Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1172 insertions, 0 deletions

diff --git a/drivers/power/supply/ab8500_btemp.c b/drivers/power/supply/ab8500_btemp.c
new file mode 100644
index 000000000..5a1adceb6
--- /dev/null
+++ b/drivers/power/supply/ab8500_btemp.c
@@ -0,0 +1,1172 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) ST-Ericsson SA 2012
+ *
+ * Battery temperature driver for AB8500
+ *
+ * Author:
+ *	Johan Palsson <johan.palsson@stericsson.com>
+ *	Karl Komierowski <karl.komierowski@stericsson.com>
+ *	Arun R Murthy <arun.murthy@stericsson.com>
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/completion.h>
+#include <linux/workqueue.h>
+#include <linux/jiffies.h>
+#include <linux/of.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/abx500.h>
+#include <linux/mfd/abx500/ab8500.h>
+#include <linux/mfd/abx500/ab8500-bm.h>
+#include <linux/iio/consumer.h>
+
+#define VTVOUT_V			1800
+
+#define BTEMP_THERMAL_LOW_LIMIT		-10
+#define BTEMP_THERMAL_MED_LIMIT		0
+#define BTEMP_THERMAL_HIGH_LIMIT_52	52
+#define BTEMP_THERMAL_HIGH_LIMIT_57	57
+#define BTEMP_THERMAL_HIGH_LIMIT_62	62
+
+#define BTEMP_BATCTRL_CURR_SRC_7UA	7
+#define BTEMP_BATCTRL_CURR_SRC_20UA	20
+
+#define BTEMP_BATCTRL_CURR_SRC_16UA	16
+#define BTEMP_BATCTRL_CURR_SRC_18UA	18
+
+#define BTEMP_BATCTRL_CURR_SRC_60UA	60
+#define BTEMP_BATCTRL_CURR_SRC_120UA	120
+
+/**
+ * struct ab8500_btemp_interrupts - ab8500 interrupts
+ * @name:	name of the interrupt
+ * @isr		function pointer to the isr
+ */
+struct ab8500_btemp_interrupts {
+	char *name;
+	irqreturn_t (*isr)(int irq, void *data);
+};
+
+struct ab8500_btemp_events {
+	bool batt_rem;
+	bool btemp_high;
+	bool btemp_medhigh;
+	bool btemp_lowmed;
+	bool btemp_low;
+	bool ac_conn;
+	bool usb_conn;
+};
+
+struct ab8500_btemp_ranges {
+	int btemp_high_limit;
+	int btemp_med_limit;
+	int btemp_low_limit;
+};
+
+/**
+ * struct ab8500_btemp - ab8500 BTEMP device information
+ * @dev:		Pointer to the structure device
+ * @node:		List of AB8500 BTEMPs, hence prepared for reentrance
+ * @curr_source:	What current source we use, in uA
+ * @bat_temp:		Dispatched battery temperature in degree Celsius
+ * @prev_bat_temp	Last measured battery temperature in degree Celsius
+ * @parent:		Pointer to the struct ab8500
+ * @adc_btemp_ball:	ADC channel for the battery ball temperature
+ * @adc_bat_ctrl:	ADC channel for the battery control
+ * @fg:			Pointer to the struct fg
+ * @bm:           	Platform specific battery management information
+ * @btemp_psy:		Structure for BTEMP specific battery properties
+ * @events:		Structure for information about events triggered
+ * @btemp_ranges:	Battery temperature range structure
+ * @btemp_wq:		Work queue for measuring the temperature periodically
+ * @btemp_periodic_work:	Work for measuring the temperature periodically
+ * @initialized:	True if battery id read.
+ */
+struct ab8500_btemp {
+	struct device *dev;
+	struct list_head node;
+	int curr_source;
+	int bat_temp;
+	int prev_bat_temp;
+	struct ab8500 *parent;
+	struct iio_channel *btemp_ball;
+	struct iio_channel *bat_ctrl;
+	struct ab8500_fg *fg;
+	struct abx500_bm_data *bm;
+	struct power_supply *btemp_psy;
+	struct ab8500_btemp_events events;
+	struct ab8500_btemp_ranges btemp_ranges;
+	struct workqueue_struct *btemp_wq;
+	struct delayed_work btemp_periodic_work;
+	bool initialized;
+};
+
+/* BTEMP power supply properties */
+static enum power_supply_property ab8500_btemp_props[] = {
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_ONLINE,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_TEMP,
+};
+
+static LIST_HEAD(ab8500_btemp_list);
+
+/**
+ * ab8500_btemp_get() - returns a reference to the primary AB8500 BTEMP
+ * (i.e. the first BTEMP in the instance list)
+ */
+struct ab8500_btemp *ab8500_btemp_get(void)
+{
+	return list_first_entry(&ab8500_btemp_list, struct ab8500_btemp, node);
+}
+EXPORT_SYMBOL(ab8500_btemp_get);
+
+/**
+ * ab8500_btemp_batctrl_volt_to_res() - convert batctrl voltage to resistance
+ * @di:		pointer to the ab8500_btemp structure
+ * @v_batctrl:	measured batctrl voltage
+ * @inst_curr:	measured instant current
+ *
+ * This function returns the battery resistance that is
+ * derived from the BATCTRL voltage.
