Initial import

1 files changed, 1087 insertions, 0 deletions

diff --git a/drivers/mfd/ab8500-gpadc.c b/drivers/mfd/ab8500-gpadc.c
new file mode 100644
index 000000000..dabbc93ab
--- /dev/null
+++ b/drivers/mfd/ab8500-gpadc.c
@@ -0,0 +1,1087 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * License Terms: GNU General Public License v2
+ * Author: Arun R Murthy <arun.murthy@stericsson.com>
+ * Author: Daniel Willerud <daniel.willerud@stericsson.com>
+ * Author: Johan Palsson <johan.palsson@stericsson.com>
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/delay.h>
+#include <linux/pm_runtime.h>
+#include <linux/platform_device.h>
+#include <linux/completion.h>
+#include <linux/regulator/consumer.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/mfd/abx500.h>
+#include <linux/mfd/abx500/ab8500.h>
+#include <linux/mfd/abx500/ab8500-gpadc.h>
+
+/*
+ * GPADC register offsets
+ * Bank : 0x0A
+ */
+#define AB8500_GPADC_CTRL1_REG		0x00
+#define AB8500_GPADC_CTRL2_REG		0x01
+#define AB8500_GPADC_CTRL3_REG		0x02
+#define AB8500_GPADC_AUTO_TIMER_REG	0x03
+#define AB8500_GPADC_STAT_REG		0x04
+#define AB8500_GPADC_MANDATAL_REG	0x05
+#define AB8500_GPADC_MANDATAH_REG	0x06
+#define AB8500_GPADC_AUTODATAL_REG	0x07
+#define AB8500_GPADC_AUTODATAH_REG	0x08
+#define AB8500_GPADC_MUX_CTRL_REG	0x09
+#define AB8540_GPADC_MANDATA2L_REG	0x09
+#define AB8540_GPADC_MANDATA2H_REG	0x0A
+#define AB8540_GPADC_APEAAX_REG		0x10
+#define AB8540_GPADC_APEAAT_REG		0x11
+#define AB8540_GPADC_APEAAM_REG		0x12
+#define AB8540_GPADC_APEAAH_REG		0x13
+#define AB8540_GPADC_APEAAL_REG		0x14
+
+/*
+ * OTP register offsets
+ * Bank : 0x15
+ */
+#define AB8500_GPADC_CAL_1		0x0F
+#define AB8500_GPADC_CAL_2		0x10
+#define AB8500_GPADC_CAL_3		0x11
+#define AB8500_GPADC_CAL_4		0x12
+#define AB8500_GPADC_CAL_5		0x13
+#define AB8500_GPADC_CAL_6		0x14
+#define AB8500_GPADC_CAL_7		0x15
+/* New calibration for 8540 */
+#define AB8540_GPADC_OTP4_REG_7	0x38
+#define AB8540_GPADC_OTP4_REG_6	0x39
+#define AB8540_GPADC_OTP4_REG_5	0x3A
+
+/* gpadc constants */
+#define EN_VINTCORE12			0x04
+#define EN_VTVOUT			0x02
+#define EN_GPADC			0x01
+#define DIS_GPADC			0x00
+#define AVG_1				0x00
+#define AVG_4				0x20
+#define AVG_8				0x40
+#define AVG_16				0x60
+#define ADC_SW_CONV			0x04
+#define EN_ICHAR			0x80
+#define BTEMP_PULL_UP			0x08
+#define EN_BUF				0x40
+#define DIS_ZERO			0x00
+#define GPADC_BUSY			0x01
+#define EN_FALLING			0x10
+#define EN_TRIG_EDGE			0x02
+#define EN_VBIAS_XTAL_TEMP		0x02
+
+/* GPADC constants from AB8500 spec, UM0836 */
+#define ADC_RESOLUTION			1024
+#define ADC_CH_BTEMP_MIN		0
+#define ADC_CH_BTEMP_MAX		1350
+#define ADC_CH_DIETEMP_MIN		0
+#define ADC_CH_DIETEMP_MAX		1350
+#define ADC_CH_CHG_V_MIN		0
+#define ADC_CH_CHG_V_MAX		20030
+#define ADC_CH_ACCDET2_MIN		0
+#define ADC_CH_ACCDET2_MAX		2500
+#define ADC_CH_VBAT_MIN			2300
+#define ADC_CH_VBAT_MAX			4800
+#define ADC_CH_CHG_I_MIN		0
+#define ADC_CH_CHG_I_MAX		1500
+#define ADC_CH_BKBAT_MIN		0
+#define ADC_CH_BKBAT_MAX		3200
+
+/* GPADC constants from AB8540 spec */
+#define ADC_CH_IBAT_MIN			(-6000) /* mA range measured by ADC for ibat*/
+#define ADC_CH_IBAT_MAX			6000
+#define ADC_CH_IBAT_MIN_V		(-60)	/* mV range measured by ADC for ibat*/
+#define ADC_CH_IBAT_MAX_V		60
+#define IBAT_VDROP_L			(-56)  /* mV */
+#define IBAT_VDROP_H			56
+
+/* This is used to not lose precision when dividing to get gain and offset */
+#define CALIB_SCALE		1000
+/*
+ * Number of bits shift used to not lose precision
+ * when dividing to get ibat gain.
