drivers/power/supply/s3c_adc_battery.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 //
   3 // iPAQ h1930/h1940/rx1950 battery controller driver
   4 // Copyright (c) Vasily Khoruzhick
   5 // Based on h1940_battery.c by Arnaud Patard
   6
   7 #include <linux/interrupt.h>
   8 #include <linux/platform_device.h>
   9 #include <linux/power_supply.h>
  10 #include <linux/leds.h>
  11 #include <linux/gpio/consumer.h>
  12 #include <linux/err.h>
  13 #include <linux/timer.h>
  14 #include <linux/jiffies.h>
  15 #include <linux/s3c_adc_battery.h>
  16 #include <linux/errno.h>
  17 #include <linux/init.h>
  18 #include <linux/module.h>
  19
  20 #include <linux/soc/samsung/s3c-adc.h>
  21
  22 #define BAT_POLL_INTERVAL               10000 /* ms */
  23 #define JITTER_DELAY                    500 /* ms */
  24
  25 struct s3c_adc_bat {
  26         struct power_supply             *psy;
  27         struct s3c_adc_client           *client;
  28         struct s3c_adc_bat_pdata        *pdata;
  29         struct gpio_desc                *charge_finished;
  30         int                             volt_value;
  31         int                             cur_value;
  32         unsigned int                    timestamp;
  33         int                             level;
  34         int                             status;
  35         int                             cable_plugged:1;
  36 };
  37
  38 static struct delayed_work bat_work;
  39
  40 static void s3c_adc_bat_ext_power_changed(struct power_supply *psy)
  41 {
  42         schedule_delayed_work(&bat_work,
  43                 msecs_to_jiffies(JITTER_DELAY));
  44 }
  45
  46 static int gather_samples(struct s3c_adc_client *client, int num, int channel)
  47 {
  48         int value, i;
  49
  50         /* default to 1 if nothing is set */
  51         if (num < 1)
  52                 num = 1;
  53
  54         value = 0;
  55         for (i = 0; i < num; i++)
  56                 value += s3c_adc_read(client, channel);
  57         value /= num;
  58
  59         return value;
  60 }
  61
  62 static enum power_supply_property s3c_adc_backup_bat_props[] = {
  63         POWER_SUPPLY_PROP_VOLTAGE_NOW,
  64         POWER_SUPPLY_PROP_VOLTAGE_MIN,
  65         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
  66 };
  67
  68 static int s3c_adc_backup_bat_get_property(struct power_supply *psy,
  69                                 enum power_supply_property psp,
  70                                 union power_supply_propval *val)
  71 {
  72         struct s3c_adc_bat *bat = power_supply_get_drvdata(psy);
  73
  74         if (!bat) {
  75                 dev_err(&psy->dev, "%s: no battery infos ?!\n", __func__);
  76                 return -EINVAL;
  77         }
  78
  79         if (bat->volt_value < 0 ||
  80                 jiffies_to_msecs(jiffies - bat->timestamp) >
  81                         BAT_POLL_INTERVAL) {
  82                 bat->volt_value = gather_samples(bat->client,
  83                         bat->pdata->backup_volt_samples,
  84                         bat->pdata->backup_volt_channel);
  85                 bat->volt_value *= bat->pdata->backup_volt_mult;
  86                 bat->timestamp = jiffies;
  87         }
  88
  89         switch (psp) {
  90         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
  91                 val->intval = bat->volt_value;
  92                 return 0;
  93         case POWER_SUPPLY_PROP_VOLTAGE_MIN:
  94                 val->intval = bat->pdata->backup_volt_min;
  95                 return 0;
  96         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
  97                 val->intval = bat->pdata->backup_volt_max;
  98                 return 0;
  99         default:
 100                 return -EINVAL;
 101         }
 102 }
 103
 104 static const struct power_supply_desc backup_bat_desc = {
 105         .name           = "backup-battery",
 106         .type           = POWER_SUPPLY_TYPE_BATTERY,
 107         .properties     = s3c_adc_backup_bat_props,
