drivers/power/supply/s3c_adc_battery.c

   1 /*
   2  *      iPAQ h1930/h1940/rx1950 battery controller driver
   3  *      Copyright (c) Vasily Khoruzhick
   4  *      Based on h1940_battery.c by Arnaud Patard
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License.  See the file COPYING in the main directory of this archive for
   8  * more details.
   9  *
  10  */
  11
  12 #include <linux/interrupt.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/power_supply.h>
  15 #include <linux/leds.h>
  16 #include <linux/gpio/consumer.h>
  17 #include <linux/err.h>
  18 #include <linux/timer.h>
  19 #include <linux/jiffies.h>
  20 #include <linux/s3c_adc_battery.h>
  21 #include <linux/errno.h>
  22 #include <linux/init.h>
  23 #include <linux/module.h>
  24
  25 #include <linux/soc/samsung/s3c-adc.h>
  26
  27 #define BAT_POLL_INTERVAL               10000 /* ms */
  28 #define JITTER_DELAY                    500 /* ms */
  29
  30 struct s3c_adc_bat {
  31         struct power_supply             *psy;
  32         struct s3c_adc_client           *client;
  33         struct s3c_adc_bat_pdata        *pdata;
  34         struct gpio_desc                *charge_finished;
  35         int                             volt_value;
  36         int                             cur_value;
  37         unsigned int                    timestamp;
  38         int                             level;
  39         int                             status;
  40         int                             cable_plugged:1;
  41 };
  42
  43 static struct delayed_work bat_work;
  44
  45 static void s3c_adc_bat_ext_power_changed(struct power_supply *psy)
  46 {
  47         schedule_delayed_work(&bat_work,
  48                 msecs_to_jiffies(JITTER_DELAY));
  49 }
  50
  51 static int gather_samples(struct s3c_adc_client *client, int num, int channel)
  52 {
  53         int value, i;
  54
  55         /* default to 1 if nothing is set */
  56         if (num < 1)
  57                 num = 1;
  58
  59         value = 0;
  60         for (i = 0; i < num; i++)
  61                 value += s3c_adc_read(client, channel);
  62         value /= num;
  63
  64         return value;
  65 }
  66
  67 static enum power_supply_property s3c_adc_backup_bat_props[] = {
  68         POWER_SUPPLY_PROP_VOLTAGE_NOW,
  69         POWER_SUPPLY_PROP_VOLTAGE_MIN,
  70         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
  71 };
  72
  73 static int s3c_adc_backup_bat_get_property(struct power_supply *psy,
  74                                 enum power_supply_property psp,
  75                                 union power_supply_propval *val)
  76 {
  77         struct s3c_adc_bat *bat = power_supply_get_drvdata(psy);
  78
  79         if (!bat) {
  80                 dev_err(&psy->dev, "%s: no battery infos ?!\n", __func__);
  81                 return -EINVAL;
  82         }
  83
  84         if (bat->volt_value < 0 ||
  85                 jiffies_to_msecs(jiffies - bat->timestamp) >
  86                         BAT_POLL_INTERVAL) {
  87                 bat->volt_value = gather_samples(bat->client,
  88                         bat->pdata->backup_volt_samples,
  89                         bat->pdata->backup_volt_channel);
  90                 bat->volt_value *= bat->pdata->backup_volt_mult;
  91                 bat->timestamp = jiffies;
  92         }
  93
  94         switch (psp) {
  95         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
  96                 val->intval = bat->volt_value;
  97                 return 0;
  98         case POWER_SUPPLY_PROP_VOLTAGE_MIN:
  99                 val->intval = bat->pdata->backup_volt_min;
 100                 return 0;
 101         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 102                 val->intval = bat->pdata->backup_volt_max;
 103                 return 0;
 104         default:
 105                 return -EINVAL;
 106         }
 107 }
 108
 109 static const struct power_supply_desc backup_bat_desc = {
 110         .name           = "backup-battery",
 111         .type           = POWER_SUPPLY_TYPE_BATTERY,
