From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [PATCH v8 1/7] of_graph: add of_graph_presents() Date: Mon, 29 Jun 2020 17:12:11 -0600 Message-ID: <20200629231211.GA3142766@bogus> References: <20200617222703.17080-1-digetx@gmail.com> <20200617222703.17080-2-digetx@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20200617222703.17080-2-digetx-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Dmitry Osipenko Cc: Thierry Reding , Sam Ravnborg , Laurent Pinchart , Frank Rowand , dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-tegra@vger.kernel.org On Thu, Jun 18, 2020 at 01:26:57AM +0300, Dmitry Osipenko wrote: > In some case, like a DRM display code for example, it's useful to silently > check whether port node exists at all in a device-tree before proceeding > with parsing of the graph. > > This patch adds of_graph_presents() that returns true if given device-tree > node contains OF graph port. > > Signed-off-by: Dmitry Osipenko > --- > drivers/of/property.c | 52 +++++++++++++++++++++++++++++++++------- > include/linux/of_graph.h | 6 +++++ > 2 files changed, 49 insertions(+), 9 deletions(-) > > diff --git a/drivers/of/property.c b/drivers/of/property.c > index 1f2086f4e7ce..b84ed6a7cf50 100644 > --- a/drivers/of/property.c > +++ b/drivers/of/property.c > @@ -29,6 +29,48 @@ > > #include "of_private.h" > > +/** > + * of_graph_get_first_local_port() - get first local port node > + * @node: pointer to a local endpoint device_node > + * > + * Return: First local port node associated with local endpoint node linked > + * to @node. Use of_node_put() on it when done. > + */ > +static struct device_node * > +of_graph_get_first_local_port(const struct device_node *node) > +{ > + struct device_node *ports, *port; > + > + ports = of_get_child_by_name(node, "ports"); > + if (ports) > + node = ports; > + > + port = of_get_child_by_name(node, "port"); > + of_node_put(ports); > + > + return port; > +} > + > +/** > + * of_graph_presents() - check graph's presence > + * @node: pointer to a device_node checked for the graph's presence > + * > + * Return: True if @node has a port or ports sub-node, false otherwise. > + */ > +bool of_graph_presents(const struct device_node *node) of_graph_is_present Otherwise, Reviewed-by: Rob Herring