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
  23 #include <linux/delay.h>
  24 #include <linux/gpio.h>
  25 #include <linux/mfd/core.h>
  26 #include <linux/power_supply.h>
  27
  28 #include <linux/power/jz4740-battery.h>
  29 #include <linux/jz4740-adc.h>
  30
  31 struct jz_battery {
  32         struct jz_battery_platform_data *pdata;
  33         struct platform_device *pdev;
  34
  35         struct resource *mem;
  36         void __iomem *base;
  37
  38         int irq;
  39         int charge_irq;
  40
  41         struct mfd_cell *cell;
  42
  43         int status;
  44         long voltage;
  45
  46         struct completion read_completion;
  47
  48         struct power_supply battery;
  49         struct delayed_work work;
  50
  51         struct mutex lock;
  52 };
  53
  54 static inline struct jz_battery *psy_to_jz_battery(struct power_supply *psy)
  55 {
  56         return container_of(psy, struct jz_battery, battery);
  57 }
  58
  59 static irqreturn_t jz_battery_irq_handler(int irq, void *devid)
  60 {
  61         struct jz_battery *battery = devid;
  62
  63         complete(&battery->read_completion);
  64         return IRQ_HANDLED;
  65 }
  66
  67 static long jz_battery_read_voltage(struct jz_battery *battery)
  68 {
  69         unsigned long t;
  70         unsigned long val;
  71         long voltage;
  72
  73         mutex_lock(&battery->lock);
  74
  75         INIT_COMPLETION(battery->read_completion);
  76
  77         enable_irq(battery->irq);
  78         battery->cell->enable(battery->pdev);
  79
  80         t = wait_for_completion_interruptible_timeout(&battery->read_completion,
  81                 HZ);
  82
  83         if (t > 0) {
  84                 val = readw(battery->base) & 0xfff;
  85
  86                 if (battery->pdata->info.voltage_max_design <= 2500000)
  87                         val = (val * 78125UL) >> 7UL;
  88                 else
  89                         val = ((val * 924375UL) >> 9UL) + 33000;
  90                 voltage = (long)val;
  91         } else {
  92                 voltage = t ? t : -ETIMEDOUT;
  93         }
  94
  95         battery->cell->disable(battery->pdev);
  96         disable_irq(battery->irq);
  97
  98         mutex_unlock(&battery->lock);
  99
 100         return voltage;
 101 }
 102
 103 static int jz_battery_get_capacity(struct power_supply *psy)
 104 {
 105         struct jz_battery *jz_battery = psy_to_jz_battery(psy);
 106         struct power_supply_info *info = &jz_battery->pdata->info;
 107         long voltage;
 108         int ret;
 109         int voltage_span;
 110
 111         voltage = jz_battery_read_voltage(jz_battery);
 112
 113         if (voltage < 0)
 114                 return voltage;
 115
 116         voltage_span = info->voltage_max_design - info->voltage_min_design;
 117         ret = ((voltage - info->voltage_min_design) * 100) / voltage_span;
 118
 119         if (ret > 100)
 120                 ret = 100;
 121         else if (ret < 0)
 122                 ret = 0;
 123
 124         return ret;
 125 }
 126
 127 static int jz_battery_get_property(struct power_supply *psy,
 128         enum power_supply_property psp, union power_supply_propval *val)
 129 {
 130         struct jz_battery *jz_battery = psy_to_jz_battery(psy);
 131         struct power_supply_info *info = &jz_battery->pdata->info;
 132         long voltage;
 133
 134         switch (psp) {
 135         case POWER_SUPPLY_PROP_STATUS:
 136                 val->intval = jz_battery->status;
 137                 break;
 138         case POWER_SUPPLY_PROP_TECHNOLOGY:
 139                 val->intval = jz_battery->pdata->info.technology;
 140                 break;
 141         case POWER_SUPPLY_PROP_HEALTH:
 142                 voltage = jz_battery_read_voltage(jz_battery);
 143                 if (voltage < info->voltage_min_design)
 144                         val->intval = POWER_SUPPLY_HEALTH_DEAD;
 145                 else
 146                         val->intval = POWER_SUPPLY_HEALTH_GOOD;
 147                 break;
 148         case POWER_SUPPLY_PROP_CAPACITY:
 149                 val->intval = jz_battery_get_capacity(psy);
 150                 break;
 151         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 152                 val->intval = jz_battery_read_voltage(jz_battery);
 153                 if (val->intval < 0)
 154                         return val->intval;
 155                 break;
 156         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 157                 val->intval = info->voltage_max_design;
