zircon/system/fidl/fuchsia-hardware-usb-peripheral/usb-peripheral.fidl

// Copyright 2018 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.usb.peripheral;

using zx;

struct FunctionDescriptor {
    uint8 interface_class;
    uint8 interface_subclass;
    uint8 interface_protocol;
};

// The fields in DeviceDescriptor match those in usb_descriptor_t in the USB specification.
struct DeviceDescriptor {
    uint16 bcdUSB;
    uint8 bDeviceClass;
    uint8 bDeviceSubClass;
    uint8 bDeviceProtocol;
    uint8 bMaxPacketSize0;
    uint16 idVendor;
    uint16 idProduct;
    uint16 bcdDevice;
    uint8 iManufacturer;
    uint8 iProduct;
    uint8 iSerialNumber;
    uint8 bNumConfigurations;
};

const uint32 MAX_STRING_LENGTH = 127;

// Events protocol that is used as a callback to inform the client
// of the completion of various server-side events.
// This callback interface can be registered using the SetStateChangeListener
// method on the Device protocol.
[Layout = "Simple"]
protocol Events {
    // Invoked when a function registers
    FunctionRegistered() -> ();
};

[Layout = "Simple"]
protocol Device {
    // Sets the device's USB device descriptor.
    SetDeviceDescriptor(DeviceDescriptor desc) -> (zx.status s);
    // Sets a string descriptor a string in the USB device descriptor.
    AllocStringDesc(string:MAX_STRING_LENGTH name) -> (zx.status s, uint8 index);
    // Adds a new function to the USB current configuration.
    // Must be called before BindFunctions or after ClearFunctions.
    AddFunction(FunctionDescriptor desc) -> (zx.status s);
    // Tells the device to create child devices for the configuration's interfaces.
    BindFunctions() -> (zx.status s);
    // Tells the device to remove the child devices for the configuration's interfaces
    // and reset the list of functions to empty.
    ClearFunctions() -> (zx.status s);
    // Returns the current USB mode.
    GetMode() -> (zx.status s, uint32 mode);
    // Sets the current USB mode.
    SetMode(uint32 mode) -> (zx.status s);
    // Adds a state change listener that is invoked when a state change completes.
    SetStateChangeListener(request<Events> listener);
};