I'm running KDE on Fedora Workstation 21.
When I wake up my machine after suspending it, it always prompts for my password.
If there any way to disable this? I've looked through the settings but can't see how this is done.
Power management -> advanced settings -> Lock screen on resume.
EDIT: In new Plasma vesrions, it's in
System settings -> Desktop Behaviour -> Screen locking.
Quick tip: In the systemsettings screen, there is an useful dialong in which you can search for "lock", it'll highlight the relevant icons.
TDEpowersave does it on this laptop. Locate its icon on the panel, it looks like a power plug with a battery bar beside it. Right-click, select settings, and look for something like "screen lock" (sorry, can't guess the exact English wording, an i18n version here.) Disable it. Did the trick for me.