dt: add helper function to read u32 arrays

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

extern struct property *of_find_property(const struct device_node *np,

					 const char *name,

					 int *lenp);

extern int of_property_read_u32(struct device_node *np, char *propname,

					u32 *out_value);

extern int of_property_read_u32_array(const struct device_node *np,

				      char *propname,

				      u32 *out_values,

				      size_t sz);

static inline int of_property_read_u32(const struct device_node *np,

				       char *propname,

				       u32 *out_value)

{

	return of_property_read_u32_array(np, propname, out_value, 1);

}

extern int of_property_read_string(struct device_node *np, char *propname,

					const char **out_string);

extern int of_device_is_compatible(const struct device_node *device,