text: /*
   * Power supply driver for the Active-semi ACT8945A PMIC
   *
   * Copyright (C) 2015 Atmel Corporation
   *
   * Author: Wenyou Yang <wenyou.yang@atmel.com>
   *
   * 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/interrupt.h>
  #include <linux/module.h>
  #include <linux/of.h>
  #include <linux/of_irq.h>
  #include <linux/platform_device.h>
  #include <linux/power_supply.h>
  #include <linux/regmap.h>
  #include <linux/gpio/consumer.h>
  
  static const char *act8945a_charger_model = "ACT8945A";
  static const char *act8945a_charger_manufacturer = "Active-semi";
  
  /**
   * ACT8945A Charger Register Map
   */
  
  /* 0x70: Reserved */
  #define ACT8945A_APCH_CFG		0x71
  #define ACT8945A_APCH_STATUS		0x78
  #define ACT8945A_APCH_CTRL		0x79
  #define ACT8945A_APCH_STATE		0x7A
  
  /* ACT8945A_APCH_CFG */
  #define APCH_CFG_OVPSET			(0x3 << 0)
  #define APCH_CFG_OVPSET_6V6		(0x0 << 0)
  #define APCH_CFG_OVPSET_7V		(0x1 << 0)
  #define APCH_CFG_OVPSET_7V5		(0x2 << 0)
  #define APCH_CFG_OVPSET_8V		(0x3 << 0)
  #define APCH_CFG_PRETIMO		(0x3 << 2)
  #define APCH_CFG_PRETIMO_40_MIN		(0x0 << 2)
  #define APCH_CFG_PRETIMO_60_MIN		(0x1 << 2)
  #define APCH_CFG_PRETIMO_80_MIN		(0x2 << 2)
  #define APCH_CFG_PRETIMO_DISABLED	(0x3 << 2)
  #define APCH_CFG_TOTTIMO		(0x3 << 4)
  #define APCH_CFG_TOTTIMO_3_HOUR		(0x0 << 4)
  #define APCH_CFG_TOTTIMO_4_HOUR		(0x1 << 4)
  #define APCH_CFG_TOTTIMO_5_HOUR		(0x2 << 4)
  #define APCH_CFG_TOTTIMO_DISABLED	(0x3 << 4)
  #define APCH_CFG_SUSCHG			(0x1 << 7)
  
  #define APCH_STATUS_CHGDAT		BIT(0)
  #define APCH_STATUS_INDAT		BIT(1)
  #define APCH_STATUS_TEMPDAT		BIT(2)
  #define APCH_STATUS_TIMRDAT		BIT(3)
  #define APCH_STATUS_CHGSTAT		BIT(4)
  #define APCH_STATUS_INSTAT		BIT(5)
  #define APCH_STATUS_TEMPSTAT		BIT(6)
  #define APCH_STATUS_TIMRSTAT		BIT(7)
  
  #define APCH_CTRL_CHGEOCOUT		BIT(0)
  #define APCH_CTRL_INDIS			BIT(1)
  #define APCH_CTRL_TEMPOUT		BIT(2)
  #define APCH_CTRL_TIMRPRE		BIT(3)
  #define APCH_CTRL_CHGEOCIN		BIT(4)
  #define APCH_CTRL_INCON			BIT(5)
  #define APCH_CTRL_TEMPIN		BIT(6)
  #define APCH_CTRL_TIMRTOT		BIT(7)
  
  #define APCH_STATE_ACINSTAT		(0x1 << 1)
  #define APCH_STATE_CSTATE		(0x3 << 4)
  #define APCH_STATE_CSTATE_SHIFT		4
  #define APCH_STATE_CSTATE_DISABLED	0x00
  #define APCH_STATE_CSTATE_EOC		0x01
  #define APCH_STATE_CSTATE_FAST		0x02
  #define APCH_STATE_CSTATE_PRE		0x03
  
  struct act8945a_charger {
  	struct power_supply *psy;
  	struct power_supply_desc desc;
  	struct regmap *regmap;
  	struct work_struct work;
  
