linux/drivers/power/jz4740-battery.c
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   1/*
   2 * Battery measurement code for Ingenic JZ SOC.
   3 *
   4 * Copyright (C) 2009 Jiejing Zhang <kzjeef@gmail.com>
   5 * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
   6 *
   7 * based on tosa_battery.c
   8 *
   9 * Copyright (C) 2008 Marek Vasut <marek.vasut@gmail.com>
  10*
  11 * This program is free software; you can redistribute it and/or modify
  12 * it under the terms of the GNU General Public License version 2 as
  13 * published by the Free Software Foundation.
  14 *
  15 */
  16
  17#include <linux/interrupt.h>
  18#include <linux/kernel.h>
  19#include <linux/module.h>
  20#include <linux/platform_device.h>
  21#include <linux/slab.h>
  22#include <linux/io.h>
  23
  24#include <linux/delay.h>
  25#include <linux/gpio.h>
  26#include <linux/mfd/core.h>
  27#include <linux/power_supply.h>
  28
  29#include <linux/power/jz4740-battery.h>
  30#include <linux/jz4740-adc.h>
  31
  32struct jz_battery {
  33        struct jz_battery_platform_data *pdata;
  34        struct platform_device *pdev;
  35
  36        struct resource *mem;
  37        void __iomem *base;
  38
  39        int irq;
  40        int charge_irq;
  41
  42        const struct mfd_cell *cell;
  43
  44        int status;
  45        long voltage;
  46
  47        struct completion read_completion;
  48
  49        struct power_supply battery;
  50        struct delayed_work work;
  51
  52        struct mutex lock;
  53};
  54
  55static inline struct jz_battery *psy_to_jz_battery(struct power_supply *psy)
  56{
  57        return container_of(psy, struct jz_battery, battery);
  58}
  59
  60static irqreturn_t jz_battery_irq_handler(int irq, void *devid)
  61{
  62        struct jz_battery *battery = devid;
  63
  64        complete(&battery->read_completion);
  65        return IRQ_HANDLED;
  66}
  67
  68static long jz_battery_read_voltage(struct jz_battery *battery)
  69{
  70        long t;
  71        unsigned long val;
  72        long voltage;
  73
  74        mutex_lock(&battery->lock);
  75
  76        INIT_COMPLETION(battery->read_completion);
  77
  78        enable_irq(battery->irq);
  79        battery->cell->enable(battery->pdev);
  80
  81        t = wait_for_completion_interruptible_timeout(&battery->read_completion,
  82                HZ);
  83
  84        if (t > 0) {
  85                val = readw(battery->base) & 0xfff;
  86
  87                if (battery->pdata->info.voltage_max_design <= 2500000)
  88                        val = (val * 78125UL) >> 7UL;
  89                else
  90                        val = ((val * 924375UL) >> 9UL) + 33000;
  91                voltage = (long)val;
  92        } else {
  93                voltage = t ? t : -ETIMEDOUT;
  94        }
  95
  96        battery->cell->disable(battery->pdev);
  97        disable_irq(battery->irq);
  98
  99        mutex_unlock(&battery->lock);
 100
 101        return voltage;
 102}
 103
 104static int jz_battery_get_capacity(struct power_supply *psy)
 105{
 106        struct jz_battery *jz_battery = psy_to_jz_battery(psy);
 107        struct power_supply_info *info = &jz_battery->pdata->info;
 108        long voltage;
 109        int ret;
 110        int voltage_span;
 111
 112        voltage = jz_battery_read_voltage(jz_battery);
 113
 114        if (voltage < 0)
 115                return voltage;
 116
 117        voltage_span = info->voltage_max_design - info->voltage_min_design;
 118        ret = ((voltage - info->voltage_min_design) * 100) / voltage_span;
 119
 120        if (ret > 100)
 121                ret = 100;
 122        else if (ret < 0)
 123                ret = 0;
 124
 125        return ret;
 126}
 127
 128static int jz_battery_get_property(struct power_supply *psy,
 129        enum power_supply_property psp, union power_supply_propval *val)
 130{
 131        struct jz_battery *jz_battery = psy_to_jz_battery(psy);
 132        struct power_supply_info *info = &jz_battery->pdata->info;
 133        long voltage;
