Message ID | 20200418170703.1583-2-digetx@gmail.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | Support DRM bridges on NVIDIA Tegra | expand |
On Sat, 18 Apr 2020 20:06:58 +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 the graph. > > This patch adds of_graph_get_local_port() which returns pointer to a local > port node, or NULL if graph isn't specified in a device-tree for a given > device node. > > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/of/property.c | 32 +++++++++++++++++++++++--------- > include/linux/of_graph.h | 7 +++++++ > 2 files changed, 30 insertions(+), 9 deletions(-) > Reviewed-by: Rob Herring <robh@kernel.org>
Hi Dmitry On Sat, Apr 18, 2020 at 08:06:58PM +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 the graph. > > This patch adds of_graph_get_local_port() which returns pointer to a local > port node, or NULL if graph isn't specified in a device-tree for a given > device node. > > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Nice little helper function. Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Rob - OK to commit to drm-misc-next? Sam > --- > drivers/of/property.c | 32 +++++++++++++++++++++++--------- > include/linux/of_graph.h | 7 +++++++ > 2 files changed, 30 insertions(+), 9 deletions(-) > > diff --git a/drivers/of/property.c b/drivers/of/property.c > index 252e4f600155..5dbeccaabb86 100644 > --- a/drivers/of/property.c > +++ b/drivers/of/property.c > @@ -608,15 +608,7 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent, > * parent port node. > */ > if (!prev) { > - struct device_node *node; > - > - node = of_get_child_by_name(parent, "ports"); > - if (node) > - parent = node; > - > - port = of_get_child_by_name(parent, "port"); > - of_node_put(node); > - > + port = of_graph_get_local_port(parent); > if (!port) { > pr_err("graph: no port node found in %pOF\n", parent); > return NULL; > @@ -765,6 +757,28 @@ struct device_node *of_graph_get_remote_port(const struct device_node *node) > } > EXPORT_SYMBOL(of_graph_get_remote_port); > > +/** > + * of_graph_get_local_port() - get 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. > + */ > +struct device_node *of_graph_get_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; > +} > +EXPORT_SYMBOL(of_graph_get_local_port); > + > int of_graph_get_endpoint_count(const struct device_node *np) > { > struct device_node *endpoint; > diff --git a/include/linux/of_graph.h b/include/linux/of_graph.h > index 01038a6aade0..1fdeb72c7765 100644 > --- a/include/linux/of_graph.h > +++ b/include/linux/of_graph.h > @@ -54,6 +54,7 @@ struct device_node *of_graph_get_remote_port_parent( > struct device_node *of_graph_get_remote_port(const struct device_node *node); > struct device_node *of_graph_get_remote_node(const struct device_node *node, > u32 port, u32 endpoint); > +struct device_node *of_graph_get_local_port(const struct device_node *node); > #else > > static inline int of_graph_parse_endpoint(const struct device_node *node, > @@ -116,6 +117,12 @@ static inline struct device_node *of_graph_get_remote_node( > return NULL; > } > > +static inline struct device_node *of_graph_get_local_port( > + const struct device_node *node) > +{ > + return NULL; > +} > + > #endif /* CONFIG_OF */ > > #endif /* __LINUX_OF_GRAPH_H */ > -- > 2.26.0 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
On Wed, May 6, 2020 at 11:32 AM Sam Ravnborg <sam@ravnborg.org> wrote: > > Hi Dmitry > > On Sat, Apr 18, 2020 at 08:06:58PM +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 the graph. > > > > This patch adds of_graph_get_local_port() which returns pointer to a local > > port node, or NULL if graph isn't specified in a device-tree for a given > > device node. > > > > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > Nice little helper function. > Reviewed-by: Sam Ravnborg <sam@ravnborg.org> > > Rob - OK to commit to drm-misc-next? Yes, that's why I gave my R-by. Rob
diff --git a/drivers/of/property.c b/drivers/of/property.c index 252e4f600155..5dbeccaabb86 100644 --- a/drivers/of/property.c +++ b/drivers/of/property.c @@ -608,15 +608,7 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent, * parent port node. */ if (!prev) { - struct device_node *node; - - node = of_get_child_by_name(parent, "ports"); - if (node) - parent = node; - - port = of_get_child_by_name(parent, "port"); - of_node_put(node); - + port = of_graph_get_local_port(parent); if (!port) { pr_err("graph: no port node found in %pOF\n", parent); return NULL; @@ -765,6 +757,28 @@ struct device_node *of_graph_get_remote_port(const struct device_node *node) } EXPORT_SYMBOL(of_graph_get_remote_port); +/** + * of_graph_get_local_port() - get 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. + */ +struct device_node *of_graph_get_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; +} +EXPORT_SYMBOL(of_graph_get_local_port); + int of_graph_get_endpoint_count(const struct device_node *np) { struct device_node *endpoint; diff --git a/include/linux/of_graph.h b/include/linux/of_graph.h index 01038a6aade0..1fdeb72c7765 100644 --- a/include/linux/of_graph.h +++ b/include/linux/of_graph.h @@ -54,6 +54,7 @@ struct device_node *of_graph_get_remote_port_parent( struct device_node *of_graph_get_remote_port(const struct device_node *node); struct device_node *of_graph_get_remote_node(const struct device_node *node, u32 port, u32 endpoint); +struct device_node *of_graph_get_local_port(const struct device_node *node); #else static inline int of_graph_parse_endpoint(const struct device_node *node, @@ -116,6 +117,12 @@ static inline struct device_node *of_graph_get_remote_node( return NULL; } +static inline struct device_node *of_graph_get_local_port( + const struct device_node *node) +{ + return NULL; +} + #endif /* CONFIG_OF */ #endif /* __LINUX_OF_GRAPH_H */
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 the graph. This patch adds of_graph_get_local_port() which returns pointer to a local port node, or NULL if graph isn't specified in a device-tree for a given device node. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> --- drivers/of/property.c | 32 +++++++++++++++++++++++--------- include/linux/of_graph.h | 7 +++++++ 2 files changed, 30 insertions(+), 9 deletions(-)