ACPI: EC: Handle IRQ storm on Acer laptops
On some Acer systems, the HW fails to clear the GPE source,
causing an interrupt storm.
So in EC interrupt mode, we count how many interrupts we
receive when waiting. If we get more than 5, we give
up on interrupt mode and revert to polling mode.
Also, for polling mode to work on Acers, we need
to insert a delay.
Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index caf873c..2c77359 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -129,6 +129,7 @@
struct mutex lock;
wait_queue_head_t wait;
struct list_head list;
+ atomic_t irq_count;
u8 handlers_installed;
} *boot_ec, *first_ec;
@@ -181,6 +182,8 @@
{
int ret = 0;
+ atomic_set(&ec->irq_count, 0);
+
if (unlikely(event == ACPI_EC_EVENT_OBF_1 &&
test_bit(EC_FLAGS_NO_OBF1_GPE, &ec->flags)))
force_poll = 1;
@@ -227,6 +230,7 @@
while (time_before(jiffies, delay)) {
if (acpi_ec_check_status(ec, event))
goto end;
+ msleep(5);
}
}
pr_err(PREFIX "acpi_ec_wait timeout,"
@@ -529,6 +533,13 @@
struct acpi_ec *ec = data;
pr_debug(PREFIX "~~~> interrupt\n");
+ atomic_inc(&ec->irq_count);
+ if (atomic_read(&ec->irq_count) > 5) {
+ pr_err(PREFIX "GPE storm detected, disabling EC GPE\n");
+ acpi_disable_gpe(NULL, ec->gpe, ACPI_ISR);
+ clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
+ return ACPI_INTERRUPT_HANDLED;
+ }
clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
wake_up(&ec->wait);