Alcor Micro AU9540 - AU9540 USB Selective Suspend Feature

AU9540 USB Smart Card Reader V1.6
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AU9540 into the host.
5. When AU9540 is not
inserted into the host
and the host is in
suspend mode. Plug
A
U9540 into the host
with smart card inserted
in advance.
Host will be woken up and
detect AU9540. After the host
is woken up, AU9540 is ready
to operate card now.
6. When AU9540 is
inserted into the host,
insert a smart card into
A
U9540. Then get host
into suspend mode.
A
fter that, remove the
smart card from
A
U9540. Then plug in
the smart card again.
When user removes the card, it
will not wake up the host from
suspend mode. Then insert a
card. It will wake up the host.
A
fter the host is woken up,
A
U9540 will be ready to
operate the card.
7. When there is no card
inserted into AU9540
and the host is in
suspend mode, plug
A
U9540 into the host.
Then, insert a smart
card into AU9540.
When AU9540 is plugged into
the host without card inserted,
the host will not be woken up.
However, if user inserts a card
now, the host will be woken up.
This feature must work with
host system that supports
remote-wake up.
6. USB Selective Suspend Feature
The driver determines whether it should enter selective suspend state by the following
requirements.
1. The card is in power off state or there is no card in the reader.
2. The reader is idle at least for a given time (30 seconds by default). It means during
the period there is no command issuing to reader and there is no card
inserting/removing event occurs.
When the driver detects both the two requirements above are met, it starts processing
the following tasks,
1. Send standard USB command to the reader to enable remote wake function.
2. Start selective-suspend procedure to ask the system to suspend the reader.
After entering the selective suspend state, the driver determines whether it should exit
selective suspend state when one of the following conditions occurs,
1. There is any command which intend to communicate with the reader.
2. When card inserting/removing event occurs, the reader issues resume signal to the
host. Then the system will inform the driver to exit selective suspend state.