ACPICA: Events: Introduce acpi_mask_gpe() to implement GPE masking mechanism

ACPICA commit 23a417ca406a527e7ae1710893e59a8b6db30e14

There is a facility in Linux, developers can control the enabling/disabling
of a GPE via /sys/firmware/acpi/interrupts/gpexx. This is mainly for
debugging purposes.

But many users expect to use this facility to implement quirks to mask a
specific GPE when there is a gap in Linux causing this GPE to flood. This
is not working correctly because currently this facility invokes
enabling/disabling counting based GPE driver APIs:
 acpi_enable_gpe()/acpi_disable_gpe()
and the GPE drivers can still affect the count to mess up the GPE
masking purposes.

However, most of the IRQ chip designs allow masking/unmasking IRQs via a
masking bit which is different from the enabled bit to achieve the same
purpose. But the GPE hardware doesn't contain such a feature, this brings
the trouble.

In this patch, we introduce a software mechanism to implement the GPE
masking feature, and acpi_mask_gpe() are provided to the OSPMs to
mask/unmask GPEs in the above mentioned situation instead of
acpi_enable_gpe()/acpi_disable_gpe(). ACPICA BZ 1102. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/23a417ca
Link: https://bugs.acpica.org/show_bug.cgi?id=1102
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h
index 875964dea539..c2d4b9c9f8a4 100644
--- a/include/acpi/acpixf.h
+++ b/include/acpi/acpixf.h
@@ -736,6 +736,10 @@ ACPI_HW_DEPENDENT_RETURN_STATUS(acpi_status
 						u32 gpe_number))
 
 ACPI_HW_DEPENDENT_RETURN_STATUS(acpi_status
+				acpi_mask_gpe(acpi_handle gpe_device,
+					      u32 gpe_number, u8 is_masked))
+
+ACPI_HW_DEPENDENT_RETURN_STATUS(acpi_status
 				acpi_mark_gpe_for_wake(acpi_handle gpe_device,
 						       u32 gpe_number))