 134
 135        switch (psp) {
 136        case POWER_SUPPLY_PROP_STATUS:
 137                val->intval = jz_battery->status;
 138                break;
 139        case POWER_SUPPLY_PROP_TECHNOLOGY:
 140                val->intval = jz_battery->pdata->info.technology;
 141                break;
 142        case POWER_SUPPLY_PROP_HEALTH:
 143                voltage = jz_battery_read_voltage(jz_battery);
 144                if (voltage < info->voltage_min_design)
 145                        val->intval = POWER_SUPPLY_HEALTH_DEAD;
 146                else
 147                        val->intval = POWER_SUPPLY_HEALTH_GOOD;
 148                break;
 149        case POWER_SUPPLY_PROP_CAPACITY:
 150                val->intval = jz_battery_get_capacity(psy);
 151                break;
 152        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 153                val->intval = jz_battery_read_voltage(jz_battery);
 154                if (val->intval < 0)
 155                        return val->intval;
 156                break;
 157        case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 158                val->intval = info->voltage_max_design;
 159                break;
 160        case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 161                val->intval = info->voltage_min_design;
 162                break;
 163        case POWER_SUPPLY_PROP_PRESENT:
 164                val->intval = 1;
 165                break;
 166        default:
 167                return -EINVAL;
 168        }
 169        return 0;
 170}
 171
 172static void jz_battery_external_power_changed(struct power_supply *psy)
 173{
 174        struct jz_battery *jz_battery = psy_to_jz_battery(psy);
 175
 176        cancel_delayed_work(&jz_battery->work);
 177        schedule_delayed_work(&jz_battery->work, 0);
 178}
 179
 180static irqreturn_t jz_battery_charge_irq(int irq, void *data)
 181{
 182        struct jz_battery *jz_battery = data;
 183
 184        cancel_delayed_work(&jz_battery->work);
 185        schedule_delayed_work(&jz_battery->work, 0);
 186
 187        return IRQ_HANDLED;
 188}
 189
 190static void jz_battery_update(struct jz_battery *jz_battery)
 191{
 192        int status;
 193        long voltage;
 194        bool has_changed = false;
 195        int is_charging;
 196
 197        if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 198                is_charging = gpio_get_value(jz_battery->pdata->gpio_charge);
 199                is_charging ^= jz_battery->pdata->gpio_charge_active_low;
 200                if (is_charging)
 201                        status = POWER_SUPPLY_STATUS_CHARGING;
 202                else
 203                        status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 204
 205                if (status != jz_battery->status) {
 206                        jz_battery->status = status;
 207                        has_changed = true;
 208                }
 209        }
 210
 211        voltage = jz_battery_read_voltage(jz_battery);
 212        if (abs(voltage - jz_battery->voltage) < 50000) {
 213                jz_battery->voltage = voltage;
 214                has_changed = true;
 215        }
 216
 217        if (has_changed)
 218                power_supply_changed(&jz_battery->battery);
 219}
 220
 221static enum power_supply_property jz_battery_properties[] = {
 222        POWER_SUPPLY_PROP_STATUS,
 223        POWER_SUPPLY_PROP_TECHNOLOGY,
 224        POWER_SUPPLY_PROP_HEALTH,
 225        POWER_SUPPLY_PROP_CAPACITY,
 226        POWER_SUPPLY_PROP_VOLTAGE_NOW,
 227        POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
 228        POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 229        POWER_SUPPLY_PROP_PRESENT,
 230};
 231
 232static void jz_battery_work(struct work_struct *work)
 233{
 234        /* Too small interval will increase system workload */
 235        const int interval = HZ * 30;
 236        struct jz_battery *jz_battery = container_of(work, struct jz_battery,
 237                                            work.work);
