linux/drivers/power/supply/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/err.h>
  26#include <linux/gpio.h>
  27#include <linux/mfd/core.h>
  28#include <linux/power_supply.h>
  29
  30#include <linux/power/jz4740-battery.h>
  31#include <linux/jz4740-adc.h>
  32
  33struct jz_battery {
  34        struct jz_battery_platform_data *pdata;
  35        struct platform_device *pdev;
  36
  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 power_supply_desc battery_desc;
  51        struct delayed_work work;
  52
  53        struct mutex lock;
  54};
  55
  56static inline struct jz_battery *psy_to_jz_battery(struct power_supply *psy)
  57{
  58        return power_supply_get_drvdata(psy);
  59}
  60
  61static irqreturn_t jz_battery_irq_handler(int irq, void *devid)
  62{
  63        struct jz_battery *battery = devid;
  64
  65        complete(&battery->read_completion);
  66        return IRQ_HANDLED;
  67}
  68
  69static long jz_battery_read_voltage(struct jz_battery *battery)
  70{
  71        long t;
  72        unsigned long val;
  73        long voltage;
  74
  75        mutex_lock(&battery->lock);
  76
  77        reinit_completion(&battery->read_completion);
  78
  79        enable_irq(battery->irq);
  80        battery->cell->enable(battery->pdev);
  81
  82        t = wait_for_completion_interruptible_timeout(&battery->read_completion,
  83                HZ);
  84
  85        if (t > 0) {
  86                val = readw(battery->base) & 0xfff;
  87
  88                if (battery->pdata->info.voltage_max_design <= 2500000)
  89                        val = (val * 78125UL) >> 7UL;
  90                else
  91                        val = ((val * 924375UL) >> 9UL) + 33000;
  92                voltage = (long)val;
  93        } else {
  94                voltage = t ? t : -ETIMEDOUT;
  95        }
  96
  97        battery->cell->disable(battery->pdev);
  98        disable_irq(battery->irq);
  99
 100        mutex_unlock(&battery->lock);
 101
 102        return voltage;
 103}
 104
 105static int jz_battery_get_capacity(struct power_supply *psy)
 106{
 107        struct jz_battery *jz_battery = psy_to_jz_battery(psy);
 108        struct power_supply_info *info = &jz_battery->pdata->info;
 109        long voltage;
 110        int ret;
 111        int voltage_span;
 112
 113        voltage = jz_battery_read_voltage(jz_battery);
 114
 115        if (voltage < 0)
 116                return voltage;
 117
 118        voltage_span = info->voltage_max_design - info->voltage_min_design;
 119        ret = ((voltage - info->voltage_min_design) * 100) / voltage_span;
 120
 121        if (ret > 100)
 122                ret = 100;
 123        else if (ret < 0)
 124                ret = 0;
 125
 126        return ret;
 127}
 128
 129static int jz_battery_get_property(struct power_supply *psy,
 130        enum power_supply_property psp, union power_supply_propval *val)
 131{
 132        struct jz_battery *jz_battery = psy_to_jz_battery(psy);
 133        struct power_supply_info *info = &jz_battery->pdata->info;
 134        long voltage;
 135
 136        switch (psp) {
 137        case POWER_SUPPLY_PROP_STATUS:
 138                val->intval = jz_battery->status;
 139                break;
 140        case POWER_SUPPLY_PROP_TECHNOLOGY:
 141                val->intval = jz_battery->pdata->info.technology;
 142                break;
 143        case POWER_SUPPLY_PROP_HEALTH:
 144                voltage = jz_battery_read_voltage(jz_battery);
 145                if (voltage < info->voltage_min_design)
 146                        val->intval = POWER_SUPPLY_HEALTH_DEAD;
 147                else
 148                        val->intval = POWER_SUPPLY_HEALTH_GOOD;
 149                break;
 150        case POWER_SUPPLY_PROP_CAPACITY:
 151                val->intval = jz_battery_get_capacity(psy);
 152                break;
 153        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 154                val->intval = jz_battery_read_voltage(jz_battery);
 155                if (val->intval < 0)
 156                        return val->intval;
 157                break;
 158        case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 159                val->intval = info->voltage_max_design;
 160                break;
 161        case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 162                val->intval = info->voltage_min_design;
 163                break;
 164        case POWER_SUPPLY_PROP_PRESENT:
 165                val->intval = 1;
 166                break;
 167        default:
 168                return -EINVAL;
 169        }
 170        return 0;
 171}
 172
 173static void jz_battery_external_power_changed(struct power_supply *psy)
