power: ab5500-fg: fuel gauge driver for ab5500

This is a low level ab5500 fuel gauge driver. A power supply class of
type fg is registered to display the battery parameters such as energy,
charge, capacity, voltage.

ST-Ericsson Linux next: Not Tested
ST-Ericsson ID: WP332221
ST-Ericsson FOSS-OUT ID: Trivial

Change-Id: Ibe508dd84836a9a4873539ce194b50788ea25cba
Signed-off-by: Arun Murthy <arun.murthy@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/23151
Reviewed-by: QATEST
Reviewed-by: Johan PALSSON <johan.palsson@stericsson.com>
Reviewed-by: Srinidhi KASAGAR <srinidhi.kasagar@stericsson.com>

1 files changed, 1830 insertions, 0 deletions

diff --git a/drivers/power/ab5500_fg.c b/drivers/power/ab5500_fg.c
new file mode 100644
index 00000000000..1c866e8fec5
--- /dev/null
+++ b/drivers/power/ab5500_fg.c
@@ -0,0 +1,1830 @@
+/*
+ * Copyright (C) ST-Ericsson AB 2011
+ *
+ * Main and Back-up battery management driver.
+ *
+ * Note: Backup battery management is required in case of Li-Ion battery and not
+ * for capacitive battery. HREF boards have capacitive battery and hence backup
+ * battery management is not used and the supported code is available in this
+ * driver.
+ *
+ * License Terms: GNU General Public License v2
+ * Authors:
+ *	Johan Palsson <johan.palsson@stericsson.com>
+ *	Karl Komierowski <karl.komierowski@stericsson.com>
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+#include <linux/delay.h>
+#include <linux/mfd/abx500/ab5500-gpadc.h>
+#include <linux/mfd/abx500/ab5500-bm.h>
+#include <linux/mfd/abx500/ab5500.h>
+#include <linux/mfd/abx500.h>
+
+static LIST_HEAD(ab5500_fg_list);
+
+/* U5500 Constants */
+#define FG_ON_MASK			0x04
+#define FG_ON				0x04
+#define FG_ACC_RESET_ON_READ_MASK	0x08
+#define FG_ACC_RESET_ON_READ		0x08
+#define EN_READOUT_MASK			0x01
+#define EN_READOUT			0x01
+#define RESET				0x00
+#define EOC_52_mA			0x04
+#define MILLI_TO_MICRO			1000
+#define FG_LSB_IN_MA			770
+#define QLSB_NANO_AMP_HOURS_X10		1129
+#define SEC_TO_SAMPLE(S)		(S * 4)
+#define NBR_AVG_SAMPLES			20
+#define LOW_BAT_CHECK_INTERVAL		(2 * HZ)
+
+#define VALID_CAPACITY_SEC		(45 * 60) /* 45 minutes */
+
+#define interpolate(x, x1, y1, x2, y2) \
+	((y1) + ((((y2) - (y1)) * ((x) - (x1))) / ((x2) - (x1))));
+
+#define to_ab5500_fg_device_info(x) container_of((x), \
+	struct ab5500_fg, fg_psy);
+
+/**
+ * struct ab5500_fg_interrupts - ab5500 fg interupts
+ * @name:	name of the interrupt
+ * @isr		function pointer to the isr
+ */
+struct ab5500_fg_interrupts {
+	char *name;
+	irqreturn_t (*isr)(int irq, void *data);
+};
+
+enum ab5500_fg_discharge_state {
+	AB5500_FG_DISCHARGE_INIT,
+	AB5500_FG_DISCHARGE_INITMEASURING,
+	AB5500_FG_DISCHARGE_INIT_RECOVERY,
+	AB5500_FG_DISCHARGE_RECOVERY,
+	AB5500_FG_DISCHARGE_READOUT,
+	AB5500_FG_DISCHARGE_WAKEUP,
+};
+
+static char *discharge_state[] = {
+	"DISCHARGE_INIT",
+	"DISCHARGE_INITMEASURING",
+	"DISCHARGE_INIT_RECOVERY",
+	"DISCHARGE_RECOVERY",
+	"DISCHARGE_READOUT",
+	"DISCHARGE_WAKEUP",
+};
+
+enum ab5500_fg_charge_state {
+	AB5500_FG_CHARGE_INIT,
+	AB5500_FG_CHARGE_READOUT,
+};
+
+static char *charge_state[] = {
+	"CHARGE_INIT",
+	"CHARGE_READOUT",
+};
+
+enum ab5500_fg_calibration_state {
+	AB5500_FG_CALIB_INIT,
+	AB5500_FG_CALIB_WAIT,
+	AB5500_FG_CALIB_END,
+};
+
+struct ab5500_fg_avg_cap {
+	int avg;
+	int samples[NBR_AVG_SAMPLES];
+	__kernel_time_t time_stamps[NBR_AVG_SAMPLES];
+	int pos;
+	int nbr_samples;
+	int sum;
+};
+
+struct ab5500_fg_battery_capacity {
+	int max_mah_design;
+	int max_mah;
+	int mah;
+	int permille;
+	int level;
+	int prev_mah;
+	int prev_percent;
+	int prev_level;
+};
+
+struct ab5500_fg_flags {
+	bool fg_enabled;
+	bool conv_done;
+	bool charging;
+	bool fully_charged;
+	bool low_bat_delay;
+	bool low_bat;
+	bool bat_ovv;
+	bool batt_unknown;
+	bool calibrate;
+};
+
+/**
+ * struct ab5500_fg - ab5500 FG device information
+ * @dev:		Pointer to the structure device
+ * @vbat:		Battery voltage in mV
+ * @vbat_nom:		Nominal battery voltage in mV
+ * @inst_curr:		Instantenous battery current in mA
+ * @avg_curr:		Average battery current in mA
+ * @fg_samples:		Number of samples used in the FG accumulation
+ * @accu_charge:	Accumulated charge from the last conversion
+ * @recovery_cnt:	Counter for recovery mode
+ * @high_curr_cnt:	Counter for high current mode
+ * @init_cnt:		Counter for init mode
+ * @v_to_cap:		capacity based on battery voltage
+ * @recovery_needed:	Indicate if recovery is needed
+ * @high_curr_mode:	Indicate if we're in high current mode
+ * @init_capacity:	Indicate if initial capacity measuring should be done
+ * @calib_state		State during offset calibration
+ * @discharge_state:	Current discharge state
+ * @charge_state:	Current charge state
+ * @flags:		Structure for information about events triggered
+ * @bat_cap:		Structure for battery capacity specific parameters
+ * @avg_cap:		Average capacity filter
+ * @parent:		Pointer to the struct ab5500
+ * @gpadc:		Pointer to the struct gpadc
+ * @gpadc_auto:		Pointer tot he struct adc_auto_input
+ * @pdata:		Pointer to the ab5500_fg platform data
+ * @bat:		Pointer to the ab5500_bm platform data
+ * @fg_psy:		Structure that holds the FG specific battery properties
+ * @fg_wq:		Work queue for running the FG algorithm
+ * @fg_periodic_work:	Work to run the FG algorithm periodically
+ * @fg_low_bat_work:	Work to check low bat condition
+ * @fg_work:		Work to run the FG algorithm instantly
+ * @fg_acc_cur_work:	Work to read the FG accumulator
+ * @cc_lock:		Mutex for locking the CC
+ * @node:		struct of type list_head
+ */
+struct ab5500_fg {
+	struct device *dev;
+	int vbat;
+	int vbat_nom;
+	int inst_curr;
+	int avg_curr;
+	int fg_samples;
+	int accu_charge;
+	int recovery_cnt;
+	int high_curr_cnt;
+	int init_cnt;
+	int v_to_cap;
+	bool recovery_needed;
+	bool high_curr_mode;
+	bool init_capacity;
+	enum ab5500_fg_calibration_state calib_state;
+	enum ab5500_fg_discharge_state discharge_state;
+	enum ab5500_fg_charge_state charge_state;
+	struct ab5500_fg_flags flags;
+	struct ab5500_fg_battery_capacity bat_cap;
+	struct ab5500_fg_avg_cap avg_cap;
+	struct ab5500 *parent;
+	struct ab5500_gpadc *gpadc;
+	struct adc_auto_input *gpadc_auto;
+	struct abx500_fg_platform_data *pdata;
+	struct abx500_bm_data *bat;
+	struct power_supply fg_psy;
