drivers/power/supply/generic-adc-battery.c

   1 /*
   2  * Generic battery driver code using IIO
   3  * Copyright (C) 2012, Anish Kumar <anish198519851985@gmail.com>
   4  * based on jz4740-battery.c
   5  * based on s3c_adc_battery.c
   6  *
   7  * This file is subject to the terms and conditions of the GNU General Public
   8  * License.  See the file COPYING in the main directory of this archive for
   9  * more details.
  10  *
  11  */
  12 #include <linux/interrupt.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/power_supply.h>
  15 #include <linux/gpio.h>
  16 #include <linux/err.h>
  17 #include <linux/timer.h>
  18 #include <linux/jiffies.h>
  19 #include <linux/errno.h>
  20 #include <linux/init.h>
  21 #include <linux/module.h>
  22 #include <linux/slab.h>
  23 #include <linux/iio/consumer.h>
  24 #include <linux/iio/types.h>
  25 #include <linux/power/generic-adc-battery.h>
  26
  27 #define JITTER_DEFAULT 10 /* hope 10ms is enough */
  28
  29 enum gab_chan_type {
  30         GAB_VOLTAGE = 0,
  31         GAB_CURRENT,
  32         GAB_POWER,
  33         GAB_MAX_CHAN_TYPE
  34 };
  35
  36 /*
  37  * gab_chan_name suggests the standard channel names for commonly used
  38  * channel types.
  39  */
  40 static const char *const gab_chan_name[] = {
  41         [GAB_VOLTAGE]   = "voltage",
  42         [GAB_CURRENT]   = "current",
  43         [GAB_POWER]             = "power",
  44 };
  45
  46 struct gab {
  47         struct power_supply             *psy;
  48         struct power_supply_desc        psy_desc;
  49         struct iio_channel      *channel[GAB_MAX_CHAN_TYPE];
  50         struct gab_platform_data        *pdata;
  51         struct delayed_work bat_work;
  52         int     level;
  53         int     status;
  54         bool cable_plugged;
  55 };
  56
  57 static struct gab *to_generic_bat(struct power_supply *psy)
  58 {
  59         return power_supply_get_drvdata(psy);
  60 }
  61
  62 static void gab_ext_power_changed(struct power_supply *psy)
  63 {
  64         struct gab *adc_bat = to_generic_bat(psy);
  65
  66         schedule_delayed_work(&adc_bat->bat_work, msecs_to_jiffies(0));
  67 }
  68
  69 static const enum power_supply_property gab_props[] = {
  70         POWER_SUPPLY_PROP_STATUS,
  71         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
  72         POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
  73         POWER_SUPPLY_PROP_CHARGE_NOW,
  74         POWER_SUPPLY_PROP_VOLTAGE_NOW,
  75         POWER_SUPPLY_PROP_CURRENT_NOW,
  76         POWER_SUPPLY_PROP_TECHNOLOGY,
  77         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
  78         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
  79         POWER_SUPPLY_PROP_MODEL_NAME,
  80 };
  81
  82 /*
  83  * This properties are set based on the received platform data and this
  84  * should correspond one-to-one with enum chan_type.