+ */
+#define CALIB_SHIFT_IBAT	20
+
+/* Time in ms before disabling regulator */
+#define GPADC_AUDOSUSPEND_DELAY		1
+
+#define CONVERSION_TIME			500 /* ms */
+
+enum cal_channels {
+	ADC_INPUT_VMAIN = 0,
+	ADC_INPUT_BTEMP,
+	ADC_INPUT_VBAT,
+	ADC_INPUT_IBAT,
+	NBR_CAL_INPUTS,
+};
+
+/**
+ * struct adc_cal_data - Table for storing gain and offset for the calibrated
+ * ADC channels
+ * @gain:		Gain of the ADC channel
+ * @offset:		Offset of the ADC channel
+ */
+struct adc_cal_data {
+	s64 gain;
+	s64 offset;
+	u16 otp_calib_hi;
+	u16 otp_calib_lo;
+};
+
+/**
+ * struct ab8500_gpadc - AB8500 GPADC device information
+ * @dev:			pointer to the struct device
+ * @node:			a list of AB8500 GPADCs, hence prepared for
+				reentrance
+ * @parent:			pointer to the struct ab8500
+ * @ab8500_gpadc_complete:	pointer to the struct completion, to indicate
+ *				the completion of gpadc conversion
+ * @ab8500_gpadc_lock:		structure of type mutex
+ * @regu:			pointer to the struct regulator
+ * @irq_sw:			interrupt number that is used by gpadc for Sw
+ *				conversion
+ * @irq_hw:			interrupt number that is used by gpadc for Hw
+ *				conversion
+ * @cal_data			array of ADC calibration data structs
+ */
+struct ab8500_gpadc {
+	struct device *dev;
+	struct list_head node;
+	struct ab8500 *parent;
+	struct completion ab8500_gpadc_complete;
+	struct mutex ab8500_gpadc_lock;
+	struct regulator *regu;
+	int irq_sw;
+	int irq_hw;
+	struct adc_cal_data cal_data[NBR_CAL_INPUTS];
+};
+
+static LIST_HEAD(ab8500_gpadc_list);
+
+/**
+ * ab8500_gpadc_get() - returns a reference to the primary AB8500 GPADC
+ * (i.e. the first GPADC in the instance list)
+ */
+struct ab8500_gpadc *ab8500_gpadc_get(char *name)
+{
+	struct ab8500_gpadc *gpadc;
+
+	list_for_each_entry(gpadc, &ab8500_gpadc_list, node) {
+		if (!strcmp(name, dev_name(gpadc->dev)))
+		    return gpadc;
+	}
+
+	return ERR_PTR(-ENOENT);
+}
+EXPORT_SYMBOL(ab8500_gpadc_get);
+
+/**
+ * ab8500_gpadc_ad_to_voltage() - Convert a raw ADC value to a voltage
+ */
+int ab8500_gpadc_ad_to_voltage(struct ab8500_gpadc *gpadc, u8 channel,
+	int ad_value)
+{
+	int res;
+
+	switch (channel) {
+	case MAIN_CHARGER_V:
+		/* For some reason we don't have calibrated data */
+		if (!gpadc->cal_data[ADC_INPUT_VMAIN].gain) {
+			res = ADC_CH_CHG_V_MIN + (ADC_CH_CHG_V_MAX -
+				ADC_CH_CHG_V_MIN) * ad_value /
+				ADC_RESOLUTION;
+			break;
+		}
+		/* Here we can use the calibrated data */
+		res = (int) (ad_value * gpadc->cal_data[ADC_INPUT_VMAIN].gain +
+			gpadc->cal_data[ADC_INPUT_VMAIN].offset) / CALIB_SCALE;
+		break;
+
+	case XTAL_TEMP:
+	case BAT_CTRL:
+	case BTEMP_BALL:
+	case ACC_DETECT1:
+	case ADC_AUX1:
+	case ADC_AUX2:
+		/* For some reason we don't have calibrated data */
+		if (!gpadc->cal_data[ADC_INPUT_BTEMP].gain) {
+			res = ADC_CH_BTEMP_MIN + (ADC_CH_BTEMP_MAX -
+				ADC_CH_BTEMP_MIN) * ad_value /
+				ADC_RESOLUTION;
+			break;
+		}
+		/* Here we can use the calibrated data */
+		res = (int) (ad_value * gpadc->cal_data[ADC_INPUT_BTEMP].gain +
+			gpadc->cal_data[ADC_INPUT_BTEMP].offset) / CALIB_SCALE;
+		break;
+
+	case MAIN_BAT_V:
+	case VBAT_TRUE_MEAS:
+		/* For some reason we don't have calibrated data */
+		if (!gpadc->cal_data[ADC_INPUT_VBAT].gain) {
+			res = ADC_CH_VBAT_MIN + (ADC_CH_VBAT_MAX -
+				ADC_CH_VBAT_MIN) * ad_value /
+				ADC_RESOLUTION;
+			break;
+		}
+		/* Here we can use the calibrated data */
+		res = (int) (ad_value * gpadc->cal_data[ADC_INPUT_VBAT].gain +
+			gpadc->cal_data[ADC_INPUT_VBAT].offset) / CALIB_SCALE;
+		break;
+
+	case DIE_TEMP:
+		res = ADC_CH_DIETEMP_MIN +
+			(ADC_CH_DIETEMP_MAX - ADC_CH_DIETEMP_MIN) * ad_value /
+			ADC_RESOLUTION;
+		break;
+
+	case ACC_DETECT2:
+		res = ADC_CH_ACCDET2_MIN +
+			(ADC_CH_ACCDET2_MAX - ADC_CH_ACCDET2_MIN) * ad_value /
+			ADC_RESOLUTION;
+		break;
+
+	case VBUS_V:
+		res = ADC_CH_CHG_V_MIN +
+			(ADC_CH_CHG_V_MAX - ADC_CH_CHG_V_MIN) * ad_value /
+			ADC_RESOLUTION;
+		break;
+
+	case MAIN_CHARGER_C:
+	case USB_CHARGER_C:
+		res = ADC_CH_CHG_I_MIN +
+			(ADC_CH_CHG_I_MAX - ADC_CH_CHG_I_MIN) * ad_value /
+			ADC_RESOLUTION;
+		break;
+
+	case BK_BAT_V:
+		res = ADC_CH_BKBAT_MIN +
+			(ADC_CH_BKBAT_MAX - ADC_CH_BKBAT_MIN) * ad_value /
+			ADC_RESOLUTION;
+		break;
+
+	case IBAT_VIRTUAL_CHANNEL:
+		/* For some reason we don't have calibrated data */
+		if (!gpadc->cal_data[ADC_INPUT_IBAT].gain) {
+			res = ADC_CH_IBAT_MIN + (ADC_CH_IBAT_MAX -
+				ADC_CH_IBAT_MIN) * ad_value /
+				ADC_RESOLUTION;
+			break;
+		}
+		/* Here we can use the calibrated data */
+		res = (int) (ad_value * gpadc->cal_data[ADC_INPUT_IBAT].gain +
+				gpadc->cal_data[ADC_INPUT_IBAT].offset)
+				>> CALIB_SHIFT_IBAT;
+		break;
+
+	default:
+		dev_err(gpadc->dev,
+			"unknown channel, not possible to convert\n");
+		res = -EINVAL;
+		break;
+
+	}
+	return res;
+}
+EXPORT_SYMBOL(ab8500_gpadc_ad_to_voltage);
+
+/**
+ * ab8500_gpadc_sw_hw_convert() - gpadc conversion
+ * @channel:	analog channel to be converted to digital data
+ * @avg_sample:  number of ADC sample to average
+ * @trig_egde:  selected ADC trig edge
+ * @trig_timer: selected ADC trigger delay timer
+ * @conv_type: selected conversion type (HW or SW conversion)
+ *
+ * This function converts the selected analog i/p to digital
+ * data.
