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Message-ID: <babf5f20-ddf4-74bf-1788-f8e356acaa92@baylibre.com>
Date:   Mon, 3 Jul 2023 13:56:52 +0200
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Subject: Re: [PATCH 0/3] Configure usb0 as peripheral on am335x boards
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To:     Roger Quadros <rogerq@kernel.org>, Tony Lindgren <tony@atomide.com>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>, linux-omap@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        vigneshr@ti.com, nm@ti.com
References: <20230629-usb0-as-peripheral-v1-0-167f78a11746@baylibre.com>
 <20230630072047.GK14287@atomide.com>
 <f4fa80fd-1a6a-4718-0287-f5288cd9d912@baylibre.com>
 <7f44798b-e2bf-1620-da37-ca13bfd07a21@kernel.org>
From:   Julien Panis <jpanis@baylibre.com>
In-Reply-To: <7f44798b-e2bf-1620-da37-ca13bfd07a21@kernel.org>
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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@baylibre.com> [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'.

Julien Panis