Re: [PATCH] mfd: syscon: Fix syscon name for device tree

From: Tony Lindgren
Date: Tue Jan 08 2019 - 10:38:44 EST


* JeffyChen <jeffy.chen@xxxxxxxxxxxxxx> [190108 03:17]:
> Hi Tony,
>
> On 01/08/2019 08:15 AM, Tony Lindgren wrote:
> > * Tony Lindgren <tony@xxxxxxxxxxx> [190108 00:06]:
> > > I'm now seeing the following error on omap5 during boot:
> > >
> > > (NULL device *): Failed to create dummy-scm_conf@0 debugfs directory
> This log means failed to init regmap debugfs with device(NULL) and
> name("scm_conf@0"), which likely to be called from of_syscon_register() with
> np fullname("scm_conf@0").
>
> So my guess would be there're more than one syscon dts nodes named
> "scm_conf@0".

Yup.

> For omap5 and scm_conf@0, should be these 2:
> https://elixir.bootlin.com/linux/latest/source/arch/arm/boot/dts/omap5.dtsi#L167
> scm_conf: scm_conf@0 {
> compatible = "syscon";
>
> https://elixir.bootlin.com/linux/latest/source/arch/arm/boot/dts/omap5.dtsi#L313
> scm_wkup_pad_conf: scm_conf@0 {
> compatible = "syscon", "simple-bus";

Yes those are the one.

> Maybe try to rename one of them(for example, rename the second one to
> "scm_wkup_pad_conf@0").

Well the thing is that any valid node name should work here
just like it does for devices. In this case the syscon
instances are on separate inteconnect instances. So it seems
that we should do something similar to what we already do in
of_device_make_bus_id().

BTW, I was trying to patch the wrong function :) The right
function to fix is of_syscon_register() for the dts case.

Regards,

Tony