/*

   * Copyright 2012 ST Ericsson.
   *

   * Power supply driver for ST Ericsson pm2xxx_charger charger
   *

   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   */
  
  #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/regulator/consumer.h>
  #include <linux/err.h>
  #include <linux/i2c.h>
  #include <linux/workqueue.h>

  #include <linux/mfd/abx500/ab8500.h>
  #include <linux/mfd/abx500/ab8500-bm.h>

  #include <linux/mfd/abx500/ux500_chargalg.h>
  #include <linux/pm2301_charger.h>

  #include <linux/gpio.h>

  #include <linux/pm_runtime.h>

  #include <linux/pm.h>

  #include "pm2301_charger.h"

  
  #define to_pm2xxx_charger_ac_device_info(x) container_of((x), \
  		struct pm2xxx_charger, ac_chg)

  #define SLEEP_MIN		50
  #define SLEEP_MAX		100

  #define PM2XXX_AUTOSUSPEND_DELAY 500

  
  static int pm2xxx_interrupt_registers[] = {
  	PM2XXX_REG_INT1,
  	PM2XXX_REG_INT2,
  	PM2XXX_REG_INT3,
  	PM2XXX_REG_INT4,
  	PM2XXX_REG_INT5,
  	PM2XXX_REG_INT6,
  };

  static enum power_supply_property pm2xxx_charger_ac_props[] = {
  	POWER_SUPPLY_PROP_HEALTH,
  	POWER_SUPPLY_PROP_PRESENT,
  	POWER_SUPPLY_PROP_ONLINE,

  	POWER_SUPPLY_PROP_VOLTAGE_AVG,

  };
  
  static int pm2xxx_charger_voltage_map[] = {
  	3500,
  	3525,
  	3550,
  	3575,
  	3600,
  	3625,
  	3650,
  	3675,
  	3700,
  	3725,
  	3750,
  	3775,
  	3800,
  	3825,
  	3850,
  	3875,
  	3900,
  	3925,
  	3950,
  	3975,
  	4000,
  	4025,
  	4050,
  	4075,
  	4100,
  	4125,
  	4150,
  	4175,
  	4200,
  	4225,
  	4250,
  	4275,
  	4300,
  };
  
  static int pm2xxx_charger_current_map[] = {
  	200,
  	200,
  	400,
  	600,
  	800,
  	1000,
  	1200,
  	1400,
  	1600,
  	1800,
  	2000,
  	2200,
  	2400,
  	2600,
  	2800,
  	3000,
  };

  static const struct i2c_device_id pm2xxx_ident[] = {
  	{ "pm2301", 0 },
  	{ }
  };

  static void set_lpn_pin(struct pm2xxx_charger *pm2)
  {

  	if (!pm2->ac.charger_connected && gpio_is_valid(pm2->lpn_pin)) {
  		gpio_set_value(pm2->lpn_pin, 1);
  		usleep_range(SLEEP_MIN, SLEEP_MAX);
  	}

  }
  
  static void clear_lpn_pin(struct pm2xxx_charger *pm2)
  {

  	if (!pm2->ac.charger_connected && gpio_is_valid(pm2->lpn_pin))
  		gpio_set_value(pm2->lpn_pin, 0);

  }

  static int pm2xxx_reg_read(struct pm2xxx_charger *pm2, int reg, u8 *val)
  {
  	int ret;

  
  	/* wake up the device */
  	pm_runtime_get_sync(pm2->dev);

  
  	ret = i2c_smbus_read_i2c_block_data(pm2->config.pm2xxx_i2c, reg,
  				1, val);
  	if (ret < 0)
  		dev_err(pm2->dev, "Error reading register at 0x%x
  ", reg);

  	else
  		ret = 0;

  	pm_runtime_put_sync(pm2->dev);

  
  	return ret;
  }
  
  static int pm2xxx_reg_write(struct pm2xxx_charger *pm2, int reg, u8 val)
  {
  	int ret;

  
  	/* wake up the device */
  	pm_runtime_get_sync(pm2->dev);

  
  	ret = i2c_smbus_write_i2c_block_data(pm2->config.pm2xxx_i2c, reg,
  				1, &val);
  	if (ret < 0)
  		dev_err(pm2->dev, "Error writing register at 0x%x
  ", reg);

  	else
  		ret = 0;

  	pm_runtime_put_sync(pm2->dev);

  
  	return ret;
  }
  
  static int pm2xxx_charging_enable_mngt(struct pm2xxx_charger *pm2)
  {
  	int ret;
  
  	/* Enable charging */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG2,
  			(PM2XXX_CH_AUTO_RESUME_EN | PM2XXX_CHARGER_ENA));
  
  	return ret;
  }
  
  static int pm2xxx_charging_disable_mngt(struct pm2xxx_charger *pm2)
  {
  	int ret;

  	/* Disable SW EOC ctrl */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_SW_CTRL_REG, PM2XXX_SWCTRL_HW);
  	if (ret < 0) {
  		dev_err(pm2->dev, "%s pm2xxx write failed
  ", __func__);
  		return ret;
  	}

  	/* Disable charging */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG2,
  			(PM2XXX_CH_AUTO_RESUME_DIS | PM2XXX_CHARGER_DIS));

  	if (ret < 0) {
  		dev_err(pm2->dev, "%s pm2xxx write failed
  ", __func__);
  		return ret;
  	}

  	return 0;

  }
  
  static int pm2xxx_charger_batt_therm_mngt(struct pm2xxx_charger *pm2, int val)
  {
  	queue_work(pm2->charger_wq, &pm2->check_main_thermal_prot_work);
  
  	return 0;
  }

  static int pm2xxx_charger_die_therm_mngt(struct pm2xxx_charger *pm2, int val)

