> -----Original Message-----
> From: Andrew Lunn <[email protected]>
> Sent: Tuesday, February 24, 2026 4:23 PM
> To: Shenwei Wang <[email protected]>
> Cc: Arnaud POULIQUEN <[email protected]>; Linus Walleij
> <[email protected]>; Bartosz Golaszewski <[email protected]>; Jonathan Corbet
> <[email protected]>; Rob Herring <[email protected]>; Krzysztof Kozlowski
> <[email protected]>; Conor Dooley <[email protected]>; Bjorn Andersson
> <[email protected]>; Mathieu Poirier <[email protected]>; Frank Li
> <[email protected]>; Sascha Hauer <[email protected]>; Shuah Khan
> <[email protected]>; [email protected]; linux-
> [email protected]; [email protected]; Pengutronix Kernel Team
> <[email protected]>; Fabio Estevam <[email protected]>; Peng Fan
> <[email protected]>; [email protected]; linux-
> [email protected]; [email protected]; linux-arm-
> [email protected]; dl-linux-imx <[email protected]>; Bartosz
> Golaszewski <[email protected]>
> Subject: Re: [EXT] Re: [PATCH v8 3/4] gpio: rpmsg: add generic rpmsg GPIO
> driver
>
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>
> > > > + remote_cm33{
> > > > + rpmsg {
> > > > + rpmsg-io-channel {
> > > > + #address-cells = <1>;
> > > > + #size-cells = <0>;
> > > > +
> > > > + gpio@0 {
> > > > + compatible = "rpmsg-gpio";
> > > > + reg = <0>;
> > > > + gpio-controller;
> > > > + #gpio-cells = <2>;
> > > > + #interrupt-cells = <2>;
> > > > + interrupt-controller;
> > > > + };
> > > > + gpio@1 {
> > > > + compatible = "rpmsg-gpio";
> > > > + reg = <1>;
> > > > + gpio-controller;
> > > > + #gpio-cells = <2>;
> > > > + #interrupt-cells = <2>;
> > > > + interrupt-controller;
> > > > + };
>
> > Then how would you distinguish gpio@0 from gpio@1 on the CM33 RPMSG bus
> in the example above?
> > They are running on the same transport.
>
> Doesn't reg indicate the channel number? gpio@0 is on rpmsg channel 0. gpio@1
> is on channel 1? The reg value gets filled into struct rpmsg_channel_info when
> the endpoints are created?
There is only a single RPMSG channel for the CM33 remoteproc in this
example-its name
is "rpmsg-io-channel". As I mentioned above, both gpio@0 and gpio@1 run over
this same transport.
The transport here is the RPMSG channel, so multiple GPIO controllers share
that channel.
Thanks,
Shenwei
>
> Andrew
