// SPDX-License-Identifier: GPL-2.0
//
// Copyright (C) 2021 Samuel Holland <samuel@sholland.org>

#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/power_supply.h>
#include <linux/regmap.h>

#define IP5XXX_BAT_TYPE_4_2V			0x0
#define IP5XXX_BAT_TYPE_4_3V			0x1
#define IP5XXX_BAT_TYPE_4_35V			0x2
#define IP5XXX_BAT_TYPE_4_4V			0x3
#define IP5XXX_CHG_STAT_IDLE			0x0
#define IP5XXX_CHG_STAT_TRICKLE		0x1
#define IP5XXX_CHG_STAT_CONST_VOLT		0x2
#define IP5XXX_CHG_STAT_CONST_CUR		0x3
#define IP5XXX_CHG_STAT_CONST_VOLT_STOP	0x4
#define IP5XXX_CHG_STAT_FULL			0x5
#define IP5XXX_CHG_STAT_TIMEOUT		0x6

struct ip5xxx {
	struct regmap *regmap;
	bool initialized;
	struct {
		struct {
			/* Charger enable */
			struct regmap_field *enable;
			/* Constant voltage value */
			struct regmap_field *const_volt_sel;
			/* Constant current value */
			struct regmap_field *const_curr_sel;
			/* Charger status */
			struct regmap_field *status;
			/* Charging ended flag */
			struct regmap_field *chg_end;
			/* Timeout flags (CV, charge, trickle) */
			struct regmap_field *timeout;
			/* Overvoltage limit */
			struct regmap_field *vin_overvolt;
		} charger;
		struct {
			/* Boost converter enable */
			struct regmap_field *enable;
			struct {
				/* Light load shutdown enable */
				struct regmap_field *enable;
				/* Light load shutdown current limit */
				struct regmap_field *i_limit;
			} light_load_shutdown;
			/* Automatic powerup on increased load */
			struct regmap_field *load_powerup_en;
			/* Automatic powerup on VIN pull-out */
			struct regmap_field *vin_pullout_en;
			/* Undervoltage limit */
			struct regmap_field *undervolt_limit;
			/* Light load status flag */
			struct regmap_field *light_load_status;
		} boost;
		struct {
			/* NTC disable */
			struct regmap_field *ntc_dis;
			/* Battery voltage type */
			struct regmap_field *type;
			/* Battery voltage autoset from Vset pin */
			struct regmap_field *vset_en;
			struct {
				/* Battery measurement registers */
				struct ip5xxx_battery_adc_regs {
					struct regmap_field *low;
					struct regmap_field *high;
				} volt, curr, open_volt;
			} adc;
		} battery;
		struct {
			/* Double/long press shutdown enable */
			struct regmap_field *shdn_enable;
			/* WLED activation: double press or long press */
			struct regmap_field *wled_mode;
			/* Shutdown activation: double press or long press */
			struct regmap_field *shdn_mode;
			/* Long press time */
			struct regmap_field *long_press_time;
			/* Button pressed */
			struct regmap_field *pressed;
			/* Button long-pressed */
			struct regmap_field *long_pressed;
			/* Button short-pressed */
			struct regmap_field *short_pressed;
		} btn;
		struct {
			/* WLED enable */
			struct regmap_field *enable;
			/* WLED detect */
			struct regmap_field *detect_en;
			/* WLED present */
			struct regmap_field *present;
		} wled;
	} regs;

	/* Maximum supported battery voltage (via regs.battery.type) */
	int vbat_max;
	/* Scaling constants for regs.boost.undervolt_limit */
	struct {
		int setpoint;
		int microvolts_per_bit;
	} boost_undervolt;
	/* Scaling constants for regs.charger.const_curr_sel */
	struct {
		int setpoint;
	} const_curr;
	/* Whether regs.charger.chg_end is inverted */
	u8 chg_end_inverted;
};

#define REG_FIELD_UNSUPPORTED { .lsb = 1 }
/* Register fields layout. Unsupported registers marked as { .lsb = 1 } */
struct ip5xxx_regfield_config {
	const struct reg_field charger_enable;
	const struct reg_field charger_const_volt_sel;
	const struct reg_field charger_const_curr_sel;
	const struct reg_field charger_status;
	const struct reg_field charger_chg_end;
	const struct reg_field charger_timeout;
	const struct reg_field charger_vin_overvolt;
	const struct reg_field boost_enable;
	const struct reg_field boost_llshdn_enable;
	const struct reg_field boost_llshdn_i_limit;
	const struct reg_field boost_load_powerup_en;
	const struct reg_field boost_vin_pullout_en;
	const struct reg_field boost_undervolt_limit;
	const struct reg_field boost_light_load_status;
	const struct reg_field battery_ntc_dis;
	const struct reg_field battery_type;
	const struct reg_field battery_vset_en;
	const struct reg_field battery_adc_volt_low;
	const struct reg_field battery_adc_volt_high;
	const struct reg_field battery_adc_curr_low;
	const struct reg_field battery_adc_curr_high;
	const struct reg_field battery_adc_ovolt_low;
	const struct reg_field battery_adc_ovolt_high;
	const struct reg_field btn_shdn_enable;
	const struct reg_field btn_wled_mode;
	const struct reg_field btn_shdn_mode;
	const struct reg_field btn_long_press_time;
	const struct reg_field btn_pressed;
	const struct reg_field btn_long_pressed;
	const struct reg_field btn_short_pressed;
	const struct reg_field wled_enable;
	const struct reg_field wled_detect_en;
	const struct reg_field wled_present;

