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_FAULT_LOG                0x0a
  26 #define DA9030_FAULT_LOG_OVER_TEMP      (1 << 7)
  27 #define DA9030_FAULT_LOG_VBAT_OVER      (1 << 4)
  28
  29 #define DA9030_CHARGE_CONTROL           0x28
  30 #define DA9030_CHRG_CHARGER_ENABLE      (1 << 7)
  31
  32 #define DA9030_ADC_MAN_CONTROL          0x30
  33 #define DA9030_ADC_TBATREF_ENABLE       (1 << 5)
  34 #define DA9030_ADC_LDO_INT_ENABLE       (1 << 4)
  35
  36 #define DA9030_ADC_AUTO_CONTROL         0x31
  37 #define DA9030_ADC_TBAT_ENABLE          (1 << 5)
  38 #define DA9030_ADC_VBAT_IN_TXON         (1 << 4)
  39 #define DA9030_ADC_VCH_ENABLE           (1 << 3)
  40 #define DA9030_ADC_ICH_ENABLE           (1 << 2)
  41 #define DA9030_ADC_VBAT_ENABLE          (1 << 1)
  42 #define DA9030_ADC_AUTO_SLEEP_ENABLE    (1 << 0)
  43
  44 #define DA9030_VBATMON          0x32
  45 #define DA9030_VBATMONTXON      0x33
  46 #define DA9030_TBATHIGHP        0x34
  47 #define DA9030_TBATHIGHN        0x35
  48 #define DA9030_TBATLOW          0x36
  49
  50 #define DA9030_VBAT_RES         0x41
  51 #define DA9030_VBATMIN_RES      0x42
  52 #define DA9030_VBATMINTXON_RES  0x43
  53 #define DA9030_ICHMAX_RES       0x44
  54 #define DA9030_ICHMIN_RES       0x45
  55 #define DA9030_ICHAVERAGE_RES   0x46
  56 #define DA9030_VCHMAX_RES       0x47
  57 #define DA9030_VCHMIN_RES       0x48
  58 #define DA9030_TBAT_RES         0x49
  59
  60 struct da9030_adc_res {
  61         uint8_t vbat_res;
  62         uint8_t vbatmin_res;
  63         uint8_t vbatmintxon;
  64         uint8_t ichmax_res;
  65         uint8_t ichmin_res;
  66         uint8_t ichaverage_res;
  67         uint8_t vchmax_res;
  68         uint8_t vchmin_res;
  69         uint8_t tbat_res;
  70         uint8_t adc_in4_res;
  71         uint8_t adc_in5_res;
  72 };
  73
  74 struct da9030_battery_thresholds {
  75         int tbat_low;
  76         int tbat_high;
  77         int tbat_restart;
  78
  79         int vbat_low;
  80         int vbat_crit;
  81         int vbat_charge_start;
  82         int vbat_charge_stop;
  83         int vbat_charge_restart;
  84
  85         int vcharge_min;
  86         int vcharge_max;
  87 };
  88
  89 struct da9030_charger {
  90         struct power_supply psy;
  91
  92         struct device *master;
  93
  94         struct da9030_adc_res adc;
  95         struct delayed_work work;
  96         unsigned int interval;
  97
  98         struct power_supply_info *battery_info;
  99
 100         struct da9030_battery_thresholds thresholds;
 101
 102         unsigned int charge_milliamp;
 103         unsigned int charge_millivolt;
 104
 105         /* charger status */
 106         bool chdet;
 107         uint8_t fault;
 108         int mA;
 109         int mV;
 110         bool is_on;
 111
 112         struct notifier_block nb;
 113
 114         /* platform callbacks for battery low and critical events */
 115         void (*battery_low)(void);
 116         void (*battery_critical)(void);
 117
 118         struct dentry *debug_file;
 119 };
 120
 121 static inline int da9030_reg_to_mV(int reg)
 122 {
 123         return ((reg * 2650) >> 8) + 2650;
 124 }
 125
 126 static inline int da9030_millivolt_to_reg(int mV)
 127 {
 128         return ((mV - 2650) << 8) / 2650;
 129 }
 130
 131 static inline int da9030_reg_to_mA(int reg)
 132 {
 133         return ((reg * 24000) >> 8) / 15;
 134 }
 135
 136 #ifdef CONFIG_DEBUG_FS
 137 static int bat_debug_show(struct seq_file *s, void *data)
 138 {
 139         struct da9030_charger *charger = s->private;
 140
 141         seq_printf(s, "charger is %s\n", charger->is_on ? "on" : "off");
 142         if (charger->chdet) {
 143                 seq_printf(s, "iset = %dmA, vset = %dmV\n",
 144                            charger->mA, charger->mV);
 145         }
 146
 147         seq_printf(s, "vbat_res = %d (%dmV)\n",
 148                    charger->adc.vbat_res,
 149                    da9030_reg_to_mV(charger->adc.vbat_res));
 150         seq_printf(s, "vbatmin_res = %d (%dmV)\n",
 151                    charger->adc.vbatmin_res,
 152                    da9030_reg_to_mV(charger->adc.vbatmin_res));
 153         seq_printf(s, "vbatmintxon = %d (%dmV)\n",
 154                    charger->adc.vbatmintxon,
