On Mon, Jan 29, 2024 at 02:29:22PM +0200, Tomi Valkeinen wrote: > On 29/01/2024 02:54, Kuninori Morimoto wrote: > > We already have of_graph_get_next_endpoint(), but it is not intuitive > > to use. > > > > (X) node { > > (Y) ports { > > port@0 { endpoint { remote-endpoint = ...; };}; > > (A1) port@1 { endpoint { remote-endpoint = ...; }; > > (A2) endpoint { remote-endpoint = ...; };}; > > (B) port@2 { endpoint { remote-endpoint = ...; };}; > > }; > > }; > > > > For example, if I want to handle port@1's 2 endpoints (= A1, A2), > > I want to use like below > > > > A1 = of_graph_get_next_endpoint(port1, NULL); > > A2 = of_graph_get_next_endpoint(port1, A1); > > > > But 1st one will be error, because of_graph_get_next_endpoint() requested > > "parent" means "node" (X) or "ports" (Y), not "port". > > Below are OK > > > > of_graph_get_next_endpoint(node, NULL); // node/ports/port@0/endpoint > > of_graph_get_next_endpoint(ports, NULL); // node/ports/port@0/endpoint > > > > In other words, we can't handle A1/A2 directly via > > of_graph_get_next_endpoint() so far. > > > > There is another non intuitive behavior on of_graph_get_next_endpoint(). > > In case of if I could get A1 pointer for some way, and if I want to > > handle port@1 things, I would like use it like below > > > > /* > > * "endpoint" is now A1, and handle port1 things here, > > * but we don't know how many endpoints port1 has. > > * > > * Because "endpoint" is non NULL, we can use port1 > > * as of_graph_get_next_endpoint(port1, xxx) > > */ > > do { > > /* do something for port1 specific things here */ > > } while (endpoint = of_graph_get_next_endpoint(port1, endpoint)) > > > > But it also not worked as I expected. > > I expect it will be A1 -> A2 -> NULL, > > but it will be A1 -> A2 -> B, because of_graph_get_next_endpoint() > > will fetch endpoint beyond the port. > > > > It is not useful on generic driver like Generic Sound Card. > > It uses of_get_next_child() instead for now, but it is not intuitive, > > and not check node name (= "endpoint"). > > > > To handle endpoint more intuitive, create of_graph_get_next_endpoint_raw() > > > > of_graph_get_next_endpoint_raw(port1, NULL); // A1 > > of_graph_get_next_endpoint_raw(port1, A1); // A2 > > of_graph_get_next_endpoint_raw(port1, A2); // NULL > > > > Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx> > > --- > > drivers/of/property.c | 26 +++++++++++++++++++++++++- > > include/linux/of_graph.h | 2 ++ > > 2 files changed, 27 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/of/property.c b/drivers/of/property.c > > index 14ffd199c9b1..37dbb1b0e742 100644 > > --- a/drivers/of/property.c > > +++ b/drivers/of/property.c > > @@ -667,6 +667,30 @@ struct device_node *of_graph_get_next_port(const struct device_node *parent, > > } > > EXPORT_SYMBOL(of_graph_get_next_port); > > > > +/** > > + * of_graph_get_next_endpoint_raw() - get next endpoint node > > How about "of_graph_get_next_port_endpoint()"? We may want to also rename the existing of_graph_get_next_endpoint() function to of_graph_next_dev_endpoint() then. It would be a tree-wide patch, which is always annoying to get reviewed and merged, so if Rob would prefer avoiding the rename, I'm fine with that. > > + * @port: pointer to the target port node > > + * @endpoint: current endpoint node, or NULL to get first > > + * > > + * Return: An 'endpoint' node pointer with refcount incremented. Refcount > > + * of the passed @prev node is decremented. > > + */ > > It might be good to highlight here the difference to the > of_graph_get_next_endpoint(). Yes, and the documentation of of_graph_get_next_endpoint() shoul also be improved. > > +struct device_node *of_graph_get_next_endpoint_raw(const struct device_node *port, > > + struct device_node *endpoint) > > +{ > > + if (!port) > > + return NULL; > > + > > + do { > > + endpoint = of_get_next_child(port, endpoint); > > + if (!endpoint) > > + break; > > + } while (!of_node_name_eq(endpoint, "endpoint")); > > + > > + return endpoint; > > +} > > +EXPORT_SYMBOL(of_graph_get_next_endpoint_raw); > > + > > /** > > * of_graph_get_next_endpoint() - get next endpoint node > > * @parent: pointer to the parent device node > > @@ -708,7 +732,7 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent, > > * getting the next child. If the previous endpoint is NULL this > > * will return the first child. > > */ > > - endpoint = of_get_next_child(port, prev); > > + endpoint = of_graph_get_next_endpoint_raw(port, prev); > > if (endpoint) { > > of_node_put(port); > > return endpoint; > > diff --git a/include/linux/of_graph.h b/include/linux/of_graph.h > > index fff598640e93..427905a6e8c3 100644 > > --- a/include/linux/of_graph.h > > +++ b/include/linux/of_graph.h > > @@ -57,6 +57,8 @@ int of_graph_get_port_count(const struct device_node *np); > > struct device_node *of_graph_get_port_by_id(struct device_node *node, u32 id); > > struct device_node *of_graph_get_next_endpoint(const struct device_node *parent, > > struct device_node *previous); > > +struct device_node *of_graph_get_next_endpoint_raw(const struct device_node *port, > > + struct device_node *prev); > > struct device_node *of_graph_get_next_port(const struct device_node *parent, > > struct device_node *previous); > > struct device_node *of_graph_get_endpoint_by_regs( -- Regards, Laurent Pinchart