power: bq27x00_battery: Renaming for consistency

Rename functions that are used by multiple devices. New devices
have been added and the function names and driver name are no longer
general enough for the functionality they provide.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: GUAN Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

1 files changed, 1126 insertions, 0 deletions

diff --git a/drivers/power/bq27xxx_battery.c b/drivers/power/bq27xxx_battery.c
new file mode 100644
index 000000000000..e72055ce7b3c
--- /dev/null
+++ b/drivers/power/bq27xxx_battery.c
@@ -0,0 +1,1126 @@
+/*
+ * 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://focus.ti.com/docs/prod/folders/print/bq27000.html
+ * http://focus.ti.com/docs/prod/folders/print/bq27500.html
+ * http://www.ti.com/product/bq27425-g1
+ * http://www.ti.com/product/BQ27742-G1
+ * http://www.ti.com/product/BQ27510-G3
+ */
+
+#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 <asm/unaligned.h>
+
+#include <linux/power/bq27xxx_battery.h>
+
+#define DRIVER_VERSION		"1.2.0"
+
+#define BQ27XXX_MANUFACTURER	"Texas Instruments"
+
+#define BQ27x00_REG_TEMP	0x06
+#define BQ27x00_REG_VOLT	0x08
+#define BQ27x00_REG_AI		0x14
+#define BQ27x00_REG_FLAGS	0x0A
+#define BQ27x00_REG_TTE		0x16
+#define BQ27x00_REG_TTF		0x18
+#define BQ27x00_REG_TTECP	0x26
+#define BQ27x00_REG_NAC		0x0C /* Nominal available capacity */
+#define BQ27x00_REG_LMD		0x12 /* Last measured discharge */
+#define BQ27x00_REG_CYCT	0x2A /* Cycle count total */
+#define BQ27x00_REG_AE		0x22 /* Available energy */
+#define BQ27x00_POWER_AVG	0x24
+
+#define BQ27000_REG_RSOC	0x0B /* Relative State-of-Charge */
+#define BQ27000_REG_ILMD	0x76 /* Initial last measured discharge */
+#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 BQ27500_REG_SOC		0x2C
+#define BQ27500_REG_DCAP	0x3C /* Design capacity */
+#define BQ27500_FLAG_DSC	BIT(0)
+#define BQ27500_FLAG_SOCF	BIT(1) /* State-of-Charge threshold final */
+#define BQ27500_FLAG_SOC1	BIT(2) /* State-of-Charge threshold 1 */
+#define BQ27500_FLAG_FC		BIT(9)
+#define BQ27500_FLAG_OTC	BIT(15)
+
+#define BQ27742_POWER_AVG	0x76
+
+#define BQ27510_REG_SOC		0x20
+#define BQ27510_REG_DCAP	0x2E /* Design capacity */
+#define BQ27510_REG_CYCT	0x1E /* Cycle count total */
+
+/* bq27425 register addresses are same as bq27x00 addresses minus 4 */
+#define BQ27425_REG_OFFSET	0x04
+#define BQ27425_REG_SOC		(0x1C + BQ27425_REG_OFFSET)
+#define BQ27425_REG_DCAP	(0x3C + BQ27425_REG_OFFSET)
+
+#define BQ27XXX_RS			20 /* Resistor sense */
+#define BQ27XXX_POWER_CONSTANT		(256 * 29200 / 1000)
+
+struct bq27xxx_device_info;
+struct bq27xxx_access_methods {
+	int (*read)(struct bq27xxx_device_info *di, u8 reg, bool single);
+};
+
+enum bq27xxx_chip { BQ27000, BQ27500, BQ27425, BQ27742, BQ27510};
+
+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;
+};
+
+static enum power_supply_property bq27x00_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 bq27425_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,
+};
+
+static enum power_supply_property bq27742_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 bq27510_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 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, u8 reg,
+			       bool single)
+{
+	if (di->chip == BQ27425)
+		return di->bus.read(di, reg - BQ27425_REG_OFFSET, single);
+	return di->bus.read(di, reg, single);
+}
+
+/*
+ * Higher versions of the chip like BQ27425 and BQ27500
+ * differ from BQ27000 and BQ27200 in calculation of certain
+ * parameters. Hence we need to check for the chip type.
