IIRC it's telepathy-ofono that wakes the screen up for this still (I know, not the greatest architecture...), and powerd/u-s-c are responsible for actually turning it on and off based on proximity. So, as long as the screen is kept on with proximity enabled by telepathy- ofono, u-s-c and powerd should do the right thing and check proximity before turning the display on.
** Also affects: powerd (Ubuntu) Importance: Undecided Status: New ** Changed in: unity8 (Ubuntu) Status: Triaged => Incomplete -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to powerd in Ubuntu. https://bugs.launchpad.net/bugs/1291455 Title: Screen and input should be disabled with proximity sensor when on greeter Status in the base for Ubuntu mobile products: Confirmed Status in powerd package in Ubuntu: New Status in telepathy-ofono package in Ubuntu: Triaged Status in unity8 package in Ubuntu: Incomplete Bug description: Steps to reproduce: * suspend your device * cover the proximity sensor (top left on mako) * call the phone Expecte result: * screen does not light up until you uncover the proximity sensor Current result: * screen lights up and you can answer the call This results in butt/pocket calls... ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: unity8 7.84+14.04.20140306-0ubuntu1 Uname: Linux 3.4.0-5-mako armv7l ApportVersion: 2.13.3-0ubuntu1 Architecture: armhf Date: Wed Mar 12 13:14:37 2014 InstallationDate: Installed on 2014-03-12 (0 days ago) InstallationMedia: Ubuntu Trusty Tahr (development branch) - armhf (20140312) SourcePackage: unity8 UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/canonical-devices-system-image/+bug/1291455/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp