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/gpio.h>
  26 #include <linux/mfd/core.h>
  27 #include <linux/power_supply.h>
  28
  29 #include <linux/power/jz4740-battery.h>
  30 #include <linux/jz4740-adc.h>
  31
  32 struct jz_battery {
  33         struct jz_battery_platform_data *pdata;
  34         struct platform_device *pdev;
  35
  36         struct resource *mem;
  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         unsigned 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
 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         cancel_delayed_work(&jz_battery->work);
 177         schedule_delayed_work(&jz_battery->work, 0);
 178 }
 179
 180 static irqreturn_t jz_battery_charge_irq(int irq, void *data)
 181 {
 182         struct jz_battery *jz_battery = data;
 183
 184         cancel_delayed_work(&jz_battery->work);
 185         schedule_delayed_work(&jz_battery->work, 0);
 186
 187         return IRQ_HANDLED;
 188 }
 189
 190 static void jz_battery_update(struct jz_battery *jz_battery)
 191 {
 192         int status;
 193         long voltage;
 194         bool has_changed = false;
 195         int is_charging;
 196
 197         if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 198                 is_charging = gpio_get_value(jz_battery->pdata->gpio_charge);
 199                 is_charging ^= jz_battery->pdata->gpio_charge_active_low;
 200                 if (is_charging)
 201                         status = POWER_SUPPLY_STATUS_CHARGING;
 202                 else
 203                         status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 204
 205                 if (status != jz_battery->status) {
 206                         jz_battery->status = status;
 207                         has_changed = true;
 208                 }
 209         }
 210
 211         voltage = jz_battery_read_voltage(jz_battery);
 212         if (abs(voltage - jz_battery->voltage) < 50000) {
 213                 jz_battery->voltage = voltage;
 214                 has_changed = true;
 215         }
 216
 217         if (has_changed)
 218                 power_supply_changed(&jz_battery->battery);
 219 }
 220
 221 static enum power_supply_property jz_battery_properties[] = {
 222         POWER_SUPPLY_PROP_STATUS,
 223         POWER_SUPPLY_PROP_TECHNOLOGY,
 224         POWER_SUPPLY_PROP_HEALTH,
 225         POWER_SUPPLY_PROP_CAPACITY,
 226         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 227         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
 228         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 229         POWER_SUPPLY_PROP_PRESENT,
 230 };
 231
 232 static void jz_battery_work(struct work_struct *work)
 233 {
 234         /* Too small interval will increase system workload */
 235         const int interval = HZ * 30;
 236         struct jz_battery *jz_battery = container_of(work, struct jz_battery,
 237                                             work.work);
 238
 239         jz_battery_update(jz_battery);
 240         schedule_delayed_work(&jz_battery->work, interval);
 241 }
 242
 243 static int __devinit jz_battery_probe(struct platform_device *pdev)
 244 {
 245         int ret = 0;
 246         struct jz_battery_platform_data *pdata = pdev->dev.parent->platform_data;
 247         struct jz_battery *jz_battery;
 248         struct power_supply *battery;
 249
 250         if (!pdata) {
 251                 dev_err(&pdev->dev, "No platform_data supplied\n");
 252                 return -ENXIO;
 253         }
 254
 255         jz_battery = kzalloc(sizeof(*jz_battery), GFP_KERNEL);
 256         if (!jz_battery) {
 257                 dev_err(&pdev->dev, "Failed to allocate driver structure\n");
 258                 return -ENOMEM;
 259         }
 260
 261         jz_battery->cell = mfd_get_cell(pdev);
 262
 263         jz_battery->irq = platform_get_irq(pdev, 0);
 264         if (jz_battery->irq < 0) {
 265                 ret = jz_battery->irq;
 266                 dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret);
 267                 goto err_free;
 268         }
 269
 270         jz_battery->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 271         if (!jz_battery->mem) {
 272                 ret = -ENOENT;
 273                 dev_err(&pdev->dev, "Failed to get platform mmio resource\n");
 274                 goto err_free;
 275         }
 276
 277         jz_battery->mem = request_mem_region(jz_battery->mem->start,
 278                                 resource_size(jz_battery->mem), pdev->name);
 279         if (!jz_battery->mem) {
 280                 ret = -EBUSY;
 281                 dev_err(&pdev->dev, "Failed to request mmio memory region\n");
 282                 goto err_free;
 283         }
 284
 285         jz_battery->base = ioremap_nocache(jz_battery->mem->start,
 286                                 resource_size(jz_battery->mem));
 287         if (!jz_battery->base) {
 288                 ret = -EBUSY;
 289                 dev_err(&pdev->dev, "Failed to ioremap mmio memory\n");
 290                 goto err_release_mem_region;
 291         }
 292
 293         battery = &jz_battery->battery;
 294         battery->name = pdata->info.name;
 295         battery->type = POWER_SUPPLY_TYPE_BATTERY;
 296         battery->properties     = jz_battery_properties;
 297         battery->num_properties = ARRAY_SIZE(jz_battery_properties);
 298         battery->get_property = jz_battery_get_property;
 299         battery->external_power_changed = jz_battery_external_power_changed;
 300         battery->use_for_apm = 1;
 301
 302         jz_battery->pdata = pdata;
 303         jz_battery->pdev = pdev;
 304
 305         init_completion(&jz_battery->read_completion);
