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/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 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        mod_delayed_work(system_wq, &jz_battery->work, 0);
 177}
 178
 179static irqreturn_t jz_battery_charge_irq(int irq, void *data)
 180{
 181        struct jz_battery *jz_battery = data;
 182
 183        mod_delayed_work(system_wq, &jz_battery->work, 0);
 184
 185        return IRQ_HANDLED;
 186}
 187
 188static void jz_battery_update(struct jz_battery *jz_battery)
 189{
 190        int status;
 191        long voltage;
 192        bool has_changed = false;
 193        int is_charging;
 194
 195        if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 196                is_charging = gpio_get_value(jz_battery->pdata->gpio_charge);
 197                is_charging ^= jz_battery->pdata->gpio_charge_active_low;
 198                if (is_charging)
 199                        status = POWER_SUPPLY_STATUS_CHARGING;
 200                else
 201                        status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 202
 203                if (status != jz_battery->status) {
 204                        jz_battery->status = status;
 205                        has_changed = true;
 206                }
 207        }
 208
 209        voltage = jz_battery_read_voltage(jz_battery);
 210        if (abs(voltage - jz_battery->voltage) < 50000) {
 211                jz_battery->voltage = voltage;
 212                has_changed = true;
 213        }
 214
 215        if (has_changed)
 216                power_supply_changed(&jz_battery->battery);
 217}
 218
 219static enum power_supply_property jz_battery_properties[] = {
 220        POWER_SUPPLY_PROP_STATUS,
 221        POWER_SUPPLY_PROP_TECHNOLOGY,
 222        POWER_SUPPLY_PROP_HEALTH,
 223        POWER_SUPPLY_PROP_CAPACITY,
 224        POWER_SUPPLY_PROP_VOLTAGE_NOW,
 225        POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
 226        POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 227        POWER_SUPPLY_PROP_PRESENT,
 228};
 229
 230static void jz_battery_work(struct work_struct *work)
 231{
 232        /* Too small interval will increase system workload */
 233        const int interval = HZ * 30;
 234        struct jz_battery *jz_battery = container_of(work, struct jz_battery,
 235                                            work.work);
 236
 237        jz_battery_update(jz_battery);
 238        schedule_delayed_work(&jz_battery->work, interval);
 239}
 240
 241static int jz_battery_probe(struct platform_device *pdev)
 242{
 243        int ret = 0;
 244        struct jz_battery_platform_data *pdata = pdev->dev.parent->platform_data;
 245        struct jz_battery *jz_battery;
 246        struct power_supply *battery;
 247        struct resource *mem;
 248
 249        if (!pdata) {
 250                dev_err(&pdev->dev, "No platform_data supplied\n");
 251                return -ENXIO;
 252        }
 253
 254        jz_battery = devm_kzalloc(&pdev->dev, sizeof(*jz_battery), GFP_KERNEL);
 255        if (!jz_battery) {
 256                dev_err(&pdev->dev, "Failed to allocate driver structure\n");
 257                return -ENOMEM;
 258        }
 259
 260        jz_battery->cell = mfd_get_cell(pdev);
 261
 262        jz_battery->irq = platform_get_irq(pdev, 0);
 263        if (jz_battery->irq < 0) {
 264                dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret);
 265                return jz_battery->irq;
 266        }
 267
 268        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 269
 270        jz_battery->base = devm_ioremap_resource(&pdev->dev, mem);
 271        if (IS_ERR(jz_battery->base))
 272                return PTR_ERR(jz_battery->base);
 273
 274        battery = &jz_battery->battery;
 275        battery->name = pdata->info.name;
 276        battery->type = POWER_SUPPLY_TYPE_BATTERY;
 277        battery->properties     = jz_battery_properties;
 278        battery->num_properties = ARRAY_SIZE(jz_battery_properties);
 279        battery->get_property = jz_battery_get_property;
 280        battery->external_power_changed = jz_battery_external_power_changed;
 281        battery->use_for_apm = 1;
 282
 283        jz_battery->pdata = pdata;
 284        jz_battery->pdev = pdev;
 285
 286        init_completion(&jz_battery->read_completion);
 287        mutex_init(&jz_battery->lock);
 288
 289        INIT_DELAYED_WORK(&jz_battery->work, jz_battery_work);
 290
 291        ret = request_irq(jz_battery->irq, jz_battery_irq_handler, 0, pdev->name,
 292                        jz_battery);
 293        if (ret) {