+ * Returns value in Ohms.
+ */
+static int ab8500_btemp_batctrl_volt_to_res(struct ab8500_btemp *di,
+	int v_batctrl, int inst_curr)
+{
+	int rbs;
+
+	if (is_ab8500_1p1_or_earlier(di->parent)) {
+		/*
+		 * For ABB cut1.0 and 1.1 BAT_CTRL is internally
+		 * connected to 1.8V through a 450k resistor
+		 */
+		return (450000 * (v_batctrl)) / (1800 - v_batctrl);
+	}
+
+	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL) {
+		/*
+		 * If the battery has internal NTC, we use the current
+		 * source to calculate the resistance.
+		 */
+		rbs = (v_batctrl * 1000
+		       - di->bm->gnd_lift_resistance * inst_curr)
+		      / di->curr_source;
+	} else {
+		/*
+		 * BAT_CTRL is internally
+		 * connected to 1.8V through a 80k resistor
+		 */
+		rbs = (80000 * (v_batctrl)) / (1800 - v_batctrl);
+	}
+
+	return rbs;
+}
+
+/**
+ * ab8500_btemp_read_batctrl_voltage() - measure batctrl voltage
+ * @di:		pointer to the ab8500_btemp structure
+ *
+ * This function returns the voltage on BATCTRL. Returns value in mV.
+ */
+static int ab8500_btemp_read_batctrl_voltage(struct ab8500_btemp *di)
+{
+	int vbtemp, ret;
+	static int prev;
+
+	ret = iio_read_channel_processed(di->bat_ctrl, &vbtemp);
+	if (ret < 0) {
+		dev_err(di->dev,
+			"%s ADC conversion failed, using previous value",
+			__func__);
+		return prev;
+	}
+	prev = vbtemp;
+	return vbtemp;
+}
+
+/**
+ * ab8500_btemp_curr_source_enable() - enable/disable batctrl current source
+ * @di:		pointer to the ab8500_btemp structure
+ * @enable:	enable or disable the current source
+ *
+ * Enable or disable the current sources for the BatCtrl AD channel
+ */
+static int ab8500_btemp_curr_source_enable(struct ab8500_btemp *di,
+	bool enable)
+{
+	int curr;
+	int ret = 0;
+
+	/*
+	 * BATCTRL current sources are included on AB8500 cut2.0
+	 * and future versions
+	 */
+	if (is_ab8500_1p1_or_earlier(di->parent))
+		return 0;
+
+	/* Only do this for batteries with internal NTC */
+	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL && enable) {
+
+		if (di->curr_source == BTEMP_BATCTRL_CURR_SRC_7UA)
+			curr = BAT_CTRL_7U_ENA;
+		else
+			curr = BAT_CTRL_20U_ENA;
+
+		dev_dbg(di->dev, "Set BATCTRL %duA\n", di->curr_source);
+
+		ret = abx500_mask_and_set_register_interruptible(di->dev,
+			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
+			FORCE_BAT_CTRL_CMP_HIGH, FORCE_BAT_CTRL_CMP_HIGH);
+		if (ret) {
+			dev_err(di->dev, "%s failed setting cmp_force\n",
+				__func__);
+			return ret;
+		}
+
+		/*
+		 * We have to wait one 32kHz cycle before enabling
+		 * the current source, since ForceBatCtrlCmpHigh needs
+		 * to be written in a separate cycle
+		 */
+		udelay(32);
+
+		ret = abx500_set_register_interruptible(di->dev,
+			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
+			FORCE_BAT_CTRL_CMP_HIGH | curr);
+		if (ret) {
+			dev_err(di->dev, "%s failed enabling current source\n",
+				__func__);
+			goto disable_curr_source;
+		}
+	} else if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL && !enable) {
+		dev_dbg(di->dev, "Disable BATCTRL curr source\n");
+
+		/* Write 0 to the curr bits */
+		ret = abx500_mask_and_set_register_interruptible(
+			di->dev,
+			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
+			BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA,
+			~(BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA));
+
+		if (ret) {
+			dev_err(di->dev, "%s failed disabling current source\n",
+				__func__);
+			goto disable_curr_source;
+		}
+
+		/* Enable Pull-Up and comparator */
+		ret = abx500_mask_and_set_register_interruptible(di->dev,
+			AB8500_CHARGER,	AB8500_BAT_CTRL_CURRENT_SOURCE,
+			BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA,
+			BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA);
+		if (ret) {
+			dev_err(di->dev, "%s failed enabling PU and comp\n",
+				__func__);
+			goto enable_pu_comp;
+		}
+
+		/*
+		 * We have to wait one 32kHz cycle before disabling
+		 * ForceBatCtrlCmpHigh since this needs to be written
+		 * in a separate cycle
+		 */
+		udelay(32);
+
+		/* Disable 'force comparator' */
