Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / power / ds2780_battery.c
diff --git a/kernel/drivers/power/ds2780_battery.c b/kernel/drivers/power/ds2780_battery.c
new file mode 100644 (file)
index 0000000..a7a0427
--- /dev/null
@@ -0,0 +1,854 @@
+/*
+ * 1-wire client/driver for the Maxim/Dallas DS2780 Stand-Alone Fuel Gauge IC
+ *
+ * Copyright (C) 2010 Indesign, LLC
+ *
+ * Author: Clifton Barnes <cabarnes@indesign-llc.com>
+ *
+ * Based on ds2760_battery and ds2782_battery drivers
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/param.h>
+#include <linux/pm.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/idr.h>
+
+#include "../w1/w1.h"
+#include "../w1/slaves/w1_ds2780.h"
+
+/* Current unit measurement in uA for a 1 milli-ohm sense resistor */
+#define DS2780_CURRENT_UNITS   1563
+/* Charge unit measurement in uAh for a 1 milli-ohm sense resistor */
+#define DS2780_CHARGE_UNITS            6250
+/* Number of bytes in user EEPROM space */
+#define DS2780_USER_EEPROM_SIZE                (DS2780_EEPROM_BLOCK0_END - \
+                                       DS2780_EEPROM_BLOCK0_START + 1)
+/* Number of bytes in parameter EEPROM space */
+#define DS2780_PARAM_EEPROM_SIZE       (DS2780_EEPROM_BLOCK1_END - \
+                                       DS2780_EEPROM_BLOCK1_START + 1)
+
+struct ds2780_device_info {
+       struct device *dev;
+       struct power_supply *bat;
+       struct power_supply_desc bat_desc;
+       struct device *w1_dev;
+};
+
+enum current_types {
+       CURRENT_NOW,
+       CURRENT_AVG,
+};
+
+static const char model[] = "DS2780";
+static const char manufacturer[] = "Maxim/Dallas";
+
+static inline struct ds2780_device_info *
+to_ds2780_device_info(struct power_supply *psy)
+{
+       return power_supply_get_drvdata(psy);
+}
+
+static inline struct power_supply *to_power_supply(struct device *dev)
+{
+       return dev_get_drvdata(dev);
+}
+
+static inline int ds2780_battery_io(struct ds2780_device_info *dev_info,
+       char *buf, int addr, size_t count, int io)
+{
+       return w1_ds2780_io(dev_info->w1_dev, buf, addr, count, io);
+}
+
+static inline int ds2780_read8(struct ds2780_device_info *dev_info, u8 *val,
+       int addr)
+{
+       return ds2780_battery_io(dev_info, val, addr, sizeof(u8), 0);
+}
+
+static int ds2780_read16(struct ds2780_device_info *dev_info, s16 *val,
+       int addr)
+{
+       int ret;
+       u8 raw[2];
+
+       ret = ds2780_battery_io(dev_info, raw, addr, sizeof(raw), 0);
+       if (ret < 0)
+               return ret;
+
+       *val = (raw[0] << 8) | raw[1];
+
+       return 0;
+}
+
+static inline int ds2780_read_block(struct ds2780_device_info *dev_info,
+       u8 *val, int addr, size_t count)
+{
+       return ds2780_battery_io(dev_info, val, addr, count, 0);
+}
+
+static inline int ds2780_write(struct ds2780_device_info *dev_info, u8 *val,
+       int addr, size_t count)
+{
+       return ds2780_battery_io(dev_info, val, addr, count, 1);
+}
+
+static inline int ds2780_store_eeprom(struct device *dev, int addr)
+{
+       return w1_ds2780_eeprom_cmd(dev, addr, W1_DS2780_COPY_DATA);
+}
+
+static inline int ds2780_recall_eeprom(struct device *dev, int addr)
+{
+       return w1_ds2780_eeprom_cmd(dev, addr, W1_DS2780_RECALL_DATA);
+}
+
+static int ds2780_save_eeprom(struct ds2780_device_info *dev_info, int reg)
+{
+       int ret;
+
+       ret = ds2780_store_eeprom(dev_info->w1_dev, reg);
+       if (ret < 0)
+               return ret;
+
+       ret = ds2780_recall_eeprom(dev_info->w1_dev, reg);
+       if (ret < 0)
+               return ret;
