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