drivers/power/apm_power.c

   1 /*
   2  * Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
   3  * Copyright © 2007 Eugeny Boger <eugenyboger@dgap.mipt.ru>
   4  *
   5  * Author: Eugeny Boger <eugenyboger@dgap.mipt.ru>
   6  *
   7  * Use consistent with the GNU GPL is permitted,
   8  * provided that this copyright notice is
   9  * preserved in its entirety in all copies and derived works.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/power_supply.h>
  14 #include <linux/apm-emulation.h>
  15
  16 #define PSY_PROP(psy, prop, val) psy->get_property(psy, \
  17                          POWER_SUPPLY_PROP_##prop, val)
  18
  19 #define _MPSY_PROP(prop, val) main_battery->get_property(main_battery, \
  20                                                          prop, val)
  21
  22 #define MPSY_PROP(prop, val) _MPSY_PROP(POWER_SUPPLY_PROP_##prop, val)
  23
  24 static struct power_supply *main_battery;
  25
  26 static void find_main_battery(void)
  27 {
  28         struct device *dev;
  29         struct power_supply *bat = NULL;
  30         struct power_supply *max_charge_bat = NULL;
  31         struct power_supply *max_energy_bat = NULL;
  32         union power_supply_propval full;
  33         int max_charge = 0;
  34         int max_energy = 0;
  35
  36         main_battery = NULL;
  37
  38         list_for_each_entry(dev, &power_supply_class->devices, node) {
  39                 bat = dev_get_drvdata(dev);
  40
  41                 if (bat->use_for_apm) {
  42                         /* nice, we explicitly asked to report this battery. */
  43                         main_battery = bat;
  44                         return;
  45                 }
  46
  47                 if (!PSY_PROP(bat, CHARGE_FULL_DESIGN, &full) ||
  48                                 !PSY_PROP(bat, CHARGE_FULL, &full)) {
  49                         if (full.intval > max_charge) {
  50                                 max_charge_bat = bat;
  51                                 max_charge = full.intval;
  52                         }
  53                 } else if (!PSY_PROP(bat, ENERGY_FULL_DESIGN, &full) ||
  54                                 !PSY_PROP(bat, ENERGY_FULL, &full)) {
  55                         if (full.intval > max_energy) {
  56                                 max_energy_bat = bat;
  57                                 max_energy = full.intval;
  58                         }
  59                 }
  60         }
  61
  62         if ((max_energy_bat && max_charge_bat) &&
  63                         (max_energy_bat != max_charge_bat)) {
  64                 /* try guess battery with more capacity */
  65                 if (!PSY_PROP(max_charge_bat, VOLTAGE_MAX_DESIGN, &full)) {
  66                         if (max_energy > max_charge * full.intval)
  67                                 main_battery = max_energy_bat;
  68                         else
  69                                 main_battery = max_charge_bat;
  70                 } else if (!PSY_PROP(max_energy_bat, VOLTAGE_MAX_DESIGN,
  71                                                                   &full)) {
  72                         if (max_charge > max_energy / full.intval)
  73                                 main_battery = max_charge_bat;
  74                         else
  75                                 main_battery = max_energy_bat;
  76                 } else {
  77                         /* give up, choice any */
  78                         main_battery = max_energy_bat;
  79                 }
  80         } else if (max_charge_bat) {
  81                 main_battery = max_charge_bat;
  82         } else if (max_energy_bat) {
  83                 main_battery = max_energy_bat;
  84         } else {
  85                 /* give up, try the last if any */
  86                 main_battery = bat;
  87         }
  88 }
  89
  90 static int calculate_time(int status, int using_charge)
  91 {
  92         union power_supply_propval full;
  93         union power_supply_propval empty;
  94         union power_supply_propval cur;
  95         union power_supply_propval I;
  96         enum power_supply_property full_prop;
  97         enum power_supply_property full_design_prop;
  98         enum power_supply_property empty_prop;
  99         enum power_supply_property empty_design_prop;