+ */
+static bool bq27xxx_is_chip_version_higher(struct bq27xxx_device_info *di)
+{
+	if (di->chip == BQ27425 || di->chip == BQ27500 || di->chip == BQ27742
+	    || di->chip == BQ27510)
+		return true;
+	return false;
+}
+
+/*
+ * Return the battery Relative State-of-Charge
+ * Or < 0 if something fails.
+ */
+static int bq27xxx_battery_read_rsoc(struct bq27xxx_device_info *di)
+{
+	int rsoc;
+
+	if (di->chip == BQ27500 || di->chip == BQ27742)
+		rsoc = bq27xxx_read(di, BQ27500_REG_SOC, false);
+	else if (di->chip == BQ27510)
+		rsoc = bq27xxx_read(di, BQ27510_REG_SOC, false);
+	else if (di->chip == BQ27425)
+		rsoc = bq27xxx_read(di, BQ27425_REG_SOC, false);
+	else
+		rsoc = bq27xxx_read(di, BQ27000_REG_RSOC, true);
+
+	if (rsoc < 0)
+		dev_dbg(di->dev, "error reading relative State-of-Charge\n");
+
+	return rsoc;
+}
+
+/*
+ * 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 (bq27xxx_is_chip_version_higher(di))
+		charge *= 1000;
+	else
+		charge = charge * 3570 / BQ27XXX_RS;
+
+	return charge;
+}
+
+/*
+ * Return the battery Nominal available capaciy in µAh
+ * Or < 0 if something fails.
+ */
+static inline int bq27xxx_battery_read_nac(struct bq27xxx_device_info *di)
+{
+	int flags;
+	bool is_bq27500 = di->chip == BQ27500;
+	bool is_bq27742 = di->chip == BQ27742;
+	bool is_higher = bq27xxx_is_chip_version_higher(di);
+	bool flags_1b = !(is_bq27500 || is_bq27742);
+
+	flags = bq27xxx_read(di, BQ27x00_REG_FLAGS, flags_1b);
+	if (flags >= 0 && !is_higher && (flags & BQ27000_FLAG_CI))
+		return -ENODATA;
+
+	return bq27xxx_battery_read_charge(di, BQ27x00_REG_NAC);
+}
+
+/*
+ * Return the battery Last measured discharge in µAh
+ * Or < 0 if something fails.
+ */
+static inline int bq27xxx_battery_read_lmd(struct bq27xxx_device_info *di)
+{
+	return bq27xxx_battery_read_charge(di, BQ27x00_REG_LMD);
+}
+
+/*
+ * Return the battery Initial last measured discharge in µAh
+ * Or < 0 if something fails.
+ */
+static int bq27xxx_battery_read_ilmd(struct bq27xxx_device_info *di)
+{
+	int ilmd;
+
+	if (bq27xxx_is_chip_version_higher(di)) {
+		if (di->chip == BQ27425)
+			ilmd = bq27xxx_read(di, BQ27425_REG_DCAP, false);
+		else if (di->chip == BQ27510)
+			ilmd = bq27xxx_read(di, BQ27510_REG_DCAP, false);
+		else
+			ilmd = bq27xxx_read(di, BQ27500_REG_DCAP, false);
+	} else {
+		ilmd = bq27xxx_read(di, BQ27000_REG_ILMD, true);
+	}
+
+	if (ilmd < 0) {
+		dev_dbg(di->dev, "error reading initial last measured discharge\n");
+		return ilmd;
+	}
+
+	if (bq27xxx_is_chip_version_higher(di))
+		ilmd *= 1000;
+	else
+		ilmd = ilmd * 256 * 3570 / BQ27XXX_RS;
+
+	return ilmd;
+}
+
+/*
+ * 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, BQ27x00_REG_AE, false);
+	if (ae < 0) {
+		dev_dbg(di->dev, "error reading available energy\n");
+		return ae;
+	}
+
+	if (di->chip == BQ27500)
+		ae *= 1000;
+	else
+		ae = ae * 29200 / BQ27XXX_RS;
+
+	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, BQ27x00_REG_TEMP, false);
+	if (temp < 0) {
+		dev_err(di->dev, "error reading temperature\n");
+		return temp;
+	}
+
+	if (!bq27xxx_is_chip_version_higher(di))
+		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;
+
+	if (di->chip == BQ27510)
+		cyct = bq27xxx_read(di, BQ27510_REG_CYCT, false);
+	else
+		cyct = bq27xxx_read(di, BQ27x00_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 a power avg register.
