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