linux/drivers/power/max17040_battery.c
<<
>>
Prefs
   1/*
   2 *  max17040_battery.c
   3 *  fuel-gauge systems for lithium-ion (Li+) batteries
   4 *
   5 *  Copyright (C) 2009 Samsung Electronics
   6 *  Minkyu Kang <mk7.kang@samsung.com>
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License version 2 as
  10 * published by the Free Software Foundation.
  11 */
  12
  13#include <linux/module.h>
  14#include <linux/init.h>
  15#include <linux/platform_device.h>
  16#include <linux/mutex.h>
  17#include <linux/err.h>
  18#include <linux/i2c.h>
  19#include <linux/delay.h>
  20#include <linux/power_supply.h>
  21#include <linux/max17040_battery.h>
  22#include <linux/slab.h>
  23
  24#define MAX17040_VCELL_MSB      0x02
  25#define MAX17040_VCELL_LSB      0x03
  26#define MAX17040_SOC_MSB        0x04
  27#define MAX17040_SOC_LSB        0x05
  28#define MAX17040_MODE_MSB       0x06
  29#define MAX17040_MODE_LSB       0x07
  30#define MAX17040_VER_MSB        0x08
  31#define MAX17040_VER_LSB        0x09
  32#define MAX17040_RCOMP_MSB      0x0C
  33#define MAX17040_RCOMP_LSB      0x0D
  34#define MAX17040_CMD_MSB        0xFE
  35#define MAX17040_CMD_LSB        0xFF
  36
  37#define MAX17040_DELAY          1000
  38#define MAX17040_BATTERY_FULL   95
  39
  40struct max17040_chip {
  41        struct i2c_client               *client;
  42        struct delayed_work             work;
  43        struct power_supply             battery;
  44        struct max17040_platform_data   *pdata;
  45
  46        /* State Of Connect */
  47        int online;
  48        /* battery voltage */
  49        int vcell;
  50        /* battery capacity */
  51        int soc;
  52        /* State Of Charge */
  53        int status;
  54};
  55
  56static int max17040_get_property(struct power_supply *psy,
  57                            enum power_supply_property psp,
  58                            union power_supply_propval *val)
  59{
  60        struct max17040_chip *chip = container_of(psy,
  61                                struct max17040_chip, battery);
  62
  63        switch (psp) {
  64        case POWER_SUPPLY_PROP_STATUS:
  65                val->intval = chip->status;
  66                break;
  67        case POWER_SUPPLY_PROP_ONLINE:
  68                val->intval = chip->online;
  69                break;
  70        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
  71                val->intval = chip->vcell;
  72                break;
  73        case POWER_SUPPLY_PROP_CAPACITY:
  74                val->intval = chip->soc;
  75                break;
  76        default:
  77                return -EINVAL;
  78        }
  79        return 0;
  80}
  81
  82static int max17040_write_reg(struct i2c_client *client, int reg, u8 value)
  83{
  84        int ret;
  85
  86        ret = i2c_smbus_write_byte_data(client, reg, value);
  87
  88        if (ret < 0)
  89                dev_err(&client->dev, "%s: err %d\n", __func__, ret);
  90
  91        return ret;
  92}
  93
  94static int max17040_read_reg(struct i2c_client *client, int reg)
  95{
  96        int ret;
  97
  98        ret = i2c_smbus_read_byte_data(client, reg);
  99
 100        if (ret < 0)
 101                dev_err(&client->dev, "%s: err %d\n", __func__, ret);
 102
 103        return ret;
 104}
 105
 106static void max17040_reset(struct i2c_client *client)
 107{
 108        max17040_write_reg(client, MAX17040_CMD_MSB, 0x54);
 109        max17040_write_reg(client, MAX17040_CMD_LSB, 0x00);
 110}
 111
 112static void max17040_get_vcell(struct i2c_client *client)
 113{
 114        struct max17040_chip *chip = i2c_get_clientdata(client);
 115        u8 msb;
 116        u8 lsb;
 117
 118        msb = max17040_read_reg(client, MAX17040_VCELL_MSB);
 119        lsb = max17040_read_reg(client, MAX17040_VCELL_LSB);
 120
 121        chip->vcell = (msb << 4) + (lsb >> 4);
 122}
 123
 124static void max17040_get_soc(struct i2c_client *client)
 125{
 126        struct max17040_chip *chip = i2c_get_clientdata(client);
 127        u8 msb;
 128        u8 lsb;
 129
 130        msb = max17040_read_reg(client, MAX17040_SOC_MSB);
 131        lsb = max17040_read_reg(client, MAX17040_SOC_LSB);
 132
 133        chip->soc = msb;
 134}
 135
 136static void max17040_get_version(struct i2c_client *client)
 137{
 138        u8 msb;
 139        u8 lsb;
 140
 141        msb = max17040_read_reg(client, MAX17040_VER_MSB);
 142        lsb = max17040_read_reg(client, MAX17040_VER_LSB);
 143
 144        dev_info(&client->dev, "MAX17040 Fuel-Gauge Ver %d%d\n", msb, lsb);
 145}
 146
 147static void max17040_get_online(struct i2c_client *client)
 148{
 149        struct max17040_chip *chip = i2c_get_clientdata(client);
 150
 151        if (chip->pdata->battery_online)
 152                chip->online = chip->pdata->battery_online();
 153        else