 108         .num_properties = ARRAY_SIZE(s3c_adc_backup_bat_props),
 109         .get_property   = s3c_adc_backup_bat_get_property,
 110         .use_for_apm    = 1,
 111 };
 112
 113 static struct s3c_adc_bat backup_bat;
 114
 115 static enum power_supply_property s3c_adc_main_bat_props[] = {
 116         POWER_SUPPLY_PROP_STATUS,
 117         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 118         POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
 119         POWER_SUPPLY_PROP_CHARGE_NOW,
 120         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 121         POWER_SUPPLY_PROP_CURRENT_NOW,
 122 };
 123
 124 static int calc_full_volt(int volt_val, int cur_val, int impedance)
 125 {
 126         return volt_val + cur_val * impedance / 1000;
 127 }
 128
 129 static int charge_finished(struct s3c_adc_bat *bat)
 130 {
 131         return gpiod_get_value(bat->charge_finished);
 132 }
 133
 134 static int s3c_adc_bat_get_property(struct power_supply *psy,
 135                                     enum power_supply_property psp,
 136                                     union power_supply_propval *val)
 137 {
 138         struct s3c_adc_bat *bat = power_supply_get_drvdata(psy);
 139
 140         int new_level;
 141         int full_volt;
 142         const struct s3c_adc_bat_thresh *lut;
 143         unsigned int lut_size;
 144
 145         if (!bat) {
 146                 dev_err(&psy->dev, "no battery infos ?!\n");
 147                 return -EINVAL;
 148         }
 149
 150         lut = bat->pdata->lut_noac;
 151         lut_size = bat->pdata->lut_noac_cnt;
 152
 153         if (bat->volt_value < 0 || bat->cur_value < 0 ||
 154                 jiffies_to_msecs(jiffies - bat->timestamp) >
 155                         BAT_POLL_INTERVAL) {
 156                 bat->volt_value = gather_samples(bat->client,
 157                         bat->pdata->volt_samples,
 158                         bat->pdata->volt_channel) * bat->pdata->volt_mult;
 159                 bat->cur_value = gather_samples(bat->client,
 160                         bat->pdata->current_samples,
 161                         bat->pdata->current_channel) * bat->pdata->current_mult;
 162                 bat->timestamp = jiffies;
 163         }
 164
 165         if (bat->cable_plugged &&
 166                 (!bat->charge_finished ||
 167                 !charge_finished(bat))) {
 168                 lut = bat->pdata->lut_acin;
 169                 lut_size = bat->pdata->lut_acin_cnt;
 170         }
 171
 172         new_level = 100000;
 173         full_volt = calc_full_volt((bat->volt_value / 1000),
 174                 (bat->cur_value / 1000), bat->pdata->internal_impedance);
 175
 176         if (full_volt < calc_full_volt(lut->volt, lut->cur,
 177                 bat->pdata->internal_impedance)) {
 178                 lut_size--;
 179                 while (lut_size--) {
 180                         int lut_volt1;
 181                         int lut_volt2;
 182
 183                         lut_volt1 = calc_full_volt(lut[0].volt, lut[0].cur,
 184                                 bat->pdata->internal_impedance);
 185                         lut_volt2 = calc_full_volt(lut[1].volt, lut[1].cur,
 186                                 bat->pdata->internal_impedance);
 187                         if (full_volt < lut_volt1 && full_volt >= lut_volt2) {
 188                                 new_level = (lut[1].level +
 189                                         (lut[0].level - lut[1].level) *
 190                                         (full_volt - lut_volt2) /
 191                                         (lut_volt1 - lut_volt2)) * 1000;
 192                                 break;
 193                         }
 194                         new_level = lut[1].level * 1000;
 195                         lut++;
 196                 }
 197         }
 198
 199         bat->level = new_level;
 200
 201         switch (psp) {
 202         case POWER_SUPPLY_PROP_STATUS:
 203                 if (!bat->charge_finished)
 204                         val->intval = bat->level == 100000 ?
