power_supply: Add bq2415x charger driver

The bq2415x charger driver is needed for example on Nokia N900 for
charging battery. Driver is part of open source project to replace
proprietary battery management.

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>

1 files changed, 1644 insertions, 0 deletions

diff --git a/drivers/power/bq2415x_charger.c b/drivers/power/bq2415x_charger.c
new file mode 100644
index 00000000000..017b3c27f76
--- /dev/null
+++ b/drivers/power/bq2415x_charger.c
@@ -0,0 +1,1644 @@
+/*
+    bq2415x_charger.c - bq2415x charger driver
+    Copyright (C) 2011-2012  Pali Rohár <pali.rohar@gmail.com>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+/*
+  Datasheets:
+  http://www.ti.com/product/bq24150
+  http://www.ti.com/product/bq24150a
+  http://www.ti.com/product/bq24152
+  http://www.ti.com/product/bq24153
+  http://www.ti.com/product/bq24153a
+  http://www.ti.com/product/bq24155
+*/
+
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/param.h>
+#include <linux/err.h>
+#include <linux/workqueue.h>
+#include <linux/sysfs.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/power/bq2415x_charger.h>
+
+/* timeout for resetting chip timer */
+#define BQ2415X_TIMER_TIMEOUT		10
+
+#define BQ2415X_REG_STATUS		0x00
+#define BQ2415X_REG_CONTROL		0x01
+#define BQ2415X_REG_VOLTAGE		0x02
+#define BQ2415X_REG_VENDER		0x03
+#define BQ2415X_REG_CURRENT		0x04
+
+/* reset state for all registers */
+#define BQ2415X_RESET_STATUS		BIT(6)
+#define BQ2415X_RESET_CONTROL		(BIT(4)|BIT(5))
+#define BQ2415X_RESET_VOLTAGE		(BIT(1)|BIT(3))
+#define BQ2415X_RESET_CURRENT		(BIT(0)|BIT(3)|BIT(7))
+
+/* status register */
+#define BQ2415X_BIT_TMR_RST		7
+#define BQ2415X_BIT_OTG			7
+#define BQ2415X_BIT_EN_STAT		6
+#define BQ2415X_MASK_STAT		(BIT(4)|BIT(5))
+#define BQ2415X_SHIFT_STAT		4
+#define BQ2415X_BIT_BOOST		3
+#define BQ2415X_MASK_FAULT		(BIT(0)|BIT(1)|BIT(2))
+#define BQ2415X_SHIFT_FAULT		0
+
+/* control register */
+#define BQ2415X_MASK_LIMIT		(BIT(6)|BIT(7))
+#define BQ2415X_SHIFT_LIMIT		6
+#define BQ2415X_MASK_VLOWV		(BIT(4)|BIT(5))
+#define BQ2415X_SHIFT_VLOWV		4
+#define BQ2415X_BIT_TE			3
+#define BQ2415X_BIT_CE			2
+#define BQ2415X_BIT_HZ_MODE		1
+#define BQ2415X_BIT_OPA_MODE		0
+
+/* voltage register */
+#define BQ2415X_MASK_VO		(BIT(2)|BIT(3)|BIT(4)|BIT(5)|BIT(6)|BIT(7))
+#define BQ2415X_SHIFT_VO		2
+#define BQ2415X_BIT_OTG_PL		1
+#define BQ2415X_BIT_OTG_EN		0
+
+/* vender register */
+#define BQ2415X_MASK_VENDER		(BIT(5)|BIT(6)|BIT(7))
+#define BQ2415X_SHIFT_VENDER		5
+#define BQ2415X_MASK_PN			(BIT(3)|BIT(4))
+#define BQ2415X_SHIFT_PN		3
+#define BQ2415X_MASK_REVISION		(BIT(0)|BIT(1)|BIT(2))
+#define BQ2415X_SHIFT_REVISION		0
+
+/* current register */
+#define BQ2415X_MASK_RESET		BIT(7)
+#define BQ2415X_MASK_VI_CHRG		(BIT(4)|BIT(5)|BIT(6))
+#define BQ2415X_SHIFT_VI_CHRG		4
+/* N/A					BIT(3) */
+#define BQ2415X_MASK_VI_TERM		(BIT(0)|BIT(1)|BIT(2))
+#define BQ2415X_SHIFT_VI_TERM		0
+
+
+enum bq2415x_command {
+	BQ2415X_TIMER_RESET,
+	BQ2415X_OTG_STATUS,
+	BQ2415X_STAT_PIN_STATUS,
+	BQ2415X_STAT_PIN_ENABLE,
+	BQ2415X_STAT_PIN_DISABLE,
+	BQ2415X_CHARGE_STATUS,
+	BQ2415X_BOOST_STATUS,
+	BQ2415X_FAULT_STATUS,
+
+	BQ2415X_CHARGE_TERMINATION_STATUS,
+	BQ2415X_CHARGE_TERMINATION_ENABLE,
+	BQ2415X_CHARGE_TERMINATION_DISABLE,
+	BQ2415X_CHARGER_STATUS,
+	BQ2415X_CHARGER_ENABLE,
+	BQ2415X_CHARGER_DISABLE,
+	BQ2415X_HIGH_IMPEDANCE_STATUS,
+	BQ2415X_HIGH_IMPEDANCE_ENABLE,
+	BQ2415X_HIGH_IMPEDANCE_DISABLE,
+	BQ2415X_BOOST_MODE_STATUS,
+	BQ2415X_BOOST_MODE_ENABLE,
+	BQ2415X_BOOST_MODE_DISABLE,
+
+	BQ2415X_OTG_LEVEL,
+	BQ2415X_OTG_ACTIVATE_HIGH,
+	BQ2415X_OTG_ACTIVATE_LOW,
+	BQ2415X_OTG_PIN_STATUS,
+	BQ2415X_OTG_PIN_ENABLE,
+	BQ2415X_OTG_PIN_DISABLE,
+
+	BQ2415X_VENDER_CODE,
+	BQ2415X_PART_NUMBER,
+	BQ2415X_REVISION,
+};
+
+enum bq2415x_chip {
+	BQUNKNOWN,
+	BQ24150,
+	BQ24150A,
+	BQ24151,
+	BQ24151A,
+	BQ24152,
+	BQ24153,
+	BQ24153A,
+	BQ24155,
+	BQ24156,
+	BQ24156A,
+	BQ24158,
+};
+
+static char *bq2415x_chip_name[] = {
+	"unknown",
+	"bq24150",
+	"bq24150a",
+	"bq24151",
+	"bq24151a",
+	"bq24152",
+	"bq24153",
+	"bq24153a",
+	"bq24155",
+	"bq24156",
+	"bq24156a",
+	"bq24158",
+};
+
+struct bq2415x_device {
+	struct device *dev;
+	struct bq2415x_platform_data init_data;
+	struct power_supply charger;
+	struct delayed_work work;
+	enum bq2415x_mode reported_mode;/* mode reported by hook function */
+	enum bq2415x_mode mode;		/* current configured mode */
+	enum bq2415x_chip chip;
+	const char *timer_error;
+	char *model;
+	char *name;
+	int autotimer;	/* 1 - if driver automatically reset timer, 0 - not */
+	int automode;	/* 1 - enabled, 0 - disabled; -1 - not supported */
+	int id;
+};
+
+/* each registered chip must have unique id */
+static DEFINE_IDR(bq2415x_id);
+
+static DEFINE_MUTEX(bq2415x_id_mutex);
+static DEFINE_MUTEX(bq2415x_timer_mutex);
+static DEFINE_MUTEX(bq2415x_i2c_mutex);
+
+/**** i2c read functions ****/
+
+/* read value from register */
+static int bq2415x_i2c_read(struct bq2415x_device *bq, u8 reg)
+{
+	struct i2c_client *client = to_i2c_client(bq->dev);
+	struct i2c_msg msg[2];
+	u8 val;
+	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 = &val;
+	msg[1].len = sizeof(val);
+
+	mutex_lock(&bq2415x_i2c_mutex);
+	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