 155                    da9030_reg_to_mV(charger->adc.vbatmintxon));
 156         seq_printf(s, "ichmax_res = %d (%dmA)\n",
 157                    charger->adc.ichmax_res,
 158                    da9030_reg_to_mV(charger->adc.ichmax_res));
 159         seq_printf(s, "ichmin_res = %d (%dmA)\n",
 160                    charger->adc.ichmin_res,
 161                    da9030_reg_to_mA(charger->adc.ichmin_res));
 162         seq_printf(s, "ichaverage_res = %d (%dmA)\n",
 163                    charger->adc.ichaverage_res,
 164                    da9030_reg_to_mA(charger->adc.ichaverage_res));
 165         seq_printf(s, "vchmax_res = %d (%dmV)\n",
 166                    charger->adc.vchmax_res,
 167                    da9030_reg_to_mA(charger->adc.vchmax_res));
 168         seq_printf(s, "vchmin_res = %d (%dmV)\n",
 169                    charger->adc.vchmin_res,
 170                    da9030_reg_to_mV(charger->adc.vchmin_res));
 171
 172         return 0;
 173 }
 174
 175 static int debug_open(struct inode *inode, struct file *file)
 176 {
 177         return single_open(file, bat_debug_show, inode->i_private);
 178 }
 179
 180 static const struct file_operations bat_debug_fops = {
 181         .open           = debug_open,
 182         .read           = seq_read,
 183         .llseek         = seq_lseek,
 184         .release        = single_release,
 185 };
 186
 187 static struct dentry *da9030_bat_create_debugfs(struct da9030_charger *charger)
 188 {
 189         charger->debug_file = debugfs_create_file("charger", 0666, 0, charger,
 190                                                  &bat_debug_fops);
 191         return charger->debug_file;
 192 }
 193
 194 static void da9030_bat_remove_debugfs(struct da9030_charger *charger)
 195 {
 196         debugfs_remove(charger->debug_file);
 197 }
 198 #else
 199 static inline struct dentry *da9030_bat_create_debugfs(struct da9030_charger *charger)
 200 {
 201         return NULL;
 202 }
 203 static inline void da9030_bat_remove_debugfs(struct da9030_charger *charger)
 204 {
 205 }
 206 #endif
 207
 208 static inline void da9030_read_adc(struct da9030_charger *charger,
 209                                    struct da9030_adc_res *adc)
 210 {
 211         da903x_reads(charger->master, DA9030_VBAT_RES,
 212                      sizeof(*adc), (uint8_t *)adc);
 213 }
 214
 215 static void da9030_charger_update_state(struct da9030_charger *charger)
 216 {
 217         uint8_t val;
 218
 219         da903x_read(charger->master, DA9030_CHARGE_CONTROL, &val);
 220         charger->is_on = (val & DA9030_CHRG_CHARGER_ENABLE) ? 1 : 0;
 221         charger->mA = ((val >> 3) & 0xf) * 100;
 222         charger->mV = (val & 0x7) * 50 + 4000;
 223
 224         da9030_read_adc(charger, &charger->adc);
 225         da903x_read(charger->master, DA9030_FAULT_LOG, &charger->fault);
 226         charger->chdet = da903x_query_status(charger->master,
 227                                                      DA9030_STATUS_CHDET);
 228 }
 229
 230 static void da9030_set_charge(struct da9030_charger *charger, int on)
 231 {
 232         uint8_t val;
 233
 234         if (on) {
 235                 val = DA9030_CHRG_CHARGER_ENABLE;
 236                 val |= (charger->charge_milliamp / 100) << 3;
 237                 val |= (charger->charge_millivolt - 4000) / 50;
 238                 charger->is_on = 1;
 239         } else {
 240                 val = 0;
 241                 charger->is_on = 0;
 242         }
 243
 244         da903x_write(charger->master, DA9030_CHARGE_CONTROL, val);
 245
 246         power_supply_changed(&charger->psy);
 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                 /* Charger has been pulled out */
 262                 if (!charger->chdet) {
 263                         da9030_set_charge(charger, 0);
 264                         return;
 265                 }
 266
 267                 if (charger->adc.vbat_res >=
 268                     charger->thresholds.vbat_charge_stop) {
 269                         da9030_set_charge(charger, 0);
 270                         da903x_write(charger->master, DA9030_VBATMON,
 271                                        charger->thresholds.vbat_charge_restart);
 272                 } else if (charger->adc.vbat_res >
 273                            charger->thresholds.vbat_low) {