+
+       return 0;
+}
+
+/* Set sense resistor value in mhos */
+static int ds2780_set_sense_register(struct ds2780_device_info *dev_info,
+       u8 conductance)
+{
+       int ret;
+
+       ret = ds2780_write(dev_info, &conductance,
+                               DS2780_RSNSP_REG, sizeof(u8));
+       if (ret < 0)
+               return ret;
+
+       return ds2780_save_eeprom(dev_info, DS2780_RSNSP_REG);
+}
+
+/* Get RSGAIN value from 0 to 1.999 in steps of 0.001 */
+static int ds2780_get_rsgain_register(struct ds2780_device_info *dev_info,
+       u16 *rsgain)
+{
+       return ds2780_read16(dev_info, rsgain, DS2780_RSGAIN_MSB_REG);
+}
+
+/* Set RSGAIN value from 0 to 1.999 in steps of 0.001 */
+static int ds2780_set_rsgain_register(struct ds2780_device_info *dev_info,
+       u16 rsgain)
+{
+       int ret;
+       u8 raw[] = {rsgain >> 8, rsgain & 0xFF};
+
+       ret = ds2780_write(dev_info, raw,
+                               DS2780_RSGAIN_MSB_REG, sizeof(raw));
+       if (ret < 0)
+               return ret;
+
+       return ds2780_save_eeprom(dev_info, DS2780_RSGAIN_MSB_REG);
+}
+
+static int ds2780_get_voltage(struct ds2780_device_info *dev_info,
+       int *voltage_uV)
+{
+       int ret;
+       s16 voltage_raw;
+
+       /*
+        * The voltage value is located in 10 bits across the voltage MSB
+        * and LSB registers in two's compliment form
+        * Sign bit of the voltage value is in bit 7 of the voltage MSB register
+        * Bits 9 - 3 of the voltage value are in bits 6 - 0 of the
+        * voltage MSB register
+        * Bits 2 - 0 of the voltage value are in bits 7 - 5 of the
+        * voltage LSB register
+        */
+       ret = ds2780_read16(dev_info, &voltage_raw,
+                               DS2780_VOLT_MSB_REG);
+       if (ret < 0)
+               return ret;
+
+       /*
+        * DS2780 reports voltage in units of 4.88mV, but the battery class
+        * reports in units of uV, so convert by multiplying by 4880.
+        */
+       *voltage_uV = (voltage_raw / 32) * 4880;
+       return 0;
+}
+
+static int ds2780_get_temperature(struct ds2780_device_info *dev_info,
+       int *temperature)
+{
+       int ret;
+       s16 temperature_raw;
+
+       /*
+        * The temperature value is located in 10 bits across the temperature
+        * MSB and LSB registers in two's compliment form
+        * Sign bit of the temperature value is in bit 7 of the temperature
+        * MSB register
+        * Bits 9 - 3 of the temperature value are in bits 6 - 0 of the
+        * temperature MSB register
+        * Bits 2 - 0 of the temperature value are in bits 7 - 5 of the
+        * temperature LSB register
+        */
+       ret = ds2780_read16(dev_info, &temperature_raw,
+                               DS2780_TEMP_MSB_REG);
+       if (ret < 0)
+               return ret;
+
+       /*
+        * Temperature is measured in units of 0.125 degrees celcius, the
+        * power_supply class measures temperature in tenths of degrees
+        * celsius. The temperature value is stored as a 10 bit number, plus
+        * sign in the upper bits of a 16 bit register.
+        */
+       *temperature = ((temperature_raw / 32) * 125) / 100;
+       return 0;
+}
+
+static int ds2780_get_current(struct ds2780_device_info *dev_info,
+       enum current_types type, int *current_uA)
+{
+       int ret, sense_res;
+       s16 current_raw;
+       u8 sense_res_raw, reg_msb;
+
+       /*
+        * The units of measurement for current are dependent on the value of
+        * the sense resistor.