+	mutex_unlock(&bq2415x_i2c_mutex);
+
+	if (ret < 0)
+		return ret;
+
+	return val;
+}
+
+/* read value from register, apply mask and right shift it */
+static int bq2415x_i2c_read_mask(struct bq2415x_device *bq, u8 reg,
+				u8 mask, u8 shift)
+{
+	int ret;
+
+	if (shift > 8)
+		return -EINVAL;
+
+	ret = bq2415x_i2c_read(bq, reg);
+	if (ret < 0)
+		return ret;
+	else
+		return (ret & mask) >> shift;
+}
+
+/* read value from register and return one specified bit */
+static int bq2415x_i2c_read_bit(struct bq2415x_device *bq, u8 reg, u8 bit)
+{
+	if (bit > 8)
+		return -EINVAL;
+	else
+		return bq2415x_i2c_read_mask(bq, reg, BIT(bit), bit);
+}
+
+/**** i2c write functions ****/
+
+/* write value to register */
+static int bq2415x_i2c_write(struct bq2415x_device *bq, u8 reg, u8 val)
+{
+	struct i2c_client *client = to_i2c_client(bq->dev);
+	struct i2c_msg msg[1];
+	u8 data[2];
+	int ret;
+
+	data[0] = reg;
+	data[1] = val;
+
+	msg[0].addr = client->addr;
+	msg[0].flags = 0;
+	msg[0].buf = data;
+	msg[0].len = ARRAY_SIZE(data);
+
+	mutex_lock(&bq2415x_i2c_mutex);
+	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
+	mutex_unlock(&bq2415x_i2c_mutex);
+
+	/* i2c_transfer returns number of messages transferred */
+	if (ret < 0)
+		return ret;
+	else if (ret != 1)
+		return -EIO;
+
+	return 0;
+}
+
+/* read value from register, change it with mask left shifted and write back */
+static int bq2415x_i2c_write_mask(struct bq2415x_device *bq, u8 reg, u8 val,
+				u8 mask, u8 shift)
+{
+	int ret;
+
+	if (shift > 8)
+		return -EINVAL;
+
+	ret = bq2415x_i2c_read(bq, reg);
+	if (ret < 0)
+		return ret;
+
+	ret &= ~mask;
+	ret |= val << shift;
+
+	return bq2415x_i2c_write(bq, reg, ret);
+}
+
+/* change only one bit in register */
+static int bq2415x_i2c_write_bit(struct bq2415x_device *bq, u8 reg,
+				bool val, u8 bit)
+{
+	if (bit > 8)
+		return -EINVAL;
+	else
+		return bq2415x_i2c_write_mask(bq, reg, val, BIT(bit), bit);
+}
+
+/**** global functions ****/
+
+/* exec command function */
+static int bq2415x_exec_command(struct bq2415x_device *bq,
+				enum bq2415x_command command)
+{
+	int ret;
+	switch (command) {
+	case BQ2415X_TIMER_RESET:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_STATUS,
+				1, BQ2415X_BIT_TMR_RST);
+	case BQ2415X_OTG_STATUS:
+		return bq2415x_i2c_read_bit(bq, BQ2415X_REG_STATUS,
+				BQ2415X_BIT_OTG);
+	case BQ2415X_STAT_PIN_STATUS:
+		return bq2415x_i2c_read_bit(bq, BQ2415X_REG_STATUS,
+				BQ2415X_BIT_EN_STAT);
+	case BQ2415X_STAT_PIN_ENABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_STATUS, 1,
+				BQ2415X_BIT_EN_STAT);
+	case BQ2415X_STAT_PIN_DISABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_STATUS, 0,
+				BQ2415X_BIT_EN_STAT);
+	case BQ2415X_CHARGE_STATUS:
+		return bq2415x_i2c_read_mask(bq, BQ2415X_REG_STATUS,
+				BQ2415X_MASK_STAT, BQ2415X_SHIFT_STAT);
+	case BQ2415X_BOOST_STATUS:
+		return bq2415x_i2c_read_bit(bq, BQ2415X_REG_STATUS,
+				BQ2415X_BIT_BOOST);
+	case BQ2415X_FAULT_STATUS:
+		return bq2415x_i2c_read_mask(bq, BQ2415X_REG_STATUS,
+			BQ2415X_MASK_FAULT, BQ2415X_SHIFT_FAULT);
+
+	case BQ2415X_CHARGE_TERMINATION_STATUS:
+		return bq2415x_i2c_read_bit(bq, BQ2415X_REG_CONTROL,
+				BQ2415X_BIT_TE);
+	case BQ2415X_CHARGE_TERMINATION_ENABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_CONTROL,
+				1, BQ2415X_BIT_TE);
+	case BQ2415X_CHARGE_TERMINATION_DISABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_CONTROL,
+				0, BQ2415X_BIT_TE);
+	case BQ2415X_CHARGER_STATUS:
+		ret = bq2415x_i2c_read_bit(bq, BQ2415X_REG_CONTROL,
+			BQ2415X_BIT_CE);
+		if (ret < 0)
+			return ret;
+		else
+			return ret > 0 ? 0 : 1;
+	case BQ2415X_CHARGER_ENABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_CONTROL,
+				0, BQ2415X_BIT_CE);
+	case BQ2415X_CHARGER_DISABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_CONTROL,
+				1, BQ2415X_BIT_CE);
+	case BQ2415X_HIGH_IMPEDANCE_STATUS:
+		return bq2415x_i2c_read_bit(bq, BQ2415X_REG_CONTROL,
+				BQ2415X_BIT_HZ_MODE);
+	case BQ2415X_HIGH_IMPEDANCE_ENABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_CONTROL,
+				1, BQ2415X_BIT_HZ_MODE);
+	case BQ2415X_HIGH_IMPEDANCE_DISABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_CONTROL,
+				0, BQ2415X_BIT_HZ_MODE);
+	case BQ2415X_BOOST_MODE_STATUS:
+		return bq2415x_i2c_read_bit(bq, BQ2415X_REG_CONTROL,
+				BQ2415X_BIT_OPA_MODE);
+	case BQ2415X_BOOST_MODE_ENABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_CONTROL,
+				1, BQ2415X_BIT_OPA_MODE);
+	case BQ2415X_BOOST_MODE_DISABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_CONTROL,
+				0, BQ2415X_BIT_OPA_MODE);
+
+	case BQ2415X_OTG_LEVEL:
+		return bq2415x_i2c_read_bit(bq, BQ2415X_REG_VOLTAGE,
+				BQ2415X_BIT_OTG_PL);
+	case BQ2415X_OTG_ACTIVATE_HIGH:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_VOLTAGE,
+				1, BQ2415X_BIT_OTG_PL);
+	case BQ2415X_OTG_ACTIVATE_LOW:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_VOLTAGE,
+				0, BQ2415X_BIT_OTG_PL);
+	case BQ2415X_OTG_PIN_STATUS:
+		return bq2415x_i2c_read_bit(bq, BQ2415X_REG_VOLTAGE,
+				BQ2415X_BIT_OTG_EN);
+	case BQ2415X_OTG_PIN_ENABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_VOLTAGE,
+				1, BQ2415X_BIT_OTG_EN);
+	case BQ2415X_OTG_PIN_DISABLE:
