[PATCH v2 06/11] phy: da8xx-usb: new driver for DA8XX SoC USB PHY

Sergei Shtylyov sergei.shtylyov at cogentembedded.com
Fri Apr 1 12:49:25 PDT 2016


On 04/01/2016 07:19 PM, Bin Liu wrote:

>>>>> +EXPORT_SYMBOL_GPL(da8xx_usb20_phy_set_mode);
>>>>
>>>> Don't prefer export symbols from PHY driver. That'll create unnecessary
>>>> dependencies between the controller and the PHY.
>>>
>>> Agreed.
>>>
>>>>
>>>> I think it'll be better to create a new attribute and use it?
>>>
>>> Another simpler option is to not support _set_mode() for DA8xx, and the
>>> phy driver set the otgmode bit in probe() based on dr_mode of the
>>> controller.
>>>
>>> Regards,
>>> -Bin.
>>>
>>
>> This certainly works for my particular use case, however, Sergei
>> Shtylyov, who wrote the da8xx musb glue layer originally, seemed to
>> recall in his review of the patch series that this really is
>> necessary for OTG mode to work properly.
>
> I don't know much about the usb module on DA8xx, but it seems to me that
> _set_mode() has nothing to do with OTG mode.

    No, it does.

> musb_core only calls
> _set_mode() in two places - 1) sysfs: musb_mode_store(), 2) init:
> musb_init_controller(). None of them should be related to OTG mode.

    Both these places do select OTG mode.

> Regards,
> -Bin.

MBR, Sergei




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