diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/of/base.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index 9d005072a5f6..1ea95e3eb02b 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -904,6 +904,38 @@ struct device_node *of_find_node_by_phandle(phandle handle) EXPORT_SYMBOL(of_find_node_by_phandle); /** + * of_property_count_elems_of_size - Count the number of elements in a property + * + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @elem_size: size of the individual element + * + * Search for a property in a device node and count the number of elements of + * size elem_size in it. Returns number of elements on sucess, -EINVAL if the + * property does not exist or its length does not match a multiple of elem_size + * and -ENODATA if the property does not have a value. + */ +int of_property_count_elems_of_size(const struct device_node *np, + const char *propname, int elem_size) +{ + struct property *prop = of_find_property(np, propname, NULL); + + if (!prop) + return -EINVAL; + if (!prop->value) + return -ENODATA; + + if (prop->length % elem_size != 0) { + pr_err("size of %s in node %s is not a multiple of %d\n", + propname, np->full_name, elem_size); + return -EINVAL; + } + + return prop->length / elem_size; +} +EXPORT_SYMBOL_GPL(of_property_count_elems_of_size); + +/** * of_find_property_value_of_size * * @np: device node from which the property value is to be read. |