apm_power: check I.intval for zero value, we use it as the divisor
[sfrench/cifs-2.6.git] / drivers / power / apm_power.c
index 3928e7cdddc13331c5176491df1f7891896cc4fb..a4892275659dc02ffb1d12b85d0774a86bda8b08 100644 (file)
@@ -13,6 +13,7 @@
 #include <linux/power_supply.h>
 #include <linux/apm-emulation.h>
 
+
 #define PSY_PROP(psy, prop, val) psy->get_property(psy, \
                         POWER_SUPPLY_PROP_##prop, val)
 
 
 #define MPSY_PROP(prop, val) _MPSY_PROP(POWER_SUPPLY_PROP_##prop, val)
 
+static DEFINE_MUTEX(apm_mutex);
 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;
+enum apm_source {
+       SOURCE_ENERGY,
+       SOURCE_CHARGE,
+       SOURCE_VOLTAGE,
+};
+
+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;
 
-       if ((max_energy_bat && max_charge_bat) &&
-                       (max_energy_bat != max_charge_bat)) {
+       error = class_for_each_device(power_supply_class, &bp,
+                                     __find_main_battery);
+       if (error) {
+               main_battery = bp.main;
+               return;
+       }
+
+       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;
        }
 }
 
-static int calculate_time(int status)
+static int do_calculate_time(int status, enum apm_source source)
 {
-       union power_supply_propval charge_full, charge_empty;
-       union power_supply_propval charge, I;
+       union power_supply_propval full;
+       union power_supply_propval empty;
+       union power_supply_propval cur;
+       union power_supply_propval I;
+       enum power_supply_property full_prop;
+       enum power_supply_property full_design_prop;
+       enum power_supply_property empty_prop;
+       enum power_supply_property empty_design_prop;
+       enum power_supply_property cur_avg_prop;
+       enum power_supply_property cur_now_prop;
 
-       if (MPSY_PROP(CHARGE_FULL, &charge_full)) {
-               /* if battery can't report this property, use design value */
-               if (MPSY_PROP(CHARGE_FULL_DESIGN, &charge_full))
+       if (MPSY_PROP(CURRENT_AVG, &I)) {
+               /* if battery can't report average value, use momentary */
+               if (MPSY_PROP(CURRENT_NOW, &I))
                        return -1;
        }
 
-       if (MPSY_PROP(CHARGE_EMPTY, &charge_empty)) {
-               /* if battery can't report this property, use design value */
-               if (MPSY_PROP(CHARGE_EMPTY_DESIGN, &charge_empty))
-                       charge_empty.intval = 0;
+       if (!I.intval)
+               return 0;
+
+       switch (source) {
+       case SOURCE_CHARGE:
+               full_prop = POWER_SUPPLY_PROP_CHARGE_FULL;
+               full_design_prop = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
+               empty_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
+               empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
+               cur_avg_prop = POWER_SUPPLY_PROP_CHARGE_AVG;
+               cur_now_prop = POWER_SUPPLY_PROP_CHARGE_NOW;
+               break;
+       case SOURCE_ENERGY:
+               full_prop = POWER_SUPPLY_PROP_ENERGY_FULL;
+               full_design_prop = POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
+               empty_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY;
+               empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
+               cur_avg_prop = POWER_SUPPLY_PROP_ENERGY_AVG;
+               cur_now_prop = POWER_SUPPLY_PROP_ENERGY_NOW;
+               break;
+       case SOURCE_VOLTAGE:
+               full_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX;
+               full_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN;
+               empty_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN;
+               empty_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN;
+               cur_avg_prop = POWER_SUPPLY_PROP_VOLTAGE_AVG;
+               cur_now_prop = POWER_SUPPLY_PROP_VOLTAGE_NOW;
+               break;
+       default:
+               printk(KERN_ERR "Unsupported source: %d\n", source);
+               return -1;
        }
 
-       if (MPSY_PROP(CHARGE_AVG, &charge)) {
-               /* if battery can't report average value, use momentary */
-               if (MPSY_PROP(CHARGE_NOW, &charge))
+       if (_MPSY_PROP(full_prop, &full)) {
+               /* if battery can't report this property, use design value */
+               if (_MPSY_PROP(full_design_prop, &full))
                        return -1;
        }
 
