From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCH v4 04/11] device property: Add functions for accessing node's parents Date: Mon, 2 Sep 2019 15:46:16 +0300 Message-ID: <20190902124616.GH2680@smile.fi.intel.com> References: <20190902083240.20367-1-sakari.ailus@linux.intel.com> <20190902083240.20367-5-sakari.ailus@linux.intel.com> <20190902101426.GB2680@smile.fi.intel.com> <20190902123431.GK5475@paasikivi.fi.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20190902123431.GK5475@paasikivi.fi.intel.com> Sender: linux-kernel-owner@vger.kernel.org To: Sakari Ailus Cc: Petr Mladek , linux-kernel@vger.kernel.org, rafael@kernel.org, linux-acpi@vger.kernel.org, devicetree@vger.kernel.org, Rob Herring , Heikki Krogerus List-Id: devicetree@vger.kernel.org On Mon, Sep 02, 2019 at 03:34:31PM +0300, Sakari Ailus wrote: > Hi Andy, > > On Mon, Sep 02, 2019 at 01:14:26PM +0300, Andy Shevchenko wrote: > > On Mon, Sep 02, 2019 at 11:32:33AM +0300, Sakari Ailus wrote: > > > Add two convenience functions for accessing node's parents: > > > > > > fwnode_count_parents() returns the number of parent nodes a given node > > > has. fwnode_get_nth_parent() returns node's parent at a given distance > > > from the node itself. > > > > > > > Much better now, thanks! > > > > Reviewed-by: Andy Shevchenko > > > > though one question below. > > > +/** > > > + * fwnode_get_nth_parent - Return an nth parent of a node > > > + * @fwnode: The node the parent of which is requested > > > + * @depth: Distance of the parent from the node > > > + * > > > + * Returns the nth parent of a node. If @depth is 0, the functionality is > > > + * equivalent to fwnode_handle_get(). For @depth == 1, it is fwnode_get_parent() > > > + * and so on. > > > + * > > > + * The caller is responsible for calling fwnode_handle_put() for the returned > > > + * node. > > > + */ > > > +struct fwnode_handle *fwnode_get_nth_parent(struct fwnode_handle *fwnode, > > > + unsigned int depth) > > > +{ > > > + unsigned int i; > > > + > > > + fwnode_handle_get(fwnode); > > > + > > > + for (i = 0; i < depth && fwnode; i++) > > > + fwnode = fwnode_get_next_parent(fwnode); > > > + > > > > If 'fnode == NULL' and 'i < depth', shan't we return some kind of error? > > How about adding to the comment, after the first sentence of the > description: > > If there is no parent at the requested depth, NULL is returned. Works for me! -- With Best Regards, Andy Shevchenko