| // 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.i2c; |
| |
| using zx; |
| |
| const uint32 MAX_TRANSFER_SIZE = 8196; // More than enough for I2C |
| |
| enum SegmentType { |
| /// Flags the end of a serialized list of segments. |
| END = 1; |
| /// Segment to be read from the I2C device. |
| READ = 2; |
| /// Segment to be written to the I2C device. |
| WRITE = 3; |
| }; |
| |
| /// Segment header for a serialized SubordinateTransfer. |
| /// TODO(ZX-3029): Avoid requiring serialization and have SubordinateTransfer take an argument of |
| /// `vector<Segment>:MAX_SEGMENTS` instead once we have better support in the C bindings or for C++. |
| struct Segment { |
| uint32 type; |
| uint32 len; |
| }; |
| |
| [Layout = "Simple"] |
| protocol Device { |
| /// Send and receive data on the I2C device. |
| SubordinateTransfer(vector<uint8>:MAX_TRANSFER_SIZE in) -> (zx.status s, |
| vector<uint8>:MAX_TRANSFER_SIZE out); |
| }; |