On Thu, Dec 26, 2013 at 13:18 +0800, Xiubo Li wrote: > > --- a/include/linux/of.h > +++ b/include/linux/of.h > @@ -601,6 +601,23 @@ static inline int of_property_read_u32(const struct device_node *np, > return of_property_read_u32_array(np, propname, out_value, 1); > } > > +/** > + * of_property_optional - Find one optional property > + * @np: device node from which the property to be searched. > + * @propname: name of the optional property to be searched for. > + * > + * Get to know whether one optional property is present or not in a > + * device node. > + * Returns true if the property is present, false otherwise. > + */ > +static inline bool of_property_optional(const struct device_node *np, > + const char *propname) > +{ > + struct property *prop = of_find_property(np, propname, NULL); > + > + return prop ? true : false; > +} > + Exactly how is this different from of_property_read_bool()? AFAICS it's identical! You may be trying to solve the wrong problem. And I'm afraid that the routine's name you picked is even more confusing. The call site ("if (of_property_optional() ...") will no longer reflect that it's evaluating a boolean condition. Being an optional property and being boolean are two completely different things. virtually yours Gerhard Sittig -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr. 5, D-82194 Groebenzell, Germany Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: office@xxxxxxx -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html