drivers/power/da9030_battery.c

   1 /*
   2  * Battery charger driver for Dialog Semiconductor DA9030
   3  *
   4  * Copyright (C) 2008 Compulab, Ltd.
   5  *      Mike Rapoport <mike@compulab.co.il>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/init.h>
  14 #include <linux/types.h>
  15 #include <linux/device.h>
  16 #include <linux/workqueue.h>
  17 #include <linux/module.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/power_supply.h>
  20 #include <linux/mfd/da903x.h>
  21
  22 #include <linux/debugfs.h>
  23 #include <linux/seq_file.h>
  24
  25 #define DA9030_STATUS_CHDET     (1 << 3)
  26
  27 #define DA9030_FAULT_LOG                0x0a
  28 #define DA9030_FAULT_LOG_OVER_TEMP      (1 << 7)
  29 #define DA9030_FAULT_LOG_VBAT_OVER      (1 << 4)
  30
  31 #define DA9030_CHARGE_CONTROL           0x28
  32 #define DA9030_CHRG_CHARGER_ENABLE      (1 << 7)
  33
  34 #define DA9030_ADC_MAN_CONTROL          0x30
  35 #define DA9030_ADC_TBATREF_ENABLE       (1 << 5)
  36 #define DA9030_ADC_LDO_INT_ENABLE       (1 << 4)
  37
  38 #define DA9030_ADC_AUTO_CONTROL         0x31
  39 #define DA9030_ADC_TBAT_ENABLE          (1 << 5)
  40 #define DA9030_ADC_VBAT_IN_TXON         (1 << 4)
  41 #define DA9030_ADC_VCH_ENABLE           (1 << 3)
  42 #define DA9030_ADC_ICH_ENABLE           (1 << 2)
  43 #define DA9030_ADC_VBAT_ENABLE          (1 << 1)
  44 #define DA9030_ADC_AUTO_SLEEP_ENABLE    (1 << 0)
  45
  46 #define DA9030_VBATMON          0x32
  47 #define DA9030_VBATMONTXON      0x33
  48 #define DA9030_TBATHIGHP        0x34
  49 #define DA9030_TBATHIGHN        0x35
  50 #define DA9030_TBATLOW          0x36
  51
  52 #define DA9030_VBAT_RES         0x41
  53 #define DA9030_VBATMIN_RES      0x42
  54 #define DA9030_VBATMINTXON_RES  0x43
  55 #define DA9030_ICHMAX_RES       0x44
  56 #define DA9030_ICHMIN_RES       0x45
  57 #define DA9030_ICHAVERAGE_RES   0x46
  58 #define DA9030_VCHMAX_RES       0x47
  59 #define DA9030_VCHMIN_RES       0x48
  60 #define DA9030_TBAT_RES         0x49
  61
  62 struct da9030_adc_res {
  63         uint8_t vbat_res;
  64         uint8_t vbatmin_res;
  65         uint8_t vbatmintxon;
  66         uint8_t ichmax_res;
  67         uint8_t ichmin_res;
  68         uint8_t ichaverage_res;
  69         uint8_t vchmax_res;
  70         uint8_t vchmin_res;
  71         uint8_t tbat_res;
  72         uint8_t adc_in4_res;
  73         uint8_t adc_in5_res;
  74 };
  75
  76 struct da9030_battery_thresholds {
  77         int tbat_low;
  78         int tbat_high;
  79         int tbat_restart;
  80
  81         int vbat_low;
  82         int vbat_crit;
  83         int vbat_charge_start;
  84         int vbat_charge_stop;
  85         int vbat_charge_restart;
  86
  87         int vcharge_min;
  88         int vcharge_max;
  89 };
  90
  91 struct da9030_charger {
  92         struct power_supply psy;
  93
  94         struct device *master;
  95
  96         struct da9030_adc_res adc;
  97         struct delayed_work work;
  98         unsigned int interval;
  99
 100         struct power_supply_info *battery_info;
 101
 102         struct da9030_battery_thresholds thresholds;
 103
 104         unsigned int charge_milliamp;
 105         unsigned int charge_millivolt;
 106
 107         /* charger status */
 108         bool chdet;
 109         uint8_t fault;
 110         int mA;
 111         int mV;
 112         bool is_on;
 113
 114         struct notifier_block nb;
 115
 116         /* platform callbacks for battery low and critical events */
 117         void (*battery_low)(void);
 118         void (*battery_critical)(void);
 119
 120         struct dentry *debug_file;