 274                         /* we are charging and passed LOW_THRESH,
 275                            so upate DA9030 VBAT threshold
 276                          */
 277                         da903x_write(charger->master, DA9030_VBATMON,
 278                                      charger->thresholds.vbat_low);
 279                 }
 280                 if (charger->adc.vchmax_res > charger->thresholds.vcharge_max ||
 281                     charger->adc.vchmin_res < charger->thresholds.vcharge_min ||
 282                     /* Tempreture readings are negative */
 283                     charger->adc.tbat_res < charger->thresholds.tbat_high ||
 284                     charger->adc.tbat_res > charger->thresholds.tbat_low) {
 285                         /* disable charger */
 286                         da9030_set_charge(charger, 0);
 287                 }
 288         }
 289 }
 290
 291 static void da9030_charging_monitor(struct work_struct *work)
 292 {
 293         struct da9030_charger *charger;
 294
 295         charger = container_of(work, struct da9030_charger, work.work);
 296
 297         da9030_charger_check_state(charger);
 298
 299         /* reschedule for the next time */
 300         schedule_delayed_work(&charger->work, charger->interval);
 301 }
 302
 303 static enum power_supply_property da9030_battery_props[] = {
 304         POWER_SUPPLY_PROP_MODEL_NAME,
 305         POWER_SUPPLY_PROP_STATUS,
 306         POWER_SUPPLY_PROP_HEALTH,
 307         POWER_SUPPLY_PROP_TECHNOLOGY,
 308         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
 309         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 310         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 311         POWER_SUPPLY_PROP_CURRENT_AVG,
 312 };
 313
 314 static void da9030_battery_check_status(struct da9030_charger *charger,
 315                                     union power_supply_propval *val)
 316 {
 317         if (charger->chdet) {
 318                 if (charger->is_on)
 319                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 320                 else
 321                         val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
 322         } else {
 323                 val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
 324         }
 325 }
 326
 327 static void da9030_battery_check_health(struct da9030_charger *charger,
 328                                     union power_supply_propval *val)
 329 {
 330         if (charger->fault & DA9030_FAULT_LOG_OVER_TEMP)
 331                 val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
 332         else if (charger->fault & DA9030_FAULT_LOG_VBAT_OVER)
 333                 val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
 334         else
 335                 val->intval = POWER_SUPPLY_HEALTH_GOOD;
 336 }
 337
 338 static int da9030_battery_get_property(struct power_supply *psy,
 339                                    enum power_supply_property psp,
 340                                    union power_supply_propval *val)
 341 {
 342         struct da9030_charger *charger;
 343         charger = container_of(psy, struct da9030_charger, psy);
 344
 345         switch (psp) {
 346         case POWER_SUPPLY_PROP_STATUS:
 347                 da9030_battery_check_status(charger, val);
 348                 break;
 349         case POWER_SUPPLY_PROP_HEALTH:
 350                 da9030_battery_check_health(charger, val);
 351                 break;
 352         case POWER_SUPPLY_PROP_TECHNOLOGY:
 353                 val->intval = charger->battery_info->technology;
 354                 break;
 355         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 356                 val->intval = charger->battery_info->voltage_max_design;
 357                 break;
 358         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 359                 val->intval = charger->battery_info->voltage_min_design;
 360                 break;
 361         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 362                 val->intval = da9030_reg_to_mV(charger->adc.vbat_res) * 1000;
 363                 break;
 364         case POWER_SUPPLY_PROP_CURRENT_AVG:
 365                 val->intval =
 366                         da9030_reg_to_mA(charger->adc.ichaverage_res) * 1000;
 367                 break;
