These changes are the raw update to linux-4.4.6-rt14. Kernel sources

are taken from kernel.org, and rt patch from the rt wiki download page.

During the rebasing, the following patch collided:

Force tick interrupt and get rid of softirq magic(I70131fb85).

Collisions have been removed because its logic was found on the
source already.

Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>

1 files changed, 1375 insertions, 0 deletions

diff --git a/kernel/drivers/power/bq27xxx_battery.c b/kernel/drivers/power/bq27xxx_battery.c
new file mode 100644
index 000000000..880233ce9
--- /dev/null
+++ b/kernel/drivers/power/bq27xxx_battery.c
@@ -0,0 +1,1375 @@
+/*
+ * BQ27xxx battery driver
+ *
+ * Copyright (C) 2008 Rodolfo Giometti <giometti@linux.it>
+ * Copyright (C) 2008 Eurotech S.p.A. <info@eurotech.it>
+ * Copyright (C) 2010-2011 Lars-Peter Clausen <lars@metafoo.de>
+ * Copyright (C) 2011 Pali Rohár <pali.rohar@gmail.com>
+ *
+ * Based on a previous work by Copyright (C) 2008 Texas Instruments, Inc.
+ *
+ * This package 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.
+ *
+ * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Datasheets:
+ * http://www.ti.com/product/bq27000
+ * http://www.ti.com/product/bq27200
+ * http://www.ti.com/product/bq27010
+ * http://www.ti.com/product/bq27210
+ * http://www.ti.com/product/bq27500
+ * http://www.ti.com/product/bq27510-g3
+ * http://www.ti.com/product/bq27520-g4
+ * http://www.ti.com/product/bq27530-g1
+ * http://www.ti.com/product/bq27531-g1
+ * http://www.ti.com/product/bq27541-g1
+ * http://www.ti.com/product/bq27542-g1
+ * http://www.ti.com/product/bq27546-g1
+ * http://www.ti.com/product/bq27742-g1
+ * http://www.ti.com/product/bq27545-g1
+ * http://www.ti.com/product/bq27421-g1
+ * http://www.ti.com/product/bq27425-g1
+ * http://www.ti.com/product/bq27411-g1
+ * http://www.ti.com/product/bq27621-g1
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/param.h>
+#include <linux/jiffies.h>
+#include <linux/workqueue.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/idr.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <asm/unaligned.h>
+
+#include <linux/power/bq27xxx_battery.h>
+
+#define DRIVER_VERSION		"1.2.0"
+
+#define BQ27XXX_MANUFACTURER	"Texas Instruments"
+
+/* BQ27XXX Flags */
+#define BQ27XXX_FLAG_DSC	BIT(0)
+#define BQ27XXX_FLAG_SOCF	BIT(1) /* State-of-Charge threshold final */
+#define BQ27XXX_FLAG_SOC1	BIT(2) /* State-of-Charge threshold 1 */
+#define BQ27XXX_FLAG_FC		BIT(9)
+#define BQ27XXX_FLAG_OTD	BIT(14)
+#define BQ27XXX_FLAG_OTC	BIT(15)
+#define BQ27XXX_FLAG_UT		BIT(14)
+#define BQ27XXX_FLAG_OT		BIT(15)
+
+/* BQ27000 has different layout for Flags register */
+#define BQ27000_FLAG_EDVF	BIT(0) /* Final End-of-Discharge-Voltage flag */
+#define BQ27000_FLAG_EDV1	BIT(1) /* First End-of-Discharge-Voltage flag */
+#define BQ27000_FLAG_CI		BIT(4) /* Capacity Inaccurate flag */
+#define BQ27000_FLAG_FC		BIT(5)
+#define BQ27000_FLAG_CHGS	BIT(7) /* Charge state flag */
+
+#define BQ27XXX_RS			(20) /* Resistor sense mOhm */
+#define BQ27XXX_POWER_CONSTANT		(29200) /* 29.2 µV^2 * 1000 */
+#define BQ27XXX_CURRENT_CONSTANT	(3570) /* 3.57 µV * 1000 */
+
+struct bq27xxx_device_info;
+struct bq27xxx_access_methods {
+	int (*read)(struct bq27xxx_device_info *di, u8 reg, bool single);
+};
+
+#define INVALID_REG_ADDR	0xff
+
+/*
+ * bq27xxx_reg_index - Register names
+ *
+ * These are indexes into a device's register mapping array.
