diff options
Diffstat (limited to 'drivers/of/base.c')
| -rw-r--r-- | drivers/of/base.c | 41 |
1 files changed, 37 insertions, 4 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index c5572cb87a88..321d3ef05006 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -1091,9 +1091,10 @@ EXPORT_SYMBOL(of_parse_phandle); * To get a device_node of the `node2' node you may call this: * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args); */ -int of_parse_phandle_with_args(const struct device_node *np, const char *list_name, - const char *cells_name, int index, - struct of_phandle_args *out_args) +static int __of_parse_phandle_with_args(const struct device_node *np, + const char *list_name, + const char *cells_name, int index, + struct of_phandle_args *out_args) { const __be32 *list, *list_end; int rc = 0, size, cur_index = 0; @@ -1183,15 +1184,47 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na * Unlock node before returning result; will be one of: * -ENOENT : index is for empty phandle * -EINVAL : parsing error on data + * [1..n] : Number of phandle (count mode; when index = -1) */ - rc = -ENOENT; + rc = index < 0 ? cur_index : -ENOENT; err: if (node) of_node_put(node); return rc; } + +int of_parse_phandle_with_args(const struct device_node *np, const char *list_name, + const char *cells_name, int index, + struct of_phandle_args *out_args) +{ + if (index < 0) + return -EINVAL; + return __of_parse_phandle_with_args(np, list_name, cells_name, index, out_args); +} EXPORT_SYMBOL(of_parse_phandle_with_args); +/** + * of_count_phandle_with_args() - Find the number of phandles references in a property + * @np: pointer to a device tree node containing a list + * @list_name: property name that contains a list + * @cells_name: property name that specifies phandles' arguments count + * + * Returns the number of phandle + argument tuples within a property. It + * is a typical pattern to encode a list of phandle and variable + * arguments into a single property. The number of arguments is encoded + * by a property in the phandle-target node. For example, a gpios + * property would contain a list of GPIO specifies consisting of a + * phandle and 1 or more arguments. The number of arguments are + * determined by the #gpio-cells property in the node pointed to by the + * phandle. + */ +int of_count_phandle_with_args(const struct device_node *np, const char *list_name, + const char *cells_name) +{ + return __of_parse_phandle_with_args(np, list_name, cells_name, -1, NULL); +} +EXPORT_SYMBOL(of_count_phandle_with_args); + #if defined(CONFIG_OF_DYNAMIC) static int of_property_notify(int action, struct device_node *np, struct property *prop) |