ACPI: AC: Update AC state on sysfs read

From: Alexey Starikovskiy <astarikovskiy@suse.de>

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
---

 drivers/acpi/ac.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/acpi/ac.c b/drivers/acpi/ac.c
index e03de37..bb618c8 100644
--- a/drivers/acpi/ac.c
+++ b/drivers/acpi/ac.c
@@ -91,6 +91,9 @@ static int get_ac_property(struct power_supply *psy,
 			   union power_supply_propval *val)
 {
 	struct acpi_ac *ac = to_acpi_ac(psy);
+
+	if (acpi_ac_get_state(ac))
+		return 0;
 	switch (psp) {
 	case POWER_SUPPLY_PROP_ONLINE:
 		val->intval = ac->state;