  	bool init_done;
  	struct gpio_desc *lbo_gpio;
  	struct gpio_desc *chglev_gpio;
  };
  
  static int act8945a_get_charger_state(struct regmap *regmap, int *val)
  {
  	int ret;
  	unsigned int status, state;
  
  	ret = regmap_read(regmap, ACT8945A_APCH_STATUS, &status);
  	if (ret < 0)
  		return ret;
  
  	ret = regmap_read(regmap, ACT8945A_APCH_STATE, &state);
  	if (ret < 0)
  		return ret;
  
  	state &= APCH_STATE_CSTATE;
  	state >>= APCH_STATE_CSTATE_SHIFT;
  
  	switch (state) {
  	case APCH_STATE_CSTATE_PRE:
  	case APCH_STATE_CSTATE_FAST:
  		*val = POWER_SUPPLY_STATUS_CHARGING;
  		break;
  	case APCH_STATE_CSTATE_EOC:
  		if (status & APCH_STATUS_CHGDAT)
  			*val = POWER_SUPPLY_STATUS_FULL;
  		else
  			*val = POWER_SUPPLY_STATUS_CHARGING;
  		break;
  	case APCH_STATE_CSTATE_DISABLED:
  	default:
  		if (!(status & APCH_STATUS_INDAT))
  			*val = POWER_SUPPLY_STATUS_DISCHARGING;
  		else
  			*val = POWER_SUPPLY_STATUS_NOT_CHARGING;
  		break;
  	}
  
  	return 0;
  }
  
  static int act8945a_get_charge_type(struct regmap *regmap, int *val)
  {
  	int ret;
  	unsigned int status, state;
  
  	ret = regmap_read(regmap, ACT8945A_APCH_STATUS, &status);
  	if (ret < 0)
  		return ret;
  
  	ret = regmap_read(regmap, ACT8945A_APCH_STATE, &state);
  	if (ret < 0)
  		return ret;
  
  	state &= APCH_STATE_CSTATE;
  	state >>= APCH_STATE_CSTATE_SHIFT;
  
  	switch (state) {
  	case APCH_STATE_CSTATE_PRE:
  		*val = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
  		break;
  	case APCH_STATE_CSTATE_FAST:
  		*val = POWER_SUPPLY_CHARGE_TYPE_FAST;
  		break;
  	case APCH_STATE_CSTATE_EOC:
  		*val = POWER_SUPPLY_CHARGE_TYPE_NONE;
  		break;
  	case APCH_STATE_CSTATE_DISABLED:
  	default:
  		if (!(status & APCH_STATUS_INDAT))
  			*val = POWER_SUPPLY_CHARGE_TYPE_NONE;
  		else
  			*val = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
  		break;
  	}
  
  	return 0;
  }
  
  static int act8945a_get_battery_health(struct regmap *regmap, int *val)
  {
  	int ret;
  	unsigned int status, state, config;
  
  	ret = regmap_read(regmap, ACT8945A_APCH_STATUS, &status);
  	if (ret < 0)
  		return ret;
  
  	ret = regmap_read(regmap, ACT8945A_APCH_CFG, &config);
  	if (ret < 0)
  		return ret;
  
  	ret = regmap_read(regmap, ACT8945A_APCH_STATE, &state);
  	if (ret < 0)
  		return ret;
  
  	state &= APCH_STATE_CSTATE;
  	state >>= APCH_STATE_CSTATE_SHIFT;
  
  	switch (state) {
  	case APCH_STATE_CSTATE_DISABLED:
  		if (config & APCH_CFG_SUSCHG) {
  			*val = POWER_SUPPLY_HEALTH_UNKNOWN;
  		} else if (status & APCH_STATUS_INDAT) {
  			if (!(status & APCH_STATUS_TEMPDAT))
  				*val = POWER_SUPPLY_HEALTH_OVERHEAT;
  			else if (status & APCH_STATUS_TIMRDAT)
  				*val = POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE;
  			else
  				*val = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
  		} else {
  			*val = POWER_SUPPLY_HEALTH_GOOD;
  		}
  		break;
  	case APCH_STATE_CSTATE_PRE:
  	case APCH_STATE_CSTATE_FAST:
  	case APCH_STATE_CSTATE_EOC:
  	default:
  		*val = POWER_SUPPLY_HEALTH_GOOD;
  		break;
  	}
  
