This patch tries to detect EC events earlier after resume, so that if an
event occurred before invoking acpi_ec_unblock_transactions(), it could be
detected by acpi_ec_unblock_transactions() which is the earliest EC driver
call after resume.
However after the noirq stage, if an event ocurred after
acpi_ec_unblock_transactions() and before acpi_ec_resume(), there was no
mean to detect and trigger it right then, but can only detect it and handle
it after acpi_ec_resume().
Now the final logic is:
1. If ec_freeze_events=Y, event handling is stopped in acpi_ec_suspend(),
restarted in acpi_ec_resume();
2. If ec_freeze_events=N, event handling is stopped in
acpi_ec_block_transactions(), restarted in
acpi_ec_unblock_transactions();
3. In order to handling the conflict of the edge-trigger nature of EC IRQ
and the Linux noirq stage, advance_transaction() is invoked where the
event handling is enabled and the noirq stage is ended.
Known issue:
1. Event ocurred between acpi_ec_unblock_transactions() and
acpi_ec_resume() may still lead to the order issue. This can only be
fixed by adding a periodic detection mechanism during the noirq stage.
Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx>
Tested-by: Tomislav Ivek <tomislav.ivek@xxxxxxxxx>
Tested-by: Luya Tshimbalanga <luya@xxxxxxxxxxxxxxxxx>
---
drivers/acpi/ec.c | 35 ++++++++++++++++++++++++++---------
1 file changed, 26 insertions(+), 9 deletions(-)
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index df84246..f1f320b 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -249,6 +249,11 @@ static bool acpi_ec_started(struct acpi_ec *ec)
!test_bit(EC_FLAGS_STOPPED, &ec->flags);
}
+static bool acpi_ec_no_sleep_events(void)
+{
+ return acpi_sleep_no_ec_events() && ec_freeze_events;
+}
+
static bool acpi_ec_event_enabled(struct acpi_ec *ec)
{
/*
@@ -260,14 +265,14 @@ static bool acpi_ec_event_enabled(struct acpi_ec *ec)
return false;
/*
* However, disabling the event handling is experimental for late
- * stage (suspend), and is controlled by the boot parameter of
- * "ec_freeze_events":
+ * stage (suspend), and is controlled by
+ * "acpi_ec_no_sleep_events()":
* 1. true: The EC event handling is disabled before entering
* the noirq stage.
* 2. false: The EC event handling is automatically disabled as
* soon as the EC driver is stopped.
*/
- if (ec_freeze_events)
+ if (acpi_ec_no_sleep_events())
return acpi_ec_started(ec);
else
return test_bit(EC_FLAGS_STARTED, &ec->flags);
@@ -524,8 +529,8 @@ static bool acpi_ec_query_flushed(struct acpi_ec *ec)
static void __acpi_ec_flush_event(struct acpi_ec *ec)
{
/*
- * When ec_freeze_events is true, we need to flush events in
- * the proper position before entering the noirq stage.
+ * When acpi_ec_no_sleep_events() is true, we need to flush events
+ * in the proper position before entering the noirq stage.
*/
wait_event(ec->wait, acpi_ec_query_flushed(ec));
if (ec_query_wq)
@@ -948,7 +953,8 @@ static void acpi_ec_start(struct acpi_ec *ec, bool resuming)
if (!resuming) {
acpi_ec_submit_request(ec);
ec_dbg_ref(ec, "Increase driver");
- }
+ } else if (!acpi_ec_no_sleep_events())
+ __acpi_ec_enable_event(ec);
ec_log_drv("EC started");
}
spin_unlock_irqrestore(&ec->lock, flags);
@@ -980,7 +986,7 @@ static void acpi_ec_stop(struct acpi_ec *ec, bool suspending)
if (!suspending) {
acpi_ec_complete_request(ec);
ec_dbg_ref(ec, "Decrease driver");
- } else if (!ec_freeze_events)
+ } else if (!acpi_ec_no_sleep_events())
__acpi_ec_disable_event(ec);
clear_bit(EC_FLAGS_STARTED, &ec->flags);
clear_bit(EC_FLAGS_STOPPED, &ec->flags);
@@ -1910,7 +1916,7 @@ static int acpi_ec_suspend(struct device *dev)
struct acpi_ec *ec =
acpi_driver_data(to_acpi_device(dev));
- if (acpi_sleep_no_ec_events() && ec_freeze_events)
+ if (acpi_ec_no_sleep_events())
acpi_ec_disable_event(ec);
return 0;
}
@@ -1946,7 +1952,18 @@ static int acpi_ec_resume(struct device *dev)
struct acpi_ec *ec =
acpi_driver_data(to_acpi_device(dev));
- acpi_ec_enable_event(ec);
+ if (acpi_ec_no_sleep_events())
+ acpi_ec_enable_event(ec);
+ else {
+ /*
+ * Though whether there is an event pending has been
+ * checked in acpi_ec_unblock_transactions() when
+ * acpi_ec_no_sleep_events() is false, check it one more
+ * time after noirq stage to detect events occurred after
+ * acpi_ec_unblock_transactions().
+ */
+ advance_transaction(ec);
+ }
return 0;
}
#endif
--
2.7.4
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