 205                                 POWER_SUPPLY_STATUS_FULL : bat->status;
 206                 else
 207                         val->intval = bat->status;
 208                 return 0;
 209         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 210                 val->intval = 100000;
 211                 return 0;
 212         case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
 213                 val->intval = 0;
 214                 return 0;
 215         case POWER_SUPPLY_PROP_CHARGE_NOW:
 216                 val->intval = bat->level;
 217                 return 0;
 218         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 219                 val->intval = bat->volt_value;
 220                 return 0;
 221         case POWER_SUPPLY_PROP_CURRENT_NOW:
 222                 val->intval = bat->cur_value;
 223                 return 0;
 224         default:
 225                 return -EINVAL;
 226         }
 227 }
 228
 229 static const struct power_supply_desc main_bat_desc = {
 230         .name                   = "main-battery",
 231         .type                   = POWER_SUPPLY_TYPE_BATTERY,
 232         .properties             = s3c_adc_main_bat_props,
 233         .num_properties         = ARRAY_SIZE(s3c_adc_main_bat_props),
 234         .get_property           = s3c_adc_bat_get_property,
 235         .external_power_changed = s3c_adc_bat_ext_power_changed,
 236         .use_for_apm            = 1,
 237 };
 238
 239 static struct s3c_adc_bat main_bat;
 240
 241 static void s3c_adc_bat_work(struct work_struct *work)
 242 {
 243         struct s3c_adc_bat *bat = &main_bat;
 244         int is_charged;
 245         int is_plugged;
 246         static int was_plugged;
 247
 248         is_plugged = power_supply_am_i_supplied(bat->psy);
 249         bat->cable_plugged = is_plugged;
 250         if (is_plugged != was_plugged) {
 251                 was_plugged = is_plugged;
 252                 if (is_plugged) {
 253                         if (bat->pdata->enable_charger)
 254                                 bat->pdata->enable_charger();
 255                         bat->status = POWER_SUPPLY_STATUS_CHARGING;
 256                 } else {
 257                         if (bat->pdata->disable_charger)
 258                                 bat->pdata->disable_charger();
 259                         bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
 260                 }
 261         } else {
 262                 if (bat->charge_finished && is_plugged) {
 263                         is_charged = charge_finished(&main_bat);
 264                         if (is_charged) {
 265                                 if (bat->pdata->disable_charger)
 266                                         bat->pdata->disable_charger();
 267                                 bat->status = POWER_SUPPLY_STATUS_FULL;
 268                         } else {
 269                                 if (bat->pdata->enable_charger)
 270                                         bat->pdata->enable_charger();
 271                                 bat->status = POWER_SUPPLY_STATUS_CHARGING;
 272                         }
 273                 }
 274         }
 275
 276         power_supply_changed(bat->psy);
 277 }
 278
 279 static irqreturn_t s3c_adc_bat_charged(int irq, void *dev_id)
 280 {
 281         schedule_delayed_work(&bat_work,
 282                 msecs_to_jiffies(JITTER_DELAY));
 283         return IRQ_HANDLED;
 284 }
 285
 286 static int s3c_adc_bat_probe(struct platform_device *pdev)
 287 {
 288         struct s3c_adc_client   *client;
 289         struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
 290         struct power_supply_config psy_cfg = {};
 291         struct gpio_desc *gpiod;
 292         int ret;
 293
 294         client = s3c_adc_register(pdev, NULL, NULL, 0);
 295         if (IS_ERR(client)) {
 296                 dev_err(&pdev->dev, "cannot register adc\n");
 297                 return PTR_ERR(client);
 298         }
 299
 300         platform_set_drvdata(pdev, client);
 301
 302         gpiod = devm_gpiod_get_optional(&pdev->dev, "charge-status", GPIOD_IN);
 303         if (IS_ERR(gpiod)) {
 304                 /* Could be probe deferral etc */
 305                 ret = PTR_ERR(gpiod);
 306                 dev_err(&pdev->dev, "no GPIO %d\n", ret);
 307                 return ret;
 308         }
 309
 310         main_bat.client = client;
 311         main_bat.pdata = pdata;
 312         main_bat.charge_finished = gpiod;
 313         main_bat.volt_value = -1;
 314         main_bat.cur_value = -1;
 315         main_bat.cable_plugged = 0;
 316         main_bat.status = POWER_SUPPLY_STATUS_DISCHARGING;
 317         psy_cfg.drv_data = &main_bat;
 318
 319         main_bat.psy = power_supply_register(&pdev->dev, &main_bat_desc, &psy_cfg);
 320         if (IS_ERR(main_bat.psy)) {