+ */
+int ab8500_gpadc_sw_hw_convert(struct ab8500_gpadc *gpadc, u8 channel,
+		u8 avg_sample, u8 trig_edge, u8 trig_timer, u8 conv_type)
+{
+	int ad_value;
+	int voltage;
+
+	ad_value = ab8500_gpadc_read_raw(gpadc, channel, avg_sample,
+			trig_edge, trig_timer, conv_type);
+/* On failure retry a second time */
+	if (ad_value < 0)
+		ad_value = ab8500_gpadc_read_raw(gpadc, channel, avg_sample,
+			trig_edge, trig_timer, conv_type);
+if (ad_value < 0) {
+		dev_err(gpadc->dev, "GPADC raw value failed ch: %d\n",
+				channel);
+		return ad_value;
+	}
+
+	voltage = ab8500_gpadc_ad_to_voltage(gpadc, channel, ad_value);
+	if (voltage < 0)
+		dev_err(gpadc->dev, "GPADC to voltage conversion failed ch:"
+			" %d AD: 0x%x\n", channel, ad_value);
+
+	return voltage;
+}
+EXPORT_SYMBOL(ab8500_gpadc_sw_hw_convert);
+
+/**
+ * ab8500_gpadc_read_raw() - gpadc read
+ * @channel:	analog channel to be read
+ * @avg_sample:  number of ADC sample to average
+ * @trig_edge:  selected trig edge
+ * @trig_timer: selected ADC trigger delay timer
+ * @conv_type: selected conversion type (HW or SW conversion)
+ *
+ * This function obtains the raw ADC value for an hardware conversion,
+ * this then needs to be converted by calling ab8500_gpadc_ad_to_voltage()
+ */
+int ab8500_gpadc_read_raw(struct ab8500_gpadc *gpadc, u8 channel,
+		u8 avg_sample, u8 trig_edge, u8 trig_timer, u8 conv_type)
+{
+	int raw_data;
+	raw_data = ab8500_gpadc_double_read_raw(gpadc, channel,
+			avg_sample, trig_edge, trig_timer, conv_type, NULL);
+	return raw_data;
+}
+
+int ab8500_gpadc_double_read_raw(struct ab8500_gpadc *gpadc, u8 channel,
+		u8 avg_sample, u8 trig_edge, u8 trig_timer, u8 conv_type,
+		int *ibat)
+{
+	int ret;
+	int looplimit = 0;
+	unsigned long completion_timeout;
+	u8 val, low_data, high_data, low_data2, high_data2;
+	u8 val_reg1 = 0;
+	unsigned int delay_min = 0;
+	unsigned int delay_max = 0;
+	u8 data_low_addr, data_high_addr;
+
+	if (!gpadc)
+		return -ENODEV;
+
+	/* check if convertion is supported */
+	if ((gpadc->irq_sw < 0) && (conv_type == ADC_SW))
+		return -ENOTSUPP;
+	if ((gpadc->irq_hw < 0) && (conv_type == ADC_HW))
+		return -ENOTSUPP;
+
+	mutex_lock(&gpadc->ab8500_gpadc_lock);
+	/* Enable VTVout LDO this is required for GPADC */
+	pm_runtime_get_sync(gpadc->dev);
+
+	/* Check if ADC is not busy, lock and proceed */
+	do {
+		ret = abx500_get_register_interruptible(gpadc->dev,
+			AB8500_GPADC, AB8500_GPADC_STAT_REG, &val);
+		if (ret < 0)
+			goto out;
+		if (!(val & GPADC_BUSY))
+			break;
+		msleep(10);
+	} while (++looplimit < 10);
+	if (looplimit >= 10 && (val & GPADC_BUSY)) {
+		dev_err(gpadc->dev, "gpadc_conversion: GPADC busy");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* Enable GPADC */
+	val_reg1 |= EN_GPADC;
+
+	/* Select the channel source and set average samples */
+	switch (avg_sample) {
+	case SAMPLE_1:
+		val = channel | AVG_1;
+		break;
+	case SAMPLE_4:
+		val = channel | AVG_4;
+		break;
+	case SAMPLE_8:
+		val = channel | AVG_8;
+		break;
+	default:
+		val = channel | AVG_16;
+		break;
+	}
+
+	if (conv_type == ADC_HW) {
+		ret = abx500_set_register_interruptible(gpadc->dev,
+				AB8500_GPADC, AB8500_GPADC_CTRL3_REG, val);
+		val_reg1 |= EN_TRIG_EDGE;
+		if (trig_edge)
+			val_reg1 |= EN_FALLING;
+	}
+	else
+		ret = abx500_set_register_interruptible(gpadc->dev,
+				AB8500_GPADC, AB8500_GPADC_CTRL2_REG, val);
+	if (ret < 0) {
+		dev_err(gpadc->dev,
+			"gpadc_conversion: set avg samples failed\n");
+		goto out;
+	}
+
+	/*
+	 * Enable ADC, buffering, select rising edge and enable ADC path
+	 * charging current sense if it needed, ABB 3.0 needs some special
+	 * treatment too.