  {
  	queue_work(pm2->charger_wq, &pm2->check_main_thermal_prot_work);
  
  	return 0;
  }
  
  static int pm2xxx_charger_ovv_mngt(struct pm2xxx_charger *pm2, int val)
  {

  	dev_err(pm2->dev, "Overvoltage detected
  ");
  	pm2->flags.ovv = true;
  	power_supply_changed(&pm2->ac_chg.psy);

  	/* Schedule a new HW failure check */
  	queue_delayed_work(pm2->charger_wq, &pm2->check_hw_failure_work, 0);

  	return 0;

  }
  
  static int pm2xxx_charger_wd_exp_mngt(struct pm2xxx_charger *pm2, int val)
  {

  	dev_dbg(pm2->dev , "20 minutes watchdog expired
  ");

  
  	pm2->ac.wd_expired = true;
  	power_supply_changed(&pm2->ac_chg.psy);
  
  	return 0;
  }
  
  static int pm2xxx_charger_vbat_lsig_mngt(struct pm2xxx_charger *pm2, int val)
  {

  	int ret;

  	switch (val) {
  	case PM2XXX_INT1_ITVBATLOWR:
  		dev_dbg(pm2->dev, "VBAT grows above VBAT_LOW level
  ");

  		/* Enable SW EOC ctrl */
  		ret = pm2xxx_reg_write(pm2, PM2XXX_SW_CTRL_REG,
  							PM2XXX_SWCTRL_SW);
  		if (ret < 0) {
  			dev_err(pm2->dev, "%s pm2xxx write failed
  ", __func__);
  			return ret;
  		}

  		break;
  
  	case PM2XXX_INT1_ITVBATLOWF:
  		dev_dbg(pm2->dev, "VBAT drops below VBAT_LOW level
  ");

  		/* Disable SW EOC ctrl */
  		ret = pm2xxx_reg_write(pm2, PM2XXX_SW_CTRL_REG,
  							PM2XXX_SWCTRL_HW);
  		if (ret < 0) {
  			dev_err(pm2->dev, "%s pm2xxx write failed
  ", __func__);
  			return ret;
  		}

  		break;
  
  	default:
  		dev_err(pm2->dev, "Unknown VBAT level
  ");
  	}
  
  	return 0;
  }
  
  static int pm2xxx_charger_bat_disc_mngt(struct pm2xxx_charger *pm2, int val)
  {
  	dev_dbg(pm2->dev, "battery disconnected
  ");

  	return 0;

  }
  
  static int pm2xxx_charger_detection(struct pm2xxx_charger *pm2, u8 *val)
  {

  	int ret;

  
  	ret = pm2xxx_reg_read(pm2, PM2XXX_SRCE_REG_INT2, val);
  
  	if (ret < 0) {
  		dev_err(pm2->dev, "Charger detection failed
  ");
  		goto out;
  	}
  
  	*val &= (PM2XXX_INT2_S_ITVPWR1PLUG | PM2XXX_INT2_S_ITVPWR2PLUG);

  out:
  	return ret;
  }
  
  static int pm2xxx_charger_itv_pwr_plug_mngt(struct pm2xxx_charger *pm2, int val)
  {
  
  	int ret;
  	u8 read_val;
  
  	/*
  	 * Since we can't be sure that the events are received
  	 * synchronously, we have the check if the main charger is
  	 * connected by reading the interrupt source register.
  	 */
  	ret = pm2xxx_charger_detection(pm2, &read_val);
  
  	if ((ret == 0) && read_val) {
  		pm2->ac.charger_connected = 1;
  		pm2->ac_conn = true;
  		queue_work(pm2->charger_wq, &pm2->ac_work);
  	}
  
  
  	return ret;
  }
  
  static int pm2xxx_charger_itv_pwr_unplug_mngt(struct pm2xxx_charger *pm2,
  								int val)
  {
  	pm2->ac.charger_connected = 0;
  	queue_work(pm2->charger_wq, &pm2->ac_work);
  
  	return 0;
  }

  static int pm2_int_reg0(void *pm2_data, int val)

  {

  	struct pm2xxx_charger *pm2 = pm2_data;

  	int ret = 0;

  	if (val & PM2XXX_INT1_ITVBATLOWR) {
  		ret = pm2xxx_charger_vbat_lsig_mngt(pm2,
  						PM2XXX_INT1_ITVBATLOWR);
  		if (ret < 0)
  			goto out;
  	}
  
  	if (val & PM2XXX_INT1_ITVBATLOWF) {
  		ret = pm2xxx_charger_vbat_lsig_mngt(pm2,
  						PM2XXX_INT1_ITVBATLOWF);
  		if (ret < 0)
  			goto out;

  	}

  	if (val & PM2XXX_INT1_ITVBATDISCONNECT) {

  		ret = pm2xxx_charger_bat_disc_mngt(pm2,
  				PM2XXX_INT1_ITVBATDISCONNECT);

  		if (ret < 0)
  			goto out;

  	}

  out:

  	return ret;
  }

  static int pm2_int_reg1(void *pm2_data, int val)

  {

  	struct pm2xxx_charger *pm2 = pm2_data;

  	int ret = 0;

  	if (val & (PM2XXX_INT2_ITVPWR1PLUG | PM2XXX_INT2_ITVPWR2PLUG)) {

  		dev_dbg(pm2->dev , "Main charger plugged
  ");

  		ret = pm2xxx_charger_itv_pwr_plug_mngt(pm2, val &

  			(PM2XXX_INT2_ITVPWR1PLUG | PM2XXX_INT2_ITVPWR2PLUG));
  	}

  	if (val &

  		(PM2XXX_INT2_ITVPWR1UNPLUG | PM2XXX_INT2_ITVPWR2UNPLUG)) {
  		dev_dbg(pm2->dev , "Main charger unplugged
  ");

  		ret = pm2xxx_charger_itv_pwr_unplug_mngt(pm2, val &

  						(PM2XXX_INT2_ITVPWR1UNPLUG |
  						PM2XXX_INT2_ITVPWR2UNPLUG));
  	}
  
  	return ret;
  }

  static int pm2_int_reg2(void *pm2_data, int val)

