[PATCH v2 6/7] ACPICA: Events: Fix edge-triggered GPE by disabling before acknowledging it.

From: Lv Zheng
Date: Sat Jun 14 2014 - 20:42:47 EST


From: Lv Zheng <lv.zheng@xxxxxxxxx>

Due to ACPI specificiation 5, chapter 5.6.4 General-Purpose Event Hnadling,
OSPMs need to disable GPE before clearing the status bit for edge-triggered
GPEs.

Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx>
Tested-by: Gareth Williams <gareth@xxxxxxxxxxxxxxxxxxxx>
Tested-by: Steffen Weber <steffen.weber@xxxxxxxxx>
---
drivers/acpi/acpica/evgpe.c | 32 +++++++++++++++++---------------
1 file changed, 17 insertions(+), 15 deletions(-)

diff --git a/drivers/acpi/acpica/evgpe.c b/drivers/acpi/acpica/evgpe.c
index 48f7001..e4ba4de 100644
--- a/drivers/acpi/acpica/evgpe.c
+++ b/drivers/acpi/acpica/evgpe.c
@@ -698,21 +698,6 @@ acpi_ev_gpe_dispatch(struct acpi_namespace_node *gpe_device,
}

/*
- * If edge-triggered, clear the GPE status bit now. Note that
- * level-triggered events are cleared after the GPE is serviced.
- */
- if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
- ACPI_GPE_EDGE_TRIGGERED) {
- status = acpi_hw_clear_gpe(gpe_event_info);
- if (ACPI_FAILURE(status)) {
- ACPI_EXCEPTION((AE_INFO, status,
- "Unable to clear GPE %02X",
- gpe_number));
- return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
- }
- }
-
- /*
* Always disable the GPE so that it does not keep firing before
* any asynchronous activity completes (either from the execution
* of a GPE method or an asynchronous GPE handler.)
@@ -729,6 +714,23 @@ acpi_ev_gpe_dispatch(struct acpi_namespace_node *gpe_device,
}

/*
+ * If edge-triggered, clear the GPE status bit now. Note that
+ * level-triggered events are cleared after the GPE is serviced.
+ */
+ if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
+ ACPI_GPE_EDGE_TRIGGERED) {
+ status = acpi_hw_clear_gpe(gpe_event_info);
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status,
+ "Unable to clear GPE %02X",
+ gpe_number));
+ (void)acpi_hw_low_set_gpe(gpe_event_info,
+ ACPI_GPE_CONDITIONAL_ENABLE);
+ return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
+ }
+ }
+
+ /*
* Dispatch the GPE to either an installed handler or the control
* method associated with this GPE (_Lxx or _Exx). If a handler
* exists, we invoke it and do not attempt to run the method.
--
1.7.10

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