 100         enum power_supply_property cur_avg_prop;
 101         enum power_supply_property cur_now_prop;
 102
 103         if (MPSY_PROP(CURRENT_AVG, &I)) {
 104                 /* if battery can't report average value, use momentary */
 105                 if (MPSY_PROP(CURRENT_NOW, &I))
 106                         return -1;
 107         }
 108
 109         if (using_charge) {
 110                 full_prop = POWER_SUPPLY_PROP_CHARGE_FULL;
 111                 full_design_prop = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
 112                 empty_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
 113                 empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
 114                 cur_avg_prop = POWER_SUPPLY_PROP_CHARGE_AVG;
 115                 cur_now_prop = POWER_SUPPLY_PROP_CHARGE_NOW;
 116         } else {
 117                 full_prop = POWER_SUPPLY_PROP_ENERGY_FULL;
 118                 full_design_prop = POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
 119                 empty_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY;
 120                 empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
 121                 cur_avg_prop = POWER_SUPPLY_PROP_ENERGY_AVG;
 122                 cur_now_prop = POWER_SUPPLY_PROP_ENERGY_NOW;
 123         }
 124
 125         if (_MPSY_PROP(full_prop, &full)) {
 126                 /* if battery can't report this property, use design value */
 127                 if (_MPSY_PROP(full_design_prop, &full))
 128                         return -1;
 129         }
 130
 131         if (_MPSY_PROP(empty_prop, &empty)) {
 132                 /* if battery can't report this property, use design value */
 133                 if (_MPSY_PROP(empty_design_prop, &empty))
 134                         empty.intval = 0;
 135         }
 136
 137         if (_MPSY_PROP(cur_avg_prop, &cur)) {
 138                 /* if battery can't report average value, use momentary */
 139                 if (_MPSY_PROP(cur_now_prop, &cur))
 140                         return -1;
 141         }
 142
 143         if (status == POWER_SUPPLY_STATUS_CHARGING)
 144                 return ((cur.intval - full.intval) * 60L) / I.intval;
 145         else
 146                 return -((cur.intval - empty.intval) * 60L) / I.intval;
 147 }
 148
 149 static int calculate_capacity(int using_charge)
 150 {
 151         enum power_supply_property full_prop, empty_prop;
 152         enum power_supply_property full_design_prop, empty_design_prop;
 153         enum power_supply_property now_prop, avg_prop;
 154         union power_supply_propval empty, full, cur;
 155         int ret;
 156
 157         if (using_charge) {
 158                 full_prop = POWER_SUPPLY_PROP_CHARGE_FULL;
 159                 empty_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
 160                 full_design_prop = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
 161                 empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN;
 162                 now_prop = POWER_SUPPLY_PROP_CHARGE_NOW;
 163                 avg_prop = POWER_SUPPLY_PROP_CHARGE_AVG;
 164         } else {
 165                 full_prop = POWER_SUPPLY_PROP_ENERGY_FULL;
 166                 empty_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY;
 167                 full_design_prop = POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
 168                 empty_design_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY_DESIGN;
 169                 now_prop = POWER_SUPPLY_PROP_ENERGY_NOW;
 170                 avg_prop = POWER_SUPPLY_PROP_ENERGY_AVG;
 171         }
 172
 173         if (_MPSY_PROP(full_prop, &full)) {
 174                 /* if battery can't report this property, use design value */
 175                 if (_MPSY_PROP(full_design_prop, &full))
 176                         return -1;
 177         }
 178
 179         if (_MPSY_PROP(avg_prop, &cur)) {
 180                 /* if battery can't report average value, use momentary */
 181                 if (_MPSY_PROP(now_prop, &cur))
 182                         return -1;
 183         }
 184
 185         if (_MPSY_PROP(empty_prop, &empty)) {
 186                 /* if battery can't report this property, use design value */
 187                 if (_MPSY_PROP(empty_design_prop, &empty))
