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