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