 174{
 175        struct jz_battery *jz_battery = psy_to_jz_battery(psy);
 176
 177        mod_delayed_work(system_wq, &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        mod_delayed_work(system_wq, &jz_battery->work, 0);
 185
 186        return IRQ_HANDLED;
 187}
 188
 189static void jz_battery_update(struct jz_battery *jz_battery)
 190{
 191        int status;
 192        long voltage;
 193        bool has_changed = false;
 194        int is_charging;
 195
 196        if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 197                is_charging = gpio_get_value(jz_battery->pdata->gpio_charge);
 198                is_charging ^= jz_battery->pdata->gpio_charge_active_low;
 199                if (is_charging)
 200                        status = POWER_SUPPLY_STATUS_CHARGING;
 201                else
 202                        status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 203
 204                if (status != jz_battery->status) {
 205                        jz_battery->status = status;
 206                        has_changed = true;
 207                }
 208        }
 209
 210        voltage = jz_battery_read_voltage(jz_battery);
 211        if (voltage >= 0 && abs(voltage - jz_battery->voltage) > 50000) {
 212                jz_battery->voltage = voltage;
 213                has_changed = true;
 214        }
 215
 216        if (has_changed)
 217                power_supply_changed(jz_battery->battery);
 218}
 219
 220static enum power_supply_property jz_battery_properties[] = {
 221        POWER_SUPPLY_PROP_STATUS,
 222        POWER_SUPPLY_PROP_TECHNOLOGY,
 223        POWER_SUPPLY_PROP_HEALTH,
 224        POWER_SUPPLY_PROP_CAPACITY,
 225        POWER_SUPPLY_PROP_VOLTAGE_NOW,
 226        POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
 227        POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 228        POWER_SUPPLY_PROP_PRESENT,
 229};
 230
 231static void jz_battery_work(struct work_struct *work)
 232{
 233        /* Too small interval will increase system workload */
 234        const int interval = HZ * 30;
 235        struct jz_battery *jz_battery = container_of(work, struct jz_battery,
 236                                            work.work);
 237
 238        jz_battery_update(jz_battery);
 239        schedule_delayed_work(&jz_battery->work, interval);
 240}
 241
 242static int jz_battery_probe(struct platform_device *pdev)
 243{
 244        int ret = 0;
 245        struct jz_battery_platform_data *pdata = pdev->dev.parent->platform_data;
 246        struct power_supply_config psy_cfg = {};
 247        struct jz_battery *jz_battery;
 248        struct power_supply_desc *battery_desc;
 249        struct resource *mem;
 250
 251        if (!pdata) {
 252                dev_err(&pdev->dev, "No platform_data supplied\n");
 253                return -ENXIO;
 254        }
 255
 256        jz_battery = devm_kzalloc(&pdev->dev, sizeof(*jz_battery), GFP_KERNEL);
 257        if (!jz_battery) {
 258                dev_err(&pdev->dev, "Failed to allocate driver structure\n");
 259                return -ENOMEM;
 260        }
 261
 262        jz_battery->cell = mfd_get_cell(pdev);
 263
 264        jz_battery->irq = platform_get_irq(pdev, 0);
 265        if (jz_battery->irq < 0) {
 266                dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret);
 267                return jz_battery->irq;
 268        }
 269
 270        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 271
 272        jz_battery->base = devm_ioremap_resource(&pdev->dev, mem);
 273        if (IS_ERR(jz_battery->base))
 274                return PTR_ERR(jz_battery->base);
 275
 276        battery_desc = &jz_battery->battery_desc;
 277        battery_desc->name = pdata->info.name;
 278        battery_desc->type = POWER_SUPPLY_TYPE_BATTERY;
 279        battery_desc->properties        = jz_battery_properties;
 280        battery_desc->num_properties    = ARRAY_SIZE(jz_battery_properties);
 281        battery_desc->get_property      = jz_battery_get_property;
 282        battery_desc->external_power_changed =
 283                                        jz_battery_external_power_changed;
 284        battery_desc->use_for_apm       = 1;
 285
 286        psy_cfg.drv_data = jz_battery;
 287
 288        jz_battery->pdata = pdata;
 289        jz_battery->pdev = pdev;
 290
 291        init_completion(&jz_battery->read_completion);
 292        mutex_init(&jz_battery->lock);
 293
 294        INIT_DELAYED_WORK(&jz_battery->work, jz_battery_work);
 295
 296        ret = request_irq(jz_battery->irq, jz_battery_irq_handler, 0, pdev->name,
 297                        jz_battery);
 298        if (ret) {