+ */
+enum bq27xxx_reg_index {
+	BQ27XXX_REG_CTRL = 0,	/* Control */
+	BQ27XXX_REG_TEMP,	/* Temperature */
+	BQ27XXX_REG_INT_TEMP,	/* Internal Temperature */
+	BQ27XXX_REG_VOLT,	/* Voltage */
+	BQ27XXX_REG_AI,		/* Average Current */
+	BQ27XXX_REG_FLAGS,	/* Flags */
+	BQ27XXX_REG_TTE,	/* Time-to-Empty */
+	BQ27XXX_REG_TTF,	/* Time-to-Full */
+	BQ27XXX_REG_TTES,	/* Time-to-Empty Standby */
+	BQ27XXX_REG_TTECP,	/* Time-to-Empty at Constant Power */
+	BQ27XXX_REG_NAC,	/* Nominal Available Capacity */
+	BQ27XXX_REG_FCC,	/* Full Charge Capacity */
+	BQ27XXX_REG_CYCT,	/* Cycle Count */
+	BQ27XXX_REG_AE,		/* Available Energy */
+	BQ27XXX_REG_SOC,	/* State-of-Charge */
+	BQ27XXX_REG_DCAP,	/* Design Capacity */
+	BQ27XXX_REG_AP,		/* Average Power */
+};
+
+struct bq27xxx_reg_cache {
+	int temperature;
+	int time_to_empty;
+	int time_to_empty_avg;
+	int time_to_full;
+	int charge_full;
+	int cycle_count;
+	int capacity;
+	int energy;
+	int flags;
+	int power_avg;
+	int health;
+};
+
+struct bq27xxx_device_info {
+	struct device		*dev;
+	int			id;
+	enum bq27xxx_chip	chip;
+
+	struct bq27xxx_reg_cache cache;
+	int charge_design_full;
+
+	unsigned long last_update;
+	struct delayed_work work;
+
+	struct power_supply	*bat;
+
+	struct bq27xxx_access_methods bus;
+
+	struct mutex lock;
+
+	u8 *regs;
+};
+
+/* Register mappings */
+static u8 bq27000_regs[] = {
+	0x00,	/* CONTROL	*/
+	0x06,	/* TEMP		*/
+	INVALID_REG_ADDR,	/* INT TEMP - NA*/
+	0x08,	/* VOLT		*/
+	0x14,	/* AVG CURR	*/
+	0x0a,	/* FLAGS	*/
+	0x16,	/* TTE		*/
+	0x18,	/* TTF		*/
+	0x1c,	/* TTES		*/
+	0x26,	/* TTECP	*/
+	0x0c,	/* NAC		*/
+	0x12,	/* LMD(FCC)	*/
+	0x2a,	/* CYCT		*/
+	0x22,	/* AE		*/
+	0x0b,	/* SOC(RSOC)	*/
+	0x76,	/* DCAP(ILMD)	*/
+	0x24,	/* AP		*/
+};
+
+static u8 bq27010_regs[] = {
+	0x00,	/* CONTROL	*/
+	0x06,	/* TEMP		*/
+	INVALID_REG_ADDR,	/* INT TEMP - NA*/
+	0x08,	/* VOLT		*/
+	0x14,	/* AVG CURR	*/
+	0x0a,	/* FLAGS	*/
+	0x16,	/* TTE		*/
+	0x18,	/* TTF		*/
+	0x1c,	/* TTES		*/
+	0x26,	/* TTECP	*/
+	0x0c,	/* NAC		*/
+	0x12,	/* LMD(FCC)	*/
+	0x2a,	/* CYCT		*/
+	INVALID_REG_ADDR,	/* AE - NA	*/
+	0x0b,	/* SOC(RSOC)	*/
+	0x76,	/* DCAP(ILMD)	*/
+	INVALID_REG_ADDR,	/* AP - NA	*/
+};
+
+static u8 bq27500_regs[] = {
+	0x00,	/* CONTROL	*/
+	0x06,	/* TEMP		*/
+	0x28,	/* INT TEMP	*/
+	0x08,	/* VOLT		*/
+	0x14,	/* AVG CURR	*/
+	0x0a,	/* FLAGS	*/
+	0x16,	/* TTE		*/
+	INVALID_REG_ADDR,	/* TTF - NA	*/
+	0x1a,	/* TTES		*/
+	INVALID_REG_ADDR,	/* TTECP - NA	*/
+	0x0c,	/* NAC		*/
+	0x12,	/* LMD(FCC)	*/
+	0x1e,	/* CYCT		*/
+	INVALID_REG_ADDR,	/* AE - NA	*/
+	0x20,	/* SOC(RSOC)	*/
+	0x2e,	/* DCAP(ILMD)	*/
+	INVALID_REG_ADDR,	/* AP - NA	*/
+};
+
+static u8 bq27530_regs[] = {
+	0x00,	/* CONTROL	*/
+	0x06,	/* TEMP		*/
+	0x32,	/* INT TEMP	*/
+	0x08,	/* VOLT		*/
+	0x14,	/* AVG CURR	*/
+	0x0a,	/* FLAGS	*/
+	0x16,	/* TTE		*/
+	INVALID_REG_ADDR,	/* TTF - NA	*/
+	INVALID_REG_ADDR,	/* TTES - NA	*/
+	INVALID_REG_ADDR,	/* TTECP - NA	*/
+	0x0c,	/* NAC		*/
+	0x12,	/* LMD(FCC)	*/
+	0x2a,	/* CYCT		*/
+	INVALID_REG_ADDR,	/* AE - NA	*/
+	0x2c,	/* SOC(RSOC)	*/
+	INVALID_REG_ADDR,	/* DCAP - NA	*/
+	0x24,	/* AP		*/
+};
+
+static u8 bq27541_regs[] = {
+	0x00,	/* CONTROL	*/
+	0x06,	/* TEMP		*/
+	0x28,	/* INT TEMP	*/
+	0x08,	/* VOLT		*/
+	0x14,	/* AVG CURR	*/
+	0x0a,	/* FLAGS	*/
+	0x16,	/* TTE		*/
+	INVALID_REG_ADDR,	/* TTF - NA	*/
+	INVALID_REG_ADDR,	/* TTES - NA	*/
+	INVALID_REG_ADDR,	/* TTECP - NA	*/
+	0x0c,	/* NAC		*/
+	0x12,	/* LMD(FCC)	*/
+	0x2a,	/* CYCT		*/
+	INVALID_REG_ADDR,	/* AE - NA	*/
+	0x2c,	/* SOC(RSOC)	*/
+	0x3c,	/* DCAP		*/
+	0x76,	/* AP		*/
+};
+
+static u8 bq27545_regs[] = {
+	0x00,	/* CONTROL	*/
+	0x06,	/* TEMP		*/
+	0x28,	/* INT TEMP	*/
+	0x08,	/* VOLT		*/
+	0x14,	/* AVG CURR	*/
+	0x0a,	/* FLAGS	*/
+	0x16,	/* TTE		*/
+	INVALID_REG_ADDR,	/* TTF - NA	*/
+	INVALID_REG_ADDR,	/* TTES - NA	*/
+	INVALID_REG_ADDR,	/* TTECP - NA	*/
+	0x0c,	/* NAC		*/
+	0x12,	/* LMD(FCC)	*/
+	0x2a,	/* CYCT		*/
+	INVALID_REG_ADDR,	/* AE - NA	*/
+	0x2c,	/* SOC(RSOC)	*/
+	INVALID_REG_ADDR,	/* DCAP - NA */
+	0x24,	/* AP		*/
+};
+
+static u8 bq27421_regs[] = {
+	0x00,	/* CONTROL	*/
+	0x02,	/* TEMP		*/
+	0x1e,	/* INT TEMP	*/
+	0x04,	/* VOLT		*/
+	0x10,	/* AVG CURR	*/
+	0x06,	/* FLAGS	*/
+	INVALID_REG_ADDR,	/* TTE - NA	*/
+	INVALID_REG_ADDR,	/* TTF - NA	*/
+	INVALID_REG_ADDR,	/* TTES - NA	*/
