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         void __iomem *base;
  37
  38         int irq;
  39         int charge_irq;
  40
  41         const 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         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         mod_delayed_work(system_wq, &jz_battery->work, 0);
 176 }
 177
 178 static irqreturn_t jz_battery_charge_irq(int irq, void *data)
 179 {
 180         struct jz_battery *jz_battery = data;
 181
 182         mod_delayed_work(system_wq, &jz_battery->work, 0);
 183
 184         return IRQ_HANDLED;
 185 }
 186
 187 static void jz_battery_update(struct jz_battery *jz_battery)
 188 {
 189         int status;
 190         long voltage;
 191         bool has_changed = false;
 192         int is_charging;
 193
 194         if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 195                 is_charging = gpio_get_value(jz_battery->pdata->gpio_charge);
 196                 is_charging ^= jz_battery->pdata->gpio_charge_active_low;
 197                 if (is_charging)
 198                         status = POWER_SUPPLY_STATUS_CHARGING;
 199                 else
 200                         status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 201
 202                 if (status != jz_battery->status) {
 203                         jz_battery->status = status;
 204                         has_changed = true;
 205                 }
 206         }
 207
 208         voltage = jz_battery_read_voltage(jz_battery);
 209         if (abs(voltage - jz_battery->voltage) < 50000) {
 210                 jz_battery->voltage = voltage;
 211                 has_changed = true;
 212         }
 213
 214         if (has_changed)
 215                 power_supply_changed(&jz_battery->battery);
 216 }
 217
 218 static enum power_supply_property jz_battery_properties[] = {
 219         POWER_SUPPLY_PROP_STATUS,
 220         POWER_SUPPLY_PROP_TECHNOLOGY,
 221         POWER_SUPPLY_PROP_HEALTH,
 222         POWER_SUPPLY_PROP_CAPACITY,
 223         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 224         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
 225         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 226         POWER_SUPPLY_PROP_PRESENT,
 227 };
 228
 229 static void jz_battery_work(struct work_struct *work)
 230 {
 231         /* Too small interval will increase system workload */
 232         const int interval = HZ * 30;
 233         struct jz_battery *jz_battery = container_of(work, struct jz_battery,
 234                                             work.work);
 235
 236         jz_battery_update(jz_battery);
 237         schedule_delayed_work(&jz_battery->work, interval);
 238 }
 239
 240 static int jz_battery_probe(struct platform_device *pdev)
 241 {
 242         int ret = 0;
 243         struct jz_battery_platform_data *pdata = pdev->dev.parent->platform_data;
 244         struct jz_battery *jz_battery;
 245         struct power_supply *battery;
 246         struct resource *mem;
 247
 248         if (!pdata) {
 249                 dev_err(&pdev->dev, "No platform_data supplied\n");
 250                 return -ENXIO;
 251         }
 252
 253         jz_battery = devm_kzalloc(&pdev->dev, 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                 dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret);
 264                 return jz_battery->irq;
 265         }
 266
 267         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 268
 269         jz_battery->base = devm_request_and_ioremap(&pdev->dev, mem);
 270         if (!jz_battery->base)
 271                 return -EBUSY;
 272
 273         battery = &jz_battery->battery;
 274         battery->name = pdata->info.name;
 275         battery->type = POWER_SUPPLY_TYPE_BATTERY;
 276         battery->properties     = jz_battery_properties;
 277         battery->num_properties = ARRAY_SIZE(jz_battery_properties);
 278         battery->get_property = jz_battery_get_property;
 279         battery->external_power_changed = jz_battery_external_power_changed;
 280         battery->use_for_apm = 1;
 281
 282         jz_battery->pdata = pdata;
 283         jz_battery->pdev = pdev;
 284
 285         init_completion(&jz_battery->read_completion);
 286         mutex_init(&jz_battery->lock);
 287
 288         INIT_DELAYED_WORK(&jz_battery->work, jz_battery_work);
 289
 290         ret = request_irq(jz_battery->irq, jz_battery_irq_handler, 0, pdev->name,
 291                         jz_battery);
 292         if (ret) {
 293                 dev_err(&pdev->dev, "Failed to request irq %d\n", ret);
 294                 goto err;