+        */
+       ret = ds2780_read8(dev_info, &sense_res_raw, DS2780_RSNSP_REG);
+       if (ret < 0)
+               return ret;
+
+       if (sense_res_raw == 0) {
+               dev_err(dev_info->dev, "sense resistor value is 0\n");
+               return -EINVAL;
+       }
+       sense_res = 1000 / sense_res_raw;
+
+       if (type == CURRENT_NOW)
+               reg_msb = DS2780_CURRENT_MSB_REG;
+       else if (type == CURRENT_AVG)
+               reg_msb = DS2780_IAVG_MSB_REG;
+       else
+               return -EINVAL;
+
+       /*
+        * The current value is located in 16 bits across the current MSB
+        * and LSB registers in two's compliment form
+        * Sign bit of the current value is in bit 7 of the current MSB register
+        * Bits 14 - 8 of the current value are in bits 6 - 0 of the current
+        * MSB register
+        * Bits 7 - 0 of the current value are in bits 7 - 0 of the current
+        * LSB register
+        */
+       ret = ds2780_read16(dev_info, &current_raw, reg_msb);
+       if (ret < 0)
+               return ret;
+
+       *current_uA = current_raw * (DS2780_CURRENT_UNITS / sense_res);
+       return 0;
+}
+
+static int ds2780_get_accumulated_current(struct ds2780_device_info *dev_info,
+       int *accumulated_current)
+{
+       int ret, sense_res;
+       s16 current_raw;
+       u8 sense_res_raw;
+
+       /*
+        * The units of measurement for accumulated current are dependent on
+        * the value of the sense resistor.
+        */
+       ret = ds2780_read8(dev_info, &sense_res_raw, DS2780_RSNSP_REG);
+       if (ret < 0)
+               return ret;
+
+       if (sense_res_raw == 0) {
+               dev_err(dev_info->dev, "sense resistor value is 0\n");
+               return -ENXIO;
+       }
+       sense_res = 1000 / sense_res_raw;
+
+       /*
+        * The ACR value is located in 16 bits across the ACR MSB and
+        * LSB registers
+        * Bits 15 - 8 of the ACR value are in bits 7 - 0 of the ACR
+        * MSB register
+        * Bits 7 - 0 of the ACR value are in bits 7 - 0 of the ACR
+        * LSB register
+        */
+       ret = ds2780_read16(dev_info, &current_raw, DS2780_ACR_MSB_REG);
+       if (ret < 0)
+               return ret;
+
+       *accumulated_current = current_raw * (DS2780_CHARGE_UNITS / sense_res);
+       return 0;
+}
+
+static int ds2780_get_capacity(struct ds2780_device_info *dev_info,
+       int *capacity)
+{
+       int ret;
+       u8 raw;
+
+       ret = ds2780_read8(dev_info, &raw, DS2780_RARC_REG);
+       if (ret < 0)
+               return ret;
+
+       *capacity = raw;
+       return raw;
+}
+
+static int ds2780_get_status(struct ds2780_device_info *dev_info, int *status)
+{
+       int ret, current_uA, capacity;
+
+       ret = ds2780_get_current(dev_info, CURRENT_NOW, &current_uA);
+       if (ret < 0)
+               return ret;
+
+       ret = ds2780_get_capacity(dev_info, &capacity);
+       if (ret < 0)
+               return ret;
+
+       if (capacity == 100)
+               *status = POWER_SUPPLY_STATUS_FULL;
+       else if (current_uA == 0)
+               *status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+       else if (current_uA < 0)
+               *status = POWER_SUPPLY_STATUS_DISCHARGING;
+       else
+               *status = POWER_SUPPLY_STATUS_CHARGING;
+
+       return 0;
+}
+
+static int ds2780_get_charge_now(struct ds2780_device_info *dev_info,
+       int *charge_now)
+{
+       int ret;
+       u16 charge_raw;
+
+       /*
+        * The RAAC value is located in 16 bits across the RAAC MSB and
+        * LSB registers
+        * Bits 15 - 8 of the RAAC value are in bits 7 - 0 of the RAAC
+        * MSB register
+        * Bits 7 - 0 of the RAAC value are in bits 7 - 0 of the RAAC
+        * LSB register
+        */
