TI BQ24735 Charge Controller
~~~~~~~~~~

Required properties :
 - compatible : "ti,bq24735"

Optional properties :
 - interrupts : Specify the interrupt to be used to trigger when the AC
   adapter is either plugged in or removed.
 - ti,ac-detect-gpios : This GPIO is optionally used to read the AC adapter
   status. This is a Host GPIO that is configured as an input and connected
   to the ACOK pin on the bq24735. Note: for backwards compatibility reasons,
   the GPIO must be active on AC adapter absence despite ACOK being active
   (high) on AC adapter presence.
 - ti,charge-current : Used to control and set the charging current. This value
   must be between 128mA and 8.128A with a 64mA step resolution. The POR value
   is 0x0000h. This number is in mA (e.g. 8192), see spec for more information
   about the ChargeCurrent (0x14h) register.
 - ti,charge-voltage : Used to control and set the charging voltage. This value
   must be between 1.024V and 19.2V with a 16mV step resolution. The POR value
   is 0x0000h. This number is in mV (e.g. 19200), see spec for more information
   about the ChargeVoltage (0x15h) register.
 - ti,input-current : Used to control and set the charger input current. This
   value must be between 128mA and 8.064A with a 128mA step resolution. The
   POR value is 0x1000h. This number is in mA (e.g. 8064), see the spec for
   more information about the InputCurrent (0x3fh) register.
 - ti,external-control : Indicates that the charger is configured externally
   and that the host should not attempt to enable/disable charging or set the
   charge voltage/current.
 - poll-interval : In case 'interrupts' is not specified, poll AC adapter
   presence with this interval (milliseconds).

Example:

	bq24735@9 {
		compatible = "ti,bq24735";
		reg = <0x9>;
		ti,ac-detect-gpios = <&gpio 72 0x1>;
	}
