Beaglebone USB driver (Mentor Graphics OTG)

Hans Petter Selasky hps at bitfrost.no
Sun Apr 7 07:23:56 UTC 2013


On 04/07/13 09:04, Hans Petter Selasky wrote:
>
> 3) Make sure that channels are not generating tokens if they are aborted
> / cancelled / timedout. This can not be verified using a USB mass
> storage device. Verify this by connecting a USB serial adapter. Try to
> open/close /dev/cuaU0. Make sure it does not loose any bytes and that
> channel cancel does not hang forever.

Hi,

I recommend that cancel works like this:

1) Set invalid device address, like 127.

2) Use DMA delay feature to make a 4ms wait (see XHCI driver for example).

3) Free host channel (final).

--HPS


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