+		ret = abx500_mask_and_set_register_interruptible(di->dev,
+			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
+			FORCE_BAT_CTRL_CMP_HIGH, ~FORCE_BAT_CTRL_CMP_HIGH);
+		if (ret) {
+			dev_err(di->dev, "%s failed disabling force comp\n",
+				__func__);
+			goto disable_force_comp;
+		}
+	}
+	return ret;
+
+	/*
+	 * We have to try unsetting FORCE_BAT_CTRL_CMP_HIGH one more time
+	 * if we got an error above
+	 */
+disable_curr_source:
+	/* Write 0 to the curr bits */
+	ret = abx500_mask_and_set_register_interruptible(di->dev,
+		AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
+		BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA,
+		~(BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA));
+
+	if (ret) {
+		dev_err(di->dev, "%s failed disabling current source\n",
+			__func__);
+		return ret;
+	}
+enable_pu_comp:
+	/* Enable Pull-Up and comparator */
+	ret = abx500_mask_and_set_register_interruptible(di->dev,
+		AB8500_CHARGER,	AB8500_BAT_CTRL_CURRENT_SOURCE,
+		BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA,
+		BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA);
+	if (ret) {
+		dev_err(di->dev, "%s failed enabling PU and comp\n",
+			__func__);
+		return ret;
+	}
+
+disable_force_comp:
+	/*
+	 * We have to wait one 32kHz cycle before disabling
+	 * ForceBatCtrlCmpHigh since this needs to be written
+	 * in a separate cycle
+	 */
+	udelay(32);
+
+	/* Disable 'force comparator' */
+	ret = abx500_mask_and_set_register_interruptible(di->dev,
+		AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
+		FORCE_BAT_CTRL_CMP_HIGH, ~FORCE_BAT_CTRL_CMP_HIGH);
+	if (ret) {
+		dev_err(di->dev, "%s failed disabling force comp\n",
+			__func__);
+		return ret;
+	}
+
+	return ret;
+}
+
+/**
+ * ab8500_btemp_get_batctrl_res() - get battery resistance
+ * @di:		pointer to the ab8500_btemp structure
+ *
+ * This function returns the battery pack identification resistance.
+ * Returns value in Ohms.
+ */
+static int ab8500_btemp_get_batctrl_res(struct ab8500_btemp *di)
+{
+	int ret;
+	int batctrl = 0;
+	int res;
+	int inst_curr;
+	int i;
+
+	/*
+	 * BATCTRL current sources are included on AB8500 cut2.0
+	 * and future versions
+	 */
+	ret = ab8500_btemp_curr_source_enable(di, true);
+	if (ret) {
+		dev_err(di->dev, "%s curr source enabled failed\n", __func__);
+		return ret;
+	}
+
+	if (!di->fg)
+		di->fg = ab8500_fg_get();
+	if (!di->fg) {
+		dev_err(di->dev, "No fg found\n");
+		return -EINVAL;
+	}
+
+	ret = ab8500_fg_inst_curr_start(di->fg);
+
+	if (ret) {
+		dev_err(di->dev, "Failed to start current measurement\n");
+		return ret;
+	}
+
+	do {
+		msleep(20);
+	} while (!ab8500_fg_inst_curr_started(di->fg));
+
+	i = 0;
+
+	do {
+		batctrl += ab8500_btemp_read_batctrl_voltage(di);
+		i++;
+		msleep(20);
+	} while (!ab8500_fg_inst_curr_done(di->fg));
+	batctrl /= i;
+
+	ret = ab8500_fg_inst_curr_finalize(di->fg, &inst_curr);
+	if (ret) {
+		dev_err(di->dev, "Failed to finalize current measurement\n");
+		return ret;
+	}
+
+	res = ab8500_btemp_batctrl_volt_to_res(di, batctrl, inst_curr);
+
+	ret = ab8500_btemp_curr_source_enable(di, false);
+	if (ret) {
+		dev_err(di->dev, "%s curr source disable failed\n", __func__);
+		return ret;
+	}
+
+	dev_dbg(di->dev, "%s batctrl: %d res: %d inst_curr: %d samples: %d\n",
+		__func__, batctrl, res, inst_curr, i);
+
+	return res;
+}
+
+/**
+ * ab8500_btemp_res_to_temp() - resistance to temperature
+ * @di:		pointer to the ab8500_btemp structure
+ * @tbl:	pointer to the resiatance to temperature table
+ * @tbl_size:	size of the resistance to temperature table
+ * @res:	resistance to calculate the temperature from
+ *
+ * This function returns the battery temperature in degrees Celsius
+ * based on the NTC resistance.
+ */
+static int ab8500_btemp_res_to_temp(struct ab8500_btemp *di,
+	const struct abx500_res_to_temp *tbl, int tbl_size, int res)
+{
+	int i;
+	/*
+	 * Calculate the formula for the straight line
+	 * Simple interpolation if we are within
+	 * the resistance table limits, extrapolate
+	 * if resistance is outside the limits.
