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         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         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
 248         if (!pdata) {
 249                 dev_err(&pdev->dev, "No platform_data supplied\n");
 250                 return -ENXIO;
 251         }
 252
 253         jz_battery = kzalloc(sizeof(*jz_battery), GFP_KERNEL);
 254         if (!jz_battery) {
 255                 dev_err(&pdev->dev, "Failed to allocate driver structure\n");
 256                 return -ENOMEM;
 257         }
 258
 259         jz_battery->cell = mfd_get_cell(pdev);
 260
 261         jz_battery->irq = platform_get_irq(pdev, 0);
 262         if (jz_battery->irq < 0) {
 263                 ret = jz_battery->irq;
 264                 dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret);
 265                 goto err_free;
 266         }
 267
 268         jz_battery->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 269         if (!jz_battery->mem) {
 270                 ret = -ENOENT;
 271                 dev_err(&pdev->dev, "Failed to get platform mmio resource\n");
 272                 goto err_free;
 273         }
 274
 275         jz_battery->mem = request_mem_region(jz_battery->mem->start,
 276                                 resource_size(jz_battery->mem), pdev->name);
 277         if (!jz_battery->mem) {
 278                 ret = -EBUSY;
 279                 dev_err(&pdev->dev, "Failed to request mmio memory region\n");
 280                 goto err_free;
 281         }
 282
 283         jz_battery->base = ioremap_nocache(jz_battery->mem->start,
 284                                 resource_size(jz_battery->mem));
 285         if (!jz_battery->base) {
 286                 ret = -EBUSY;
 287                 dev_err(&pdev->dev, "Failed to ioremap mmio memory\n");
 288                 goto err_release_mem_region;
 289         }
 290
 291         battery = &jz_battery->battery;
 292         battery->name = pdata->info.name;
 293         battery->type = POWER_SUPPLY_TYPE_BATTERY;
 294         battery->properties     = jz_battery_properties;
 295         battery->num_properties = ARRAY_SIZE(jz_battery_properties);
 296         battery->get_property = jz_battery_get_property;
 297         battery->external_power_changed = jz_battery_external_power_changed;
 298         battery->use_for_apm = 1;
 299
 300         jz_battery->pdata = pdata;
 301         jz_battery->pdev = pdev;
 302
 303         init_completion(&jz_battery->read_completion);
 304         mutex_init(&jz_battery->lock);
 305
 306         INIT_DELAYED_WORK(&jz_battery->work, jz_battery_work);
 307
 308         ret = request_irq(jz_battery->irq, jz_battery_irq_handler, 0, pdev->name,
 309                         jz_battery);
 310         if (ret) {
 311                 dev_err(&pdev->dev, "Failed to request irq %d\n", ret);
 312                 goto err_iounmap;
 313         }
 314         disable_irq(jz_battery->irq);
 315
 316         if (gpio_is_valid(pdata->gpio_charge)) {
 317                 ret = gpio_request(pdata->gpio_charge, dev_name(&pdev->dev));
 318                 if (ret) {
 319                         dev_err(&pdev->dev, "charger state gpio request failed.\n");
 320                         goto err_free_irq;
 321                 }
 322                 ret = gpio_direction_input(pdata->gpio_charge);
 323                 if (ret) {
 324                         dev_err(&pdev->dev, "charger state gpio set direction failed.\n");
 325                         goto err_free_gpio;
 326                 }
 327
 328                 jz_battery->charge_irq = gpio_to_irq(pdata->gpio_charge);
 329
 330                 if (jz_battery->charge_irq >= 0) {
 331                         ret = request_irq(jz_battery->charge_irq,
 332                                     jz_battery_charge_irq,
 333                                     IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 334                                     dev_name(&pdev->dev), jz_battery);
