Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / power / max17042_battery.c
diff --git a/kernel/drivers/power/max17042_battery.c b/kernel/drivers/power/max17042_battery.c
new file mode 100644 (file)
index 0000000..6cc5e87
--- /dev/null
@@ -0,0 +1,847 @@
+/*
+ * Fuel gauge driver for Maxim 17042 / 8966 / 8997
+ *  Note that Maxim 8966 and 8997 are mfd and this is its subdevice.
+ *
+ * Copyright (C) 2011 Samsung Electronics
+ * MyungJoo Ham <myungjoo.ham@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * This driver is based on max17040_battery.c
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/pm.h>
+#include <linux/mod_devicetable.h>
+#include <linux/power_supply.h>
+#include <linux/power/max17042_battery.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+/* Status register bits */
+#define STATUS_POR_BIT         (1 << 1)
+#define STATUS_BST_BIT         (1 << 3)
+#define STATUS_VMN_BIT         (1 << 8)
+#define STATUS_TMN_BIT         (1 << 9)
+#define STATUS_SMN_BIT         (1 << 10)
+#define STATUS_BI_BIT          (1 << 11)
+#define STATUS_VMX_BIT         (1 << 12)
+#define STATUS_TMX_BIT         (1 << 13)
+#define STATUS_SMX_BIT         (1 << 14)
+#define STATUS_BR_BIT          (1 << 15)
+
+/* Interrupt mask bits */
+#define CONFIG_ALRT_BIT_ENBL   (1 << 2)
+#define STATUS_INTR_SOCMIN_BIT (1 << 10)
+#define STATUS_INTR_SOCMAX_BIT (1 << 14)
+
+#define VFSOC0_LOCK            0x0000
+#define VFSOC0_UNLOCK          0x0080
+#define MODEL_UNLOCK1  0X0059
+#define MODEL_UNLOCK2  0X00C4
+#define MODEL_LOCK1            0X0000
+#define MODEL_LOCK2            0X0000
+
+#define dQ_ACC_DIV     0x4
+#define dP_ACC_100     0x1900
+#define dP_ACC_200     0x3200
+
+struct max17042_chip {
+       struct i2c_client *client;
+       struct regmap *regmap;
+       struct power_supply *battery;
+       enum max170xx_chip_type chip_type;
+       struct max17042_platform_data *pdata;
+       struct work_struct work;
+       int    init_complete;
+};
+
+static enum power_supply_property max17042_battery_props[] = {
+       POWER_SUPPLY_PROP_PRESENT,
+       POWER_SUPPLY_PROP_CYCLE_COUNT,
+       POWER_SUPPLY_PROP_VOLTAGE_MAX,
+       POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
+       POWER_SUPPLY_PROP_VOLTAGE_NOW,
+       POWER_SUPPLY_PROP_VOLTAGE_AVG,
+       POWER_SUPPLY_PROP_VOLTAGE_OCV,
+       POWER_SUPPLY_PROP_CAPACITY,
+       POWER_SUPPLY_PROP_CHARGE_FULL,
+       POWER_SUPPLY_PROP_CHARGE_COUNTER,
+       POWER_SUPPLY_PROP_TEMP,
+       POWER_SUPPLY_PROP_CURRENT_NOW,
+       POWER_SUPPLY_PROP_CURRENT_AVG,
+};
+
+static int max17042_get_property(struct power_supply *psy,
+                           enum power_supply_property psp,
+                           union power_supply_propval *val)
+{
+       struct max17042_chip *chip = power_supply_get_drvdata(psy);
+       struct regmap *map = chip->regmap;
+       int ret;
+       u32 data;
+
+       if (!chip->init_complete)
+               return -EAGAIN;
+
+       switch (psp) {
+       case POWER_SUPPLY_PROP_PRESENT:
+               ret = regmap_read(map, MAX17042_STATUS, &data);
+               if (ret < 0)
+                       return ret;
+
+               if (data & MAX17042_STATUS_BattAbsent)
+                       val->intval = 0;
+               else
+                       val->intval = 1;
+               break;
+       case POWER_SUPPLY_PROP_CYCLE_COUNT:
+               ret = regmap_read(map, MAX17042_Cycles, &data);
+               if (ret < 0)
+                       return ret;
+
+               val->intval = data;
+               break;
+       case POWER_SUPPLY_PROP_VOLTAGE_MAX:
+               ret = regmap_read(map, MAX17042_MinMaxVolt, &data);
+               if (ret < 0)
+                       return ret;
+
+               val->intval = data >> 8;
