_property_read_string_array() - Read an array of strings from a multiple
+ * strings property.
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_strs: output array of string pointers.
+ * @sz: number of array elements to read.
+ *
+ * Search for a property in a device tree node and retrieve a list of
+ * terminated string values (pointer to data, not a copy) in that property.
+ *
+ * If @out_strs is NULL, the number of strings in the property is returned.
+ */
+static inline int dt_property_read_string_array(const struct dt_device_node *np,
+ const char *propname,
+ const char **out_strs,
+ size_t sz)
+{
+ return dt_property_read_string_helper(np, propname, out_strs, sz, 0);
+}
+
+/**
+ * dt_property_count_strings() - Find and return the number of strings from a
+ * multiple strings property.
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ *
+ * Search for a property in a device tree node and retrieve the number of null
+ * terminated string contain in it. Returns the number of strings on
+ * success, -EINVAL if the property does not exist, -ENODATA if property
+ * does not have a value, and -EILSEQ if the string is not null-terminated
+ * within the length of the property data.
+ */
+static inline int dt_property_count_strings(const struct dt_device_node *np,
+ const char *propname)
+{
+ return dt_property_read_string_helper(np, propname, NULL, 0, 0);
+}
+
+/**
+ * dt_property_read_string_index() - Find and read a string from a multiple
+ * strings property.
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @index: index of the string in the list of strings
+ * @out_string: pointer to null terminated return string, modified only if
+ * return value is 0.
+ *
+ * Search for a property in a device tree node and retrieve a null
+ * terminated string value (pointer to data, not a copy) in the list of strings
+ * contained in that property.
+ * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
+ * property does not have a value, and -EILSEQ if the string is not
+ * null-terminated within the length of the property data.
+ *
+ * The out_string pointer is modified only if a valid string can be decoded.
+ */
+static inline int dt_property_read_string_index(const struct dt_device_node *np,
+ const char *propname,
+ int index, const char **output)
+{
+ int rc = dt_property_read_string_helper(np, propname, output, 1, index);
+
+ return rc < 0 ? rc : 0;
+}
+
+/**
* dt_property_for_each_string - Iterate over an array of strings within
* a property with a given name for a given node.
*