  	return 0;
  }
  
  static int act8945a_get_capacity_level(struct act8945a_charger *charger,
  				       struct regmap *regmap, int *val)
  {
  	int ret;
  	unsigned int status, state, config;
  	int lbo_level = gpiod_get_value(charger->lbo_gpio);
  
  	ret = regmap_read(regmap, ACT8945A_APCH_STATUS, &status);
  	if (ret < 0)
  		return ret;
  
  	ret = regmap_read(regmap, ACT8945A_APCH_CFG, &config);
  	if (ret < 0)
  		return ret;
  
  	ret = regmap_read(regmap, ACT8945A_APCH_STATE, &state);
  	if (ret < 0)
  		return ret;
  
  	state &= APCH_STATE_CSTATE;
  	state >>= APCH_STATE_CSTATE_SHIFT;
  
  	switch (state) {
  	case APCH_STATE_CSTATE_PRE:
  		*val = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
  		break;
  	case APCH_STATE_CSTATE_FAST:
  		if (lbo_level)
  			*val = POWER_SUPPLY_CAPACITY_LEVEL_HIGH;
  		else
  			*val = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
  		break;
  	case APCH_STATE_CSTATE_EOC:
  		if (status & APCH_STATUS_CHGDAT)
  			*val = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
  		else
  			*val = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
  		break;
  	case APCH_STATE_CSTATE_DISABLED:
  	default:
  		if (config & APCH_CFG_SUSCHG) {
  			*val = POWER_SUPPLY_CAPACITY_LEVEL_UNKNOWN;
  		} else {
  			*val = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
  			if (!(status & APCH_STATUS_INDAT)) {
  				if (!lbo_level)
  					*val = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
  			}
  		}
  		break;
  	}
  
  	return 0;
  }
  
  #define MAX_CURRENT_USB_HIGH	450000
  #define MAX_CURRENT_USB_LOW	90000
  #define MAX_CURRENT_USB_PRE	45000
  /*
   * Riset(K) = 2336 * (1V/Ichg(mA)) - 0.205
   * Riset = 2.43K
   */
  #define MAX_CURRENT_AC_HIGH		886527
  #define MAX_CURRENT_AC_LOW		117305
  #define MAX_CURRENT_AC_HIGH_PRE		88653
  #define MAX_CURRENT_AC_LOW_PRE		11731
  
  static int act8945a_get_current_max(struct act8945a_charger *charger,
  				    struct regmap *regmap, int *val)
  {
  	int ret;
  	unsigned int status, state;
  	unsigned int acin_state;
  	int chgin_level = gpiod_get_value(charger->chglev_gpio);
  
  	ret = regmap_read(regmap, ACT8945A_APCH_STATUS, &status);
  	if (ret < 0)
  		return ret;
  
  	ret = regmap_read(regmap, ACT8945A_APCH_STATE, &state);
  	if (ret < 0)
  		return ret;
  
  	acin_state = (state & APCH_STATE_ACINSTAT) >> 1;
  
  	state &= APCH_STATE_CSTATE;
  	state >>= APCH_STATE_CSTATE_SHIFT;
  
  	switch (state) {
  	case APCH_STATE_CSTATE_PRE:
  		if (acin_state) {
  			if (chgin_level)
  				*val = MAX_CURRENT_AC_HIGH_PRE;
  			else
  				*val = MAX_CURRENT_AC_LOW_PRE;
  		} else {
  			*val = MAX_CURRENT_USB_PRE;
  		}
  		break;
  	case APCH_STATE_CSTATE_FAST:
  		if (acin_state) {
  			if (chgin_level)
  				*val = MAX_CURRENT_AC_HIGH;
  			else
  				*val = MAX_CURRENT_AC_LOW;
  		} else {
  			if (chgin_level)
  				*val = MAX_CURRENT_USB_HIGH;
  			else
  				*val = MAX_CURRENT_USB_LOW;
  		}
  		break;
  	case APCH_STATE_CSTATE_EOC:
  	case APCH_STATE_CSTATE_DISABLED:
  	default:
  		*val = 0;
  		break;
  	}
  
