[PATCH v2 0/4] regulator: spacemit-p1: Fix voltage ranges and support board power tree

Guodong Xu guodong at riscstar.com
Sat Jan 24 20:18:23 PST 2026


On Sat, Jan 24, 2026 at 2:25 PM Vivian Wang <wangruikang at iscas.ac.cn> wrote:
>
>
> On 1/24/26 08:20, Guodong Xu wrote:
> > [...]
> >
> > Note: Patch 3 introduces a bisect breakage by transitioning to
> > pin-specific supply names. Probe failures will occur on existing boards
> > until Patch 4 updates the corresponding DTS file.
>
> Ouch, that's not a bisect breakage, that's an *ABI breakage*. And AFAICT
> this is still not okay in 2026,
> see Documentation/devicetree/bindings/ABI.rst
>
> So the bindings would need to be changed to accept both the new and old way.

Ideally yes. However, considering this ABI change's actual effect, the two
K1 boards (BPI-F3 and Jupiter) in the kernel get their power settings
from boot firmware as well, and the types of peripherals enabled in the .dts
files are very limited, the probe failure of the pmic regulator doesn't
affect much. So, I think this breakage is acceptable.

>
> Driver-wise, at a cursory look from someone not familiar with the
> regulator stuff, maybe we can make it compatible with old DTS by adding
> the new names as aliases ({devm_,}regulator_register_supply_alias?) as
> "vin" or "buck5", if we see the old vin-supply definitions?
>

We can do that of course. My hesitation is, however, it makes the driver take
extra code which may not be needed once all .dts files have been updated. The
driver code will be left there forever.

BR,
Guodong Xu



More information about the linux-riscv mailing list