 295         }
 296         disable_irq(jz_battery->irq);
 297
 298         if (gpio_is_valid(pdata->gpio_charge)) {
 299                 ret = gpio_request(pdata->gpio_charge, dev_name(&pdev->dev));
 300                 if (ret) {
 301                         dev_err(&pdev->dev, "charger state gpio request failed.\n");
 302                         goto err_free_irq;
 303                 }
 304                 ret = gpio_direction_input(pdata->gpio_charge);
 305                 if (ret) {
 306                         dev_err(&pdev->dev, "charger state gpio set direction failed.\n");
 307                         goto err_free_gpio;
 308                 }
 309
 310                 jz_battery->charge_irq = gpio_to_irq(pdata->gpio_charge);
 311
 312                 if (jz_battery->charge_irq >= 0) {
 313                         ret = request_irq(jz_battery->charge_irq,
 314                                     jz_battery_charge_irq,
 315                                     IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 316                                     dev_name(&pdev->dev), jz_battery);
 317                         if (ret) {
 318                                 dev_err(&pdev->dev, "Failed to request charge irq: %d\n", ret);
 319                                 goto err_free_gpio;
 320                         }
 321                 }
 322         } else {
 323                 jz_battery->charge_irq = -1;
 324         }
 325
 326         if (jz_battery->pdata->info.voltage_max_design <= 2500000)
 327                 jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB,
 328                         JZ_ADC_CONFIG_BAT_MB);
 329         else
 330                 jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB, 0);
 331
 332         ret = power_supply_register(&pdev->dev, &jz_battery->battery);
 333         if (ret) {
 334                 dev_err(&pdev->dev, "power supply battery register failed.\n");
 335                 goto err_free_charge_irq;
 336         }
 337
 338         platform_set_drvdata(pdev, jz_battery);
 339         schedule_delayed_work(&jz_battery->work, 0);
 340
 341         return 0;
 342
 343 err_free_charge_irq:
 344         if (jz_battery->charge_irq >= 0)
 345                 free_irq(jz_battery->charge_irq, jz_battery);
 346 err_free_gpio:
 347         if (gpio_is_valid(pdata->gpio_charge))
 348                 gpio_free(jz_battery->pdata->gpio_charge);
 349 err_free_irq:
 350         free_irq(jz_battery->irq, jz_battery);
 351 err:
 352         platform_set_drvdata(pdev, NULL);
 353         return ret;
 354 }
 355
 356 static int jz_battery_remove(struct platform_device *pdev)
 357 {
 358         struct jz_battery *jz_battery = platform_get_drvdata(pdev);
 359
 360         cancel_delayed_work_sync(&jz_battery->work);
 361
 362         if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
 363                 if (jz_battery->charge_irq >= 0)
 364                         free_irq(jz_battery->charge_irq, jz_battery);
 365                 gpio_free(jz_battery->pdata->gpio_charge);
 366         }
 367
 368         power_supply_unregister(&jz_battery->battery);
 369
 370         free_irq(jz_battery->irq, jz_battery);
 371
 372         return 0;
 373 }
 374
 375 #ifdef CONFIG_PM
 376 static int jz_battery_suspend(struct device *dev)
 377 {
 378         struct jz_battery *jz_battery = dev_get_drvdata(dev);
 379
 380         cancel_delayed_work_sync(&jz_battery->work);
 381         jz_battery->status = POWER_SUPPLY_STATUS_UNKNOWN;
 382
 383         return 0;
 384 }
 385
 386 static int jz_battery_resume(struct device *dev)
 387 {
 388         struct jz_battery *jz_battery = dev_get_drvdata(dev);
 389
 390         schedule_delayed_work(&jz_battery->work, 0);
 391
 392         return 0;
 393 }
 394
 395 static const struct dev_pm_ops jz_battery_pm_ops = {
 396         .suspend        = jz_battery_suspend,
 397         .resume         = jz_battery_resume,
 398 };
 399
 400 #define JZ_BATTERY_PM_OPS (&jz_battery_pm_ops)
 401 #else
 402 #define JZ_BATTERY_PM_OPS NULL
 403 #endif
 404
 405 static struct platform_driver jz_battery_driver = {
 406         .probe          = jz_battery_probe,
 407         .remove         = jz_battery_remove,
 408         .driver = {
 409                 .name = "jz4740-battery",
 410                 .owner = THIS_MODULE,
 411                 .pm = JZ_BATTERY_PM_OPS,
 412         },
 413 };
 414
 415 module_platform_driver(jz_battery_driver);
 416
 417 MODULE_ALIAS("platform:jz4740-battery");
 418 MODULE_LICENSE("GPL");
 419 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 420 MODULE_DESCRIPTION("JZ4740 SoC battery driver");