-       if (MPSY_PROP(CURRENT_AVG, &I)) {
+       if (_MPSY_PROP(empty_prop, &empty)) {
+               /* if battery can't report this property, use design value */
+               if (_MPSY_PROP(empty_design_prop, &empty))
+                       empty.intval = 0;
+       }
+
+       if (_MPSY_PROP(cur_avg_prop, &cur)) {
                /* if battery can't report average value, use momentary */
-               if (MPSY_PROP(CURRENT_NOW, &I))
+               if (_MPSY_PROP(cur_now_prop, &cur))
                        return -1;
        }
 
        if (status == POWER_SUPPLY_STATUS_CHARGING)
-               return ((charge.intval - charge_full.intval) * 60L) /
-                      I.intval;
+               return ((cur.intval - full.intval) * 60L) / I.intval;
        else
-               return -((charge.intval - charge_empty.intval) * 60L) /
-                       I.intval;
+               return -((cur.intval - empty.intval) * 60L) / I.intval;
+}
+
+static int calculate_time(int status)
+{
+       int time;
+
+       time = do_calculate_time(status, SOURCE_ENERGY);
+       if (time != -1)
+               return time;
+
+       time = do_calculate_time(status, SOURCE_CHARGE);
+       if (time != -1)
+               return time;
+
+       time = do_calculate_time(status, SOURCE_VOLTAGE);
+       if (time != -1)
+               return time;
+
+       return -1;
 }
 
-static int calculate_capacity(int using_charge)
+static int calculate_capacity(enum apm_source source)
 {
        enum power_supply_property full_prop, empty_prop;
        enum power_supply_property full_design_prop, empty_design_prop;
@@ -132,20 +217,33 @@ static int calculate_capacity(int using_charge)
        union power_supply_propval empty, full, cur;
        int ret;
 
-       if (using_charge) {
+       switch (source) {
+       case SOURCE_CHARGE:
                full_prop = POWER_SUPPLY_PROP_CHARGE_FULL;
                empty_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
                full_design_prop = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
                empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN;
                now_prop = POWER_SUPPLY_PROP_CHARGE_NOW;
                avg_prop = POWER_SUPPLY_PROP_CHARGE_AVG;
-       } else {
+               break;
+       case SOURCE_ENERGY:
                full_prop = POWER_SUPPLY_PROP_ENERGY_FULL;
                empty_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY;
                full_design_prop = POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
                empty_design_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY_DESIGN;
                now_prop = POWER_SUPPLY_PROP_ENERGY_NOW;
                avg_prop = POWER_SUPPLY_PROP_ENERGY_AVG;
+       case SOURCE_VOLTAGE:
+               full_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX;
+               empty_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN;
+               full_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN;
+               empty_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN;
+               now_prop = POWER_SUPPLY_PROP_VOLTAGE_NOW;
+               avg_prop = POWER_SUPPLY_PROP_VOLTAGE_AVG;
+               break;
+       default:
+               printk(KERN_ERR "Unsupported source: %d\n", source);
+               return -1;
        }
 
        if (_MPSY_PROP(full_prop, &full)) {
@@ -185,10 +283,10 @@ 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;
        }
 
@@ -212,10 +310,12 @@ static void apm_battery_apm_get_power_status(struct apm_power_info *info)
                info->battery_life = capacity.intval;
        } else {
                /* try calculate using energy */
-               info->battery_life = calculate_capacity(0);
+               info->battery_life = calculate_capacity(SOURCE_ENERGY);
                /* if failed try calculate using charge instead */
                if (info->battery_life == -1)
-                       info->battery_life = calculate_capacity(1);
+                       info->battery_life = calculate_capacity(SOURCE_CHARGE);
+               if (info->battery_life == -1)
+                       info->battery_life = calculate_capacity(SOURCE_VOLTAGE);
        }
 
        /* charging status */
@@ -244,13 +344,13 @@ static void apm_battery_apm_get_power_status(struct apm_power_info *info)
                        info->time = calculate_time(status.intval);
        } else {
                if (!MPSY_PROP(TIME_TO_EMPTY_AVG, &time_to_empty) ||
-                               !MPSY_PROP(TIME_TO_EMPTY_NOW, &time_to_empty))
+                             !MPSY_PROP(TIME_TO_EMPTY_NOW, &time_to_empty))
                        info->time = time_to_empty.intval / 60;
                else
                        info->time = calculate_time(status.intval);
        }
 
-       up(&power_supply_class->sem);
+       mutex_unlock(&apm_mutex);
 }
 
 static int __init apm_battery_init(void)