Detecting user inactivity in a multiprocessor communication device

A communication device comprising:

• a user interface (UI);
• a first electronic processor configured to detect and process UI input events;
• and
• a second electronic processor communicatively connected to the first electronic processor and configured to detect and process UI input events,
• wherein the first electronic processor is further configured to
• execute, in a first mode of operation, an application having a user inactivity timeout feature,
• in the first mode, periodically determine a user inactivity time of the communication device, the user inactivity time being an amount of time that no UI input events are detected by the first electronic processor or the second electronic processor,
• in response to determining that the user inactivity time exceeds a first time period, perform a user inactivity timeout function and execute the application in a second mode of operation,
• wherein, in the second mode, the second electronic processor asynchronously reports, to the first electronic processor, UI input events detected by the second electronic processor.

A method for a multiprocessor communication device having a user interface (UI), a first electronic processor that detects UI input events, and a second electronic processor that detects UI input events, the method comprising:

• executing, with a first electronic processor, a first application;
• initializing a countdown timer for a first time period;
• in response to expiration of the countdown timer, determining a user inactivity time for the multiprocessor communication device, the user inactivity time being a lesser of a time since a UI input event was last detected by the first electronic processor and a time since a UI input event was last detected by the second electronic processor, and
• in response to the user inactivity time being greater than or equal to the first time period, performing a first application timeout function that includes at least one selected from the group consisting of disabling a user interface feature of the first application, providing an alert to the user interface that a user inactivity timeout has occurred, transmitting an alert to an external device that a user inactivity timeout has occurred, and entering a power saving state.