+               val->intval *= 20000; /* Units of LSB = 20mV */
+               break;
+       case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
+               if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042)
+                       ret = regmap_read(map, MAX17042_V_empty, &data);
+               else
+                       ret = regmap_read(map, MAX17047_V_empty, &data);
+               if (ret < 0)
+                       return ret;
+
+               val->intval = data >> 7;
+               val->intval *= 10000; /* Units of LSB = 10mV */
+               break;
+       case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+               ret = regmap_read(map, MAX17042_VCELL, &data);
+               if (ret < 0)
+                       return ret;
+
+               val->intval = data * 625 / 8;
+               break;
+       case POWER_SUPPLY_PROP_VOLTAGE_AVG:
+               ret = regmap_read(map, MAX17042_AvgVCELL, &data);
+               if (ret < 0)
+                       return ret;
+
+               val->intval = data * 625 / 8;
+               break;
+       case POWER_SUPPLY_PROP_VOLTAGE_OCV:
+               ret = regmap_read(map, MAX17042_OCVInternal, &data);
+               if (ret < 0)
+                       return ret;
+
+               val->intval = data * 625 / 8;
+               break;
+       case POWER_SUPPLY_PROP_CAPACITY:
+               ret = regmap_read(map, MAX17042_RepSOC, &data);
+               if (ret < 0)
+                       return ret;
+
+               val->intval = data >> 8;
+               break;
+       case POWER_SUPPLY_PROP_CHARGE_FULL:
+               ret = regmap_read(map, MAX17042_FullCAP, &data);
+               if (ret < 0)
+                       return ret;
+
+               val->intval = data * 1000 / 2;
+               break;
+       case POWER_SUPPLY_PROP_CHARGE_COUNTER:
+               ret = regmap_read(map, MAX17042_QH, &data);
+               if (ret < 0)
+                       return ret;
+
+               val->intval = data * 1000 / 2;
+               break;
+       case POWER_SUPPLY_PROP_TEMP:
+               ret = regmap_read(map, MAX17042_TEMP, &data);
+               if (ret < 0)
+                       return ret;
+
+               val->intval = data;
+               /* The value is signed. */
+               if (val->intval & 0x8000) {
+                       val->intval = (0x7fff & ~val->intval) + 1;
+                       val->intval *= -1;
+               }
+               /* The value is converted into deci-centigrade scale */
+               /* Units of LSB = 1 / 256 degree Celsius */
+               val->intval = val->intval * 10 / 256;
+               break;
+       case POWER_SUPPLY_PROP_CURRENT_NOW:
+               if (chip->pdata->enable_current_sense) {
+                       ret = regmap_read(map, MAX17042_Current, &data);
+                       if (ret < 0)
+                               return ret;
+
+                       val->intval = data;
+                       if (val->intval & 0x8000) {
+                               /* Negative */
+                               val->intval = ~val->intval & 0x7fff;
+                               val->intval++;
+                               val->intval *= -1;
+                       }
+                       val->intval *= 1562500 / chip->pdata->r_sns;
+               } else {
+                       return -EINVAL;
+               }
+               break;
+       case POWER_SUPPLY_PROP_CURRENT_AVG:
+               if (chip->pdata->enable_current_sense) {
+                       ret = regmap_read(map, MAX17042_AvgCurrent, &data);
+                       if (ret < 0)
+                               return ret;
+
+                       val->intval = data;
+                       if (val->intval & 0x8000) {