 188                         empty.intval = 0;
 189         }
 190
 191         if (full.intval - empty.intval)
 192                 ret =  ((cur.intval - empty.intval) * 100L) /
 193                        (full.intval - empty.intval);
 194         else
 195                 return -1;
 196
 197         if (ret > 100)
 198                 return 100;
 199         else if (ret < 0)
 200                 return 0;
 201
 202         return ret;
 203 }
 204
 205 static void apm_battery_apm_get_power_status(struct apm_power_info *info)
 206 {
 207         union power_supply_propval status;
 208         union power_supply_propval capacity, time_to_full, time_to_empty;
 209
 210         down(&power_supply_class->sem);
 211         find_main_battery();
 212         if (!main_battery) {
 213                 up(&power_supply_class->sem);
 214                 return;
 215         }
 216
 217         /* status */
 218
 219         if (MPSY_PROP(STATUS, &status))
 220                 status.intval = POWER_SUPPLY_STATUS_UNKNOWN;
 221
 222         /* ac line status */
 223
 224         if ((status.intval == POWER_SUPPLY_STATUS_CHARGING) ||
 225             (status.intval == POWER_SUPPLY_STATUS_NOT_CHARGING) ||
 226             (status.intval == POWER_SUPPLY_STATUS_FULL))
 227                 info->ac_line_status = APM_AC_ONLINE;
 228         else
 229                 info->ac_line_status = APM_AC_OFFLINE;
 230
 231         /* battery life (i.e. capacity, in percents) */
 232
 233         if (MPSY_PROP(CAPACITY, &capacity) == 0) {
 234                 info->battery_life = capacity.intval;
 235         } else {
 236                 /* try calculate using energy */
 237                 info->battery_life = calculate_capacity(0);
 238                 /* if failed try calculate using charge instead */
 239                 if (info->battery_life == -1)
 240                         info->battery_life = calculate_capacity(1);
 241         }
 242
 243         /* charging status */
 244
 245         if (status.intval == POWER_SUPPLY_STATUS_CHARGING) {
 246                 info->battery_status = APM_BATTERY_STATUS_CHARGING;
 247         } else {
 248                 if (info->battery_life > 50)
 249                         info->battery_status = APM_BATTERY_STATUS_HIGH;
 250                 else if (info->battery_life > 5)
 251                         info->battery_status = APM_BATTERY_STATUS_LOW;
 252                 else
 253                         info->battery_status = APM_BATTERY_STATUS_CRITICAL;
 254         }
 255         info->battery_flag = info->battery_status;
 256
 257         /* time */
 258
 259         info->units = APM_UNITS_MINS;
 260
 261         if (status.intval == POWER_SUPPLY_STATUS_CHARGING) {
 262                 if (!MPSY_PROP(TIME_TO_FULL_AVG, &time_to_full) ||
 263                                 !MPSY_PROP(TIME_TO_FULL_NOW, &time_to_full)) {
 264                         info->time = time_to_full.intval / 60;
 265                 } else {
 266                         info->time = calculate_time(status.intval, 0);
 267                         if (info->time == -1)
 268                                 info->time = calculate_time(status.intval, 1);
 269                 }
 270         } else {
 271                 if (!MPSY_PROP(TIME_TO_EMPTY_AVG, &time_to_empty) ||
 272                               !MPSY_PROP(TIME_TO_EMPTY_NOW, &time_to_empty)) {
 273                         info->time = time_to_empty.intval / 60;
 274                 } else {
 275                         info->time = calculate_time(status.intval, 0);
 276                         if (info->time == -1)
 277                                 info->time = calculate_time(status.intval, 1);
 278                 }
 279         }
 280
 281         up(&power_supply_class->sem);
 282 }
 283
 284 static int __init apm_battery_init(void)
 285 {
 286         printk(KERN_INFO "APM Battery Driver\n");
 287
 288         apm_get_power_status = apm_battery_apm_get_power_status;
 289         return 0;
 290 }
 291
 292 static void __exit apm_battery_exit(void)
 293 {
 294         apm_get_power_status = NULL;
 295 }
 296
 297 module_init(apm_battery_init);
 298 module_exit(apm_battery_exit);
 299
 300 MODULE_AUTHOR("Eugeny Boger <eugenyboger@dgap.mipt.ru>");
 301 MODULE_DESCRIPTION("APM emulation driver for battery monitoring class");
 302 MODULE_LICENSE("GPL");