+	 */
+	switch (channel) {
+	case MAIN_CHARGER_C:
+	case USB_CHARGER_C:
+		val_reg1 |= EN_BUF | EN_ICHAR;
+		break;
+	case BTEMP_BALL:
+		if (!is_ab8500_2p0_or_earlier(gpadc->parent)) {
+			val_reg1 |= EN_BUF | BTEMP_PULL_UP;
+			/*
+			* Delay might be needed for ABB8500 cut 3.0, if not,
+			* remove when hardware will be availible
+			*/
+			delay_min = 1000; /* Delay in micro seconds */
+			delay_max = 10000; /* large range to optimise sleep mode */
+			break;
+		}
+		/* Intentional fallthrough */
+	default:
+		val_reg1 |= EN_BUF;
+		break;
+	}
+
+	/* Write configuration to register */
+	ret = abx500_set_register_interruptible(gpadc->dev,
+		AB8500_GPADC, AB8500_GPADC_CTRL1_REG, val_reg1);
+	if (ret < 0) {
+		dev_err(gpadc->dev,
+			"gpadc_conversion: set Control register failed\n");
+		goto out;
+	}
+
+	if (delay_min != 0)
+		usleep_range(delay_min, delay_max);
+
+	if (conv_type == ADC_HW) {
+		/* Set trigger delay timer */
+		ret = abx500_set_register_interruptible(gpadc->dev,
+			AB8500_GPADC, AB8500_GPADC_AUTO_TIMER_REG, trig_timer);
+		if (ret < 0) {
+			dev_err(gpadc->dev,
+				"gpadc_conversion: trig timer failed\n");
+			goto out;
+		}
+		completion_timeout = 2 * HZ;
+		data_low_addr = AB8500_GPADC_AUTODATAL_REG;
+		data_high_addr = AB8500_GPADC_AUTODATAH_REG;
+	} else {
+		/* Start SW conversion */
+		ret = abx500_mask_and_set_register_interruptible(gpadc->dev,
+			AB8500_GPADC, AB8500_GPADC_CTRL1_REG,
+			ADC_SW_CONV, ADC_SW_CONV);
+		if (ret < 0) {
+			dev_err(gpadc->dev,
+				"gpadc_conversion: start s/w conv failed\n");
+			goto out;
+		}
+		completion_timeout = msecs_to_jiffies(CONVERSION_TIME);
+		data_low_addr = AB8500_GPADC_MANDATAL_REG;
+		data_high_addr = AB8500_GPADC_MANDATAH_REG;
+	}
+
+	/* wait for completion of conversion */
+	if (!wait_for_completion_timeout(&gpadc->ab8500_gpadc_complete,
+			completion_timeout)) {
+		dev_err(gpadc->dev,
+			"timeout didn't receive GPADC conv interrupt\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* Read the converted RAW data */
+	ret = abx500_get_register_interruptible(gpadc->dev,
+			AB8500_GPADC, data_low_addr, &low_data);
+	if (ret < 0) {
+		dev_err(gpadc->dev, "gpadc_conversion: read low data failed\n");
+		goto out;
+	}
+
+	ret = abx500_get_register_interruptible(gpadc->dev,
+		AB8500_GPADC, data_high_addr, &high_data);
+	if (ret < 0) {
+		dev_err(gpadc->dev, "gpadc_conversion: read high data failed\n");
+		goto out;
+	}
+
+	/* Check if double convertion is required */
+	if ((channel == BAT_CTRL_AND_IBAT) ||
+			(channel == VBAT_MEAS_AND_IBAT) ||
+			(channel == VBAT_TRUE_MEAS_AND_IBAT) ||
+			(channel == BAT_TEMP_AND_IBAT)) {
+
+		if (conv_type == ADC_HW) {
+			/* not supported */
+			ret = -ENOTSUPP;
+			dev_err(gpadc->dev,
+				"gpadc_conversion: only SW double conversion supported\n");
+			goto out;
+		} else {
+			/* Read the converted RAW data 2 */
+			ret = abx500_get_register_interruptible(gpadc->dev,
+				AB8500_GPADC, AB8540_GPADC_MANDATA2L_REG,
+				&low_data2);
+			if (ret < 0) {
+				dev_err(gpadc->dev,
+					"gpadc_conversion: read sw low data 2 failed\n");
+				goto out;
+			}
+
+			ret = abx500_get_register_interruptible(gpadc->dev,
+				AB8500_GPADC, AB8540_GPADC_MANDATA2H_REG,
+				&high_data2);
+			if (ret < 0) {
+				dev_err(gpadc->dev,
+					"gpadc_conversion: read sw high data 2 failed\n");
+				goto out;
+			}
+			if (ibat != NULL) {
+				*ibat = (high_data2 << 8) | low_data2;
+			} else {
+				dev_warn(gpadc->dev,
+					"gpadc_conversion: ibat not stored\n");
+			}
+
+		}
+	}
+
+	/* Disable GPADC */
+	ret = abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC,
+		AB8500_GPADC_CTRL1_REG, DIS_GPADC);
+	if (ret < 0) {
+		dev_err(gpadc->dev, "gpadc_conversion: disable gpadc failed\n");
+		goto out;
+	}
+
+	/* Disable VTVout LDO this is required for GPADC */
+	pm_runtime_mark_last_busy(gpadc->dev);
+	pm_runtime_put_autosuspend(gpadc->dev);
+
+	mutex_unlock(&gpadc->ab8500_gpadc_lock);
+
+	return (high_data << 8) | low_data;
+
+out:
+	/*
+	 * It has shown to be needed to turn off the GPADC if an error occurs,
+	 * otherwise we might have problem when waiting for the busy bit in the
+	 * GPADC status register to go low. In V1.1 there wait_for_completion
+	 * seems to timeout when waiting for an interrupt.. Not seen in V2.0
+	 */
+	(void) abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC,
+		AB8500_GPADC_CTRL1_REG, DIS_GPADC);
+	pm_runtime_put(gpadc->dev);
+	mutex_unlock(&gpadc->ab8500_gpadc_lock);
+	dev_err(gpadc->dev,
+		"gpadc_conversion: Failed to AD convert channel %d\n", channel);
+	return ret;
+}
+EXPORT_SYMBOL(ab8500_gpadc_read_raw);
+
+/**
+ * ab8500_bm_gpadcconvend_handler() - isr for gpadc conversion completion
+ * @irq:	irq number
+ * @data:	pointer to the data passed during request irq
+ *
+ * This is a interrupt service routine for gpadc conversion completion.
