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 gab_platform_data *pdata;
 208         struct delayed_work *delayed_work;
 209         bool is_plugged;
 210         int status;
 211
 212         delayed_work = to_delayed_work(work);
 213         adc_bat = container_of(delayed_work, struct gab, bat_work);
 214         pdata = adc_bat->pdata;
 215         status = adc_bat->status;
 216
 217         is_plugged = power_supply_am_i_supplied(adc_bat->psy);
 218         adc_bat->cable_plugged = is_plugged;
 219
 220         if (!is_plugged)
 221                 adc_bat->status =  POWER_SUPPLY_STATUS_DISCHARGING;
 222         else if (gab_charge_finished(adc_bat))
 223                 adc_bat->status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 224         else
 225                 adc_bat->status = POWER_SUPPLY_STATUS_CHARGING;
 226
 227         if (status != adc_bat->status)
 228                 power_supply_changed(adc_bat->psy);
 229 }
 230
 231 static irqreturn_t gab_charged(int irq, void *dev_id)
 232 {
 233         struct gab *adc_bat = dev_id;
 234         struct gab_platform_data *pdata = adc_bat->pdata;
 235         int delay;
 236
 237         delay = pdata->jitter_delay ? pdata->jitter_delay : JITTER_DEFAULT;
 238         schedule_delayed_work(&adc_bat->bat_work,
 239                         msecs_to_jiffies(delay));
 240         return IRQ_HANDLED;
 241 }
 242
 243 static int gab_probe(struct platform_device *pdev)
 244 {
 245         struct gab *adc_bat;
 246         struct power_supply_desc *psy_desc;
 247         struct power_supply_config psy_cfg = {};
 248         struct gab_platform_data *pdata = pdev->dev.platform_data;
 249         int ret = 0;
 250         int chan;
 251         int index = ARRAY_SIZE(gab_props);
 252         bool any = false;
 253
 254         adc_bat = devm_kzalloc(&pdev->dev, sizeof(*adc_bat), GFP_KERNEL);
 255         if (!adc_bat) {
 256                 dev_err(&pdev->dev, "failed to allocate memory\n");
 257                 return -ENOMEM;
 258         }
 259
 260         psy_cfg.drv_data = adc_bat;
 261         psy_desc = &adc_bat->psy_desc;
 262         psy_desc->name = pdata->battery_info.name;
 263
 264         /* bootup default values for the battery */
 265         adc_bat->cable_plugged = false;
 266         adc_bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
 267         psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
 268         psy_desc->get_property = gab_get_property;
 269         psy_desc->external_power_changed = gab_ext_power_changed;
 270         adc_bat->pdata = pdata;
 271
 272         /*
 273          * copying the static properties and allocating extra memory for holding
 274          * the extra configurable properties received from platform data.
 275          */
 276         psy_desc->properties = kcalloc(ARRAY_SIZE(gab_props) +
 277                                         ARRAY_SIZE(gab_chan_name),
 278                                         sizeof(*psy_desc->properties),
 279                                         GFP_KERNEL);
 280         if (!psy_desc->properties) {
 281                 ret = -ENOMEM;
 282                 goto first_mem_fail;
 283         }
 284
 285         memcpy(psy_desc->properties, gab_props, sizeof(gab_props));
 286
 287         /*
 288          * getting channel from iio and copying the battery properties
 289          * based on the channel supported by consumer device.
 290          */
 291         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 292                 adc_bat->channel[chan] = iio_channel_get(&pdev->dev,
 293                                                          gab_chan_name[chan]);
 294                 if (IS_ERR(adc_bat->channel[chan])) {
 295                         ret = PTR_ERR(adc_bat->channel[chan]);
 296                         adc_bat->channel[chan] = NULL;
 297                 } else {
 298                         /* copying properties for supported channels only */
 299                         int index2;
 300
 301                         for (index2 = 0; index2 < index; index2++) {
 302                                 if (psy_desc->properties[index2] ==
 303                                     gab_dyn_props[chan])
 304                                         break;  /* already known */
 305                         }
 306                         if (index2 == index)    /* really new */
 307                                 psy_desc->properties[index++] =
 308                                         gab_dyn_props[chan];
 309                         any = true;
 310                 }
 311         }
 312
 313         /* none of the channels are supported so let's bail out */
 314         if (!any) {
 315                 ret = -ENODEV;
 316                 goto second_mem_fail;
 317         }
 318
 319         /*
 320          * Total number of properties is equal to static properties
 321          * plus the dynamic properties.Some properties may not be set
 322          * as come channels may be not be supported by the device.So
 323          * we need to take care of that.
