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