On Sun, Jan 30, 2022 at 09:45:38PM +0100, Hans de Goede wrote: > Some (USB) charger ICs have variants with USB D+ and D- pins to do their > own builtin charger-type detection, like e.g. the bq24190 and bq25890 and > also variants which lack this functionality, e.g. the bq24192 and bq25892. > > In case the charger-type; and thus the input-current-limit detection is > done outside the charger IC then we need some way to communicate this to > the charger IC. In the past extcon was used for this, but if the external > detection does e.g. full USB PD negotiation then the extcon cable-types do > not convey enough information. > > For these setups it was decided to model the external charging "brick" > and the parameters negotiated with it as a power_supply class-device > itself; and power_supply_set_input_current_limit_from_supplier() was > introduced to allow drivers to get the input-current-limit this way. > > But in some cases psy drivers may want to know other properties, e.g. the > bq25892 can do "quick-charge" negotiation by pulsing its current draw, > but this should only be done if the usb_type psy-property of its supplier > is set to DCP (and device-properties indicate the board allows higher > voltages). > > Instead of adding extra helper functions for each property which > a psy-driver wants to query from its supplier, refactor > power_supply_set_input_current_limit_from_supplier() into a > more generic power_supply_get_property_from_supplier() function. ... > + ret = power_supply_get_property_from_supplier(bdi->charger, > + POWER_SUPPLY_PROP_CURRENT_MAX, > + &val); > + if (ret == 0) Can it be as simple as if (ret) return; ... ? Or did I misunderstand the meaning of 0? -- With Best Regards, Andy Shevchenko