 368         case POWER_SUPPLY_PROP_MODEL_NAME:
 369                 val->strval = charger->battery_info->name;
 370                 break;
 371         default:
 372                 break;
 373         }
 374
 375         return 0;
 376 }
 377
 378 static void da9030_battery_vbat_event(struct da9030_charger *charger)
 379 {
 380         da9030_read_adc(charger, &charger->adc);
 381
 382         if (charger->is_on)
 383                 return;
 384
 385         if (charger->adc.vbat_res < charger->thresholds.vbat_low) {
 386                 /* set VBAT threshold for critical */
 387                 da903x_write(charger->master, DA9030_VBATMON,
 388                              charger->thresholds.vbat_crit);
 389                 if (charger->battery_low)
 390                         charger->battery_low();
 391         } else if (charger->adc.vbat_res <
 392                    charger->thresholds.vbat_crit) {
 393                 /* notify the system of battery critical */
 394                 if (charger->battery_critical)
 395                         charger->battery_critical();
 396         }
 397 }
 398
 399 static int da9030_battery_event(struct notifier_block *nb, unsigned long event,
 400                                 void *data)
 401 {
 402         struct da9030_charger *charger =
 403                 container_of(nb, struct da9030_charger, nb);
 404
 405         switch (event) {
 406         case DA9030_EVENT_CHDET:
 407                 cancel_delayed_work_sync(&charger->work);
 408                 schedule_work(&charger->work.work);
 409                 break;
 410         case DA9030_EVENT_VBATMON:
 411                 da9030_battery_vbat_event(charger);
 412                 break;
 413         case DA9030_EVENT_CHIOVER:
 414         case DA9030_EVENT_TBAT:
 415                 da9030_set_charge(charger, 0);
 416                 break;
 417         }
 418
 419         return 0;
 420 }
 421
 422 static void da9030_battery_convert_thresholds(struct da9030_charger *charger,
 423                                               struct da9030_battery_info *pdata)
 424 {
 425         charger->thresholds.tbat_low = pdata->tbat_low;
 426         charger->thresholds.tbat_high = pdata->tbat_high;
 427         charger->thresholds.tbat_restart  = pdata->tbat_restart;
 428
 429         charger->thresholds.vbat_low =
 430                 da9030_millivolt_to_reg(pdata->vbat_low);
 431         charger->thresholds.vbat_crit =
 432                 da9030_millivolt_to_reg(pdata->vbat_crit);
 433         charger->thresholds.vbat_charge_start =
 434                 da9030_millivolt_to_reg(pdata->vbat_charge_start);
 435         charger->thresholds.vbat_charge_stop =
 436                 da9030_millivolt_to_reg(pdata->vbat_charge_stop);
 437         charger->thresholds.vbat_charge_restart =
 438                 da9030_millivolt_to_reg(pdata->vbat_charge_restart);
 439
 440         charger->thresholds.vcharge_min =
 441                 da9030_millivolt_to_reg(pdata->vcharge_min);
 442         charger->thresholds.vcharge_max =
 443                 da9030_millivolt_to_reg(pdata->vcharge_max);
 444 }
 445
 446 static void da9030_battery_setup_psy(struct da9030_charger *charger)
 447 {
 448         struct power_supply *psy = &charger->psy;
 449         struct power_supply_info *info = charger->battery_info;
 450
 451         psy->name = info->name;
 452         psy->use_for_apm = info->use_for_apm;
 453         psy->type = POWER_SUPPLY_TYPE_BATTERY;
 454         psy->get_property = da9030_battery_get_property;
 455
 456         psy->properties = da9030_battery_props;
 457         psy->num_properties = ARRAY_SIZE(da9030_battery_props);
 458 };
 459
 460 static int da9030_battery_charger_init(struct da9030_charger *charger)
 461 {
 462         char v[5];
 463         int ret;
 464
 465         v[0] = v[1] = charger->thresholds.vbat_low;
 466         v[2] = charger->thresholds.tbat_high;
 467         v[3] = charger->thresholds.tbat_restart;
 468         v[4] = charger->thresholds.tbat_low;
 469
 470         ret = da903x_writes(charger->master, DA9030_VBATMON, 5, v);
 471         if (ret)
 472                 return ret;
 473
 474         /*
 475          * Enable reference voltage supply for ADC from the LDO_INTERNAL
 476          * regulator. Must be set before ADC measurements can be made.