+	 */
+	if (res > tbl[0].resist)
+		i = 0;
+	else if (res <= tbl[tbl_size - 1].resist)
+		i = tbl_size - 2;
+	else {
+		i = 0;
+		while (!(res <= tbl[i].resist &&
+			res > tbl[i + 1].resist))
+			i++;
+	}
+
+	return tbl[i].temp + ((tbl[i + 1].temp - tbl[i].temp) *
+		(res - tbl[i].resist)) / (tbl[i + 1].resist - tbl[i].resist);
+}
+
+/**
+ * ab8500_btemp_measure_temp() - measure battery temperature
+ * @di:		pointer to the ab8500_btemp structure
+ *
+ * Returns battery temperature (on success) else the previous temperature
+ */
+static int ab8500_btemp_measure_temp(struct ab8500_btemp *di)
+{
+	int temp, ret;
+	static int prev;
+	int rbat, rntc, vntc;
+	u8 id;
+
+	id = di->bm->batt_id;
+
+	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL &&
+			id != BATTERY_UNKNOWN) {
+
+		rbat = ab8500_btemp_get_batctrl_res(di);
+		if (rbat < 0) {
+			dev_err(di->dev, "%s get batctrl res failed\n",
+				__func__);
+			/*
+			 * Return out-of-range temperature so that
+			 * charging is stopped
+			 */
+			return BTEMP_THERMAL_LOW_LIMIT;
+		}
+
+		temp = ab8500_btemp_res_to_temp(di,
+			di->bm->bat_type[id].r_to_t_tbl,
+			di->bm->bat_type[id].n_temp_tbl_elements, rbat);
+	} else {
+		ret = iio_read_channel_processed(di->btemp_ball, &vntc);
+		if (ret < 0) {
+			dev_err(di->dev,
+				"%s ADC conversion failed,"
+				" using previous value\n", __func__);
+			return prev;
+		}
+		/*
+		 * The PCB NTC is sourced from VTVOUT via a 230kOhm
+		 * resistor.
+		 */
+		rntc = 230000 * vntc / (VTVOUT_V - vntc);
+
+		temp = ab8500_btemp_res_to_temp(di,
+			di->bm->bat_type[id].r_to_t_tbl,
+			di->bm->bat_type[id].n_temp_tbl_elements, rntc);
+		prev = temp;
+	}
+	dev_dbg(di->dev, "Battery temperature is %d\n", temp);
+	return temp;
+}
+
+/**
+ * ab8500_btemp_id() - Identify the connected battery
+ * @di:		pointer to the ab8500_btemp structure
+ *
+ * This function will try to identify the battery by reading the ID
+ * resistor. Some brands use a combined ID resistor with a NTC resistor to
+ * both be able to identify and to read the temperature of it.
+ */
+static int ab8500_btemp_id(struct ab8500_btemp *di)
+{
+	int res;
+	u8 i;
+
+	di->curr_source = BTEMP_BATCTRL_CURR_SRC_7UA;
+	di->bm->batt_id = BATTERY_UNKNOWN;
+
+	res =  ab8500_btemp_get_batctrl_res(di);
+	if (res < 0) {
+		dev_err(di->dev, "%s get batctrl res failed\n", __func__);
+		return -ENXIO;
+	}
+
+	/* BATTERY_UNKNOWN is defined on position 0, skip it! */
+	for (i = BATTERY_UNKNOWN + 1; i < di->bm->n_btypes; i++) {
+		if ((res <= di->bm->bat_type[i].resis_high) &&
+			(res >= di->bm->bat_type[i].resis_low)) {
+			dev_dbg(di->dev, "Battery detected on %s"
+				" low %d < res %d < high: %d"
+				" index: %d\n",
+				di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL ?
+				"BATCTRL" : "BATTEMP",
+				di->bm->bat_type[i].resis_low, res,
+				di->bm->bat_type[i].resis_high, i);
+
+			di->bm->batt_id = i;
+			break;
+		}
+	}
+
+	if (di->bm->batt_id == BATTERY_UNKNOWN) {
+		dev_warn(di->dev, "Battery identified as unknown"
+			", resistance %d Ohm\n", res);
+		return -ENXIO;
+	}
+
+	/*
+	 * We only have to change current source if the
+	 * detected type is Type 1.
+	 */
+	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL &&
+	    di->bm->batt_id == 1) {
+		dev_dbg(di->dev, "Set BATCTRL current source to 20uA\n");
+		di->curr_source = BTEMP_BATCTRL_CURR_SRC_20UA;
+	}
+
+	return di->bm->batt_id;
+}
+
+/**
+ * ab8500_btemp_periodic_work() - Measuring the temperature periodically
+ * @work:	pointer to the work_struct structure
+ *
+ * Work function for measuring the temperature periodically
+ */
+static void ab8500_btemp_periodic_work(struct work_struct *work)
+{
+	int interval;
+	int bat_temp;
+	struct ab8500_btemp *di = container_of(work,
+		struct ab8500_btemp, btemp_periodic_work.work);
+
+	if (!di->initialized) {
+		/* Identify the battery */
+		if (ab8500_btemp_id(di) < 0)
+			dev_warn(di->dev, "failed to identify the battery\n");
+	}
+
+	bat_temp = ab8500_btemp_measure_temp(di);
+	/*
+	 * Filter battery temperature.
+	 * Allow direct updates on temperature only if two samples result in
+	 * same temperature. Else only allow 1 degree change from previous
+	 * reported value in the direction of the new measurement.
