Re: [PATCH 1/2] dt-bindings: soc: qcom: pmic-glink: Document batteryless property

[Kamal Wadhwa]

On Tue, May 19, 2026 at 12:35:13PM +0200, Krzysztof Kozlowski wrote:
> On Tue, May 19, 2026 at 01:55:26PM +0530, Rakesh Kota wrote:
> > 
> > > And isn't lack of monitored battery property enough to indicate that?
> > 
> > Regarding monitored-battery — its absence alone isn't sufficient. The
> > BATT_ID line on debug boards is pulled to ~10kΩ, which is used during
> > development phase where some battery properties are still present. The
> > same ~10kΩ value is also used on some genuinely battery-less production
> > platforms where no battery properties exist, making auto-detection
> > unreliable. Hence the need for an explicit DT property to identify
> > hardware platforms where no battery populated. 
> 
> I don't understand this logic. So you claim you have debug boards which
> do not have battery, but define monitored-battery? Then these are wrong
> and fix them first.

Actually our firmware treats the debug board as a "fake battery" rather then
a "no-battery" case.

This is done to avoid triggering shutdown or trigger power/thermal related
mitigations to kick in from the HLOS (android) that is configured mainly for
battery-backed devices.

Note that we can know if its a debug board, just by looking at the battery
ID resistance or the battery profile name in the power supply properties
for `qcom-battmgr-bat` in sysfs.

However, the problem started with the boards that are battery-less and
unfortunetely used the same debug board batt ID resistance value, so from
the firmware side the batteryless board is also seen same as a board with
debug-board connected.

Since firmware does not have a way to dynamically tell if it on a
debug-board powered device or a DCIN powered device, We are required to
add this new DT property.

Regards,
Kamal


> 
> Best regards,
> Krzysztof
>