 294                dev_err(&pdev->dev, "Failed to request irq %d\n", ret);
 295                return ret;
 296        }
 297        disable_irq(jz_battery->irq);
 298
 299        if (gpio_is_valid(pdata->gpio_charge)) {
 300                ret = gpio_request(pdata->gpio_charge, dev_name(&pdev->dev));
 301                if (ret) {
 302                        dev_err(&pdev->dev, "charger state gpio request failed.\n");
 303                        goto err_free_irq;
 304                }
 305                ret = gpio_direction_input(pdata->gpio_charge);
 306                if (ret) {
 307                        dev_err(&pdev->dev, "charger state gpio set direction failed.\n");
 308                        goto err_free_gpio;
 309                }
 310
 311                jz_battery->charge_irq = gpio_to_irq(pdata->gpio_charge);
 312
 313                if (jz_battery->charge_irq >= 0) {
 314                        ret = request_irq(jz_battery->charge_irq,
 315                                    jz_battery_charge_irq,
 316                                    IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 317                                    dev_name(&pdev->dev), jz_battery);
 318                        if (ret) {
 319                                dev_err(&pdev->dev, "Failed to request charge irq: %d\n", ret);
 320                                goto err_free_gpio;
 321                        }
 322                }
 323        } else {
 324                jz_battery->charge_irq = -1;
 325        }
 326
 327        if (jz_battery->pdata->info.voltage_max_design <= 2500000)
 328                jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB,
 329                        JZ_ADC_CONFIG_BAT_MB);
 330        else
 331                jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB, 0);
 332
 333        ret = power_supply_register(&pdev->dev, &jz_battery->battery);
 334        if (ret) {
 335                dev_err(&pdev->dev, "power supply battery register failed.\n");
 336                goto err_free_charge_irq;
 337        }
 338
 339        platform_set_drvdata(pdev, jz_battery);
 340        schedule_delayed_work(&jz_battery->work, 0);
 341
 342        return 0;
 343
 344err_free_charge_irq:
 345        if (jz_battery->charge_irq >= 0)
 346                free_irq(jz_battery->charge_irq, jz_battery);
 347err_free_gpio:
 348        if (gpio_is_valid(pdata->gpio_charge))
 349                gpio_free(jz_battery->pdata->gpio_charge);
 350err_free_irq:
 351        free_irq(jz_battery->irq, jz_battery);
 352        return ret;
 353}
 354
 355static int jz_battery_remove(struct platform_device *pdev)
 356{
 357        struct jz_battery *jz_battery = platform_get_drvdata(pdev);
 358
 359        cancel_delayed_work_sync(&jz_battery->work);
 360
 361        if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 362                if (jz_battery->charge_irq >= 0)
 363                        free_irq(jz_battery->charge_irq, jz_battery);
 364                gpio_free(jz_battery->pdata->gpio_charge);
 365        }
 366
 367        power_supply_unregister(&jz_battery->battery);
 368
 369        free_irq(jz_battery->irq, jz_battery);
 370
 371        return 0;
 372}
 373
 374#ifdef CONFIG_PM
 375static int jz_battery_suspend(struct device *dev)
 376{
 377        struct jz_battery *jz_battery = dev_get_drvdata(dev);
 378
 379        cancel_delayed_work_sync(&jz_battery->work);
 380        jz_battery->status = POWER_SUPPLY_STATUS_UNKNOWN;
 381
 382        return 0;
 383}
 384
 385static int jz_battery_resume(struct device *dev)
 386{
 387        struct jz_battery *jz_battery = dev_get_drvdata(dev);
 388
 389        schedule_delayed_work(&jz_battery->work, 0);
 390
 391        return 0;
 392}
 393
 394static const struct dev_pm_ops jz_battery_pm_ops = {
 395        .suspend        = jz_battery_suspend,
 396        .resume         = jz_battery_resume,
 397};
 398
 399#define JZ_BATTERY_PM_OPS (&jz_battery_pm_ops)
 400#else
 401#define JZ_BATTERY_PM_OPS NULL
 402#endif
 403
 404static struct platform_driver jz_battery_driver = {
 405        .probe          = jz_battery_probe,
 406        .remove         = jz_battery_remove,
 407        .driver = {
 408                .name = "jz4740-battery",
 409                .owner = THIS_MODULE,
 410                .pm = JZ_BATTERY_PM_OPS,
 411        },
 412};
 413
 414module_platform_driver(jz_battery_driver);
 415
 416MODULE_ALIAS("platform:jz4740-battery");
 417MODULE_LICENSE("GPL");
 418MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 419MODULE_DESCRIPTION("JZ4740 SoC battery driver");
 420
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