+                               /* Negative */
+                               val->intval = ~val->intval & 0x7fff;
+                               val->intval++;
+                               val->intval *= -1;
+                       }
+                       val->intval *= 1562500 / chip->pdata->r_sns;
+               } else {
+                       return -EINVAL;
+               }
+               break;
+       default:
+               return -EINVAL;
+       }
+       return 0;
+}
+
+static int max17042_write_verify_reg(struct regmap *map, u8 reg, u32 value)
+{
+       int retries = 8;
+       int ret;
+       u32 read_value;
+
+       do {
+               ret = regmap_write(map, reg, value);
+               regmap_read(map, reg, &read_value);
+               if (read_value != value) {
+                       ret = -EIO;
+                       retries--;
+               }
+       } while (retries && read_value != value);
+
+       if (ret < 0)
+               pr_err("%s: err %d\n", __func__, ret);
+
+       return ret;
+}
+
+static inline void max17042_override_por(struct regmap *map,
+                                        u8 reg, u16 value)
+{
+       if (value)
+               regmap_write(map, reg, value);
+}
+
+static inline void max10742_unlock_model(struct max17042_chip *chip)
+{
+       struct regmap *map = chip->regmap;
+
+       regmap_write(map, MAX17042_MLOCKReg1, MODEL_UNLOCK1);
+       regmap_write(map, MAX17042_MLOCKReg2, MODEL_UNLOCK2);
+}
+
+static inline void max10742_lock_model(struct max17042_chip *chip)
+{
+       struct regmap *map = chip->regmap;
+
+       regmap_write(map, MAX17042_MLOCKReg1, MODEL_LOCK1);
+       regmap_write(map, MAX17042_MLOCKReg2, MODEL_LOCK2);
+}
+
+static inline void max17042_write_model_data(struct max17042_chip *chip,
+                                       u8 addr, int size)
+{
+       struct regmap *map = chip->regmap;
+       int i;
+
+       for (i = 0; i < size; i++)
+               regmap_write(map, addr + i,
+                       chip->pdata->config_data->cell_char_tbl[i]);
+}
+
+static inline void max17042_read_model_data(struct max17042_chip *chip,
+                                       u8 addr, u32 *data, int size)
+{
+       struct regmap *map = chip->regmap;
+       int i;
+
+       for (i = 0; i < size; i++)
+               regmap_read(map, addr + i, &data[i]);
+}
+
+static inline int max17042_model_data_compare(struct max17042_chip *chip,
+                                       u16 *data1, u16 *data2, int size)
+{
+       int i;
+
+       if (memcmp(data1, data2, size)) {
+               dev_err(&chip->client->dev, "%s compare failed\n", __func__);
+               for (i = 0; i < size; i++)
+                       dev_info(&chip->client->dev, "0x%x, 0x%x",
+                               data1[i], data2[i]);
+               dev_info(&chip->client->dev, "\n");
+               return -EINVAL;
+       }
+       return 0;
+}
+
+static int max17042_init_model(struct max17042_chip *chip)
+{
+       int ret;
+       int table_size = ARRAY_SIZE(chip->pdata->config_data->cell_char_tbl);
+       u32 *temp_data;
+
+       temp_data = kcalloc(table_size, sizeof(*temp_data), GFP_KERNEL);
+       if (!temp_data)
+               return -ENOMEM;
+
+       max10742_unlock_model(chip);
+       max17042_write_model_data(chip, MAX17042_MODELChrTbl,
+                               table_size);
+       max17042_read_model_data(chip, MAX17042_MODELChrTbl, temp_data,
+                               table_size);
+
+       ret = max17042_model_data_compare(
+               chip,
+               chip->pdata->config_data->cell_char_tbl,
+               (u16 *)temp_data,
+               table_size);
+
+       max10742_lock_model(chip);
+       kfree(temp_data);
+
+       return ret;
+}
+
+static int max17042_verify_model_lock(struct max17042_chip *chip)
