On Wed, Apr 21, 2021 at 07:43:18PM +0200, Lucas Stach wrote:

If your driver code drops the rpm refcount to 0 and starts the
autosuspend timer while a cyclic transfer is still in flight this is
clearly a bug. Autosuspend is not there to paper over driver bugs, but
to amortize cost of actually suspending and resuming the hardware. Your
driver code must still work even if the timeout is 0, i.e. the hardware
is immediately suspended after you drop the rpm refcount to 0.

If you still have transfers queued/in-flight the driver code must keep
a rpm reference.

Right, failing to do that is a clear bug.

Please delete unneeded context from mails when replying.  Doing this
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