+	struct workqueue_struct *fg_wq;
+	struct delayed_work fg_periodic_work;
+	struct delayed_work fg_low_bat_work;
+	struct work_struct fg_work;
+	struct delayed_work fg_acc_cur_work;
+	struct mutex cc_lock;
+	struct list_head node;
+	struct timer_list avg_current_timer;
+};
+
+/* Main battery properties */
+static enum power_supply_property ab5500_fg_props[] = {
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CURRENT_AVG,
+	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
+	POWER_SUPPLY_PROP_ENERGY_FULL,
+	POWER_SUPPLY_PROP_ENERGY_NOW,
+	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+};
+
+struct ab5500_fg *ab5500_fg_get(void)
+{
+	struct ab5500_fg *di;
+	di = list_first_entry(&ab5500_fg_list, struct ab5500_fg, node);
+
+	return di;
+}
+
+/**
+ * ab5500_fg_is_low_curr() - Low or high current mode
+ * @di:		pointer to the ab5500_fg structure
+ * @curr:	the current to base or our decision on
+ *
+ * Low current mode if the current consumption is below a certain threshold
+ */
+static int ab5500_fg_is_low_curr(struct ab5500_fg *di, int curr)
+{
+	/*
+	 * We want to know if we're in low current mode
+	 */
+	if (curr > -di->bat->fg_params->high_curr_threshold)
+		return true;
+	else
+		return false;
+}
+
+/**
+ * ab5500_fg_add_cap_sample() - Add capacity to average filter
+ * @di:		pointer to the ab5500_fg structure
+ * @sample:	the capacity in mAh to add to the filter
+ *
+ * A capacity is added to the filter and a new mean capacity is calculated and
+ * returned
+ */
+static int ab5500_fg_add_cap_sample(struct ab5500_fg *di, int sample)
+{
+	struct timespec ts;
+	struct ab5500_fg_avg_cap *avg = &di->avg_cap;
+
+	getnstimeofday(&ts);
+
+	do {
+		avg->sum += sample - avg->samples[avg->pos];
+		avg->samples[avg->pos] = sample;
+		avg->time_stamps[avg->pos] = ts.tv_sec;
+		avg->pos++;
+
+		if (avg->pos == NBR_AVG_SAMPLES)
+			avg->pos = 0;
+
+		if (avg->nbr_samples < NBR_AVG_SAMPLES)
+			avg->nbr_samples++;
+
+		/*
+		 * Check the time stamp for each sample. If too old,
+		 * replace with latest sample
+		 */
+	} while (ts.tv_sec - VALID_CAPACITY_SEC > avg->time_stamps[avg->pos]);
+
+	avg->avg = avg->sum / avg->nbr_samples;
+
+	return avg->avg;
+}
+
+/**
+ * ab5500_fg_fill_cap_sample() - Fill average filter
+ * @di:		pointer to the ab5500_fg structure
+ * @sample:	the capacity in mAh to fill the filter with
+ *
+ * The capacity filter is filled with a capacity in mAh
+ */
+static void ab5500_fg_fill_cap_sample(struct ab5500_fg *di, int sample)
+{
+	int i;
+	struct timespec ts;
+	struct ab5500_fg_avg_cap *avg = &di->avg_cap;
+
+	getnstimeofday(&ts);
+
+	for (i = 0; i < NBR_AVG_SAMPLES; i++) {
+		avg->samples[i] = sample;
+		avg->time_stamps[i] = ts.tv_sec;
+	}
+
+	avg->pos = 0;
+	avg->nbr_samples = NBR_AVG_SAMPLES;
+	avg->sum = sample * NBR_AVG_SAMPLES;
+	avg->avg = sample;
+}
+
+/**
+ * ab5500_fg_coulomb_counter() - enable coulomb counter
+ * @di:		pointer to the ab5500_fg structure
+ * @enable:	enable/disable
+ *
+ * Enable/Disable coulomb counter.
+ * On failure returns negative value.
+ */
+static int ab5500_fg_coulomb_counter(struct ab5500_fg *di, bool enable)
+{
+	int ret = 0;
+	mutex_lock(&di->cc_lock);
+	if (enable) {
+		/* Power-up the CC */
+		ret = abx500_set_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC, AB5500_FG_CONTROL_A,
+			(FG_ON | FG_ACC_RESET_ON_READ));
+		if (ret)
+			goto cc_err;
+
+		di->flags.fg_enabled = true;
+	} else {
+		/* Stop the CC */
+		ret = abx500_mask_and_set_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC, AB5500_FG_CONTROL_A,
+			FG_ON_MASK, RESET);
+		if (ret)
+			goto cc_err;
+
+		di->flags.fg_enabled = false;
+
+	}
+	dev_dbg(di->dev, " CC enabled: %d Samples: %d\n",
+		enable, di->fg_samples);
+
+	mutex_unlock(&di->cc_lock);
+
+	return ret;
+cc_err:
+	dev_err(di->dev, "%s Enabling coulomb counter failed\n", __func__);
+	mutex_unlock(&di->cc_lock);
+	return ret;
+}
+
+/**
+ * ab5500_fg_inst_curr() - battery instantaneous current
+ * @di:         pointer to the ab5500_fg structure
+ *
+ * Returns battery instantenous current(on success) else error code
+ */
+static int ab5500_fg_inst_curr(struct ab5500_fg *di)
+{
+	u8 low, high, value;
+	static int val;
+	int ret = 0;
+	bool fg_off = false;
+
+	if (!di->flags.fg_enabled) {
+		fg_off = true;
+		/* Power-up the CC */
+		ab5500_fg_coulomb_counter(di, true);
+		msleep(250);
+	}
+
+	mutex_lock(&di->cc_lock);
+	/*
+	 * Since there is no interrupt for this, just wait for 250ms
+	 * 250ms is one sample conversion time with 32.768 Khz RTC clock
+	 */
+	msleep(250);
+
+	/* Enable read request */
+	ret = abx500_mask_and_set_register_interruptible(di->dev,
+		AB5500_BANK_FG_BATTCOM_ACC, AB5500_FG_CONTROL_B,
+		EN_READOUT_MASK, EN_READOUT);
+	if (ret)
+		goto inst_curr_err;
+
+	/* Read CC Sample conversion value Low and high */
+	ret = abx500_get_register_interruptible(di->dev,
+		AB5500_BANK_FG_BATTCOM_ACC,
+		AB5500_FGDIR_READ0,  &low);
+	if (ret < 0)
+		goto inst_curr_err;
+
+	ret = abx500_get_register_interruptible(di->dev,
+		AB5500_BANK_FG_BATTCOM_ACC,
+		AB5500_FGDIR_READ1,  &high);
+	if (ret < 0)
+		goto inst_curr_err;
+
+	/*
+	 * negative value for Discharging
+	 * convert 2's compliment into decimal
+	 */
+	if (high & 0x10)
+		val = (low | (high << 8) | 0xFFFFE000);
+	else
+		val = (low | (high << 8));
+
+	/*
+	 * Convert to unit value in mA
+	 * R(FGSENSE) = 20 mOhm
+	 * Scaling of LSB: This corresponds fro R(FGSENSE) to a current of
+	 * I = Q/t = 192.7 uC * 4 Hz = 0.77mA
+	 */
+	val = (val * 770) / 1000;
+
+	mutex_unlock(&di->cc_lock);
+
+	if (fg_off) {
+		dev_dbg(di->dev, "%s Disable FG\n", __func__);
+		/* Power-off the CC */
+		ab5500_fg_coulomb_counter(di, false);
+	}
+
+	return val;
+
+inst_curr_err:
+	dev_err(di->dev, "%s Get instanst current failed\n", __func__);
+	mutex_unlock(&di->cc_lock);
+	return ret;
+}
+
+static void ab5500_fg_acc_cur_timer_expired(unsigned long data)
+{
+	struct ab5500_fg *di = (struct ab5500_fg *) data;
+	dev_dbg(di->dev, "Avg current timer expired\n");
+
+	/* Trigger execution of the algorithm instantly */
+	queue_delayed_work(di->fg_wq, &di->fg_acc_cur_work, 0);
+}
+
+/**
+ * ab5500_fg_acc_cur_work() - average battery current
+ * @work:	pointer to the work_struct structure
+ *
+ * Updated the average battery current obtained from the
+ * coulomb counter.