+ * Notifies the gpadc completion is completed and the converted raw value
+ * can be read from the registers.
+ * Returns IRQ status(IRQ_HANDLED)
+ */
+static irqreturn_t ab8500_bm_gpadcconvend_handler(int irq, void *_gpadc)
+{
+	struct ab8500_gpadc *gpadc = _gpadc;
+
+	complete(&gpadc->ab8500_gpadc_complete);
+
+	return IRQ_HANDLED;
+}
+
+static int otp_cal_regs[] = {
+	AB8500_GPADC_CAL_1,
+	AB8500_GPADC_CAL_2,
+	AB8500_GPADC_CAL_3,
+	AB8500_GPADC_CAL_4,
+	AB8500_GPADC_CAL_5,
+	AB8500_GPADC_CAL_6,
+	AB8500_GPADC_CAL_7,
+};
+
+static int otp4_cal_regs[] = {
+	AB8540_GPADC_OTP4_REG_7,
+	AB8540_GPADC_OTP4_REG_6,
+	AB8540_GPADC_OTP4_REG_5,
+};
+
+static void ab8500_gpadc_read_calibration_data(struct ab8500_gpadc *gpadc)
+{
+	int i;
+	int ret[ARRAY_SIZE(otp_cal_regs)];
+	u8 gpadc_cal[ARRAY_SIZE(otp_cal_regs)];
+	int ret_otp4[ARRAY_SIZE(otp4_cal_regs)];
+	u8 gpadc_otp4[ARRAY_SIZE(otp4_cal_regs)];
+	int vmain_high, vmain_low;
+	int btemp_high, btemp_low;
+	int vbat_high, vbat_low;
+	int ibat_high, ibat_low;
+	s64 V_gain, V_offset, V2A_gain, V2A_offset;
+	struct ab8500 *ab8500;
+
+	ab8500 = gpadc->parent;
+
+	/* First we read all OTP registers and store the error code */
+	for (i = 0; i < ARRAY_SIZE(otp_cal_regs); i++) {
+		ret[i] = abx500_get_register_interruptible(gpadc->dev,
+			AB8500_OTP_EMUL, otp_cal_regs[i],  &gpadc_cal[i]);
+		if (ret[i] < 0)
+			dev_err(gpadc->dev, "%s: read otp reg 0x%02x failed\n",
+				__func__, otp_cal_regs[i]);
+	}
+
+	/*
+	 * The ADC calibration data is stored in OTP registers.
+	 * The layout of the calibration data is outlined below and a more
+	 * detailed description can be found in UM0836
+	 *
+	 * vm_h/l = vmain_high/low
+	 * bt_h/l = btemp_high/low
+	 * vb_h/l = vbat_high/low
+	 *
+	 * Data bits 8500/9540:
+	 * | 7	   | 6	   | 5	   | 4	   | 3	   | 2	   | 1	   | 0
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * |						   | vm_h9 | vm_h8
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * |		   | vm_h7 | vm_h6 | vm_h5 | vm_h4 | vm_h3 | vm_h2
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | vm_h1 | vm_h0 | vm_l4 | vm_l3 | vm_l2 | vm_l1 | vm_l0 | bt_h9
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | bt_h8 | bt_h7 | bt_h6 | bt_h5 | bt_h4 | bt_h3 | bt_h2 | bt_h1
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | bt_h0 | bt_l4 | bt_l3 | bt_l2 | bt_l1 | bt_l0 | vb_h9 | vb_h8
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | vb_h7 | vb_h6 | vb_h5 | vb_h4 | vb_h3 | vb_h2 | vb_h1 | vb_h0
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | vb_l5 | vb_l4 | vb_l3 | vb_l2 | vb_l1 | vb_l0 |
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 *
+	 * Data bits 8540:
+	 * OTP2
+	 * | 7	   | 6	   | 5	   | 4	   | 3	   | 2	   | 1	   | 0
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * |
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | vm_h9 | vm_h8 | vm_h7 | vm_h6 | vm_h5 | vm_h4 | vm_h3 | vm_h2
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | vm_h1 | vm_h0 | vm_l4 | vm_l3 | vm_l2 | vm_l1 | vm_l0 | bt_h9
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | bt_h8 | bt_h7 | bt_h6 | bt_h5 | bt_h4 | bt_h3 | bt_h2 | bt_h1
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | bt_h0 | bt_l4 | bt_l3 | bt_l2 | bt_l1 | bt_l0 | vb_h9 | vb_h8
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | vb_h7 | vb_h6 | vb_h5 | vb_h4 | vb_h3 | vb_h2 | vb_h1 | vb_h0
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | vb_l5 | vb_l4 | vb_l3 | vb_l2 | vb_l1 | vb_l0 |
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 *
+	 * Data bits 8540:
+	 * OTP4
+	 * | 7	   | 6	   | 5	   | 4	   | 3	   | 2	   | 1	   | 0
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * |					   | ib_h9 | ib_h8 | ib_h7
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | ib_h6 | ib_h5 | ib_h4 | ib_h3 | ib_h2 | ib_h1 | ib_h0 | ib_l5
+	 * |.......|.......|.......|.......|.......|.......|.......|.......
