Re: [PATCH 1/3] dt-bindings: rtc: Add Raspberry Pi 5 RTC binding

 >Whether device has separate node, depends on it having dedicated
 >resources. I don't see such here, so unlikely it should have a node in
 >the first place (see writing bindings or DTS101 where exactly this
 >question is asked).

I think you are right there is no extra node needed (only 
the trickle-voltage-millivolt property) and it could move directly into 
the rpi_firmware node without creating an extra node.

Kind regards
Sander

On 9/10/26 09:08, Krzysztof Kozlowski wrote:

On 09/09/2026 22:24, Sander Speetjens wrote:

quoted

Thanks for your response

quoted

And more important, where is any interface to actually control the RTC?
I see nothing, so your firmware is? Then this is not a separate device
and you just added DTS for your driver, which is a no go (see writing
bindings).

The RTC is a physical, battery-backed RTC, but the Raspberry Pi firmware
exposes its register interface exclusively through the firmware mailbox.
I initially used a firmware phandle so the RTC driver could obtain the
existing rpi_firmware instance.

Based on your comment, I think it is more appropriate to model
the RTC as a child device of rpi-firmware,
referencing to the existing firmware clock/reset/power services,
and have the driver obtain the firmware interface from its parent
rather than adding a phandle solely for driver plumbing.
Which also means moving this to arm/bcm/raspberrypi,bcm2835-firmware.yaml

Whether device has separate node, depends on it having dedicated
resources. I don't see such here, so unlikely it should have a node in
the first place (see writing bindings or DTS101 where exactly this
question is asked).

Best regards,
Krzysztof