Hi all,
This is a gentle ping with David and the DT maintainers in Cc: (I am not
sure what the protocol is here, so I'll simply give this a try).
On 5/22/24 16:32, Michael Riesch wrote:
> In device tree overlays, the following patterns occur frequently:
>
> board.dts:
> /dts-v1/;
>
> / {
> display-controller {
> ports {
> #address-cells = <1>;
> #size-cells = <0>;
>
> vp0: port@0 {
> reg = <0>;
>
> vp0_out: endpoint {
> };
> };
>
> vp1: port@1 {
> reg = <1>;
> };
> };
> };
> };
>
> overlay-endpoint.dtso:
> /dts-v1/;
> /plugin/;
>
> &{/} {
> hdmi-tx-connector {
> port {
> hdmi_tx_in: endpoint {
> remote-endpoint = <&vp0_out>;
> };
> };
> };
> };
>
> &vp0_out {
> remote-endpoint = <&hdmi_tx_in>;
> };
>
> In this case, dtc expects that the node referenced by &vp0_out is
> named "endpoint", but the name cannot be inferred. Also, dtc
> complains about the connections between the endpoints not being
> bidirectional.
>
> Similarly, for a different overlay overlay-port.dtso:
> /dts-v1/;
> /plugin/;
>
> &{/} {
> panel {
> port {
> panel_in: endpoint {
> remote-endpoint = <&vp1_out>;
> };
> };
> };
> };
>
> &vp1 {
> vp1_out: endpoint {
> remote-endpoint = <&panel_in>;
> };
> };
>
> dtc expects that the node referenced by &vp1 is named "port", but the
> name cannot be inferred.
>
> Relax the corresponding checks and skip the parts that are not reasonable
> for device tree overlays.
>
> Cc: Heiko Stuebner <heiko@xxxxxxxxx>
> Signed-off-by: Michael Riesch <michael.riesch@xxxxxxxxxxxxxx>
> ---
> Habidere,
>
> This patch fixes several warnings
> - Warning (graph_port): /fragment@3: graph port node name should be
> 'port'
> - Warning (graph_endpoint): /fragment@3/__overlay__: graph endpoint
> node name should be 'endpoint'
> - Warning (graph_endpoint): /fragment@3/__overlay__: graph connection
> to node '/fragment@2/__overlay__/.../port/endpoint' is not
> bidirectional
> that appear when compiling device tree overlays.
>
> This first warning popped up e.g., in the scope of [1], [2]. The latter
> two warnings appear regularly when compiling our downstream overlays. As
> we plan to submit them to mainline soon, we'll hit that blocker sooner or
> later.
>
> Looking forward to your comments!
>
> Link: https://lore.kernel.org/lkml/20240412-feature-wolfvision-pf5-display-v1-1-f032f32dba1a@xxxxxxxxxxxxxx/ [1]
> Link: https://lore.kernel.org/lkml/20240423082941.2626102-1-heiko@xxxxxxxxx/T/ [2]
Feedback on this issue would be most welcome!
Thanks a lot and best regards,
Michael
> ---
> checks.c | 16 ++++++++++++----
> 1 file changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/checks.c b/checks.c
> index 2fb7ee5..2ea5913 100644
> --- a/checks.c
> +++ b/checks.c
> @@ -1822,10 +1822,14 @@ static void check_graph_port(struct check *c, struct dt_info *dti,
> if (node->bus != &graph_port_bus)
> return;
>
> + check_graph_reg(c, dti, node);
> +
> + /* skip checks below for overlays */
> + if (dti->dtsflags & DTSF_PLUGIN)
> + return;
> +
> if (!strprefixeq(node->name, node->basenamelen, "port"))
> FAIL(c, dti, node, "graph port node name should be 'port'");
> -
> - check_graph_reg(c, dti, node);
> }
> WARNING(graph_port, check_graph_port, NULL, &graph_nodes);
>
> @@ -1860,11 +1864,15 @@ static void check_graph_endpoint(struct check *c, struct dt_info *dti,
> if (!node->parent || node->parent->bus != &graph_port_bus)
> return;
>
> + check_graph_reg(c, dti, node);
> +
> + /* skip checks below for overlays */
> + if (dti->dtsflags & DTSF_PLUGIN)
> + return;
> +
> if (!strprefixeq(node->name, node->basenamelen, "endpoint"))
> FAIL(c, dti, node, "graph endpoint node name should be 'endpoint'");
>
> - check_graph_reg(c, dti, node);
> -
> remote_node = get_remote_endpoint(c, dti, node);
> if (!remote_node)
> return;
>
> ---
> base-commit: ae26223a056e040b2d812202283d47c6e034d063
> change-id: 20240522-bugfix-relax-checks-for-overlays-e72b11df44a1
>
> Best regards,