+		return bq2415x_i2c_write_bit(bq, BQ2415X_REG_VOLTAGE,
+				0, BQ2415X_BIT_OTG_EN);
+
+	case BQ2415X_VENDER_CODE:
+		return bq2415x_i2c_read_mask(bq, BQ2415X_REG_VENDER,
+			BQ2415X_MASK_VENDER, BQ2415X_SHIFT_VENDER);
+	case BQ2415X_PART_NUMBER:
+		return bq2415x_i2c_read_mask(bq, BQ2415X_REG_VENDER,
+				BQ2415X_MASK_PN, BQ2415X_SHIFT_PN);
+	case BQ2415X_REVISION:
+		return bq2415x_i2c_read_mask(bq, BQ2415X_REG_VENDER,
+			BQ2415X_MASK_REVISION, BQ2415X_SHIFT_REVISION);
+
+	default:
+		return -EINVAL;
+	}
+}
+
+/* detect chip type */
+static enum bq2415x_chip bq2415x_detect_chip(struct bq2415x_device *bq)
+{
+	struct i2c_client *client = to_i2c_client(bq->dev);
+	int ret = bq2415x_exec_command(bq, BQ2415X_PART_NUMBER);
+
+	if (ret < 0)
+		return ret;
+
+	switch (client->addr) {
+	case 0x6b:
+		switch (ret) {
+		case 0:
+			if (bq->chip == BQ24151A)
+				return bq->chip;
+			else
+				return BQ24151;
+		case 1:
+			if (bq->chip == BQ24150A ||
+				bq->chip == BQ24152 ||
+				bq->chip == BQ24155)
+				return bq->chip;
+			else
+				return BQ24150;
+		case 2:
+			if (bq->chip == BQ24153A)
+				return bq->chip;
+			else
+				return BQ24153;
+		default:
+			return BQUNKNOWN;
+		}
+		break;
+
+	case 0x6a:
+		switch (ret) {
+		case 0:
+			if (bq->chip == BQ24156A)
+				return bq->chip;
+			else
+				return BQ24156;
+		case 2:
+			return BQ24158;
+		default:
+			return BQUNKNOWN;
+		}
+		break;
+	}
+
+	return BQUNKNOWN;
+}
+
+/* detect chip revision */
+static int bq2415x_detect_revision(struct bq2415x_device *bq)
+{
+	int ret = bq2415x_exec_command(bq, BQ2415X_REVISION);
+	int chip = bq2415x_detect_chip(bq);
+	if (ret < 0 || chip < 0)
+		return -1;
+
+	switch (chip) {
+	case BQ24150:
+	case BQ24150A:
+	case BQ24151:
+	case BQ24151A:
+	case BQ24152:
+		if (ret >= 0 && ret <= 3)
+			return ret;
+		else
+			return -1;
+
+	case BQ24153:
+	case BQ24153A:
+	case BQ24156:
+	case BQ24156A:
+	case BQ24158:
+		if (ret == 3)
+			return 0;
+		else if (ret == 1)
+			return 1;
+		else
+			return -1;
+
+	case BQ24155:
+		if (ret == 3)
+			return 3;
+		else
+			return -1;
+
+	case BQUNKNOWN:
+		return -1;
+	}
+
+	return -1;
+}
+
+/* return chip vender code */
+static int bq2415x_get_vender_code(struct bq2415x_device *bq)
+{
+	int ret = bq2415x_exec_command(bq, BQ2415X_VENDER_CODE);
+	if (ret < 0)
+		return 0;
+	else /* convert to binary */
+		return (ret & 0x1) +
+			((ret >> 1) & 0x1) * 10 +
+			((ret >> 2) & 0x1) * 100;
+}
+
+/* reset all chip registers to default state */
+static void bq2415x_reset_chip(struct bq2415x_device *bq)
+{
+	bq2415x_i2c_write(bq, BQ2415X_REG_CURRENT, BQ2415X_RESET_CURRENT);
+	bq2415x_i2c_write(bq, BQ2415X_REG_VOLTAGE, BQ2415X_RESET_VOLTAGE);
+	bq2415x_i2c_write(bq, BQ2415X_REG_CONTROL, BQ2415X_RESET_CONTROL);
+	bq2415x_i2c_write(bq, BQ2415X_REG_STATUS, BQ2415X_RESET_STATUS);
+	bq->timer_error = NULL;
+}
+
+/**** properties functions ****/
+
+/* set current limit in mA */
+static int bq2415x_set_current_limit(struct bq2415x_device *bq, int mA)
+{
+	int val;
+	if (mA <= 100)
+		val = 0;
+	else if (mA <= 500)
+		val = 1;
+	else if (mA <= 800)
+		val = 2;
+	else
+		val = 3;
+	return bq2415x_i2c_write_mask(bq, BQ2415X_REG_CONTROL, val,
+			BQ2415X_MASK_LIMIT, BQ2415X_SHIFT_LIMIT);
+}
+
+/* get current limit in mA */
+static int bq2415x_get_current_limit(struct bq2415x_device *bq)
+{
+	int ret = bq2415x_i2c_read_mask(bq, BQ2415X_REG_CONTROL,
+			BQ2415X_MASK_LIMIT, BQ2415X_SHIFT_LIMIT);
+	if (ret < 0)
+		return ret;
+	else if (ret == 0)
+		return 100;
+	else if (ret == 1)
+		return 500;
+	else if (ret == 2)
+		return 800;
+	else if (ret == 3)
+		return 1800;
+	else
+		return -EINVAL;
+}
+
+/* set weak battery voltage in mV */
+static int bq2415x_set_weak_battery_voltage(struct bq2415x_device *bq, int mV)
+{
+	/* round to 100mV */
+	int val;
+	if (mV <= 3400 + 50)
+		val = 0;
+	else if (mV <= 3500 + 50)
+		val = 1;
+	else if (mV <= 3600 + 50)
+		val = 2;
+	else
+		val = 3;
+	return bq2415x_i2c_write_mask(bq, BQ2415X_REG_CONTROL, val,
+			BQ2415X_MASK_VLOWV, BQ2415X_SHIFT_VLOWV);
+}
+
+/* get weak battery voltage in mV */
+static int bq2415x_get_weak_battery_voltage(struct bq2415x_device *bq)
+{
+	int ret = bq2415x_i2c_read_mask(bq, BQ2415X_REG_CONTROL,
+			BQ2415X_MASK_VLOWV, BQ2415X_SHIFT_VLOWV);
+	if (ret < 0)
+		return ret;
+	else
+		return 100 * (34 + ret);
+}
+
+/* set battery regulation voltage in mV */
+static int bq2415x_set_battery_regulation_voltage(struct bq2415x_device *bq,
+						int mV)
+{
+	int val = (mV/10 - 350) / 2;
+
+	if (val < 0)
+		val = 0;
+	else if (val > 94) /* FIXME: Max is 94 or 122 ? Set max value ? */
+		return -EINVAL;
+
+	return bq2415x_i2c_write_mask(bq, BQ2415X_REG_VOLTAGE, val,
+			BQ2415X_MASK_VO, BQ2415X_SHIFT_VO);
+}
+
+/* get battery regulation voltage in mV */
+static int bq2415x_get_battery_regulation_voltage(struct bq2415x_device *bq)
+{
+	int ret = bq2415x_i2c_read_mask(bq, BQ2415X_REG_VOLTAGE,
+			BQ2415X_MASK_VO, BQ2415X_SHIFT_VO);
+	if (ret < 0)
+		return ret;
+	else
+		return 10 * (350 + 2*ret);
+}
+
+/* set charge current in mA (platform data must provide resistor sense) */
+static int bq2415x_set_charge_current(struct bq2415x_device *bq, int mA)
+{
+	int val;
+	if (bq->init_data.resistor_sense <= 0)
+		return -ENOSYS;
+