+ */
+static void ab5500_fg_acc_cur_work(struct work_struct *work)
+{
+	int val;
+	int ret;
+	u8 low, med, high, cnt_low, cnt_high;
+
+	struct ab5500_fg *di = container_of(work,
+		struct ab5500_fg, fg_acc_cur_work.work);
+
+	if (!di->flags.fg_enabled) {
+		/* Power-up the CC */
+		ab5500_fg_coulomb_counter(di, true);
+		msleep(250);
+	}
+	mutex_lock(&di->cc_lock);
+	ret = abx500_mask_and_set_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC, AB5500_FG_CONTROL_C,
+			EN_READOUT_MASK, EN_READOUT);
+	if (ret < 0)
+		goto exit;
+	/* If charging read charging registers for accumulated values */
+	if (di->flags.charging) {
+		/* Read CC Sample conversion value Low and high */
+		ret = abx500_get_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC,
+			AB5500_FG_CH0, &low);
+		if (ret < 0)
+			goto exit;
+
+		ret = abx500_get_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC,
+			AB5500_FG_CH1, &med);
+		if (ret < 0)
+			goto exit;
+		ret = abx500_get_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC,
+			AB5500_FG_CH2, &high);
+		if (ret < 0)
+			goto exit;
+		ret = abx500_get_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC,
+			AB5500_FG_VAL_COUNT0, &cnt_low);
+		if (ret < 0)
+			goto exit;
+		ret = abx500_get_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC,
+			AB5500_FG_VAL_COUNT1, &cnt_high);
+		if (ret < 0)
+			goto exit;
+		queue_delayed_work(di->fg_wq, &di->fg_acc_cur_work,
+				di->bat->interval_charging * HZ);
+	} else { /* discharging */
+		/* Read CC Sample conversion value Low and high */
+		ret = abx500_get_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC,
+			AB5500_FG_DIS_CH0, &low);
+		if (ret < 0)
+			goto exit;
+
+		ret = abx500_get_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC,
+			AB5500_FG_DIS_CH1, &med);
+		if (ret < 0)
+			goto exit;
+		ret = abx500_get_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC,
+			AB5500_FG_DIS_CH2, &high);
+		if (ret < 0)
+			goto exit;
+		ret = abx500_get_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC,
+			AB5500_FG_VAL_COUNT0, &cnt_low);
+		if (ret < 0)
+			goto exit;
+		ret = abx500_get_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC,
+			AB5500_FG_VAL_COUNT1, &cnt_high);
+		if (ret < 0)
+			goto exit;
+		queue_delayed_work(di->fg_wq, &di->fg_acc_cur_work,
+				di->bat->interval_not_charging * HZ);
+	}
+	di->fg_samples = (cnt_low | (cnt_high << 8));
+	val = (low | (med << 8) | (high << 16));
+
+	di->accu_charge = (val * QLSB_NANO_AMP_HOURS_X10)/10000;
+	di->avg_curr = (val * FG_LSB_IN_MA) / (di->fg_samples * 1000);
+	di->flags.conv_done = true;
+
+	mutex_unlock(&di->cc_lock);
+
+	queue_work(di->fg_wq, &di->fg_work);
+
+	return;
+exit:
+	dev_err(di->dev,
+		"Failed to read or write gas gauge registers\n");
+	mutex_unlock(&di->cc_lock);
+	queue_work(di->fg_wq, &di->fg_work);
+}
+
+/**
+ * ab5500_fg_bat_voltage() - get battery voltage
+ * @di:		pointer to the ab5500_fg structure
+ *
+ * Returns battery voltage(on success) else error code
+ */
+static int ab5500_fg_bat_voltage(struct ab5500_fg *di)
+{
+	int vbat;
+	static int prev;
+
+	vbat = ab5500_gpadc_convert(di->gpadc, MAIN_BAT_V);
+	if (vbat < 0) {
+		dev_err(di->dev,
+			"%s gpadc conversion failed, using previous value\n",
+			__func__);
+		return prev;
+	}
+
+	prev = vbat;
+	return vbat;
+}
+
+/**
+ * ab5500_fg_volt_to_capacity() - Voltage based capacity
+ * @di:		pointer to the ab5500_fg structure
+ * @voltage:	The voltage to convert to a capacity
+ *
+ * Returns battery capacity in per mille based on voltage
+ */
+static int ab5500_fg_volt_to_capacity(struct ab5500_fg *di, int voltage)
+{
+	int i, tbl_size;
+	struct abx500_v_to_cap *tbl;
+	int cap = 0;
+
+	tbl = di->bat->bat_type[di->bat->batt_id].v_to_cap_tbl,
+	tbl_size = di->bat->bat_type[di->bat->batt_id].n_v_cap_tbl_elements;
+
+	for (i = 0; i < tbl_size; ++i) {
+		if (di->vbat < tbl[i].voltage && di->vbat > tbl[i+1].voltage)
+			di->v_to_cap = tbl[i].capacity;
+	}
+
+	for (i = 0; i < tbl_size; ++i) {
+		if (voltage > tbl[i].voltage)
+			break;
+	}
+
+	if ((i > 0) && (i < tbl_size)) {
+		cap = interpolate(voltage,
+			tbl[i].voltage,
+			tbl[i].capacity * 10,
+			tbl[i-1].voltage,
+			tbl[i-1].capacity * 10);
+	} else if (i == 0) {
+		cap = 1000;
+	} else {
+		cap = 0;
+	}
+
+	dev_dbg(di->dev, "%s Vbat: %d, Cap: %d per mille",
+		__func__, voltage, cap);
+
+	return cap;
+}
+
+/**
+ * ab5500_fg_uncomp_volt_to_capacity() - Uncompensated voltage based capacity
+ * @di:		pointer to the ab5500_fg structure
+ *
+ * Returns battery capacity based on battery voltage that is not compensated
+ * for the voltage drop due to the load
+ */
+static int ab5500_fg_uncomp_volt_to_capacity(struct ab5500_fg *di)
+{
+	di->vbat = ab5500_fg_bat_voltage(di);
+	return ab5500_fg_volt_to_capacity(di, di->vbat);
+}
+
+/**
+ * ab5500_fg_load_comp_volt_to_capacity() - Load compensated voltage based capacity
+ * @di:		pointer to the ab5500_fg structure
+ *
+ * Returns battery capacity based on battery voltage that is load compensated
+ * for the voltage drop
+ */
+static int ab5500_fg_load_comp_volt_to_capacity(struct ab5500_fg *di)
+{
+	int vbat_comp;
+
+	di->inst_curr = ab5500_fg_inst_curr(di);
+	di->vbat = ab5500_fg_bat_voltage(di);
+
+	/* Use Ohms law to get the load compensated voltage */
+	vbat_comp = di->vbat - (di->inst_curr *
+		di->bat->bat_type[di->bat->batt_id].battery_resistance) / 1000;
+
+	dev_dbg(di->dev, "%s Measured Vbat: %dmV,Compensated Vbat %dmV, "
+		"R: %dmOhm, Current: %dmA\n",
+		__func__,
+		di->vbat,
+		vbat_comp,
+		di->bat->bat_type[di->bat->batt_id].battery_resistance,
+		di->inst_curr);
+
+	return ab5500_fg_volt_to_capacity(di, vbat_comp);
+}
+
+/**
+ * ab5500_fg_convert_mah_to_permille() - Capacity in mAh to permille
+ * @di:		pointer to the ab5500_fg structure
+ * @cap_mah:	capacity in mAh
+ *
+ * Converts capacity in mAh to capacity in permille
+ */
+static int ab5500_fg_convert_mah_to_permille(struct ab5500_fg *di, int cap_mah)
+{
+	return (cap_mah * 1000) / di->bat_cap.max_mah_design;
+}
+
+/**
+ * ab5500_fg_convert_permille_to_mah() - Capacity in permille to mAh
+ * @di:		pointer to the ab5500_fg structure
+ * @cap_pm:	capacity in permille
+ *
+ * Converts capacity in permille to capacity in mAh
+ */
+static int ab5500_fg_convert_permille_to_mah(struct ab5500_fg *di, int cap_pm)
+{
+	return cap_pm * di->bat_cap.max_mah_design / 1000;
+}
+
+/**
+ * ab5500_fg_convert_mah_to_uwh() - Capacity in mAh to uWh
+ * @di:		pointer to the ab5500_fg structure
+ * @cap_mah:	capacity in mAh
+ *
+ * Converts capacity in mAh to capacity in uWh
+ */
+static int ab5500_fg_convert_mah_to_uwh(struct ab5500_fg *di, int cap_mah)
+{
+	u64 div_res;
+	u32 div_rem;
+
+	div_res = ((u64) cap_mah) * ((u64) di->vbat_nom);
+	div_rem = do_div(div_res, 1000);
+
+	/* Make sure to round upwards if necessary */
+	if (div_rem >= 1000 / 2)
+		div_res++;
+
+	return (int) div_res;
+}
+
+/**
+ * ab5500_fg_calc_cap_charging() - Calculate remaining capacity while charging
+ * @di:		pointer to the ab5500_fg structure
+ *
+ * Return the capacity in mAh based on previous calculated capcity and the FG
+ * accumulator register value. The filter is filled with this capacity
+ */
+static int ab5500_fg_calc_cap_charging(struct ab5500_fg *di)
+{
+	dev_dbg(di->dev, "%s cap_mah %d accu_charge %d\n",
+		__func__,
+		di->bat_cap.mah,
+		di->accu_charge);
+
+	/* Capacity should not be less than 0 */
+	if (di->bat_cap.mah + di->accu_charge > 0)
+		di->bat_cap.mah += di->accu_charge;
+	else
+		di->bat_cap.mah = 0;
+
+	/*
+	 * We force capacity to 100% as long as the algorithm
+	 * reports that it's full.