+{
+       int i;
+       int table_size = ARRAY_SIZE(chip->pdata->config_data->cell_char_tbl);
+       u32 *temp_data;
+       int ret = 0;
+
+       temp_data = kcalloc(table_size, sizeof(*temp_data), GFP_KERNEL);
+       if (!temp_data)
+               return -ENOMEM;
+
+       max17042_read_model_data(chip, MAX17042_MODELChrTbl, temp_data,
+                               table_size);
+       for (i = 0; i < table_size; i++)
+               if (temp_data[i])
+                       ret = -EINVAL;
+
+       kfree(temp_data);
+       return ret;
+}
+
+static void max17042_write_config_regs(struct max17042_chip *chip)
+{
+       struct max17042_config_data *config = chip->pdata->config_data;
+       struct regmap *map = chip->regmap;
+
+       regmap_write(map, MAX17042_CONFIG, config->config);
+       regmap_write(map, MAX17042_LearnCFG, config->learn_cfg);
+       regmap_write(map, MAX17042_FilterCFG,
+                       config->filter_cfg);
+       regmap_write(map, MAX17042_RelaxCFG, config->relax_cfg);
+       if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17047 ||
+                       chip->chip_type == MAXIM_DEVICE_TYPE_MAX17050)
+               regmap_write(map, MAX17047_FullSOCThr,
+                                               config->full_soc_thresh);
+}
+
+static void  max17042_write_custom_regs(struct max17042_chip *chip)
+{
+       struct max17042_config_data *config = chip->pdata->config_data;
+       struct regmap *map = chip->regmap;
+
+       max17042_write_verify_reg(map, MAX17042_RCOMP0, config->rcomp0);
+       max17042_write_verify_reg(map, MAX17042_TempCo, config->tcompc0);
+       max17042_write_verify_reg(map, MAX17042_ICHGTerm, config->ichgt_term);
+       if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042) {
+               regmap_write(map, MAX17042_EmptyTempCo, config->empty_tempco);
+               max17042_write_verify_reg(map, MAX17042_K_empty0,
+                                       config->kempty0);
+       } else {
+               max17042_write_verify_reg(map, MAX17047_QRTbl00,
+                                               config->qrtbl00);
+               max17042_write_verify_reg(map, MAX17047_QRTbl10,
+                                               config->qrtbl10);
+               max17042_write_verify_reg(map, MAX17047_QRTbl20,
+                                               config->qrtbl20);
+               max17042_write_verify_reg(map, MAX17047_QRTbl30,
+                                               config->qrtbl30);
+       }
+}
+
+static void max17042_update_capacity_regs(struct max17042_chip *chip)
+{
+       struct max17042_config_data *config = chip->pdata->config_data;
+       struct regmap *map = chip->regmap;
+
+       max17042_write_verify_reg(map, MAX17042_FullCAP,
+                               config->fullcap);
+       regmap_write(map, MAX17042_DesignCap, config->design_cap);
+       max17042_write_verify_reg(map, MAX17042_FullCAPNom,
+                               config->fullcapnom);
+}
+
+static void max17042_reset_vfsoc0_reg(struct max17042_chip *chip)
+{
+       unsigned int vfSoc;
+       struct regmap *map = chip->regmap;
+
+       regmap_read(map, MAX17042_VFSOC, &vfSoc);
+       regmap_write(map, MAX17042_VFSOC0Enable, VFSOC0_UNLOCK);
+       max17042_write_verify_reg(map, MAX17042_VFSOC0, vfSoc);
+       regmap_write(map, MAX17042_VFSOC0Enable, VFSOC0_LOCK);
+}
+
+static void max17042_load_new_capacity_params(struct max17042_chip *chip)
+{
+       u32 full_cap0, rep_cap, dq_acc, vfSoc;
+       u32 rem_cap;
+
+       struct max17042_config_data *config = chip->pdata->config_data;
+       struct regmap *map = chip->regmap;
+
+       regmap_read(map, MAX17042_FullCAP0, &full_cap0);
+       regmap_read(map, MAX17042_VFSOC, &vfSoc);