 121 };
 122
 123 static inline int da9030_reg_to_mV(int reg)
 124 {
 125         return ((reg * 2650) >> 8) + 2650;
 126 }
 127
 128 static inline int da9030_millivolt_to_reg(int mV)
 129 {
 130         return ((mV - 2650) << 8) / 2650;
 131 }
 132
 133 static inline int da9030_reg_to_mA(int reg)
 134 {
 135         return ((reg * 24000) >> 8) / 15;
 136 }
 137
 138 #ifdef CONFIG_DEBUG_FS
 139 static int bat_debug_show(struct seq_file *s, void *data)
 140 {
 141         struct da9030_charger *charger = s->private;
 142
 143         seq_printf(s, "charger is %s\n", charger->is_on ? "on" : "off");
 144         if (charger->chdet) {
 145                 seq_printf(s, "iset = %dmA, vset = %dmV\n",
 146                            charger->mA, charger->mV);
 147         }
 148
 149         seq_printf(s, "vbat_res = %d (%dmV)\n",
 150                    charger->adc.vbat_res,
 151                    da9030_reg_to_mV(charger->adc.vbat_res));
 152         seq_printf(s, "vbatmin_res = %d (%dmV)\n",
 153                    charger->adc.vbatmin_res,
 154                    da9030_reg_to_mV(charger->adc.vbatmin_res));
 155         seq_printf(s, "vbatmintxon = %d (%dmV)\n",
 156                    charger->adc.vbatmintxon,
 157                    da9030_reg_to_mV(charger->adc.vbatmintxon));
 158         seq_printf(s, "ichmax_res = %d (%dmA)\n",
 159                    charger->adc.ichmax_res,
 160                    da9030_reg_to_mV(charger->adc.ichmax_res));
 161         seq_printf(s, "ichmin_res = %d (%dmA)\n",
 162                    charger->adc.ichmin_res,
 163                    da9030_reg_to_mA(charger->adc.ichmin_res));
 164         seq_printf(s, "ichaverage_res = %d (%dmA)\n",
 165                    charger->adc.ichaverage_res,
 166                    da9030_reg_to_mA(charger->adc.ichaverage_res));
 167         seq_printf(s, "vchmax_res = %d (%dmV)\n",
 168                    charger->adc.vchmax_res,
 169                    da9030_reg_to_mA(charger->adc.vchmax_res));
 170         seq_printf(s, "vchmin_res = %d (%dmV)\n",
 171                    charger->adc.vchmin_res,
 172                    da9030_reg_to_mV(charger->adc.vchmin_res));
 173
 174         return 0;
 175 }
 176
 177 static int debug_open(struct inode *inode, struct file *file)
 178 {
 179         return single_open(file, bat_debug_show, inode->i_private);
 180 }
 181
 182 static const struct file_operations bat_debug_fops = {
 183         .open           = debug_open,
 184         .read           = seq_read,
 185         .llseek         = seq_lseek,
 186         .release        = single_release,
 187 };
 188
 189 static struct dentry *da9030_bat_create_debugfs(struct da9030_charger *charger)
 190 {
 191         charger->debug_file = debugfs_create_file("charger", 0666, 0, charger,
 192                                                  &bat_debug_fops);
 193         return charger->debug_file;
 194 }
 195
 196 static void da9030_bat_remove_debugfs(struct da9030_charger *charger)
 197 {
 198         debugfs_remove(charger->debug_file);
 199 }
 200 #else
 201 static inline struct dentry *da9030_bat_create_debugfs(struct da9030_charger *charger)
 202 {
 203         return NULL;
 204 }
 205 static inline void da9030_bat_remove_debugfs(struct da9030_charger *charger)
 206 {
 207 }
 208 #endif
 209
 210 static inline void da9030_read_adc(struct da9030_charger *charger,
 211                                    struct da9030_adc_res *adc)
 212 {
 213         da903x_reads(charger->master, DA9030_VBAT_RES,
 214                      sizeof(*adc), (uint8_t *)adc);
 215 }
 216
 217 static void da9030_charger_update_state(struct da9030_charger *charger)
