drivers/power/supply/max8997_charger.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // max8997_charger.c - Power supply consumer driver for the Maxim 8997/8966
   4 //
   5 //  Copyright (C) 2011 Samsung Electronics
   6 //  MyungJoo Ham <myungjoo.ham@samsung.com>
   7
   8 #include <linux/err.h>
   9 #include <linux/module.h>
  10 #include <linux/slab.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/power_supply.h>
  13 #include <linux/mfd/max8997.h>
  14 #include <linux/mfd/max8997-private.h>
  15
  16 /* MAX8997_REG_STATUS4 */
  17 #define DCINOK_SHIFT            1
  18 #define DCINOK_MASK             (1 << DCINOK_SHIFT)
  19 #define DETBAT_SHIFT            2
  20 #define DETBAT_MASK             (1 << DETBAT_SHIFT)
  21
  22 /* MAX8997_REG_MBCCTRL1 */
  23 #define TFCH_SHIFT              4
  24 #define TFCH_MASK               (7 << TFCH_SHIFT)
  25
  26 /* MAX8997_REG_MBCCTRL5 */
  27 #define ITOPOFF_SHIFT           0
  28 #define ITOPOFF_MASK            (0xF << ITOPOFF_SHIFT)
  29
  30 struct charger_data {
  31         struct device *dev;
  32         struct max8997_dev *iodev;
  33         struct power_supply *battery;
  34 };
  35
  36 static enum power_supply_property max8997_battery_props[] = {
  37         POWER_SUPPLY_PROP_STATUS, /* "FULL", "CHARGING" or "DISCHARGING". */
  38         POWER_SUPPLY_PROP_PRESENT, /* the presence of battery */
  39         POWER_SUPPLY_PROP_ONLINE, /* charger is active or not */
  40 };
  41
  42 /* Note that the charger control is done by a current regulator "CHARGER" */
  43 static int max8997_battery_get_property(struct power_supply *psy,
  44                 enum power_supply_property psp,
  45                 union power_supply_propval *val)
  46 {
  47         struct charger_data *charger = power_supply_get_drvdata(psy);
  48         struct i2c_client *i2c = charger->iodev->i2c;
  49         int ret;
  50         u8 reg;
  51
  52         switch (psp) {
  53         case POWER_SUPPLY_PROP_STATUS:
  54                 val->intval = 0;
  55                 ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
  56                 if (ret)
  57                         return ret;
  58                 if ((reg & (1 << 0)) == 0x1)
  59                         val->intval = POWER_SUPPLY_STATUS_FULL;
  60                 else if ((reg & DCINOK_MASK))
  61                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
  62                 else
  63                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
  64
  65                 break;
  66         case POWER_SUPPLY_PROP_PRESENT:
  67                 val->intval = 0;
  68                 ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
  69                 if (ret)
  70                         return ret;
  71                 if ((reg & DETBAT_MASK) == 0x0)
  72                         val->intval = 1;
  73
  74                 break;
  75         case POWER_SUPPLY_PROP_ONLINE:
  76                 val->intval = 0;
  77                 ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
  78                 if (ret)
  79                         return ret;
  80                 if (reg & DCINOK_MASK)
  81                         val->intval = 1;
  82
  83                 break;
  84         default:
  85                 return -EINVAL;
  86         }
  87
  88         return 0;
  89 }
  90
  91 static const struct power_supply_desc max8997_battery_desc = {
  92         .name           = "max8997_pmic",
  93         .type           = POWER_SUPPLY_TYPE_BATTERY,
  94         .get_property   = max8997_battery_get_property,
  95         .properties     = max8997_battery_props,
  96         .num_properties = ARRAY_SIZE(max8997_battery_props),
  97 };
  98
  99 static int max8997_battery_probe(struct platform_device *pdev)
 100 {
 101         int ret = 0;
 102         struct charger_data *charger;
 103         struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 104         struct i2c_client *i2c = iodev->i2c;
 105         struct max8997_platform_data *pdata = iodev->pdata;
 106         struct power_supply_config psy_cfg = {};
 107
 108         if (!pdata) {
 109                 dev_err(&pdev->dev, "No platform data supplied.\n");
 110                 return -EINVAL;
 111         }
 112
 113         if (pdata->eoc_mA) {
 114                 int val = (pdata->eoc_mA - 50) / 10;
 115                 if (val < 0)
 116                         val = 0;
 117                 if (val > 0xf)
 118                         val = 0xf;
 119
 120                 ret = max8997_update_reg(i2c, MAX8997_REG_MBCCTRL5,
 121                                 val << ITOPOFF_SHIFT, ITOPOFF_MASK);
 122                 if (ret < 0) {
 123                         dev_err(&pdev->dev, "Cannot use i2c bus.\n");
 124                         return ret;
 125                 }
 126         }
 127         switch (pdata->timeout) {
 128         case 5:
 129                 ret = max8997_update_reg(i2c, MAX8997_REG_MBCCTRL1,
 130                                 0x2 << TFCH_SHIFT, TFCH_MASK);
 131                 break;
 132         case 6:
 133                 ret = max8997_update_reg(i2c, MAX8997_REG_MBCCTRL1,
 134                                 0x3 << TFCH_SHIFT, TFCH_MASK);
 135                 break;
 136         case 7:
 137                 ret = max8997_update_reg(i2c, MAX8997_REG_MBCCTRL1,
 138                                 0x4 << TFCH_SHIFT, TFCH_MASK);
 139                 break;
 140         case 0:
 141                 ret = max8997_update_reg(i2c, MAX8997_REG_MBCCTRL1,
 142                                 0x7 << TFCH_SHIFT, TFCH_MASK);
 143                 break;
 144         default:
 145                 dev_err(&pdev->dev, "incorrect timeout value (%d)\n",
 146                                 pdata->timeout);
 147                 return -EINVAL;
 148         }
 149         if (ret < 0) {
 150                 dev_err(&pdev->dev, "Cannot use i2c bus.\n");
 151                 return ret;
 152         }
 153
 154         charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
 155         if (!charger)
 156                 return -ENOMEM;
 157
 158         platform_set_drvdata(pdev, charger);
 159
 160         charger->dev = &pdev->dev;
 161         charger->iodev = iodev;
 162
 163         psy_cfg.drv_data = charger;
 164
 165         charger->battery = devm_power_supply_register(&pdev->dev,
 166                                                  &max8997_battery_desc,
 167                                                  &psy_cfg);
 168         if (IS_ERR(charger->battery)) {
 169                 dev_err(&pdev->dev, "failed: power supply register\n");
 170                 return PTR_ERR(charger->battery);
 171         }
 172
 173         return 0;
 174 }
 175
 176 static const struct platform_device_id max8997_battery_id[] = {
 177         { "max8997-battery", 0 },
 178         { }
 179 };
 180 MODULE_DEVICE_TABLE(platform, max8997_battery_id);
 181
 182 static struct platform_driver max8997_battery_driver = {
 183         .driver = {
 184                 .name = "max8997-battery",
 185         },
 186         .probe = max8997_battery_probe,
 187         .id_table = max8997_battery_id,
 188 };
 189 module_platform_driver(max8997_battery_driver);
 190
 191 MODULE_DESCRIPTION("MAXIM 8997/8966 battery control driver");
 192 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
 193 MODULE_LICENSE("GPL");