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References: <20210823184449.2796184-1-Nehal-Bakulchandra.shah@amd.com>
 <20210823184449.2796184-3-Nehal-Bakulchandra.shah@amd.com>
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From:   Felipe Balbi <balbi@kernel.org>
To:     "Shah, Nehal-bakulchandra" <nehal-bakulchandra.shah@amd.com>
Cc:     gregkh@linuxfoundation.org, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org, kun.liu2@amd.com,
        alexander.deucher@amd.com
Subject: Re: [PATCH 2/2] usb: dwc3: pci add property to allow user space
 role switch
Date:   Tue, 24 Aug 2021 19:17:46 +0300
In-reply-to: <1d9ecba4-d180-2193-66a3-3812759e1916@amd.com>
Message-ID: <87czq27r5w.fsf@kernel.org>
MIME-Version: 1.0
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"Shah, Nehal-bakulchandra" <nehal-bakulchandra.shah@amd.com> writes:

> Hi
> On 8/24/2021 1:49 PM, Felipe Balbi wrote:
>> Nehal Bakulchandra Shah <Nehal-Bakulchandra.shah@amd.com> writes:
>> 
>>> For AMD platform there is a requirement to enable user space role
>>> switch from host to device and device to host by means of running
>>> following commands.
>>>
>>> HOST:   echo host > /sys/class/usb_role/dwc3.0.auto-role-switch/role
>>> DEVICE: echo device > /sys/class/usb_role/dwc3.0.auto-role-switch/role
>> A more important question that needs to be answered: why?
>> 
> Our customer platform is not completely capable of OTG i.e with type C
> controller it does not have PD to support role switching. Hence, they 
> have script which triggers the role switch based on ACPI/EC interrupt.

sounds like some generalized version of this text should be added to
commit log.

-- 
balbi