bindings: arm: msm: Add documentation for subsystem sleep_stats_driver

%YAML 1.2

---

$id: http://devicetree.org/schemas/bindings/arm/msm/subsystem-sleep-stats.yaml#

$schema: http://devicetree.org/meta-schemas/core.yaml#

title: The document describes the device tree binding for subsystem-sleep-stats

maintainers:

  - Tushar Nimkar <tnimkar@codeaurora.org>

description: |+

  Differet Subsystems maintains stats data in SMEM.

  It tells about the individual subsystem information at any given

  time like system sleep counts, system sleep last entered at

  and accumulated duration etc. This drive provide a IOCTL way

  to read those stats from respective SMEMs.

The required properties for subsystem stats driver is:

properties:

 compatible:

   Usage: required

   Value type: <string>

   Definition: Should be "qcom,subsystem-sleep-stats".

example:

  - |

    subsystem-sleep-stats {

		compatible = "qcom,subsystem-sleep-stats";

	};