+	INVALID_REG_ADDR,	/* TTECP - NA	*/
+	0x08,	/* NAC		*/
+	0x0e,	/* FCC		*/
+	INVALID_REG_ADDR,	/* CYCT - NA	*/
+	INVALID_REG_ADDR,	/* AE - NA	*/
+	0x1c,	/* SOC		*/
+	0x3c,	/* DCAP		*/
+	0x18,	/* AP		*/
+};
+
+static u8 *bq27xxx_regs[] = {
+	[BQ27000] = bq27000_regs,
+	[BQ27010] = bq27010_regs,
+	[BQ27500] = bq27500_regs,
+	[BQ27530] = bq27530_regs,
+	[BQ27541] = bq27541_regs,
+	[BQ27545] = bq27545_regs,
+	[BQ27421] = bq27421_regs,
+};
+
+static enum power_supply_property bq27000_battery_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+	POWER_SUPPLY_PROP_TEMP,
+	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
+	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
+	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+	POWER_SUPPLY_PROP_CYCLE_COUNT,
+	POWER_SUPPLY_PROP_ENERGY_NOW,
+	POWER_SUPPLY_PROP_POWER_AVG,
+	POWER_SUPPLY_PROP_HEALTH,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+static enum power_supply_property bq27010_battery_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+	POWER_SUPPLY_PROP_TEMP,
+	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
+	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
+	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+	POWER_SUPPLY_PROP_CYCLE_COUNT,
+	POWER_SUPPLY_PROP_HEALTH,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+static enum power_supply_property bq27500_battery_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+	POWER_SUPPLY_PROP_TEMP,
+	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+	POWER_SUPPLY_PROP_CYCLE_COUNT,
+	POWER_SUPPLY_PROP_HEALTH,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+static enum power_supply_property bq27530_battery_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+	POWER_SUPPLY_PROP_TEMP,
+	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+	POWER_SUPPLY_PROP_POWER_AVG,
+	POWER_SUPPLY_PROP_HEALTH,
+	POWER_SUPPLY_PROP_CYCLE_COUNT,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+static enum power_supply_property bq27541_battery_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+	POWER_SUPPLY_PROP_TEMP,
+	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+	POWER_SUPPLY_PROP_CYCLE_COUNT,
+	POWER_SUPPLY_PROP_POWER_AVG,
+	POWER_SUPPLY_PROP_HEALTH,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+static enum power_supply_property bq27545_battery_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+	POWER_SUPPLY_PROP_TEMP,
+	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+	POWER_SUPPLY_PROP_HEALTH,
+	POWER_SUPPLY_PROP_CYCLE_COUNT,
+	POWER_SUPPLY_PROP_POWER_AVG,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+static enum power_supply_property bq27421_battery_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+	POWER_SUPPLY_PROP_TEMP,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+#define BQ27XXX_PROP(_id, _prop)		\
+	[_id] = {				\
+		.props = _prop,			\
+		.size = ARRAY_SIZE(_prop),	\
+	}
+
+static struct {
+	enum power_supply_property *props;
+	size_t size;
+} bq27xxx_battery_props[] = {
+	BQ27XXX_PROP(BQ27000, bq27000_battery_props),
+	BQ27XXX_PROP(BQ27010, bq27010_battery_props),
+	BQ27XXX_PROP(BQ27500, bq27500_battery_props),
+	BQ27XXX_PROP(BQ27530, bq27530_battery_props),
+	BQ27XXX_PROP(BQ27541, bq27541_battery_props),
+	BQ27XXX_PROP(BQ27545, bq27545_battery_props),
+	BQ27XXX_PROP(BQ27421, bq27421_battery_props),
+};
+
+static unsigned int poll_interval = 360;
+module_param(poll_interval, uint, 0644);
+MODULE_PARM_DESC(poll_interval,
+		 "battery poll interval in seconds - 0 disables polling");
+
+/*
+ * Common code for BQ27xxx devices
+ */
+
+static inline int bq27xxx_read(struct bq27xxx_device_info *di, int reg_index,
+			       bool single)
+{
+	/* Reports EINVAL for invalid/missing registers */
+	if (!di || di->regs[reg_index] == INVALID_REG_ADDR)
+		return -EINVAL;
+
+	return di->bus.read(di, di->regs[reg_index], single);
+}
+
+/*
+ * Return the battery State-of-Charge
+ * Or < 0 if something fails.
+ */
+static int bq27xxx_battery_read_soc(struct bq27xxx_device_info *di)
+{
+	int soc;
+
+	soc = bq27xxx_read(di, BQ27XXX_REG_SOC, false);
+
+	if (soc < 0)
+		dev_dbg(di->dev, "error reading State-of-Charge\n");
+
+	return soc;
+}
+
+/*
+ * Return a battery charge value in µAh
+ * Or < 0 if something fails.
