From mboxrd@z Thu Jan  1 00:00:00 1970
From: maxime.ripard@free-electrons.com (Maxime Ripard)
Date: Mon, 15 Jan 2018 16:33:54 +0100
Subject: [PATCH v2] arm64: allwinner: a64: orangepi-zero-plus2: add usb otg
In-Reply-To: <8080607.cgOBd57Bn1@ice-x220i>
References: <1515748144-25204-1-git-send-email-jagan@amarulasolutions.com>
 <20180115080139.k2vrczo3hnvdt3df@flea.lan>
 <8080607.cgOBd57Bn1@ice-x220i>
Message-ID: <20180115153354.4anukmnd64yj3oec@flea.lan>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Mon, Jan 15, 2018 at 04:05:07PM +0800, Icenowy Zheng wrote:
> ? 2018?1?15???? CST ??4:01:39?Maxime Ripard ???
> > Hi,
> > 
> > On Fri, Jan 12, 2018 at 02:39:04PM +0530, Jagan Teki wrote:
> > > Add usb otg support for orangepi-zero-plus2 board:
> > > - Add usb_otg node with dr_mode as 'otg'
> > > - USB0-IDDET connected to PA21
> > > - VBUS connected through DCIN which always on
> > > 
> > > Tested mass storage function.
> > > 
> > > Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
> > > ---
> > > Changes for v2:
> > > - Change dr_mode to peripheral
> > > 
> > >  .../dts/allwinner/sun50i-h5-orangepi-zero-plus2.dts    | 18
> > >  ++++++++++++++++++ 1 file changed, 18 insertions(+)
> > > 
> > > diff --git
> > > a/arch/arm64/boot/dts/allwinner/sun50i-h5-orangepi-zero-plus2.dts
> > > b/arch/arm64/boot/dts/allwinner/sun50i-h5-orangepi-zero-plus2.dts index
> > > af43533..6511190 100644
> > > --- a/arch/arm64/boot/dts/allwinner/sun50i-h5-orangepi-zero-plus2.dts
> > > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h5-orangepi-zero-plus2.dts
> > > @@ -73,6 +73,10 @@
> > > 
> > >  	};
> > >  
> > >  };
> > > 
> > > +&ehci0 {
> > > +	status = "okay";
> > > +};
> > > +
> > > 
> > >  &mmc0 {
> > >  
> > >  	pinctrl-names = "default";
> > >  	pinctrl-0 = <&mmc0_pins_a>;
> > > 
> > > @@ -111,6 +115,10 @@
> > > 
> > >  	status = "okay";
> > >  
> > >  };
> > > 
> > > +&ohci0 {
> > > +	status = "okay";
> > > +};
> > > +
> > > 
> > >  &uart0 {
> > >  
> > >  	pinctrl-names = "default";
> > >  	pinctrl-0 = <&uart0_pins_a>;
> > > 
> > > @@ -122,3 +130,13 @@
> > > 
> > >  	pinctrl-0 = <&uart1_pins>, <&uart1_rts_cts_pins>;
> > >  	status = "okay";
> > >  
> > >  };
> > > 
> > > +
> > > +&usb_otg {
> > > +	dr_mode = "peripheral";
> > 
> > If VBUS is always on, this can only operate safely in host mode, not
> > peripheral.
> 
> I think this kind of device is designed to directly drain power from the host 
> in peripheral mode.

Then the commit log has it backwards, VBUS is not connected through
DCIN, DCIN is VBUS.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
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