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 39a90a6f0f803110964260d02a167c1256a6394e..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;
 
+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;
+       int max_energy;
+};
+
+static int __find_main_battery(struct device *dev, void *data)
+{
+       struct find_bat_param *bp = (struct find_bat_param *)data;
+
+       bp->bat = dev_get_drvdata(dev);
+
+       if (bp->bat->use_for_apm) {
+               /* nice, we explicitly asked to report this battery. */
+               bp->main = bp->bat;
+               return 1;
+       }
+
+       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 device *dev;
-       struct power_supply *bat, *batm;
-       union power_supply_propval full;
-       int max_charge = 0;
+       struct find_bat_param bp;
+       int error;
 
+       memset(&bp, 0, sizeof(struct find_bat_param));
        main_battery = NULL;
-       batm = NULL;
-       list_for_each_entry(dev, &power_supply_class->devices, node) {
-               bat = dev_get_drvdata(dev);
-               /* If none of battery devices cantains 'use_for_apm' flag,
-                  choice one with maximum design charge */
-               if (!PSY_PROP(bat, CHARGE_FULL_DESIGN, &full)) {
-                       if (full.intval > max_charge) {
-                               batm = bat;
-                               max_charge = full.intval;
-                       }
-               }
+       bp.main = main_battery;
+
+       error = class_for_each_device(power_supply_class, &bp,
+                                     __find_main_battery);
+       if (error) {
+               main_battery = bp.main;
+               return;
+       }
 
-               if (bat->use_for_apm)
-                       main_battery = 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(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 = 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 = bp.max_energy_bat;
+               } else {
+                       /* give up, choice any */
+                       main_battery = bp.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 = bp.bat;
        }
-       if (!main_battery)
-               main_battery = batm;
 }
 
-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_capacity(int using_charge)
+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(enum apm_source source)
 {
        enum power_supply_property full_prop, empty_prop;
        enum power_supply_property full_design_prop, empty_design_prop;
@@ -95,20 +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)) {
@@ -148,10 +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;
        }
 
@@ -175,10 +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 */
@@ -200,22 +337,20 @@ static void apm_battery_apm_get_power_status(struct apm_power_info *info)
        info->units = APM_UNITS_MINS;
 
        if (status.intval == POWER_SUPPLY_STATUS_CHARGING) {
-               if (MPSY_PROP(TIME_TO_FULL_AVG, &time_to_full)) {
-                       if (MPSY_PROP(TIME_TO_FULL_NOW, &time_to_full))
-                               info->time = calculate_time(status.intval);
-                       else
-                               info->time = time_to_full.intval / 60;
-               }
+               if (!MPSY_PROP(TIME_TO_FULL_AVG, &time_to_full) ||
+                               !MPSY_PROP(TIME_TO_FULL_NOW, &time_to_full))
+                       info->time = time_to_full.intval / 60;
+               else
+                       info->time = calculate_time(status.intval);
        } else {
-               if (MPSY_PROP(TIME_TO_EMPTY_AVG, &time_to_empty)) {
-                       if (MPSY_PROP(TIME_TO_EMPTY_NOW, &time_to_empty))
-                               info->time = calculate_time(status.intval);
-                       else
-                               info->time = time_to_empty.intval / 60;
-               }
+               if (!MPSY_PROP(TIME_TO_EMPTY_AVG, &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)