+ */
+static int bq27xxx_battery_read_charge(struct bq27xxx_device_info *di, u8 reg)
+{
+	int charge;
+
+	charge = bq27xxx_read(di, reg, false);
+	if (charge < 0) {
+		dev_dbg(di->dev, "error reading charge register %02x: %d\n",
+			reg, charge);
+		return charge;
+	}
+
+	if (di->chip == BQ27000 || di->chip == BQ27010)
+		charge *= BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
+	else
+		charge *= 1000;
+
+	return charge;
+}
+
+/*
+ * Return the battery Nominal available capacity in µAh
+ * Or < 0 if something fails.
+ */
+static inline int bq27xxx_battery_read_nac(struct bq27xxx_device_info *di)
+{
+	int flags;
+
+	if (di->chip == BQ27000 || di->chip == BQ27010) {
+		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, true);
+		if (flags >= 0 && (flags & BQ27000_FLAG_CI))
+			return -ENODATA;
+	}
+
+	return bq27xxx_battery_read_charge(di, BQ27XXX_REG_NAC);
+}
+
+/*
+ * Return the battery Full Charge Capacity in µAh
+ * Or < 0 if something fails.
+ */
+static inline int bq27xxx_battery_read_fcc(struct bq27xxx_device_info *di)
+{
+	return bq27xxx_battery_read_charge(di, BQ27XXX_REG_FCC);
+}
+
+/*
+ * Return the Design Capacity in µAh
+ * Or < 0 if something fails.
+ */
+static int bq27xxx_battery_read_dcap(struct bq27xxx_device_info *di)
+{
+	int dcap;
+
+	dcap = bq27xxx_read(di, BQ27XXX_REG_DCAP, false);
+
+	if (dcap < 0) {
+		dev_dbg(di->dev, "error reading initial last measured discharge\n");
+		return dcap;
+	}
+
+	if (di->chip == BQ27000 || di->chip == BQ27010)
+		dcap *= BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
+	else
+		dcap *= 1000;
+
+	return dcap;
+}
+
+/*
+ * Return the battery Available energy in µWh
+ * Or < 0 if something fails.
+ */
+static int bq27xxx_battery_read_energy(struct bq27xxx_device_info *di)
+{
+	int ae;
+
+	ae = bq27xxx_read(di, BQ27XXX_REG_AE, false);
+	if (ae < 0) {
+		dev_dbg(di->dev, "error reading available energy\n");
+		return ae;
+	}
+
+	if (di->chip == BQ27000 || di->chip == BQ27010)
+		ae *= BQ27XXX_POWER_CONSTANT / BQ27XXX_RS;
+	else
+		ae *= 1000;
+
+	return ae;
+}
+
+/*
+ * Return the battery temperature in tenths of degree Kelvin
+ * Or < 0 if something fails.
+ */
+static int bq27xxx_battery_read_temperature(struct bq27xxx_device_info *di)
+{
+	int temp;
+
+	temp = bq27xxx_read(di, BQ27XXX_REG_TEMP, false);
+	if (temp < 0) {
+		dev_err(di->dev, "error reading temperature\n");
+		return temp;
+	}
+
+	if (di->chip == BQ27000 || di->chip == BQ27010)
+		temp = 5 * temp / 2;
+
+	return temp;
+}
+
+/*
+ * Return the battery Cycle count total
+ * Or < 0 if something fails.
+ */
+static int bq27xxx_battery_read_cyct(struct bq27xxx_device_info *di)
+{
+	int cyct;
+
+	cyct = bq27xxx_read(di, BQ27XXX_REG_CYCT, false);
+	if (cyct < 0)
+		dev_err(di->dev, "error reading cycle count total\n");
+
+	return cyct;
+}
+
+/*
+ * Read a time register.
+ * Return < 0 if something fails.
+ */
+static int bq27xxx_battery_read_time(struct bq27xxx_device_info *di, u8 reg)
+{
+	int tval;
+
+	tval = bq27xxx_read(di, reg, false);
+	if (tval < 0) {
+		dev_dbg(di->dev, "error reading time register %02x: %d\n",
+			reg, tval);
+		return tval;
+	}
+
+	if (tval == 65535)
+		return -ENODATA;
+
+	return tval * 60;
+}
+
+/*
+ * Read an average power register.
+ * Return < 0 if something fails.
+ */
+static int bq27xxx_battery_read_pwr_avg(struct bq27xxx_device_info *di)
+{
+	int tval;
+
+	tval = bq27xxx_read(di, BQ27XXX_REG_AP, false);
+	if (tval < 0) {
+		dev_err(di->dev, "error reading average power register  %02x: %d\n",
+			BQ27XXX_REG_AP, tval);
+		return tval;
+	}
+
+	if (di->chip == BQ27000 || di->chip == BQ27010)
+		return (tval * BQ27XXX_POWER_CONSTANT) / BQ27XXX_RS;
+	else
+		return tval;
+}
+
+/*
+ * Returns true if a battery over temperature condition is detected
+ */
+static bool bq27xxx_battery_overtemp(struct bq27xxx_device_info *di, u16 flags)
+{
+	if (di->chip == BQ27500 || di->chip == BQ27541 || di->chip == BQ27545)
+		return flags & (BQ27XXX_FLAG_OTC | BQ27XXX_FLAG_OTD);
+	if (di->chip == BQ27530 || di->chip == BQ27421)
+		return flags & BQ27XXX_FLAG_OT;
+
+	return false;
+}
+
+/*
+ * Returns true if a battery under temperature condition is detected
+ */
+static bool bq27xxx_battery_undertemp(struct bq27xxx_device_info *di, u16 flags)
+{
+	if (di->chip == BQ27530 || di->chip == BQ27421)
+		return flags & BQ27XXX_FLAG_UT;
+
+	return false;
+}
+
+/*
+ * Returns true if a low state of charge condition is detected
+ */
+static bool bq27xxx_battery_dead(struct bq27xxx_device_info *di, u16 flags)
+{
+	if (di->chip == BQ27000 || di->chip == BQ27010)
+		return flags & (BQ27000_FLAG_EDV1 | BQ27000_FLAG_EDVF);
+	else
+		return flags & (BQ27XXX_FLAG_SOC1 | BQ27XXX_FLAG_SOCF);
+}
+
+/*
+ * Read flag register.
