1 files changed, 50 insertions, 32 deletions

diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index fcc13ac0aa18..52720680190f 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");
@@ -91,11 +94,6 @@ 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,
 };
 
@@ -301,7 +299,8 @@ 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 +460,17 @@ 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 +551,7 @@ 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 +573,16 @@ 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->lock);
+	if (!battery->bat.dev) {
+		mutex_unlock(&battery->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->lock);
 }
 
 /*
@@ -592,7 +597,7 @@ 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 +628,15 @@ 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 +870,7 @@ 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 +955,12 @@ 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;
 	}
 
@@ -975,25 +985,33 @@ static int acpi_battery_add(struct acpi_device *device)
 	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);
+	kfree(battery);
+	return result;
 }
 
 static int acpi_battery_remove(struct acpi_device *device, int type)