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Re: [PATCH v3 1/2] usb: host: ehci-tegra: Grab the correct UTMI pads reset

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On 05/04/2016 06:26 PM, Thierry Reding wrote:
> On Wed, May 04, 2016 at 07:57:10AM -0700, Greg Kroah-Hartman wrote:
>> On Wed, May 04, 2016 at 04:39:59PM +0200, Thierry Reding wrote:
>>> From: Thierry Reding <treding@nvidia.com>
>>>
>>> There are three EHCI controllers on Tegra SoCs, each with its own reset
>>> line. However, the first controller contains a set of UTMI configuration
>>> registers that are shared with its siblings. These registers will only
>>> be reset as part of the first controller's reset. For proper operation
>>> it must be ensured that the UTMI configuration registers are reset
>>> before any of the EHCI controllers are enabled, irrespective of the
>>> probe order.
>>>
>>> Commit a47cc24cd1e5 ("USB: EHCI: tegra: Fix probe order issue leading to
>>> broken USB") introduced code that ensures the first controller is always
>>> reset before setting up any of the controllers, and is never again reset
>>> afterwards.
>>>
>>> This code, however, grabs the wrong reset. Each EHCI controller has two
>>> reset controls attached: 1) the USB controller reset and 2) the UTMI
>>> pads reset (really the first controller's reset). In order to reset the
>>> UTMI pads registers the code must grab the second reset, but instead it
>>> grabbing the first.
>>>
>>> Signed-off-by: Thierry Reding <treding@nvidia.com>
...snip ...
>
> While at it, adding Tuomas who wrote the original probe order fix.
> Tuomas, does this patch look correct to you? Here's the patch in full if
> you don't have it in your inbox:
>
> 	http://patchwork.ozlabs.org/patch/618488/
>

D'oh! Yes, that patch looks correct.

- Tuomas

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[PATCH v3 1/2] usb: host: ehci-tegra: Grab the correct UTMI pads reset Thierry Reding <thierry.reding@gmail.com> - 2016-05-04 16:50 +0200
  Re: [PATCH v3 1/2] usb: host: ehci-tegra: Grab the correct UTMI pads  reset Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-04 17:00 +0200
    Re: [PATCH v3 1/2] usb: host: ehci-tegra: Grab the correct UTMI pads  reset Thierry Reding <thierry.reding@gmail.com> - 2016-05-04 17:30 +0200
      Re: [PATCH v3 1/2] usb: host: ehci-tegra: Grab the correct UTMI pads  reset Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi> - 2016-05-05 18:10 +0200
  Re: [PATCH v3 1/2] usb: host: ehci-tegra: Grab the correct UTMI pads  reset Stephen Warren <swarren@wwwdotorg.org> - 2016-05-04 19:20 +0200
    Re: [PATCH v3 1/2] usb: host: ehci-tegra: Grab the correct UTMI pads  reset Thierry Reding <thierry.reding@gmail.com> - 2016-05-04 22:40 +0200
  Re: [PATCH v3 1/2] usb: host: ehci-tegra: Grab the correct UTMI pads  reset Jon Hunter <jonathanh@nvidia.com> - 2016-05-05 09:40 +0200

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