drivers/power/jz4740-battery.c

   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
  33 struct 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
  55 static inline struct jz_battery *psy_to_jz_battery(struct power_supply *psy)
  56 {
  57         return container_of(psy, struct jz_battery, battery);
  58 }
  59
  60 static 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
  68 static 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         reinit_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
 104 static 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
 128 static 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
 172 static 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
 179 static 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
 188 static 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
 219 static 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
 230 static 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
 241 static 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
 344 err_free_charge_irq:
 345         if (jz_battery->charge_irq >= 0)
 346                 free_irq(jz_battery->charge_irq, jz_battery);
 347 err_free_gpio:
 348         if (gpio_is_valid(pdata->gpio_charge))
 349                 gpio_free(jz_battery->pdata->gpio_charge);
 350 err_free_irq:
 351         free_irq(jz_battery->irq, jz_battery);
 352         return ret;
 353 }
 354
 355 static 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
 375 static 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
 385 static 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
 394 static 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
 404 static 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
 414 module_platform_driver(jz_battery_driver);
 415
 416 MODULE_ALIAS("platform:jz4740-battery");
 417 MODULE_LICENSE("GPL");
 418 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 419 MODULE_DESCRIPTION("JZ4740 SoC battery driver");