  {

  	struct pm2xxx_charger *pm2 = pm2_data;

  	int ret = 0;

  	if (val & PM2XXX_INT3_ITAUTOTIMEOUTWD)
  		ret = pm2xxx_charger_wd_exp_mngt(pm2, val);

  	if (val & (PM2XXX_INT3_ITCHPRECHARGEWD |

  				PM2XXX_INT3_ITCHCCWD | PM2XXX_INT3_ITCHCVWD)) {
  		dev_dbg(pm2->dev,

  			"Watchdog occurred for precharge, CC and CV charge
  ");

  	}
  
  	return ret;
  }

  static int pm2_int_reg3(void *pm2_data, int val)

  {

  	struct pm2xxx_charger *pm2 = pm2_data;

  	int ret = 0;

  	if (val & (PM2XXX_INT4_ITCHARGINGON)) {

  		dev_dbg(pm2->dev ,
  			"chargind operation has started
  ");
  	}

  	if (val & (PM2XXX_INT4_ITVRESUME)) {

  		dev_dbg(pm2->dev,
  			"battery discharged down to VResume threshold
  ");
  	}

  	if (val & (PM2XXX_INT4_ITBATTFULL)) {

  		dev_dbg(pm2->dev , "battery fully detected
  ");
  	}

  	if (val & (PM2XXX_INT4_ITCVPHASE)) {

  		dev_dbg(pm2->dev, "CV phase enter with 0.5C charging
  ");
  	}

  	if (val & (PM2XXX_INT4_ITVPWR2OVV | PM2XXX_INT4_ITVPWR1OVV)) {

  		pm2->failure_case = VPWR_OVV;

  		ret = pm2xxx_charger_ovv_mngt(pm2, val &

  			(PM2XXX_INT4_ITVPWR2OVV | PM2XXX_INT4_ITVPWR1OVV));
  		dev_dbg(pm2->dev, "VPWR/VSYSTEM overvoltage detected
  ");
  	}

  	if (val & (PM2XXX_INT4_S_ITBATTEMPCOLD |

  				PM2XXX_INT4_S_ITBATTEMPHOT)) {

  		ret = pm2xxx_charger_batt_therm_mngt(pm2, val &
  			(PM2XXX_INT4_S_ITBATTEMPCOLD |
  			PM2XXX_INT4_S_ITBATTEMPHOT));

  		dev_dbg(pm2->dev, "BTEMP is too Low/High
  ");
  	}
  
  	return ret;
  }

  static int pm2_int_reg4(void *pm2_data, int val)

  {

  	struct pm2xxx_charger *pm2 = pm2_data;

  	int ret = 0;

  	if (val & PM2XXX_INT5_ITVSYSTEMOVV) {

  		pm2->failure_case = VSYSTEM_OVV;

  		ret = pm2xxx_charger_ovv_mngt(pm2, val &

  						PM2XXX_INT5_ITVSYSTEMOVV);
  		dev_dbg(pm2->dev, "VSYSTEM overvoltage detected
  ");
  	}

  	if (val & (PM2XXX_INT5_ITTHERMALWARNINGFALL |

  				PM2XXX_INT5_ITTHERMALWARNINGRISE |
  				PM2XXX_INT5_ITTHERMALSHUTDOWNFALL |
  				PM2XXX_INT5_ITTHERMALSHUTDOWNRISE)) {
  		dev_dbg(pm2->dev, "BTEMP die temperature is too Low/High
  ");

  		ret = pm2xxx_charger_die_therm_mngt(pm2, val &

  			(PM2XXX_INT5_ITTHERMALWARNINGFALL |
  			PM2XXX_INT5_ITTHERMALWARNINGRISE |
  			PM2XXX_INT5_ITTHERMALSHUTDOWNFALL |
  			PM2XXX_INT5_ITTHERMALSHUTDOWNRISE));
  	}
  
  	return ret;
  }

  static int pm2_int_reg5(void *pm2_data, int val)

  {

  	struct pm2xxx_charger *pm2 = pm2_data;
  	int ret = 0;

  	if (val & (PM2XXX_INT6_ITVPWR2DROP | PM2XXX_INT6_ITVPWR1DROP)) {

  		dev_dbg(pm2->dev, "VMPWR drop to VBAT level
  ");
  	}

  	if (val & (PM2XXX_INT6_ITVPWR2VALIDRISE |
  			PM2XXX_INT6_ITVPWR1VALIDRISE |
  			PM2XXX_INT6_ITVPWR2VALIDFALL |
  			PM2XXX_INT6_ITVPWR1VALIDFALL)) {

  		dev_dbg(pm2->dev, "Falling/Rising edge on WPWR1/2
  ");
  	}

  	return ret;

  }
  
  static irqreturn_t  pm2xxx_irq_int(int irq, void *data)
  {
  	struct pm2xxx_charger *pm2 = data;

  	struct pm2xxx_interrupts *interrupt = pm2->pm2_int;
  	int i;

