ACPI: battery: register power_supply subdevice only when battery is present

Make sure no power_supply object is present unless we actualy detect
presence of battery. This fixes ghost batteries detected by HAL

Signed-off-by: Andrey Borzenkov <arvidjaar@mail.ru>
Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 75 insertions, 55 deletions

diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 9da8cec80fd1..489d3385efe4 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -388,29 +388,81 @@ static int acpi_battery_init_alarm(struct acpi_battery *battery)
         return acpi_battery_set_alarm(battery);
 }
 
+static ssize_t acpi_battery_alarm_show(struct device *dev,
+                                        struct device_attribute *attr,
+                                        char *buf)
+{
+        struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
+        return sprintf(buf, "%d\n", battery->alarm * 1000);
+}
+
+static ssize_t acpi_battery_alarm_store(struct device *dev,
+                                        struct device_attribute *attr,
+                                        const char *buf, size_t count)
+{
+        unsigned long x;
+        struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
+        if (sscanf(buf, "%ld\n", &x) == 1)
+                battery->alarm = x/1000;
+        if (acpi_battery_present(battery))
+                acpi_battery_set_alarm(battery);
+        return count;
+}
+
+static struct device_attribute alarm_attr = {
+        .attr = {.name = "alarm", .mode = 0644, .owner = THIS_MODULE},
+        .show = acpi_battery_alarm_show,
+        .store = acpi_battery_alarm_store,
+};
+
+static int sysfs_add_battery(struct acpi_battery *battery)
+{
+        int result;
+
+        battery->update_time = 0;
+        result = acpi_battery_get_info(battery);
+        acpi_battery_init_alarm(battery);
+        if (result)
+                return result;
+        if (battery->power_unit) {
+                battery->bat.properties = charge_battery_props;
+                battery->bat.num_properties =
+                        ARRAY_SIZE(charge_battery_props);
+        } else {
+                battery->bat.properties = energy_battery_props;
+                battery->bat.num_properties =
+                        ARRAY_SIZE(energy_battery_props);
+        }
+
+        battery->bat.name = acpi_device_bid(battery->device);
+        battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
+        battery->bat.get_property = acpi_battery_get_property;
+
+        result = power_supply_register(&battery->device->dev, &battery->bat);
+        if (result)
+                return result;
+        return device_create_file(battery->bat.dev, &alarm_attr);
+}
+
+static void sysfs_remove_battery(struct acpi_battery *battery)
+{
+        if (!battery->bat.dev)
+                return;
+        device_remove_file(battery->bat.dev, &alarm_attr);
+        power_supply_unregister(&battery->bat);
+}
+
 static int acpi_battery_update(struct acpi_battery *battery)
 {
-        int saved_present = acpi_battery_present(battery);
         int result = acpi_battery_get_status(battery);
-        if (result || !acpi_battery_present(battery))
+        if (result)
                 return result;
-        if (saved_present != acpi_battery_present(battery) ||
-            !battery->update_time) {
-                battery->update_time = 0;
-                result = acpi_battery_get_info(battery);
-                if (result)
-                        return result;
-                if (battery->power_unit) {
-                        battery->bat.properties = charge_battery_props;
-                        battery->bat.num_properties =
-                                ARRAY_SIZE(charge_battery_props);
-                } else {
-                        battery->bat.properties = energy_battery_props;
-                        battery->bat.num_properties =
-                                ARRAY_SIZE(energy_battery_props);
-                }
-                acpi_battery_init_alarm(battery);
+        if (!acpi_battery_present(battery)) {
+                sysfs_remove_battery(battery);
+                return 0;
         }
+        if (!battery->bat.dev)
+                sysfs_add_battery(battery);
         return acpi_battery_get_state(battery);
 }
 
@@ -687,33 +739,6 @@ static void acpi_battery_remove_fs(struct acpi_device *device)
 
 #endif
 
-static ssize_t acpi_battery_alarm_show(struct device *dev,
-                                        struct device_attribute *attr,
-                                        char *buf)
-{
-        struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
-        return sprintf(buf, "%d\n", battery->alarm * 1000);
-}
-
-static ssize_t acpi_battery_alarm_store(struct device *dev,
-                                        struct device_attribute *attr,
-                                        const char *buf, size_t count)
-{
-        unsigned long x;
-        struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
-        if (sscanf(buf, "%ld\n", &x) == 1)
-                battery->alarm = x/1000;
-        if (acpi_battery_present(battery))
-                acpi_battery_set_alarm(battery);
-        return count;
-}
-
-static struct device_attribute alarm_attr = {
-        .attr = {.name = "alarm", .mode = 0644, .owner = THIS_MODULE},
-        .show = acpi_battery_alarm_show,
-        .store = acpi_battery_alarm_store,
-};
-
 /* --------------------------------------------------------------------------
                                  Driver Interface
    -------------------------------------------------------------------------- */
@@ -731,7 +756,9 @@ static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
         acpi_bus_generate_netlink_event(device->pnp.device_class,
                                         device->dev.bus_id, event,
                                         acpi_battery_present(battery));
-        kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
+        /* acpi_batter_update could remove power_supply object */
+        if (battery->bat.dev)
+                kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
 }
 
 static int acpi_battery_add(struct acpi_device *device)
@@ -755,11 +782,6 @@ static int acpi_battery_add(struct acpi_device *device)
         if (result)
                 goto end;
 #endif
-        battery->bat.name = acpi_device_bid(device);
-        battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
-        battery->bat.get_property = acpi_battery_get_property;
-        result = power_supply_register(&battery->device->dev, &battery->bat);
-        result = device_create_file(battery->bat.dev, &alarm_attr);
         status = acpi_install_notify_handler(device->handle,
                                              ACPI_ALL_NOTIFY,
                                              acpi_battery_notify, battery);
@@ -795,10 +817,7 @@ static int acpi_battery_remove(struct acpi_device *device, int type)
 #ifdef CONFIG_ACPI_PROCFS
         acpi_battery_remove_fs(device);
 #endif
-        if (battery->bat.dev) {
-                device_remove_file(battery->bat.dev, &alarm_attr);
-                power_supply_unregister(&battery->bat);
-        }
+        sysfs_remove_battery(battery);
         mutex_destroy(&battery->lock);
         kfree(battery);
         return 0;
@@ -812,6 +831,7 @@ static int acpi_battery_resume(struct acpi_device *device)
                 return -EINVAL;
         battery = acpi_driver_data(device);
         battery->update_time = 0;
+        acpi_battery_update(battery);
         return 0;
 }