 306         mutex_init(&jz_battery->lock);
 307
 308         INIT_DELAYED_WORK(&jz_battery->work, jz_battery_work);
 309
 310         ret = request_irq(jz_battery->irq, jz_battery_irq_handler, 0, pdev->name,
 311                         jz_battery);
 312         if (ret) {
 313                 dev_err(&pdev->dev, "Failed to request irq %d\n", ret);
 314                 goto err_iounmap;
 315         }
 316         disable_irq(jz_battery->irq);
 317
 318         if (gpio_is_valid(pdata->gpio_charge)) {
 319                 ret = gpio_request(pdata->gpio_charge, dev_name(&pdev->dev));
 320                 if (ret) {
 321                         dev_err(&pdev->dev, "charger state gpio request failed.\n");
 322                         goto err_free_irq;
 323                 }
 324                 ret = gpio_direction_input(pdata->gpio_charge);
 325                 if (ret) {
 326                         dev_err(&pdev->dev, "charger state gpio set direction failed.\n");
 327                         goto err_free_gpio;
 328                 }
 329
 330                 jz_battery->charge_irq = gpio_to_irq(pdata->gpio_charge);
 331
 332                 if (jz_battery->charge_irq >= 0) {
 333                         ret = request_irq(jz_battery->charge_irq,
 334                                     jz_battery_charge_irq,
 335                                     IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 336                                     dev_name(&pdev->dev), jz_battery);
 337                         if (ret) {
 338                                 dev_err(&pdev->dev, "Failed to request charge irq: %d\n", ret);
 339                                 goto err_free_gpio;
 340                         }
 341                 }
 342         } else {
 343                 jz_battery->charge_irq = -1;
 344         }
 345
 346         if (jz_battery->pdata->info.voltage_max_design <= 2500000)
 347                 jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB,
 348                         JZ_ADC_CONFIG_BAT_MB);
 349         else
 350                 jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB, 0);
 351
 352         ret = power_supply_register(&pdev->dev, &jz_battery->battery);
 353         if (ret) {
 354                 dev_err(&pdev->dev, "power supply battery register failed.\n");
 355                 goto err_free_charge_irq;
 356         }
 357
 358         platform_set_drvdata(pdev, jz_battery);
 359         schedule_delayed_work(&jz_battery->work, 0);
 360
 361         return 0;
 362
 363 err_free_charge_irq:
 364         if (jz_battery->charge_irq >= 0)
 365                 free_irq(jz_battery->charge_irq, jz_battery);
 366 err_free_gpio:
 367         if (gpio_is_valid(pdata->gpio_charge))
 368                 gpio_free(jz_battery->pdata->gpio_charge);
 369 err_free_irq:
 370         free_irq(jz_battery->irq, jz_battery);
 371 err_iounmap:
 372         platform_set_drvdata(pdev, NULL);
 373         iounmap(jz_battery->base);
 374 err_release_mem_region:
 375         release_mem_region(jz_battery->mem->start, resource_size(jz_battery->mem));
 376 err_free:
 377         kfree(jz_battery);
 378         return ret;
 379 }
 380
 381 static int __devexit jz_battery_remove(struct platform_device *pdev)
 382 {
 383         struct jz_battery *jz_battery = platform_get_drvdata(pdev);
 384
 385         cancel_delayed_work_sync(&jz_battery->work);
 386
 387         if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 388                 if (jz_battery->charge_irq >= 0)
 389                         free_irq(jz_battery->charge_irq, jz_battery);
 390                 gpio_free(jz_battery->pdata->gpio_charge);
 391         }
 392
 393         power_supply_unregister(&jz_battery->battery);
 394
 395         free_irq(jz_battery->irq, jz_battery);
 396
 397         iounmap(jz_battery->base);
 398         release_mem_region(jz_battery->mem->start, resource_size(jz_battery->mem));
 399         kfree(jz_battery);
 400
 401         return 0;
 402 }
 403
 404 #ifdef CONFIG_PM
 405 static int jz_battery_suspend(struct device *dev)
 406 {
 407         struct jz_battery *jz_battery = dev_get_drvdata(dev);
 408
 409         cancel_delayed_work_sync(&jz_battery->work);
 410         jz_battery->status = POWER_SUPPLY_STATUS_UNKNOWN;
 411
 412         return 0;
 413 }
 414
 415 static int jz_battery_resume(struct device *dev)
 416 {
 417         struct jz_battery *jz_battery = dev_get_drvdata(dev);
 418
 419         schedule_delayed_work(&jz_battery->work, 0);
 420
 421         return 0;
 422 }
 423
 424 static const struct dev_pm_ops jz_battery_pm_ops = {
 425         .suspend        = jz_battery_suspend,
 426         .resume         = jz_battery_resume,
 427 };
 428
 429 #define JZ_BATTERY_PM_OPS (&jz_battery_pm_ops)
 430 #else
 431 #define JZ_BATTERY_PM_OPS NULL
 432 #endif
 433
 434 static struct platform_driver jz_battery_driver = {
 435         .probe          = jz_battery_probe,
 436         .remove         = __devexit_p(jz_battery_remove),
 437         .driver = {
 438                 .name = "jz4740-battery",
 439                 .owner = THIS_MODULE,
 440                 .pm = JZ_BATTERY_PM_OPS,
 441         },
 442 };
 443
 444 static int __init jz_battery_init(void)
 445 {
 446         return platform_driver_register(&jz_battery_driver);
 447 }
 448 module_init(jz_battery_init);
 449
 450 static void __exit jz_battery_exit(void)
 451 {
 452         platform_driver_unregister(&jz_battery_driver);
 453 }
 454 module_exit(jz_battery_exit);
 455
 456 MODULE_ALIAS("platform:jz4740-battery");
 457 MODULE_LICENSE("GPL");
 458 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 459 MODULE_DESCRIPTION("JZ4740 SoC battery driver");