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Date:   Tue, 15 Sep 2020 11:45:31 +0200
From:   Eugeniu Rosca <erosca@de.adit-jv.com>
To:     Alan Stern <stern@rowland.harvard.edu>,
        Greg KH <gregkh@linuxfoundation.org>
CC:     <linux-usb@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <andrew_gabbasov@mentor.com>, Baxter Jim <jim_baxter@mentor.com>,
        "Natsume, Wataru (ADITJ/SWG)" <wnatsume@jp.adit-jv.com>,
        "Nishiguchi, Naohiro (ADITJ/SWG)" <nnishiguchi@jp.adit-jv.com>,
        =?utf-8?B?5rWF6YeO5oGt5Y+y?= <yasano@jp.adit-jv.com>,
        kernel test robot <rong.a.chen@intel.com>,
        yasushi asano <yazzep@gmail.com>,
        Martin Mueller <Martin.Mueller5@de.bosch.com>,
        Eugeniu Rosca <roscaeugeniu@gmail.com>,
        Eugeniu Rosca <erosca@de.adit-jv.com>
Subject: Re: [PATCH v3] USB: hub.c: decrease the number of attempts of
 enumeration scheme
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Dear Alan,
Dear Greg,

On Fri, Sep 11, 2020 at 11:12:28AM -0400, Alan Stern wrote:

> The thing is, I'm afraid that without these retry loops, some devices
> will stop working.  If that happens, we will not be able to keep this
> patch in place; we will just have to accept that we fail the PET test.
> 
> Alan Stern

Does this mean that Linux community leaves no choice but to ship a
forked kernel (with no chance of alignment to upstream) for
organizations which design embedded devices where USB plays a key
role, hence requires passing the USB-IF Compliance Program [*]?

Is there hope to give users a knob (build-time or run-time) which would
enable the behavior expected and thoroughly described in compliance
docs, particularly chapter "6.7.22 A-UUT Device No Response for
connection timeout" of "USB On-The-Go and Embedded Host Automated
Compliance Plan" [**]?

[*] https://www.usb.org/compliance
[**] https://www.usb.org/sites/default/files/otgeh_compliance_plan_1_2.pdf

-- 
Best regards,
Eugeniu Rosca