+
+       /* fg_vfSoc needs to shifted by 8 bits to get the
+        * perc in 1% accuracy, to get the right rem_cap multiply
+        * full_cap0, fg_vfSoc and devide by 100
+        */
+       rem_cap = ((vfSoc >> 8) * full_cap0) / 100;
+       max17042_write_verify_reg(map, MAX17042_RemCap, rem_cap);
+
+       rep_cap = rem_cap;
+       max17042_write_verify_reg(map, MAX17042_RepCap, rep_cap);
+
+       /* Write dQ_acc to 200% of Capacity and dP_acc to 200% */
+       dq_acc = config->fullcap / dQ_ACC_DIV;
+       max17042_write_verify_reg(map, MAX17042_dQacc, dq_acc);
+       max17042_write_verify_reg(map, MAX17042_dPacc, dP_ACC_200);
+
+       max17042_write_verify_reg(map, MAX17042_FullCAP,
+                       config->fullcap);
+       regmap_write(map, MAX17042_DesignCap,
+                       config->design_cap);
+       max17042_write_verify_reg(map, MAX17042_FullCAPNom,
+                       config->fullcapnom);
+       /* Update SOC register with new SOC */
+       regmap_write(map, MAX17042_RepSOC, vfSoc);
+}
+
+/*
+ * Block write all the override values coming from platform data.
+ * This function MUST be called before the POR initialization proceedure
+ * specified by maxim.
+ */
+static inline void max17042_override_por_values(struct max17042_chip *chip)
+{
+       struct regmap *map = chip->regmap;
+       struct max17042_config_data *config = chip->pdata->config_data;
+
+       max17042_override_por(map, MAX17042_TGAIN, config->tgain);
+       max17042_override_por(map, MAx17042_TOFF, config->toff);
+       max17042_override_por(map, MAX17042_CGAIN, config->cgain);
+       max17042_override_por(map, MAX17042_COFF, config->coff);
+
+       max17042_override_por(map, MAX17042_VALRT_Th, config->valrt_thresh);
+       max17042_override_por(map, MAX17042_TALRT_Th, config->talrt_thresh);
+       max17042_override_por(map, MAX17042_SALRT_Th,
+                                               config->soc_alrt_thresh);
+       max17042_override_por(map, MAX17042_CONFIG, config->config);
+       max17042_override_por(map, MAX17042_SHDNTIMER, config->shdntimer);
+
+       max17042_override_por(map, MAX17042_DesignCap, config->design_cap);
+       max17042_override_por(map, MAX17042_ICHGTerm, config->ichgt_term);
+
+       max17042_override_por(map, MAX17042_AtRate, config->at_rate);
+       max17042_override_por(map, MAX17042_LearnCFG, config->learn_cfg);
+       max17042_override_por(map, MAX17042_FilterCFG, config->filter_cfg);
+       max17042_override_por(map, MAX17042_RelaxCFG, config->relax_cfg);
+       max17042_override_por(map, MAX17042_MiscCFG, config->misc_cfg);
+       max17042_override_por(map, MAX17042_MaskSOC, config->masksoc);
+
+       max17042_override_por(map, MAX17042_FullCAP, config->fullcap);
+       max17042_override_por(map, MAX17042_FullCAPNom, config->fullcapnom);
+       if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042)
+               max17042_override_por(map, MAX17042_SOC_empty,
+                                               config->socempty);
+       max17042_override_por(map, MAX17042_LAvg_empty, config->lavg_empty);
+       max17042_override_por(map, MAX17042_dQacc, config->dqacc);
+       max17042_override_por(map, MAX17042_dPacc, config->dpacc);
+
+       if (chip->chip_type == MAXIM_DEVICE_TYPE_MAX17042)
+               max17042_override_por(map, MAX17042_V_empty, config->vempty);
+       else
+               max17042_override_por(map, MAX17047_V_empty, config->vempty);
+       max17042_override_por(map, MAX17042_TempNom, config->temp_nom);
+       max17042_override_por(map, MAX17042_TempLim, config->temp_lim);
+       max17042_override_por(map, MAX17042_FCTC, config->fctc);
+       max17042_override_por(map, MAX17042_RCOMP0, config->rcomp0);
+       max17042_override_por(map, MAX17042_TempCo, config->tcompc0);