	int vbat_max;
	int boost_undervolt_setpoint;
	int boost_undervolt_uv_per_bit;
	int const_curr_setpoint;
	u8  chg_end_inverted;
};

/*
 * The IP5xxx charger only responds on I2C when it is "awake". The charger is
 * generally only awake when VIN is powered or when its boost converter is
 * enabled. Going into shutdown resets all register values. To handle this:
 *  1) When any bus error occurs, assume the charger has gone into shutdown.
 *  2) Attempt the initialization sequence on each subsequent register access
 *     until it succeeds.
 */
static int ip5xxx_read(struct ip5xxx *ip5xxx, struct regmap_field *field,
		       unsigned int *val)
{
	int ret;

	if (!field)
		return -EOPNOTSUPP;

	ret = regmap_field_read(field, val);
	if (ret)
		ip5xxx->initialized = false;

	return ret;
}

static int ip5xxx_write(struct ip5xxx *ip5xxx, struct regmap_field *field,
			unsigned int val)
{
	int ret;

	if (!field)
		return -EOPNOTSUPP;

	ret = regmap_field_write(field, val);
	if (ret)
		ip5xxx->initialized = false;

	return ret;
}

static int ip5xxx_initialize(struct power_supply *psy)
{
	struct ip5xxx *ip5xxx = power_supply_get_drvdata(psy);
	int ret;

	if (ip5xxx->initialized)
		return 0;

	/*
	 * Disable shutdown under light load.
	 * Enable power on when under load.
	 */
	if (ip5xxx->regs.boost.light_load_shutdown.enable) {
		ret = ip5xxx_write(ip5xxx, ip5xxx->regs.boost.light_load_shutdown.enable, 0);
		if (ret)
			return ret;
	}
	ret = ip5xxx_write(ip5xxx, ip5xxx->regs.boost.load_powerup_en, 1);
	if (ret)
		return ret;

	/*
	 * Enable shutdown after a long button press (as configured below).
	 */
	ret = ip5xxx_write(ip5xxx, ip5xxx->regs.btn.shdn_enable, 1);
	if (ret)
		return ret;

	/*
	 * Power on automatically when VIN is removed.
	 */
	ret = ip5xxx_write(ip5xxx, ip5xxx->regs.boost.vin_pullout_en, 1);
	if (ret)
		return ret;

	/*
	 * Enable the NTC.
	 * Configure the button for two presses => LED, long press => shutdown.
	 */
	if (ip5xxx->regs.battery.ntc_dis) {
		ret = ip5xxx_write(ip5xxx, ip5xxx->regs.battery.ntc_dis, 0);
		if (ret)
			return ret;
	}
	ret = ip5xxx_write(ip5xxx, ip5xxx->regs.btn.wled_mode, 1);
	if (ret)
		return ret;
	ret = ip5xxx_write(ip5xxx, ip5xxx->regs.btn.shdn_mode, 1);
	if (ret)
		return ret;

	ip5xxx->initialized = true;
	dev_dbg(psy->dev.parent, "Initialized after power on\n");

	return 0;
}

static const enum power_supply_property ip5xxx_battery_properties[] = {
	POWER_SUPPLY_PROP_STATUS,
	POWER_SUPPLY_PROP_CHARGE_TYPE,
	POWER_SUPPLY_PROP_HEALTH,
	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_VOLTAGE_OCV,
	POWER_SUPPLY_PROP_CURRENT_NOW,
	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,
	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,
	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
};

static int ip5xxx_battery_get_status(struct ip5xxx *ip5xxx, int *val)
{
	unsigned int rval;
	int ret;

	if (!ip5xxx->regs.charger.status) {
		// Fall-back to Charging Ended bit
		ret = ip5xxx_read(ip5xxx, ip5xxx->regs.charger.chg_end, &rval);
		if (ret)
			return ret;

		if (rval == ip5xxx->chg_end_inverted)
			*val = POWER_SUPPLY_STATUS_CHARGING;
		else
			*val = POWER_SUPPLY_STATUS_NOT_CHARGING;
		return 0;
	}

	ret = ip5xxx_read(ip5xxx, ip5xxx->regs.charger.status, &rval);
	if (ret)
		return ret;