+	 * | ib_l4 | ib_l3 | ib_l2 | ib_l1 | ib_l0 |
+	 *
+	 *
+	 * Ideal output ADC codes corresponding to injected input voltages
+	 * during manufacturing is:
+	 *
+	 * vmain_high: Vin = 19500mV / ADC ideal code = 997
+	 * vmain_low:  Vin = 315mV   / ADC ideal code = 16
+	 * btemp_high: Vin = 1300mV  / ADC ideal code = 985
+	 * btemp_low:  Vin = 21mV    / ADC ideal code = 16
+	 * vbat_high:  Vin = 4700mV  / ADC ideal code = 982
+	 * vbat_low:   Vin = 2380mV  / ADC ideal code = 33
+	 */
+
+	if (is_ab8540(ab8500)) {
+		/* Calculate gain and offset for VMAIN if all reads succeeded*/
+		if (!(ret[1] < 0 || ret[2] < 0)) {
+			vmain_high = (((gpadc_cal[1] & 0xFF) << 2) |
+				((gpadc_cal[2] & 0xC0) >> 6));
+			vmain_low = ((gpadc_cal[2] & 0x3E) >> 1);
+
+			gpadc->cal_data[ADC_INPUT_VMAIN].otp_calib_hi =
+				(u16)vmain_high;
+			gpadc->cal_data[ADC_INPUT_VMAIN].otp_calib_lo =
+				(u16)vmain_low;
+
+			gpadc->cal_data[ADC_INPUT_VMAIN].gain = CALIB_SCALE *
+				(19500 - 315) / (vmain_high - vmain_low);
+			gpadc->cal_data[ADC_INPUT_VMAIN].offset = CALIB_SCALE *
+				19500 - (CALIB_SCALE * (19500 - 315) /
+				(vmain_high - vmain_low)) * vmain_high;
+		} else {
+		gpadc->cal_data[ADC_INPUT_VMAIN].gain = 0;
+		}
+
+		/* Read IBAT calibration Data */
+		for (i = 0; i < ARRAY_SIZE(otp4_cal_regs); i++) {
+			ret_otp4[i] = abx500_get_register_interruptible(
+					gpadc->dev, AB8500_OTP_EMUL,
+					otp4_cal_regs[i],  &gpadc_otp4[i]);
+			if (ret_otp4[i] < 0)
+				dev_err(gpadc->dev,
+					"%s: read otp4 reg 0x%02x failed\n",
+					__func__, otp4_cal_regs[i]);
+		}
+
+		/* Calculate gain and offset for IBAT if all reads succeeded */
+		if (!(ret_otp4[0] < 0 || ret_otp4[1] < 0 || ret_otp4[2] < 0)) {
+			ibat_high = (((gpadc_otp4[0] & 0x07) << 7) |
+				((gpadc_otp4[1] & 0xFE) >> 1));
+			ibat_low = (((gpadc_otp4[1] & 0x01) << 5) |
+				((gpadc_otp4[2] & 0xF8) >> 3));
+
+			gpadc->cal_data[ADC_INPUT_IBAT].otp_calib_hi =
+				(u16)ibat_high;
+			gpadc->cal_data[ADC_INPUT_IBAT].otp_calib_lo =
+				(u16)ibat_low;
+
+			V_gain = ((IBAT_VDROP_H - IBAT_VDROP_L)
+				<< CALIB_SHIFT_IBAT) / (ibat_high - ibat_low);
+
+			V_offset = (IBAT_VDROP_H << CALIB_SHIFT_IBAT) -
+				(((IBAT_VDROP_H - IBAT_VDROP_L) <<
+				CALIB_SHIFT_IBAT) / (ibat_high - ibat_low))
+				* ibat_high;
+			/*
+			 * Result obtained is in mV (at a scale factor),
+			 * we need to calculate gain and offset to get mA
+			 */
+			V2A_gain = (ADC_CH_IBAT_MAX - ADC_CH_IBAT_MIN)/
+				(ADC_CH_IBAT_MAX_V - ADC_CH_IBAT_MIN_V);
+			V2A_offset = ((ADC_CH_IBAT_MAX_V * ADC_CH_IBAT_MIN -
+				ADC_CH_IBAT_MAX * ADC_CH_IBAT_MIN_V)
+				<< CALIB_SHIFT_IBAT)
+				/ (ADC_CH_IBAT_MAX_V - ADC_CH_IBAT_MIN_V);
+
+			gpadc->cal_data[ADC_INPUT_IBAT].gain = V_gain * V2A_gain;
+			gpadc->cal_data[ADC_INPUT_IBAT].offset = V_offset *
+				V2A_gain + V2A_offset;
+		} else {
+			gpadc->cal_data[ADC_INPUT_IBAT].gain = 0;
+		}
+
+		dev_dbg(gpadc->dev, "IBAT gain %llu offset %llu\n",
+			gpadc->cal_data[ADC_INPUT_IBAT].gain,
+			gpadc->cal_data[ADC_INPUT_IBAT].offset);
+	} else {
+		/* Calculate gain and offset for VMAIN if all reads succeeded */
+		if (!(ret[0] < 0 || ret[1] < 0 || ret[2] < 0)) {
+			vmain_high = (((gpadc_cal[0] & 0x03) << 8) |
+				((gpadc_cal[1] & 0x3F) << 2) |
+				((gpadc_cal[2] & 0xC0) >> 6));
+			vmain_low = ((gpadc_cal[2] & 0x3E) >> 1);
+
+			gpadc->cal_data[ADC_INPUT_VMAIN].otp_calib_hi =
+				(u16)vmain_high;
+			gpadc->cal_data[ADC_INPUT_VMAIN].otp_calib_lo =
+				(u16)vmain_low;
+
+			gpadc->cal_data[ADC_INPUT_VMAIN].gain = CALIB_SCALE *
+				(19500 - 315) / (vmain_high - vmain_low);
+
+			gpadc->cal_data[ADC_INPUT_VMAIN].offset = CALIB_SCALE *
+				19500 - (CALIB_SCALE * (19500 - 315) /
+				(vmain_high - vmain_low)) * vmain_high;
+		} else {
+			gpadc->cal_data[ADC_INPUT_VMAIN].gain = 0;
