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