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Subject: Re: [PATCH 2/2] usb: dwc3: pci add property to allow user space role
 switch
To:     Felipe Balbi <balbi@kernel.org>
Cc:     gregkh@linuxfoundation.org, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org, kun.liu2@amd.com,
        alexander.deucher@amd.com
References: <20210823184449.2796184-1-Nehal-Bakulchandra.shah@amd.com>
 <20210823184449.2796184-3-Nehal-Bakulchandra.shah@amd.com>
 <87pmu36ypp.fsf@kernel.org>
From:   "Shah, Nehal-bakulchandra" <nehal-bakulchandra.shah@amd.com>
Message-ID: <1d9ecba4-d180-2193-66a3-3812759e1916@amd.com>
Date:   Tue, 24 Aug 2021 21:32:32 +0530
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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.

Regards
Nehal Shah