 218 {
 219         uint8_t val;
 220
 221         da903x_read(charger->master, DA9030_CHARGE_CONTROL, &val);
 222         charger->is_on = (val & DA9030_CHRG_CHARGER_ENABLE) ? 1 : 0;
 223         charger->mA = ((val >> 3) & 0xf) * 100;
 224         charger->mV = (val & 0x7) * 50 + 4000;
 225
 226         da9030_read_adc(charger, &charger->adc);
 227         da903x_read(charger->master, DA9030_FAULT_LOG, &charger->fault);
 228         charger->chdet = da903x_query_status(charger->master,
 229                                                      DA9030_STATUS_CHDET);
 230 }
 231
 232 static void da9030_set_charge(struct da9030_charger *charger, int on)
 233 {
 234         uint8_t val;
 235
 236         if (on) {
 237                 val = DA9030_CHRG_CHARGER_ENABLE;
 238                 val |= (charger->charge_milliamp / 100) << 3;
 239                 val |= (charger->charge_millivolt - 4000) / 50;
 240                 charger->is_on = 1;
 241         } else {
 242                 val = 0;
 243                 charger->is_on = 0;
 244         }
 245
 246         da903x_write(charger->master, DA9030_CHARGE_CONTROL, val);
 247 }
 248
 249 static void da9030_charger_check_state(struct da9030_charger *charger)
 250 {
 251         da9030_charger_update_state(charger);
 252
 253         /* we wake or boot with external power on */
 254         if (!charger->is_on) {
 255                 if ((charger->chdet) &&
 256                     (charger->adc.vbat_res <
 257                      charger->thresholds.vbat_charge_start)) {
 258                         da9030_set_charge(charger, 1);
 259                 }
 260         } else {
 261                 if (charger->adc.vbat_res >=
 262                     charger->thresholds.vbat_charge_stop) {
 263                         da9030_set_charge(charger, 0);
 264                         da903x_write(charger->master, DA9030_VBATMON,
 265                                        charger->thresholds.vbat_charge_restart);
 266                 } else if (charger->adc.vbat_res >
 267                            charger->thresholds.vbat_low) {
 268                         /* we are charging and passed LOW_THRESH,
 269                            so upate DA9030 VBAT threshold
 270                          */
 271                         da903x_write(charger->master, DA9030_VBATMON,
 272                                      charger->thresholds.vbat_low);
 273                 }
 274                 if (charger->adc.vchmax_res > charger->thresholds.vcharge_max ||
 275                     charger->adc.vchmin_res < charger->thresholds.vcharge_min ||
 276                     /* Tempreture readings are negative */
 277                     charger->adc.tbat_res < charger->thresholds.tbat_high ||
 278                     charger->adc.tbat_res > charger->thresholds.tbat_low) {
 279                         /* disable charger */
 280                         da9030_set_charge(charger, 0);
 281                 }
 282         }
 283 }
 284
 285 static void da9030_charging_monitor(struct work_struct *work)
 286 {
 287         struct da9030_charger *charger;
 288
 289         charger = container_of(work, struct da9030_charger, work.work);
 290
 291         da9030_charger_check_state(charger);
 292
 293         /* reschedule for the next time */
 294         schedule_delayed_work(&charger->work, charger->interval);
 295 }
 296
 297 static enum power_supply_property da9030_battery_props[] = {
 298         POWER_SUPPLY_PROP_MODEL_NAME,
 299         POWER_SUPPLY_PROP_STATUS,
 300         POWER_SUPPLY_PROP_HEALTH,
 301         POWER_SUPPLY_PROP_TECHNOLOGY,