 112         .properties     = s3c_adc_backup_bat_props,
 113         .num_properties = ARRAY_SIZE(s3c_adc_backup_bat_props),
 114         .get_property   = s3c_adc_backup_bat_get_property,
 115         .use_for_apm    = 1,
 116 };
 117
 118 static struct s3c_adc_bat backup_bat;
 119
 120 static enum power_supply_property s3c_adc_main_bat_props[] = {
 121         POWER_SUPPLY_PROP_STATUS,
 122         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 123         POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
 124         POWER_SUPPLY_PROP_CHARGE_NOW,
 125         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 126         POWER_SUPPLY_PROP_CURRENT_NOW,
 127 };
 128
 129 static int calc_full_volt(int volt_val, int cur_val, int impedance)
 130 {
 131         return volt_val + cur_val * impedance / 1000;
 132 }
 133
 134 static int charge_finished(struct s3c_adc_bat *bat)
 135 {
 136         return gpiod_get_value(bat->charge_finished);
 137 }
 138
 139 static int s3c_adc_bat_get_property(struct power_supply *psy,
 140                                     enum power_supply_property psp,
 141                                     union power_supply_propval *val)
 142 {
 143         struct s3c_adc_bat *bat = power_supply_get_drvdata(psy);
 144
 145         int new_level;
 146         int full_volt;
 147         const struct s3c_adc_bat_thresh *lut;
 148         unsigned int lut_size;
 149
 150         if (!bat) {
 151                 dev_err(&psy->dev, "no battery infos ?!\n");
 152                 return -EINVAL;
 153         }
 154
 155         lut = bat->pdata->lut_noac;
 156         lut_size = bat->pdata->lut_noac_cnt;
 157
 158         if (bat->volt_value < 0 || bat->cur_value < 0 ||
 159                 jiffies_to_msecs(jiffies - bat->timestamp) >
 160                         BAT_POLL_INTERVAL) {
 161                 bat->volt_value = gather_samples(bat->client,
 162                         bat->pdata->volt_samples,
 163                         bat->pdata->volt_channel) * bat->pdata->volt_mult;
 164                 bat->cur_value = gather_samples(bat->client,
 165                         bat->pdata->current_samples,
 166                         bat->pdata->current_channel) * bat->pdata->current_mult;
 167                 bat->timestamp = jiffies;
 168         }
 169
 170         if (bat->cable_plugged &&
 171                 (!bat->charge_finished ||
 172                 !charge_finished(bat))) {
 173                 lut = bat->pdata->lut_acin;
 174                 lut_size = bat->pdata->lut_acin_cnt;
 175         }
 176
 177         new_level = 100000;
 178         full_volt = calc_full_volt((bat->volt_value / 1000),
 179                 (bat->cur_value / 1000), bat->pdata->internal_impedance);
 180
 181         if (full_volt < calc_full_volt(lut->volt, lut->cur,
 182                 bat->pdata->internal_impedance)) {
 183                 lut_size--;
 184                 while (lut_size--) {
 185                         int lut_volt1;
 186                         int lut_volt2;
 187
 188                         lut_volt1 = calc_full_volt(lut[0].volt, lut[0].cur,
 189                                 bat->pdata->internal_impedance);
 190                         lut_volt2 = calc_full_volt(lut[1].volt, lut[1].cur,
 191                                 bat->pdata->internal_impedance);
 192                         if (full_volt < lut_volt1 && full_volt >= lut_volt2) {
 193                                 new_level = (lut[1].level +
 194                                         (lut[0].level - lut[1].level) *
 195                                         (full_volt - lut_volt2) /
 196                                         (lut_volt1 - lut_volt2)) * 1000;
 197                                 break;
 198                         }
 199                         new_level = lut[1].level * 1000;
 200                         lut++;
 201                 }
 202         }
 203
 204         bat->level = new_level;
 205
 206         switch (psp) {
 207         case POWER_SUPPLY_PROP_STATUS:
 208                 if (!bat->charge_finished)
 209                         val->intval = bat->level == 100000 ?
