[PATCH 2/5] regulator: dt-bindings: mt6359: Drop bogus vcn33_[12]_* split regulators

[Chen-Yu Tsai]

On Mon, Mar 23, 2026 at 4:31 PM Krzysztof Kozlowski <krzk at kernel.org> wrote:
>
> On 23/03/2026 09:26, Chen-Yu Tsai wrote:
> > On Fri, Mar 20, 2026 at 5:54 PM Krzysztof Kozlowski <krzk at kernel.org> wrote:
> >>
> >> On Fri, Mar 20, 2026 at 03:24:35PM +0800, Chen-Yu Tsai wrote:
> >>> vcn33_[12]_bt and vcn33_[12]_wifi refer to the same output. There are
> >>> two enable bits in the registers so that BT and WiFi drivers can toggle
> >>> them separately without any coordination. If either bit is set, then the
> >>> regulator output is enabled.
> >>>
> >>> Unfortunately some of them are already referenced by in-tree device
> >>> trees. To keep backward compatibility with them, keep the vcn33_*_bt
> >>
> >> So you drop "_wifi" regulators breaking the ABI, no?
> >
> > Indeed it is a breakage. I kept the *_bt part to cover all in-tree
> > device trees.
> >
> > But the representation itself is broken, as explained in the commit
> > message.
> >
> > I leave it to the platform maintainers to decide whether this "breakage"
> > to fix the broken representation is acceptable.
> >
> > Note that there is a similar issue with the *_sshub and non _sshub
> > regulators: there is only one actual output for the two. I'm still
> > asking the vendor for hardware behavior specifics.
> >
> >>> regulator. Also combine them for a shorten regular expression pattern.
> >>
> >> Instead the duplicates should be deprecated and driver should still
> >> support the "_wifi" variants.
> >
> > But it doesn't really work in the driver. You cannot set different
> > constraints on the two, especially conflicting constraints, and expect
> > them to work. And if you set the voltage on one of them, the other
> > will change as well.
>
> Of course, but now imagine a DTB with only *_wifi regulators and no *_bt.
>
> >
> > If we want the driver to support both with _sane_ behavior, we would
> > need to introduce some sort of alias lookup for both reading
> > constraints and resolving supplies. The driver registers _just_ one
> > regulator, and both DT nodes resolve to it.
>
> Yes, either alias lookup or adjusting the regulator_desc before
> registering them, depending on the nodes.
>
> If I understood old code correctly, the point is that ABI allowed *_wifi
> without *_bt and this would be a working setup. Now it won't work.

OK. I will drop this part for now and just add the supplies. I'll
resend the cleanup once I figure out how to do it in the regulator
driver.

ChenYu