• Implemented a platform driver/platform device infrastructure for HC-SR04 sensors and enabled the Linux sysfs interface for these platform devices to provide the user with a convenient interface to operate the devices, allows the user to: - Set the measurement mode (periodic or one-shot) - Set the frequency of distance measurement sampling for periodic mode - Enable or disable measurement operations on either one or both sensors - Set the trigger and echo GPIO pins - Read the most recently obtained distance value - Tested the driver using the user-dev application program and a script file.