Re: [PATCH v2 0/7] of: property: Make fw_devlink follow GPIO, PWM and clock nexus maps

[Frieder Schrempf]

Hi Ernest,

On 10.09.26 16:16, Ernest Van Hoecke wrote:
> This series fixes an fw_devlink supplier-resolution problem reported by
> Leonardo Costa while using a Devicetree nexus to describe GPIO and PWM
> resources routed through an LVDS connector. Consumers referencing the
> nexus could remain deferred because fw_devlink linked them to the nexus
> rather than to the providers selected by gpio-map and pwm-map. [1]
> 
> GPIO, PWM and clock consumer APIs use of_parse_phandle_with_args_map()
> to resolve specifiers through gpio-map, pwm-map and clock-map
> properties. The corresponding fw_devlink parsers use direct phandle
> parsing instead. Given a consumer which references a nexus, the consumer
> API and fw_devlink therefore resolve the reference to different nodes:
> 
>   consumer API:  consumer -> nexus -> mapped provider
>   fw_devlink:    consumer -> nexus
> 
> A nexus is a translation node rather than the resource provider and need
> not have a driver. The link to it can consequently remain unresolved and
> defer the consumer even though the mapped provider is available.
> 
> Make the fw_devlink GPIO, PWM and clock parsers use the same map-aware
> resolver as their consumer APIs. The resolver also handles valid direct
> references by returning the original provider when no map is present.
> Use dedicated exact-name and suffix declaration macros to opt these
> bindings into map-aware parsing without changing unrelated property
> parsers. Retain GPIO's existing exclusions and compatibility handling.
> 
> The regression tests call the OF add_links operation and verify that a
> mapped reference creates exactly one link to the final provider, not to
> the nexus. They also cover valid direct references. The GPIO tests
> exercise all property spellings recognized by fw_devlink, including the
> deprecated singular and unprefixed forms.
> 
> Tested with:
>   - The new CONFIG_OF_UNITTEST fw_devlink cases under QEMU/x86_64 all
>     passed
>   - W=1 builds on x86_64 and arm64, including the OF unittest data
>   - Toradex Verdin iMX8M Plus hardware using a connector nexus for the
>     display GPIO and PWM resources: the display probes successfully
> 
> [1] https://lore.kernel.org/all/juuc4af7ndbajcl7gzf4tg5qz2q2j5tt3rvql4jbauradujrre@gc5nbdhhixaf/
> 
> Signed-off-by: Ernest Van Hoecke <ernest.vanhoecke@xxxxxxxxxxx>
What is the status of this? Can you send a follow-up?

Frank is asking me to use nexus connector nodes and it looks like I will
run into this issue.

Thanks
Frieder