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
  17 #define PSY_PROP(psy, prop, val) (psy->get_property(psy, \
  18                          POWER_SUPPLY_PROP_##prop, val))
  19
  20 #define _MPSY_PROP(prop, val) (main_battery->get_property(main_battery, \
  21                                                          prop, val))
  22
  23 #define MPSY_PROP(prop, val) _MPSY_PROP(POWER_SUPPLY_PROP_##prop, val)
  24
  25 static DEFINE_MUTEX(apm_mutex);
  26 static struct power_supply *main_battery;
  27
  28 enum apm_source {
  29         SOURCE_ENERGY,
  30         SOURCE_CHARGE,
  31         SOURCE_VOLTAGE,
  32 };
  33
  34 struct find_bat_param {
  35         struct power_supply *main;
  36         struct power_supply *bat;
  37         struct power_supply *max_charge_bat;
  38         struct power_supply *max_energy_bat;
  39         union power_supply_propval full;
  40         int max_charge;
  41         int max_energy;
  42 };
  43
  44 static int __find_main_battery(struct device *dev, void *data)
  45 {
  46         struct find_bat_param *bp = (struct find_bat_param *)data;
  47
  48         bp->bat = dev_get_drvdata(dev);
  49
  50         if (bp->bat->use_for_apm) {
  51                 /* nice, we explicitly asked to report this battery. */
  52                 bp->main = bp->bat;
  53                 return 1;
  54         }
  55
  56         if (!PSY_PROP(bp->bat, CHARGE_FULL_DESIGN, &bp->full) ||
  57                         !PSY_PROP(bp->bat, CHARGE_FULL, &bp->full)) {
  58                 if (bp->full.intval > bp->max_charge) {
  59                         bp->max_charge_bat = bp->bat;
  60                         bp->max_charge = bp->full.intval;
  61                 }
  62         } else if (!PSY_PROP(bp->bat, ENERGY_FULL_DESIGN, &bp->full) ||
  63                         !PSY_PROP(bp->bat, ENERGY_FULL, &bp->full)) {
  64                 if (bp->full.intval > bp->max_energy) {
  65                         bp->max_energy_bat = bp->bat;
  66                         bp->max_energy = bp->full.intval;
  67                 }
  68         }
  69         return 0;
  70 }
  71
  72 static void find_main_battery(void)
  73 {
  74         struct find_bat_param bp;
  75         int error;
  76
  77         memset(&bp, 0, sizeof(struct find_bat_param));
  78         main_battery = NULL;
  79         bp.main = main_battery;
  80
  81         error = class_for_each_device(power_supply_class, NULL, &bp,
  82                                       __find_main_battery);
  83         if (error) {
  84                 main_battery = bp.main;
  85                 return;
  86         }
  87
  88         if ((bp.max_energy_bat && bp.max_charge_bat) &&
  89                         (bp.max_energy_bat != bp.max_charge_bat)) {
  90                 /* try guess battery with more capacity */
  91                 if (!PSY_PROP(bp.max_charge_bat, VOLTAGE_MAX_DESIGN,
  92                               &bp.full)) {
  93                         if (bp.max_energy > bp.max_charge * bp.full.intval)
  94                                 main_battery = bp.max_energy_bat;
  95                         else
  96                                 main_battery = bp.max_charge_bat;
  97                 } else if (!PSY_PROP(bp.max_energy_bat, VOLTAGE_MAX_DESIGN,
  98                                                                   &bp.full)) {
  99                         if (bp.max_charge > bp.max_energy / bp.full.intval)
 100                                 main_battery = bp.max_charge_bat;
 101                         else
 102                                 main_battery = bp.max_energy_bat;
 103                 } else {
 104                         /* give up, choice any */
 105                         main_battery = bp.max_energy_bat;
 106                 }
 107         } else if (bp.max_charge_bat) {
 108                 main_battery = bp.max_charge_bat;
 109         } else if (bp.max_energy_bat) {
 110                 main_battery = bp.max_energy_bat;
 111         } else {
 112                 /* give up, try the last if any */
 113                 main_battery = bp.bat;
 114         }
 115 }
 116
 117 static int do_calculate_time(int status, enum apm_source source)
 118 {
 119         union power_supply_propval full;
 120         union power_supply_propval empty;
 121         union power_supply_propval cur;
 122         union power_supply_propval I;
 123         enum power_supply_property full_prop;
 124         enum power_supply_property full_design_prop;
 125         enum power_supply_property empty_prop;
 126         enum power_supply_property empty_design_prop;
 127         enum power_supply_property cur_avg_prop;
 128         enum power_supply_property cur_now_prop;
 129
 130         if (MPSY_PROP(CURRENT_AVG, &I)) {
 131                 /* if battery can't report average value, use momentary */
 132                 if (MPSY_PROP(CURRENT_NOW, &I))
 133                         return -1;
 134         }
 135
 136         if (!I.intval)
 137                 return 0;
 138
 139         switch (source) {
