Add detailed documentation regarding the new axp20x_usb_power parameters
Signed-off-by: Ene Alexandru <[email protected]>
---
.../bindings/power_supply/axp20x_usb_power.txt | 32 ++++++++++++++++++++
1 file changed, 32 insertions(+)
diff --git
a/Documentation/devicetree/bindings/power_supply/axp20x_usb_power.txt
b/Documentation/devicetree/bindings/power_supply/axp20x_usb_power.txt
index 862f4a4..ebce8ca 100644
--- a/Documentation/devicetree/bindings/power_supply/axp20x_usb_power.txt
+++ b/Documentation/devicetree/bindings/power_supply/axp20x_usb_power.txt
@@ -5,6 +5,35 @@ Required Properties:
This node is a subnode of the axp20x PMIC.
+The following 3 parameters are configurable from the device-tree:
+ - vhold-enable
+ - this field, if present will enable the VBUS protection feature
+ - the protection feature will disconnect V_USB is the input voltage
is under the vhold-set limit
+ and / or the current is over the ibus-limit
+ - accepted values:
+ - 0 : disabled
+ - 1 : enabled
+
+ - vhold-set
+ - this field configures the V_USB undervoltage limit
+ - if this power path is enabled and V_USB falls bellow the
configured values, the power path will be disabled
+ - available values are from 4000000uV to 4700000uV in 100000uV
increments
+ - the default value is 4400000uV
+ - values out of range are ignored
+
+ - ibus-limit
+ - this field configures the maximum current the board is allowed to
draw from V_USB
+ - available values are:
+ - 100000uA
+ - 500000uA
+ - 900000uA
+ - any other value will disable the ibus-limit check
+
+If any of the above fields it's not present, then it's corresponding hardware
setting is not altered.
+For example, if you want to enable the protection feature but keep the
hardware default values you can leave only "vhold-enable = <0x01>" in the
configuration field.
+If you want to keep the current settings you can ommit all 3 parameters.
+
+
Example:
axp209: pmic@34 {
@@ -30,5 +59,8 @@ axp209: pmic@34 {
usb-power-supply: usb-power-supply {
compatible = "x-powers,axp202-usb-power-supply";
+ vhold-enable = <1>;
+ vhold-set = <4400000>;
+ ibus-limit = <900000>;
};
};
--
1.7.10.4
--
You received this message because you are subscribed to the Google Groups
"linux-sunxi" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
For more options, visit https://groups.google.com/d/optout.
