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         return ret;
 142 }
 143
 144 static int gab_get_property(struct power_supply *psy,
 145                 enum power_supply_property psp, union power_supply_propval *val)
 146 {
 147         struct gab *adc_bat;
 148         struct gab_platform_data *pdata;
 149         struct power_supply_info *bat_info;
 150         int result = 0;
 151         int ret = 0;
 152
 153         adc_bat = to_generic_bat(psy);
 154         if (!adc_bat) {
 155                 dev_err(&psy->dev, "no battery infos ?!\n");
 156                 return -EINVAL;
 157         }
 158         pdata = adc_bat->pdata;
 159         bat_info = &pdata->battery_info;
 160
 161         switch (psp) {
 162         case POWER_SUPPLY_PROP_STATUS:
 163                 val->intval = gab_get_status(adc_bat);
 164                 break;
 165         case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
 166                 val->intval = 0;
 167                 break;
 168         case POWER_SUPPLY_PROP_CHARGE_NOW:
 169                 val->intval = pdata->cal_charge(result);
 170                 break;
 171         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 172         case POWER_SUPPLY_PROP_CURRENT_NOW:
 173         case POWER_SUPPLY_PROP_POWER_NOW:
 174                 ret = read_channel(adc_bat, psp, &result);
 175                 if (ret < 0)
 176                         goto err;
 177                 val->intval = result;
 178                 break;
 179         case POWER_SUPPLY_PROP_TECHNOLOGY:
 180                 val->intval = bat_info->technology;
 181                 break;
 182         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 183                 val->intval = bat_info->voltage_min_design;
 184                 break;
 185         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 186                 val->intval = bat_info->voltage_max_design;
 187                 break;
 188         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 189                 val->intval = bat_info->charge_full_design;
 190                 break;
 191         case POWER_SUPPLY_PROP_MODEL_NAME:
 192                 val->strval = bat_info->name;
 193                 break;
 194         default:
 195                 return -EINVAL;
 196         }
 197 err:
 198         return ret;
 199 }
 200
 201 static void gab_work(struct work_struct *work)
 202 {
 203         struct gab *adc_bat;
 204         struct delayed_work *delayed_work;
 205         bool is_plugged;
 206         int status;
 207
 208         delayed_work = to_delayed_work(work);
 209         adc_bat = container_of(delayed_work, struct gab, bat_work);
 210         status = adc_bat->status;
 211
 212         is_plugged = power_supply_am_i_supplied(adc_bat->psy);
 213         adc_bat->cable_plugged = is_plugged;
 214
 215         if (!is_plugged)
 216                 adc_bat->status =  POWER_SUPPLY_STATUS_DISCHARGING;
 217         else if (gab_charge_finished(adc_bat))
 218                 adc_bat->status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 219         else
 220                 adc_bat->status = POWER_SUPPLY_STATUS_CHARGING;
 221
 222         if (status != adc_bat->status)
 223                 power_supply_changed(adc_bat->psy);
 224 }
 225
 226 static irqreturn_t gab_charged(int irq, void *dev_id)
 227 {
 228         struct gab *adc_bat = dev_id;
 229         struct gab_platform_data *pdata = adc_bat->pdata;
 230         int delay;
 231
 232         delay = pdata->jitter_delay ? pdata->jitter_delay : JITTER_DEFAULT;
 233         schedule_delayed_work(&adc_bat->bat_work,
 234                         msecs_to_jiffies(delay));
 235         return IRQ_HANDLED;
 236 }
 237
 238 static int gab_probe(struct platform_device *pdev)
 239 {
 240         struct gab *adc_bat;
 241         struct power_supply_desc *psy_desc;
 242         struct power_supply_config psy_cfg = {};
 243         struct gab_platform_data *pdata = pdev->dev.platform_data;
 244         enum power_supply_property *properties;
 245         int ret = 0;
 246         int chan;
 247         int index = 0;
 248
 249         adc_bat = devm_kzalloc(&pdev->dev, sizeof(*adc_bat), GFP_KERNEL);
 250         if (!adc_bat) {
 251                 dev_err(&pdev->dev, "failed to allocate memory\n");
 252                 return -ENOMEM;
 253         }
 254
 255         psy_cfg.drv_data = adc_bat;
 256         psy_desc = &adc_bat->psy_desc;
 257         psy_desc->name = pdata->battery_info.name;
 258
 259         /* bootup default values for the battery */
 260         adc_bat->cable_plugged = false;
 261         adc_bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
 262         psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
 263         psy_desc->get_property = gab_get_property;
 264         psy_desc->external_power_changed = gab_ext_power_changed;
 265         adc_bat->pdata = pdata;
 266
 267         /*
 268          * copying the static properties and allocating extra memory for holding
 269          * the extra configurable properties received from platform data.
 270          */
 271         psy_desc->properties = kcalloc(ARRAY_SIZE(gab_props) +
 272                                         ARRAY_SIZE(gab_chan_name),
 273                                         sizeof(*psy_desc->properties),
 274                                         GFP_KERNEL);
 275         if (!psy_desc->properties) {
 276                 ret = -ENOMEM;
 277                 goto first_mem_fail;
 278         }
 279
 280         memcpy(psy_desc->properties, gab_props, sizeof(gab_props));
 281         properties = (enum power_supply_property *)
 282                         ((char *)psy_desc->properties + sizeof(gab_props));
 283
 284         /*
 285          * getting channel from iio and copying the battery properties
 286          * based on the channel supported by consumer device.
