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@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>