 302         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
 303         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 304         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 305         POWER_SUPPLY_PROP_CURRENT_AVG,
 306 };
 307
 308 static void da9030_battery_check_status(struct da9030_charger *charger,
 309                                     union power_supply_propval *val)
 310 {
 311         if (charger->chdet) {
 312                 if (charger->is_on)
 313                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 314                 else
 315                         val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
 316         } else {
 317                 val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
 318         }
 319 }
 320
 321 static void da9030_battery_check_health(struct da9030_charger *charger,
 322                                     union power_supply_propval *val)
 323 {
 324         if (charger->fault & DA9030_FAULT_LOG_OVER_TEMP)
 325                 val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
 326         else if (charger->fault & DA9030_FAULT_LOG_VBAT_OVER)
 327                 val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
 328         else
 329                 val->intval = POWER_SUPPLY_HEALTH_GOOD;
 330 }
 331
 332 static int da9030_battery_get_property(struct power_supply *psy,
 333                                    enum power_supply_property psp,
 334                                    union power_supply_propval *val)
 335 {
 336         struct da9030_charger *charger;
 337         charger = container_of(psy, struct da9030_charger, psy);
 338
 339         switch (psp) {
 340         case POWER_SUPPLY_PROP_STATUS:
 341                 da9030_battery_check_status(charger, val);
 342                 break;
 343         case POWER_SUPPLY_PROP_HEALTH:
 344                 da9030_battery_check_health(charger, val);
 345                 break;
 346         case POWER_SUPPLY_PROP_TECHNOLOGY:
 347                 val->intval = charger->battery_info->technology;
 348                 break;
 349         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 350                 val->intval = charger->battery_info->voltage_max_design;
 351                 break;
 352         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 353                 val->intval = charger->battery_info->voltage_min_design;
 354                 break;
 355         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 356                 val->intval = da9030_reg_to_mV(charger->adc.vbat_res) * 1000;
 357                 break;
 358         case POWER_SUPPLY_PROP_CURRENT_AVG:
 359                 val->intval =
 360                         da9030_reg_to_mA(charger->adc.ichaverage_res) * 1000;
 361                 break;
 362         case POWER_SUPPLY_PROP_MODEL_NAME:
 363                 val->strval = charger->battery_info->name;
 364                 break;
 365         default:
 366                 break;
 367         }
 368
 369         return 0;
 370 }
 371
 372 static void da9030_battery_vbat_event(struct da9030_charger *charger)
 373 {
 374         da9030_read_adc(charger, &charger->adc);
 375
 376         if (charger->is_on)
 377                 return;
 378
 379         if (charger->adc.vbat_res < charger->thresholds.vbat_low) {
 380                 /* set VBAT threshold for critical */
 381                 da903x_write(charger->master, DA9030_VBATMON,
 382                              charger->thresholds.vbat_crit);
 383                 if (charger->battery_low)
 384                         charger->battery_low();