+       if (chip->chip_type) {
+               max17042_override_por(map, MAX17042_EmptyTempCo,
+                                               config->empty_tempco);
+               max17042_override_por(map, MAX17042_K_empty0,
+                                               config->kempty0);
+       }
+}
+
+static int max17042_init_chip(struct max17042_chip *chip)
+{
+       struct regmap *map = chip->regmap;
+       int ret;
+
+       max17042_override_por_values(chip);
+       /* After Power up, the MAX17042 requires 500mS in order
+        * to perform signal debouncing and initial SOC reporting
+        */
+       msleep(500);
+
+       /* Initialize configaration */
+       max17042_write_config_regs(chip);
+
+       /* write cell characterization data */
+       ret = max17042_init_model(chip);
+       if (ret) {
+               dev_err(&chip->client->dev, "%s init failed\n",
+                       __func__);
+               return -EIO;
+       }
+
+       ret = max17042_verify_model_lock(chip);
+       if (ret) {
+               dev_err(&chip->client->dev, "%s lock verify failed\n",
+                       __func__);
+               return -EIO;
+       }
+       /* write custom parameters */
+       max17042_write_custom_regs(chip);
+
+       /* update capacity params */
+       max17042_update_capacity_regs(chip);
+
+       /* delay must be atleast 350mS to allow VFSOC
+        * to be calculated from the new configuration
+        */
+       msleep(350);
+
+       /* reset vfsoc0 reg */
+       max17042_reset_vfsoc0_reg(chip);
+
+       /* load new capacity params */
+       max17042_load_new_capacity_params(chip);
+
+       /* Init complete, Clear the POR bit */
+       regmap_update_bits(map, MAX17042_STATUS, STATUS_POR_BIT, 0x0);
+       return 0;
+}
+
+static void max17042_set_soc_threshold(struct max17042_chip *chip, u16 off)
+{
+       struct regmap *map = chip->regmap;
+       u32 soc, soc_tr;
+
+       /* program interrupt thesholds such that we should
+        * get interrupt for every 'off' perc change in the soc
+        */
+       regmap_read(map, MAX17042_RepSOC, &soc);
+       soc >>= 8;
+       soc_tr = (soc + off) << 8;
+       soc_tr |= (soc - off);
+       regmap_write(map, MAX17042_SALRT_Th, soc_tr);
+}
+
+static irqreturn_t max17042_thread_handler(int id, void *dev)
+{
+       struct max17042_chip *chip = dev;
+       u32 val;
+
+       regmap_read(chip->regmap, MAX17042_STATUS, &val);
+       if ((val & STATUS_INTR_SOCMIN_BIT) ||
+               (val & STATUS_INTR_SOCMAX_BIT)) {
+               dev_info(&chip->client->dev, "SOC threshold INTR\n");
+               max17042_set_soc_threshold(chip, 1);
+       }
+
+       power_supply_changed(chip->battery);
+       return IRQ_HANDLED;
+}
+
+static void max17042_init_worker(struct work_struct *work)
+{
+       struct max17042_chip *chip = container_of(work,
+                               struct max17042_chip, work);
+       int ret;
+
+       /* Initialize registers according to values from the platform data */
+       if (chip->pdata->enable_por_init && chip->pdata->config_data) {
+               ret = max17042_init_chip(chip);
+               if (ret)
+                       return;
+       }
+
+       chip->init_complete = 1;
+}
+
+#ifdef CONFIG_OF
+static struct max17042_platform_data *
+max17042_get_pdata(struct device *dev)
+{
+       struct device_node *np = dev->of_node;
+       u32 prop;
+       struct max17042_platform_data *pdata;
+
+       if (!np)
+               return dev->platform_data;
+
+       pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+       if (!pdata)
+               return NULL;
+
+       /*
+        * Require current sense resistor value to be specified for
+        * current-sense functionality to be enabled at all.