 210                                 POWER_SUPPLY_STATUS_FULL : bat->status;
 211                 else
 212                         val->intval = bat->status;
 213                 return 0;
 214         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 215                 val->intval = 100000;
 216                 return 0;
 217         case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
 218                 val->intval = 0;
 219                 return 0;
 220         case POWER_SUPPLY_PROP_CHARGE_NOW:
 221                 val->intval = bat->level;
 222                 return 0;
 223         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 224                 val->intval = bat->volt_value;
 225                 return 0;
 226         case POWER_SUPPLY_PROP_CURRENT_NOW:
 227                 val->intval = bat->cur_value;
 228                 return 0;
 229         default:
 230                 return -EINVAL;
 231         }
 232 }
 233
 234 static const struct power_supply_desc main_bat_desc = {
 235         .name                   = "main-battery",
 236         .type                   = POWER_SUPPLY_TYPE_BATTERY,
 237         .properties             = s3c_adc_main_bat_props,
 238         .num_properties         = ARRAY_SIZE(s3c_adc_main_bat_props),
 239         .get_property           = s3c_adc_bat_get_property,
 240         .external_power_changed = s3c_adc_bat_ext_power_changed,
 241         .use_for_apm            = 1,
 242 };
 243
 244 static struct s3c_adc_bat main_bat;
 245
 246 static void s3c_adc_bat_work(struct work_struct *work)
 247 {
 248         struct s3c_adc_bat *bat = &main_bat;
 249         int is_charged;
 250         int is_plugged;
 251         static int was_plugged;
 252
 253         is_plugged = power_supply_am_i_supplied(bat->psy);
 254         bat->cable_plugged = is_plugged;
 255         if (is_plugged != was_plugged) {
 256                 was_plugged = is_plugged;
 257                 if (is_plugged) {
 258                         if (bat->pdata->enable_charger)
 259                                 bat->pdata->enable_charger();
 260                         bat->status = POWER_SUPPLY_STATUS_CHARGING;
 261                 } else {
 262                         if (bat->pdata->disable_charger)
 263                                 bat->pdata->disable_charger();
 264                         bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
 265                 }
 266         } else {
 267                 if (bat->charge_finished && is_plugged) {
 268                         is_charged = charge_finished(&main_bat);
 269                         if (is_charged) {
 270                                 if (bat->pdata->disable_charger)
 271                                         bat->pdata->disable_charger();
 272                                 bat->status = POWER_SUPPLY_STATUS_FULL;
 273                         } else {
 274                                 if (bat->pdata->enable_charger)
 275                                         bat->pdata->enable_charger();
 276                                 bat->status = POWER_SUPPLY_STATUS_CHARGING;
 277                         }
 278                 }
 279         }
 280
 281         power_supply_changed(bat->psy);
 282 }
 283
 284 static irqreturn_t s3c_adc_bat_charged(int irq, void *dev_id)
 285 {
 286         schedule_delayed_work(&bat_work,
 287                 msecs_to_jiffies(JITTER_DELAY));
 288         return IRQ_HANDLED;
 289 }
 290
 291 static int s3c_adc_bat_probe(struct platform_device *pdev)
 292 {
 293         struct s3c_adc_client   *client;
 294         struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
 295         struct power_supply_config psy_cfg = {};
 296         struct gpio_desc *gpiod;
 297         int ret;
 298
 299         client = s3c_adc_register(pdev, NULL, NULL, 0);
 300         if (IS_ERR(client)) {
 301                 dev_err(&pdev->dev, "cannot register adc\n");
 302                 return PTR_ERR(client);
 303         }
 304
 305         platform_set_drvdata(pdev, client);
 306
 307         gpiod = devm_gpiod_get_optional(&pdev->dev, "charge-status", GPIOD_IN);
 308         if (IS_ERR(gpiod)) {
 309                 /* Could be probe deferral etc */
 310                 ret = PTR_ERR(gpiod);
 311                 dev_err(&pdev->dev, "no GPIO %d\n", ret);
 312                 return ret;
 313         }
 314
 315         main_bat.client = client;
 316         main_bat.pdata = pdata;
 317         main_bat.charge_finished = gpiod;
 318         main_bat.volt_value = -1;
 319         main_bat.cur_value = -1;
 320         main_bat.cable_plugged = 0;
 321         main_bat.status = POWER_SUPPLY_STATUS_DISCHARGING;
 322         psy_cfg.drv_data = &main_bat;
 323
 324         main_bat.psy = power_supply_register(&pdev->dev, &main_bat_desc, &psy_cfg);
 325         if (IS_ERR(main_bat.psy)) {
 326                 ret = PTR_ERR(main_bat.psy);