 158                 break;
 159         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 160                 val->intval = info->voltage_min_design;
 161                 break;
 162         case POWER_SUPPLY_PROP_PRESENT:
 163                 val->intval = 1;
 164                 break;
 165         default:
 166                 return -EINVAL;
 167         }
 168         return 0;
 169 }
 170
 171 static void jz_battery_external_power_changed(struct power_supply *psy)
 172 {
 173         struct jz_battery *jz_battery = psy_to_jz_battery(psy);
 174
 175         cancel_delayed_work(&jz_battery->work);
 176         schedule_delayed_work(&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         cancel_delayed_work(&jz_battery->work);
 184         schedule_delayed_work(&jz_battery->work, 0);
 185
 186         return IRQ_HANDLED;
 187 }
 188
 189 static 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 (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
 220 static 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
 231 static 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
 242 static int __devinit 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 jz_battery *jz_battery;
 247         struct power_supply *battery;
 248
 249         jz_battery = kzalloc(sizeof(*jz_battery), GFP_KERNEL);
 250         if (!jz_battery) {
 251                 dev_err(&pdev->dev, "Failed to allocate driver structure\n");
 252                 return -ENOMEM;
 253         }
 254
 255         jz_battery->cell = pdev->dev.platform_data;
 256
 257         jz_battery->irq = platform_get_irq(pdev, 0);
 258         if (jz_battery->irq < 0) {
 259                 ret = jz_battery->irq;
 260                 dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret);
 261                 goto err_free;
 262         }
 263
 264         jz_battery->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 265         if (!jz_battery->mem) {
 266                 ret = -ENOENT;
 267                 dev_err(&pdev->dev, "Failed to get platform mmio resource\n");
 268                 goto err_free;
 269         }
 270
 271         jz_battery->mem = request_mem_region(jz_battery->mem->start,
 272                                 resource_size(jz_battery->mem), pdev->name);
 273         if (!jz_battery->mem) {
 274                 ret = -EBUSY;
 275                 dev_err(&pdev->dev, "Failed to request mmio memory region\n");
 276                 goto err_free;
 277         }
 278
 279         jz_battery->base = ioremap_nocache(jz_battery->mem->start,
 280                                 resource_size(jz_battery->mem));
 281         if (!jz_battery->base) {
 282                 ret = -EBUSY;
 283                 dev_err(&pdev->dev, "Failed to ioremap mmio memory\n");
 284                 goto err_release_mem_region;
 285         }
 286
 287         battery = &jz_battery->battery;
 288         battery->name = pdata->info.name;
 289         battery->type = POWER_SUPPLY_TYPE_BATTERY;
 290         battery->properties     = jz_battery_properties;
 291         battery->num_properties = ARRAY_SIZE(jz_battery_properties);
 292         battery->get_property = jz_battery_get_property;
 293         battery->external_power_changed = jz_battery_external_power_changed;
 294         battery->use_for_apm = 1;
 295
 296         jz_battery->pdata = pdata;
 297         jz_battery->pdev = pdev;
 298
 299         init_completion(&jz_battery->read_completion);
 300         mutex_init(&jz_battery->lock);
 301
 302         INIT_DELAYED_WORK(&jz_battery->work, jz_battery_work);
 303
 304         ret = request_irq(jz_battery->irq, jz_battery_irq_handler, 0, pdev->name,
 305                         jz_battery);
 306         if (ret) {
 307                 dev_err(&pdev->dev, "Failed to request irq %d\n", ret);
 308                 goto err_iounmap;
 309         }
 310         disable_irq(jz_battery->irq);
 311
 312         if (gpio_is_valid(pdata->gpio_charge)) {
 313                 ret = gpio_request(pdata->gpio_charge, dev_name(&pdev->dev));
 314                 if (ret) {
 315                         dev_err(&pdev->dev, "charger state gpio request failed.\n");
 316                         goto err_free_irq;
 317                 }
 318                 ret = gpio_direction_input(pdata->gpio_charge);
 319                 if (ret) {
 320                         dev_err(&pdev->dev, "charger state gpio set direction failed.\n");
 321                         goto err_free_gpio;
 322                 }
 323
 324                 jz_battery->charge_irq = gpio_to_irq(pdata->gpio_charge);