+       ret = ds2780_read16(dev_info, &charge_raw, DS2780_RAAC_MSB_REG);
+       if (ret < 0)
+               return ret;
+
+       *charge_now = charge_raw * 1600;
+       return 0;
+}
+
+static int ds2780_get_control_register(struct ds2780_device_info *dev_info,
+       u8 *control_reg)
+{
+       return ds2780_read8(dev_info, control_reg, DS2780_CONTROL_REG);
+}
+
+static int ds2780_set_control_register(struct ds2780_device_info *dev_info,
+       u8 control_reg)
+{
+       int ret;
+
+       ret = ds2780_write(dev_info, &control_reg,
+                               DS2780_CONTROL_REG, sizeof(u8));
+       if (ret < 0)
+               return ret;
+
+       return ds2780_save_eeprom(dev_info, DS2780_CONTROL_REG);
+}
+
+static int ds2780_battery_get_property(struct power_supply *psy,
+       enum power_supply_property psp,
+       union power_supply_propval *val)
+{
+       int ret = 0;
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+
+       switch (psp) {
+       case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+               ret = ds2780_get_voltage(dev_info, &val->intval);
+               break;
+
+       case POWER_SUPPLY_PROP_TEMP:
+               ret = ds2780_get_temperature(dev_info, &val->intval);
+               break;
+
+       case POWER_SUPPLY_PROP_MODEL_NAME:
+               val->strval = model;
+               break;
+
+       case POWER_SUPPLY_PROP_MANUFACTURER:
+               val->strval = manufacturer;
+               break;
+
+       case POWER_SUPPLY_PROP_CURRENT_NOW:
+               ret = ds2780_get_current(dev_info, CURRENT_NOW, &val->intval);
+               break;
+
+       case POWER_SUPPLY_PROP_CURRENT_AVG:
+               ret = ds2780_get_current(dev_info, CURRENT_AVG, &val->intval);
+               break;
+
+       case POWER_SUPPLY_PROP_STATUS:
+               ret = ds2780_get_status(dev_info, &val->intval);
+               break;
+
+       case POWER_SUPPLY_PROP_CAPACITY:
+               ret = ds2780_get_capacity(dev_info, &val->intval);
+               break;
+
+       case POWER_SUPPLY_PROP_CHARGE_COUNTER:
+               ret = ds2780_get_accumulated_current(dev_info, &val->intval);
+               break;
+
+       case POWER_SUPPLY_PROP_CHARGE_NOW:
+               ret = ds2780_get_charge_now(dev_info, &val->intval);
+               break;
+
+       default:
+               ret = -EINVAL;
+       }
+
+       return ret;
+}
+
+static enum power_supply_property ds2780_battery_props[] = {
+       POWER_SUPPLY_PROP_STATUS,
+       POWER_SUPPLY_PROP_VOLTAGE_NOW,
+       POWER_SUPPLY_PROP_TEMP,
+       POWER_SUPPLY_PROP_MODEL_NAME,
+       POWER_SUPPLY_PROP_MANUFACTURER,
+       POWER_SUPPLY_PROP_CURRENT_NOW,
+       POWER_SUPPLY_PROP_CURRENT_AVG,
+       POWER_SUPPLY_PROP_CAPACITY,
+       POWER_SUPPLY_PROP_CHARGE_COUNTER,
+       POWER_SUPPLY_PROP_CHARGE_NOW,
+};
+
+static ssize_t ds2780_get_pmod_enabled(struct device *dev,
+       struct device_attribute *attr,
+       char *buf)
+{
+       int ret;
+       u8 control_reg;
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+
+       /* Get power mode */
+       ret = ds2780_get_control_register(dev_info, &control_reg);
+       if (ret < 0)
+               return ret;
+
+       return sprintf(buf, "%d\n",
+                !!(control_reg & DS2780_CONTROL_REG_PMOD));
+}
+
+static ssize_t ds2780_set_pmod_enabled(struct device *dev,
+       struct device_attribute *attr,
+       const char *buf,
+       size_t count)
+{
+       int ret;
+       u8 control_reg, new_setting;
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+
+       /* Set power mode */
+       ret = ds2780_get_control_register(dev_info, &control_reg);
+       if (ret < 0)
+               return ret;
+
+       ret = kstrtou8(buf, 0, &new_setting);
+       if (ret < 0)
+               return ret;
+