+		}
+	}
+
+	/* Calculate gain and offset for BTEMP if all reads succeeded */
+	if (!(ret[2] < 0 || ret[3] < 0 || ret[4] < 0)) {
+		btemp_high = (((gpadc_cal[2] & 0x01) << 9) |
+			(gpadc_cal[3] << 1) | ((gpadc_cal[4] & 0x80) >> 7));
+		btemp_low = ((gpadc_cal[4] & 0x7C) >> 2);
+
+		gpadc->cal_data[ADC_INPUT_BTEMP].otp_calib_hi = (u16)btemp_high;
+		gpadc->cal_data[ADC_INPUT_BTEMP].otp_calib_lo = (u16)btemp_low;
+
+		gpadc->cal_data[ADC_INPUT_BTEMP].gain =
+			CALIB_SCALE * (1300 - 21) / (btemp_high - btemp_low);
+		gpadc->cal_data[ADC_INPUT_BTEMP].offset = CALIB_SCALE * 1300 -
+			(CALIB_SCALE * (1300 - 21) / (btemp_high - btemp_low))
+			* btemp_high;
+	} else {
+		gpadc->cal_data[ADC_INPUT_BTEMP].gain = 0;
+	}
+
+	/* Calculate gain and offset for VBAT if all reads succeeded */
+	if (!(ret[4] < 0 || ret[5] < 0 || ret[6] < 0)) {
+		vbat_high = (((gpadc_cal[4] & 0x03) << 8) | gpadc_cal[5]);
+		vbat_low = ((gpadc_cal[6] & 0xFC) >> 2);
+
+		gpadc->cal_data[ADC_INPUT_VBAT].otp_calib_hi = (u16)vbat_high;
+		gpadc->cal_data[ADC_INPUT_VBAT].otp_calib_lo = (u16)vbat_low;
+
+		gpadc->cal_data[ADC_INPUT_VBAT].gain = CALIB_SCALE *
+			(4700 - 2380) /	(vbat_high - vbat_low);
+		gpadc->cal_data[ADC_INPUT_VBAT].offset = CALIB_SCALE * 4700 -
+			(CALIB_SCALE * (4700 - 2380) /
+			(vbat_high - vbat_low)) * vbat_high;
+	} else {
+		gpadc->cal_data[ADC_INPUT_VBAT].gain = 0;
+	}
+
+	dev_dbg(gpadc->dev, "VMAIN gain %llu offset %llu\n",
+		gpadc->cal_data[ADC_INPUT_VMAIN].gain,
+		gpadc->cal_data[ADC_INPUT_VMAIN].offset);
+
+	dev_dbg(gpadc->dev, "BTEMP gain %llu offset %llu\n",
+		gpadc->cal_data[ADC_INPUT_BTEMP].gain,
+		gpadc->cal_data[ADC_INPUT_BTEMP].offset);
+
+	dev_dbg(gpadc->dev, "VBAT gain %llu offset %llu\n",
+		gpadc->cal_data[ADC_INPUT_VBAT].gain,
+		gpadc->cal_data[ADC_INPUT_VBAT].offset);
+}
+
+#ifdef CONFIG_PM
+static int ab8500_gpadc_runtime_suspend(struct device *dev)
+{
+	struct ab8500_gpadc *gpadc = dev_get_drvdata(dev);
+
+	regulator_disable(gpadc->regu);
+	return 0;
+}
+
+static int ab8500_gpadc_runtime_resume(struct device *dev)
+{
+	struct ab8500_gpadc *gpadc = dev_get_drvdata(dev);
+	int ret;
+
+	ret = regulator_enable(gpadc->regu);
+	if (ret)
+		dev_err(dev, "Failed to enable vtvout LDO: %d\n", ret);
+	return ret;
+}
+#endif
+
+#ifdef CONFIG_PM_SLEEP
+static int ab8500_gpadc_suspend(struct device *dev)
+{
+	struct ab8500_gpadc *gpadc = dev_get_drvdata(dev);
+
+	mutex_lock(&gpadc->ab8500_gpadc_lock);
+
+	pm_runtime_get_sync(dev);
+
+	regulator_disable(gpadc->regu);
+	return 0;
+}
+
+static int ab8500_gpadc_resume(struct device *dev)
+{
+	struct ab8500_gpadc *gpadc = dev_get_drvdata(dev);
+	int ret;
+
+	ret = regulator_enable(gpadc->regu);
+	if (ret)
+		dev_err(dev, "Failed to enable vtvout LDO: %d\n", ret);
+
+	pm_runtime_mark_last_busy(gpadc->dev);
+	pm_runtime_put_autosuspend(gpadc->dev);
+
+	mutex_unlock(&gpadc->ab8500_gpadc_lock);
+	return ret;
+}
+#endif
+
+static int ab8500_gpadc_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+	struct ab8500_gpadc *gpadc;
+
+	gpadc = devm_kzalloc(&pdev->dev, sizeof(struct ab8500_gpadc), GFP_KERNEL);
+	if (!gpadc) {
+		dev_err(&pdev->dev, "Error: No memory\n");
+		return -ENOMEM;
+	}
+
+	gpadc->irq_sw = platform_get_irq_byname(pdev, "SW_CONV_END");
+	if (gpadc->irq_sw < 0)
+		dev_err(gpadc->dev, "failed to get platform sw_conv_end irq\n");
+
+	gpadc->irq_hw = platform_get_irq_byname(pdev, "HW_CONV_END");
+	if (gpadc->irq_hw < 0)
+		dev_err(gpadc->dev, "failed to get platform hw_conv_end irq\n");
+
+	gpadc->dev = &pdev->dev;
+	gpadc->parent = dev_get_drvdata(pdev->dev.parent);
+	mutex_init(&gpadc->ab8500_gpadc_lock);
+
+	/* Initialize completion used to notify completion of conversion */
+	init_completion(&gpadc->ab8500_gpadc_complete);
+
+	/* Register interrupts */