+ * Return < 0 if something fails.
+ */
+static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
+{
+	int flags;
+
+	flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
+	if (flags < 0) {
+		dev_err(di->dev, "error reading flag register:%d\n", flags);
+		return flags;
+	}
+
+	/* Unlikely but important to return first */
+	if (unlikely(bq27xxx_battery_overtemp(di, flags)))
+		return POWER_SUPPLY_HEALTH_OVERHEAT;
+	if (unlikely(bq27xxx_battery_undertemp(di, flags)))
+		return POWER_SUPPLY_HEALTH_COLD;
+	if (unlikely(bq27xxx_battery_dead(di, flags)))
+		return POWER_SUPPLY_HEALTH_DEAD;
+
+	return POWER_SUPPLY_HEALTH_GOOD;
+}
+
+static void bq27xxx_battery_update(struct bq27xxx_device_info *di)
+{
+	struct bq27xxx_reg_cache cache = {0, };
+	bool has_ci_flag = di->chip == BQ27000 || di->chip == BQ27010;
+	bool has_singe_flag = di->chip == BQ27000 || di->chip == BQ27010;
+
+	cache.flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
+	if ((cache.flags & 0xff) == 0xff)
+		cache.flags = -1; /* read error */
+	if (cache.flags >= 0) {
+		cache.temperature = bq27xxx_battery_read_temperature(di);
+		if (has_ci_flag && (cache.flags & BQ27000_FLAG_CI)) {
+			dev_info(di->dev, "battery is not calibrated! ignoring capacity values\n");
+			cache.capacity = -ENODATA;
+			cache.energy = -ENODATA;
+			cache.time_to_empty = -ENODATA;
+			cache.time_to_empty_avg = -ENODATA;
+			cache.time_to_full = -ENODATA;
+			cache.charge_full = -ENODATA;
+			cache.health = -ENODATA;
+		} else {
+			if (di->regs[BQ27XXX_REG_TTE] != INVALID_REG_ADDR)
+				cache.time_to_empty = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTE);
+			if (di->regs[BQ27XXX_REG_TTECP] != INVALID_REG_ADDR)
+				cache.time_to_empty_avg = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTECP);
+			if (di->regs[BQ27XXX_REG_TTF] != INVALID_REG_ADDR)
+				cache.time_to_full = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTF);
+			cache.charge_full = bq27xxx_battery_read_fcc(di);
+			cache.capacity = bq27xxx_battery_read_soc(di);
+			if (di->regs[BQ27XXX_REG_AE] != INVALID_REG_ADDR)
+				cache.energy = bq27xxx_battery_read_energy(di);
+			cache.health = bq27xxx_battery_read_health(di);
+		}
+		if (di->regs[BQ27XXX_REG_CYCT] != INVALID_REG_ADDR)
+			cache.cycle_count = bq27xxx_battery_read_cyct(di);
+		if (di->regs[BQ27XXX_REG_AP] != INVALID_REG_ADDR)
+			cache.power_avg = bq27xxx_battery_read_pwr_avg(di);
+
+		/* We only have to read charge design full once */
+		if (di->charge_design_full <= 0)
+			di->charge_design_full = bq27xxx_battery_read_dcap(di);
+	}
+
+	if (di->cache.capacity != cache.capacity)
+		power_supply_changed(di->bat);
+
+	if (memcmp(&di->cache, &cache, sizeof(cache)) != 0)
+		di->cache = cache;
+
+	di->last_update = jiffies;
+}
+
+static void bq27xxx_battery_poll(struct work_struct *work)
+{
+	struct bq27xxx_device_info *di =
+			container_of(work, struct bq27xxx_device_info,
+				     work.work);
+
+	bq27xxx_battery_update(di);
+
+	if (poll_interval > 0) {
+		/* The timer does not have to be accurate. */
+		set_timer_slack(&di->work.timer, poll_interval * HZ / 4);
+		schedule_delayed_work(&di->work, poll_interval * HZ);
+	}
+}
+
+/*
+ * Return the battery average current in µA
+ * Note that current can be negative signed as well
+ * Or 0 if something fails.
