Re: usb: gadget: f_fs: O_NONBLOCK waits MAX_SCHEDULE_TIMEOUT

From: Baxter, Jim
Date: Wed Apr 01 2015 - 13:29:24 EST


>
> FunctionFS is very specific, because read/write operations are directly
> translated into USB requests, which are asynchronous, so you cannot use
> O_NONBLOCK.
>
> If you need non-blocking API you can use Asynchronous I/O (AIO). You can
> find some examples in kernel sources (tools/usb/ffs-aio-example/).
>
> Br,
> Robert Baldyga
>

Thank you, that sounds like the best approach.
In this case I think perhaps the long wait without any data is an
problem with the imx6 Chipidea USB controller.

I guess it should suspend and drop the connections if there is no
traffic for more than 10ms?

Thanks.
Jim Baxter
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