From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Boyd <stephen.boyd@linaro.org>
Subject: Re: [PATCH v3 09/12] EXAMPLE CODE: usb: port: Parse pwrseq phandle
 from Device Tree
Date: Thu, 02 Jun 2016 16:59:55 -0700
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Cc: Mark Rutland <mark.rutland@arm.com>, Krzysztof Kozlowski <k.kozlowski@samsung.com>, Ulf Hansson <ulf.hansson@linaro.org>, linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org, Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>, linux-pm@vger.kernel.org, Javier Martinez Canillas <javier@osg.samsung.com>, Kukjin Kim <kgene@kernel.org>, Alan Stern <stern@rowland.harvard.edu>, devicetree@vger.kernel.org, Pawel Moll <pawel.moll@arm.com>, Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>, Rob Herring <robh+dt@kernel.org>, linux-arm-kernel@lists.infradead.org, Ian Campbell <ijc+devicetree@hellion.org.uk>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, linux-usb@vger.kernel.org, linux-mmc@vger.kernel.org, Sebastian Reichel <sre@kernel.org>, Kumar Gala <galak@codeaurora.org>, David Woodhouse <dwmw2@infradead.org>
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Quoting Peter Chen (2016-06-01 18:24:19)
> On Wed, Jun 01, 2016 at 11:16:34AM -0700, Stephen Boyd wrote:
> > > 
> > > No, you may need to do reset before enumeration, the general purpose of
> > > reset is eliminate unstable hardware state, and let the controller find
> > > the device.
> > > 
> > > Try to do it at bootloader to see if it works for you.
> > > 
> > 
> > Sorry the bootloader doesn't do this so that doesn't work for me.
> 
> I mean try to see if the HUB can work if you reset it at bootloader.
> If it works, it means you need to do reset before enumeration, and you
> don't need to do anything after enumeration.
> 

Ah ok. Yes, I need to deassert the reset before enumeration. Right now I
have a driver for the 4604 hub controller that deasserts a reset gpio
and sends an i2c command to put the controller into "hub" mode. If I do
this before the usb controller driver probes then everything works. If I
do it after the controller probes it doesn't.