 327                 goto err_reg_main;
 328         }
 329         if (pdata->backup_volt_mult) {
 330                 const struct power_supply_config backup_psy_cfg
 331                                                 = { .drv_data = &backup_bat, };
 332
 333                 backup_bat.client = client;
 334                 backup_bat.pdata = pdev->dev.platform_data;
 335                 backup_bat.charge_finished = gpiod;
 336                 backup_bat.volt_value = -1;
 337                 backup_bat.psy = power_supply_register(&pdev->dev,
 338                                                        &backup_bat_desc,
 339                                                        &backup_psy_cfg);
 340                 if (IS_ERR(backup_bat.psy)) {
 341                         ret = PTR_ERR(backup_bat.psy);
 342                         goto err_reg_backup;
 343                 }
 344         }
 345
 346         INIT_DELAYED_WORK(&bat_work, s3c_adc_bat_work);
 347
 348         if (gpiod) {
 349                 ret = request_irq(gpiod_to_irq(gpiod),
 350                                 s3c_adc_bat_charged,
 351                                 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 352                                 "battery charged", NULL);
 353                 if (ret)
 354                         goto err_irq;
 355         }
 356
 357         if (pdata->init) {
 358                 ret = pdata->init();
 359                 if (ret)
 360                         goto err_platform;
 361         }
 362
 363         dev_info(&pdev->dev, "successfully loaded\n");
 364         device_init_wakeup(&pdev->dev, 1);
 365
 366         /* Schedule timer to check current status */
 367         schedule_delayed_work(&bat_work,
 368                 msecs_to_jiffies(JITTER_DELAY));
 369
 370         return 0;
 371
 372 err_platform:
 373         if (gpiod)
 374                 free_irq(gpiod_to_irq(gpiod), NULL);
 375 err_irq:
 376         if (pdata->backup_volt_mult)
 377                 power_supply_unregister(backup_bat.psy);
 378 err_reg_backup:
 379         power_supply_unregister(main_bat.psy);
 380 err_reg_main:
 381         return ret;
 382 }
 383
 384 static int s3c_adc_bat_remove(struct platform_device *pdev)
 385 {
 386         struct s3c_adc_client *client = platform_get_drvdata(pdev);
 387         struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
 388
 389         power_supply_unregister(main_bat.psy);
 390         if (pdata->backup_volt_mult)
 391                 power_supply_unregister(backup_bat.psy);
 392
 393         s3c_adc_release(client);
 394
 395         if (main_bat.charge_finished)
 396                 free_irq(gpiod_to_irq(main_bat.charge_finished), NULL);
 397
 398         cancel_delayed_work(&bat_work);
 399
 400         if (pdata->exit)
 401                 pdata->exit();
 402
 403         return 0;
 404 }
 405
 406 #ifdef CONFIG_PM
 407 static int s3c_adc_bat_suspend(struct platform_device *pdev,
 408         pm_message_t state)
 409 {
 410         struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
 411
 412         if (main_bat.charge_finished) {
 413                 if (device_may_wakeup(&pdev->dev))
 414                         enable_irq_wake(
 415                                 gpiod_to_irq(main_bat.charge_finished));
 416                 else {
 417                         disable_irq(gpiod_to_irq(main_bat.charge_finished));
 418                         main_bat.pdata->disable_charger();
 419                 }
 420         }
 421
 422         return 0;
 423 }
 424
 425 static int s3c_adc_bat_resume(struct platform_device *pdev)
 426 {
 427         struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
 428
 429         if (main_bat.charge_finished) {
 430                 if (device_may_wakeup(&pdev->dev))
 431                         disable_irq_wake(
 432                                 gpiod_to_irq(main_bat.charge_finished));
 433                 else
 434                         enable_irq(gpiod_to_irq(main_bat.charge_finished));
 435         }
 436
 437         /* Schedule timer to check current status */
 438         schedule_delayed_work(&bat_work,
 439                 msecs_to_jiffies(JITTER_DELAY));
 440
 441         return 0;
 442 }
 443 #else
 444 #define s3c_adc_bat_suspend NULL
 445 #define s3c_adc_bat_resume NULL
 446 #endif
 447
 448 static struct platform_driver s3c_adc_bat_driver = {
 449         .driver         = {
 450                 .name   = "s3c-adc-battery",
 451         },
 452         .probe          = s3c_adc_bat_probe,
 453         .remove         = s3c_adc_bat_remove,
 454         .suspend        = s3c_adc_bat_suspend,
 455         .resume         = s3c_adc_bat_resume,
 456 };
 457
 458 module_platform_driver(s3c_adc_bat_driver);
 459
 460 MODULE_AUTHOR("Vasily Khoruzhick <anarsoul@gmail.com>");
 461 MODULE_DESCRIPTION("iPAQ H1930/H1940/RX1950 battery controller driver");
 462 MODULE_LICENSE("GPL");