 238
 239        jz_battery_update(jz_battery);
 240        schedule_delayed_work(&jz_battery->work, interval);
 241}
 242
 243static int __devinit jz_battery_probe(struct platform_device *pdev)
 244{
 245        int ret = 0;
 246        struct jz_battery_platform_data *pdata = pdev->dev.parent->platform_data;
 247        struct jz_battery *jz_battery;
 248        struct power_supply *battery;
 249
 250        if (!pdata) {
 251                dev_err(&pdev->dev, "No platform_data supplied\n");
 252                return -ENXIO;
 253        }
 254
 255        jz_battery = kzalloc(sizeof(*jz_battery), GFP_KERNEL);
 256        if (!jz_battery) {
 257                dev_err(&pdev->dev, "Failed to allocate driver structure\n");
 258                return -ENOMEM;
 259        }
 260
 261        jz_battery->cell = mfd_get_cell(pdev);
 262
 263        jz_battery->irq = platform_get_irq(pdev, 0);
 264        if (jz_battery->irq < 0) {
 265                ret = jz_battery->irq;
 266                dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret);
 267                goto err_free;
 268        }
 269
 270        jz_battery->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 271        if (!jz_battery->mem) {
 272                ret = -ENOENT;
 273                dev_err(&pdev->dev, "Failed to get platform mmio resource\n");
 274                goto err_free;
 275        }
 276
 277        jz_battery->mem = request_mem_region(jz_battery->mem->start,
 278                                resource_size(jz_battery->mem), pdev->name);
 279        if (!jz_battery->mem) {
 280                ret = -EBUSY;
 281                dev_err(&pdev->dev, "Failed to request mmio memory region\n");
 282                goto err_free;
 283        }
 284
 285        jz_battery->base = ioremap_nocache(jz_battery->mem->start,
 286                                resource_size(jz_battery->mem));
 287        if (!jz_battery->base) {
 288                ret = -EBUSY;
 289                dev_err(&pdev->dev, "Failed to ioremap mmio memory\n");
 290                goto err_release_mem_region;
 291        }
 292
 293        battery = &jz_battery->battery;
 294        battery->name = pdata->info.name;
 295        battery->type = POWER_SUPPLY_TYPE_BATTERY;
 296        battery->properties     = jz_battery_properties;
 297        battery->num_properties = ARRAY_SIZE(jz_battery_properties);
 298        battery->get_property = jz_battery_get_property;
 299        battery->external_power_changed = jz_battery_external_power_changed;
 300        battery->use_for_apm = 1;
 301
 302        jz_battery->pdata = pdata;
 303        jz_battery->pdev = pdev;
 304
 305        init_completion(&jz_battery->read_completion);
 306        mutex_init(&jz_battery->lock);
 307
 308        INIT_DELAYED_WORK(&jz_battery->work, jz_battery_work);
 309
 310        ret = request_irq(jz_battery->irq, jz_battery_irq_handler, 0, pdev->name,
 311                        jz_battery);
 312        if (ret) {
 313                dev_err(&pdev->dev, "Failed to request irq %d\n", ret);
 314                goto err_iounmap;
 315        }
 316        disable_irq(jz_battery->irq);
 317
 318        if (gpio_is_valid(pdata->gpio_charge)) {
 319                ret = gpio_request(pdata->gpio_charge, dev_name(&pdev->dev));
 320                if (ret) {
 321                        dev_err(&pdev->dev, "charger state gpio request failed.\n");
 322                        goto err_free_irq;
 323                }
 324                ret = gpio_direction_input(pdata->gpio_charge);
 325                if (ret) {
 326                        dev_err(&pdev->dev, "charger state gpio set direction failed.\n");
 327                        goto err_free_gpio;
 328                }
 329
 330                jz_battery->charge_irq = gpio_to_irq(pdata->gpio_charge);
 331
 332                if (jz_battery->charge_irq >= 0) {
 333                        ret = request_irq(jz_battery->charge_irq,
 334                                    jz_battery_charge_irq,