 287          */
 288         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 289                 adc_bat->channel[chan] = iio_channel_get(&pdev->dev,
 290                                                          gab_chan_name[chan]);
 291                 if (IS_ERR(adc_bat->channel[chan])) {
 292                         ret = PTR_ERR(adc_bat->channel[chan]);
 293                         adc_bat->channel[chan] = NULL;
 294                 } else {
 295                         /* copying properties for supported channels only */
 296                         memcpy(properties + sizeof(*(psy_desc->properties)) * index,
 297                                         &gab_dyn_props[chan],
 298                                         sizeof(gab_dyn_props[chan]));
 299                         index++;
 300                 }
 301         }
 302
 303         /* none of the channels are supported so let's bail out */
 304         if (index == 0) {
 305                 ret = -ENODEV;
 306                 goto second_mem_fail;
 307         }
 308
 309         /*
 310          * Total number of properties is equal to static properties
 311          * plus the dynamic properties.Some properties may not be set
 312          * as come channels may be not be supported by the device.So
 313          * we need to take care of that.
 314          */
 315         psy_desc->num_properties = ARRAY_SIZE(gab_props) + index;
 316
 317         adc_bat->psy = power_supply_register(&pdev->dev, psy_desc, &psy_cfg);
 318         if (IS_ERR(adc_bat->psy)) {
 319                 ret = PTR_ERR(adc_bat->psy);
 320                 goto err_reg_fail;
 321         }
 322
 323         INIT_DELAYED_WORK(&adc_bat->bat_work, gab_work);
 324
 325         if (gpio_is_valid(pdata->gpio_charge_finished)) {
 326                 int irq;
 327                 ret = gpio_request(pdata->gpio_charge_finished, "charged");
 328                 if (ret)
 329                         goto gpio_req_fail;
 330
 331                 irq = gpio_to_irq(pdata->gpio_charge_finished);
 332                 ret = request_any_context_irq(irq, gab_charged,
 333                                 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 334                                 "battery charged", adc_bat);
 335                 if (ret < 0)
 336                         goto err_gpio;
 337         }
 338
 339         platform_set_drvdata(pdev, adc_bat);
 340
 341         /* Schedule timer to check current status */
 342         schedule_delayed_work(&adc_bat->bat_work,
 343                         msecs_to_jiffies(0));
 344         return 0;
 345
 346 err_gpio:
 347         gpio_free(pdata->gpio_charge_finished);
 348 gpio_req_fail:
 349         power_supply_unregister(adc_bat->psy);
 350 err_reg_fail:
 351         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 352                 if (adc_bat->channel[chan])
 353                         iio_channel_release(adc_bat->channel[chan]);
 354         }
 355 second_mem_fail:
 356         kfree(psy_desc->properties);
 357 first_mem_fail:
 358         return ret;
 359 }
 360
 361 static int gab_remove(struct platform_device *pdev)
 362 {
 363         int chan;
 364         struct gab *adc_bat = platform_get_drvdata(pdev);
 365         struct gab_platform_data *pdata = adc_bat->pdata;
 366
 367         power_supply_unregister(adc_bat->psy);
 368
 369         if (gpio_is_valid(pdata->gpio_charge_finished)) {
 370                 free_irq(gpio_to_irq(pdata->gpio_charge_finished), adc_bat);
 371                 gpio_free(pdata->gpio_charge_finished);
 372         }
 373
 374         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 375                 if (adc_bat->channel[chan])
 376                         iio_channel_release(adc_bat->channel[chan]);
 377         }
 378
 379         kfree(adc_bat->psy_desc.properties);
 380         cancel_delayed_work(&adc_bat->bat_work);
 381         return 0;
 382 }
 383
 384 static int __maybe_unused gab_suspend(struct device *dev)
 385 {
 386         struct gab *adc_bat = dev_get_drvdata(dev);
 387
 388         cancel_delayed_work_sync(&adc_bat->bat_work);
 389         adc_bat->status = POWER_SUPPLY_STATUS_UNKNOWN;
 390         return 0;
 391 }
 392
 393 static int __maybe_unused gab_resume(struct device *dev)
 394 {
 395         struct gab *adc_bat = dev_get_drvdata(dev);
 396         struct gab_platform_data *pdata = adc_bat->pdata;
 397         int delay;
 398
 399         delay = pdata->jitter_delay ? pdata->jitter_delay : JITTER_DEFAULT;
 400
 401         /* Schedule timer to check current status */
 402         schedule_delayed_work(&adc_bat->bat_work,
 403                         msecs_to_jiffies(delay));
 404         return 0;
 405 }
 406
 407 static SIMPLE_DEV_PM_OPS(gab_pm_ops, gab_suspend, gab_resume);
 408
 409 static struct platform_driver gab_driver = {
 410         .driver         = {
 411                 .name   = "generic-adc-battery",
 412                 .pm     = &gab_pm_ops,
 413         },
 414         .probe          = gab_probe,
 415         .remove         = gab_remove,
 416 };
 417 module_platform_driver(gab_driver);
 418
 419 MODULE_AUTHOR("anish kumar <anish198519851985@gmail.com>");
 420 MODULE_DESCRIPTION("generic battery driver using IIO");
 421 MODULE_LICENSE("GPL");