+ */
+static int bq27xxx_battery_current(struct bq27xxx_device_info *di,
+				   union power_supply_propval *val)
+{
+	int curr;
+	int flags;
+
+	curr = bq27xxx_read(di, BQ27XXX_REG_AI, false);
+	if (curr < 0) {
+		dev_err(di->dev, "error reading current\n");
+		return curr;
+	}
+
+	if (di->chip == BQ27000 || di->chip == BQ27010) {
+		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
+		if (flags & BQ27000_FLAG_CHGS) {
+			dev_dbg(di->dev, "negative current!\n");
+			curr = -curr;
+		}
+
+		val->intval = curr * BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
+	} else {
+		/* Other gauges return signed value */
+		val->intval = (int)((s16)curr) * 1000;
+	}
+
+	return 0;
+}
+
+static int bq27xxx_battery_status(struct bq27xxx_device_info *di,
+				  union power_supply_propval *val)
+{
+	int status;
+
+	if (di->chip == BQ27000 || di->chip == BQ27010) {
+		if (di->cache.flags & BQ27000_FLAG_FC)
+			status = POWER_SUPPLY_STATUS_FULL;
+		else if (di->cache.flags & BQ27000_FLAG_CHGS)
+			status = POWER_SUPPLY_STATUS_CHARGING;
+		else if (power_supply_am_i_supplied(di->bat))
+			status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+		else
+			status = POWER_SUPPLY_STATUS_DISCHARGING;
+	} else {
+		if (di->cache.flags & BQ27XXX_FLAG_FC)
+			status = POWER_SUPPLY_STATUS_FULL;
+		else if (di->cache.flags & BQ27XXX_FLAG_DSC)
+			status = POWER_SUPPLY_STATUS_DISCHARGING;
+		else
+			status = POWER_SUPPLY_STATUS_CHARGING;
+	}
+
+	val->intval = status;
+
+	return 0;
+}
+
+static int bq27xxx_battery_capacity_level(struct bq27xxx_device_info *di,
+					  union power_supply_propval *val)
+{
+	int level;
+
+	if (di->chip == BQ27000 || di->chip == BQ27010) {
+		if (di->cache.flags & BQ27000_FLAG_FC)
+			level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
+		else if (di->cache.flags & BQ27000_FLAG_EDV1)
+			level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
+		else if (di->cache.flags & BQ27000_FLAG_EDVF)
+			level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
+		else
+			level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
+	} else {
+		if (di->cache.flags & BQ27XXX_FLAG_FC)
+			level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
+		else if (di->cache.flags & BQ27XXX_FLAG_SOC1)
+			level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
+		else if (di->cache.flags & BQ27XXX_FLAG_SOCF)
+			level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
+		else
+			level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
+	}
+
+	val->intval = level;
+
+	return 0;
+}
+
+/*
+ * Return the battery Voltage in millivolts
+ * Or < 0 if something fails.
+ */
+static int bq27xxx_battery_voltage(struct bq27xxx_device_info *di,
+				   union power_supply_propval *val)
+{
+	int volt;
+
+	volt = bq27xxx_read(di, BQ27XXX_REG_VOLT, false);
+	if (volt < 0) {
+		dev_err(di->dev, "error reading voltage\n");
+		return volt;
+	}
+
+	val->intval = volt * 1000;
+
+	return 0;
+}
+
+static int bq27xxx_simple_value(int value,
+				union power_supply_propval *val)
+{
+	if (value < 0)
+		return value;
+
+	val->intval = value;
+
+	return 0;
+}
+
+static int bq27xxx_battery_get_property(struct power_supply *psy,
+					enum power_supply_property psp,
+					union power_supply_propval *val)
+{
+	int ret = 0;
+	struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
+
+	mutex_lock(&di->lock);
+	if (time_is_before_jiffies(di->last_update + 5 * HZ)) {
+		cancel_delayed_work_sync(&di->work);
+		bq27xxx_battery_poll(&di->work.work);
+	}
+	mutex_unlock(&di->lock);
+
+	if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
+		return -ENODEV;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_STATUS:
+		ret = bq27xxx_battery_status(di, val);
+		break;
+	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+		ret = bq27xxx_battery_voltage(di, val);
+		break;
+	case POWER_SUPPLY_PROP_PRESENT:
+		val->intval = di->cache.flags < 0 ? 0 : 1;
+		break;
+	case POWER_SUPPLY_PROP_CURRENT_NOW:
+		ret = bq27xxx_battery_current(di, val);
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY:
+		ret = bq27xxx_simple_value(di->cache.capacity, val);
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
+		ret = bq27xxx_battery_capacity_level(di, val);
+		break;
+	case POWER_SUPPLY_PROP_TEMP:
+		ret = bq27xxx_simple_value(di->cache.temperature, val);
+		if (ret == 0)
+			val->intval -= 2731; /* convert decidegree k to c */
+		break;
+	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
+		ret = bq27xxx_simple_value(di->cache.time_to_empty, val);
+		break;
+	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
+		ret = bq27xxx_simple_value(di->cache.time_to_empty_avg, val);
+		break;
+	case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
+		ret = bq27xxx_simple_value(di->cache.time_to_full, val);
+		break;
+	case POWER_SUPPLY_PROP_TECHNOLOGY:
+		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_NOW:
+		ret = bq27xxx_simple_value(bq27xxx_battery_read_nac(di), val);
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_FULL:
+		ret = bq27xxx_simple_value(di->cache.charge_full, val);
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
+		ret = bq27xxx_simple_value(di->charge_design_full, val);
+		break;
+	case POWER_SUPPLY_PROP_CYCLE_COUNT:
+		ret = bq27xxx_simple_value(di->cache.cycle_count, val);
+		break;
+	case POWER_SUPPLY_PROP_ENERGY_NOW:
+		ret = bq27xxx_simple_value(di->cache.energy, val);
+		break;
+	case POWER_SUPPLY_PROP_POWER_AVG:
+		ret = bq27xxx_simple_value(di->cache.power_avg, val);
+		break;
+	case POWER_SUPPLY_PROP_HEALTH:
+		ret = bq27xxx_simple_value(di->cache.health, val);
+		break;
+	case POWER_SUPPLY_PROP_MANUFACTURER:
+		val->strval = BQ27XXX_MANUFACTURER;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return ret;
+}
+
+static void bq27xxx_external_power_changed(struct power_supply *psy)
+{
+	struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
+
+	cancel_delayed_work_sync(&di->work);
+	schedule_delayed_work(&di->work, 0);
+}
+
+static int bq27xxx_powersupply_init(struct bq27xxx_device_info *di,
+				    const char *name)
+{
+	int ret;
+	struct power_supply_desc *psy_desc;
+	struct power_supply_config psy_cfg = { .drv_data = di, };
+
+	psy_desc = devm_kzalloc(di->dev, sizeof(*psy_desc), GFP_KERNEL);
+	if (!psy_desc)
+		return -ENOMEM;
+
+	psy_desc->name = name;
+	psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
+	psy_desc->properties = bq27xxx_battery_props[di->chip].props;
+	psy_desc->num_properties = bq27xxx_battery_props[di->chip].size;
+	psy_desc->get_property = bq27xxx_battery_get_property;
+	psy_desc->external_power_changed = bq27xxx_external_power_changed;
+
+	INIT_DELAYED_WORK(&di->work, bq27xxx_battery_poll);
+	mutex_init(&di->lock);
+
+	di->bat = power_supply_register_no_ws(di->dev, psy_desc, &psy_cfg);
+	if (IS_ERR(di->bat)) {
+		ret = PTR_ERR(di->bat);
+		dev_err(di->dev, "failed to register battery: %d\n", ret);
+		return ret;
+	}
+
+	dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
+
+	bq27xxx_battery_update(di);
+
+	return 0;
+}
+
+static void bq27xxx_powersupply_unregister(struct bq27xxx_device_info *di)
+{
+	/*
+	 * power_supply_unregister call bq27xxx_battery_get_property which
+	 * call bq27xxx_battery_poll.
