v0.2 is an API redesign based on what we learned in v0.1. It makes the API less error prone, enables new optimizations, and prepares the API for a planned WebUSB backend.

New Features

• EndpointRead / EndpointWrite adapters that manage transfers and implement std::io and corresponding async IO traits. These are now the "high-level" API recommended unless you want to manage individual transfers. (#141)
• Functions that were previously blocking are available as blocking or async via MaybeFuture. If you are using them asynchronously, you need to enable the smol or tokio features to defer the blocking syscalls to the corresponding runtime's blocking thread pool. (#100)
• Add DeviceInfo::port_chain with the path of port numbers from the root hub to this device. (#71)
• Add list_buses() and BusInfo for information on USB buses. (#77)
• Include error code in TransferError::Unknown. (#64)
• Add Device::device_descriptor for access to device details from an opened device. (#102)
• Windows: Enable RAW_IO for bulk IN endpoints for improved performance. (#6)
• Linux: Enable zero-copy IO with buffers allocated by Endpoint::allocate. (#11)

Fixes

• Windows: Allow claiming associated interfaces of multi-interface functions.
• Windows: List interfaces of composite devices that are bound to WinUSB at the device level.
• Windows: Include hubs in the device list. (#85)

Breaking Changes

• list_devices DeviceInfo::open, Device::from_fd, Device::set_configuration, Device::reset, Interface::set_alt_setting, Device::claim_interface Device::detach_and_claim_interface, and Endpoint::clear_halt now return impl MaybeFuture. Add use nusb::MaybeFuture and call .wait() for previous blocking functionality. Or, to use them from async code, enable the tokio or smol cargo feature of nusb and use .await.
• Queue has been replaced by Endpoint with changes to the buffer type. (#117)
• Interface methods for single bulk and interrupt transfers and TransferFuture have been removed because they had subtle pitfalls regarding cancellation. Use Endpoint::submit followed by next_complete, or switch to the EndpointRead / EndpointWrite adapters.
• Interface and Device methods control_in_blocking + control_out_blocking have been replaced with control_in / control_out with .wait() from MaybeFuture.
• Interface and Device methods control_in + control_out now accept a timeout. Dropping the returned Future no longer cancels the transfer.
• Bulk and Interrupt IN transfers that are not a multiple of the max packet size return an error. (#135)
• DeviceInfo::bus_number (integer) has been replaced with DeviceInfo::bus_id (string).
• Renamed EndpointType to TransferType.
• Renamed descriptor types (#115)
• Use NonZeroU8 for string descriptor indexes.
• Descriptor constructors return Option instead of panic.
• TransferError::Unknown has an integer field for the error code.
• nusb::Error is now a custom error type instead of a re-export of std::io::Error. It still implements Into<std::io::Error> for ?.
• Linux: Root hubs are no longer included in the device list.

Minimum Rust version is now 1.79.

Contributors

@kevinmehall @pgorgon-hem @kirisauce @tuna-f1sh @CCnut @cstrahan @martinling