+       if ((new_setting != 0) && (new_setting != 1)) {
+               dev_err(dev_info->dev, "Invalid pmod setting (0 or 1)\n");
+               return -EINVAL;
+       }
+
+       if (new_setting)
+               control_reg |= DS2780_CONTROL_REG_PMOD;
+       else
+               control_reg &= ~DS2780_CONTROL_REG_PMOD;
+
+       ret = ds2780_set_control_register(dev_info, control_reg);
+       if (ret < 0)
+               return ret;
+
+       return count;
+}
+
+static ssize_t ds2780_get_sense_resistor_value(struct device *dev,
+       struct device_attribute *attr,
+       char *buf)
+{
+       int ret;
+       u8 sense_resistor;
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+
+       ret = ds2780_read8(dev_info, &sense_resistor, DS2780_RSNSP_REG);
+       if (ret < 0)
+               return ret;
+
+       ret = sprintf(buf, "%d\n", sense_resistor);
+       return ret;
+}
+
+static ssize_t ds2780_set_sense_resistor_value(struct device *dev,
+       struct device_attribute *attr,
+       const char *buf,
+       size_t count)
+{
+       int ret;
+       u8 new_setting;
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+
+       ret = kstrtou8(buf, 0, &new_setting);
+       if (ret < 0)
+               return ret;
+
+       ret = ds2780_set_sense_register(dev_info, new_setting);
+       if (ret < 0)
+               return ret;
+
+       return count;
+}
+
+static ssize_t ds2780_get_rsgain_setting(struct device *dev,
+       struct device_attribute *attr,
+       char *buf)
+{
+       int ret;
+       u16 rsgain;
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+
+       ret = ds2780_get_rsgain_register(dev_info, &rsgain);
+       if (ret < 0)
+               return ret;
+
+       return sprintf(buf, "%d\n", rsgain);
+}
+
+static ssize_t ds2780_set_rsgain_setting(struct device *dev,
+       struct device_attribute *attr,
+       const char *buf,
+       size_t count)
+{
+       int ret;
+       u16 new_setting;
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+
+       ret = kstrtou16(buf, 0, &new_setting);
+       if (ret < 0)
+               return ret;
+
+       /* Gain can only be from 0 to 1.999 in steps of .001 */
+       if (new_setting > 1999) {
+               dev_err(dev_info->dev, "Invalid rsgain setting (0 - 1999)\n");
+               return -EINVAL;
+       }
+
+       ret = ds2780_set_rsgain_register(dev_info, new_setting);
+       if (ret < 0)
+               return ret;
+
+       return count;
+}
+
+static ssize_t ds2780_get_pio_pin(struct device *dev,
+       struct device_attribute *attr,
+       char *buf)
+{
+       int ret;
+       u8 sfr;
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+
+       ret = ds2780_read8(dev_info, &sfr, DS2780_SFR_REG);
+       if (ret < 0)
+               return ret;
+
+       ret = sprintf(buf, "%d\n", sfr & DS2780_SFR_REG_PIOSC);
+       return ret;
+}
+
+static ssize_t ds2780_set_pio_pin(struct device *dev,
+       struct device_attribute *attr,
+       const char *buf,
+       size_t count)
+{
+       int ret;
+       u8 new_setting;
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+
+       ret = kstrtou8(buf, 0, &new_setting);
+       if (ret < 0)
+               return ret;
+
+       if ((new_setting != 0) && (new_setting != 1)) {
+               dev_err(dev_info->dev, "Invalid pio_pin setting (0 or 1)\n");
+               return -EINVAL;
+       }
+
+       ret = ds2780_write(dev_info, &new_setting,
+                               DS2780_SFR_REG, sizeof(u8));
+       if (ret < 0)
+               return ret;
+
+       return count;
+}
+
+static ssize_t ds2780_read_param_eeprom_bin(struct file *filp,
+                               struct kobject *kobj,
+                               struct bin_attribute *bin_attr,
+                               char *buf, loff_t off, size_t count)
+{
