Fri Oct 22 17:57:35 EDT 2010
be marked as an irq, at the bank level. But its corresponding pad will
have its wakeup bit disabled. Would that work? I think yes, in most cases.
Now let's take the WFI instruction as a divisor for 2 situations:
A - common / working case: an interrupt on that gpio still happens after the WFI instruction.
Since the system is in sleep mode and the pad for that gpio is not wakeup
capable, then nothing would happen and the system won't wakeup. Then, I think
everyone is happy here.
B - corner case: an interrupt on that gpio happens before the WFI instruction.
Since the system is active, the gpio bank can still report this interrupt
and will do it. The suspend won't happen due to a irq which has been
explicitly marked as disabled and wakeup incapable.
Then, would that be the expected behavior? Assuming that the driver
has explicitly said to the system, you should not bother about this at all.
More information about the linux-arm-kernel