 335                         if (ret) {
 336                                 dev_err(&pdev->dev, "Failed to request charge irq: %d\n", ret);
 337                                 goto err_free_gpio;
 338                         }
 339                 }
 340         } else {
 341                 jz_battery->charge_irq = -1;
 342         }
 343
 344         if (jz_battery->pdata->info.voltage_max_design <= 2500000)
 345                 jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB,
 346                         JZ_ADC_CONFIG_BAT_MB);
 347         else
 348                 jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB, 0);
 349
 350         ret = power_supply_register(&pdev->dev, &jz_battery->battery);
 351         if (ret) {
 352                 dev_err(&pdev->dev, "power supply battery register failed.\n");
 353                 goto err_free_charge_irq;
 354         }
 355
 356         platform_set_drvdata(pdev, jz_battery);
 357         schedule_delayed_work(&jz_battery->work, 0);
 358
 359         return 0;
 360
 361 err_free_charge_irq:
 362         if (jz_battery->charge_irq >= 0)
 363                 free_irq(jz_battery->charge_irq, jz_battery);
 364 err_free_gpio:
 365         if (gpio_is_valid(pdata->gpio_charge))
 366                 gpio_free(jz_battery->pdata->gpio_charge);
 367 err_free_irq:
 368         free_irq(jz_battery->irq, jz_battery);
 369 err_iounmap:
 370         platform_set_drvdata(pdev, NULL);
 371         iounmap(jz_battery->base);
 372 err_release_mem_region:
 373         release_mem_region(jz_battery->mem->start, resource_size(jz_battery->mem));
 374 err_free:
 375         kfree(jz_battery);
 376         return ret;
 377 }
 378
 379 static int jz_battery_remove(struct platform_device *pdev)
 380 {
 381         struct jz_battery *jz_battery = platform_get_drvdata(pdev);
 382
 383         cancel_delayed_work_sync(&jz_battery->work);
 384
 385         if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 386                 if (jz_battery->charge_irq >= 0)
 387                         free_irq(jz_battery->charge_irq, jz_battery);
 388                 gpio_free(jz_battery->pdata->gpio_charge);
 389         }
 390
 391         power_supply_unregister(&jz_battery->battery);
 392
 393         free_irq(jz_battery->irq, jz_battery);
 394
 395         iounmap(jz_battery->base);
 396         release_mem_region(jz_battery->mem->start, resource_size(jz_battery->mem));
 397         kfree(jz_battery);
 398
 399         return 0;
 400 }
 401
 402 #ifdef CONFIG_PM
 403 static int jz_battery_suspend(struct device *dev)
 404 {
 405         struct jz_battery *jz_battery = dev_get_drvdata(dev);
 406
 407         cancel_delayed_work_sync(&jz_battery->work);
 408         jz_battery->status = POWER_SUPPLY_STATUS_UNKNOWN;
 409
 410         return 0;
 411 }
 412
 413 static int jz_battery_resume(struct device *dev)
 414 {
 415         struct jz_battery *jz_battery = dev_get_drvdata(dev);
 416
 417         schedule_delayed_work(&jz_battery->work, 0);
 418
 419         return 0;
 420 }
 421
 422 static const struct dev_pm_ops jz_battery_pm_ops = {
 423         .suspend        = jz_battery_suspend,
 424         .resume         = jz_battery_resume,
 425 };
 426
 427 #define JZ_BATTERY_PM_OPS (&jz_battery_pm_ops)
 428 #else
 429 #define JZ_BATTERY_PM_OPS NULL
 430 #endif
 431
 432 static struct platform_driver jz_battery_driver = {
 433         .probe          = jz_battery_probe,
 434         .remove         = jz_battery_remove,
 435         .driver = {
 436                 .name = "jz4740-battery",
 437                 .owner = THIS_MODULE,
 438                 .pm = JZ_BATTERY_PM_OPS,
 439         },
 440 };
 441
 442 module_platform_driver(jz_battery_driver);
 443
 444 MODULE_ALIAS("platform:jz4740-battery");
 445 MODULE_LICENSE("GPL");
 446 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 447 MODULE_DESCRIPTION("JZ4740 SoC battery driver");