The X-Powers AXP20X and AXP22X PMICs have an AC entry to supply power to
the board. They have a few registers dedicated to the status of the AC
power supply.

This adds the DT binding documentation for the AC power supply for
AXP20X and AXP22X PMICs.

Signed-off-by: Quentin Schulz <redacted>
---
 .../bindings/power/supply/axp20x_ac_power.txt      | 28 ++++++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/power/supply/axp20x_ac_power.txt

diff --git a/Documentation/devicetree/bindings/power/supply/axp20x_ac_power.txt b/Documentation/devicetree/bindings/power/supply/axp20x_ac_power.txt
new file mode 100644
index 0000000..16d0de4
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/supply/axp20x_ac_power.txt

@@ -0,0 +1,28 @@
+AXP20X and AXP22X PMICs' AC power supply
+
+Required Properties:
+ - compatible: One of:
+			"x-powers,axp202-ac-power-supply"
+			"x-powers,axp221-ac-power-supply"
+
+More Required Properties for AXP20X PMICs:
+ - io-channels: phandles to ACIN voltage and current ADC channels
+ - io-channel-names = "acin_v", "acin_i";
+
+This node is a subnode of the axp20x PMIC.
+
+The AXP20X can read the current current and voltage supplied by AC by
+reading ADC channels from the AXP20X ADC.
+
+The AXP22X is only able to tell if an AC power supply is present and
+usable.
+
+Example:
+
+&axp209 {
+	ac_power_supply: ac_power_supply {