  	/* wake up the device */
  	pm_runtime_get_sync(pm2->dev);

  	do {
  		for (i = 0; i < PM2XXX_NUM_INT_REG; i++) {
  			pm2xxx_reg_read(pm2,

  				pm2xxx_interrupt_registers[i],
  				&(interrupt->reg[i]));

  			if (interrupt->reg[i] > 0)
  				interrupt->handler[i](pm2, interrupt->reg[i]);
  		}
  	} while (gpio_get_value(pm2->pdata->gpio_irq_number) == 0);

  	pm_runtime_mark_last_busy(pm2->dev);
  	pm_runtime_put_autosuspend(pm2->dev);

  
  	return IRQ_HANDLED;
  }

  static int pm2xxx_charger_get_ac_cv(struct pm2xxx_charger *pm2)
  {
  	int ret = 0;
  	u8 val;
  
  	if (pm2->ac.charger_connected && pm2->ac.charger_online) {
  
  		ret = pm2xxx_reg_read(pm2, PM2XXX_SRCE_REG_INT4, &val);
  		if (ret < 0) {
  			dev_err(pm2->dev, "%s pm2xxx read failed
  ", __func__);
  			goto out;
  		}
  
  		if (val & PM2XXX_INT4_S_ITCVPHASE)
  			ret = PM2XXX_CONST_VOLT;
  		else
  			ret = PM2XXX_CONST_CURR;
  	}
  out:
  	return ret;
  }

  static int pm2xxx_current_to_regval(int curr)
  {
  	int i;
  
  	if (curr < pm2xxx_charger_current_map[0])
  		return 0;
  
  	for (i = 1; i < ARRAY_SIZE(pm2xxx_charger_current_map); i++) {
  		if (curr < pm2xxx_charger_current_map[i])
  			return (i - 1);
  	}
  
  	i = ARRAY_SIZE(pm2xxx_charger_current_map) - 1;
  	if (curr == pm2xxx_charger_current_map[i])
  		return i;
  	else
  		return -EINVAL;
  }
  
  static int pm2xxx_voltage_to_regval(int curr)
  {
  	int i;
  
  	if (curr < pm2xxx_charger_voltage_map[0])
  		return 0;
  
  	for (i = 1; i < ARRAY_SIZE(pm2xxx_charger_voltage_map); i++) {
  		if (curr < pm2xxx_charger_voltage_map[i])
  			return i - 1;
  	}
  
  	i = ARRAY_SIZE(pm2xxx_charger_voltage_map) - 1;
  	if (curr == pm2xxx_charger_voltage_map[i])
  		return i;
  	else
  		return -EINVAL;
  }
  
  static int pm2xxx_charger_update_charger_current(struct ux500_charger *charger,
  		int ich_out)
  {
  	int ret;
  	int curr_index;
  	struct pm2xxx_charger *pm2;
  	u8 val;
  
  	if (charger->psy.type == POWER_SUPPLY_TYPE_MAINS)
  		pm2 = to_pm2xxx_charger_ac_device_info(charger);
  	else
  		return -ENXIO;
  
  	curr_index = pm2xxx_current_to_regval(ich_out);
  	if (curr_index < 0) {
  		dev_err(pm2->dev,

  			"Charger current too high, charging not started
  ");

  		return -ENXIO;
  	}
  
  	ret = pm2xxx_reg_read(pm2, PM2XXX_BATT_CTRL_REG6, &val);
  	if (ret >= 0) {
  		val &= ~PM2XXX_DIR_CH_CC_CURRENT_MASK;
  		val |= curr_index;
  		ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG6, val);
  		if (ret < 0) {
  			dev_err(pm2->dev,
  				"%s write failed
  ", __func__);
  		}
  	}
  	else
  		dev_err(pm2->dev, "%s read failed
  ", __func__);
  
  	return ret;
  }
  
  static int pm2xxx_charger_ac_get_property(struct power_supply *psy,
  	enum power_supply_property psp,
  	union power_supply_propval *val)
  {
  	struct pm2xxx_charger *pm2;
  
  	pm2 = to_pm2xxx_charger_ac_device_info(psy_to_ux500_charger(psy));
  
  	switch (psp) {
  	case POWER_SUPPLY_PROP_HEALTH:
  		if (pm2->flags.mainextchnotok)
  			val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
  		else if (pm2->ac.wd_expired)
  			val->intval = POWER_SUPPLY_HEALTH_DEAD;
  		else if (pm2->flags.main_thermal_prot)
  			val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;

  		else if (pm2->flags.ovv)
  			val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;

  		else
  			val->intval = POWER_SUPPLY_HEALTH_GOOD;
  		break;
  	case POWER_SUPPLY_PROP_ONLINE:
  		val->intval = pm2->ac.charger_online;
  		break;
  	case POWER_SUPPLY_PROP_PRESENT:
  		val->intval = pm2->ac.charger_connected;
  		break;

  	case POWER_SUPPLY_PROP_VOLTAGE_AVG:
  		pm2->ac.cv_active = pm2xxx_charger_get_ac_cv(pm2);
  		val->intval = pm2->ac.cv_active;
  		break;

  	default:
  		return -EINVAL;
  	}
  	return 0;
  }
  
  static int pm2xxx_charging_init(struct pm2xxx_charger *pm2)
  {
  	int ret = 0;
  
  	/* enable CC and CV watchdog */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG3,
  		(PM2XXX_CH_WD_CV_PHASE_60MIN | PM2XXX_CH_WD_CC_PHASE_60MIN));
  	if( ret < 0)
  		return ret;
  
  	/* enable precharge watchdog */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG4,
  					PM2XXX_CH_WD_PRECH_PHASE_60MIN);

  	/* Disable auto timeout */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG5,
  					PM2XXX_CH_WD_AUTO_TIMEOUT_20MIN);
  
  	/*
       * EOC current level = 100mA
  	 * Precharge current level = 100mA
  	 * CC current level = 1000mA
  	 */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG6,
  		(PM2XXX_DIR_CH_CC_CURRENT_1000MA |
  		PM2XXX_CH_PRECH_CURRENT_100MA |
  		PM2XXX_CH_EOC_CURRENT_100MA));
  
  	/*
       * recharge threshold = 3.8V
  	 * Precharge to CC threshold = 2.9V
  	 */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG7,
  		(PM2XXX_CH_PRECH_VOL_2_9 | PM2XXX_CH_VRESUME_VOL_3_8));
  
  	/* float voltage charger level = 4.2V */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG8,
  		PM2XXX_CH_VOLT_4_2);
  
