Re: [PATCH] power: supply: bd71828: add input current limit property

Matti Vaittinen
2026-04-07T06:33:29Z

On 02/04/2026 00:17, Andreas Kemnade wrote:
> Add input current property to be able to work around issues created by
> automatic input limiting and have some control.
> Disabling the automatic management is another step.
>

Hi Andreas!
Long time no chat :)

First of all, thanks for the work you do with the BD71828/79! I do
admire the effort you're willing to put on it :)

I decided to just take a quick look at the BD71815 and BD72720, which
can be operated using the same driver. I didn't see similar control on
BD71815 data-sheet, so I just decided not to dig it further for now.

What comes to the BD72720, there is something:

The BD72720 has a VBUS_INLIM, which is a configurable current limit for
the bus. This, I believe does NOT directly correspond to the DCIN limit.
It _probably_ has similar impact when the DCIN is supplied, and when it
is powerful enough to run the system. However, I believe the VBUS
current limit is also having an impact when setup is powered from the
battery, or when it is in "battery assist" -mode, (where the battery is
used to "complement" the DCIN, if the DCIN isn't strong enough to power
the system).

I am afraid I don't know your use-case for the control of the DCIN input
limit well enough to decide, if the BD72720 would need something similar
- or if the VBUS_INLIM should be tied to the same knob. If you have the
enthusiasm to write some more words ... I am keen on learning! :)