+	 */
+	if ((bat_temp == di->prev_bat_temp) || !di->initialized) {
+		if ((di->bat_temp != di->prev_bat_temp) || !di->initialized) {
+			di->initialized = true;
+			di->bat_temp = bat_temp;
+			power_supply_changed(di->btemp_psy);
+		}
+	} else if (bat_temp < di->prev_bat_temp) {
+		di->bat_temp--;
+		power_supply_changed(di->btemp_psy);
+	} else if (bat_temp > di->prev_bat_temp) {
+		di->bat_temp++;
+		power_supply_changed(di->btemp_psy);
+	}
+	di->prev_bat_temp = bat_temp;
+
+	if (di->events.ac_conn || di->events.usb_conn)
+		interval = di->bm->temp_interval_chg;
+	else
+		interval = di->bm->temp_interval_nochg;
+
+	/* Schedule a new measurement */
+	queue_delayed_work(di->btemp_wq,
+		&di->btemp_periodic_work,
+		round_jiffies(interval * HZ));
+}
+
+/**
+ * ab8500_btemp_batctrlindb_handler() - battery removal detected
+ * @irq:       interrupt number
+ * @_di:       void pointer that has to address of ab8500_btemp
+ *
+ * Returns IRQ status(IRQ_HANDLED)
+ */
+static irqreturn_t ab8500_btemp_batctrlindb_handler(int irq, void *_di)
+{
+	struct ab8500_btemp *di = _di;
+	dev_err(di->dev, "Battery removal detected!\n");
+
+	di->events.batt_rem = true;
+	power_supply_changed(di->btemp_psy);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * ab8500_btemp_templow_handler() - battery temp lower than 10 degrees
+ * @irq:       interrupt number
+ * @_di:       void pointer that has to address of ab8500_btemp
+ *
+ * Returns IRQ status(IRQ_HANDLED)
+ */
+static irqreturn_t ab8500_btemp_templow_handler(int irq, void *_di)
+{
+	struct ab8500_btemp *di = _di;
+
+	if (is_ab8500_3p3_or_earlier(di->parent)) {
+		dev_dbg(di->dev, "Ignore false btemp low irq"
+			" for ABB cut 1.0, 1.1, 2.0 and 3.3\n");
+	} else {
+		dev_crit(di->dev, "Battery temperature lower than -10deg c\n");
+
+		di->events.btemp_low = true;
+		di->events.btemp_high = false;
+		di->events.btemp_medhigh = false;
+		di->events.btemp_lowmed = false;
+		power_supply_changed(di->btemp_psy);
+	}
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * ab8500_btemp_temphigh_handler() - battery temp higher than max temp
+ * @irq:       interrupt number
+ * @_di:       void pointer that has to address of ab8500_btemp
+ *
+ * Returns IRQ status(IRQ_HANDLED)
+ */
+static irqreturn_t ab8500_btemp_temphigh_handler(int irq, void *_di)
+{
+	struct ab8500_btemp *di = _di;
+
+	dev_crit(di->dev, "Battery temperature is higher than MAX temp\n");
+
+	di->events.btemp_high = true;
+	di->events.btemp_medhigh = false;
+	di->events.btemp_lowmed = false;
+	di->events.btemp_low = false;
+	power_supply_changed(di->btemp_psy);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * ab8500_btemp_lowmed_handler() - battery temp between low and medium
+ * @irq:       interrupt number
+ * @_di:       void pointer that has to address of ab8500_btemp
+ *
+ * Returns IRQ status(IRQ_HANDLED)
+ */
+static irqreturn_t ab8500_btemp_lowmed_handler(int irq, void *_di)
+{
+	struct ab8500_btemp *di = _di;
+
+	dev_dbg(di->dev, "Battery temperature is between low and medium\n");
+
+	di->events.btemp_lowmed = true;
+	di->events.btemp_medhigh = false;
+	di->events.btemp_high = false;
+	di->events.btemp_low = false;
+	power_supply_changed(di->btemp_psy);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * ab8500_btemp_medhigh_handler() - battery temp between medium and high
+ * @irq:       interrupt number
+ * @_di:       void pointer that has to address of ab8500_btemp
+ *
+ * Returns IRQ status(IRQ_HANDLED)
+ */
+static irqreturn_t ab8500_btemp_medhigh_handler(int irq, void *_di)
+{
+	struct ab8500_btemp *di = _di;
+
+	dev_dbg(di->dev, "Battery temperature is between medium and high\n");
+
+	di->events.btemp_medhigh = true;
+	di->events.btemp_lowmed = false;
+	di->events.btemp_high = false;
+	di->events.btemp_low = false;
+	power_supply_changed(di->btemp_psy);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * ab8500_btemp_periodic() - Periodic temperature measurements
+ * @di:		pointer to the ab8500_btemp structure
+ * @enable:	enable or disable periodic temperature measurements
+ *
+ * Starts of stops periodic temperature measurements. Periodic measurements
+ * should only be done when a charger is connected.