+	if (gpadc->irq_sw >= 0) {
+		ret = request_threaded_irq(gpadc->irq_sw, NULL,
+			ab8500_bm_gpadcconvend_handler,
+			IRQF_NO_SUSPEND | IRQF_SHARED, "ab8500-gpadc-sw",
+			gpadc);
+		if (ret < 0) {
+			dev_err(gpadc->dev,
+				"Failed to register interrupt irq: %d\n",
+				gpadc->irq_sw);
+			goto fail;
+		}
+	}
+
+	if (gpadc->irq_hw >= 0) {
+		ret = request_threaded_irq(gpadc->irq_hw, NULL,
+			ab8500_bm_gpadcconvend_handler,
+			IRQF_NO_SUSPEND | IRQF_SHARED, "ab8500-gpadc-hw",
+			gpadc);
+		if (ret < 0) {
+			dev_err(gpadc->dev,
+				"Failed to register interrupt irq: %d\n",
+				gpadc->irq_hw);
+			goto fail_irq;
+		}
+	}
+
+	/* VTVout LDO used to power up ab8500-GPADC */
+	gpadc->regu = devm_regulator_get(&pdev->dev, "vddadc");
+	if (IS_ERR(gpadc->regu)) {
+		ret = PTR_ERR(gpadc->regu);
+		dev_err(gpadc->dev, "failed to get vtvout LDO\n");
+		goto fail_irq;
+	}
+
+	platform_set_drvdata(pdev, gpadc);
+
+	ret = regulator_enable(gpadc->regu);
+	if (ret) {
+		dev_err(gpadc->dev, "Failed to enable vtvout LDO: %d\n", ret);
+		goto fail_enable;
+	}
+
+	pm_runtime_set_autosuspend_delay(gpadc->dev, GPADC_AUDOSUSPEND_DELAY);
+	pm_runtime_use_autosuspend(gpadc->dev);
+	pm_runtime_set_active(gpadc->dev);
+	pm_runtime_enable(gpadc->dev);
+
+	ab8500_gpadc_read_calibration_data(gpadc);
+	list_add_tail(&gpadc->node, &ab8500_gpadc_list);
+	dev_dbg(gpadc->dev, "probe success\n");
+
+	return 0;
+
+fail_enable:
+fail_irq:
+	free_irq(gpadc->irq_sw, gpadc);
+	free_irq(gpadc->irq_hw, gpadc);
+fail:
+	return ret;
+}
+
+static int ab8500_gpadc_remove(struct platform_device *pdev)
+{
+	struct ab8500_gpadc *gpadc = platform_get_drvdata(pdev);
+
+	/* remove this gpadc entry from the list */
+	list_del(&gpadc->node);
+	/* remove interrupt  - completion of Sw ADC conversion */
+	if (gpadc->irq_sw >= 0)
+		free_irq(gpadc->irq_sw, gpadc);
+	if (gpadc->irq_hw >= 0)
+		free_irq(gpadc->irq_hw, gpadc);
+
+	pm_runtime_get_sync(gpadc->dev);
+	pm_runtime_disable(gpadc->dev);
+
+	regulator_disable(gpadc->regu);
+
+	pm_runtime_set_suspended(gpadc->dev);
+
+	pm_runtime_put_noidle(gpadc->dev);
+
+	return 0;
+}
+
+static const struct dev_pm_ops ab8500_gpadc_pm_ops = {
+	SET_RUNTIME_PM_OPS(ab8500_gpadc_runtime_suspend,
+			   ab8500_gpadc_runtime_resume,
+			   NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(ab8500_gpadc_suspend,
+				ab8500_gpadc_resume)
+
+};
+
+static struct platform_driver ab8500_gpadc_driver = {
+	.probe = ab8500_gpadc_probe,
+	.remove = ab8500_gpadc_remove,
+	.driver = {
+		.name = "ab8500-gpadc",
+		.pm = &ab8500_gpadc_pm_ops,
+	},
+};
+
+static int __init ab8500_gpadc_init(void)
+{
+	return platform_driver_register(&ab8500_gpadc_driver);
+}
+
+static void __exit ab8500_gpadc_exit(void)
+{
+	platform_driver_unregister(&ab8500_gpadc_driver);
+}
+
+/**
+ * ab8540_gpadc_get_otp() - returns OTP values
+ *
+ */
+void ab8540_gpadc_get_otp(struct ab8500_gpadc *gpadc,
+			u16 *vmain_l, u16 *vmain_h, u16 *btemp_l, u16 *btemp_h,
+			u16 *vbat_l, u16 *vbat_h, u16 *ibat_l, u16 *ibat_h)
+{
+	*vmain_l = gpadc->cal_data[ADC_INPUT_VMAIN].otp_calib_lo;
+	*vmain_h = gpadc->cal_data[ADC_INPUT_VMAIN].otp_calib_hi;
+	*btemp_l = gpadc->cal_data[ADC_INPUT_BTEMP].otp_calib_lo;
+	*btemp_h = gpadc->cal_data[ADC_INPUT_BTEMP].otp_calib_hi;
+	*vbat_l = gpadc->cal_data[ADC_INPUT_VBAT].otp_calib_lo;
+	*vbat_h = gpadc->cal_data[ADC_INPUT_VBAT].otp_calib_hi;
+	*ibat_l = gpadc->cal_data[ADC_INPUT_IBAT].otp_calib_lo;
+	*ibat_h = gpadc->cal_data[ADC_INPUT_IBAT].otp_calib_hi;
+	return ;
+}
+
+subsys_initcall_sync(ab8500_gpadc_init);
+module_exit(ab8500_gpadc_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Arun R Murthy, Daniel Willerud, Johan Palsson,"
+		"M'boumba Cedric Madianga");
+MODULE_ALIAS("platform:ab8500_gpadc");
+MODULE_DESCRIPTION("AB8500 GPADC driver");