Re: [PATCH 0/5] power: supply: Fix probe time race against driver teardown and battery parsing

[Alexey Charkov]

On Mon, Sep 7, 2026 at 7:01 PM Alexey Charkov <alchark@xxxxxxxxxxx> wrote:
>
> If a bus holding the battery-equipped power supply goes down right after
> it registered, it leads to massive fireworks as the driver starts to tear
> down its resources while callers from other contexts are already eager to
> process events using this driver's callbacks (and their private data).
>
> In current power supply core it's further aggravated by the fact that the
> battery parsing code expects a psy struct from the caller, which is only
> available once the device has been registered, so the device gets
> registered with its hardware constraints (e.g. charging current) not yet
> fully filled in.
>
> Fix the former by preventing the unregistration of the psy device before
> its callbacks complete, and the latter by providing a battery parsing
> helper which doesn't require a psy struct from the caller (as it doesn't
> strictly need one).
>
> While here, fix up these and other adjacent issues in bq257xx where all of
> it was discovered.
>
> Signed-off-by: Alexey Charkov <alchark@xxxxxxxxxxx>
> ---
> Alexey Charkov (5):
>       power: supply: core: prevent unregistering a power supply while a callback runs
>       power: supply: core: Allow getting battery info before psy is registered
>       power: supply: bq257xx: Don't ignore errors from bq257xx_get_state()
>       power: supply: bq257xx: Use psy directly instead of driver data
>       power: supply: bq257xx: Parse battery info before registering power supply

Sashiko gave valuable feedback on this series [1], which I'll address
in v2 - except for the part where it thought up a non-USB supply for
bq257xx, which the driver explicitly doesn't support.

[1] https://sashiko.dev/#/patchset/20260907-bq257xx-init-v1-0-1a08b29e1a68%40flipper.net

Best regards,
Alexey