 299                dev_err(&pdev->dev, "Failed to request irq %d\n", ret);
 300                return ret;
 301        }
 302        disable_irq(jz_battery->irq);
 303
 304        if (gpio_is_valid(pdata->gpio_charge)) {
 305                ret = gpio_request(pdata->gpio_charge, dev_name(&pdev->dev));
 306                if (ret) {
 307                        dev_err(&pdev->dev, "charger state gpio request failed.\n");
 308                        goto err_free_irq;
 309                }
 310                ret = gpio_direction_input(pdata->gpio_charge);
 311                if (ret) {
 312                        dev_err(&pdev->dev, "charger state gpio set direction failed.\n");
 313                        goto err_free_gpio;
 314                }
 315
 316                jz_battery->charge_irq = gpio_to_irq(pdata->gpio_charge);
 317
 318                if (jz_battery->charge_irq >= 0) {
 319                        ret = request_irq(jz_battery->charge_irq,
 320                                    jz_battery_charge_irq,
 321                                    IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 322                                    dev_name(&pdev->dev), jz_battery);
 323                        if (ret) {
 324                                dev_err(&pdev->dev, "Failed to request charge irq: %d\n", ret);
 325                                goto err_free_gpio;
 326                        }
 327                }
 328        } else {
 329                jz_battery->charge_irq = -1;
 330        }
 331
 332        if (jz_battery->pdata->info.voltage_max_design <= 2500000)
 333                jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB,
 334                        JZ_ADC_CONFIG_BAT_MB);
 335        else
 336                jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB, 0);
 337
 338        jz_battery->battery = power_supply_register(&pdev->dev, battery_desc,
 339                                                        &psy_cfg);
 340        if (IS_ERR(jz_battery->battery)) {
 341                dev_err(&pdev->dev, "power supply battery register failed.\n");
 342                ret = PTR_ERR(jz_battery->battery);
 343                goto err_free_charge_irq;
 344        }
 345
 346        platform_set_drvdata(pdev, jz_battery);
 347        schedule_delayed_work(&jz_battery->work, 0);
 348
 349        return 0;
 350
 351err_free_charge_irq:
 352        if (jz_battery->charge_irq >= 0)
 353                free_irq(jz_battery->charge_irq, jz_battery);
 354err_free_gpio:
 355        if (gpio_is_valid(pdata->gpio_charge))
 356                gpio_free(jz_battery->pdata->gpio_charge);
 357err_free_irq:
 358        free_irq(jz_battery->irq, jz_battery);
 359        return ret;
 360}
 361
 362static int jz_battery_remove(struct platform_device *pdev)
 363{
 364        struct jz_battery *jz_battery = platform_get_drvdata(pdev);
 365
 366        cancel_delayed_work_sync(&jz_battery->work);
 367
 368        if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 369                if (jz_battery->charge_irq >= 0)
 370                        free_irq(jz_battery->charge_irq, jz_battery);
 371                gpio_free(jz_battery->pdata->gpio_charge);
 372        }
 373
 374        power_supply_unregister(jz_battery->battery);
 375
 376        free_irq(jz_battery->irq, jz_battery);
 377
 378        return 0;
 379}
 380
 381#ifdef CONFIG_PM
 382static int jz_battery_suspend(struct device *dev)
 383{
 384        struct jz_battery *jz_battery = dev_get_drvdata(dev);
 385
 386        cancel_delayed_work_sync(&jz_battery->work);
 387        jz_battery->status = POWER_SUPPLY_STATUS_UNKNOWN;
 388
 389        return 0;
 390}
 391
 392static int jz_battery_resume(struct device *dev)
 393{
 394        struct jz_battery *jz_battery = dev_get_drvdata(dev);
 395
 396        schedule_delayed_work(&jz_battery->work, 0);
 397
 398        return 0;
 399}
 400
 401static const struct dev_pm_ops jz_battery_pm_ops = {
 402        .suspend        = jz_battery_suspend,
 403        .resume         = jz_battery_resume,
 404};
 405
 406#define JZ_BATTERY_PM_OPS (&jz_battery_pm_ops)
 407#else
 408#define JZ_BATTERY_PM_OPS NULL
 409#endif
 410
 411static struct platform_driver jz_battery_driver = {
 412        .probe          = jz_battery_probe,
 413        .remove         = jz_battery_remove,
 414        .driver = {
 415                .name = "jz4740-battery",
 416                .pm = JZ_BATTERY_PM_OPS,
 417        },
 418};
 419
 420module_platform_driver(jz_battery_driver);
 421
 422MODULE_ALIAS("platform:jz4740-battery");
 423MODULE_LICENSE("GPL");
 424MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 425MODULE_DESCRIPTION("JZ4740 SoC battery driver");
 426