+       struct device *dev = container_of(kobj, struct device, kobj);
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+
+       count = min_t(loff_t, count,
+               DS2780_EEPROM_BLOCK1_END -
+               DS2780_EEPROM_BLOCK1_START + 1 - off);
+
+       return ds2780_read_block(dev_info, buf,
+                               DS2780_EEPROM_BLOCK1_START + off, count);
+}
+
+static ssize_t ds2780_write_param_eeprom_bin(struct file *filp,
+                               struct kobject *kobj,
+                               struct bin_attribute *bin_attr,
+                               char *buf, loff_t off, size_t count)
+{
+       struct device *dev = container_of(kobj, struct device, kobj);
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+       int ret;
+
+       count = min_t(loff_t, count,
+               DS2780_EEPROM_BLOCK1_END -
+               DS2780_EEPROM_BLOCK1_START + 1 - off);
+
+       ret = ds2780_write(dev_info, buf,
+                               DS2780_EEPROM_BLOCK1_START + off, count);
+       if (ret < 0)
+               return ret;
+
+       ret = ds2780_save_eeprom(dev_info, DS2780_EEPROM_BLOCK1_START);
+       if (ret < 0)
+               return ret;
+
+       return count;
+}
+
+static struct bin_attribute ds2780_param_eeprom_bin_attr = {
+       .attr = {
+               .name = "param_eeprom",
+               .mode = S_IRUGO | S_IWUSR,
+       },
+       .size = DS2780_EEPROM_BLOCK1_END - DS2780_EEPROM_BLOCK1_START + 1,
+       .read = ds2780_read_param_eeprom_bin,
+       .write = ds2780_write_param_eeprom_bin,
+};
+
+static ssize_t ds2780_read_user_eeprom_bin(struct file *filp,
+                               struct kobject *kobj,
+                               struct bin_attribute *bin_attr,
+                               char *buf, loff_t off, size_t count)
+{
+       struct device *dev = container_of(kobj, struct device, kobj);
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+
+       count = min_t(loff_t, count,
+               DS2780_EEPROM_BLOCK0_END -
+               DS2780_EEPROM_BLOCK0_START + 1 - off);
+
+       return ds2780_read_block(dev_info, buf,
+                               DS2780_EEPROM_BLOCK0_START + off, count);
+}
+
+static ssize_t ds2780_write_user_eeprom_bin(struct file *filp,
+                               struct kobject *kobj,
+                               struct bin_attribute *bin_attr,
+                               char *buf, loff_t off, size_t count)
+{
+       struct device *dev = container_of(kobj, struct device, kobj);
+       struct power_supply *psy = to_power_supply(dev);
+       struct ds2780_device_info *dev_info = to_ds2780_device_info(psy);
+       int ret;
+
+       count = min_t(loff_t, count,
+               DS2780_EEPROM_BLOCK0_END -
+               DS2780_EEPROM_BLOCK0_START + 1 - off);
+
+       ret = ds2780_write(dev_info, buf,
+                               DS2780_EEPROM_BLOCK0_START + off, count);
+       if (ret < 0)
+               return ret;
+
+       ret = ds2780_save_eeprom(dev_info, DS2780_EEPROM_BLOCK0_START);
+       if (ret < 0)
+               return ret;
+
+       return count;
+}
+
+static struct bin_attribute ds2780_user_eeprom_bin_attr = {
+       .attr = {
+               .name = "user_eeprom",
+               .mode = S_IRUGO | S_IWUSR,
+       },
+       .size = DS2780_EEPROM_BLOCK0_END - DS2780_EEPROM_BLOCK0_START + 1,
+       .read = ds2780_read_user_eeprom_bin,
+       .write = ds2780_write_user_eeprom_bin,
+};
+
+static DEVICE_ATTR(pmod_enabled, S_IRUGO | S_IWUSR, ds2780_get_pmod_enabled,
+       ds2780_set_pmod_enabled);
+static DEVICE_ATTR(sense_resistor_value, S_IRUGO | S_IWUSR,
+       ds2780_get_sense_resistor_value, ds2780_set_sense_resistor_value);
+static DEVICE_ATTR(rsgain_setting, S_IRUGO | S_IWUSR, ds2780_get_rsgain_setting,
