Hi,
On 22-03-17 18:00, Andy Shevchenko wrote:
On Wed, 2017-03-22 at 16:38 +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>
+static acpi_status chv_pinctrl_mmio_access_handler(u32 function,
+ acpi_physical_address address, u32 bits, u64 *value,
+ void *handler_context, void *region_context)
+{
+ struct chv_pinctrl *pctrl = region_context;
+ unsigned long flags;
+ acpi_status ret = AE_OK;
+
+ raw_spin_lock_irqsave(&chv_lock, flags);
+
+ if (function == ACPI_WRITE)
+ chv_writel((u32)(*value), pctrl->regs +
(u32)address);
+ else if (function == ACPI_READ)
+ *value = readl(pctrl->regs + (u32)address);
+ else
+ ret = AE_BAD_PARAMETER;
+
+ raw_spin_unlock_irqrestore(&chv_lock, flags);
+
+ return AE_OK;
return ret;
Didn't notice before, sorry.
No problem, v3 coming up.
Regards,
Hans
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