 140         case SOURCE_CHARGE:
 141                 full_prop = POWER_SUPPLY_PROP_CHARGE_FULL;
 142                 full_design_prop = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
 143                 empty_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
 144                 empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
 145                 cur_avg_prop = POWER_SUPPLY_PROP_CHARGE_AVG;
 146                 cur_now_prop = POWER_SUPPLY_PROP_CHARGE_NOW;
 147                 break;
 148         case SOURCE_ENERGY:
 149                 full_prop = POWER_SUPPLY_PROP_ENERGY_FULL;
 150                 full_design_prop = POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
 151                 empty_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY;
 152                 empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
 153                 cur_avg_prop = POWER_SUPPLY_PROP_ENERGY_AVG;
 154                 cur_now_prop = POWER_SUPPLY_PROP_ENERGY_NOW;
 155                 break;
 156         case SOURCE_VOLTAGE:
 157                 full_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX;
 158                 full_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN;
 159                 empty_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN;
 160                 empty_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN;
 161                 cur_avg_prop = POWER_SUPPLY_PROP_VOLTAGE_AVG;
 162                 cur_now_prop = POWER_SUPPLY_PROP_VOLTAGE_NOW;
 163                 break;
 164         default:
 165                 printk(KERN_ERR "Unsupported source: %d\n", source);
 166                 return -1;
 167         }
 168
 169         if (_MPSY_PROP(full_prop, &full)) {
 170                 /* if battery can't report this property, use design value */
 171                 if (_MPSY_PROP(full_design_prop, &full))
 172                         return -1;
 173         }
 174
 175         if (_MPSY_PROP(empty_prop, &empty)) {
 176                 /* if battery can't report this property, use design value */
 177                 if (_MPSY_PROP(empty_design_prop, &empty))
 178                         empty.intval = 0;
 179         }
 180
 181         if (_MPSY_PROP(cur_avg_prop, &cur)) {
 182                 /* if battery can't report average value, use momentary */
 183                 if (_MPSY_PROP(cur_now_prop, &cur))
 184                         return -1;
 185         }
 186
 187         if (status == POWER_SUPPLY_STATUS_CHARGING)
 188                 return ((cur.intval - full.intval) * 60L) / I.intval;
 189         else
 190                 return -((cur.intval - empty.intval) * 60L) / I.intval;
 191 }
 192
 193 static int calculate_time(int status)
 194 {
 195         int time;
 196
 197         time = do_calculate_time(status, SOURCE_ENERGY);
 198         if (time != -1)
 199                 return time;
 200
 201         time = do_calculate_time(status, SOURCE_CHARGE);
 202         if (time != -1)
 203                 return time;
 204
 205         time = do_calculate_time(status, SOURCE_VOLTAGE);
 206         if (time != -1)
 207                 return time;
 208
 209         return -1;
 210 }
 211
 212 static int calculate_capacity(enum apm_source source)
 213 {
 214         enum power_supply_property full_prop, empty_prop;
 215         enum power_supply_property full_design_prop, empty_design_prop;
 216         enum power_supply_property now_prop, avg_prop;
 217         union power_supply_propval empty, full, cur;
 218         int ret;
 219
 220         switch (source) {
 221         case SOURCE_CHARGE:
 222                 full_prop = POWER_SUPPLY_PROP_CHARGE_FULL;
 223                 empty_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
 224                 full_design_prop = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
 225                 empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN;
 226                 now_prop = POWER_SUPPLY_PROP_CHARGE_NOW;
 227                 avg_prop = POWER_SUPPLY_PROP_CHARGE_AVG;
 228                 break;
 229         case SOURCE_ENERGY:
 230                 full_prop = POWER_SUPPLY_PROP_ENERGY_FULL;
 231                 empty_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY;
 232                 full_design_prop = POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
 233                 empty_design_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY_DESIGN;
 234                 now_prop = POWER_SUPPLY_PROP_ENERGY_NOW;
 235                 avg_prop = POWER_SUPPLY_PROP_ENERGY_AVG;
 236                 break;
 237         case SOURCE_VOLTAGE:
 238                 full_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX;
 239                 empty_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN;
 240                 full_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN;
 241                 empty_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN;
 242                 now_prop = POWER_SUPPLY_PROP_VOLTAGE_NOW;
 243                 avg_prop = POWER_SUPPLY_PROP_VOLTAGE_AVG;