  	/* Voltage drop between VBAT and VSYS in HW charging = 300mV */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG9,
  		(PM2XXX_CH_150MV_DROP_300MV | PM2XXX_CHARCHING_INFO_DIS |
  		PM2XXX_CH_CC_REDUCED_CURRENT_IDENT |
  		PM2XXX_CH_CC_MODEDROP_DIS));
  
  	/* Input charger level of over voltage = 10V */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_INP_VOLT_VPWR2,
  					PM2XXX_VPWR2_OVV_10);
  	ret = pm2xxx_reg_write(pm2, PM2XXX_INP_VOLT_VPWR1,
  					PM2XXX_VPWR1_OVV_10);
  
  	/* Input charger drop */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_INP_DROP_VPWR2,
  		(PM2XXX_VPWR2_HW_OPT_DIS | PM2XXX_VPWR2_VALID_DIS |
  		PM2XXX_VPWR2_DROP_DIS));
  	ret = pm2xxx_reg_write(pm2, PM2XXX_INP_DROP_VPWR1,
  		(PM2XXX_VPWR1_HW_OPT_DIS | PM2XXX_VPWR1_VALID_DIS |
  		PM2XXX_VPWR1_DROP_DIS));
  
  	/* Disable battery low monitoring */
  	ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_LOW_LEV_COMP_REG,

  		PM2XXX_VBAT_LOW_MONITORING_ENA);

  	return ret;
  }
  
  static int pm2xxx_charger_ac_en(struct ux500_charger *charger,
  	int enable, int vset, int iset)
  {
  	int ret;
  	int volt_index;
  	int curr_index;
  	u8 val;
  
  	struct pm2xxx_charger *pm2 = to_pm2xxx_charger_ac_device_info(charger);
  
  	if (enable) {
  		if (!pm2->ac.charger_connected) {
  			dev_dbg(pm2->dev, "AC charger not connected
  ");
  			return -ENXIO;
  		}
  
  		dev_dbg(pm2->dev, "Enable AC: %dmV %dmA
  ", vset, iset);
  		if (!pm2->vddadc_en_ac) {

  			ret = regulator_enable(pm2->regu);
  			if (ret)
  				dev_warn(pm2->dev,
  					"Failed to enable vddadc regulator
  ");
  			else
  				pm2->vddadc_en_ac = true;

  		}
  
  		ret = pm2xxx_charging_init(pm2);
  		if (ret < 0) {
  			dev_err(pm2->dev, "%s charging init failed
  ",
  					__func__);
  			goto error_occured;
  		}
  
  		volt_index = pm2xxx_voltage_to_regval(vset);
  		curr_index = pm2xxx_current_to_regval(iset);
  
  		if (volt_index < 0 || curr_index < 0) {
  			dev_err(pm2->dev,
  				"Charger voltage or current too high, "
  				"charging not started
  ");
  			return -ENXIO;
  		}
  
  		ret = pm2xxx_reg_read(pm2, PM2XXX_BATT_CTRL_REG8, &val);

  		if (ret < 0) {
  			dev_err(pm2->dev, "%s pm2xxx read failed
  ", __func__);
  			goto error_occured;
  		}
  		val &= ~PM2XXX_CH_VOLT_MASK;
  		val |= volt_index;
  		ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG8, val);
  		if (ret < 0) {
  			dev_err(pm2->dev, "%s pm2xxx write failed
  ", __func__);
  			goto error_occured;

  		}
  
  		ret = pm2xxx_reg_read(pm2, PM2XXX_BATT_CTRL_REG6, &val);

  		if (ret < 0) {
  			dev_err(pm2->dev, "%s pm2xxx read failed
  ", __func__);
  			goto error_occured;
  		}
  		val &= ~PM2XXX_DIR_CH_CC_CURRENT_MASK;
  		val |= curr_index;
  		ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_CTRL_REG6, val);
  		if (ret < 0) {
  			dev_err(pm2->dev, "%s pm2xxx write failed
  ", __func__);
  			goto error_occured;

  		}
  
  		if (!pm2->bat->enable_overshoot) {
  			ret = pm2xxx_reg_read(pm2, PM2XXX_LED_CTRL_REG, &val);

  			if (ret < 0) {
  				dev_err(pm2->dev, "%s pm2xxx read failed
  ",
  								__func__);
  				goto error_occured;
  			}
  			val |= PM2XXX_ANTI_OVERSHOOT_EN;
  			ret = pm2xxx_reg_write(pm2, PM2XXX_LED_CTRL_REG, val);
  			if (ret < 0) {
  				dev_err(pm2->dev, "%s pm2xxx write failed
  ",
  								__func__);
  				goto error_occured;

  			}

  		}
  
  		ret = pm2xxx_charging_enable_mngt(pm2);

  		if (ret < 0) {
  			dev_err(pm2->dev, "Failed to enable"
  						"pm2xxx ac charger
  ");

  			goto error_occured;
  		}
  
  		pm2->ac.charger_online = 1;
  	} else {
  		pm2->ac.charger_online = 0;
  		pm2->ac.wd_expired = false;
  
  		/* Disable regulator if enabled */
  		if (pm2->vddadc_en_ac) {
  			regulator_disable(pm2->regu);
  			pm2->vddadc_en_ac = false;
  		}
  
  		ret = pm2xxx_charging_disable_mngt(pm2);

  		if (ret < 0) {
  			dev_err(pm2->dev, "failed to disable"
  						"pm2xxx ac charger
  ");
  			goto error_occured;