+ */
+static void ab8500_btemp_periodic(struct ab8500_btemp *di,
+	bool enable)
+{
+	dev_dbg(di->dev, "Enable periodic temperature measurements: %d\n",
+		enable);
+	/*
+	 * Make sure a new measurement is done directly by cancelling
+	 * any pending work
+	 */
+	cancel_delayed_work_sync(&di->btemp_periodic_work);
+
+	if (enable)
+		queue_delayed_work(di->btemp_wq, &di->btemp_periodic_work, 0);
+}
+
+/**
+ * ab8500_btemp_get_temp() - get battery temperature
+ * @di:		pointer to the ab8500_btemp structure
+ *
+ * Returns battery temperature
+ */
+int ab8500_btemp_get_temp(struct ab8500_btemp *di)
+{
+	int temp = 0;
+
+	/*
+	 * The BTEMP events are not reliabe on AB8500 cut3.3
+	 * and prior versions
+	 */
+	if (is_ab8500_3p3_or_earlier(di->parent)) {
+		temp = di->bat_temp * 10;
+	} else {
+		if (di->events.btemp_low) {
+			if (temp > di->btemp_ranges.btemp_low_limit)
+				temp = di->btemp_ranges.btemp_low_limit * 10;
+			else
+				temp = di->bat_temp * 10;
+		} else if (di->events.btemp_high) {
+			if (temp < di->btemp_ranges.btemp_high_limit)
+				temp = di->btemp_ranges.btemp_high_limit * 10;
+			else
+				temp = di->bat_temp * 10;
+		} else if (di->events.btemp_lowmed) {
+			if (temp > di->btemp_ranges.btemp_med_limit)
+				temp = di->btemp_ranges.btemp_med_limit * 10;
+			else
+				temp = di->bat_temp * 10;
+		} else if (di->events.btemp_medhigh) {
+			if (temp < di->btemp_ranges.btemp_med_limit)
+				temp = di->btemp_ranges.btemp_med_limit * 10;
+			else
+				temp = di->bat_temp * 10;
+		} else
+			temp = di->bat_temp * 10;
+	}
+	return temp;
+}
+EXPORT_SYMBOL(ab8500_btemp_get_temp);
+
+/**
+ * ab8500_btemp_get_batctrl_temp() - get the temperature
+ * @btemp:      pointer to the btemp structure
+ *
+ * Returns the batctrl temperature in millidegrees
+ */
+int ab8500_btemp_get_batctrl_temp(struct ab8500_btemp *btemp)
+{
+	return btemp->bat_temp * 1000;
+}
+EXPORT_SYMBOL(ab8500_btemp_get_batctrl_temp);
+
+/**
+ * ab8500_btemp_get_property() - get the btemp 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 btemp
+ * properties by reading the sysfs files.
+ * online:	presence of the battery
+ * present:	presence of the battery
+ * technology:	battery technology
+ * temp:	battery temperature
+ * Returns error code in case of failure else 0(on success)
+ */
+static int ab8500_btemp_get_property(struct power_supply *psy,
+	enum power_supply_property psp,
+	union power_supply_propval *val)
+{
+	struct ab8500_btemp *di = power_supply_get_drvdata(psy);
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_PRESENT:
+	case POWER_SUPPLY_PROP_ONLINE:
+		if (di->events.batt_rem)
+			val->intval = 0;
+		else
+			val->intval = 1;
+		break;
+	case POWER_SUPPLY_PROP_TECHNOLOGY:
+		val->intval = di->bm->bat_type[di->bm->batt_id].name;
+		break;
+	case POWER_SUPPLY_PROP_TEMP:
+		val->intval = ab8500_btemp_get_temp(di);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int ab8500_btemp_get_ext_psy_data(struct device *dev, void *data)
+{
+	struct power_supply *psy;
+	struct power_supply *ext = dev_get_drvdata(dev);
+	const char **supplicants = (const char **)ext->supplied_to;
+	struct ab8500_btemp *di;
+	union power_supply_propval ret;
+	int j;
+
+	psy = (struct power_supply *)data;
+	di = power_supply_get_drvdata(psy);
+
+	/*
+	 * For all psy where the name of your driver
+	 * appears in any supplied_to
+	 */
+	j = match_string(supplicants, ext->num_supplicants, psy->desc->name);
+	if (j < 0)
+		return 0;
+
+	/* Go through all properties for the psy */
+	for (j = 0; j < ext->desc->num_properties; j++) {
+		enum power_supply_property prop;
+		prop = ext->desc->properties[j];
+
+		if (power_supply_get_property(ext, prop, &ret))
+			continue;
+
+		switch (prop) {
+		case POWER_SUPPLY_PROP_PRESENT:
+			switch (ext->desc->type) {
+			case POWER_SUPPLY_TYPE_MAINS:
+				/* AC disconnected */
+				if (!ret.intval && di->events.ac_conn) {
+					di->events.ac_conn = false;
+				}
+				/* AC connected */
+				else if (ret.intval && !di->events.ac_conn) {
+					di->events.ac_conn = true;
+					if (!di->events.usb_conn)
+						ab8500_btemp_periodic(di, true);
+				}
+				break;
+			case POWER_SUPPLY_TYPE_USB:
+				/* USB disconnected */
+				if (!ret.intval && di->events.usb_conn) {
+					di->events.usb_conn = false;
+				}
+				/* USB connected */
+				else if (ret.intval && !di->events.usb_conn) {
+					di->events.usb_conn = true;
+					if (!di->events.ac_conn)
+						ab8500_btemp_periodic(di, true);
+				}
+				break;
+			default:
+				break;
+			}
+			break;
+		default:
+			break;
+		}
+	}
+	return 0;
+}
+
+/**
+ * ab8500_btemp_external_power_changed() - callback for power supply changes
+ * @psy:       pointer to the structure power_supply
+ *
+ * This function is pointing to the function pointer external_power_changed
+ * of the structure power_supply.