  	return 0;
  }
  
  static enum power_supply_property act8945a_charger_props[] = {
  	POWER_SUPPLY_PROP_STATUS,
  	POWER_SUPPLY_PROP_CHARGE_TYPE,
  	POWER_SUPPLY_PROP_TECHNOLOGY,
  	POWER_SUPPLY_PROP_HEALTH,
  	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
  	POWER_SUPPLY_PROP_CURRENT_MAX,
  	POWER_SUPPLY_PROP_MODEL_NAME,
  	POWER_SUPPLY_PROP_MANUFACTURER
  };
  
  static int act8945a_charger_get_property(struct power_supply *psy,
  					 enum power_supply_property prop,
  					 union power_supply_propval *val)
  {
  	struct act8945a_charger *charger = power_supply_get_drvdata(psy);
  	struct regmap *regmap = charger->regmap;
  	int ret = 0;
  
  	switch (prop) {
  	case POWER_SUPPLY_PROP_STATUS:
  		ret = act8945a_get_charger_state(regmap, &val->intval);
  		break;
  	case POWER_SUPPLY_PROP_CHARGE_TYPE:
  		ret = act8945a_get_charge_type(regmap, &val->intval);
  		break;
  	case POWER_SUPPLY_PROP_TECHNOLOGY:
  		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
  		break;
  	case POWER_SUPPLY_PROP_HEALTH:
  		ret = act8945a_get_battery_health(regmap, &val->intval);
  		break;
  	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
  		ret = act8945a_get_capacity_level(charger,
  						  regmap, &val->intval);
  		break;
  	case POWER_SUPPLY_PROP_CURRENT_MAX:
  		ret = act8945a_get_current_max(charger,
  					       regmap, &val->intval);
  		break;
  	case POWER_SUPPLY_PROP_MODEL_NAME:
  		val->strval = act8945a_charger_model;
  		break;
  	case POWER_SUPPLY_PROP_MANUFACTURER:
  		val->strval = act8945a_charger_manufacturer;
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	return ret;
  }
  
  static int act8945a_enable_interrupt(struct act8945a_charger *charger)
  {
  	struct regmap *regmap = charger->regmap;
  	unsigned char ctrl;
  	int ret;
  
  	ctrl = APCH_CTRL_CHGEOCOUT | APCH_CTRL_CHGEOCIN |
  	       APCH_CTRL_INDIS | APCH_CTRL_INCON |
  	       APCH_CTRL_TEMPOUT | APCH_CTRL_TEMPIN |
  	       APCH_CTRL_TIMRPRE | APCH_CTRL_TIMRTOT;
  	ret = regmap_write(regmap, ACT8945A_APCH_CTRL, ctrl);
  	if (ret)
  		return ret;
  
  	ctrl = APCH_STATUS_CHGSTAT | APCH_STATUS_INSTAT |
  	       APCH_STATUS_TEMPSTAT | APCH_STATUS_TIMRSTAT;
  	ret = regmap_write(regmap, ACT8945A_APCH_STATUS, ctrl);
  	if (ret)
  		return ret;
  
  	return 0;
  }
  
  static unsigned int act8945a_set_supply_type(struct act8945a_charger *charger,
  					     unsigned int *type)
  {
  	unsigned int status, state;
  	int ret;
  
  	ret = regmap_read(charger->regmap, ACT8945A_APCH_STATUS, &status);
  	if (ret < 0)
  		return ret;
  
  	ret = regmap_read(charger->regmap, ACT8945A_APCH_STATE, &state);
  	if (ret < 0)
  		return ret;
  