  		}
  
  		dev_dbg(pm2->dev, "PM2301: " "Disabled AC charging
  ");
  	}
  	power_supply_changed(&pm2->ac_chg.psy);
  
  error_occured:
  	return ret;
  }
  
  static int pm2xxx_charger_watchdog_kick(struct ux500_charger *charger)
  {
  	int ret;
  	struct pm2xxx_charger *pm2;
  
  	if (charger->psy.type == POWER_SUPPLY_TYPE_MAINS)
  		pm2 = to_pm2xxx_charger_ac_device_info(charger);
  	else
  		return -ENXIO;
  
  	ret = pm2xxx_reg_write(pm2, PM2XXX_BATT_WD_KICK, WD_TIMER);
  	if (ret)
  		dev_err(pm2->dev, "Failed to kick WD!
  ");
  
  	return ret;
  }
  
  static void pm2xxx_charger_ac_work(struct work_struct *work)
  {
  	struct pm2xxx_charger *pm2 = container_of(work,
  		struct pm2xxx_charger, ac_work);
  
  
  	power_supply_changed(&pm2->ac_chg.psy);
  	sysfs_notify(&pm2->ac_chg.psy.dev->kobj, NULL, "present");
  };

  static void pm2xxx_charger_check_hw_failure_work(struct work_struct *work)
  {
  	u8 reg_value;
  
  	struct pm2xxx_charger *pm2 = container_of(work,
  		struct pm2xxx_charger, check_hw_failure_work.work);
  
  	if (pm2->flags.ovv) {
  		pm2xxx_reg_read(pm2, PM2XXX_SRCE_REG_INT4, &reg_value);
  
  		if (!(reg_value & (PM2XXX_INT4_S_ITVPWR1OVV |
  					PM2XXX_INT4_S_ITVPWR2OVV))) {
  			pm2->flags.ovv = false;
  			power_supply_changed(&pm2->ac_chg.psy);
  		}
  	}
  
  	/* If we still have a failure, schedule a new check */
  	if (pm2->flags.ovv) {
  		queue_delayed_work(pm2->charger_wq,
  			&pm2->check_hw_failure_work, round_jiffies(HZ));
  	}
  }

  static void pm2xxx_charger_check_main_thermal_prot_work(
  	struct work_struct *work)
  {

  	int ret;
  	u8 val;
  
  	struct pm2xxx_charger *pm2 = container_of(work, struct pm2xxx_charger,
  					check_main_thermal_prot_work);
  
  	/* Check if die temp warning is still active */
  	ret = pm2xxx_reg_read(pm2, PM2XXX_SRCE_REG_INT5, &val);
  	if (ret < 0) {
  		dev_err(pm2->dev, "%s pm2xxx read failed
  ", __func__);
  		return;
  	}
  	if (val & (PM2XXX_INT5_S_ITTHERMALWARNINGRISE
  			| PM2XXX_INT5_S_ITTHERMALSHUTDOWNRISE))
  		pm2->flags.main_thermal_prot = true;
  	else if (val & (PM2XXX_INT5_S_ITTHERMALWARNINGFALL
  				| PM2XXX_INT5_S_ITTHERMALSHUTDOWNFALL))
  		pm2->flags.main_thermal_prot = false;
  
  	power_supply_changed(&pm2->ac_chg.psy);
  }

  static struct pm2xxx_interrupts pm2xxx_int = {
  	.handler[0] = pm2_int_reg0,
  	.handler[1] = pm2_int_reg1,
  	.handler[2] = pm2_int_reg2,
  	.handler[3] = pm2_int_reg3,
  	.handler[4] = pm2_int_reg4,
  	.handler[5] = pm2_int_reg5,
  };

  static struct pm2xxx_irq pm2xxx_charger_irq[] = {
  	{"PM2XXX_IRQ_INT", pm2xxx_irq_int},
  };

  #ifdef CONFIG_PM
  
  #ifdef CONFIG_PM_SLEEP
  
  static int pm2xxx_wall_charger_resume(struct device *dev)

  {

  	struct i2c_client *i2c_client = to_i2c_client(dev);

  	struct pm2xxx_charger *pm2;
  
  	pm2 =  (struct pm2xxx_charger *)i2c_get_clientdata(i2c_client);
  	set_lpn_pin(pm2);
  
  	/* If we still have a HW failure, schedule a new check */
  	if (pm2->flags.ovv)
  		queue_delayed_work(pm2->charger_wq,
  				&pm2->check_hw_failure_work, 0);

  	return 0;
  }

  static int pm2xxx_wall_charger_suspend(struct device *dev)

  {

  	struct i2c_client *i2c_client = to_i2c_client(dev);

  	struct pm2xxx_charger *pm2;
  
  	pm2 =  (struct pm2xxx_charger *)i2c_get_clientdata(i2c_client);
  	clear_lpn_pin(pm2);
  
  	/* Cancel any pending HW failure check */
  	if (delayed_work_pending(&pm2->check_hw_failure_work))
  		cancel_delayed_work(&pm2->check_hw_failure_work);
  
  	flush_work(&pm2->ac_work);
  	flush_work(&pm2->check_main_thermal_prot_work);

  	return 0;
  }

  #endif

  static int  pm2xxx_runtime_suspend(struct device *dev)
  {
  	struct i2c_client *pm2xxx_i2c_client = to_i2c_client(dev);
  	struct pm2xxx_charger *pm2;

  
  	pm2 = (struct pm2xxx_charger *)i2c_get_clientdata(pm2xxx_i2c_client);

  	clear_lpn_pin(pm2);

  	return 0;

  }
  
  static int  pm2xxx_runtime_resume(struct device *dev)
  {
  	struct i2c_client *pm2xxx_i2c_client = to_i2c_client(dev);
  	struct pm2xxx_charger *pm2;

  
  	pm2 = (struct pm2xxx_charger *)i2c_get_clientdata(pm2xxx_i2c_client);

  
  	if (gpio_is_valid(pm2->lpn_pin) && gpio_get_value(pm2->lpn_pin) == 0)
  		set_lpn_pin(pm2);

  	return 0;

  }
  
  static const struct dev_pm_ops pm2xxx_pm_ops = {

  	SET_SYSTEM_SLEEP_PM_OPS(pm2xxx_wall_charger_suspend,
  		pm2xxx_wall_charger_resume)
  	SET_RUNTIME_PM_OPS(pm2xxx_runtime_suspend, pm2xxx_runtime_resume, NULL)

