linux/drivers/power/da9030_battery.c
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   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
  60struct 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
  74struct 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
  89struct 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
 121static inline int da9030_reg_to_mV(int reg)
 122{
 123        return ((reg * 2650) >> 8) + 2650;
 124}
 125
 126static inline int da9030_millivolt_to_reg(int mV)
 127{
 128        return ((mV - 2650) << 8) / 2650;
 129}
 130
 131static inline int da9030_reg_to_mA(int reg)
 132{
 133        return ((reg * 24000) >> 8) / 15;
 134}
 135
 136#ifdef CONFIG_DEBUG_FS
 137static 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
 175static int debug_open(struct inode *inode, struct file *file)
 176{
 177        return single_open(file, bat_debug_show, inode->i_private);
 178}
 179
 180static 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
 187static 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
 194static void da9030_bat_remove_debugfs(struct da9030_charger *charger)
 195{
 196        debugfs_remove(charger->debug_file);
 197}
 198#else
 199static inline struct dentry *da9030_bat_create_debugfs(struct da9030_charger *charger)
 200{
 201        return NULL;
 202}
 203static inline void da9030_bat_remove_debugfs(struct da9030_charger *charger)
 204{
 205}
 206#endif
 207
 208static 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
 215static 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
 230static 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
 249static 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
 291static 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
 303static 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
 314static 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
 327static 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
 338static 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
 378static 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
 399static 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
 422static 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
 446static 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
 460static 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
 492static 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
 550err_ps_register:
 551        da903x_unregister_notifier(charger->master, &charger->nb,
 552                                   DA9030_EVENT_CHDET | DA9030_EVENT_VBATMON |
 553                                   DA9030_EVENT_CHIOVER | DA9030_EVENT_TBAT);
 554err_notifier:
 555        cancel_delayed_work(&charger->work);
 556
 557err_charger_init:
 558        kfree(charger);
 559
 560        return ret;
 561}
 562
 563static 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
 581static 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
 590static int da903x_battery_init(void)
 591{
 592        return platform_driver_register(&da903x_battery_driver);
 593}
 594
 595static void da903x_battery_exit(void)
 596{
 597        platform_driver_unregister(&da903x_battery_driver);
 598}
 599
 600module_init(da903x_battery_init);
 601module_exit(da903x_battery_exit);
 602
 603MODULE_DESCRIPTION("DA9030 battery charger driver");
 604MODULE_AUTHOR("Mike Rapoport, CompuLab");
 605MODULE_LICENSE("GPL");
 606