minor improve for xhci_cmd_stop_ep in xhci_configure_reset_endpoint

[Shichun.Ma at dell.com]

Hi HPS,
XHCI spec mentioned this, 
https://www.intel.com/content/dam/www/public/us/en/documents/technical-specifications/extensible-host-controler-interface-usb-xhci.pdf, P443

The Device Context data structure is used in the xHCI architecture as Output by the xHC to report device configuration and state information to system software. The Device Context data structure is pointed to by an entry in the Device Context Base Address Array (refer to sectio

XHCI shoud update this memory.

your diff is ok in my test.

Thanks & Regards,

Shichun Ma
Software Engineer
Dell | Cloud Client Computing
office +86 10 82862579,  Mobile +86 13241851528
shichun_ma at dell.com



________________________________________
From: Hans Petter Selasky <hps at selasky.org>
Sent: Friday, January 10, 2020 5:02 PM
To: Ma, Horse; freebsd-usb at freebsd.org
Cc: Hu, Shunchao
Subject: Re: minor improve for xhci_cmd_stop_ep in xhci_configure_reset_endpoint

[EXTERNAL EMAIL]

On 2020-01-10 09:57, Hans Petter Selasky wrote:
> Hi,
>
> Can you test the attached patch?
>

HI,

How are we sure that the XHCI doesn't cache the device endpoint state in
its internal memory cache. I.E. that it doesn't update the device
context in host memory at all times?

I think it is better to query the XHCI controller and if we get an error
back that is OK.

--HPS