+	val = (mA * bq->init_data.resistor_sense - 37400) / 6800;
+
+	if (val < 0)
+		val = 0;
+	else if (val > 7)
+		val = 7;
+
+	return bq2415x_i2c_write_mask(bq, BQ2415X_REG_CURRENT, val,
+			BQ2415X_MASK_VI_CHRG | BQ2415X_MASK_RESET,
+			BQ2415X_SHIFT_VI_CHRG);
+}
+
+/* get charge current in mA (platform data must provide resistor sense) */
+static int bq2415x_get_charge_current(struct bq2415x_device *bq)
+{
+	int ret;
+	if (bq->init_data.resistor_sense <= 0)
+		return -ENOSYS;
+
+	ret = bq2415x_i2c_read_mask(bq, BQ2415X_REG_CURRENT,
+			BQ2415X_MASK_VI_CHRG, BQ2415X_SHIFT_VI_CHRG);
+	if (ret < 0)
+		return ret;
+	else
+		return (37400 + 6800*ret) / bq->init_data.resistor_sense;
+}
+
+/* set termination current in mA (platform data must provide resistor sense) */
+static int bq2415x_set_termination_current(struct bq2415x_device *bq, int mA)
+{
+	int val;
+	if (bq->init_data.resistor_sense <= 0)
+		return -ENOSYS;
+
+	val = (mA * bq->init_data.resistor_sense - 3400) / 3400;
+
+	if (val < 0)
+		val = 0;
+	else if (val > 7)
+		val = 7;
+
+	return bq2415x_i2c_write_mask(bq, BQ2415X_REG_CURRENT, val,
+			BQ2415X_MASK_VI_TERM | BQ2415X_MASK_RESET,
+			BQ2415X_SHIFT_VI_TERM);
+}
+
+/* get termination current in mA (platform data must provide resistor sense) */
+static int bq2415x_get_termination_current(struct bq2415x_device *bq)
+{
+	int ret;
+	if (bq->init_data.resistor_sense <= 0)
+		return -ENOSYS;
+
+	ret = bq2415x_i2c_read_mask(bq, BQ2415X_REG_CURRENT,
+			BQ2415X_MASK_VI_TERM, BQ2415X_SHIFT_VI_TERM);
+	if (ret < 0)
+		return ret;
+	else
+		return (3400 + 3400*ret) / bq->init_data.resistor_sense;
+}
+
+/* set default value of property */
+#define bq2415x_set_default_value(bq, prop) \
+	do { \
+		int ret = 0; \
+		if (bq->init_data.prop != -1) \
+			ret = bq2415x_set_##prop(bq, bq->init_data.prop); \
+		if (ret < 0) \
+			return ret; \
+	} while (0)
+
+/* set default values of all properties */
+static int bq2415x_set_defaults(struct bq2415x_device *bq)
+{
+	bq2415x_exec_command(bq, BQ2415X_BOOST_MODE_DISABLE);
+	bq2415x_exec_command(bq, BQ2415X_CHARGER_DISABLE);
+	bq2415x_exec_command(bq, BQ2415X_CHARGE_TERMINATION_DISABLE);
+	bq2415x_set_default_value(bq, current_limit);
+	bq2415x_set_default_value(bq, weak_battery_voltage);
+	bq2415x_set_default_value(bq, battery_regulation_voltage);
+	if (bq->init_data.resistor_sense > 0) {
+		bq2415x_set_default_value(bq, charge_current);
+		bq2415x_set_default_value(bq, termination_current);
+		bq2415x_exec_command(bq, BQ2415X_CHARGE_TERMINATION_ENABLE);
+	}
+	bq2415x_exec_command(bq, BQ2415X_CHARGER_ENABLE);
+	return 0;
+}
+
+/**** charger mode functions ****/
+
+/* set charger mode */
+static int bq2415x_set_mode(struct bq2415x_device *bq, enum bq2415x_mode mode)
+{
+	int ret = 0;
+	int charger = 0;
+	int boost = 0;
+
+	if (mode == BQ2415X_MODE_HOST_CHARGER ||
+		mode == BQ2415X_MODE_DEDICATED_CHARGER)
+			charger = 1;
+
+	if (mode == BQ2415X_MODE_BOOST)
+		boost = 1;
+
+	if (!charger)
+		ret = bq2415x_exec_command(bq, BQ2415X_CHARGER_DISABLE);
+
+	if (!boost)
+		ret = bq2415x_exec_command(bq, BQ2415X_BOOST_MODE_DISABLE);
+
+	if (ret < 0)
+		return ret;
+
+	switch (mode) {
+	case BQ2415X_MODE_NONE:
+		dev_dbg(bq->dev, "changing mode to: N/A\n");
+		ret = bq2415x_set_current_limit(bq, 100);
+		break;
+	case BQ2415X_MODE_HOST_CHARGER:
+		dev_dbg(bq->dev, "changing mode to: Host/HUB charger\n");
+		ret = bq2415x_set_current_limit(bq, 500);
+		break;
+	case BQ2415X_MODE_DEDICATED_CHARGER:
+		dev_dbg(bq->dev, "changing mode to: Dedicated charger\n");
+		ret = bq2415x_set_current_limit(bq, 1800);
+		break;
+	case BQ2415X_MODE_BOOST: /* Boost mode */
+		dev_dbg(bq->dev, "changing mode to: Boost\n");
+		ret = bq2415x_set_current_limit(bq, 100);
+		break;
+	}
+
+	if (ret < 0)
+		return ret;
+
+	if (charger)
+		ret = bq2415x_exec_command(bq, BQ2415X_CHARGER_ENABLE);
+	else if (boost)
+		ret = bq2415x_exec_command(bq, BQ2415X_BOOST_MODE_ENABLE);
+
+	if (ret < 0)
+		return ret;
+
+	bq2415x_set_default_value(bq, weak_battery_voltage);
+	bq2415x_set_default_value(bq, battery_regulation_voltage);
+
+	bq->mode = mode;
+	sysfs_notify(&bq->charger.dev->kobj, NULL, "mode");
+
+	return 0;
+
+}
+
+/* hook function called by other driver which set reported mode */
+static void bq2415x_hook_function(enum bq2415x_mode mode, void *data)
+{
+	struct bq2415x_device *bq = data;
+
+	if (!bq)
+		return;
+
+	dev_dbg(bq->dev, "hook function was called\n");
+	bq->reported_mode = mode;
+
+	/* if automode is not enabled do not tell about reported_mode */
+	if (bq->automode < 1)
+		return;
+
+	sysfs_notify(&bq->charger.dev->kobj, NULL, "reported_mode");
+	bq2415x_set_mode(bq, bq->reported_mode);
+
+}
+
+/**** timer functions ****/
+
+/* enable/disable auto resetting chip timer */
+static void bq2415x_set_autotimer(struct bq2415x_device *bq, int state)
+{
+	mutex_lock(&bq2415x_timer_mutex);
+
+	if (bq->autotimer == state) {
+		mutex_unlock(&bq2415x_timer_mutex);
+		return;
+	}
+
+	bq->autotimer = state;
+
+	if (state) {
+		schedule_delayed_work(&bq->work, BQ2415X_TIMER_TIMEOUT * HZ);
+		bq2415x_exec_command(bq, BQ2415X_TIMER_RESET);
+		bq->timer_error = NULL;
+	} else {
+		cancel_delayed_work_sync(&bq->work);
+	}
+
+	mutex_unlock(&bq2415x_timer_mutex);
+}
+
+/* called by bq2415x_timer_work on timer error */