  85  */
  86 static const enum power_supply_property gab_dyn_props[] = {
  87         POWER_SUPPLY_PROP_VOLTAGE_NOW,
  88         POWER_SUPPLY_PROP_CURRENT_NOW,
  89         POWER_SUPPLY_PROP_POWER_NOW,
  90 };
  91
  92 static bool gab_charge_finished(struct gab *adc_bat)
  93 {
  94         struct gab_platform_data *pdata = adc_bat->pdata;
  95         bool ret = gpio_get_value(pdata->gpio_charge_finished);
  96         bool inv = pdata->gpio_inverted;
  97
  98         if (!gpio_is_valid(pdata->gpio_charge_finished))
  99                 return false;
 100         return ret ^ inv;
 101 }
 102
 103 static int gab_get_status(struct gab *adc_bat)
 104 {
 105         struct gab_platform_data *pdata = adc_bat->pdata;
 106         struct power_supply_info *bat_info;
 107
 108         bat_info = &pdata->battery_info;
 109         if (adc_bat->level == bat_info->charge_full_design)
 110                 return POWER_SUPPLY_STATUS_FULL;
 111         return adc_bat->status;
 112 }
 113
 114 static enum gab_chan_type gab_prop_to_chan(enum power_supply_property psp)
 115 {
 116         switch (psp) {
 117         case POWER_SUPPLY_PROP_POWER_NOW:
 118                 return GAB_POWER;
 119         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 120                 return GAB_VOLTAGE;
 121         case POWER_SUPPLY_PROP_CURRENT_NOW:
 122                 return GAB_CURRENT;
 123         default:
 124                 WARN_ON(1);
 125                 break;
 126         }
 127         return GAB_POWER;
 128 }
 129
 130 static int read_channel(struct gab *adc_bat, enum power_supply_property psp,
 131                 int *result)
 132 {
 133         int ret;
 134         int chan_index;
 135
 136         chan_index = gab_prop_to_chan(psp);
 137         ret = iio_read_channel_processed(adc_bat->channel[chan_index],
 138                         result);
 139         if (ret < 0)
 140                 pr_err("read channel error\n");
 141         else
 142                 *result *= 1000;
 143
 144         return ret;
 145 }
 146
 147 static int gab_get_property(struct power_supply *psy,
 148                 enum power_supply_property psp, union power_supply_propval *val)
 149 {
 150         struct gab *adc_bat;
 151         struct gab_platform_data *pdata;
 152         struct power_supply_info *bat_info;
 153         int result = 0;
 154         int ret = 0;
 155
 156         adc_bat = to_generic_bat(psy);
 157         if (!adc_bat) {
 158                 dev_err(&psy->dev, "no battery infos ?!\n");
 159                 return -EINVAL;
 160         }
 161         pdata = adc_bat->pdata;
 162         bat_info = &pdata->battery_info;
 163
 164         switch (psp) {
 165         case POWER_SUPPLY_PROP_STATUS:
 166                 val->intval = gab_get_status(adc_bat);
 167                 break;
 168         case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
 169                 val->intval = 0;
 170                 break;
 171         case POWER_SUPPLY_PROP_CHARGE_NOW:
 172                 val->intval = pdata->cal_charge(result);
 173                 break;
 174         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 175         case POWER_SUPPLY_PROP_CURRENT_NOW:
 176         case POWER_SUPPLY_PROP_POWER_NOW:
 177                 ret = read_channel(adc_bat, psp, &result);
 178                 if (ret < 0)
 179                         goto err;
 180                 val->intval = result;
 181                 break;
 182         case POWER_SUPPLY_PROP_TECHNOLOGY:
 183                 val->intval = bat_info->technology;
 184                 break;
 185         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 186                 val->intval = bat_info->voltage_min_design;
 187                 break;
 188         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 189                 val->intval = bat_info->voltage_max_design;
 190                 break;
 191         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 192                 val->intval = bat_info->charge_full_design;
 193                 break;
 194         case POWER_SUPPLY_PROP_MODEL_NAME:
 195                 val->strval = bat_info->name;
 196                 break;
 197         default:
 198                 return -EINVAL;
 199         }
 200 err:
 201         return ret;
 202 }
 203
 204 static void gab_work(struct work_struct *work)
 205 {
 206         struct gab *adc_bat;
 207         struct delayed_work *delayed_work;
 208         bool is_plugged;
 209         int status;
 210
 211         delayed_work = to_delayed_work(work);
 212         adc_bat = container_of(delayed_work, struct gab, bat_work);