 321                 ret = PTR_ERR(main_bat.psy);
 322                 goto err_reg_main;
 323         }
 324         if (pdata->backup_volt_mult) {
 325                 const struct power_supply_config backup_psy_cfg
 326                                                 = { .drv_data = &backup_bat, };
 327
 328                 backup_bat.client = client;
 329                 backup_bat.pdata = pdev->dev.platform_data;
 330                 backup_bat.charge_finished = gpiod;
 331                 backup_bat.volt_value = -1;
 332                 backup_bat.psy = power_supply_register(&pdev->dev,
 333                                                        &backup_bat_desc,
 334                                                        &backup_psy_cfg);
 335                 if (IS_ERR(backup_bat.psy)) {
 336                         ret = PTR_ERR(backup_bat.psy);
 337                         goto err_reg_backup;
 338                 }
 339         }
 340
 341         INIT_DELAYED_WORK(&bat_work, s3c_adc_bat_work);
 342
 343         if (gpiod) {
 344                 ret = request_irq(gpiod_to_irq(gpiod),
 345                                 s3c_adc_bat_charged,
 346                                 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 347                                 "battery charged", NULL);
 348                 if (ret)
 349                         goto err_irq;
 350         }
 351
 352         if (pdata->init) {
 353                 ret = pdata->init();
 354                 if (ret)
 355                         goto err_platform;
 356         }
 357
 358         dev_info(&pdev->dev, "successfully loaded\n");
 359         device_init_wakeup(&pdev->dev, 1);
 360
 361         /* Schedule timer to check current status */
 362         schedule_delayed_work(&bat_work,
 363                 msecs_to_jiffies(JITTER_DELAY));
 364
 365         return 0;
 366
 367 err_platform:
 368         if (gpiod)
 369                 free_irq(gpiod_to_irq(gpiod), NULL);
 370 err_irq:
 371         if (pdata->backup_volt_mult)
 372                 power_supply_unregister(backup_bat.psy);
 373 err_reg_backup:
 374         power_supply_unregister(main_bat.psy);
 375 err_reg_main:
 376         return ret;
 377 }
 378
 379 static int s3c_adc_bat_remove(struct platform_device *pdev)
 380 {
 381         struct s3c_adc_client *client = platform_get_drvdata(pdev);
 382         struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
 383
 384         power_supply_unregister(main_bat.psy);
 385         if (pdata->backup_volt_mult)
 386                 power_supply_unregister(backup_bat.psy);
 387
 388         s3c_adc_release(client);
 389
 390         if (main_bat.charge_finished)
 391                 free_irq(gpiod_to_irq(main_bat.charge_finished), NULL);
 392
 393         cancel_delayed_work_sync(&bat_work);
 394
 395         if (pdata->exit)
 396                 pdata->exit();
 397
 398         return 0;
 399 }
 400
 401 #ifdef CONFIG_PM
 402 static int s3c_adc_bat_suspend(struct platform_device *pdev,
 403         pm_message_t state)
 404 {
 405         if (main_bat.charge_finished) {
 406                 if (device_may_wakeup(&pdev->dev))
 407                         enable_irq_wake(
 408                                 gpiod_to_irq(main_bat.charge_finished));
 409                 else {
 410                         disable_irq(gpiod_to_irq(main_bat.charge_finished));
 411                         main_bat.pdata->disable_charger();
 412                 }
 413         }
 414
 415         return 0;
 416 }
 417
 418 static int s3c_adc_bat_resume(struct platform_device *pdev)
 419 {
 420         if (main_bat.charge_finished) {
 421                 if (device_may_wakeup(&pdev->dev))
 422                         disable_irq_wake(
 423                                 gpiod_to_irq(main_bat.charge_finished));
 424                 else
 425                         enable_irq(gpiod_to_irq(main_bat.charge_finished));
 426         }
 427
 428         /* Schedule timer to check current status */
 429         schedule_delayed_work(&bat_work,
 430                 msecs_to_jiffies(JITTER_DELAY));
 431
 432         return 0;
 433 }
 434 #else
 435 #define s3c_adc_bat_suspend NULL
 436 #define s3c_adc_bat_resume NULL
 437 #endif
 438
 439 static struct platform_driver s3c_adc_bat_driver = {
 440         .driver         = {
 441                 .name   = "s3c-adc-battery",
 442         },
 443         .probe          = s3c_adc_bat_probe,
 444         .remove         = s3c_adc_bat_remove,
 445         .suspend        = s3c_adc_bat_suspend,
 446         .resume         = s3c_adc_bat_resume,
 447 };
 448
 449 module_platform_driver(s3c_adc_bat_driver);
 450
 451 MODULE_AUTHOR("Vasily Khoruzhick <anarsoul@gmail.com>");
 452 MODULE_DESCRIPTION("iPAQ H1930/H1940/RX1950 battery controller driver");
 453 MODULE_LICENSE("GPL");