sc7180: Cancel the power button timer during the power state transition

A timer is created in the check_for_power_off_event(), which waits for
the power button long press. Should cancel the timer during the power
state transition; otherwise, EC will crash.

The S3 state calls the check_for_power_off_event() too. So cancel the
timer during S3->S0 and S3->S5.

BRANCH=None
BUG=b:163367454
TEST=Checked the bug scenario:
 * In VT2, run powerd_dbus_suspend and EC transits the state to S3.
 * Press power button
 * EC transits the state to S0; no crash.
TEST=Tested the normal shutdown case:
 * Hold the power button
 * After 8s, EC transits to S3 and then S5 after the power button is
   released.
TEST=Tested the change in check_for_power_off_event():
 * Hold the power button
 * In VT2, run "shutdown -H now" which makes POWER_GOOD drop
 * EC transits to S3 and then S5 after the power button is released

Change-Id: Ia279e890954cf77f94ae8907a2782f94265c849a
Signed-off-by: Wai-Hong Tam <waihong@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2346600
Reviewed-by: Stephen Boyd <swboyd@chromium.org>

1 files changed, 18 insertions, 9 deletions

diff --git a/power/sc7180.c b/power/sc7180.c
index aa62c20ca2..77c3a3e7f1 100644
--- a/power/sc7180.c
+++ b/power/sc7180.c
@@ -743,9 +743,6 @@ static uint8_t check_for_power_off_event(void)
 
 	/* POWER_GOOD released by AP : shutdown immediately */
 	if (!power_has_signals(IN_POWER_GOOD)) {
-		if (power_button_was_pressed)
-			timer_cancel(TASK_ID_CHIPSET);
-
 		CPRINTS("POWER_GOOD is lost");
 		return POWER_OFF_BY_POWER_GOOD_LOST;
 	}
@@ -753,6 +750,19 @@ static uint8_t check_for_power_off_event(void)
 	return POWER_OFF_CANCEL;
 }
 
+/**
+ * Cancel the power button timer.
+ *
+ * The timer was previously created in the check_for_power_off_event(),
+ * which waited for the power button long press. Should cancel the timer
+ * during the power state transition; otherwise, EC will crash.
+ */
+static inline void cancel_power_button_timer(void)
+{
+	if (power_button_was_pressed)
+		timer_cancel(TASK_ID_CHIPSET);
+}
+
 /*****************************************************************************/
 /* Chipset interface */
 
@@ -989,6 +999,8 @@ enum power_state power_handle_state(enum power_state state)
 		break;
 
 	case POWER_S3S0:
+		cancel_power_button_timer();
+
 #ifdef CONFIG_CHIPSET_RESUME_INIT_HOOK
 		/*
 		 * Notify the RESUME_INIT hooks, i.e. enabling SPI driver
@@ -1019,12 +1031,7 @@ enum power_state power_handle_state(enum power_state state)
 		break;
 
 	case POWER_S0S3:
-		/*
-		 * If the power button is pressing, we need cancel the long
-		 * press timer, otherwise EC will crash.
-		 */
-		if (power_button_was_pressed)
-			timer_cancel(TASK_ID_CHIPSET);
+		cancel_power_button_timer();
 
 #ifdef CONFIG_CHIPSET_RESUME_INIT_HOOK
 		/*
@@ -1048,6 +1055,8 @@ enum power_state power_handle_state(enum power_state state)
 		return POWER_S3;
 
 	case POWER_S3S5:
+		cancel_power_button_timer();
+
 		/* Call hooks before we drop power rails */
 		hook_notify(HOOK_CHIPSET_SHUTDOWN);