+static void bq2415x_timer_error(struct bq2415x_device *bq, const char *msg)
+{
+	bq->timer_error = msg;
+	sysfs_notify(&bq->charger.dev->kobj, NULL, "timer");
+	dev_err(bq->dev, "%s\n", msg);
+	if (bq->automode > 0)
+		bq->automode = 0;
+	bq2415x_set_mode(bq, BQ2415X_MODE_NONE);
+	bq2415x_set_autotimer(bq, 0);
+}
+
+/* delayed work function for auto resetting chip timer */
+static void bq2415x_timer_work(struct work_struct *work)
+{
+	struct bq2415x_device *bq = container_of(work, struct bq2415x_device,
+						work.work);
+	int ret, error, boost;
+
+	if (!bq->autotimer)
+		return;
+
+	ret = bq2415x_exec_command(bq, BQ2415X_TIMER_RESET);
+	if (ret < 0) {
+		bq2415x_timer_error(bq, "Resetting timer failed");
+		return;
+	}
+
+	boost = bq2415x_exec_command(bq, BQ2415X_BOOST_MODE_STATUS);
+	if (boost < 0) {
+		bq2415x_timer_error(bq, "Unknown error");
+		return;
+	}
+
+	error = bq2415x_exec_command(bq, BQ2415X_FAULT_STATUS);
+	if (error < 0) {
+		bq2415x_timer_error(bq, "Unknown error");
+		return;
+	}
+
+	if (boost) {
+		switch (error) {
+		/* Non fatal errors, chip is OK */
+		case 0: /* No error */
+			break;
+		case 6: /* Timer expired */
+			dev_err(bq->dev, "Timer expired\n");
+			break;
+		case 3: /* Battery voltage too low */
+			dev_err(bq->dev, "Battery voltage to low\n");
+			break;
+
+		/* Fatal errors, disable and reset chip */
+		case 1: /* Overvoltage protection (chip fried) */
+			bq2415x_timer_error(bq,
+				"Overvoltage protection (chip fried)");
+			return;
+		case 2: /* Overload */
+			bq2415x_timer_error(bq, "Overload");
+			return;
+		case 4: /* Battery overvoltage protection */
+			bq2415x_timer_error(bq,
+				"Battery overvoltage protection");
+			return;
+		case 5: /* Thermal shutdown (too hot) */
+			bq2415x_timer_error(bq,
+					"Thermal shutdown (too hot)");
+			return;
+		case 7: /* N/A */
+			bq2415x_timer_error(bq, "Unknown error");
+			return;
+		}
+	} else {
+		switch (error) {
+		/* Non fatal errors, chip is OK */
+		case 0: /* No error */
+			break;
+		case 2: /* Sleep mode */
+			dev_err(bq->dev, "Sleep mode\n");
+			break;
+		case 3: /* Poor input source */
+			dev_err(bq->dev, "Poor input source\n");
+			break;
+		case 6: /* Timer expired */
+			dev_err(bq->dev, "Timer expired\n");
+			break;
+		case 7: /* No battery */
+			dev_err(bq->dev, "No battery\n");
+			break;
+
+		/* Fatal errors, disable and reset chip */
+		case 1: /* Overvoltage protection (chip fried) */
+			bq2415x_timer_error(bq,
+				"Overvoltage protection (chip fried)");
+			return;
+		case 4: /* Battery overvoltage protection */
+			bq2415x_timer_error(bq,
+				"Battery overvoltage protection");
+			return;
+		case 5: /* Thermal shutdown (too hot) */
+			bq2415x_timer_error(bq,
+				"Thermal shutdown (too hot)");
+			return;
+		}
+	}
+
+	schedule_delayed_work(&bq->work, BQ2415X_TIMER_TIMEOUT * HZ);
+}
+
+/**** power supply interface code ****/
+
+static enum power_supply_property bq2415x_power_supply_props[] = {
+	/* TODO: maybe add more power supply properties */
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_MODEL_NAME,
+};
+
+static int bq2415x_power_supply_get_property(struct power_supply *psy,
+	enum power_supply_property psp, union power_supply_propval *val)
+{
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+	int ret;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_STATUS:
+		ret = bq2415x_exec_command(bq, BQ2415X_CHARGE_STATUS);
+		if (ret < 0)
+			return ret;
+		else if (ret == 0) /* Ready */
+			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+		else if (ret == 1) /* Charge in progress */
+			val->intval = POWER_SUPPLY_STATUS_CHARGING;
+		else if (ret == 2) /* Charge done */
+			val->intval = POWER_SUPPLY_STATUS_FULL;
+		else
+			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
+		break;
+	case POWER_SUPPLY_PROP_MODEL_NAME:
+		val->strval = bq->model;
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int bq2415x_power_supply_init(struct bq2415x_device *bq)
+{
+	int ret;
+	int chip;
+	char revstr[8];
+
+	bq->charger.name = bq->name;
+	bq->charger.type = POWER_SUPPLY_TYPE_USB;
+	bq->charger.properties = bq2415x_power_supply_props;
+	bq->charger.num_properties = ARRAY_SIZE(bq2415x_power_supply_props);
+	bq->charger.get_property = bq2415x_power_supply_get_property;
+
+	ret = bq2415x_detect_chip(bq);
+	if (ret < 0)
+		chip = BQUNKNOWN;
+	else
+		chip = ret;
+
+	ret = bq2415x_detect_revision(bq);
+	if (ret < 0)
+		strcpy(revstr, "unknown");
+	else
+		sprintf(revstr, "1.%d", ret);
+
+	bq->model = kasprintf(GFP_KERNEL,
+				"chip %s, revision %s, vender code %.3d",
+				bq2415x_chip_name[chip], revstr,
+				bq2415x_get_vender_code(bq));
+	if (!bq->model) {
+		dev_err(bq->dev, "failed to allocate model name\n");
+		return -ENOMEM;
+	}
+
+	ret = power_supply_register(bq->dev, &bq->charger);
+	if (ret) {
+		kfree(bq->model);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void bq2415x_power_supply_exit(struct bq2415x_device *bq)
+{
+	bq->autotimer = 0;
+	if (bq->automode > 0)
+		bq->automode = 0;
+	cancel_delayed_work_sync(&bq->work);
+	power_supply_unregister(&bq->charger);
+	kfree(bq->model);
+}
+
+/**** additional sysfs entries for power supply interface ****/
+
+/* show *_status entries */
