[PATCH] ACPI: Battery: remove cycle from battery removal.

[Alexey Starikovskiy <astarikovskiy@suse.de>]

get_property() should not call battery_update() on absent battery to
avoid cycle and oops.

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Tested-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
---

 drivers/acpi/battery.c |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index c2ce0ad..ca37db4 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -140,10 +140,11 @@ static int acpi_battery_get_property(struct power_supply *psy,
 {
 	struct acpi_battery *battery = to_acpi_battery(psy);
 
-	if ((!acpi_battery_present(battery)) &&
-	     psp != POWER_SUPPLY_PROP_PRESENT)
+	if (acpi_battery_present(battery)) {
+		/* run battery update only if it is present */
+		acpi_battery_update(battery);
+	} else if (psp != POWER_SUPPLY_PROP_PRESENT)
 		return -ENODEV;
-	acpi_battery_update(battery);
 	switch (psp) {
 	case POWER_SUPPLY_PROP_STATUS:
 		if (battery->state & 0x01)
@@ -457,6 +458,7 @@ static void sysfs_remove_battery(struct acpi_battery *battery)
 		return;
 	device_remove_file(battery->bat.dev, &alarm_attr);
 	power_supply_unregister(&battery->bat);
+	battery->bat.dev = NULL;
 }
 
 static int acpi_battery_update(struct acpi_battery *battery)