I currently seeing this problem with my laptop (Toshiba Satellite A215-S7437), which has the RTL8187B USB dongle chip for the internal wireless. In turn the rtl8187 driver is used for it, and the mac80211 module (and cfg80211). I ran a few tests with the machine and it appears that while the driver module (and associated modules) are loaded, this prevents the machine from properly suspending/hybernate. The only way I have tested this is by stopping the wireless connection and deactivating wireless entirely from within NetworkManager, and then manually unloading the modules (rmmod {rtl8187,mac80211,cfg80211}) in that order. If I then suspend/hybernate the machine it does without any issues, however if I fail to unload the modules (or so I would think) the machine does not suspend. I lack the knowledge to exactly know what is preventing the machine from properly suspending/hybernatin while the driver is loaded, all I know is that when I try to suspend/hybernate the machine with the driver loaded the process starts (shuts down the monitor, but never fully goes into suspension, gets unresponsive and I have to power-cycle the machine).

If there is any further information I could provide, I'd love to do so, I only need to know how to obtain said information.