Re: [PATCH 0/3] Configure usb0 as peripheral on am335x boards

From: Roger Quadros
Date: Mon Jul 03 2023 - 09:44:25 EST




On 03/07/2023 14:56, Julien Panis wrote:
> On 6/30/23 21:40, Roger Quadros wrote:
>> Hi,
>>
>> On 30/06/2023 11:30, Julien Panis wrote:
>>> Hello Tony,
>>>
>>> On 6/30/23 09:20, Tony Lindgren wrote:
>>>> Hi,
>>>>
>>>> * Julien Panis <jpanis@xxxxxxxxxxxx> [230629 13:10]:
>>>>> This series configures usb0 dr_mode as 'peripheral' for am335x-evm,
>>>>> am335x-evmsk, and am335x-icev2. This USB port is mainly used for
>>>>> RNDIS and DFU.
>>>> Is this a mini-B connector? Just wondering if it was originally attempted
>>>> to be configured as OTG or how it ended up with a host configuration..
>>> It's a micro USB-AB connector.
>>> I don't know how it ended up with a host configuration, it looks like an oversight.
>>> Maybe Vignesh or Nishanth can confirm (?)
>> usb0 role should be "otg".
>> It is rightly so in Linux DT. am33xx.dtsi contains "otg" and all AM335x board files inherit from it.
>>
>> So I don't think setting it to "peripheral" in u-boot is the right thing to do.
>
> This series is for kernel (not for u-boot).
> Why is it a problem to set usb0 as 'peripheral' in kernel for the 3 board dts ?
>
> With usb0 not set as 'peripheral', the 3 boards (am335x-evm, evm-sk, icev2)
> do not boot with uboot 2023.04. This error is returned, with LOG_LEVEL=5:
>     No USB device found
>     USB ether init failed
>     initcall sequence 8ffdbba4 failed at call 808024d9 (err=-19)
>     ### ERROR ### Please RESET the board ###
> This error is also returned with usb0 as 'otg'.

This error is at u-boot correct? This will need further investigation.

Does it function correctly in Linux when kept as 'otg'?

--
cheers,
-roger