u-boot/doc/device-tree-bindings/regulator/fixed.txt
Peng Fan 39dd00fc5d drivers: regulator: fixed: add u-boot, off-on-delay-us
Add u-boot,off-on-delay-us for fixed regulator.

Depends on board design, the gpio regulator sometimes
connects with a big capacitance. When need to off, then
on the regulator, if there is no enough delay,
the voltage does not drop to 0, so introduce this
property to handle such case.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-19 20:38:39 -04:00

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Text

Fixed Voltage regulator
Binding:
The binding is done by the property "compatible" - this is different, than for
binding by the node prefix (doc/device-tree-bindings/regulator/regulator.txt).
Required properties:
- compatible: "regulator-fixed"
- regulator-name: this is required by the regulator uclass
Optional properties:
- gpio: GPIO to use for enable control
- startup-delay-us: startup time in microseconds
- u-boot,off-on-delay-us: off delay time in microseconds
- regulator constraints (binding info: regulator.txt)
- enable-active-high: Polarity of GPIO is Active high. If this property
is missing, the default assumed is Active low.
Other kernel-style properties, are currently not used.
Note:
For the regulator constraints, driver expects that:
- regulator-min-microvolt is equal to regulator-max-microvolt
- regulator-min-microamp is equal to regulator-max-microamp
Example:
fixed_regulator@0 {
/* Mandatory */
compatible = "regulator-fixed";
regulator-name = "LED_3.3V";
/* Optional: */
gpio = <&gpc1 0 GPIO_ACTIVE_LOW>;
/* Optional for regulator uclass */
regulator-min-microvolt = <3300000>;
regulator-max-microvolt = <3300000>;
regulator-min-microamp = <15000>;
regulator-max-microamp = <15000>;
regulator-always-on;
regulator-boot-on;
enable-active-high;
};