 154                chip->online = 1;
 155}
 156
 157static void max17040_get_status(struct i2c_client *client)
 158{
 159        struct max17040_chip *chip = i2c_get_clientdata(client);
 160
 161        if (!chip->pdata->charger_online || !chip->pdata->charger_enable) {
 162                chip->status = POWER_SUPPLY_STATUS_UNKNOWN;
 163                return;
 164        }
 165
 166        if (chip->pdata->charger_online()) {
 167                if (chip->pdata->charger_enable())
 168                        chip->status = POWER_SUPPLY_STATUS_CHARGING;
 169                else
 170                        chip->status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 171        } else {
 172                chip->status = POWER_SUPPLY_STATUS_DISCHARGING;
 173        }
 174
 175        if (chip->soc > MAX17040_BATTERY_FULL)
 176                chip->status = POWER_SUPPLY_STATUS_FULL;
 177}
 178
 179static void max17040_work(struct work_struct *work)
 180{
 181        struct max17040_chip *chip;
 182
 183        chip = container_of(work, struct max17040_chip, work.work);
 184
 185        max17040_get_vcell(chip->client);
 186        max17040_get_soc(chip->client);
 187        max17040_get_online(chip->client);
 188        max17040_get_status(chip->client);
 189
 190        schedule_delayed_work(&chip->work, MAX17040_DELAY);
 191}
 192
 193static enum power_supply_property max17040_battery_props[] = {
 194        POWER_SUPPLY_PROP_STATUS,
 195        POWER_SUPPLY_PROP_ONLINE,
 196        POWER_SUPPLY_PROP_VOLTAGE_NOW,
 197        POWER_SUPPLY_PROP_CAPACITY,
 198};
 199
 200static int max17040_probe(struct i2c_client *client,
 201                        const struct i2c_device_id *id)
 202{
 203        struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
 204        struct max17040_chip *chip;
 205        int ret;
 206
 207        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
 208                return -EIO;
 209
 210        chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
 211        if (!chip)
 212                return -ENOMEM;
 213
 214        chip->client = client;
 215        chip->pdata = client->dev.platform_data;
 216
 217        i2c_set_clientdata(client, chip);
 218
 219        chip->battery.name              = "battery";
 220        chip->battery.type              = POWER_SUPPLY_TYPE_BATTERY;
 221        chip->battery.get_property      = max17040_get_property;
 222        chip->battery.properties        = max17040_battery_props;
 223        chip->battery.num_properties    = ARRAY_SIZE(max17040_battery_props);
 224
 225        ret = power_supply_register(&client->dev, &chip->battery);
 226        if (ret) {
 227                dev_err(&client->dev, "failed: power supply register\n");
 228                return ret;
 229        }
 230
 231        max17040_reset(client);
 232        max17040_get_version(client);
 233
 234        INIT_DEFERRABLE_WORK(&chip->work, max17040_work);
 235        schedule_delayed_work(&chip->work, MAX17040_DELAY);
 236
 237        return 0;
 238}
 239
 240static int max17040_remove(struct i2c_client *client)
 241{
 242        struct max17040_chip *chip = i2c_get_clientdata(client);
 243
 244        power_supply_unregister(&chip->battery);
 245        cancel_delayed_work(&chip->work);
 246        return 0;
 247}
 248
 249#ifdef CONFIG_PM_SLEEP
 250
 251static int max17040_suspend(struct device *dev)
 252{
 253        struct i2c_client *client = to_i2c_client(dev);
 254        struct max17040_chip *chip = i2c_get_clientdata(client);
 255
 256        cancel_delayed_work(&chip->work);
 257        return 0;
 258}
 259
 260static int max17040_resume(struct device *dev)
 261{
 262        struct i2c_client *client = to_i2c_client(dev);
 263        struct max17040_chip *chip = i2c_get_clientdata(client);
 264
 265        schedule_delayed_work(&chip->work, MAX17040_DELAY);
 266        return 0;
 267}
 268
 269static SIMPLE_DEV_PM_OPS(max17040_pm_ops, max17040_suspend, max17040_resume);
 270#define MAX17040_PM_OPS (&max17040_pm_ops)
 271
 272#else
 273
 274#define MAX17040_PM_OPS NULL
 275
 276#endif /* CONFIG_PM_SLEEP */
 277
 278static const struct i2c_device_id max17040_id[] = {
 279        { "max17040", 0 },
 280        { }
 281};
 282MODULE_DEVICE_TABLE(i2c, max17040_id);
 283
 284static struct i2c_driver max17040_i2c_driver = {
 285        .driver = {
 286                .name   = "max17040",
 287                .pm     = MAX17040_PM_OPS,
 288        },
 289        .probe          = max17040_probe,
 290        .remove         = max17040_remove,
 291        .id_table       = max17040_id,
 292};
 293module_i2c_driver(max17040_i2c_driver);
 294
 295MODULE_AUTHOR("Minkyu Kang <mk7.kang@samsung.com>");
 296MODULE_DESCRIPTION("MAX17040 Fuel Gauge");
 297MODULE_LICENSE("GPL");
 298
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.