1 files changed, 54 insertions, 32 deletions

diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 2c661353e8f2..7711d94a0409 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -55,6 +55,9 @@
 #define ACPI_BATTERY_NOTIFY_INFO        0x81
 #define ACPI_BATTERY_NOTIFY_THRESHOLD   0x82
 
+/* Battery power unit: 0 means mW, 1 means mA */
+#define ACPI_BATTERY_POWER_UNIT_MA      1
+
 #define _COMPONENT              ACPI_BATTERY_COMPONENT
 
 ACPI_MODULE_NAME("battery");
@@ -91,16 +94,12 @@ MODULE_DEVICE_TABLE(acpi, battery_device_ids);
 enum {
         ACPI_BATTERY_ALARM_PRESENT,
         ACPI_BATTERY_XINFO_PRESENT,
-        /* For buggy DSDTs that report negative 16-bit values for either
-         * charging or discharging current and/or report 0 as 65536
-         * due to bad math.
-         */
-        ACPI_BATTERY_QUIRK_SIGNED16_CURRENT,
         ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY,
 };
 
 struct acpi_battery {
         struct mutex lock;
+        struct mutex sysfs_lock;
         struct power_supply bat;
         struct acpi_device *device;
         struct notifier_block pm_nb;
@@ -301,7 +300,8 @@ static enum power_supply_property energy_battery_props[] = {
 #ifdef CONFIG_ACPI_PROCFS_POWER
 inline char *acpi_battery_units(struct acpi_battery *battery)
 {
-        return (battery->power_unit)?"mA":"mW";
+        return (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA) ?
+                "mA" : "mW";
 }
 #endif
 
@@ -461,9 +461,17 @@ static int acpi_battery_get_state(struct acpi_battery *battery)
         battery->update_time = jiffies;
         kfree(buffer.pointer);
 
-        if (test_bit(ACPI_BATTERY_QUIRK_SIGNED16_CURRENT, &battery->flags) &&
-            battery->rate_now != -1)
+        /* For buggy DSDTs that report negative 16-bit values for either
+         * charging or discharging current and/or report 0 as 65536
+         * due to bad math.
+         */
+        if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA &&
+                battery->rate_now != ACPI_BATTERY_VALUE_UNKNOWN &&
+                (s16)(battery->rate_now) < 0) {
                 battery->rate_now = abs((s16)battery->rate_now);
+                printk_once(KERN_WARNING FW_BUG "battery: (dis)charge rate"
+                        " invalid.\n");
+        }
 
         if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags)
             && battery->capacity_now >= 0 && battery->capacity_now <= 100)
@@ -544,7 +552,7 @@ static int sysfs_add_battery(struct acpi_battery *battery)
 {
         int result;
 
-        if (battery->power_unit) {
+        if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA) {
                 battery->bat.properties = charge_battery_props;
                 battery->bat.num_properties =
                         ARRAY_SIZE(charge_battery_props);
@@ -566,18 +574,16 @@ static int sysfs_add_battery(struct acpi_battery *battery)
 
 static void sysfs_remove_battery(struct acpi_battery *battery)
 {
-        if (!battery->bat.dev)
+        mutex_lock(&battery->sysfs_lock);
+        if (!battery->bat.dev) {
+                mutex_unlock(&battery->sysfs_lock);
                 return;
+        }
+
         device_remove_file(battery->bat.dev, &alarm_attr);
         power_supply_unregister(&battery->bat);
         battery->bat.dev = NULL;
-}
-
-static void acpi_battery_quirks(struct acpi_battery *battery)
-{
-        if (dmi_name_in_vendors("Acer") && battery->power_unit) {
-                set_bit(ACPI_BATTERY_QUIRK_SIGNED16_CURRENT, &battery->flags);
-        }
+        mutex_unlock(&battery->sysfs_lock);
 }
 
 /*
@@ -592,7 +598,7 @@ static void acpi_battery_quirks(struct acpi_battery *battery)
  *
  * Handle this correctly so that they won't break userspace.
  */
-static void acpi_battery_quirks2(struct acpi_battery *battery)
+static void acpi_battery_quirks(struct acpi_battery *battery)
 {
         if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
                 return ;
@@ -623,13 +629,15 @@ static int acpi_battery_update(struct acpi_battery *battery)
                 result = acpi_battery_get_info(battery);
                 if (result)
                         return result;
-                acpi_battery_quirks(battery);
                 acpi_battery_init_alarm(battery);
         }
-        if (!battery->bat.dev)
-                sysfs_add_battery(battery);
+        if (!battery->bat.dev) {
+                result = sysfs_add_battery(battery);
+                if (result)
+                        return result;
+        }
         result = acpi_battery_get_state(battery);
-        acpi_battery_quirks2(battery);
+        acpi_battery_quirks(battery);
         return result;
 }
 
@@ -863,7 +871,7 @@ DECLARE_FILE_FUNCTIONS(alarm);
                 }, \
         }
 
-static struct battery_file {
+static const struct battery_file {
         struct file_operations ops;
         mode_t mode;
         const char *name;
@@ -948,9 +956,12 @@ static int battery_notify(struct notifier_block *nb,
         struct acpi_battery *battery = container_of(nb, struct acpi_battery,
                                                     pm_nb);
         switch (mode) {
+        case PM_POST_HIBERNATION:
         case PM_POST_SUSPEND:
-                sysfs_remove_battery(battery);
-                sysfs_add_battery(battery);
+                if (battery->bat.dev) {
+                        sysfs_remove_battery(battery);
+                        sysfs_add_battery(battery);
+                }
                 break;
         }
 
@@ -972,28 +983,38 @@ static int acpi_battery_add(struct acpi_device *device)
         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
         device->driver_data = battery;
         mutex_init(&battery->lock);
+        mutex_init(&battery->sysfs_lock);
         if (ACPI_SUCCESS(acpi_get_handle(battery->device->handle,
                         "_BIX", &handle)))
                 set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
-        acpi_battery_update(battery);
+        result = acpi_battery_update(battery);
+        if (result)
+                goto fail;
 #ifdef CONFIG_ACPI_PROCFS_POWER
         result = acpi_battery_add_fs(device);
 #endif
-        if (!result) {
-                printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
-                        ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
-                        device->status.battery_present ? "present" : "absent");
-        } else {
+        if (result) {
 #ifdef CONFIG_ACPI_PROCFS_POWER
                 acpi_battery_remove_fs(device);
 #endif
-                kfree(battery);
+                goto fail;
         }
 
+        printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
+                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
+                device->status.battery_present ? "present" : "absent");
+
         battery->pm_nb.notifier_call = battery_notify;
         register_pm_notifier(&battery->pm_nb);
 
         return result;
+
+fail:
+        sysfs_remove_battery(battery);
+        mutex_destroy(&battery->lock);
+        mutex_destroy(&battery->sysfs_lock);
+        kfree(battery);
+        return result;
 }
 
 static int acpi_battery_remove(struct acpi_device *device, int type)
@@ -1009,6 +1030,7 @@ static int acpi_battery_remove(struct acpi_device *device, int type)
 #endif
         sysfs_remove_battery(battery);
         mutex_destroy(&battery->lock);
+        mutex_destroy(&battery->sysfs_lock);
         kfree(battery);
         return 0;
 }