 385         } else if (charger->adc.vbat_res <
 386                    charger->thresholds.vbat_crit) {
 387                 /* notify the system of battery critical */
 388                 if (charger->battery_critical)
 389                         charger->battery_critical();
 390         }
 391 }
 392
 393 static int da9030_battery_event(struct notifier_block *nb, unsigned long event,
 394                                 void *data)
 395 {
 396         struct da9030_charger *charger =
 397                 container_of(nb, struct da9030_charger, nb);
 398         int status;
 399
 400         switch (event) {
 401         case DA9030_EVENT_CHDET:
 402                 status = da903x_query_status(charger->master,
 403                                              DA9030_STATUS_CHDET);
 404                 da9030_set_charge(charger, status);
 405                 break;
 406         case DA9030_EVENT_VBATMON:
 407                 da9030_battery_vbat_event(charger);
 408                 break;
 409         case DA9030_EVENT_CHIOVER:
 410         case DA9030_EVENT_TBAT:
 411                 da9030_set_charge(charger, 0);
 412                 break;
 413         }
 414
 415         return 0;
 416 }
 417
 418 static void da9030_battery_convert_thresholds(struct da9030_charger *charger,
 419                                               struct da9030_battery_info *pdata)
 420 {
 421         charger->thresholds.tbat_low = pdata->tbat_low;
 422         charger->thresholds.tbat_high = pdata->tbat_high;
 423         charger->thresholds.tbat_restart  = pdata->tbat_restart;
 424
 425         charger->thresholds.vbat_low =
 426                 da9030_millivolt_to_reg(pdata->vbat_low);
 427         charger->thresholds.vbat_crit =
 428                 da9030_millivolt_to_reg(pdata->vbat_crit);
 429         charger->thresholds.vbat_charge_start =
 430                 da9030_millivolt_to_reg(pdata->vbat_charge_start);
 431         charger->thresholds.vbat_charge_stop =
 432                 da9030_millivolt_to_reg(pdata->vbat_charge_stop);
 433         charger->thresholds.vbat_charge_restart =
 434                 da9030_millivolt_to_reg(pdata->vbat_charge_restart);
 435
 436         charger->thresholds.vcharge_min =
 437                 da9030_millivolt_to_reg(pdata->vcharge_min);
 438         charger->thresholds.vcharge_max =
 439                 da9030_millivolt_to_reg(pdata->vcharge_max);
 440 }
 441
 442 static void da9030_battery_setup_psy(struct da9030_charger *charger)
 443 {
 444         struct power_supply *psy = &charger->psy;
 445         struct power_supply_info *info = charger->battery_info;
 446
 447         psy->name = info->name;
 448         psy->use_for_apm = info->use_for_apm;
 449         psy->type = POWER_SUPPLY_TYPE_BATTERY;
 450         psy->get_property = da9030_battery_get_property;
 451
 452         psy->properties = da9030_battery_props;
 453         psy->num_properties = ARRAY_SIZE(da9030_battery_props);
 454 };
 455
 456 static int da9030_battery_charger_init(struct da9030_charger *charger)
 457 {
 458         char v[5];
 459         int ret;
 460
 461         v[0] = v[1] = charger->thresholds.vbat_low;
 462         v[2] = charger->thresholds.tbat_high;
 463         v[3] = charger->thresholds.tbat_restart;
 464         v[4] = charger->thresholds.tbat_low;
 465
 466         ret = da903x_writes(charger->master, DA9030_VBATMON, 5, v);
 467         if (ret)
 468                 return ret;
 469
 470         /*
 471          * Enable reference voltage supply for ADC from the LDO_INTERNAL
 472          * regulator. Must be set before ADC measurements can be made.
