tree: 46e566fca3860151068a949c5de2ffa9706b9987 [path history] [tgz]
  1. tests/
  3. device_watcher.h
  5. fdio_device_watcher.h
  7. input_interpreter.h
  9. input_reader.h
  10. OWNERS

Input Report Reader

This directory contains the Input Report Reader, a library which binds to the InputReport Drivers and parses their reports into fuchsia.ui.input:InputReports.


This program cannot be run directly. It exists in the system as a library used by RootPresenter.

This library should not be used in new programs, as fuchsia.ui.input:InputReports is deprecated.


This program has the following test command:

Interface test:

fx test input-report-reader-test

Class Organization

InputReader is the top-level class that is created and holds all other classes. InputReader is responsible for creating the device watchers for the system. At the moment we only have one type of DeviceWatcher, FdioDeviceWatcher. FdioDeviceWatcher watches for new InputReport devices. These devices appear as files in the /dev/class/input-report/ directory.

When FdioDeviceWatcher discovers a new device, it creates a channel to the device. This channel is then passed through a callback up to InputReader. InputReader creates an InputInterpreter with the new channel.

The InputInterpreter class is the class that drives the sending and receiving of reports from the Driver. InputInterpreter gets a Report Descriptor and parses the data into the form necessary for RootPresenter. If the Report Descriptor contains a Touch device, ConsumerControl device, or Mouse device, then the correct fuchsa.ui.input:InputDevicePtr will be allocated to send reports and descriptors to RootPresenter.

Class Relationships

  • An InputReader has exactly one DeviceWatcher.
  • An InputReader may have one or more InputInterpreter classes.
  • An InputInterpreter has exactly one zx::channel representing a driver.