+        */
+       if (of_property_read_u32(np, "maxim,rsns-microohm", &prop) == 0) {
+               pdata->r_sns = prop;
+               pdata->enable_current_sense = true;
+       }
+
+       return pdata;
+}
+#else
+static struct max17042_platform_data *
+max17042_get_pdata(struct device *dev)
+{
+       return dev->platform_data;
+}
+#endif
+
+static const struct regmap_config max17042_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 16,
+       .val_format_endian = REGMAP_ENDIAN_NATIVE,
+};
+
+static const struct power_supply_desc max17042_psy_desc = {
+       .name           = "max170xx_battery",
+       .type           = POWER_SUPPLY_TYPE_BATTERY,
+       .get_property   = max17042_get_property,
+       .properties     = max17042_battery_props,
+       .num_properties = ARRAY_SIZE(max17042_battery_props),
+};
+
+static const struct power_supply_desc max17042_no_current_sense_psy_desc = {
+       .name           = "max170xx_battery",
+       .type           = POWER_SUPPLY_TYPE_BATTERY,
+       .get_property   = max17042_get_property,
+       .properties     = max17042_battery_props,
+       .num_properties = ARRAY_SIZE(max17042_battery_props) - 2,
+};
+
+static int max17042_probe(struct i2c_client *client,
+                       const struct i2c_device_id *id)
+{
+       struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+       const struct power_supply_desc *max17042_desc = &max17042_psy_desc;
+       struct power_supply_config psy_cfg = {};
+       struct max17042_chip *chip;
+       int ret;
+       int i;
+       u32 val;
+
+       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
+               return -EIO;
+
+       chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
+       if (!chip)
+               return -ENOMEM;
+
+       chip->client = client;
+       chip->regmap = devm_regmap_init_i2c(client, &max17042_regmap_config);
+       if (IS_ERR(chip->regmap)) {
+               dev_err(&client->dev, "Failed to initialize regmap\n");
+               return -EINVAL;
+       }
+
+       chip->pdata = max17042_get_pdata(&client->dev);
+       if (!chip->pdata) {
+               dev_err(&client->dev, "no platform data provided\n");
+               return -EINVAL;
+       }
+
+       i2c_set_clientdata(client, chip);
+       chip->chip_type = id->driver_data;
+       psy_cfg.drv_data = chip;
+
+       /* When current is not measured,
+        * CURRENT_NOW and CURRENT_AVG properties should be invisible. */
+       if (!chip->pdata->enable_current_sense)
+               max17042_desc = &max17042_no_current_sense_psy_desc;
+
+       if (chip->pdata->r_sns == 0)
+               chip->pdata->r_sns = MAX17042_DEFAULT_SNS_RESISTOR;
+
+       if (chip->pdata->init_data)
+               for (i = 0; i < chip->pdata->num_init_data; i++)
+                       regmap_write(chip->regmap,
+                                       chip->pdata->init_data[i].addr,
+                                       chip->pdata->init_data[i].data);
+
+       if (!chip->pdata->enable_current_sense) {
+               regmap_write(chip->regmap, MAX17042_CGAIN, 0x0000);
+               regmap_write(chip->regmap, MAX17042_MiscCFG, 0x0003);
+               regmap_write(chip->regmap, MAX17042_LearnCFG, 0x0007);
+       }
+
+       chip->battery = power_supply_register(&client->dev, max17042_desc,
+                                               &psy_cfg);
+       if (IS_ERR(chip->battery)) {
+               dev_err(&client->dev, "failed: power supply register\n");