+ * Return < 0 if something fails.
+ */
+static int bq27xxx_battery_read_pwr_avg(struct bq27xxx_device_info *di, u8 reg)
+{
+	int tval;
+
+	tval = bq27xxx_read(di, reg, false);
+	if (tval < 0) {
+		dev_err(di->dev, "error reading power avg rgister  %02x: %d\n",
+			reg, tval);
+		return tval;
+	}
+
+	if (di->chip == BQ27500)
+		return tval;
+	else
+		return (tval * BQ27XXX_POWER_CONSTANT) / BQ27XXX_RS;
+}
+
+/*
+ * Read flag register.
+ * Return < 0 if something fails.
+ */
+static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
+{
+	int tval;
+
+	tval = bq27xxx_read(di, BQ27x00_REG_FLAGS, false);
+	if (tval < 0) {
+		dev_err(di->dev, "error reading flag register:%d\n", tval);
+		return tval;
+	}
+
+	if (di->chip == BQ27500) {
+		if (tval & BQ27500_FLAG_SOCF)
+			tval = POWER_SUPPLY_HEALTH_DEAD;
+		else if (tval & BQ27500_FLAG_OTC)
+			tval = POWER_SUPPLY_HEALTH_OVERHEAT;
+		else
+			tval = POWER_SUPPLY_HEALTH_GOOD;
+		return tval;
+	} else if (di->chip == BQ27510) {
+		if (tval & BQ27500_FLAG_OTC)
+			return POWER_SUPPLY_HEALTH_OVERHEAT;
+		return POWER_SUPPLY_HEALTH_GOOD;
+	} else {
+		if (tval & BQ27000_FLAG_EDV1)
+			tval = POWER_SUPPLY_HEALTH_DEAD;
+		else
+			tval = POWER_SUPPLY_HEALTH_GOOD;
+		return tval;
+	}
+
+	return -1;
+}
+
+static void bq27xxx_battery_update(struct bq27xxx_device_info *di)
+{
+	struct bq27xxx_reg_cache cache = {0, };
+	bool is_bq27500 = di->chip == BQ27500;
+	bool is_bq27510 = di->chip == BQ27510;
+	bool is_bq27425 = di->chip == BQ27425;
+	bool is_bq27742 = di->chip == BQ27742;
+	bool flags_1b = !(is_bq27500 || is_bq27742);
+
+	cache.flags = bq27xxx_read(di, BQ27x00_REG_FLAGS, flags_1b);
+	if ((cache.flags & 0xff) == 0xff)
+		/* read error */
+		cache.flags = -1;
+	if (cache.flags >= 0) {
+		if (!is_bq27500 && !is_bq27425 && !is_bq27742 && !is_bq27510
+				&& (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 {
+			cache.capacity = bq27xxx_battery_read_rsoc(di);
+			if (is_bq27742 || is_bq27510)
+				cache.time_to_empty =
+					bq27xxx_battery_read_time(di,
+							BQ27x00_REG_TTE);
+			else if (!is_bq27425) {
+				cache.energy = bq27xxx_battery_read_energy(di);
+				cache.time_to_empty =
+					bq27xxx_battery_read_time(di,
+							BQ27x00_REG_TTE);
+				cache.time_to_empty_avg =
+					bq27xxx_battery_read_time(di,
+							BQ27x00_REG_TTECP);
+				cache.time_to_full =
+					bq27xxx_battery_read_time(di,
+							BQ27x00_REG_TTF);
+			}
+			cache.charge_full = bq27xxx_battery_read_lmd(di);
+			cache.health = bq27xxx_battery_read_health(di);
+		}
+		cache.temperature = bq27xxx_battery_read_temperature(di);
+		if (!is_bq27425)
+			cache.cycle_count = bq27xxx_battery_read_cyct(di);
+		if (is_bq27742)
+			cache.power_avg =
+				bq27xxx_battery_read_pwr_avg(di,
+						BQ27742_POWER_AVG);
+		else
+			cache.power_avg =
+				bq27xxx_battery_read_pwr_avg(di,
+						BQ27x00_POWER_AVG);
+
+		/* We only have to read charge design full once */
+		if (di->charge_design_full <= 0)
+			di->charge_design_full = bq27xxx_battery_read_ilmd(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, BQ27x00_REG_AI, false);
+	if (curr < 0) {