+       ds2780_set_rsgain_setting);
+static DEVICE_ATTR(pio_pin, S_IRUGO | S_IWUSR, ds2780_get_pio_pin,
+       ds2780_set_pio_pin);
+
+
+static struct attribute *ds2780_attributes[] = {
+       &dev_attr_pmod_enabled.attr,
+       &dev_attr_sense_resistor_value.attr,
+       &dev_attr_rsgain_setting.attr,
+       &dev_attr_pio_pin.attr,
+       NULL
+};
+
+static const struct attribute_group ds2780_attr_group = {
+       .attrs = ds2780_attributes,
+};
+
+static int ds2780_battery_probe(struct platform_device *pdev)
+{
+       struct power_supply_config psy_cfg = {};
+       int ret = 0;
+       struct ds2780_device_info *dev_info;
+
+       dev_info = devm_kzalloc(&pdev->dev, sizeof(*dev_info), GFP_KERNEL);
+       if (!dev_info) {
+               ret = -ENOMEM;
+               goto fail;
+       }
+
+       platform_set_drvdata(pdev, dev_info);
+
+       dev_info->dev                   = &pdev->dev;
+       dev_info->w1_dev                = pdev->dev.parent;
+       dev_info->bat_desc.name         = dev_name(&pdev->dev);
+       dev_info->bat_desc.type         = POWER_SUPPLY_TYPE_BATTERY;
+       dev_info->bat_desc.properties   = ds2780_battery_props;
+       dev_info->bat_desc.num_properties = ARRAY_SIZE(ds2780_battery_props);
+       dev_info->bat_desc.get_property = ds2780_battery_get_property;
+
+       psy_cfg.drv_data                = dev_info;
+
+       dev_info->bat = power_supply_register(&pdev->dev, &dev_info->bat_desc,
+                                             &psy_cfg);
+       if (IS_ERR(dev_info->bat)) {
+               dev_err(dev_info->dev, "failed to register battery\n");
+               ret = PTR_ERR(dev_info->bat);
+               goto fail;
+       }
+
+       ret = sysfs_create_group(&dev_info->bat->dev.kobj, &ds2780_attr_group);
+       if (ret) {
+               dev_err(dev_info->dev, "failed to create sysfs group\n");
+               goto fail_unregister;
+       }
+
+       ret = sysfs_create_bin_file(&dev_info->bat->dev.kobj,
+                                       &ds2780_param_eeprom_bin_attr);
+       if (ret) {
+               dev_err(dev_info->dev,
+                               "failed to create param eeprom bin file");
+               goto fail_remove_group;
+       }
+
+       ret = sysfs_create_bin_file(&dev_info->bat->dev.kobj,
+                                       &ds2780_user_eeprom_bin_attr);
+       if (ret) {
+               dev_err(dev_info->dev,
+                               "failed to create user eeprom bin file");
+               goto fail_remove_bin_file;
+       }
+
+       return 0;
+
+fail_remove_bin_file:
+       sysfs_remove_bin_file(&dev_info->bat->dev.kobj,
+                               &ds2780_param_eeprom_bin_attr);
+fail_remove_group:
+       sysfs_remove_group(&dev_info->bat->dev.kobj, &ds2780_attr_group);
+fail_unregister:
+       power_supply_unregister(dev_info->bat);
+fail:
+       return ret;
+}
+
+static int ds2780_battery_remove(struct platform_device *pdev)
+{
+       struct ds2780_device_info *dev_info = platform_get_drvdata(pdev);
+
+       /*
+        * Remove attributes before unregistering power supply
+        * because 'bat' will be freed on power_supply_unregister() call.
+        */
+       sysfs_remove_group(&dev_info->bat->dev.kobj, &ds2780_attr_group);
+
+       power_supply_unregister(dev_info->bat);
+
+       return 0;
+}
+
+static struct platform_driver ds2780_battery_driver = {
+       .driver = {
+               .name = "ds2780-battery",
+       },
+       .probe    = ds2780_battery_probe,
+       .remove   = ds2780_battery_remove,
+};
+
+module_platform_driver(ds2780_battery_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Clifton Barnes <cabarnes@indesign-llc.com>");
+MODULE_DESCRIPTION("Maxim/Dallas DS2780 Stand-Alone Fuel Gauage IC driver");
+MODULE_ALIAS("platform:ds2780-battery");