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Message-ID: <5C8D0C2B.2010605@baylibre.com>
Date:   Sat, 16 Mar 2019 15:46:03 +0100
From:   Neil Armstrong <narmstrong@baylibre.com>
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To:     Martin Blumenstingl <martin.blumenstingl@googlemail.com>
CC:     khilman@baylibre.com, linux-amlogic@lists.infradead.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 11/11] arm64: dts: meson-g12a-x96-max: Enable USB
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Le 15/03/2019 22:50, Martin Blumenstingl a écrit :
> Hi Neil,
> 
> On Mon, Mar 11, 2019 at 10:58 AM Neil Armstrong <narmstrong@baylibre.com> wrote:
> [...]
>> +&dwc2 {
>> +       status = "okay";
>> +};
> your patch description states that this enables the "USB host ports"
> but dwc2 is only used for peripheral mode (meaning: dr_mode =
> "peripheral" or dr_mode = "otg").
> do we still need to enable dwc2 in a host-only configuration?

DWC2 is peripheral-only, but we can still manually switch one of the
ports and use it as peripheral with a Type-A to Type-A cable, thus
enabling dwc2.

If the OTG capable PHYs was behind an USB Hub or directly connected to
a device, we could disable dwc2, but for now this port is always tied
to a physical Type-A or micro-USB connector.

Maybe it would be sane to always enable dwc2, and disable it for specific
boards only.

Neil

> 
> 
> Regards
> Martin
>