// Copyright 2020 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
library fuchsia.hardware.vreg;

using zx;

// The output for this voltage regulator is defined by the
// following formula:
//
//  v_out = min_voltage + step_size * step
//
// Where the `step` is programmable by software.

type VregParams = struct {
    // Minimum voltage supported by this voltage regulator.
    min_uv uint32;

    // Voltage increment at each step.
    step_size_uv uint32;

    // Max number of steps.
    num_steps uint32;
};

@transport("Banjo")
@banjo_layout("ddk-protocol")
protocol Vreg {
    // Set the step which yields a voltage of min_uv + step_size_uv * step.
    SetVoltageStep(struct {
        step uint32;
    }) -> (struct {
        st zx.status;
    });

    // Get the current step.
    GetVoltageStep() -> (struct {
        result uint32;
    });

    // Obtain the parameters for this voltage regulator.
    GetRegulatorParams() -> (struct {
        params VregParams;
    });
};