+	 * Make sure that bq27xxx_battery_poll will not call
+	 * schedule_delayed_work again after unregister (which cause OOPS).
+	 */
+	poll_interval = 0;
+
+	cancel_delayed_work_sync(&di->work);
+
+	power_supply_unregister(di->bat);
+
+	mutex_destroy(&di->lock);
+}
+
+/* i2c specific code */
+#ifdef CONFIG_BATTERY_BQ27XXX_I2C
+
+/* If the system has several batteries we need a different name for each
+ * of them...
+ */
+static DEFINE_IDR(battery_id);
+static DEFINE_MUTEX(battery_mutex);
+
+static irqreturn_t bq27xxx_battery_irq_handler_thread(int irq, void *data)
+{
+	struct bq27xxx_device_info *di = data;
+
+	bq27xxx_battery_update(di);
+
+	return IRQ_HANDLED;
+}
+
+static int bq27xxx_battery_i2c_read(struct bq27xxx_device_info *di, u8 reg,
+				    bool single)
+{
+	struct i2c_client *client = to_i2c_client(di->dev);
+	struct i2c_msg msg[2];
+	unsigned char data[2];
+	int ret;
+
+	if (!client->adapter)
+		return -ENODEV;
+
+	msg[0].addr = client->addr;
+	msg[0].flags = 0;
+	msg[0].buf = &reg;
+	msg[0].len = sizeof(reg);
+	msg[1].addr = client->addr;
+	msg[1].flags = I2C_M_RD;
+	msg[1].buf = data;
+	if (single)
+		msg[1].len = 1;
+	else
+		msg[1].len = 2;
+
+	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
+	if (ret < 0)
+		return ret;
+
+	if (!single)
+		ret = get_unaligned_le16(data);
+	else
+		ret = data[0];
+
+	return ret;
+}
+
+static int bq27xxx_battery_i2c_probe(struct i2c_client *client,
+				     const struct i2c_device_id *id)
+{
+	char *name;
+	struct bq27xxx_device_info *di;
+	int num;
+	int retval = 0;
+
+	/* Get new ID for the new battery device */
+	mutex_lock(&battery_mutex);
+	num = idr_alloc(&battery_id, client, 0, 0, GFP_KERNEL);
+	mutex_unlock(&battery_mutex);
+	if (num < 0)
+		return num;
+
+	name = devm_kasprintf(&client->dev, GFP_KERNEL, "%s-%d", id->name, num);
+	if (!name) {
+		retval = -ENOMEM;
+		goto batt_failed;
+	}
+
+	di = devm_kzalloc(&client->dev, sizeof(*di), GFP_KERNEL);
+	if (!di) {
+		retval = -ENOMEM;
+		goto batt_failed;
+	}
+
+	di->id = num;
+	di->dev = &client->dev;
+	di->chip = id->driver_data;
+	di->bus.read = &bq27xxx_battery_i2c_read;
+	di->regs = bq27xxx_regs[di->chip];
+
+	retval = bq27xxx_powersupply_init(di, name);
+	if (retval)
+		goto batt_failed;
+
+	/* Schedule a polling after about 1 min */
+	schedule_delayed_work(&di->work, 60 * HZ);
+
+	i2c_set_clientdata(client, di);
+
+	if (client->irq) {
+		retval = devm_request_threaded_irq(&client->dev, client->irq,
+				NULL, bq27xxx_battery_irq_handler_thread,
+				IRQF_ONESHOT,
+				name, di);
+		if (retval) {
+			dev_err(&client->dev,
+				"Unable to register IRQ %d error %d\n",
+				client->irq, retval);
+			return retval;
+		}
+	}
+
+	return 0;
+
+batt_failed:
+	mutex_lock(&battery_mutex);
+	idr_remove(&battery_id, num);
+	mutex_unlock(&battery_mutex);
+
+	return retval;
+}
+
+static int bq27xxx_battery_i2c_remove(struct i2c_client *client)
+{
+	struct bq27xxx_device_info *di = i2c_get_clientdata(client);
+
+	bq27xxx_powersupply_unregister(di);
+
+	mutex_lock(&battery_mutex);
+	idr_remove(&battery_id, di->id);
+	mutex_unlock(&battery_mutex);
+
+	return 0;
+}
+
+static const struct i2c_device_id bq27xxx_id[] = {
+	{ "bq27200", BQ27000 },
+	{ "bq27210", BQ27010 },
+	{ "bq27500", BQ27500 },
+	{ "bq27510", BQ27500 },
+	{ "bq27520", BQ27500 },
+	{ "bq27530", BQ27530 },
+	{ "bq27531", BQ27530 },
+	{ "bq27541", BQ27541 },
+	{ "bq27542", BQ27541 },
+	{ "bq27546", BQ27541 },
+	{ "bq27742", BQ27541 },
+	{ "bq27545", BQ27545 },
+	{ "bq27421", BQ27421 },
+	{ "bq27425", BQ27421 },
+	{ "bq27441", BQ27421 },
+	{ "bq27621", BQ27421 },
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, bq27xxx_id);
+
+static struct i2c_driver bq27xxx_battery_i2c_driver = {
+	.driver = {
+		.name = "bq27xxx-battery",
+	},
+	.probe = bq27xxx_battery_i2c_probe,
