Re: Should the USB device to go into suspend when the USB host is suspended?

Sivaraj wrote:
Arlet wrote:
Sivaraj wrote:
Sivaraj wrote:

Is it necessary/MUST for the USB device to go into suspend when
the USB host is suspended, provided that the device is Remote-
Wakeup Enabled? What the spec says?

Can anybody please share your views on this?

Don't top-post. Have some patience (24 hours is a good time to
wait). Make sure you provide necessary details for the answer.
For example, what "host" and what "spec" are you talking about ?

Host -> PC
Spec -> USB spec

I am sorry for the top-post, i am new to this. Also i needed the
answer in quick time, i will correct myself when i post in future.
Thanks for all your responses. Then the spec doesn't hav the info
i am looking. Actually I am testing a scenario where I am
suspending the host PC and observing the behavior of the attached
USB device. I want to know this:

When I suspend the host the USB bus will be suspeneded, So if any
connected USB device will not get the bus power during this period,
in this case, what should be state of the device, should the state
be suspended or normal?

"what host" includes at least the OS in use. For example, Linux
(and which one), FreeBSD, OS2, Winslush, etc. After that what
hardware, i.e. CPU, chipset, manufacturer (i.e. what bios), etc.

For USB specifications I suggest google. The specification is
public, but I can't give you a URL. Most systems can (not
necessarily do) supply USB power from the auxiliary supply, even
when turned off. This is often configurable.

--
Chuck F (cbfalconer at maineline dot net)
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home.att.net>


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