+static ssize_t bq2415x_sysfs_show_status(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+	enum bq2415x_command command;
+	int ret;
+
+	if (strcmp(attr->attr.name, "otg_status") == 0)
+		command = BQ2415X_OTG_STATUS;
+	else if (strcmp(attr->attr.name, "charge_status") == 0)
+		command = BQ2415X_CHARGE_STATUS;
+	else if (strcmp(attr->attr.name, "boost_status") == 0)
+		command = BQ2415X_BOOST_STATUS;
+	else if (strcmp(attr->attr.name, "fault_status") == 0)
+		command = BQ2415X_FAULT_STATUS;
+	else
+		return -EINVAL;
+
+	ret = bq2415x_exec_command(bq, command);
+	if (ret < 0)
+		return ret;
+	else
+		return sprintf(buf, "%d\n", ret);
+}
+
+/* set timer entry:
+     auto - enable auto mode
+     off - disable auto mode
+     (other values) - reset chip timer
+*/
+static ssize_t bq2415x_sysfs_set_timer(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+	int ret = 0;
+
+	if (strncmp(buf, "auto", 4) == 0)
+		bq2415x_set_autotimer(bq, 1);
+	else if (strncmp(buf, "off", 3) == 0)
+		bq2415x_set_autotimer(bq, 0);
+	else
+		ret = bq2415x_exec_command(bq, BQ2415X_TIMER_RESET);
+
+	if (ret < 0)
+		return ret;
+	else
+		return count;
+}
+
+/* show timer entry (auto or off) */
+static ssize_t bq2415x_sysfs_show_timer(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+
+	if (bq->timer_error)
+		return sprintf(buf, "%s\n", bq->timer_error);
+
+	if (bq->autotimer)
+		return sprintf(buf, "auto\n");
+	else
+		return sprintf(buf, "off\n");
+}
+
+/* set mode entry:
+     auto - if automode is supported, enable it and set mode to reported
+     none - disable charger and boost mode
+     host - charging mode for host/hub chargers (current limit 500mA)
+     dedicated - charging mode for dedicated chargers (unlimited current limit)
+     boost - disable charger and enable boost mode
+*/
+static ssize_t bq2415x_sysfs_set_mode(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+	enum bq2415x_mode mode;
+	int ret = 0;
+
+	if (strncmp(buf, "auto", 4) == 0) {
+		if (bq->automode < 0)
+			return -ENOSYS;
+		bq->automode = 1;
+		mode = bq->reported_mode;
+	} else if (strncmp(buf, "none", 4) == 0) {
+		if (bq->automode > 0)
+			bq->automode = 0;
+		mode = BQ2415X_MODE_NONE;
+	} else if (strncmp(buf, "host", 4) == 0) {
+		if (bq->automode > 0)
+			bq->automode = 0;
+		mode = BQ2415X_MODE_HOST_CHARGER;
+	} else if (strncmp(buf, "dedicated", 9) == 0) {
+		if (bq->automode > 0)
+			bq->automode = 0;
+		mode = BQ2415X_MODE_DEDICATED_CHARGER;
+	} else if (strncmp(buf, "boost", 5) == 0) {
+		if (bq->automode > 0)
+			bq->automode = 0;
+		mode = BQ2415X_MODE_BOOST;
+	} else if (strncmp(buf, "reset", 5) == 0) {
+		bq2415x_reset_chip(bq);
+		bq2415x_set_defaults(bq);
+		if (bq->automode <= 0)
+			return count;
+		bq->automode = 1;
+		mode = bq->reported_mode;
+	} else
+		return -EINVAL;
+
+	ret = bq2415x_set_mode(bq, mode);
+	if (ret < 0)
+		return ret;
+	else
+		return count;
+}
+
+/* show mode entry (auto, none, host, dedicated or boost) */
+static ssize_t bq2415x_sysfs_show_mode(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+	ssize_t ret = 0;
+
+	if (bq->automode > 0)
+		ret += sprintf(buf+ret, "auto (");
+
+	switch (bq->mode) {
+	case BQ2415X_MODE_NONE:
+		ret += sprintf(buf+ret, "none");
+		break;
+	case BQ2415X_MODE_HOST_CHARGER:
+		ret += sprintf(buf+ret, "host");
+		break;
+	case BQ2415X_MODE_DEDICATED_CHARGER:
+		ret += sprintf(buf+ret, "dedicated");
+		break;
+	case BQ2415X_MODE_BOOST:
+		ret += sprintf(buf+ret, "boost");
+		break;
+	}
+
+	if (bq->automode > 0)
+		ret += sprintf(buf+ret, ")");
+
+	ret += sprintf(buf+ret, "\n");
+	return ret;
+}
+
+/* show reported_mode entry (none, host, dedicated or boost) */
+static ssize_t bq2415x_sysfs_show_reported_mode(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+
+	if (bq->automode < 0)
+		return -EINVAL;
+
+	switch (bq->reported_mode) {
+	case BQ2415X_MODE_NONE:
+		return sprintf(buf, "none\n");
+	case BQ2415X_MODE_HOST_CHARGER:
+		return sprintf(buf, "host\n");
+	case BQ2415X_MODE_DEDICATED_CHARGER:
+		return sprintf(buf, "dedicated\n");
+	case BQ2415X_MODE_BOOST:
+		return sprintf(buf, "boost\n");
+	}
+
+	return -EINVAL;
+}
+
+/* directly set raw value to chip register, format: 'register value' */
+static ssize_t bq2415x_sysfs_set_registers(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+	ssize_t ret = 0;
+	unsigned int reg;
+	unsigned int val;
+
+	if (sscanf(buf, "%x %x", &reg, &val) != 2)
+		return -EINVAL;
+
+	if (reg > 4 || val > 255)
+		return -EINVAL;
+
+	ret = bq2415x_i2c_write(bq, reg, val);
+	if (ret < 0)
+		return ret;
+	else
+		return count;
+}
+
+/* print value of chip register, format: 'register=value' */
+static ssize_t bq2415x_sysfs_print_reg(struct bq2415x_device *bq,
+					u8 reg, char *buf)
+{
+	int ret = bq2415x_i2c_read(bq, reg);
+	if (ret < 0)
+		return sprintf(buf, "%#.2x=error %d\n", reg, ret);
+	else
+		return sprintf(buf, "%#.2x=%#.2x\n", reg, ret);
+}
+
+/* show all raw values of chip register, format per line: 'register=value' */
+static ssize_t bq2415x_sysfs_show_registers(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+	ssize_t ret = 0;
+
+	ret += bq2415x_sysfs_print_reg(bq, BQ2415X_REG_STATUS, buf+ret);
+	ret += bq2415x_sysfs_print_reg(bq, BQ2415X_REG_CONTROL, buf+ret);
+	ret += bq2415x_sysfs_print_reg(bq, BQ2415X_REG_VOLTAGE, buf+ret);