+               return PTR_ERR(chip->battery);
+       }
+
+       if (client->irq) {
+               ret = request_threaded_irq(client->irq, NULL,
+                                       max17042_thread_handler,
+                                       IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+                                       chip->battery->desc->name, chip);
+               if (!ret) {
+                       regmap_update_bits(chip->regmap, MAX17042_CONFIG,
+                                       CONFIG_ALRT_BIT_ENBL,
+                                       CONFIG_ALRT_BIT_ENBL);
+                       max17042_set_soc_threshold(chip, 1);
+               } else {
+                       client->irq = 0;
+                       dev_err(&client->dev, "%s(): cannot get IRQ\n",
+                               __func__);
+               }
+       }
+
+       regmap_read(chip->regmap, MAX17042_STATUS, &val);
+       if (val & STATUS_POR_BIT) {
+               INIT_WORK(&chip->work, max17042_init_worker);
+               schedule_work(&chip->work);
+       } else {
+               chip->init_complete = 1;
+       }
+
+       return 0;
+}
+
+static int max17042_remove(struct i2c_client *client)
+{
+       struct max17042_chip *chip = i2c_get_clientdata(client);
+
+       if (client->irq)
+               free_irq(client->irq, chip);
+       power_supply_unregister(chip->battery);
+       return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int max17042_suspend(struct device *dev)
+{
+       struct max17042_chip *chip = dev_get_drvdata(dev);
+
+       /*
+        * disable the irq and enable irq_wake
+        * capability to the interrupt line.
+        */
+       if (chip->client->irq) {
+               disable_irq(chip->client->irq);
+               enable_irq_wake(chip->client->irq);
+       }
+
+       return 0;
+}
+
+static int max17042_resume(struct device *dev)
+{
+       struct max17042_chip *chip = dev_get_drvdata(dev);
+
+       if (chip->client->irq) {
+               disable_irq_wake(chip->client->irq);
+               enable_irq(chip->client->irq);
+               /* re-program the SOC thresholds to 1% change */
+               max17042_set_soc_threshold(chip, 1);
+       }
+
+       return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(max17042_pm_ops, max17042_suspend,
+                       max17042_resume);
+
+#ifdef CONFIG_OF
+static const struct of_device_id max17042_dt_match[] = {
+       { .compatible = "maxim,max17042" },
+       { .compatible = "maxim,max17047" },
+       { .compatible = "maxim,max17050" },
+       { },
+};
+MODULE_DEVICE_TABLE(of, max17042_dt_match);
+#endif
+
+static const struct i2c_device_id max17042_id[] = {
+       { "max17042", MAXIM_DEVICE_TYPE_MAX17042 },
+       { "max17047", MAXIM_DEVICE_TYPE_MAX17047 },
+       { "max17050", MAXIM_DEVICE_TYPE_MAX17050 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, max17042_id);
+
+static struct i2c_driver max17042_i2c_driver = {
+       .driver = {
+               .name   = "max17042",
+               .of_match_table = of_match_ptr(max17042_dt_match),
+               .pm     = &max17042_pm_ops,
+       },
+       .probe          = max17042_probe,
+       .remove         = max17042_remove,
+       .id_table       = max17042_id,
+};
+module_i2c_driver(max17042_i2c_driver);
+
+MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
+MODULE_DESCRIPTION("MAX17042 Fuel Gauge");
+MODULE_LICENSE("GPL");