ACPI: EC: Detect irq storm

Problem seems to be that hw fails to clear GPE after we service it and write 1
into corresponding bit. Thus, as soon as we get interrupts enabled again, we
receive a new one. Google gives too many results for "acer interrupt storm" for
this being one-broken-machine case.

Reference: http://bugzilla.kernel.org/show_bug.cgi?id=9998

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Alexey Starikovskiy 2008-03-21 19:36:02 +03:00 committed by Len Brown
parent 223883b7aa
commit fa95ba04e6
1 changed files with 11 additions and 0 deletions

View File

@ -106,6 +106,7 @@ static struct acpi_ec {
wait_queue_head_t wait;
struct list_head list;
struct delayed_work work;
atomic_t irq_count;
u8 handlers_installed;
} *boot_ec, *first_ec;
@ -171,6 +172,7 @@ static void ec_switch_to_poll_mode(struct acpi_ec *ec)
static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll)
{
atomic_set(&ec->irq_count, 0);
if (likely(test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) &&
likely(!force_poll)) {
if (wait_event_timeout(ec->wait, acpi_ec_check_status(ec, event),
@ -489,6 +491,12 @@ static u32 acpi_ec_gpe_handler(void *data)
u8 state = acpi_ec_read_status(ec);
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");
ec_switch_to_poll_mode(ec);
goto end;
}
clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
wake_up(&ec->wait);
@ -507,6 +515,7 @@ static u32 acpi_ec_gpe_handler(void *data)
set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
clear_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
}
end:
ec_schedule_ec_poll(ec);
return ACPI_SUCCESS(status) ?
ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
@ -515,6 +524,7 @@ static u32 acpi_ec_gpe_handler(void *data)
static void do_ec_poll(struct work_struct *work)
{
struct acpi_ec *ec = container_of(work, struct acpi_ec, work.work);
atomic_set(&ec->irq_count, 0);
(void)acpi_ec_gpe_handler(ec);
}
@ -679,6 +689,7 @@ static struct acpi_ec *make_acpi_ec(void)
init_waitqueue_head(&ec->wait);
INIT_LIST_HEAD(&ec->list);
INIT_DELAYED_WORK_DEFERRABLE(&ec->work, do_ec_poll);
atomic_set(&ec->irq_count, 0);
return ec;
}