 213         status = adc_bat->status;
 214
 215         is_plugged = power_supply_am_i_supplied(adc_bat->psy);
 216         adc_bat->cable_plugged = is_plugged;
 217
 218         if (!is_plugged)
 219                 adc_bat->status =  POWER_SUPPLY_STATUS_DISCHARGING;
 220         else if (gab_charge_finished(adc_bat))
 221                 adc_bat->status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 222         else
 223                 adc_bat->status = POWER_SUPPLY_STATUS_CHARGING;
 224
 225         if (status != adc_bat->status)
 226                 power_supply_changed(adc_bat->psy);
 227 }
 228
 229 static irqreturn_t gab_charged(int irq, void *dev_id)
 230 {
 231         struct gab *adc_bat = dev_id;
 232         struct gab_platform_data *pdata = adc_bat->pdata;
 233         int delay;
 234
 235         delay = pdata->jitter_delay ? pdata->jitter_delay : JITTER_DEFAULT;
 236         schedule_delayed_work(&adc_bat->bat_work,
 237                         msecs_to_jiffies(delay));
 238         return IRQ_HANDLED;
 239 }
 240
 241 static int gab_probe(struct platform_device *pdev)
 242 {
 243         struct gab *adc_bat;
 244         struct power_supply_desc *psy_desc;
 245         struct power_supply_config psy_cfg = {};
 246         struct gab_platform_data *pdata = pdev->dev.platform_data;
 247         enum power_supply_property *properties;
 248         int ret = 0;
 249         int chan;
 250         int index = ARRAY_SIZE(gab_props);
 251         bool any = false;
 252
 253         adc_bat = devm_kzalloc(&pdev->dev, sizeof(*adc_bat), GFP_KERNEL);
 254         if (!adc_bat) {
 255                 dev_err(&pdev->dev, "failed to allocate memory\n");
 256                 return -ENOMEM;
 257         }
 258
 259         psy_cfg.drv_data = adc_bat;
 260         psy_desc = &adc_bat->psy_desc;
 261         psy_desc->name = pdata->battery_info.name;
 262
 263         /* bootup default values for the battery */
 264         adc_bat->cable_plugged = false;
 265         adc_bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
 266         psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
 267         psy_desc->get_property = gab_get_property;
 268         psy_desc->external_power_changed = gab_ext_power_changed;
 269         adc_bat->pdata = pdata;
 270
 271         /*
 272          * copying the static properties and allocating extra memory for holding
 273          * the extra configurable properties received from platform data.
 274          */
 275         properties = kcalloc(ARRAY_SIZE(gab_props) +
 276                              ARRAY_SIZE(gab_chan_name),
 277                              sizeof(*properties),
 278                              GFP_KERNEL);
 279         if (!properties) {
 280                 ret = -ENOMEM;
 281                 goto first_mem_fail;
 282         }
 283
 284         memcpy(properties, gab_props, sizeof(gab_props));
 285
 286         /*
 287          * getting channel from iio and copying the battery properties
 288          * based on the channel supported by consumer device.
 289          */
 290         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 291                 adc_bat->channel[chan] = iio_channel_get(&pdev->dev,
 292                                                          gab_chan_name[chan]);
 293                 if (IS_ERR(adc_bat->channel[chan])) {
 294                         ret = PTR_ERR(adc_bat->channel[chan]);
 295                         adc_bat->channel[chan] = NULL;
 296                 } else {
 297                         /* copying properties for supported channels only */
 298                         int index2;
 299
 300                         for (index2 = 0; index2 < index; index2++) {
 301                                 if (properties[index2] == gab_dyn_props[chan])
 302                                         break;  /* already known */
 303                         }
 304                         if (index2 == index)    /* really new */
 305                                 properties[index++] = gab_dyn_props[chan];
 306                         any = true;
 307                 }
 308         }
 309
 310         /* none of the channels are supported so let's bail out */
 311         if (!any) {
 312                 ret = -ENODEV;
 313                 goto second_mem_fail;
 314         }
 315
 316         /*
 317          * Total number of properties is equal to static properties
 318          * plus the dynamic properties.Some properties may not be set
 319          * as come channels may be not be supported by the device.So
 320          * we need to take care of that.