+	*/
+	if (di->bat_cap.mah >= di->bat_cap.max_mah_design ||
+		di->flags.fully_charged)
+		di->bat_cap.mah = di->bat_cap.max_mah_design;
+
+	ab5500_fg_fill_cap_sample(di, di->bat_cap.mah);
+	di->bat_cap.permille =
+		ab5500_fg_convert_mah_to_permille(di, di->bat_cap.mah);
+
+	/* We need to update battery voltage and inst current when charging */
+	di->vbat = ab5500_fg_bat_voltage(di);
+	di->inst_curr = ab5500_fg_inst_curr(di);
+
+	return di->bat_cap.mah;
+}
+
+/**
+ * ab5500_fg_calc_cap_discharge_voltage() - Capacity in discharge with voltage
+ * @di:		pointer to the ab5500_fg structure
+ * @comp:	if voltage should be load compensated before capacity calc
+ *
+ * Return the capacity in mAh based on the battery voltage. The voltage can
+ * either be load compensated or not. This value is added to the filter and a
+ * new mean value is calculated and returned.
+ */
+static int ab5500_fg_calc_cap_discharge_voltage(struct ab5500_fg *di, bool comp)
+{
+	int permille, mah;
+
+	if (comp)
+		permille = ab5500_fg_load_comp_volt_to_capacity(di);
+	else
+		permille = ab5500_fg_uncomp_volt_to_capacity(di);
+
+	mah = ab5500_fg_convert_permille_to_mah(di, permille);
+
+	di->bat_cap.mah = ab5500_fg_add_cap_sample(di, mah);
+	di->bat_cap.permille =
+		ab5500_fg_convert_mah_to_permille(di, di->bat_cap.mah);
+
+	return di->bat_cap.mah;
+}
+
+/**
+ * ab5500_fg_calc_cap_discharge_fg() - Capacity in discharge with FG
+ * @di:		pointer to the ab5500_fg structure
+ *
+ * Return the capacity in mAh based on previous calculated capcity and the FG
+ * accumulator register value. This value is added to the filter and a
+ * new mean value is calculated and returned.
+ */
+static int ab5500_fg_calc_cap_discharge_fg(struct ab5500_fg *di)
+{
+	int permille_volt, permille;
+
+	dev_dbg(di->dev, "%s cap_mah %d accu_charge %d\n",
+		__func__,
+		di->bat_cap.mah,
+		di->accu_charge);
+
+	/* Capacity should not be less than 0 */
+	if (di->bat_cap.mah + di->accu_charge > 0)
+		di->bat_cap.mah += di->accu_charge;
+	else
+		di->bat_cap.mah = 0;
+
+	if (di->bat_cap.mah >= di->bat_cap.max_mah_design)
+		di->bat_cap.mah = di->bat_cap.max_mah_design;
+
+	/*
+	 * Check against voltage based capacity. It can not be lower
+	 * than what the uncompensated voltage says
+	 */
+	permille = ab5500_fg_convert_mah_to_permille(di, di->bat_cap.mah);
+	permille_volt = ab5500_fg_uncomp_volt_to_capacity(di);
+
+	if (permille < permille_volt) {
+		di->bat_cap.permille = permille_volt;
+		di->bat_cap.mah = ab5500_fg_convert_permille_to_mah(di,
+			di->bat_cap.permille);
+
+		dev_dbg(di->dev, "%s voltage based: perm %d perm_volt %d\n",
+			__func__,
+			permille,
+			permille_volt);
+
+		ab5500_fg_fill_cap_sample(di, di->bat_cap.mah);
+	} else {
+		ab5500_fg_fill_cap_sample(di, di->bat_cap.mah);
+		di->bat_cap.permille =
+			ab5500_fg_convert_mah_to_permille(di, di->bat_cap.mah);
+	}
+
+	return di->bat_cap.mah;
+}
+
+/**
+ * ab5500_fg_capacity_level() - Get the battery capacity level
+ * @di:		pointer to the ab5500_fg structure
+ *
+ * Get the battery capacity level based on the capacity in percent
+ */
+static int ab5500_fg_capacity_level(struct ab5500_fg *di)
+{
+	int ret, percent;
+
+	percent = di->bat_cap.permille / 10;
+
+	if (percent <= di->bat->cap_levels->critical ||
+		di->flags.low_bat)
+		ret = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
+	else if (percent <= di->bat->cap_levels->low)
+		ret = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
+	else if (percent <= di->bat->cap_levels->normal)
+		ret = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
+	else if (percent <= di->bat->cap_levels->high)
+		ret = POWER_SUPPLY_CAPACITY_LEVEL_HIGH;
+	else
+		ret = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
+
+	return ret;
+}
+
+/**
+ * ab5500_fg_check_capacity_limits() - Check if capacity has changed
+ * @di:		pointer to the ab5500_fg structure
+ * @init:	capacity is allowed to go up in init mode
+ *
+ * Check if capacity or capacity limit has changed and notify the system
+ * about it using the power_supply framework
+ */
+static void ab5500_fg_check_capacity_limits(struct ab5500_fg *di, bool init)
+{
+	bool changed = false;
+
+	di->bat_cap.level = ab5500_fg_capacity_level(di);
+
+	if (di->bat_cap.level != di->bat_cap.prev_level) {
+		/*
+		 * We do not allow reported capacity level to go up
+		 * unless we're charging or if we're in init
+		 */
+		if (!(!di->flags.charging && di->bat_cap.level >
+			di->bat_cap.prev_level) || init) {
+			dev_dbg(di->dev, "level changed from %d to %d\n",
+				di->bat_cap.prev_level,
+				di->bat_cap.level);
+			di->bat_cap.prev_level = di->bat_cap.level;
+			changed = true;
+		} else {
+			dev_dbg(di->dev, "level not allowed to go up "
+				"since no charger is connected: %d to %d\n",
+				di->bat_cap.prev_level,
+				di->bat_cap.level);
+		}
+	}
+
+	/*
+	 * If we have received the LOW_BAT IRQ, set capacity to 0 to initiate
+	 * shutdown
+	 */
+	if (di->flags.low_bat) {
+		dev_dbg(di->dev, "Battery low, set capacity to 0\n");
+		di->bat_cap.prev_percent = 0;
+		di->bat_cap.permille = 0;
+		di->bat_cap.prev_mah = 0;
+		di->bat_cap.mah = 0;
+		changed = true;
+	} else if (di->bat_cap.prev_percent != di->bat_cap.permille / 10) {
+		if (di->bat_cap.permille / 10 == 0) {
+			/*
+			 * We will not report 0% unless we've got
+			 * the LOW_BAT IRQ, no matter what the FG
+			 * algorithm says.
