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Diffstat (limited to 'drivers/power/bq27xxx_battery.c')
-rw-r--r--drivers/power/bq27xxx_battery.c1375
1 files changed, 1375 insertions, 0 deletions
diff --git a/drivers/power/bq27xxx_battery.c b/drivers/power/bq27xxx_battery.c
new file mode 100644
index 000000000..880233ce9
--- /dev/null
+++ b/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");