dt: add 'const' for of_property_read_string parameter **out_string

The existing dt codes usually call of_get_property to get a string
property and save it as a 'const char *'.  The patch adds'const' for
of_property_read_string parameter **out_string to make the converting
of existing code a little easier.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

diff --git a/drivers/of/base.c b/drivers/of/base.c
index b8b65fddbeb5979a668c705f5878724bcec519be..57ec27bed44f1fbcf6ebb8857a02187008c5289e 100644 (file)
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -639,7 +639,7 @@ EXPORT_SYMBOL_GPL(of_property_read_u32);
  * The out_string pointer is modified only if a valid string can be decoded.
  */
 int of_property_read_string(struct device_node *np, char *propname,
-                               char **out_string)
+                               const char **out_string)
 {
        struct property *prop = of_find_property(np, propname, NULL);
        if (!prop)

diff --git a/include/linux/of.h b/include/linux/of.h
index 4fc4c1b8d5d59e6617c9109489ff9bad5c91d787..b23852002b30022d93ce2ec5050dd45c55483ae4 100644 (file)
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -198,7 +198,7 @@ extern struct property *of_find_property(const struct device_node *np,
 extern int of_property_read_u32(struct device_node *np, char *propname,
                                        u32 *out_value);
 extern int of_property_read_string(struct device_node *np, char *propname,
-                                       char **out_string);
+                                       const char **out_string);
 extern int of_device_is_compatible(const struct device_node *device,
                                   const char *);
 extern int of_device_is_available(const struct device_node *device);