 324          */
 325         psy_desc->num_properties = index;
 326
 327         adc_bat->psy = power_supply_register(&pdev->dev, psy_desc, &psy_cfg);
 328         if (IS_ERR(adc_bat->psy)) {
 329                 ret = PTR_ERR(adc_bat->psy);
 330                 goto err_reg_fail;
 331         }
 332
 333         INIT_DELAYED_WORK(&adc_bat->bat_work, gab_work);
 334
 335         if (gpio_is_valid(pdata->gpio_charge_finished)) {
 336                 int irq;
 337                 ret = gpio_request(pdata->gpio_charge_finished, "charged");
 338                 if (ret)
 339                         goto gpio_req_fail;
 340
 341                 irq = gpio_to_irq(pdata->gpio_charge_finished);
 342                 ret = request_any_context_irq(irq, gab_charged,
 343                                 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 344                                 "battery charged", adc_bat);
 345                 if (ret < 0)
 346                         goto err_gpio;
 347         }
 348
 349         platform_set_drvdata(pdev, adc_bat);
 350
 351         /* Schedule timer to check current status */
 352         schedule_delayed_work(&adc_bat->bat_work,
 353                         msecs_to_jiffies(0));
 354         return 0;
 355
 356 err_gpio:
 357         gpio_free(pdata->gpio_charge_finished);
 358 gpio_req_fail:
 359         power_supply_unregister(adc_bat->psy);
 360 err_reg_fail:
 361         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 362                 if (adc_bat->channel[chan])
 363                         iio_channel_release(adc_bat->channel[chan]);
 364         }
 365 second_mem_fail:
 366         kfree(psy_desc->properties);
 367 first_mem_fail:
 368         return ret;
 369 }
 370
 371 static int gab_remove(struct platform_device *pdev)
 372 {
 373         int chan;
 374         struct gab *adc_bat = platform_get_drvdata(pdev);
 375         struct gab_platform_data *pdata = adc_bat->pdata;
 376
 377         power_supply_unregister(adc_bat->psy);
 378
 379         if (gpio_is_valid(pdata->gpio_charge_finished)) {
 380                 free_irq(gpio_to_irq(pdata->gpio_charge_finished), adc_bat);
 381                 gpio_free(pdata->gpio_charge_finished);
 382         }
 383
 384         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 385                 if (adc_bat->channel[chan])
 386                         iio_channel_release(adc_bat->channel[chan]);
 387         }
 388
 389         kfree(adc_bat->psy_desc.properties);
 390         cancel_delayed_work_sync(&adc_bat->bat_work);
 391         return 0;
 392 }
 393
 394 static int __maybe_unused gab_suspend(struct device *dev)
 395 {
 396         struct gab *adc_bat = dev_get_drvdata(dev);
 397
 398         cancel_delayed_work_sync(&adc_bat->bat_work);
 399         adc_bat->status = POWER_SUPPLY_STATUS_UNKNOWN;
 400         return 0;
 401 }
 402
 403 static int __maybe_unused gab_resume(struct device *dev)
 404 {
 405         struct gab *adc_bat = dev_get_drvdata(dev);
 406         struct gab_platform_data *pdata = adc_bat->pdata;
 407         int delay;
 408
 409         delay = pdata->jitter_delay ? pdata->jitter_delay : JITTER_DEFAULT;
 410
 411         /* Schedule timer to check current status */
 412         schedule_delayed_work(&adc_bat->bat_work,
 413                         msecs_to_jiffies(delay));
 414         return 0;
 415 }
 416
 417 static SIMPLE_DEV_PM_OPS(gab_pm_ops, gab_suspend, gab_resume);
 418
 419 static struct platform_driver gab_driver = {
 420         .driver         = {
 421                 .name   = "generic-adc-battery",
 422                 .pm     = &gab_pm_ops,
 423         },
 424         .probe          = gab_probe,
 425         .remove         = gab_remove,
 426 };
 427 module_platform_driver(gab_driver);
 428
 429 MODULE_AUTHOR("anish kumar <anish198519851985@gmail.com>");
 430 MODULE_DESCRIPTION("generic battery driver using IIO");
 431 MODULE_LICENSE("GPL");