Re: [PATCH v10 6/6] usb: typec: tcpm/tcpci_maxim: deprecate WAR for setting charger mode

[Heikki Krogerus]

Hi Amit,

On Thu, Apr 02, 2026 at 11:47:30AM -0700, Amit Sunil Dhamne wrote:
> Hi Heikki,
> 
> On 4/2/26 7:33 AM, Heikki Krogerus wrote:
> > Hi Amit,
> > 
> > > +static int get_vbus_regulator_handle(struct max_tcpci_chip *chip)
> > > +{
> > > +	if (IS_ERR_OR_NULL(chip->vbus_reg)) {
> > > +		chip->vbus_reg = devm_regulator_get_exclusive(chip->dev,
> > > +							      "vbus");
> > Sorry to go back to this, but why can't you just get the regulator in
> > max_tcpci_probe()?
> 
> Thanks for calling this out. This was an intentional design decision to
> break a circular dependency.
> 
> The charger driver is guaranteed to probe after the TCPC driver due to a
> power supply dependency (the TCPC is a supplier of power for the Battery
> Charger). However, the charger driver is also the regulator provider for
> VBUS out (when Type-C goes into source mode).
> 
> Because of this, the regulator handle will not be available during the TCPC
> driver's probe. If we tried to fetch it in max_tcpci_probe() and returned
> -EPROBE_DEFER, it would create a probe deadlock, as the charger would then
> never probe. Therefore, I made the decision to get the regulator handle
> lazily and on-demand.

Got it. Thanks for the explanation!

-- 
heikki