 321          */
 322         psy_desc->properties = properties;
 323         psy_desc->num_properties = index;
 324
 325         adc_bat->psy = power_supply_register(&pdev->dev, psy_desc, &psy_cfg);
 326         if (IS_ERR(adc_bat->psy)) {
 327                 ret = PTR_ERR(adc_bat->psy);
 328                 goto err_reg_fail;
 329         }
 330
 331         INIT_DELAYED_WORK(&adc_bat->bat_work, gab_work);
 332
 333         if (gpio_is_valid(pdata->gpio_charge_finished)) {
 334                 int irq;
 335                 ret = gpio_request(pdata->gpio_charge_finished, "charged");
 336                 if (ret)
 337                         goto gpio_req_fail;
 338
 339                 irq = gpio_to_irq(pdata->gpio_charge_finished);
 340                 ret = request_any_context_irq(irq, gab_charged,
 341                                 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 342                                 "battery charged", adc_bat);
 343                 if (ret < 0)
 344                         goto err_gpio;
 345         }
 346
 347         platform_set_drvdata(pdev, adc_bat);
 348
 349         /* Schedule timer to check current status */
 350         schedule_delayed_work(&adc_bat->bat_work,
 351                         msecs_to_jiffies(0));
 352         return 0;
 353
 354 err_gpio:
 355         gpio_free(pdata->gpio_charge_finished);
 356 gpio_req_fail:
 357         power_supply_unregister(adc_bat->psy);
 358 err_reg_fail:
 359         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 360                 if (adc_bat->channel[chan])
 361                         iio_channel_release(adc_bat->channel[chan]);
 362         }
 363 second_mem_fail:
 364         kfree(properties);
 365 first_mem_fail:
 366         return ret;
 367 }
 368
 369 static int gab_remove(struct platform_device *pdev)
 370 {
 371         int chan;
 372         struct gab *adc_bat = platform_get_drvdata(pdev);
 373         struct gab_platform_data *pdata = adc_bat->pdata;
 374
 375         power_supply_unregister(adc_bat->psy);
 376
 377         if (gpio_is_valid(pdata->gpio_charge_finished)) {
 378                 free_irq(gpio_to_irq(pdata->gpio_charge_finished), adc_bat);
 379                 gpio_free(pdata->gpio_charge_finished);
 380         }
 381
 382         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 383                 if (adc_bat->channel[chan])
 384                         iio_channel_release(adc_bat->channel[chan]);
 385         }
 386
 387         kfree(adc_bat->psy_desc.properties);
 388         cancel_delayed_work_sync(&adc_bat->bat_work);
 389         return 0;
 390 }
 391
 392 static int __maybe_unused gab_suspend(struct device *dev)
 393 {
 394         struct gab *adc_bat = dev_get_drvdata(dev);
 395
 396         cancel_delayed_work_sync(&adc_bat->bat_work);
 397         adc_bat->status = POWER_SUPPLY_STATUS_UNKNOWN;
 398         return 0;
 399 }
 400
 401 static int __maybe_unused gab_resume(struct device *dev)
 402 {
 403         struct gab *adc_bat = dev_get_drvdata(dev);
 404         struct gab_platform_data *pdata = adc_bat->pdata;
 405         int delay;
 406
 407         delay = pdata->jitter_delay ? pdata->jitter_delay : JITTER_DEFAULT;
 408
 409         /* Schedule timer to check current status */
 410         schedule_delayed_work(&adc_bat->bat_work,
 411                         msecs_to_jiffies(delay));
 412         return 0;
 413 }
 414
 415 static SIMPLE_DEV_PM_OPS(gab_pm_ops, gab_suspend, gab_resume);
 416
 417 static struct platform_driver gab_driver = {
 418         .driver         = {
 419                 .name   = "generic-adc-battery",
 420                 .pm     = &gab_pm_ops,
 421         },
 422         .probe          = gab_probe,
 423         .remove         = gab_remove,
 424 };
 425 module_platform_driver(gab_driver);
 426
 427 MODULE_AUTHOR("anish kumar <anish198519851985@gmail.com>");
 428 MODULE_DESCRIPTION("generic battery driver using IIO");
 429 MODULE_LICENSE("GPL");