[U-Boot] [PATCH] usb: dwc3: Handle case where setup_phy is not needed

[Michal Simek]

On 01. 04. 19 12:38, Siva Durga Prasad Paladugu wrote:
> Hi Lukasz,
> 
>> -----Original Message-----
>> From: Lukasz Majewski [mailto:lukma at denx.de]
>> Sent: Monday, April 01, 2019 4:04 PM
>> To: Siva Durga Prasad Paladugu <sivadur at xilinx.com>
>> Cc: u-boot at lists.denx.de; marex at denx.de; jjhiblot at ti.com;
>> sjg at chromium.org; patrick.delaunay at st.com; Michal Simek
>> <michals at xilinx.com>
>> Subject: Re: [PATCH] usb: dwc3: Handle case where setup_phy is not
>> needed
>>
>> On Mon, 1 Apr 2019 10:23:42 +0000
>> Siva Durga Prasad Paladugu <sivadur at xilinx.com> wrote:
>>
>>> Hi Lukasz,
>>>
>>>> -----Original Message-----
>>>> From: Lukasz Majewski [mailto:lukma at denx.de]
>>>> Sent: Monday, April 01, 2019 1:03 PM
>>>> To: Siva Durga Prasad Paladugu <sivadur at xilinx.com>
>>>> Cc: u-boot at lists.denx.de; marex at denx.de; jjhiblot at ti.com;
>>>> sjg at chromium.org; patrick.delaunay at st.com; Michal Simek
>>>> <michals at xilinx.com>
>>>> Subject: Re: [PATCH] usb: dwc3: Handle case where setup_phy is not
>>>> needed
>>>>
>>>> Hi Siva Durga Prasad Paladugu,
>>>>
>>>>> If CONFIG_PHY is not enabled then the dwc3_setup_phy() returns
>>>>> ENOTSUPP which can be still valid and intentional
>>>>                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ - could
>>>> you elaborate on this a bit more?
>>>>
>>>> What is the use case when -ENOTSUPP is valid and intentional ?
>>>
>>> In the cases where phy will be setup by First stage boot loader itself
>>> and don't want to do it again at u-boot.
>>
>> I think that I saw some time ago similar patch for uart - on IMX IIRC (it was
>> also setup by BootROM on SoC).
>>
>> Maybe we would need some kind of switch in Kconfig to indicate this use
>> case?
>>
>> Another option would be to mark this in DTS as TI specific property?
>>
>> My point is that we shall not proceed with the flow when we do receive -
>> ENOTSUPP
> 
> TBH, I feel we should not call dwc3_setup_phy() if CONFIG_PHY is not enabled. If we look at dwc3_setup_phy() definition, it is under 
CONFIG_PHY.

+1 on this.

M