  };
  #define  PM2XXX_PM_OPS (&pm2xxx_pm_ops)
  #else
  #define  PM2XXX_PM_OPS  NULL
  #endif

  static int pm2xxx_wall_charger_probe(struct i2c_client *i2c_client,

  		const struct i2c_device_id *id)
  {
  	struct pm2xxx_platform_data *pl_data = i2c_client->dev.platform_data;
  	struct pm2xxx_charger *pm2;
  	int ret = 0;
  	u8 val;

  	int i;

  	if (!pl_data) {
  		dev_err(&i2c_client->dev, "No platform data supplied
  ");
  		return -EINVAL;
  	}

  	pm2 = kzalloc(sizeof(struct pm2xxx_charger), GFP_KERNEL);
  	if (!pm2) {

  		dev_err(&i2c_client->dev, "pm2xxx_charger allocation failed
  ");

  		return -ENOMEM;
  	}
  
  	/* get parent data */
  	pm2->dev = &i2c_client->dev;

  	pm2->pm2_int = &pm2xxx_int;

  	/* get charger spcific platform data */
  	if (!pl_data->wall_charger) {
  		dev_err(pm2->dev, "no charger platform data supplied
  ");
  		ret = -EINVAL;
  		goto free_device_info;
  	}
  
  	pm2->pdata = pl_data->wall_charger;
  
  	/* get battery specific platform data */
  	if (!pl_data->battery) {
  		dev_err(pm2->dev, "no battery platform data supplied
  ");
  		ret = -EINVAL;
  		goto free_device_info;
  	}
  
  	pm2->bat = pl_data->battery;
  
  	if (!i2c_check_functionality(i2c_client->adapter,
  			I2C_FUNC_SMBUS_BYTE_DATA |
  			I2C_FUNC_SMBUS_READ_WORD_DATA)) {
  		ret = -ENODEV;
  		dev_info(pm2->dev, "pm2301 i2c_check_functionality failed
  ");
  		goto free_device_info;
  	}
  
  	pm2->config.pm2xxx_i2c = i2c_client;
  	pm2->config.pm2xxx_id = (struct i2c_device_id *) id;
  	i2c_set_clientdata(i2c_client, pm2);
  
  	/* AC supply */
  	/* power_supply base class */
  	pm2->ac_chg.psy.name = pm2->pdata->label;
  	pm2->ac_chg.psy.type = POWER_SUPPLY_TYPE_MAINS;
  	pm2->ac_chg.psy.properties = pm2xxx_charger_ac_props;
  	pm2->ac_chg.psy.num_properties = ARRAY_SIZE(pm2xxx_charger_ac_props);
  	pm2->ac_chg.psy.get_property = pm2xxx_charger_ac_get_property;
  	pm2->ac_chg.psy.supplied_to = pm2->pdata->supplied_to;
  	pm2->ac_chg.psy.num_supplicants = pm2->pdata->num_supplicants;
  	/* pm2xxx_charger sub-class */
  	pm2->ac_chg.ops.enable = &pm2xxx_charger_ac_en;
  	pm2->ac_chg.ops.kick_wd = &pm2xxx_charger_watchdog_kick;
  	pm2->ac_chg.ops.update_curr = &pm2xxx_charger_update_charger_current;
  	pm2->ac_chg.max_out_volt = pm2xxx_charger_voltage_map[
  		ARRAY_SIZE(pm2xxx_charger_voltage_map) - 1];
  	pm2->ac_chg.max_out_curr = pm2xxx_charger_current_map[
  		ARRAY_SIZE(pm2xxx_charger_current_map) - 1];

  	pm2->ac_chg.wdt_refresh = WD_KICK_INTERVAL;

  	pm2->ac_chg.enabled = true;

  	pm2->ac_chg.external = true;

  
  	/* Create a work queue for the charger */

  	pm2->charger_wq = create_singlethread_workqueue("pm2xxx_charger_wq");

  	if (pm2->charger_wq == NULL) {

  		ret = -ENOMEM;

  		dev_err(pm2->dev, "failed to create work queue
  ");
  		goto free_device_info;
  	}
  
  	/* Init work for charger detection */
  	INIT_WORK(&pm2->ac_work, pm2xxx_charger_ac_work);
  
  	/* Init work for checking HW status */
  	INIT_WORK(&pm2->check_main_thermal_prot_work,
  		pm2xxx_charger_check_main_thermal_prot_work);

  	/* Init work for HW failure check */
  	INIT_DEFERRABLE_WORK(&pm2->check_hw_failure_work,
  		pm2xxx_charger_check_hw_failure_work);

  	/*
  	 * VDD ADC supply needs to be enabled from this driver when there
  	 * is a charger connected to avoid erroneous BTEMP_HIGH/LOW
  	 * interrupts during charging
  	 */
  	pm2->regu = regulator_get(pm2->dev, "vddadc");
  	if (IS_ERR(pm2->regu)) {
  		ret = PTR_ERR(pm2->regu);
  		dev_err(pm2->dev, "failed to get vddadc regulator
  ");
  		goto free_charger_wq;
  	}
  
  	/* Register AC charger class */
  	ret = power_supply_register(pm2->dev, &pm2->ac_chg.psy);
  	if (ret) {
  		dev_err(pm2->dev, "failed to register AC charger
  ");
  		goto free_regulator;
  	}
  