+ * This function gets executed when there is a change in the external power
+ * supply to the btemp.
+ */
+static void ab8500_btemp_external_power_changed(struct power_supply *psy)
+{
+	class_for_each_device(power_supply_class, NULL, psy,
+			      ab8500_btemp_get_ext_psy_data);
+}
+
+/* ab8500 btemp driver interrupts and their respective isr */
+static struct ab8500_btemp_interrupts ab8500_btemp_irq[] = {
+	{"BAT_CTRL_INDB", ab8500_btemp_batctrlindb_handler},
+	{"BTEMP_LOW", ab8500_btemp_templow_handler},
+	{"BTEMP_HIGH", ab8500_btemp_temphigh_handler},
+	{"BTEMP_LOW_MEDIUM", ab8500_btemp_lowmed_handler},
+	{"BTEMP_MEDIUM_HIGH", ab8500_btemp_medhigh_handler},
+};
+
+#if defined(CONFIG_PM)
+static int ab8500_btemp_resume(struct platform_device *pdev)
+{
+	struct ab8500_btemp *di = platform_get_drvdata(pdev);
+
+	ab8500_btemp_periodic(di, true);
+
+	return 0;
+}
+
+static int ab8500_btemp_suspend(struct platform_device *pdev,
+	pm_message_t state)
+{
+	struct ab8500_btemp *di = platform_get_drvdata(pdev);
+
+	ab8500_btemp_periodic(di, false);
+
+	return 0;
+}
+#else
+#define ab8500_btemp_suspend      NULL
+#define ab8500_btemp_resume       NULL
+#endif
+
+static int ab8500_btemp_remove(struct platform_device *pdev)
+{
+	struct ab8500_btemp *di = platform_get_drvdata(pdev);
+	int i, irq;
+
+	/* Disable interrupts */
+	for (i = 0; i < ARRAY_SIZE(ab8500_btemp_irq); i++) {
+		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
+		free_irq(irq, di);
+	}
+
+	/* Delete the work queue */
+	destroy_workqueue(di->btemp_wq);
+
+	flush_scheduled_work();
+	power_supply_unregister(di->btemp_psy);
+
+	return 0;
+}
+
+static char *supply_interface[] = {
+	"ab8500_chargalg",
+	"ab8500_fg",
+};
+
+static const struct power_supply_desc ab8500_btemp_desc = {
+	.name			= "ab8500_btemp",
+	.type			= POWER_SUPPLY_TYPE_BATTERY,
+	.properties		= ab8500_btemp_props,
+	.num_properties		= ARRAY_SIZE(ab8500_btemp_props),
+	.get_property		= ab8500_btemp_get_property,
+	.external_power_changed	= ab8500_btemp_external_power_changed,
+};
+
+static int ab8500_btemp_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct abx500_bm_data *plat = pdev->dev.platform_data;
+	struct power_supply_config psy_cfg = {};
+	struct ab8500_btemp *di;
+	int irq, i, ret = 0;
+	u8 val;
+
+	di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
+	if (!di) {
+		dev_err(&pdev->dev, "%s no mem for ab8500_btemp\n", __func__);
+		return -ENOMEM;
+	}
+
+	if (!plat) {
+		dev_err(&pdev->dev, "no battery management data supplied\n");
+		return -EINVAL;
+	}
+	di->bm = plat;
+
+	if (np) {
+		ret = ab8500_bm_of_probe(&pdev->dev, np, di->bm);
+		if (ret) {
+			dev_err(&pdev->dev, "failed to get battery information\n");
+			return ret;
+		}
+	}
+
+	/* get parent data */
+	di->dev = &pdev->dev;
+	di->parent = dev_get_drvdata(pdev->dev.parent);
+
+	/* Get ADC channels */
+	di->btemp_ball = devm_iio_channel_get(&pdev->dev, "btemp_ball");
+	if (IS_ERR(di->btemp_ball)) {
+		if (PTR_ERR(di->btemp_ball) == -ENODEV)
+			return -EPROBE_DEFER;
+		dev_err(&pdev->dev, "failed to get BTEMP BALL ADC channel\n");
+		return PTR_ERR(di->btemp_ball);
+	}
+	di->bat_ctrl = devm_iio_channel_get(&pdev->dev, "bat_ctrl");
+	if (IS_ERR(di->bat_ctrl)) {
+		if (PTR_ERR(di->bat_ctrl) == -ENODEV)
+			return -EPROBE_DEFER;
+		dev_err(&pdev->dev, "failed to get BAT CTRL ADC channel\n");
+		return PTR_ERR(di->bat_ctrl);
+	}
+
+	di->initialized = false;
+
+	psy_cfg.supplied_to = supply_interface;
