power: supply: Add power_supply_set_input_current_limit_from_supplier helper

On some devices the USB Type-C port power (USB PD 2.0) negotiation is
done by a separate port-controller IC, while the current limit is
controlled through another (charger) IC.

It has been decided to model this by modelling the external Type-C
power brick (adapter/charger) as a power-supply class device which
supplies the charger-IC, with its voltage-now and current-max representing
the negotiated voltage and max current draw.

This commit adds a power_supply_set_input_current_limit_from_supplier
helper function which charger power-supply drivers can call to get
the max-current from their supplier and have this applied
through their set_property call-back to their input-current-limit.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index de89066b72b1..79e90b3d3288 100644
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -332,6 +332,8 @@ extern int power_supply_get_battery_info(struct power_supply *psy,
                                          struct power_supply_battery_info *info);
 extern void power_supply_changed(struct power_supply *psy);
 extern int power_supply_am_i_supplied(struct power_supply *psy);
+extern int power_supply_set_input_current_limit_from_supplier(
+                                         struct power_supply *psy);
 extern int power_supply_set_battery_charged(struct power_supply *psy);
 
 #ifdef CONFIG_POWER_SUPPLY