Re: [PATCH] ARM: multi_v7_defconfig: Select CONFIG_USB_ONBOARD_DEV as built-in

From: Matthias Kaehlcke <mka@chromium.org>
To: Fabio Estevam <festevam@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>,
	Alexander Stein <alexander.stein@ew.tq-group.com>,
	Fabio Estevam <festevam@denx.de>,
	linux-arm-kernel@lists.infradead.org,
	Mark Brown <broonie@kernel.org>,
	javier.carrasco@wolfvision.net
Subject: Re: [PATCH] ARM: multi_v7_defconfig: Select CONFIG_USB_ONBOARD_DEV as built-in
Date: Mon, 6 May 2024 14:54:12 +0000	[thread overview]
Message-ID: <ZjjvFIU1W4xgyRKu@google.com> (raw)
In-Reply-To: <CAOMZO5AwhUT-6ErqnCXd2P=u9cqYYaD5EFbnmsbY3AbcOQ6Q6A@mail.gmail.com>

On Fri, May 03, 2024 at 06:13:32PM -0300, Fabio Estevam wrote:
> On Fri, May 3, 2024 at 5:11 PM Matthias Kaehlcke <mka@chromium.org> wrote:
> 
> > Here are some debug logs from my side with CONFIG_USB_ONBOARD_DEV=m:
> >
> > [    0.755965] DBG: hub_probe: adding onboard pdevs
> > [    0.756204] DBG: hub_probe: done
> > [    0.756618] DBG: hub_probe: adding onboard pdevs
> > [    0.756621] DBG: hub_probe: done
> > [    8.094539] DBG: onboard_dev_init
> > [    9.141729] DBG: onboard_dev_probe
> > [    9.142237] DBG: onboard_dev_probe (done)
> > [    9.142428] DBG: onboard_dev_init (done)
> >
> > The root hub adds the onboard pdev at 0.75..., but the onboard_dev
> > module is only loaded more than 7s later (and probed even later). In
> > the meantime there are no errors of failed enumerations as seen on
> > the imx6q-udoo.
> 
> Thanks for investigating.
> 
> I haven't had a chance to extract these logs on the imx6q-udoo board yet.
> 
> > I wonder if the problem could be that the sense resistors of the hub
> > on the imx6q-udoo are always active and not only when the hub is
> > powered, indicating the controller the presence of a device, which
> > results in an attempt to enumerate it.
> 
> The  imx6q-udoo schematics are here:
> https://udoo.org/download/files/UDOO_QUAD-DUAL/schematics/UDOO_QUAD-DUAL_REV_D_schematics.pdf

There are no external pull-ups on USB_H1_DP/USB_H1_DN, maybe internal
pulls are enabled when the hub isn't powered?

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel