> -----Original Message-----
> From: Tim Harvey <tharvey@xxxxxxxxxxxxx>
> Sent: Tuesday, October 18, 2022 3:31 AM
> To: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
> Cc: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>; Shawn Guo
> <shawnguo@xxxxxxxxxx>; Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>;
> devicetree@xxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>; Pengutronix
> Kernel Team <kernel@xxxxxxxxxxxxxx>; Fabio Estevam <festevam@xxxxxxxxx>;
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; Jun Li <jun.li@xxxxxxx>
> Subject: Re: [PATCH v3 1/1] arm64: dts: tqma8mpql: add USB DR support
>
> On Fri, Oct 14, 2022 at 7:18 AM Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> wrote:
> >
> > Hello Alexander,
> >
> > On 05.09.22 09:37, Alexander Stein wrote:
> > > + pinctrl_usb0: usb0grp {
> > > + fsl,pins = <MX8MP_IOMUXC_GPIO1_IO13__USB1_OTG_OC
> 0x1c0>,
> > > + <MX8MP_IOMUXC_GPIO1_IO12__USB1_OTG_PWR
> 0x1c0>;
> > > + };
> > > +
> > > + pinctrl_usbcon0: usb0congrp {
> > > + fsl,pins = <MX8MP_IOMUXC_GPIO1_IO10__GPIO1_IO10
> 0x1c0>;
> > > + };
> >
> > I am wondering: You can mux for MX8MP_IOMUXC_GPIO1_IO10__USB1_OTG_ID,
> > why did you decide against using the hardware function here?
> >
>
> Ahmad,
>
> The IMX8MP USB OTG_ID pins are internally not connected. I can't recall where
> this is mentioned but due to this they can not be used to select host/device
> mode.
There is no *OTG* block in iMX8MP HW due to dwc3 IP upgrade, the OTG ID pin
cannot generate a normal USB irq for host/device selection, instead, we can
use GPIO function to generate ID state change event for it, this is well
supported via usb-conn-gpio.c like this patch is using.
Li Jun
>
> Best Regards,
>
> Tim