+	.remove = bq27xxx_battery_i2c_remove,
+	.id_table = bq27xxx_id,
+};
+
+static inline int bq27xxx_battery_i2c_init(void)
+{
+	int ret = i2c_add_driver(&bq27xxx_battery_i2c_driver);
+
+	if (ret)
+		pr_err("Unable to register BQ27xxx i2c driver\n");
+
+	return ret;
+}
+
+static inline void bq27xxx_battery_i2c_exit(void)
+{
+	i2c_del_driver(&bq27xxx_battery_i2c_driver);
+}
+
+#else
+
+static inline int bq27xxx_battery_i2c_init(void) { return 0; }
+static inline void bq27xxx_battery_i2c_exit(void) {};
+
+#endif
+
+/* platform specific code */
+#ifdef CONFIG_BATTERY_BQ27XXX_PLATFORM
+
+static int bq27xxx_battery_platform_read(struct bq27xxx_device_info *di, u8 reg,
+					 bool single)
+{
+	struct device *dev = di->dev;
+	struct bq27xxx_platform_data *pdata = dev->platform_data;
+	unsigned int timeout = 3;
+	int upper, lower;
+	int temp;
+
+	if (!single) {
+		/* Make sure the value has not changed in between reading the
+		 * lower and the upper part */
+		upper = pdata->read(dev, reg + 1);
+		do {
+			temp = upper;
+			if (upper < 0)
+				return upper;
+
+			lower = pdata->read(dev, reg);
+			if (lower < 0)
+				return lower;
+
+			upper = pdata->read(dev, reg + 1);
+		} while (temp != upper && --timeout);
+
+		if (timeout == 0)
+			return -EIO;
+
+		return (upper << 8) | lower;
+	}
+
+	return pdata->read(dev, reg);
+}
+
+static int bq27xxx_battery_platform_probe(struct platform_device *pdev)
+{
+	struct bq27xxx_device_info *di;
+	struct bq27xxx_platform_data *pdata = pdev->dev.platform_data;
+	const char *name;
+
+	if (!pdata) {
+		dev_err(&pdev->dev, "no platform_data supplied\n");
+		return -EINVAL;
+	}
+
+	if (!pdata->read) {
+		dev_err(&pdev->dev, "no hdq read callback supplied\n");
+		return -EINVAL;
+	}
+
+	if (!pdata->chip) {
+		dev_err(&pdev->dev, "no device supplied\n");
+		return -EINVAL;
+	}
+
+	di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
+	if (!di)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, di);
+
+	di->dev = &pdev->dev;
+	di->chip = pdata->chip;
+	di->regs = bq27xxx_regs[di->chip];
+
+	name = pdata->name ?: dev_name(&pdev->dev);
+	di->bus.read = &bq27xxx_battery_platform_read;
+
+	return bq27xxx_powersupply_init(di, name);
+}
+
+static int bq27xxx_battery_platform_remove(struct platform_device *pdev)
+{
+	struct bq27xxx_device_info *di = platform_get_drvdata(pdev);
+
+	bq27xxx_powersupply_unregister(di);
+
+	return 0;
+}
+
+static struct platform_driver bq27xxx_battery_platform_driver = {
+	.probe	= bq27xxx_battery_platform_probe,
+	.remove = bq27xxx_battery_platform_remove,
+	.driver = {
+		.name = "bq27000-battery",
+	},
+};
+
+static inline int bq27xxx_battery_platform_init(void)
+{
+	int ret = platform_driver_register(&bq27xxx_battery_platform_driver);
+
+	if (ret)
+		pr_err("Unable to register BQ27xxx platform driver\n");
+
+	return ret;
+}
+
+static inline void bq27xxx_battery_platform_exit(void)
+{
+	platform_driver_unregister(&bq27xxx_battery_platform_driver);
+}
+
+#else
+
+static inline int bq27xxx_battery_platform_init(void) { return 0; }
+static inline void bq27xxx_battery_platform_exit(void) {};
+
+#endif
+
+/*
+ * Module stuff
+ */
+
+static int __init bq27xxx_battery_init(void)
+{
+	int ret;
+
+	ret = bq27xxx_battery_i2c_init();
+	if (ret)
+		return ret;
+
+	ret = bq27xxx_battery_platform_init();
+	if (ret)
+		bq27xxx_battery_i2c_exit();
+
+	return ret;
+}
+module_init(bq27xxx_battery_init);
+
+static void __exit bq27xxx_battery_exit(void)
+{
+	bq27xxx_battery_platform_exit();
+	bq27xxx_battery_i2c_exit();
+}
+module_exit(bq27xxx_battery_exit);
+
+#ifdef CONFIG_BATTERY_BQ27XXX_PLATFORM
+MODULE_ALIAS("platform:bq27000-battery");
+#endif
+
+MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
+MODULE_DESCRIPTION("BQ27xxx battery monitor driver");
+MODULE_LICENSE("GPL");