1 files changed, 68 insertions, 48 deletions

diff --git a/drivers/power/apm_power.c b/drivers/power/apm_power.c
index bbf3ee10da04..7e29b90a4f63 100644
--- a/drivers/power/apm_power.c
+++ b/drivers/power/apm_power.c
@@ -13,6 +13,7 @@
 #include <linux/power_supply.h>
 #include <linux/apm-emulation.h>
 
+static DEFINE_MUTEX(apm_mutex);
 #define PSY_PROP(psy, prop, val) psy->get_property(psy, \
                          POWER_SUPPLY_PROP_##prop, val)
 
@@ -23,67 +24,86 @@
 
 static struct power_supply *main_battery;
 
-static void find_main_battery(void)
-{
-        struct device *dev;
-        struct power_supply *bat = NULL;
-        struct power_supply *max_charge_bat = NULL;
-        struct power_supply *max_energy_bat = NULL;
+struct find_bat_param {
+        struct power_supply *main;
+        struct power_supply *bat;
+        struct power_supply *max_charge_bat;
+        struct power_supply *max_energy_bat;
         union power_supply_propval full;
-        int max_charge = 0;
-        int max_energy = 0;
+        int max_charge;
+        int max_energy;
+};
 
-        main_battery = NULL;
+static int __find_main_battery(struct device *dev, void *data)
+{
+        struct find_bat_param *bp = (struct find_bat_param *)data;
 
-        list_for_each_entry(dev, &power_supply_class->devices, node) {
-                bat = dev_get_drvdata(dev);
+        bp->bat = dev_get_drvdata(dev);
 
-                if (bat->use_for_apm) {
-                        /* nice, we explicitly asked to report this battery. */
-                        main_battery = bat;
-                        return;
-                }
+        if (bp->bat->use_for_apm) {
+                /* nice, we explicitly asked to report this battery. */
+                bp->main = bp->bat;
+                return 1;
+        }
 
-                if (!PSY_PROP(bat, CHARGE_FULL_DESIGN, &full) ||
-                                !PSY_PROP(bat, CHARGE_FULL, &full)) {
-                        if (full.intval > max_charge) {
-                                max_charge_bat = bat;
-                                max_charge = full.intval;
-                        }
-                } else if (!PSY_PROP(bat, ENERGY_FULL_DESIGN, &full) ||
-                                !PSY_PROP(bat, ENERGY_FULL, &full)) {
-                        if (full.intval > max_energy) {
-                                max_energy_bat = bat;
-                                max_energy = full.intval;
-                        }
+        if (!PSY_PROP(bp->bat, CHARGE_FULL_DESIGN, &bp->full) ||
+                        !PSY_PROP(bp->bat, CHARGE_FULL, &bp->full)) {
+                if (bp->full.intval > bp->max_charge) {
+                        bp->max_charge_bat = bp->bat;
+                        bp->max_charge = bp->full.intval;
+                }
+        } else if (!PSY_PROP(bp->bat, ENERGY_FULL_DESIGN, &bp->full) ||
+                        !PSY_PROP(bp->bat, ENERGY_FULL, &bp->full)) {
+                if (bp->full.intval > bp->max_energy) {
+                        bp->max_energy_bat = bp->bat;
+                        bp->max_energy = bp->full.intval;
                 }
         }
+        return 0;
+}
+
+static void find_main_battery(void)
+{
+        struct find_bat_param bp;
+        int error;
+
+        memset(&bp, 0, sizeof(struct find_bat_param));
+        main_battery = NULL;
+        bp.main = main_battery;
+
+        error = class_for_each_device(power_supply_class, &bp,
+                                      __find_main_battery);
+        if (error) {
+                main_battery = bp.main;
+                return;
+        }
 
-        if ((max_energy_bat && max_charge_bat) &&
-                        (max_energy_bat != max_charge_bat)) {
+        if ((bp.max_energy_bat && bp.max_charge_bat) &&
+                        (bp.max_energy_bat != bp.max_charge_bat)) {
                 /* try guess battery with more capacity */
-                if (!PSY_PROP(max_charge_bat, VOLTAGE_MAX_DESIGN, &full)) {
-                        if (max_energy > max_charge * full.intval)
-                                main_battery = max_energy_bat;
+                if (!PSY_PROP(bp.max_charge_bat, VOLTAGE_MAX_DESIGN,
+                              &bp.full)) {
+                        if (bp.max_energy > bp.max_charge * bp.full.intval)
+                                main_battery = bp.max_energy_bat;
                         else
-                                main_battery = max_charge_bat;
-                } else if (!PSY_PROP(max_energy_bat, VOLTAGE_MAX_DESIGN,
-                                                                  &full)) {
-                        if (max_charge > max_energy / full.intval)
-                                main_battery = max_charge_bat;
+                                main_battery = bp.max_charge_bat;
+                } else if (!PSY_PROP(bp.max_energy_bat, VOLTAGE_MAX_DESIGN,
+                                                                  &bp.full)) {
+                        if (bp.max_charge > bp.max_energy / bp.full.intval)
+                                main_battery = bp.max_charge_bat;
                         else
-                                main_battery = max_energy_bat;
+                                main_battery = bp.max_energy_bat;
                 } else {
                         /* give up, choice any */
-                        main_battery = max_energy_bat;
+                        main_battery = bp.max_energy_bat;
                 }
-        } else if (max_charge_bat) {
-                main_battery = max_charge_bat;
-        } else if (max_energy_bat) {
-                main_battery = max_energy_bat;
+        } else if (bp.max_charge_bat) {
+                main_battery = bp.max_charge_bat;
+        } else if (bp.max_energy_bat) {
+                main_battery = bp.max_energy_bat;
         } else {
                 /* give up, try the last if any */
-                main_battery = bat;
+                main_battery = bp.bat;
         }
 }
 
@@ -207,10 +227,10 @@ static void apm_battery_apm_get_power_status(struct apm_power_info *info)
         union power_supply_propval status;
         union power_supply_propval capacity, time_to_full, time_to_empty;
 
-        down(&power_supply_class->sem);
+        mutex_lock(&apm_mutex);
         find_main_battery();
         if (!main_battery) {
-                up(&power_supply_class->sem);
+                mutex_unlock(&apm_mutex);
                 return;
         }
 
@@ -278,7 +298,7 @@ static void apm_battery_apm_get_power_status(struct apm_power_info *info)
                 }
         }
 
-        up(&power_supply_class->sem);
+        mutex_unlock(&apm_mutex);
 }
 
 static int __init apm_battery_init(void)