  	/* Register interrupts */

  	ret = request_threaded_irq(gpio_to_irq(pm2->pdata->gpio_irq_number),
  				NULL,

  				pm2xxx_charger_irq[0].isr,
  				pm2->pdata->irq_type,
  				pm2xxx_charger_irq[0].name, pm2);
  
  	if (ret != 0) {
  		dev_err(pm2->dev, "failed to request %s IRQ %d: %d
  ",

  		pm2xxx_charger_irq[0].name,
  			gpio_to_irq(pm2->pdata->gpio_irq_number), ret);

  		goto unregister_pm2xxx_charger;
  	}

  	ret = pm_runtime_set_active(pm2->dev);
  	if (ret)
  		dev_err(pm2->dev, "set active Error
  ");

  	pm_runtime_enable(pm2->dev);
  	pm_runtime_set_autosuspend_delay(pm2->dev, PM2XXX_AUTOSUSPEND_DELAY);
  	pm_runtime_use_autosuspend(pm2->dev);
  	pm_runtime_resume(pm2->dev);

  	/* pm interrupt can wake up system */

  	ret = enable_irq_wake(gpio_to_irq(pm2->pdata->gpio_irq_number));

  	if (ret) {
  		dev_err(pm2->dev, "failed to set irq wake
  ");
  		goto unregister_pm2xxx_interrupt;

  	}

  	mutex_init(&pm2->lock);

  	if (gpio_is_valid(pm2->pdata->lpn_gpio)) {
  		/* get lpn GPIO from platform data */
  		pm2->lpn_pin = pm2->pdata->lpn_gpio;

  		/*
  		 * Charger detection mechanism requires pulling up the LPN pin
  		 * while i2c communication if Charger is not connected
  		 * LPN pin of PM2301 is GPIO60 of AB9540
  		 */
  		ret = gpio_request(pm2->lpn_pin, "pm2301_lpm_gpio");
  
  		if (ret < 0) {
  			dev_err(pm2->dev, "pm2301_lpm_gpio request failed
  ");
  			goto disable_pm2_irq_wake;
  		}
  		ret = gpio_direction_output(pm2->lpn_pin, 0);
  		if (ret < 0) {
  			dev_err(pm2->dev, "pm2301_lpm_gpio direction failed
  ");
  			goto free_gpio;
  		}
  		set_lpn_pin(pm2);

  	}

  	/* read  interrupt registers */
  	for (i = 0; i < PM2XXX_NUM_INT_REG; i++)
  		pm2xxx_reg_read(pm2,
  			pm2xxx_interrupt_registers[i],
  			&val);

  	ret = pm2xxx_charger_detection(pm2, &val);
  
  	if ((ret == 0) && val) {
  		pm2->ac.charger_connected = 1;

  		ab8500_override_turn_on_stat(~AB8500_POW_KEY_1_ON,
  					     AB8500_MAIN_CH_DET);

  		pm2->ac_conn = true;
  		power_supply_changed(&pm2->ac_chg.psy);
  		sysfs_notify(&pm2->ac_chg.psy.dev->kobj, NULL, "present");
  	}
  
  	return 0;

  free_gpio:

  	if (gpio_is_valid(pm2->lpn_pin))
  		gpio_free(pm2->lpn_pin);

  disable_pm2_irq_wake:

  	disable_irq_wake(gpio_to_irq(pm2->pdata->gpio_irq_number));

  unregister_pm2xxx_interrupt:
  	/* disable interrupt */

  	free_irq(gpio_to_irq(pm2->pdata->gpio_irq_number), pm2);

  unregister_pm2xxx_charger:
  	/* unregister power supply */
  	power_supply_unregister(&pm2->ac_chg.psy);
  free_regulator:
  	/* disable the regulator */
  	regulator_put(pm2->regu);
  free_charger_wq:
  	destroy_workqueue(pm2->charger_wq);
  free_device_info:
  	kfree(pm2);

  	return ret;
  }

  static int pm2xxx_wall_charger_remove(struct i2c_client *i2c_client)

  {
  	struct pm2xxx_charger *pm2 = i2c_get_clientdata(i2c_client);

  	/* Disable pm_runtime */
  	pm_runtime_disable(pm2->dev);

  	/* Disable AC charging */
  	pm2xxx_charger_ac_en(&pm2->ac_chg, false, 0, 0);

  	/* Disable wake by pm interrupt */

  	disable_irq_wake(gpio_to_irq(pm2->pdata->gpio_irq_number));

  	/* Disable interrupts */

  	free_irq(gpio_to_irq(pm2->pdata->gpio_irq_number), pm2);

  
  	/* Delete the work queue */
  	destroy_workqueue(pm2->charger_wq);
  
  	flush_scheduled_work();
  
  	/* disable the regulator */
  	regulator_put(pm2->regu);
  
  	power_supply_unregister(&pm2->ac_chg.psy);

  	if (gpio_is_valid(pm2->lpn_pin))
  		gpio_free(pm2->lpn_pin);

  	kfree(pm2);
  
  	return 0;
  }
  
  static const struct i2c_device_id pm2xxx_id[] = {
  	{ "pm2301", 0 },
  	{ }
  };
  
  MODULE_DEVICE_TABLE(i2c, pm2xxx_id);
  
  static struct i2c_driver pm2xxx_charger_driver = {
  	.probe = pm2xxx_wall_charger_probe,

  	.remove = pm2xxx_wall_charger_remove,

  	.driver = {
  		.name = "pm2xxx-wall_charger",
  		.owner = THIS_MODULE,

  		.pm = PM2XXX_PM_OPS,

  	},
  	.id_table = pm2xxx_id,
  };
  
  static int __init pm2xxx_charger_init(void)
  {
  	return i2c_add_driver(&pm2xxx_charger_driver);
  }
  
  static void __exit pm2xxx_charger_exit(void)
  {
  	i2c_del_driver(&pm2xxx_charger_driver);
  }

  device_initcall_sync(pm2xxx_charger_init);

  module_exit(pm2xxx_charger_exit);
  
  MODULE_LICENSE("GPL v2");
  MODULE_AUTHOR("Rajkumar kasirajan, Olivier Launay");

  MODULE_ALIAS("i2c:pm2xxx-charger");

  MODULE_DESCRIPTION("PM2xxx charger management driver");