+			 */
+			di->bat_cap.prev_percent = 1;
+			di->bat_cap.permille = 1;
+			di->bat_cap.prev_mah = 1;
+			di->bat_cap.mah = 1;
+
+			changed = true;
+		} else if (!(!di->flags.charging &&
+			(di->bat_cap.permille / 10) >
+			di->bat_cap.prev_percent) || init) {
+			/*
+			 * We do not allow reported capacity to go up
+			 * unless we're charging or if we're in init
+			 */
+			dev_dbg(di->dev,
+				"capacity changed from %d to %d (%d)\n",
+				di->bat_cap.prev_percent,
+				di->bat_cap.permille / 10,
+				di->bat_cap.permille);
+			di->bat_cap.prev_percent = di->bat_cap.permille / 10;
+			di->bat_cap.prev_mah = di->bat_cap.mah;
+
+			changed = true;
+		} else {
+			dev_dbg(di->dev, "capacity not allowed to go up since "
+				"no charger is connected: %d to %d (%d)\n",
+				di->bat_cap.prev_percent,
+				di->bat_cap.permille / 10,
+				di->bat_cap.permille);
+		}
+	}
+
+	if (changed)
+		power_supply_changed(&di->fg_psy);
+
+}
+
+static void ab5500_fg_charge_state_to(struct ab5500_fg *di,
+	enum ab5500_fg_charge_state new_state)
+{
+	dev_dbg(di->dev, "Charge state from %d [%s] to %d [%s]\n",
+		di->charge_state,
+		charge_state[di->charge_state],
+		new_state,
+		charge_state[new_state]);
+
+	di->charge_state = new_state;
+}
+
+static void ab5500_fg_discharge_state_to(struct ab5500_fg *di,
+	enum ab5500_fg_charge_state new_state)
+{
+	dev_dbg(di->dev, "Disharge state from %d [%s] to %d [%s]\n",
+		di->discharge_state,
+		discharge_state[di->discharge_state],
+		new_state,
+		discharge_state[new_state]);
+
+	di->discharge_state = new_state;
+}
+
+/**
+ * ab5500_fg_algorithm_charging() - FG algorithm for when charging
+ * @di:		pointer to the ab5500_fg structure
+ *
+ * Battery capacity calculation state machine for when we're charging
+ */
+static void ab5500_fg_algorithm_charging(struct ab5500_fg *di)
+{
+	/*
+	 * If we change to discharge mode
+	 * we should start with recovery
+	 */
+	if (di->discharge_state != AB5500_FG_DISCHARGE_INIT_RECOVERY)
+		ab5500_fg_discharge_state_to(di,
+			AB5500_FG_DISCHARGE_INIT_RECOVERY);
+
+	switch (di->charge_state) {
+	case AB5500_FG_CHARGE_INIT:
+		di->fg_samples = SEC_TO_SAMPLE(
+			di->bat->fg_params->accu_charging);
+
+		ab5500_fg_coulomb_counter(di, true);
+		ab5500_fg_charge_state_to(di, AB5500_FG_CHARGE_READOUT);
+
+		break;
+
+	case AB5500_FG_CHARGE_READOUT:
+		/*
+		 * Read the FG and calculate the new capacity
+		 */
+		mutex_lock(&di->cc_lock);
+		if (!di->flags.conv_done) {
+			/* Wasn't the CC IRQ that got us here */
+			mutex_unlock(&di->cc_lock);
+			dev_dbg(di->dev, "%s CC conv not done\n",
+				__func__);
+
+			break;
+		}
+		di->flags.conv_done = false;
+		mutex_unlock(&di->cc_lock);
+
+		ab5500_fg_calc_cap_charging(di);
+
+		break;
+
+	default:
+		break;
+	}
+
+	/* Check capacity limits */
+	ab5500_fg_check_capacity_limits(di, false);
+}
+
+/**
+ * ab5500_fg_algorithm_discharging() - FG algorithm for when discharging
+ * @di:		pointer to the ab5500_fg structure
+ *
+ * Battery capacity calculation state machine for when we're discharging
+ */
+static void ab5500_fg_algorithm_discharging(struct ab5500_fg *di)
+{
+	int sleep_time;
+
+	/* If we change to charge mode we should start with init */
+	if (di->charge_state != AB5500_FG_CHARGE_INIT)
+		ab5500_fg_charge_state_to(di, AB5500_FG_CHARGE_INIT);
+
+	switch (di->discharge_state) {
+	case AB5500_FG_DISCHARGE_INIT:
+		/* We use the FG IRQ to work on */
+		di->init_cnt = 0;
+		di->fg_samples = SEC_TO_SAMPLE(di->bat->fg_params->init_timer);
+		ab5500_fg_coulomb_counter(di, true);
+		ab5500_fg_discharge_state_to(di,
+			AB5500_FG_DISCHARGE_INITMEASURING);
+
+		/* Intentional fallthrough */
+	case AB5500_FG_DISCHARGE_INITMEASURING:
+		/*
+		 * Discard a number of samples during startup.
+		 * After that, use compensated voltage for a few
+		 * samples to get an initial capacity.
+		 * Then go to READOUT
+		 */
+		sleep_time = di->bat->fg_params->init_timer;
+
+		/* Discard the first [x] seconds */
+		if (di->init_cnt >
+			di->bat->fg_params->init_discard_time) {
+
+			ab5500_fg_calc_cap_discharge_voltage(di, true);
+
+			ab5500_fg_check_capacity_limits(di, true);
+		}
+
+		di->init_cnt += sleep_time;
+		if (di->init_cnt >
+			di->bat->fg_params->init_total_time) {
+			di->fg_samples = SEC_TO_SAMPLE(
+				di->bat->fg_params->accu_high_curr);
+
+			ab5500_fg_coulomb_counter(di, true);
+			ab5500_fg_discharge_state_to(di,
+				AB5500_FG_DISCHARGE_READOUT);
+		}
+
+		break;
+
+	case AB5500_FG_DISCHARGE_INIT_RECOVERY:
+		di->recovery_cnt = 0;
+		di->recovery_needed = true;
+		ab5500_fg_discharge_state_to(di,
+			AB5500_FG_DISCHARGE_RECOVERY);
+
+		/* Intentional fallthrough */
+
+	case AB5500_FG_DISCHARGE_RECOVERY:
+		sleep_time = di->bat->fg_params->recovery_sleep_timer;
+
+		/*
+		 * We should check the power consumption
+		 * If low, go to READOUT (after x min) or
+		 * RECOVERY_SLEEP if time left.
