Suspend and Freeze Paths

“Issues reported during the suspend-to-disk process lead Linux
creator Linus Torvalds to suggest, ‘please–just make the f*cking
suspend-to-disk use other routines already. 99% of all hardware
needs to do exactly *nothing* on suspend-to-disk, and the ones that
really do need things tend to need to not do a whole lot.’ He went
on to explain why sharing the code path for suspend-to-disk and
freezing to RAM is wrong:

“‘For example, the ‘freeze’ action for USB (which is one of the
hardest things to suspend) should literally be something like just
setting the controller STOP bit, and waiting for it to have
stopped…'”

Complete
Story