[PATCH 2/2] ARM: dts: omap5: Add dr_mode for dwc3

Roger Quadros rogerq at ti.com
Mon Sep 8 04:39:08 PDT 2014


On 09/08/2014 02:34 PM, Dmitry Lifshitz wrote:
> Hi Felipe, Roger
> 
> On 04/16/2014 07:16 PM, Felipe Balbi wrote:
>> On Fri, Oct 11, 2013 at 05:46:12PM +0300, Roger Quadros wrote:
>>> Hi,
>>>
>>> On 10/10/2013 01:49 PM, Kishon Vijay Abraham I wrote:
>>>> From: George Cherian <george.cherian at ti.com>
>>>>
>>>> Added dr_mode property in dwc3 and set its default mode to device.
>>>
>>> If there is a specific reason why this is not set to "otg", we need
>>> to explain it here.
>>>
>>> AFAIK the port is meant to be used as OTG port.
>>
>> we still don't have the workaround for dual role ports, I've been
>> working on it but still need to retest and make sure it's working fine
>> before merging upstream.
>>
> 
> 
> Does the OTG port suppose to work with OMAP5? I mean role switching mechanism?
> 
> I'm testing kernel v3.16 with OMAP5 based board (CM-T54).
> 
> If I set CONFIG_USB_DWC3_DUAL_ROLE, than nothing is going on when I plug some device/host cable into micro USB3.0 port (VBUS/ID detection with extcon events works fine).
> 
> CONFIG_USB_DWC3_HOST/CONFIG_USB_DWC3_GADGET bring port to appropriate mode and it works.
> 
> What is the purpose of setting dr_mode = "peripheral" in omap5.dtsi, since it is overridden by config options in dwc3_probe()?

If dual role works it should be "otg" then. I'm not sure why it was set to peripheral. Maybe the role switching mechanism
was not in place earlier.

George any objections for "otg"?

cheers,
-roger



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