  	if (status & APCH_STATUS_INDAT) {
  		if (state & APCH_STATE_ACINSTAT)
  			*type = POWER_SUPPLY_TYPE_MAINS;
  		else
  			*type = POWER_SUPPLY_TYPE_USB;
  	} else {
  		*type = POWER_SUPPLY_TYPE_BATTERY;
  	}
  
  	return 0;
  }
  
  static void act8945a_work(struct work_struct *work)
  {
  	struct act8945a_charger *charger =
  			container_of(work, struct act8945a_charger, work);
  
  	act8945a_set_supply_type(charger, &charger->desc.type);
  
  	power_supply_changed(charger->psy);
  }
  
  static irqreturn_t act8945a_status_changed(int irq, void *dev_id)
  {
  	struct act8945a_charger *charger = dev_id;
  
  	if (charger->init_done)
  		schedule_work(&charger->work);
  
  	return IRQ_HANDLED;
  }
  
  #define DEFAULT_TOTAL_TIME_OUT		3
  #define DEFAULT_PRE_TIME_OUT		40
  #define DEFAULT_INPUT_OVP_THRESHOLD	6600
  
  static int act8945a_charger_config(struct device *dev,
  				   struct act8945a_charger *charger)
  {
  	struct device_node *np = dev->of_node;
  	struct regmap *regmap = charger->regmap;
  
  	u32 total_time_out;
  	u32 pre_time_out;
  	u32 input_voltage_threshold;
  	int err, ret;
  
  	unsigned int tmp;
  	unsigned int value = 0;
  
  	if (!np) {
  		dev_err(dev, "no charger of node\n");
  		return -EINVAL;
  	}
  
  	ret = regmap_read(regmap, ACT8945A_APCH_CFG, &tmp);
  	if (ret)
  		return ret;
  
  	if (tmp & APCH_CFG_SUSCHG) {
  		value |= APCH_CFG_SUSCHG;
  		dev_info(dev, "have been suspended\n");
  	}
  
  	charger->lbo_gpio = devm_gpiod_get_optional(dev, "active-semi,lbo",
  						    GPIOD_IN);
  	if (IS_ERR(charger->lbo_gpio)) {
  		err = PTR_ERR(charger->lbo_gpio);
  		dev_err(dev, "unable to claim gpio \"lbo\": %d\n", err);
  		return err;
  	}
  
  	ret = devm_request_irq(dev, gpiod_to_irq(charger->lbo_gpio),
  			       act8945a_status_changed,
  			       (IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING),
  			       "act8945a_lbo_detect", charger);
  	if (ret)
  		dev_info(dev, "failed to request gpio \"lbo\" IRQ\n");
  
  	charger->chglev_gpio = devm_gpiod_get_optional(dev,
  						       "active-semi,chglev",
  						       GPIOD_IN);
  	if (IS_ERR(charger->chglev_gpio)) {
  		err = PTR_ERR(charger->chglev_gpio);
  		dev_err(dev, "unable to claim gpio \"chglev\": %d\n", err);
  		return err;
  	}
  
  	if (of_property_read_u32(np,
  				 "active-semi,input-voltage-threshold-microvolt",
  				 &input_voltage_threshold))
  		input_voltage_threshold = DEFAULT_INPUT_OVP_THRESHOLD;
  
  	if (of_property_read_u32(np,
  				 "active-semi,precondition-timeout",
  				 &pre_time_out))
  		pre_time_out = DEFAULT_PRE_TIME_OUT;
  
  	if (of_property_read_u32(np, "active-semi,total-timeout",
  				 &total_time_out))
  		total_time_out = DEFAULT_TOTAL_TIME_OUT;
  
  	switch (input_voltage_threshold) {
  	case 8000:
  		value |= APCH_CFG_OVPSET_8V;
  		break;
  	case 7500:
  		value |= APCH_CFG_OVPSET_7V5;
  		break;
  	case 7000:
  		value |= APCH_CFG_OVPSET_7V;
  		break;
  	case 6600:
  	default:
  		value |= APCH_CFG_OVPSET_6V6;
  		break;
  	}
  
