Re: [PATCH v2] pinctrl: cherryview: Add support for GMMR GPIO opregion

[Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>]

On Wed, Mar 22, 2017 at 04:38:58PM +0100, Hans de Goede wrote:
> On some Cherry Trail devices the ASL uses the GMMR GPIO to access
> GPIOs so as to serialize MMIO accesses to GPIO registers with the
> OS, because:
> 
> "Due to a silicon issue, a shared lock must be used to prevent concurrent
> accesses across the 4 GPIO controllers.
> 
> See Intel Atom Z8000 Processor Series Specification Update (Rev. 005),
> errata #CHT34, for further information."
> 
> This commit adds support for this opregion, this fixes a number of
> ASL errors on my Ezpad mini3 tablet and makes the otg port device/host
> muxing which is controlled in firmware on this model work properly.
> 
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

Acked-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
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