+		 * If high, go to READOUT
+		 */
+		di->inst_curr = ab5500_fg_inst_curr(di);
+
+		if (ab5500_fg_is_low_curr(di, di->inst_curr)) {
+			if (di->recovery_cnt >
+				di->bat->fg_params->recovery_total_time) {
+				di->fg_samples = SEC_TO_SAMPLE(
+					di->bat->fg_params->accu_high_curr);
+				ab5500_fg_coulomb_counter(di, true);
+				ab5500_fg_discharge_state_to(di,
+					AB5500_FG_DISCHARGE_READOUT);
+				di->recovery_needed = false;
+			} else {
+				queue_delayed_work(di->fg_wq,
+					&di->fg_periodic_work,
+					sleep_time * HZ);
+			}
+			di->recovery_cnt += sleep_time;
+		} else {
+			di->fg_samples = SEC_TO_SAMPLE(
+				di->bat->fg_params->accu_high_curr);
+			ab5500_fg_coulomb_counter(di, true);
+			ab5500_fg_discharge_state_to(di,
+				AB5500_FG_DISCHARGE_READOUT);
+		}
+
+		break;
+
+	case AB5500_FG_DISCHARGE_READOUT:
+		di->inst_curr = ab5500_fg_inst_curr(di);
+
+		if (ab5500_fg_is_low_curr(di, di->inst_curr)) {
+			/* Detect mode change */
+			if (di->high_curr_mode) {
+				di->high_curr_mode = false;
+				di->high_curr_cnt = 0;
+			}
+
+			if (di->recovery_needed) {
+				ab5500_fg_discharge_state_to(di,
+					AB5500_FG_DISCHARGE_RECOVERY);
+
+				queue_delayed_work(di->fg_wq,
+					&di->fg_periodic_work,
+					0);
+
+				break;
+			}
+
+			ab5500_fg_calc_cap_discharge_voltage(di, true);
+		} else {
+			mutex_lock(&di->cc_lock);
+			if (!di->flags.conv_done) {
+				/* Wasn't the CC IRQ that got us here */
+				mutex_unlock(&di->cc_lock);
+				dev_dbg(di->dev, "%s CC conv not done\n",
+					__func__);
+
+				break;
+			}
+			di->flags.conv_done = false;
+			mutex_unlock(&di->cc_lock);
+
+			/* Detect mode change */
+			if (!di->high_curr_mode) {
+				di->high_curr_mode = true;
+				di->high_curr_cnt = 0;
+			}
+
+			di->high_curr_cnt +=
+				di->bat->fg_params->accu_high_curr;
+			if (di->high_curr_cnt >
+				di->bat->fg_params->high_curr_time)
+				di->recovery_needed = true;
+
+			ab5500_fg_calc_cap_discharge_fg(di);
+		}
+
+		ab5500_fg_check_capacity_limits(di, false);
+
+		break;
+
+	case AB5500_FG_DISCHARGE_WAKEUP:
+		ab5500_fg_coulomb_counter(di, true);
+		di->inst_curr = ab5500_fg_inst_curr(di);
+
+		ab5500_fg_calc_cap_discharge_voltage(di, true);
+
+		di->fg_samples = SEC_TO_SAMPLE(
+			di->bat->fg_params->accu_high_curr);
+		/* Re-program number of samples set above */
+		ab5500_fg_coulomb_counter(di, true);
+		ab5500_fg_discharge_state_to(di, AB5500_FG_DISCHARGE_READOUT);
+
+		ab5500_fg_check_capacity_limits(di, false);
+
+		break;
+
+	default:
+		break;
+	}
+}
+
+/**
+ * ab5500_fg_algorithm_calibrate() - Internal columb counter offset calibration
+ * @di:		pointer to the ab5500_fg structure
+ *
+ */
+static void ab5500_fg_algorithm_calibrate(struct ab5500_fg *di)
+{
+	int ret;
+
+	switch (di->calib_state) {
+	case AB5500_FG_CALIB_INIT:
+		dev_dbg(di->dev, "Calibration ongoing...\n");
+		/* TODO: For Cut 1.1 no calibration */
+		ret = abx500_mask_and_set_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC, AB5500_FG_CONTROL_A,
+			FG_ACC_RESET_ON_READ_MASK, FG_ACC_RESET_ON_READ);
+		if (ret)
+			goto err;
+		di->calib_state = AB5500_FG_CALIB_WAIT;
+		break;
+	case AB5500_FG_CALIB_END:
+		di->flags.calibrate = false;
+		dev_dbg(di->dev, "Calibration done...\n");
+		queue_delayed_work(di->fg_wq, &di->fg_periodic_work, 0);
+		break;
+	case AB5500_FG_CALIB_WAIT:
+		dev_dbg(di->dev, "Calibration WFI\n");
+	default:
+		break;
+	}
+	return;
+err:
+	/* Something went wrong, don't calibrate then */
+	dev_err(di->dev, "failed to calibrate the CC\n");
+	di->flags.calibrate = false;
+	di->calib_state = AB5500_FG_CALIB_INIT;
+	queue_delayed_work(di->fg_wq, &di->fg_periodic_work, 0);
+}
+
+/**
+ * ab5500_fg_algorithm() - Entry point for the FG algorithm
+ * @di:		pointer to the ab5500_fg structure
+ *
+ * Entry point for the battery capacity calculation state machine
+ */
+static void ab5500_fg_algorithm(struct ab5500_fg *di)
+{
+	if (di->flags.calibrate)
+		ab5500_fg_algorithm_calibrate(di);
+	else {
+		if (di->flags.charging)
+			ab5500_fg_algorithm_charging(di);
+		else
+			ab5500_fg_algorithm_discharging(di);
+	}
+
+	dev_dbg(di->dev, "[FG_DATA] %d %d %d %d %d %d %d %d %d "
+		"%d %d %d %d %d %d %d\n",
+		di->bat_cap.max_mah_design,
+		di->bat_cap.mah,
+		di->bat_cap.permille,
+		di->bat_cap.level,
+		di->bat_cap.prev_mah,
+		di->bat_cap.prev_percent,
+		di->bat_cap.prev_level,
+		di->vbat,
+		di->inst_curr,
+		di->avg_curr,
+		di->accu_charge,
+		di->flags.charging,
+		di->charge_state,
+		di->discharge_state,
+		di->high_curr_mode,
+		di->recovery_needed);
+}
+
+/**
+ * ab5500_fg_periodic_work() - Run the FG state machine periodically
+ * @work:	pointer to the work_struct structure
+ *
+ * Work queue function for periodic work
+ */
+static void ab5500_fg_periodic_work(struct work_struct *work)
+{
+	struct ab5500_fg *di = container_of(work, struct ab5500_fg,
+		fg_periodic_work.work);
+
+	if (di->init_capacity) {
+		/* A dummy read that will return 0 */
+		di->inst_curr = ab5500_fg_inst_curr(di);
+		/* Get an initial capacity calculation */
+		ab5500_fg_calc_cap_discharge_voltage(di, true);
+		ab5500_fg_check_capacity_limits(di, true);
+		di->init_capacity = false;
+		queue_delayed_work(di->fg_wq, &di->fg_periodic_work, 0);
+	} else
+		ab5500_fg_algorithm(di);
+}
+
+/**
+ * ab5500_fg_low_bat_work() - Check LOW_BAT condition
+ * @work:	pointer to the work_struct structure
+ *
+ * Work queue function for checking the LOW_BAT condition
+ */
+static void ab5500_fg_low_bat_work(struct work_struct *work)
+{
+	int vbat;
+
+	struct ab5500_fg *di = container_of(work, struct ab5500_fg,
+		fg_low_bat_work.work);
+
+	vbat = ab5500_fg_bat_voltage(di);
+
+	/* Check if LOW_BAT still fulfilled */
+	if (vbat < di->bat->fg_params->lowbat_threshold) {
+		di->flags.low_bat = true;
+		dev_warn(di->dev, "Battery voltage still LOW\n");
+
+		/*
+		 * We need to re-schedule this check to be able to detect
+		 * if the voltage increases again during charging
+		 */
+		queue_delayed_work(di->fg_wq, &di->fg_low_bat_work,
+			round_jiffies(LOW_BAT_CHECK_INTERVAL));
+	} else {
+		di->flags.low_bat = false;
+		dev_warn(di->dev, "Battery voltage OK again\n");
+	}
+
+	/* This is needed to dispatch LOW_BAT */
+	ab5500_fg_check_capacity_limits(di, false);
+
+	/* Set this flag to check if LOW_BAT IRQ still occurs */
+	di->flags.low_bat_delay = false;
+}
+
+/**
+ * ab5500_fg_instant_work() - Run the FG state machine instantly
+ * @work:	pointer to the work_struct structure
+ *
+ * Work queue function for instant work
+ */
+static void ab5500_fg_instant_work(struct work_struct *work)
+{
+	struct ab5500_fg *di = container_of(work, struct ab5500_fg, fg_work);
+
+	ab5500_fg_algorithm(di);
+}
+
+/**
+ * ab5500_fg_get_property() - get the fg properties
+ * @psy:	pointer to the power_supply structure
+ * @psp:	pointer to the power_supply_property structure
+ * @val:	pointer to the power_supply_propval union
+ *
+ * This function gets called when an application tries to get the
+ * fg properties by reading the sysfs files.