 335                                    IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 336                                    dev_name(&pdev->dev), jz_battery);
 337                        if (ret) {
 338                                dev_err(&pdev->dev, "Failed to request charge irq: %d\n", ret);
 339                                goto err_free_gpio;
 340                        }
 341                }
 342        } else {
 343                jz_battery->charge_irq = -1;
 344        }
 345
 346        if (jz_battery->pdata->info.voltage_max_design <= 2500000)
 347                jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB,
 348                        JZ_ADC_CONFIG_BAT_MB);
 349        else
 350                jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB, 0);
 351
 352        ret = power_supply_register(&pdev->dev, &jz_battery->battery);
 353        if (ret) {
 354                dev_err(&pdev->dev, "power supply battery register failed.\n");
 355                goto err_free_charge_irq;
 356        }
 357
 358        platform_set_drvdata(pdev, jz_battery);
 359        schedule_delayed_work(&jz_battery->work, 0);
 360
 361        return 0;
 362
 363err_free_charge_irq:
 364        if (jz_battery->charge_irq >= 0)
 365                free_irq(jz_battery->charge_irq, jz_battery);
 366err_free_gpio:
 367        if (gpio_is_valid(pdata->gpio_charge))
 368                gpio_free(jz_battery->pdata->gpio_charge);
 369err_free_irq:
 370        free_irq(jz_battery->irq, jz_battery);
 371err_iounmap:
 372        platform_set_drvdata(pdev, NULL);
 373        iounmap(jz_battery->base);
 374err_release_mem_region:
 375        release_mem_region(jz_battery->mem->start, resource_size(jz_battery->mem));
 376err_free:
 377        kfree(jz_battery);
 378        return ret;
 379}
 380
 381static int __devexit jz_battery_remove(struct platform_device *pdev)
 382{
 383        struct jz_battery *jz_battery = platform_get_drvdata(pdev);
 384
 385        cancel_delayed_work_sync(&jz_battery->work);
 386
 387        if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 388                if (jz_battery->charge_irq >= 0)
 389                        free_irq(jz_battery->charge_irq, jz_battery);
 390                gpio_free(jz_battery->pdata->gpio_charge);
 391        }
 392
 393        power_supply_unregister(&jz_battery->battery);
 394
 395        free_irq(jz_battery->irq, jz_battery);
 396
 397        iounmap(jz_battery->base);
 398        release_mem_region(jz_battery->mem->start, resource_size(jz_battery->mem));
 399        kfree(jz_battery);
 400
 401        return 0;
 402}
 403
 404#ifdef CONFIG_PM
 405static int jz_battery_suspend(struct device *dev)
 406{
 407        struct jz_battery *jz_battery = dev_get_drvdata(dev);
 408
 409        cancel_delayed_work_sync(&jz_battery->work);
 410        jz_battery->status = POWER_SUPPLY_STATUS_UNKNOWN;
 411
 412        return 0;
 413}
 414
 415static int jz_battery_resume(struct device *dev)
 416{
 417        struct jz_battery *jz_battery = dev_get_drvdata(dev);
 418
 419        schedule_delayed_work(&jz_battery->work, 0);
 420
 421        return 0;
 422}
 423
 424static const struct dev_pm_ops jz_battery_pm_ops = {
 425        .suspend        = jz_battery_suspend,
 426        .resume         = jz_battery_resume,
 427};
 428
 429#define JZ_BATTERY_PM_OPS (&jz_battery_pm_ops)
 430#else
 431#define JZ_BATTERY_PM_OPS NULL
 432#endif
 433
 434static struct platform_driver jz_battery_driver = {
 435        .probe          = jz_battery_probe,
 436        .remove         = __devexit_p(jz_battery_remove),
 437        .driver = {
 438                .name = "jz4740-battery",
 439                .owner = THIS_MODULE,
 440                .pm = JZ_BATTERY_PM_OPS,
 441        },
 442};
 443
 444module_platform_driver(jz_battery_driver);
 445
 446MODULE_ALIAS("platform:jz4740-battery");
 447MODULE_LICENSE("GPL");
 448MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 449MODULE_DESCRIPTION("JZ4740 SoC battery driver");
 450
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