 477          */
 478         ret = da903x_write(charger->master, DA9030_ADC_MAN_CONTROL,
 479                            DA9030_ADC_LDO_INT_ENABLE |
 480                            DA9030_ADC_TBATREF_ENABLE);
 481         if (ret)
 482                 return ret;
 483
 484         /* enable auto ADC measuremnts */
 485         return da903x_write(charger->master, DA9030_ADC_AUTO_CONTROL,
 486                             DA9030_ADC_TBAT_ENABLE | DA9030_ADC_VBAT_IN_TXON |
 487                             DA9030_ADC_VCH_ENABLE | DA9030_ADC_ICH_ENABLE |
 488                             DA9030_ADC_VBAT_ENABLE |
 489                             DA9030_ADC_AUTO_SLEEP_ENABLE);
 490 }
 491
 492 static int da9030_battery_probe(struct platform_device *pdev)
 493 {
 494         struct da9030_charger *charger;
 495         struct da9030_battery_info *pdata = pdev->dev.platform_data;
 496         int ret;
 497
 498         if (pdata == NULL)
 499                 return -EINVAL;
 500
 501         if (pdata->charge_milliamp >= 1500 ||
 502             pdata->charge_millivolt < 4000 ||
 503             pdata->charge_millivolt > 4350)
 504                 return -EINVAL;
 505
 506         charger = kzalloc(sizeof(*charger), GFP_KERNEL);
 507         if (charger == NULL)
 508                 return -ENOMEM;
 509
 510         charger->master = pdev->dev.parent;
 511
 512         /* 10 seconds between monotor runs unless platfrom defines other
 513            interval */
 514         charger->interval = msecs_to_jiffies(
 515                 (pdata->batmon_interval ? : 10) * 1000);
 516
 517         charger->charge_milliamp = pdata->charge_milliamp;
 518         charger->charge_millivolt = pdata->charge_millivolt;
 519         charger->battery_info = pdata->battery_info;
 520         charger->battery_low = pdata->battery_low;
 521         charger->battery_critical = pdata->battery_critical;
 522
 523         da9030_battery_convert_thresholds(charger, pdata);
 524
 525         ret = da9030_battery_charger_init(charger);
 526         if (ret)
 527                 goto err_charger_init;
 528
 529         INIT_DELAYED_WORK(&charger->work, da9030_charging_monitor);
 530         schedule_delayed_work(&charger->work, charger->interval);
 531
 532         charger->nb.notifier_call = da9030_battery_event;
 533         ret = da903x_register_notifier(charger->master, &charger->nb,
 534                                        DA9030_EVENT_CHDET |
 535                                        DA9030_EVENT_VBATMON |
 536                                        DA9030_EVENT_CHIOVER |
 537                                        DA9030_EVENT_TBAT);
 538         if (ret)
 539                 goto err_notifier;
 540
 541         da9030_battery_setup_psy(charger);
 542         ret = power_supply_register(&pdev->dev, &charger->psy);
 543         if (ret)
 544                 goto err_ps_register;
 545
 546         charger->debug_file = da9030_bat_create_debugfs(charger);
 547         platform_set_drvdata(pdev, charger);
 548         return 0;
 549
 550 err_ps_register:
 551         da903x_unregister_notifier(charger->master, &charger->nb,
 552                                    DA9030_EVENT_CHDET | DA9030_EVENT_VBATMON |
 553                                    DA9030_EVENT_CHIOVER | DA9030_EVENT_TBAT);
 554 err_notifier:
 555         cancel_delayed_work(&charger->work);
 556
 557 err_charger_init:
 558         kfree(charger);
 559
 560         return ret;
 561 }
 562
 563 static int da9030_battery_remove(struct platform_device *dev)
 564 {
 565         struct da9030_charger *charger = platform_get_drvdata(dev);
 566
 567         da9030_bat_remove_debugfs(charger);
 568
 569         da903x_unregister_notifier(charger->master, &charger->nb,
 570                                    DA9030_EVENT_CHDET | DA9030_EVENT_VBATMON |
 571                                    DA9030_EVENT_CHIOVER | DA9030_EVENT_TBAT);
 572         cancel_delayed_work_sync(&charger->work);
 573         da9030_set_charge(charger, 0);
 574         power_supply_unregister(&charger->psy);
 575
 576         kfree(charger);
 577
 578         return 0;
 579 }
 580
 581 static struct platform_driver da903x_battery_driver = {
 582         .driver = {
 583                 .name   = "da903x-battery",
 584                 .owner  = THIS_MODULE,
 585         },
 586         .probe = da9030_battery_probe,
 587         .remove = da9030_battery_remove,
 588 };
 589
 590 static int da903x_battery_init(void)
 591 {
 592         return platform_driver_register(&da903x_battery_driver);
 593 }
 594
 595 static void da903x_battery_exit(void)
 596 {
 597         platform_driver_unregister(&da903x_battery_driver);
 598 }
 599
 600 module_init(da903x_battery_init);
 601 module_exit(da903x_battery_exit);
 602
 603 MODULE_DESCRIPTION("DA9030 battery charger driver");
 604 MODULE_AUTHOR("Mike Rapoport, CompuLab");
 605 MODULE_LICENSE("GPL");