  	switch (pre_time_out) {
  	case 60:
  		value |= APCH_CFG_PRETIMO_60_MIN;
  		break;
  	case 80:
  		value |= APCH_CFG_PRETIMO_80_MIN;
  		break;
  	case 0:
  		value |= APCH_CFG_PRETIMO_DISABLED;
  		break;
  	case 40:
  	default:
  		value |= APCH_CFG_PRETIMO_40_MIN;
  		break;
  	}
  
  	switch (total_time_out) {
  	case 4:
  		value |= APCH_CFG_TOTTIMO_4_HOUR;
  		break;
  	case 5:
  		value |= APCH_CFG_TOTTIMO_5_HOUR;
  		break;
  	case 0:
  		value |= APCH_CFG_TOTTIMO_DISABLED;
  		break;
  	case 3:
  	default:
  		value |= APCH_CFG_TOTTIMO_3_HOUR;
  		break;
  	}
  
  	return regmap_write(regmap, ACT8945A_APCH_CFG, value);
  }
  
  static int act8945a_charger_probe(struct platform_device *pdev)
  {
  	struct act8945a_charger *charger;
  	struct power_supply_config psy_cfg = {};
  	int irq, ret;
  
  	charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
  	if (!charger)
  		return -ENOMEM;
  
  	charger->regmap = dev_get_regmap(pdev->dev.parent, NULL);
  	if (!charger->regmap) {
  		dev_err(&pdev->dev, "Parent did not provide regmap\n");
  		return -EINVAL;
  	}
  
  	ret = act8945a_charger_config(&pdev->dev, charger);
  	if (ret)
  		return ret;
  
  	irq = of_irq_get(pdev->dev.of_node, 0);
  	if (irq == -EPROBE_DEFER) {
  		dev_err(&pdev->dev, "failed to find IRQ number\n");
  		return -EPROBE_DEFER;
  	}
  
  	ret = devm_request_irq(&pdev->dev, irq, act8945a_status_changed,
  			       IRQF_TRIGGER_FALLING, "act8945a_interrupt",
  			       charger);
  	if (ret) {
  		dev_err(&pdev->dev, "failed to request nIRQ pin IRQ\n");
  		return ret;
  	}
  
  	charger->desc.name = "act8945a-charger";
  	charger->desc.get_property = act8945a_charger_get_property;
  	charger->desc.properties = act8945a_charger_props;
  	charger->desc.num_properties = ARRAY_SIZE(act8945a_charger_props);
  
  	ret = act8945a_set_supply_type(charger, &charger->desc.type);
  	if (ret)
  		return -EINVAL;
  
  	psy_cfg.of_node	= pdev->dev.of_node;
  	psy_cfg.drv_data = charger;
  
  	charger->psy = devm_power_supply_register(&pdev->dev,
  						  &charger->desc,
  						  &psy_cfg);
  	if (IS_ERR(charger->psy)) {
  		dev_err(&pdev->dev, "failed to register power supply\n");
  		return PTR_ERR(charger->psy);
  	}
  
  	platform_set_drvdata(pdev, charger);
  
  	INIT_WORK(&charger->work, act8945a_work);
  
  	ret = act8945a_enable_interrupt(charger);
  	if (ret)
  		return -EIO;
  
  	charger->init_done = true;
  
  	return 0;
  }
  
  static int act8945a_charger_remove(struct platform_device *pdev)
  {
  	struct act8945a_charger *charger = platform_get_drvdata(pdev);
  
  	charger->init_done = false;
  	cancel_work_sync(&charger->work);
  
  	return 0;
  }
  
  static struct platform_driver act8945a_charger_driver = {
  	.driver	= {
  		.name = "act8945a-charger",
  	},
  	.probe	= act8945a_charger_probe,
  	.remove = act8945a_charger_remove,
  };
  module_platform_driver(act8945a_charger_driver);
  
  MODULE_DESCRIPTION("Active-semi ACT8945A ActivePath charger driver");
  MODULE_AUTHOR("Wenyou Yang <wenyou.yang@atmel.com>");
  MODULE_LICENSE("GPL");
  