DT support for input-supply of regulator.

[Laxman Dewangan <ldewangan@nvidia.com>]

Hi Mark,
When mapping the dts file for different regulator, observe that the 
input  input-supply is not getting correctly.


I have following structure in the dts file for registering the regulators:

        pmu: tps65910@d2 {
                 compatible = "ti,tps65910";
                 reg = <0xd2>;

                 #gpio-cells = <2>;
                 gpio-controller;
::::::::::

                 regulators {
                         vdd1_reg: vdd1 {
                                 regulator-min-microvolt = < 600000>;
                                 regulator-max-microvolt = <1500000>;
                         };
                         vdd2_reg: vdd2 {
                                 regulator-min-microvolt = < 600000>;
                                 regulator-max-microvolt = <1500000>;
                                 vin-supply = <&vdd1_reg>
                         };
                 };
     };


Now the regulator vdd1 get register properly, but when looking for the 
registration for vdd2, it is not able to identify the 
init_data->supply_regulator as we do not parse it.
So for this, I added the code in case on such
In function of_get_regulation_constraints()
         if (of_find_property(np, "vin-supply", NULL))
                 (*init_data)->supply_regulator = "vin";

So when vdd2 registration happen, it looks for the vin-supply.

But when it looks for the device node containing this regulator, it 
starts searching of the props from the dev_node of parent device i.e. 
pmu: tps65910@d2 and in search, it does not found the vin-supply 
property. It got property for compatible reg, gpio_cell, gpio-controller 
and then no more property.

Is there any issue in laying down the regulator structure?

Thanks,
Laxman