Fixed MTP to work with TWRP

Documentation/devicetree/bindings/gpio/gpio-poweroff.txt

@@ -0,0 +1,36 @@
+Driver a GPIO line that can be used to turn the power off.
+
+The driver supports both level triggered and edge triggered power off.
+At driver load time, the driver will request the given gpio line and
+install a pm_power_off handler. If the optional properties 'input' is
+not found, the GPIO line will be driven in the inactive
+state. Otherwise its configured as an input.
+
+When the pm_power_off is called, the gpio is configured as an output,
+and drive active, so triggering a level triggered power off
+condition. This will also cause an inactive->active edge condition, so
+triggering positive edge triggered power off. After a delay of 100ms,
+the GPIO is set to inactive, thus causing an active->inactive edge,
+triggering negative edge triggered power off. After another 100ms
+delay the GPIO is driver active again. If the power is still on and
+the CPU still running after a 3000ms delay, a WARN_ON(1) is emitted.
+
+Required properties:
+- compatible : should be "gpio-poweroff".
+- gpios : The GPIO to set high/low, see "gpios property" in
+  Documentation/devicetree/bindings/gpio/gpio.txt. If the pin should be
+  low to power down the board set it to "Active Low", otherwise set
+  gpio to "Active High".
+
+Optional properties:
+- input : Initially configure the GPIO line as an input. Only reconfigure
+  it to an output when the pm_power_off function is called. If this optional
+  property is not specified, the GPIO is initialized as an output in its
+  inactive state.
+
+Examples:
+
+gpio-poweroff {
+	compatible = "gpio-poweroff";
+	gpios = <&gpio 4 0>;
+};