+	psy_cfg.num_supplicants = ARRAY_SIZE(supply_interface);
+	psy_cfg.drv_data = di;
+
+	/* Create a work queue for the btemp */
+	di->btemp_wq =
+		alloc_workqueue("ab8500_btemp_wq", WQ_MEM_RECLAIM, 0);
+	if (di->btemp_wq == NULL) {
+		dev_err(di->dev, "failed to create work queue\n");
+		return -ENOMEM;
+	}
+
+	/* Init work for measuring temperature periodically */
+	INIT_DEFERRABLE_WORK(&di->btemp_periodic_work,
+		ab8500_btemp_periodic_work);
+
+	/* Set BTEMP thermal limits. Low and Med are fixed */
+	di->btemp_ranges.btemp_low_limit = BTEMP_THERMAL_LOW_LIMIT;
+	di->btemp_ranges.btemp_med_limit = BTEMP_THERMAL_MED_LIMIT;
+
+	ret = abx500_get_register_interruptible(di->dev, AB8500_CHARGER,
+		AB8500_BTEMP_HIGH_TH, &val);
+	if (ret < 0) {
+		dev_err(di->dev, "%s ab8500 read failed\n", __func__);
+		goto free_btemp_wq;
+	}
+	switch (val) {
+	case BTEMP_HIGH_TH_57_0:
+	case BTEMP_HIGH_TH_57_1:
+		di->btemp_ranges.btemp_high_limit =
+			BTEMP_THERMAL_HIGH_LIMIT_57;
+		break;
+	case BTEMP_HIGH_TH_52:
+		di->btemp_ranges.btemp_high_limit =
+			BTEMP_THERMAL_HIGH_LIMIT_52;
+		break;
+	case BTEMP_HIGH_TH_62:
+		di->btemp_ranges.btemp_high_limit =
+			BTEMP_THERMAL_HIGH_LIMIT_62;
+		break;
+	}
+
+	/* Register BTEMP power supply class */
+	di->btemp_psy = power_supply_register(di->dev, &ab8500_btemp_desc,
+					      &psy_cfg);
+	if (IS_ERR(di->btemp_psy)) {
+		dev_err(di->dev, "failed to register BTEMP psy\n");
+		ret = PTR_ERR(di->btemp_psy);
+		goto free_btemp_wq;
+	}
+
+	/* Register interrupts */
+	for (i = 0; i < ARRAY_SIZE(ab8500_btemp_irq); i++) {
+		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
+		if (irq < 0) {
+			ret = irq;
+			goto free_irq;
+		}
+
+		ret = request_threaded_irq(irq, NULL, ab8500_btemp_irq[i].isr,
+			IRQF_SHARED | IRQF_NO_SUSPEND,
+			ab8500_btemp_irq[i].name, di);
+
+		if (ret) {
+			dev_err(di->dev, "failed to request %s IRQ %d: %d\n"
+				, ab8500_btemp_irq[i].name, irq, ret);
+			goto free_irq;
+		}
+		dev_dbg(di->dev, "Requested %s IRQ %d: %d\n",
+			ab8500_btemp_irq[i].name, irq, ret);
+	}
+
+	platform_set_drvdata(pdev, di);
+
+	/* Kick off periodic temperature measurements */
+	ab8500_btemp_periodic(di, true);
+	list_add_tail(&di->node, &ab8500_btemp_list);
+
+	return ret;
+
+free_irq:
+	/* We also have to free all successfully registered irqs */
+	for (i = i - 1; i >= 0; i--) {
+		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
+		free_irq(irq, di);
+	}
+
+	power_supply_unregister(di->btemp_psy);
+free_btemp_wq:
+	destroy_workqueue(di->btemp_wq);
+	return ret;
+}
+
+static const struct of_device_id ab8500_btemp_match[] = {
+	{ .compatible = "stericsson,ab8500-btemp", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, ab8500_btemp_match);
+
+static struct platform_driver ab8500_btemp_driver = {
+	.probe = ab8500_btemp_probe,
+	.remove = ab8500_btemp_remove,
+	.suspend = ab8500_btemp_suspend,
+	.resume = ab8500_btemp_resume,
+	.driver = {
+		.name = "ab8500-btemp",
+		.of_match_table = ab8500_btemp_match,
+	},
+};
+
+static int __init ab8500_btemp_init(void)
+{
+	return platform_driver_register(&ab8500_btemp_driver);
+}
+
+static void __exit ab8500_btemp_exit(void)
+{
+	platform_driver_unregister(&ab8500_btemp_driver);
+}
+
+device_initcall(ab8500_btemp_init);
+module_exit(ab8500_btemp_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Johan Palsson, Karl Komierowski, Arun R Murthy");
+MODULE_ALIAS("platform:ab8500-btemp");
+MODULE_DESCRIPTION("AB8500 battery temperature driver");