 325
 326                 if (jz_battery->charge_irq >= 0) {
 327                         ret = request_irq(jz_battery->charge_irq,
 328                                     jz_battery_charge_irq,
 329                                     IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 330                                     dev_name(&pdev->dev), jz_battery);
 331                         if (ret) {
 332                                 dev_err(&pdev->dev, "Failed to request charge irq: %d\n", ret);
 333                                 goto err_free_gpio;
 334                         }
 335                 }
 336         } else {
 337                 jz_battery->charge_irq = -1;
 338         }
 339
 340         if (jz_battery->pdata->info.voltage_max_design <= 2500000)
 341                 jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB,
 342                         JZ_ADC_CONFIG_BAT_MB);
 343         else
 344                 jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB, 0);
 345
 346         ret = power_supply_register(&pdev->dev, &jz_battery->battery);
 347         if (ret) {
 348                 dev_err(&pdev->dev, "power supply battery register failed.\n");
 349                 goto err_free_charge_irq;
 350         }
 351
 352         platform_set_drvdata(pdev, jz_battery);
 353         schedule_delayed_work(&jz_battery->work, 0);
 354
 355         return 0;
 356
 357 err_free_charge_irq:
 358         if (jz_battery->charge_irq >= 0)
 359                 free_irq(jz_battery->charge_irq, jz_battery);
 360 err_free_gpio:
 361         if (gpio_is_valid(pdata->gpio_charge))
 362                 gpio_free(jz_battery->pdata->gpio_charge);
 363 err_free_irq:
 364         free_irq(jz_battery->irq, jz_battery);
 365 err_iounmap:
 366         platform_set_drvdata(pdev, NULL);
 367         iounmap(jz_battery->base);
 368 err_release_mem_region:
 369         release_mem_region(jz_battery->mem->start, resource_size(jz_battery->mem));
 370 err_free:
 371         kfree(jz_battery);
 372         return ret;
 373 }
 374
 375 static int __devexit jz_battery_remove(struct platform_device *pdev)
 376 {
 377         struct jz_battery *jz_battery = platform_get_drvdata(pdev);
 378
 379         cancel_delayed_work_sync(&jz_battery->work);
 380
 381         if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 382                 if (jz_battery->charge_irq >= 0)
 383                         free_irq(jz_battery->charge_irq, jz_battery);
 384                 gpio_free(jz_battery->pdata->gpio_charge);
 385         }
 386
 387         power_supply_unregister(&jz_battery->battery);
 388
 389         free_irq(jz_battery->irq, jz_battery);
 390
 391         iounmap(jz_battery->base);
 392         release_mem_region(jz_battery->mem->start, resource_size(jz_battery->mem));
 393
 394         return 0;
 395 }
 396
 397 #ifdef CONFIG_PM
 398 static int jz_battery_suspend(struct device *dev)
 399 {
 400         struct jz_battery *jz_battery = dev_get_drvdata(dev);
 401
 402         cancel_delayed_work_sync(&jz_battery->work);
 403         jz_battery->status = POWER_SUPPLY_STATUS_UNKNOWN;
 404
 405         return 0;
 406 }
 407
 408 static int jz_battery_resume(struct device *dev)
 409 {
 410         struct jz_battery *jz_battery = dev_get_drvdata(dev);
 411
 412         schedule_delayed_work(&jz_battery->work, 0);
 413
 414         return 0;
 415 }
 416
 417 static const struct dev_pm_ops jz_battery_pm_ops = {
 418         .suspend        = jz_battery_suspend,
 419         .resume         = jz_battery_resume,
 420 };
 421
 422 #define JZ_BATTERY_PM_OPS (&jz_battery_pm_ops)
 423 #else
 424 #define JZ_BATTERY_PM_OPS NULL
 425 #endif
 426
 427 static struct platform_driver jz_battery_driver = {
 428         .probe          = jz_battery_probe,
 429         .remove         = __devexit_p(jz_battery_remove),
 430         .driver = {
 431                 .name = "jz4740-battery",
 432                 .owner = THIS_MODULE,
 433                 .pm = JZ_BATTERY_PM_OPS,
 434         },
 435 };
 436
 437 static int __init jz_battery_init(void)
 438 {
 439         return platform_driver_register(&jz_battery_driver);
 440 }
 441 module_init(jz_battery_init);
 442
 443 static void __exit jz_battery_exit(void)
 444 {
 445         platform_driver_unregister(&jz_battery_driver);
 446 }
 447 module_exit(jz_battery_exit);
 448
 449 MODULE_ALIAS("platform:jz4740-battery");
 450 MODULE_LICENSE("GPL");
 451 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 452 MODULE_DESCRIPTION("JZ4740 SoC battery driver");