+ * voltage_now:		battery voltage
+ * current_now:		battery instant current
+ * current_avg:		battery average current
+ * charge_full_design:	capacity where battery is considered full
+ * charge_now:		battery capacity in nAh
+ * capacity:		capacity in percent
+ * capacity_level:	capacity level
+ *
+ * Returns error code in case of failure else 0 on success
+ */
+static int ab5500_fg_get_property(struct power_supply *psy,
+	enum power_supply_property psp,
+	union power_supply_propval *val)
+{
+	struct ab5500_fg *di;
+	int i, tbl_size;
+	struct abx500_v_to_cap *tbl;
+
+	di = to_ab5500_fg_device_info(psy);
+
+	/*
+	 * If battery is identified as unknown and charging of unknown
+	 * batteries is disabled, we always report 100% capacity and
+	 * capacity level UNKNOWN, since we can't calculate
+	 * remaining capacity
+	 */
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+		if (di->flags.bat_ovv)
+			val->intval = 47500000;
+		else
+			val->intval = ab5500_gpadc_convert
+						(di->gpadc, MAIN_BAT_V) * 1000;
+		break;
+	case POWER_SUPPLY_PROP_CURRENT_NOW:
+		di->inst_curr = ab5500_fg_inst_curr(di);
+		val->intval = di->inst_curr * 1000;
+		break;
+	case POWER_SUPPLY_PROP_CURRENT_AVG:
+		val->intval = di->avg_curr * 1000;
+		break;
+	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
+		val->intval = ab5500_fg_convert_mah_to_uwh(di,
+				di->bat_cap.max_mah_design);
+		break;
+	case POWER_SUPPLY_PROP_ENERGY_FULL:
+		val->intval = ab5500_fg_convert_mah_to_uwh(di,
+				di->bat_cap.max_mah);
+		break;
+	case POWER_SUPPLY_PROP_ENERGY_NOW:
+		if (di->flags.batt_unknown && !di->bat->chg_unknown_bat)
+			val->intval = ab5500_fg_convert_mah_to_uwh(di,
+					di->bat_cap.max_mah);
+		else
+			val->intval = ab5500_fg_convert_mah_to_uwh(di,
+					di->bat_cap.prev_mah);
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
+		val->intval = di->bat_cap.max_mah_design;
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_FULL:
+		val->intval = di->bat_cap.max_mah;
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_NOW:
+		if (di->flags.batt_unknown && !di->bat->chg_unknown_bat)
+			val->intval = di->bat_cap.max_mah;
+		else
+			val->intval = di->bat_cap.prev_mah;
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY:
+		if (di->flags.batt_unknown && !di->bat->chg_unknown_bat)
+			val->intval = 100;
+		else if (di->bat->bat_type[di->bat->batt_id].v_to_cap_tbl) {
+			tbl = di->bat->bat_type[di->bat->batt_id].v_to_cap_tbl,
+			tbl_size = di->bat->bat_type[
+				di->bat->batt_id].n_v_cap_tbl_elements;
+
+			for (i = 0; i < tbl_size; ++i) {
+				if (di->vbat < tbl[i].voltage &&
+						di->vbat > tbl[i+1].voltage) {
+					di->v_to_cap = tbl[i].capacity;
+					break;
+				}
+			}
+			val->intval = di->v_to_cap;
+		} else
+			val->intval = di->bat_cap.prev_percent;
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
+		if (di->flags.batt_unknown && !di->bat->chg_unknown_bat)
+			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_UNKNOWN;
+		else
+			val->intval = di->bat_cap.prev_level;
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int ab5500_fg_get_ext_psy_data(struct device *dev, void *data)
+{
+	struct power_supply *psy;
+	struct power_supply *ext;
+	struct ab5500_fg *di;
+	union power_supply_propval ret;
+	int i, j;
+	bool psy_found = false;
+
+	psy = (struct power_supply *)data;
+	ext = dev_get_drvdata(dev);
+	di = to_ab5500_fg_device_info(psy);
+
+	/*
+	 * For all psy where the name of your driver
+	 * appears in any supplied_to
+	 */
+	for (i = 0; i < ext->num_supplicants; i++) {
+		if (!strcmp(ext->supplied_to[i], psy->name))
+			psy_found = true;
+	}
+
+	if (!psy_found)
+		return 0;
+
+	/* Go through all properties for the psy */
+	for (j = 0; j < ext->num_properties; j++) {
+		enum power_supply_property prop;
+		prop = ext->properties[j];
+
+		if (ext->get_property(ext, prop, &ret))
+			continue;
+
+		switch (prop) {
+		case POWER_SUPPLY_PROP_STATUS:
+			switch (ext->type) {
+			case POWER_SUPPLY_TYPE_BATTERY:
+				switch (ret.intval) {
+				case POWER_SUPPLY_STATUS_UNKNOWN:
+				case POWER_SUPPLY_STATUS_DISCHARGING:
+				case POWER_SUPPLY_STATUS_NOT_CHARGING:
+					if (!di->flags.charging)
+						break;
+					di->flags.charging = false;
+					di->flags.fully_charged = false;
+					queue_work(di->fg_wq, &di->fg_work);
+					break;
+				case POWER_SUPPLY_STATUS_FULL:
+					if (di->flags.fully_charged)
+						break;
+					di->flags.fully_charged = true;
+					/* Save current capacity as maximum */
+					di->bat_cap.max_mah = di->bat_cap.mah;
+					queue_work(di->fg_wq, &di->fg_work);
+					break;
+				case POWER_SUPPLY_STATUS_CHARGING:
+					if (di->flags.charging)
+						break;
+					di->flags.charging = true;
+					di->flags.fully_charged = false;
+					queue_work(di->fg_wq, &di->fg_work);
+					break;
+				};
+			default:
+				break;
+			};
+			break;
+		case POWER_SUPPLY_PROP_TECHNOLOGY:
+			switch (ext->type) {
+			case POWER_SUPPLY_TYPE_BATTERY:
+				if (ret.intval)
+					di->flags.batt_unknown = false;
+				else
+					di->flags.batt_unknown = true;
+				break;
+			default:
+				break;
+			}
+			break;
+		default:
+			break;
+		}
+	}
+	return 0;
+}
+
+static int ab5500_fg_bat_v_trig(int mux)
+{
+	struct ab5500_fg *di = ab5500_fg_get();
+
+	/* check if the battery voltage is below low threshold */
+	if (di->vbat < 2700) {
+		dev_warn(di->dev, "Battery voltage is below LOW threshold\n");
+		di->flags.low_bat_delay = true;
+		/*
+		 * Start a timer to check LOW_BAT again after some time
+		 * This is done to avoid shutdown on single voltage dips
+		 */
+		queue_delayed_work(di->fg_wq, &di->fg_low_bat_work,
+			round_jiffies(LOW_BAT_CHECK_INTERVAL));
+	}
+	/* check if battery votlage is above OVV */
+	else if (di->vbat > 4200) {
+		dev_dbg(di->dev, "Battery OVV\n");
+		di->flags.bat_ovv = true;
+
+		power_supply_changed(&di->fg_psy);
+	} else
+		return -EINVAL;
+
+	return 0;
+}
+
+/**
+ * ab5500_fg_init_hw_registers() - Set up FG related registers
+ * @di:		pointer to the ab5500_fg structure
+ *
+ * Set up battery OVV, low battery voltage registers
+ */
+static int ab5500_fg_init_hw_registers(struct ab5500_fg *di)
+{
+	int ret;
+	struct adc_auto_input *auto_ip;
+
+	auto_ip = kzalloc(sizeof(struct adc_auto_input), GFP_KERNEL);
+	if (!auto_ip) {
+		dev_err(di->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	auto_ip->mux = MAIN_BAT_V;
+	auto_ip->freq = MS500;
+	auto_ip->min = 2700;
+	auto_ip->max = 4200;
+	auto_ip->auto_adc_callback = ab5500_fg_bat_v_trig;
+	di->gpadc_auto = auto_ip;
+	ret = ab5500_gpadc_convert_auto(di->gpadc, di->gpadc_auto);
+	if (ret)
+		dev_err(di->dev,
+			"failed to set auto trigger for battery votlage\n");
+	/* set End Of Charge current to 247mA */
+	ret = abx500_set_register_interruptible(di->dev,
+			AB5500_BANK_FG_BATTCOM_ACC, AB5500_FG_EOC, EOC_52_mA);
+	return ret;
+}
+
+/**
+ * ab5500_fg_external_power_changed() - callback for power supply changes
+ * @psy:       pointer to the structure power_supply
+ *
+ * This function is the entry point of the pointer external_power_changed
+ * of the structure power_supply.
+ * This function gets executed when there is a change in any external power
+ * supply that this driver needs to be notified of.
