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Subject: Re: [PATCH v10 2/7] usb: mux: add generic code for dual role port mux
To: Jun Li <jun.li@nxp.com>, Roger Quadros <rogerq@ti.com>,
        Peter Chen <hzpeterchen@gmail.com>
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From: Lu Baolu <baolu.lu@linux.intel.com>
Message-ID: <5756938E.2010901@linux.intel.com>
Date: Tue, 7 Jun 2016 17:27:42 +0800
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Hi,

On 06/07/2016 02:34 PM, Jun Li wrote:
>> > On 06/07/2016 11:03 AM, Jun Li wrote:
>>> > > Hi Roger
>>> > >
>>>> > >>
>>>> > >> For Mux devices implementing dual-role, the mux device driver _must_
>>>> > >> use OTG/dual-role core API so that a common ABI is presented to user
>>>> > >> space for OTG/dual-role.
>>> > > That's the only point we have concern, do dual role switch through
>>> > > OTG/dual-role core, not do it by itself.
>> > 
>> > That really depends on how do you define "dual role". Can you please
>> > provide an unambiguous definition of "dual role" used in OTG/dual-role
>> > framework?
> Host and peripheral.
>

This is definitely ambiguous.

By reading OTG/dual-role code, my understanding is that "dual-role" is a
"reduced OTG" which is for DRD devices lacking of some OTG negotiation
protocols.

We really can't say "it's the scope of OTG/dual-role" whenever it comes to
"host and peripheral".

Best regards,
Lu Baolu