+	ret += bq2415x_sysfs_print_reg(bq, BQ2415X_REG_VENDER, buf+ret);
+	ret += bq2415x_sysfs_print_reg(bq, BQ2415X_REG_CURRENT, buf+ret);
+	return ret;
+}
+
+/* set current and voltage limit entries (in mA or mV) */
+static ssize_t bq2415x_sysfs_set_limit(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+	long val;
+	int ret;
+
+	if (kstrtol(buf, 10, &val) < 0)
+		return -EINVAL;
+
+	if (strcmp(attr->attr.name, "current_limit") == 0)
+		ret = bq2415x_set_current_limit(bq, val);
+	else if (strcmp(attr->attr.name, "weak_battery_voltage") == 0)
+		ret = bq2415x_set_weak_battery_voltage(bq, val);
+	else if (strcmp(attr->attr.name, "battery_regulation_voltage") == 0)
+		ret = bq2415x_set_battery_regulation_voltage(bq, val);
+	else if (strcmp(attr->attr.name, "charge_current") == 0)
+		ret = bq2415x_set_charge_current(bq, val);
+	else if (strcmp(attr->attr.name, "termination_current") == 0)
+		ret = bq2415x_set_termination_current(bq, val);
+	else
+		return -EINVAL;
+
+	if (ret < 0)
+		return ret;
+	else
+		return count;
+}
+
+/* show current and voltage limit entries (in mA or mV) */
+static ssize_t bq2415x_sysfs_show_limit(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+	int ret;
+
+	if (strcmp(attr->attr.name, "current_limit") == 0)
+		ret = bq2415x_get_current_limit(bq);
+	else if (strcmp(attr->attr.name, "weak_battery_voltage") == 0)
+		ret = bq2415x_get_weak_battery_voltage(bq);
+	else if (strcmp(attr->attr.name, "battery_regulation_voltage") == 0)
+		ret = bq2415x_get_battery_regulation_voltage(bq);
+	else if (strcmp(attr->attr.name, "charge_current") == 0)
+		ret = bq2415x_get_charge_current(bq);
+	else if (strcmp(attr->attr.name, "termination_current") == 0)
+		ret = bq2415x_get_termination_current(bq);
+	else
+		return -EINVAL;
+
+	if (ret < 0)
+		return ret;
+	else
+		return sprintf(buf, "%d\n", ret);
+}
+
+/* set *_enable entries */
+static ssize_t bq2415x_sysfs_set_enable(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+	enum bq2415x_command command;
+	long val;
+	int ret;
+
+	if (kstrtol(buf, 10, &val) < 0)
+		return -EINVAL;
+
+	if (strcmp(attr->attr.name, "charge_termination_enable") == 0)
+		command = val ? BQ2415X_CHARGE_TERMINATION_ENABLE :
+			BQ2415X_CHARGE_TERMINATION_DISABLE;
+	else if (strcmp(attr->attr.name, "high_impedance_enable") == 0)
+		command = val ? BQ2415X_HIGH_IMPEDANCE_ENABLE :
+			BQ2415X_HIGH_IMPEDANCE_DISABLE;
+	else if (strcmp(attr->attr.name, "otg_pin_enable") == 0)
+		command = val ? BQ2415X_OTG_PIN_ENABLE :
+			BQ2415X_OTG_PIN_DISABLE;
+	else if (strcmp(attr->attr.name, "stat_pin_enable") == 0)
+		command = val ? BQ2415X_STAT_PIN_ENABLE :
+			BQ2415X_STAT_PIN_DISABLE;
+	else
+		return -EINVAL;
+
+	ret = bq2415x_exec_command(bq, command);
+	if (ret < 0)
+		return ret;
+	else
+		return count;
+}
+
+/* show *_enable entries */
+static ssize_t bq2415x_sysfs_show_enable(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct power_supply *psy = dev_get_drvdata(dev);
+	struct bq2415x_device *bq = container_of(psy, struct bq2415x_device,
+						charger);
+	enum bq2415x_command command;
+	int ret;
+
+	if (strcmp(attr->attr.name, "charge_termination_enable") == 0)
+		command = BQ2415X_CHARGE_TERMINATION_STATUS;
+	else if (strcmp(attr->attr.name, "high_impedance_enable") == 0)
+		command = BQ2415X_HIGH_IMPEDANCE_STATUS;
+	else if (strcmp(attr->attr.name, "otg_pin_enable") == 0)
+		command = BQ2415X_OTG_PIN_STATUS;
+	else if (strcmp(attr->attr.name, "stat_pin_enable") == 0)
+		command = BQ2415X_STAT_PIN_STATUS;
+	else
+		return -EINVAL;
+
+	ret = bq2415x_exec_command(bq, command);
+	if (ret < 0)
+		return ret;
+	else
+		return sprintf(buf, "%d\n", ret);
+}
+
+static DEVICE_ATTR(current_limit, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_limit, bq2415x_sysfs_set_limit);
+static DEVICE_ATTR(weak_battery_voltage, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_limit, bq2415x_sysfs_set_limit);
+static DEVICE_ATTR(battery_regulation_voltage, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_limit, bq2415x_sysfs_set_limit);
+static DEVICE_ATTR(charge_current, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_limit, bq2415x_sysfs_set_limit);
+static DEVICE_ATTR(termination_current, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_limit, bq2415x_sysfs_set_limit);
+
+static DEVICE_ATTR(charge_termination_enable, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_enable, bq2415x_sysfs_set_enable);
+static DEVICE_ATTR(high_impedance_enable, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_enable, bq2415x_sysfs_set_enable);
+static DEVICE_ATTR(otg_pin_enable, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_enable, bq2415x_sysfs_set_enable);
+static DEVICE_ATTR(stat_pin_enable, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_enable, bq2415x_sysfs_set_enable);
+
+static DEVICE_ATTR(reported_mode, S_IRUGO,
+		bq2415x_sysfs_show_reported_mode, NULL);
+static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_mode, bq2415x_sysfs_set_mode);
+static DEVICE_ATTR(timer, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_timer, bq2415x_sysfs_set_timer);
+
+static DEVICE_ATTR(registers, S_IWUSR | S_IRUGO,
+		bq2415x_sysfs_show_registers, bq2415x_sysfs_set_registers);
+
+static DEVICE_ATTR(otg_status, S_IRUGO, bq2415x_sysfs_show_status, NULL);