 473          */
 474         ret = da903x_write(charger->master, DA9030_ADC_MAN_CONTROL,
 475                            DA9030_ADC_LDO_INT_ENABLE |
 476                            DA9030_ADC_TBATREF_ENABLE);
 477         if (ret)
 478                 return ret;
 479
 480         /* enable auto ADC measuremnts */
 481         return da903x_write(charger->master, DA9030_ADC_AUTO_CONTROL,
 482                             DA9030_ADC_TBAT_ENABLE | DA9030_ADC_VBAT_IN_TXON |
 483                             DA9030_ADC_VCH_ENABLE | DA9030_ADC_ICH_ENABLE |
 484                             DA9030_ADC_VBAT_ENABLE |
 485                             DA9030_ADC_AUTO_SLEEP_ENABLE);
 486 }
 487
 488 static int da9030_battery_probe(struct platform_device *pdev)
 489 {
 490         struct da9030_charger *charger;
 491         struct da9030_battery_info *pdata = pdev->dev.platform_data;
 492         int ret;
 493
 494         if (pdata == NULL)
 495                 return -EINVAL;
 496
 497         if (pdata->charge_milliamp >= 1500 ||
 498             pdata->charge_millivolt < 4000 ||
 499             pdata->charge_millivolt > 4350)
 500                 return -EINVAL;
 501
 502         charger = kzalloc(sizeof(*charger), GFP_KERNEL);
 503         if (charger == NULL)
 504                 return -ENOMEM;
 505
 506         charger->master = pdev->dev.parent;
 507
 508         /* 10 seconds between monotor runs unless platfrom defines other
 509            interval */
 510         charger->interval = msecs_to_jiffies(
 511                 (pdata->batmon_interval ? : 10) * 1000);
 512
 513         charger->charge_milliamp = pdata->charge_milliamp;
 514         charger->charge_millivolt = pdata->charge_millivolt;
 515         charger->battery_info = pdata->battery_info;
 516         charger->battery_low = pdata->battery_low;
 517         charger->battery_critical = pdata->battery_critical;
 518
 519         da9030_battery_convert_thresholds(charger, pdata);
 520
 521         ret = da9030_battery_charger_init(charger);
 522         if (ret)
 523                 goto err_charger_init;
 524
 525         INIT_DELAYED_WORK(&charger->work, da9030_charging_monitor);
 526         schedule_delayed_work(&charger->work, charger->interval);
 527
 528         charger->nb.notifier_call = da9030_battery_event;
 529         ret = da903x_register_notifier(charger->master, &charger->nb,
 530                                        DA9030_EVENT_CHDET |
 531                                        DA9030_EVENT_VBATMON |
 532                                        DA9030_EVENT_CHIOVER |
 533                                        DA9030_EVENT_TBAT);
 534         if (ret)
 535                 goto err_notifier;
 536
 537         da9030_battery_setup_psy(charger);
 538         ret = power_supply_register(&pdev->dev, &charger->psy);
 539         if (ret)
 540                 goto err_ps_register;
 541
 542         charger->debug_file = da9030_bat_create_debugfs(charger);
 543         platform_set_drvdata(pdev, charger);
 544         return 0;
 545
 546 err_ps_register:
 547         da903x_unregister_notifier(charger->master, &charger->nb,
 548                                    DA9030_EVENT_CHDET | DA9030_EVENT_VBATMON |
 549                                    DA9030_EVENT_CHIOVER | DA9030_EVENT_TBAT);
 550 err_notifier:
 551         cancel_delayed_work(&charger->work);
 552
 553 err_charger_init:
 554         kfree(charger);
 555
 556         return ret;
 557 }
 558
 559 static int da9030_battery_remove(struct platform_device *dev)
 560 {
 561         struct da9030_charger *charger = platform_get_drvdata(dev);
 562
 563         da9030_bat_remove_debugfs(charger);
 564
 565         da903x_unregister_notifier(charger->master, &charger->nb,
 566                                    DA9030_EVENT_CHDET | DA9030_EVENT_VBATMON |
 567                                    DA9030_EVENT_CHIOVER | DA9030_EVENT_TBAT);
 568         cancel_delayed_work(&charger->work);
 569         power_supply_unregister(&charger->psy);
 570
 571         kfree(charger);
 572
 573         return 0;
 574 }
 575
 576 static struct platform_driver da903x_battery_driver = {
 577         .driver = {
 578                 .name   = "da903x-battery",
 579                 .owner  = THIS_MODULE,
 580         },
 581         .probe = da9030_battery_probe,
 582         .remove = da9030_battery_remove,
 583 };
 584
 585 static int da903x_battery_init(void)
 586 {
 587         return platform_driver_register(&da903x_battery_driver);
 588 }
 589
 590 static void da903x_battery_exit(void)
 591 {
 592         platform_driver_unregister(&da903x_battery_driver);
 593 }
 594
 595 module_init(da903x_battery_init);
 596 module_exit(da903x_battery_exit);
 597
 598 MODULE_DESCRIPTION("DA9030 battery charger driver");
 599 MODULE_AUTHOR("Mike Rapoport, CompuLab");
 600 MODULE_LICENSE("GPL");