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Device Tree Created Regulator Enable - Write Error

Question asked by Paul DeMetrotion on Jan 27, 2016
Latest reply on Feb 11, 2016 by alejandrolozano

I have the following regulator provided in the device tree:

 

reg_v5_sw: regulator@4 {

            compatible = "regulator-fixed";

            reg = <4>;

            regulator-name = "reg_v5_sw";

            regulator-min-microvolt = <5000000>;

            regulator-max-microvolt = <5000000>;

            gpio = <&gpio4 31 GPIO_ACTIVE_HIGH>;

            enable-active-high;

        };

 

When I boot I have the following available in /sys/class/regulator/regulator.11:

 

drwxr-xr-x 3 root root    0 Jan 26 23:17 .

drwxr-xr-x 3 root root    0 Jan 26 23:17 ..

lrwxrwxrwx 1 root root    0 Jan 26 23:57 device -> ../../../4.regulator

-rw-rw-rw- 1 root root 4096 Jan 26 23:57 microvolts

-rw-rw-rw- 1 root root 4096 Jan 26 23:57 name

-rw-rw-rw- 1 root root 4096 Jan 26 23:57 num_users

drwxr-xr-x 2 root root    0 Jan 26 23:38 power

-rwxrwxrwx 1 root root 4096 Jan 27 01:05 state

lrwxrwxrwx 1 root root    0 Jan 26 23:17 subsystem -> ../../../../../../class/regulator

-rw-rw-rw- 1 root root 4096 Jan 26 23:57 suspend_disk_state

-rw-rw-rw- 1 root root 4096 Jan 26 23:57 suspend_mem_state

-rw-rw-rw- 1 root root 4096 Jan 26 23:57 suspend_standby_state

-rw-rw-rw- 1 root root 4096 Jan 26 23:57 type

-rw-rw-rw- 1 root root 4096 Jan 26 23:57 uevent

 

The name file sows the proper regulator:

 

cat name

reg_v5_sw

 

I am attempting to enable the regulator through the following command but get the error shown.

 

echo "enabled" > state

-sh: echo: write error: Input/output error

 

Any idea why I cannot enable the regulator? Is there another driver grabbing the resource?

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