+static DEVICE_ATTR(charge_status, S_IRUGO, bq2415x_sysfs_show_status, NULL);
+static DEVICE_ATTR(boost_status, S_IRUGO, bq2415x_sysfs_show_status, NULL);
+static DEVICE_ATTR(fault_status, S_IRUGO, bq2415x_sysfs_show_status, NULL);
+
+static struct attribute *bq2415x_sysfs_attributes[] = {
+	&dev_attr_current_limit.attr,
+	&dev_attr_weak_battery_voltage.attr,
+	&dev_attr_battery_regulation_voltage.attr,
+	&dev_attr_charge_current.attr,
+	&dev_attr_termination_current.attr,
+
+	&dev_attr_charge_termination_enable.attr,
+	&dev_attr_high_impedance_enable.attr,
+	&dev_attr_otg_pin_enable.attr,
+	&dev_attr_stat_pin_enable.attr,
+
+	&dev_attr_reported_mode.attr,
+	&dev_attr_mode.attr,
+	&dev_attr_timer.attr,
+
+	&dev_attr_registers.attr,
+
+	&dev_attr_otg_status.attr,
+	&dev_attr_charge_status.attr,
+	&dev_attr_boost_status.attr,
+	&dev_attr_fault_status.attr,
+	NULL,
+};
+
+static const struct attribute_group bq2415x_sysfs_attr_group = {
+	.attrs = bq2415x_sysfs_attributes,
+};
+
+static int bq2415x_sysfs_init(struct bq2415x_device *bq)
+{
+	return sysfs_create_group(&bq->charger.dev->kobj,
+			&bq2415x_sysfs_attr_group);
+}
+
+static void bq2415x_sysfs_exit(struct bq2415x_device *bq)
+{
+	sysfs_remove_group(&bq->charger.dev->kobj, &bq2415x_sysfs_attr_group);
+}
+
+/* main bq2415x probe function */
+static int bq2415x_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
+{
+	int ret;
+	int num;
+	char *name;
+	struct bq2415x_device *bq;
+
+	if (!client->dev.platform_data) {
+		dev_err(&client->dev, "platform data not set\n");
+		return -ENODEV;
+	}
+
+	/* Get new ID for the new device */
+	ret = idr_pre_get(&bq2415x_id, GFP_KERNEL);
+	if (ret == 0)
+		return -ENOMEM;
+
+	mutex_lock(&bq2415x_id_mutex);
+	ret = idr_get_new(&bq2415x_id, client, &num);
+	mutex_unlock(&bq2415x_id_mutex);
+
+	if (ret < 0)
+		return ret;
+
+	name = kasprintf(GFP_KERNEL, "%s-%d", id->name, num);
+	if (!name) {
+		dev_err(&client->dev, "failed to allocate device name\n");
+		ret = -ENOMEM;
+		goto error_1;
+	}
+
+	bq = kzalloc(sizeof(*bq), GFP_KERNEL);
+	if (!bq) {
+		dev_err(&client->dev, "failed to allocate device data\n");
+		ret = -ENOMEM;
+		goto error_2;
+	}
+
+	i2c_set_clientdata(client, bq);
+
+	bq->id = num;
+	bq->dev = &client->dev;
+	bq->chip = id->driver_data;
+	bq->name = name;
+	bq->mode = BQ2415X_MODE_NONE;
+	bq->reported_mode = BQ2415X_MODE_NONE;
+	bq->autotimer = 0;
+	bq->automode = 0;
+
+	memcpy(&bq->init_data, client->dev.platform_data,
+			sizeof(bq->init_data));
+
+	bq2415x_reset_chip(bq);
+
+	ret = bq2415x_power_supply_init(bq);
+	if (ret) {
+		dev_err(bq->dev, "failed to register power supply: %d\n", ret);
+		goto error_3;
+	}
+
+	ret = bq2415x_sysfs_init(bq);
+	if (ret) {
+		dev_err(bq->dev, "failed to create sysfs entries: %d\n", ret);
+		goto error_4;
+	}
+
+	ret = bq2415x_set_defaults(bq);
+	if (ret) {
+		dev_err(bq->dev, "failed to set default values: %d\n", ret);
+		goto error_5;
+	}
+
+	if (bq->init_data.set_mode_hook) {
+		if (bq->init_data.set_mode_hook(
+				bq2415x_hook_function, bq)) {
+			bq->automode = 1;
+			bq2415x_set_mode(bq, bq->reported_mode);
+			dev_info(bq->dev, "automode enabled\n");
+		} else {
+			bq->automode = -1;
+			dev_info(bq->dev, "automode failed\n");
+		}
+	} else {
+		bq->automode = -1;
+		dev_info(bq->dev, "automode not supported\n");
+	}
+
+	INIT_DELAYED_WORK(&bq->work, bq2415x_timer_work);
+	bq2415x_set_autotimer(bq, 1);
+
+	dev_info(bq->dev, "driver registered\n");
+	return 0;
+
+error_5:
+	bq2415x_sysfs_exit(bq);
+error_4:
+	bq2415x_power_supply_exit(bq);
+error_3:
+	kfree(bq);
+error_2:
+	kfree(name);
+error_1:
+	mutex_lock(&bq2415x_id_mutex);
+	idr_remove(&bq2415x_id, num);
+	mutex_unlock(&bq2415x_id_mutex);
+
+	return ret;
+}
+
+/* main bq2415x remove function */
+
+static int bq2415x_remove(struct i2c_client *client)
+{
+	struct bq2415x_device *bq = i2c_get_clientdata(client);
+
+	if (bq->init_data.set_mode_hook)
+		bq->init_data.set_mode_hook(NULL, NULL);
+
+	bq2415x_sysfs_exit(bq);
+	bq2415x_power_supply_exit(bq);
+
+	bq2415x_reset_chip(bq);
+
+	mutex_lock(&bq2415x_id_mutex);
+	idr_remove(&bq2415x_id, bq->id);
+	mutex_unlock(&bq2415x_id_mutex);
+
+	dev_info(bq->dev, "driver unregistered\n");
+
+	kfree(bq->name);
+	kfree(bq);
+
+	return 0;
+}
+
+static const struct i2c_device_id bq2415x_i2c_id_table[] = {
+	{ "bq2415x", BQUNKNOWN },
+	{ "bq24150", BQ24150 },
+	{ "bq24150a", BQ24150A },
+	{ "bq24151", BQ24151 },
+	{ "bq24151a", BQ24151A },
+	{ "bq24152", BQ24152 },
+	{ "bq24153", BQ24153 },
+	{ "bq24153a", BQ24153A },
+	{ "bq24155", BQ24155 },
+	{ "bq24156", BQ24156 },
+	{ "bq24156a", BQ24156A },
+	{ "bq24158", BQ24158 },
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, bq2415x_i2c_id_table);
+
+static struct i2c_driver bq2415x_driver = {
+	.driver = {
+		.name = "bq2415x-charger",
+	},
+	.probe = bq2415x_probe,
+	.remove = bq2415x_remove,
+	.id_table = bq2415x_i2c_id_table,
+};
+
+static int __init bq2415x_init(void)
+{
+	return i2c_add_driver(&bq2415x_driver);
+}
+module_init(bq2415x_init);
+
+static void __exit bq2415x_exit(void)
+{
+	i2c_del_driver(&bq2415x_driver);
+}
+module_exit(bq2415x_exit);
+
+MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
+MODULE_DESCRIPTION("bq2415x charger driver");
+MODULE_LICENSE("GPL");