zircon/system/banjo/ddk.protocol.i2cimpl/i2c-impl.banjo

// 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 ddk.protocol.i2cimpl;

using zx;

/// See `Transact` below for usage.
struct I2cImplOp {
    uint16 address;
    vector<voidptr>? data;
    bool is_read;
    bool stop;
};

/// Low-level protocol for i2c drivers.
[Layout = "ddk-protocol"]
protocol I2cImpl {
    GetBusCount() -> (uint32 count);
    GetMaxTransferSize(uint32 bus_id) -> (zx.status s, usize size);
    /// Sets the bitrate for the i2c bus in KHz units.
    SetBitrate(uint32 bus_id, uint32 bitrate) -> (zx.status s);
    /// |Transact| assumes that all ops buf are not null.
    /// |Transact| assumes that all ops length are not zero.
    /// |Transact| assumes that at least the last op has stop set to true.
    Transact(uint32 bus_id, vector<I2cImplOp> op) -> (zx.status status);
};