dt: add helper function to read u32 arrays

Rework of_property_read_u32 to read an array of values. Then
of_property_read_u32 becomes an inline with array size of 1.

Also make struct device_node ptr const.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 13 insertions, 6 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 57ec27b..02ed367 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -596,32 +596,39 @@ struct device_node *of_find_node_by_phandle(phandle handle)
 EXPORT_SYMBOL(of_find_node_by_phandle);
 
 /**
- * of_property_read_u32 - Find and read a 32 bit integer from a property
+ * of_property_read_u32_array - Find and read an array of 32 bit integers
+ * from a property.
+ *
  * @np:		device node from which the property value is to be read.
  * @propname:	name of the property to be searched.
  * @out_value:	pointer to return value, modified only if return value is 0.
  *
- * Search for a property in a device node and read a 32-bit value from
+ * Search for a property in a device node and read 32-bit value(s) from
  * it. Returns 0 on success, -EINVAL if the property does not exist,
  * -ENODATA if property does not have a value, and -EOVERFLOW if the
  * property data isn't large enough.
  *
  * The out_value is modified only if a valid u32 value can be decoded.
  */
-int of_property_read_u32(struct device_node *np, char *propname, u32 *out_value)
+int of_property_read_u32_array(const struct device_node *np, char *propname,
+			       u32 *out_values, size_t sz)
 {
 	struct property *prop = of_find_property(np, propname, NULL);
+	const __be32 *val;
 
 	if (!prop)
 		return -EINVAL;
 	if (!prop->value)
 		return -ENODATA;
-	if (sizeof(*out_value) > prop->length)
+	if ((sz * sizeof(*out_values)) > prop->length)
 		return -EOVERFLOW;
-	*out_value = be32_to_cpup(prop->value);
+
+	val = prop->value;
+	while (sz--)
+		*out_values++ = be32_to_cpup(val++);
 	return 0;
 }
-EXPORT_SYMBOL_GPL(of_property_read_u32);
+EXPORT_SYMBOL_GPL(of_property_read_u32_array);
 
 /**
  * of_property_read_string - Find and read a string from a property