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

   1 /*
   2  * Generic battery driver code using IIO
   3  * Copyright (C) 2012, Anish Kumar <[email protected]>
   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         int ret = 0;
 245         int chan;
 246         int index = ARRAY_SIZE(gab_props);
 247         bool any = false;
 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
 282         /*
 283          * getting channel from iio and copying the battery properties
 284          * based on the channel supported by consumer device.
 285          */
 286         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 287                 adc_bat->channel[chan] = iio_channel_get(&pdev->dev,
 288                                                          gab_chan_name[chan]);
 289                 if (IS_ERR(adc_bat->channel[chan])) {
 290                         ret = PTR_ERR(adc_bat->channel[chan]);
 291                         adc_bat->channel[chan] = NULL;
 292                 } else {
 293                         /* copying properties for supported channels only */
 294                         int index2;
 295
 296                         for (index2 = 0; index2 < index; index2++) {
 297                                 if (psy_desc->properties[index2] ==
 298                                     gab_dyn_props[chan])
 299                                         break;  /* already known */
 300                         }
 301                         if (index2 == index)    /* really new */
 302                                 psy_desc->properties[index++] =
 303                                         gab_dyn_props[chan];
 304                         any = true;
 305                 }
 306         }
 307
 308         /* none of the channels are supported so let's bail out */
 309         if (!any) {
 310                 ret = -ENODEV;
 311                 goto second_mem_fail;
 312         }
 313
 314         /*
 315          * Total number of properties is equal to static properties
 316          * plus the dynamic properties.Some properties may not be set
 317          * as come channels may be not be supported by the device.So
 318          * we need to take care of that.
 319          */
 320         psy_desc->num_properties = index;
 321
 322         adc_bat->psy = power_supply_register(&pdev->dev, psy_desc, &psy_cfg);
 323         if (IS_ERR(adc_bat->psy)) {
 324                 ret = PTR_ERR(adc_bat->psy);
 325                 goto err_reg_fail;
 326         }
 327
 328         INIT_DELAYED_WORK(&adc_bat->bat_work, gab_work);
 329
 330         if (gpio_is_valid(pdata->gpio_charge_finished)) {
 331                 int irq;
 332                 ret = gpio_request(pdata->gpio_charge_finished, "charged");
 333                 if (ret)
 334                         goto gpio_req_fail;
 335
 336                 irq = gpio_to_irq(pdata->gpio_charge_finished);
 337                 ret = request_any_context_irq(irq, gab_charged,
 338                                 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 339                                 "battery charged", adc_bat);
 340                 if (ret < 0)
 341                         goto err_gpio;
 342         }
 343
 344         platform_set_drvdata(pdev, adc_bat);
 345
 346         /* Schedule timer to check current status */
 347         schedule_delayed_work(&adc_bat->bat_work,
 348                         msecs_to_jiffies(0));
 349         return 0;
 350
 351 err_gpio:
 352         gpio_free(pdata->gpio_charge_finished);
 353 gpio_req_fail:
 354         power_supply_unregister(adc_bat->psy);
 355 err_reg_fail:
 356         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 357                 if (adc_bat->channel[chan])
 358                         iio_channel_release(adc_bat->channel[chan]);
 359         }
 360 second_mem_fail:
 361         kfree(psy_desc->properties);
 362 first_mem_fail:
 363         return ret;
 364 }
 365
 366 static int gab_remove(struct platform_device *pdev)
 367 {
 368         int chan;
 369         struct gab *adc_bat = platform_get_drvdata(pdev);
 370         struct gab_platform_data *pdata = adc_bat->pdata;
 371
 372         power_supply_unregister(adc_bat->psy);
 373
 374         if (gpio_is_valid(pdata->gpio_charge_finished)) {
 375                 free_irq(gpio_to_irq(pdata->gpio_charge_finished), adc_bat);
 376                 gpio_free(pdata->gpio_charge_finished);
 377         }
 378
 379         for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
 380                 if (adc_bat->channel[chan])
 381                         iio_channel_release(adc_bat->channel[chan]);
 382         }
 383
 384         kfree(adc_bat->psy_desc.properties);
 385         cancel_delayed_work(&adc_bat->bat_work);
 386         return 0;
 387 }
 388
 389 static int __maybe_unused gab_suspend(struct device *dev)
 390 {
 391         struct gab *adc_bat = dev_get_drvdata(dev);
 392
 393         cancel_delayed_work_sync(&adc_bat->bat_work);
 394         adc_bat->status = POWER_SUPPLY_STATUS_UNKNOWN;
 395         return 0;
 396 }
 397
 398 static int __maybe_unused gab_resume(struct device *dev)
 399 {
 400         struct gab *adc_bat = dev_get_drvdata(dev);
 401         struct gab_platform_data *pdata = adc_bat->pdata;
 402         int delay;
 403
 404         delay = pdata->jitter_delay ? pdata->jitter_delay : JITTER_DEFAULT;
 405
 406         /* Schedule timer to check current status */
 407         schedule_delayed_work(&adc_bat->bat_work,
 408                         msecs_to_jiffies(delay));
 409         return 0;
 410 }
 411
 412 static SIMPLE_DEV_PM_OPS(gab_pm_ops, gab_suspend, gab_resume);
 413
 414 static struct platform_driver gab_driver = {
 415         .driver         = {
 416                 .name   = "generic-adc-battery",
 417                 .pm     = &gab_pm_ops,
 418         },
 419         .probe          = gab_probe,
 420         .remove         = gab_remove,
 421 };
 422 module_platform_driver(gab_driver);
 423
 424 MODULE_AUTHOR("anish kumar <[email protected]>");
 425 MODULE_DESCRIPTION("generic battery driver using IIO");
 426 MODULE_LICENSE("GPL");