+ */
+static void ab5500_fg_external_power_changed(struct power_supply *psy)
+{
+	struct ab5500_fg *di = to_ab5500_fg_device_info(psy);
+
+	class_for_each_device(power_supply_class, NULL,
+		&di->fg_psy, ab5500_fg_get_ext_psy_data);
+}
+
+#if defined(CONFIG_PM)
+static int ab5500_fg_resume(struct platform_device *pdev)
+{
+	struct ab5500_fg *di = platform_get_drvdata(pdev);
+
+	/*
+	 * Change state if we're not charging. If we're charging we will wake
+	 * up on the FG IRQ
+	 */
+	if (!di->flags.charging) {
+		ab5500_fg_discharge_state_to(di, AB5500_FG_DISCHARGE_WAKEUP);
+		queue_work(di->fg_wq, &di->fg_work);
+	}
+
+	return 0;
+}
+
+static int ab5500_fg_suspend(struct platform_device *pdev,
+	pm_message_t state)
+{
+	struct ab5500_fg *di = platform_get_drvdata(pdev);
+
+	flush_delayed_work(&di->fg_periodic_work);
+
+	/*
+	 * If the FG is enabled we will disable it before going to suspend
+	 * only if we're not charging
+	 */
+	if (di->flags.fg_enabled && !di->flags.charging)
+		ab5500_fg_coulomb_counter(di, false);
+
+	return 0;
+}
+#else
+#define ab5500_fg_suspend      NULL
+#define ab5500_fg_resume       NULL
+#endif
+
+static int __devexit ab5500_fg_remove(struct platform_device *pdev)
+{
+	int ret = 0;
+	struct ab5500_fg *di = platform_get_drvdata(pdev);
+
+	/* Disable coulomb counter */
+	ret = ab5500_fg_coulomb_counter(di, false);
+	if (ret)
+		dev_err(di->dev, "failed to disable coulomb counter\n");
+
+	destroy_workqueue(di->fg_wq);
+
+	flush_scheduled_work();
+	power_supply_unregister(&di->fg_psy);
+	platform_set_drvdata(pdev, NULL);
+	kfree(di->gpadc_auto);
+	kfree(di);
+	return ret;
+}
+
+static int __devinit ab5500_fg_probe(struct platform_device *pdev)
+{
+	struct abx500_bm_plat_data *plat_data;
+	int ret = 0;
+
+	struct ab5500_fg *di =
+		kzalloc(sizeof(struct ab5500_fg), GFP_KERNEL);
+	if (!di)
+		return -ENOMEM;
+
+	mutex_init(&di->cc_lock);
+
+	/* get parent data */
+	di->dev = &pdev->dev;
+	di->parent = dev_get_drvdata(pdev->dev.parent);
+	di->gpadc = ab5500_gpadc_get("ab5500-adc.0");
+
+	plat_data = pdev->dev.platform_data;
+	di->pdata = plat_data->fg;
+	di->bat = plat_data->battery;
+
+	/* get fg specific platform data */
+	if (!di->pdata) {
+		dev_err(di->dev, "no fg platform data supplied\n");
+		ret = -EINVAL;
+		goto free_device_info;
+	}
+
+	/* get battery specific platform data */
+	if (!di->bat) {
+		dev_err(di->dev, "no battery platform data supplied\n");
+		ret = -EINVAL;
+		goto free_device_info;
+	}
+
+	di->fg_psy.name = "ab5500_fg";
+	di->fg_psy.type = POWER_SUPPLY_TYPE_BATTERY;
+	di->fg_psy.properties = ab5500_fg_props;
+	di->fg_psy.num_properties = ARRAY_SIZE(ab5500_fg_props);
+	di->fg_psy.get_property = ab5500_fg_get_property;
+	di->fg_psy.supplied_to = di->pdata->supplied_to;
+	di->fg_psy.num_supplicants = di->pdata->num_supplicants;
+	di->fg_psy.external_power_changed = ab5500_fg_external_power_changed;
+
+	di->bat_cap.max_mah_design = MILLI_TO_MICRO *
+		di->bat->bat_type[di->bat->batt_id].charge_full_design;
+
+	di->bat_cap.max_mah = di->bat_cap.max_mah_design;
+
+	di->vbat_nom = di->bat->bat_type[di->bat->batt_id].nominal_voltage;
+
+	di->init_capacity = true;
+
+	ab5500_fg_charge_state_to(di, AB5500_FG_CHARGE_INIT);
+	ab5500_fg_discharge_state_to(di, AB5500_FG_DISCHARGE_INIT);
+
+	/* Create a work queue for running the FG algorithm */
+	di->fg_wq = create_singlethread_workqueue("ab5500_fg_wq");
+	if (di->fg_wq == NULL) {
+		dev_err(di->dev, "failed to create work queue\n");
+		goto free_device_info;
+	}
+
+	/* Init work for running the fg algorithm instantly */
+	INIT_WORK(&di->fg_work, ab5500_fg_instant_work);
+
+	/* Init work for getting the battery accumulated current */
+	INIT_DELAYED_WORK_DEFERRABLE(&di->fg_acc_cur_work,
+			ab5500_fg_acc_cur_work);
+
+	/* Work delayed Queue to run the state machine */
+	INIT_DELAYED_WORK_DEFERRABLE(&di->fg_periodic_work,
+		ab5500_fg_periodic_work);
+
+	/* Work to check low battery condition */
+	INIT_DELAYED_WORK_DEFERRABLE(&di->fg_low_bat_work,
+		ab5500_fg_low_bat_work);
+
+	list_add_tail(&di->node, &ab5500_fg_list);
+
+	/* Initialize OVV, and other registers */
+	ret = ab5500_fg_init_hw_registers(di);
+	if (ret) {
+		dev_err(di->dev, "failed to initialize registers\n");
+		goto free_fg_wq;
+	}
+
+	/* Consider battery unknown until we're informed otherwise */
+	di->flags.batt_unknown = true;
+
+	/* Register FG power supply class */
+	ret = power_supply_register(di->dev, &di->fg_psy);
+	if (ret) {
+		dev_err(di->dev, "failed to register FG psy\n");
+		goto free_fg_wq;
+	}
+
+	di->fg_samples = SEC_TO_SAMPLE(di->bat->fg_params->init_timer);
+	ab5500_fg_coulomb_counter(di, true);
+
+	/* Initilialize avg current timer */
+	init_timer(&di->avg_current_timer);
+	di->avg_current_timer.function = ab5500_fg_acc_cur_timer_expired;
+	di->avg_current_timer.data = (unsigned long) di;
+	di->avg_current_timer.expires = 60 * HZ;;
+	if (!timer_pending(&di->avg_current_timer))
+		add_timer(&di->avg_current_timer);
+	else
+		mod_timer(&di->avg_current_timer, 60 * HZ);
+
+	platform_set_drvdata(pdev, di);
+
+	/* Calibrate the fg first time */
+	di->flags.calibrate = true;
+	di->calib_state = AB5500_FG_CALIB_INIT;
+	/* Run the FG algorithm */
+	queue_delayed_work(di->fg_wq, &di->fg_periodic_work, 0);
+	queue_delayed_work(di->fg_wq, &di->fg_acc_cur_work, 0);
+
+	dev_info(di->dev, "probe success\n");
+	return ret;
+
+free_fg_wq:
+	destroy_workqueue(di->fg_wq);
+free_device_info:
+	kfree(di);
+
+	return ret;
+}
+
+static struct platform_driver ab5500_fg_driver = {
+	.probe = ab5500_fg_probe,
+	.remove = __devexit_p(ab5500_fg_remove),
+	.suspend = ab5500_fg_suspend,
+	.resume = ab5500_fg_resume,
+	.driver = {
+		.name = "ab5500-fg",
+		.owner = THIS_MODULE,
+	},
+};
+
+static int __init ab5500_fg_init(void)
+{
+	return platform_driver_register(&ab5500_fg_driver);
+}
+
+static void __exit ab5500_fg_exit(void)
+{
+	platform_driver_unregister(&ab5500_fg_driver);
+}
+
+subsys_initcall_sync(ab5500_fg_init);
+module_exit(ab5500_fg_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Johan Palsson, Karl Komierowski");
+MODULE_ALIAS("platform:ab5500-fg");
+MODULE_DESCRIPTION("AB5500 Fuel Gauge driver");