+		dev_err(di->dev, "error reading current\n");
+		return curr;
+	}
+
+	if (bq27xxx_is_chip_version_higher(di)) {
+		/* bq27500 returns signed value */
+		val->intval = (int)((s16)curr) * 1000;
+	} else {
+		flags = bq27xxx_read(di, BQ27x00_REG_FLAGS, false);
+		if (flags & BQ27000_FLAG_CHGS) {
+			dev_dbg(di->dev, "negative current!\n");
+			curr = -curr;
+		}
+
+		val->intval = curr * 3570 / BQ27XXX_RS;
+	}
+
+	return 0;
+}
+
+static int bq27xxx_battery_status(struct bq27xxx_device_info *di,
+				  union power_supply_propval *val)
+{
+	int status;
+
+	if (bq27xxx_is_chip_version_higher(di)) {
+		if (di->cache.flags & BQ27500_FLAG_FC)
+			status = POWER_SUPPLY_STATUS_FULL;
+		else if (di->cache.flags & BQ27500_FLAG_DSC)
+			status = POWER_SUPPLY_STATUS_DISCHARGING;
+		else
+			status = POWER_SUPPLY_STATUS_CHARGING;
+	} else {
+		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;
+	}
+
+	val->intval = status;
+
+	return 0;
+}
+
+static int bq27xxx_battery_capacity_level(struct bq27xxx_device_info *di,
+					  union power_supply_propval *val)
+{
+	int level;
+
+	if (bq27xxx_is_chip_version_higher(di)) {
+		if (di->cache.flags & BQ27500_FLAG_FC)
+			level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
+		else if (di->cache.flags & BQ27500_FLAG_SOC1)
+			level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
+		else if (di->cache.flags & BQ27500_FLAG_SOCF)
+			level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
+		else
+			level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
+	} else {
+		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;
+	}
+
+	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, BQ27x00_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;
+		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;
+	if (di->chip == BQ27425) {
+		psy_desc->properties = bq27425_battery_props;
+		psy_desc->num_properties = ARRAY_SIZE(bq27425_battery_props);
+	} else if (di->chip == BQ27742) {
+		psy_desc->properties = bq27742_battery_props;
+		psy_desc->num_properties = ARRAY_SIZE(bq27742_battery_props);
+	} else if (di->chip == BQ27510) {
+		psy_desc->properties = bq27510_battery_props;
+		psy_desc->num_properties = ARRAY_SIZE(bq27510_battery_props);
+	} else {
+		psy_desc->properties = bq27x00_battery_props;
+		psy_desc->num_properties = ARRAY_SIZE(bq27x00_battery_props);
+	}
+	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 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;
+
+	retval = bq27xxx_powersupply_init(di, name);
+	if (retval)
+		goto batt_failed;
+
+	i2c_set_clientdata(client, di);
+
+	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 },	/* bq27200 is same as bq27000, but with i2c */
+	{ "bq27500", BQ27500 },
+	{ "bq27425", BQ27425 },
+	{ "bq27742", BQ27742 },
+	{ "bq27510", BQ27510 },
+	{},
+};
+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;
+	}
+
+	di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
+	if (!di)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, di);
+
+	di->dev = &pdev->dev;
+	di->chip = BQ27000;
+
+	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");