 244                 break;
 245         default:
 246                 printk(KERN_ERR "Unsupported source: %d\n", source);
 247                 return -1;
 248         }
 249
 250         if (_MPSY_PROP(full_prop, &full)) {
 251                 /* if battery can't report this property, use design value */
 252                 if (_MPSY_PROP(full_design_prop, &full))
 253                         return -1;
 254         }
 255
 256         if (_MPSY_PROP(avg_prop, &cur)) {
 257                 /* if battery can't report average value, use momentary */
 258                 if (_MPSY_PROP(now_prop, &cur))
 259                         return -1;
 260         }
 261
 262         if (_MPSY_PROP(empty_prop, &empty)) {
 263                 /* if battery can't report this property, use design value */
 264                 if (_MPSY_PROP(empty_design_prop, &empty))
 265                         empty.intval = 0;
 266         }
 267
 268         if (full.intval - empty.intval)
 269                 ret =  ((cur.intval - empty.intval) * 100L) /
 270                        (full.intval - empty.intval);
 271         else
 272                 return -1;
 273
 274         if (ret > 100)
 275                 return 100;
 276         else if (ret < 0)
 277                 return 0;
 278
 279         return ret;
 280 }
 281
 282 static void apm_battery_apm_get_power_status(struct apm_power_info *info)
 283 {
 284         union power_supply_propval status;
 285         union power_supply_propval capacity, time_to_full, time_to_empty;
 286
 287         mutex_lock(&apm_mutex);
 288         find_main_battery();
 289         if (!main_battery) {
 290                 mutex_unlock(&apm_mutex);
 291                 return;
 292         }
 293
 294         /* status */
 295
 296         if (MPSY_PROP(STATUS, &status))
 297                 status.intval = POWER_SUPPLY_STATUS_UNKNOWN;
 298
 299         /* ac line status */
 300
 301         if ((status.intval == POWER_SUPPLY_STATUS_CHARGING) ||
 302             (status.intval == POWER_SUPPLY_STATUS_NOT_CHARGING) ||
 303             (status.intval == POWER_SUPPLY_STATUS_FULL))
 304                 info->ac_line_status = APM_AC_ONLINE;
 305         else
 306                 info->ac_line_status = APM_AC_OFFLINE;
 307
 308         /* battery life (i.e. capacity, in percents) */
 309
 310         if (MPSY_PROP(CAPACITY, &capacity) == 0) {
 311                 info->battery_life = capacity.intval;
 312         } else {
 313                 /* try calculate using energy */
 314                 info->battery_life = calculate_capacity(SOURCE_ENERGY);
 315                 /* if failed try calculate using charge instead */
 316                 if (info->battery_life == -1)
 317                         info->battery_life = calculate_capacity(SOURCE_CHARGE);
 318                 if (info->battery_life == -1)
 319                         info->battery_life = calculate_capacity(SOURCE_VOLTAGE);
 320         }
 321
 322         /* charging status */
 323
 324         if (status.intval == POWER_SUPPLY_STATUS_CHARGING) {
 325                 info->battery_status = APM_BATTERY_STATUS_CHARGING;
 326         } else {
 327                 if (info->battery_life > 50)
 328                         info->battery_status = APM_BATTERY_STATUS_HIGH;
 329                 else if (info->battery_life > 5)
 330                         info->battery_status = APM_BATTERY_STATUS_LOW;
 331                 else
 332                         info->battery_status = APM_BATTERY_STATUS_CRITICAL;
 333         }
 334         info->battery_flag = info->battery_status;
 335
 336         /* time */
 337
 338         info->units = APM_UNITS_MINS;
 339
 340         if (status.intval == POWER_SUPPLY_STATUS_CHARGING) {
 341                 if (!MPSY_PROP(TIME_TO_FULL_AVG, &time_to_full) ||
 342                                 !MPSY_PROP(TIME_TO_FULL_NOW, &time_to_full))
 343                         info->time = time_to_full.intval / 60;
 344                 else
 345                         info->time = calculate_time(status.intval);
 346         } else {
 347                 if (!MPSY_PROP(TIME_TO_EMPTY_AVG, &time_to_empty) ||
 348                               !MPSY_PROP(TIME_TO_EMPTY_NOW, &time_to_empty))
 349                         info->time = time_to_empty.intval / 60;
 350                 else
 351                         info->time = calculate_time(status.intval);
 352         }
 353
 354         mutex_unlock(&apm_mutex);
 355 }
 356
 357 static int __init apm_battery_init(void)
 358 {
 359         printk(KERN_INFO "APM Battery Driver\n");
 360
 361         apm_get_power_status = apm_battery_apm_get_power_status;
 362         return 0;
 363 }
 364
 365 static void __exit apm_battery_exit(void)
 366 {
 367         apm_get_power_status = NULL;
 368 }
 369
 370 module_init(apm_battery_init);
 371 module_exit(apm_battery_exit);
 372
 373 MODULE_AUTHOR("Eugeny Boger <eugenyboger@dgap.mipt.ru>");
 374 MODULE_DESCRIPTION("APM emulation driver for battery monitoring class");
 375 MODULE_LICENSE("GPL");