	switch (rval) {
	case IP5XXX_CHG_STAT_IDLE:
		*val = POWER_SUPPLY_STATUS_DISCHARGING;
		break;
	case IP5XXX_CHG_STAT_TRICKLE:
	case IP5XXX_CHG_STAT_CONST_CUR:
	case IP5XXX_CHG_STAT_CONST_VOLT:
		*val = POWER_SUPPLY_STATUS_CHARGING;
		break;
	case IP5XXX_CHG_STAT_CONST_VOLT_STOP:
	case IP5XXX_CHG_STAT_FULL:
		*val = POWER_SUPPLY_STATUS_FULL;
		break;
	case IP5XXX_CHG_STAT_TIMEOUT:
		*val = POWER_SUPPLY_STATUS_NOT_CHARGING;
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static int ip5xxx_battery_get_charge_type(struct ip5xxx *ip5xxx, int *val)
{
	unsigned int rval;
	int ret;

	ret = ip5xxx_read(ip5xxx, ip5xxx->regs.charger.status, &rval);
	if (ret)
		return ret;

	switch (rval) {
	case IP5XXX_CHG_STAT_IDLE:
	case IP5XXX_CHG_STAT_CONST_VOLT_STOP:
	case IP5XXX_CHG_STAT_FULL:
	case IP5XXX_CHG_STAT_TIMEOUT:
		*val = POWER_SUPPLY_CHARGE_TYPE_NONE;
		break;
	case IP5XXX_CHG_STAT_TRICKLE:
		*val = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
		break;
	case IP5XXX_CHG_STAT_CONST_CUR:
	case IP5XXX_CHG_STAT_CONST_VOLT:
		*val = POWER_SUPPLY_CHARGE_TYPE_STANDARD;
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static int ip5xxx_battery_get_health(struct ip5xxx *ip5xxx, int *val)
{
	unsigned int rval;
	int ret;

	ret = ip5xxx_read(ip5xxx, ip5xxx->regs.charger.timeout, &rval);
	if (ret)
		return ret;

	if (rval)
		*val = POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE;
	else
		*val = POWER_SUPPLY_HEALTH_GOOD;

	return 0;
}

static int ip5xxx_battery_get_voltage_max(struct ip5xxx *ip5xxx, int *val)
{
	unsigned int rval;
	int ret;

	ret = ip5xxx_read(ip5xxx, ip5xxx->regs.battery.type, &rval);
	if (ret)
		return ret;

	/*
	 * It is not clear what this will return if
	 * IP5XXX_CHG_CTL4_BAT_TYPE_SEL_EN is not set...
	 */
	switch (rval) {
	case IP5XXX_BAT_TYPE_4_2V:
		*val = 4200000;
		break;
	case IP5XXX_BAT_TYPE_4_3V:
		*val = 4300000;
		break;
	case IP5XXX_BAT_TYPE_4_35V:
		*val = 4350000;
		break;
	case IP5XXX_BAT_TYPE_4_4V:
		*val = 4400000;
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static int ip5xxx_battery_read_adc(struct ip5xxx *ip5xxx,
				   struct ip5xxx_battery_adc_regs *regs, int *val)
{
	unsigned int hi, lo;
	int ret;

	ret = ip5xxx_read(ip5xxx, regs->low, &lo);
	if (ret)
		return ret;

	ret = ip5xxx_read(ip5xxx, regs->high, &hi);
	if (ret)
		return ret;

	*val = sign_extend32(hi << 8 | lo, 13);

	return 0;
}

static int ip5xxx_battery_get_property(struct power_supply *psy,
				       enum power_supply_property psp,
				       union power_supply_propval *val)
{
	struct ip5xxx *ip5xxx = power_supply_get_drvdata(psy);
	int raw, ret, vmax;
	unsigned int rval;

	ret = ip5xxx_initialize(psy);
	if (ret)
		return ret;

	switch (psp) {
	case POWER_SUPPLY_PROP_STATUS:
		return ip5xxx_battery_get_status(ip5xxx, &val->intval);

	case POWER_SUPPLY_PROP_CHARGE_TYPE:
		return ip5xxx_battery_get_charge_type(ip5xxx, &val->intval);

	case POWER_SUPPLY_PROP_HEALTH:
		return ip5xxx_battery_get_health(ip5xxx, &val->intval);

	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
		return ip5xxx_battery_get_voltage_max(ip5xxx, &val->intval);

	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		ret = ip5xxx_battery_read_adc(ip5xxx, &ip5xxx->regs.battery.adc.volt, &raw);
		if (ret)
			return ret;

		val->intval = 2600000 + DIV_ROUND_CLOSEST(raw * 26855, 100);
		return 0;

	case POWER_SUPPLY_PROP_VOLTAGE_OCV:
		ret = ip5xxx_battery_read_adc(ip5xxx, &ip5xxx->regs.battery.adc.open_volt, &raw);
		if (ret)
			return ret;

		val->intval = 2600000 + DIV_ROUND_CLOSEST(raw * 26855, 100);
		return 0;

	case POWER_SUPPLY_PROP_CURRENT_NOW:
		ret = ip5xxx_battery_read_adc(ip5xxx, &ip5xxx->regs.battery.adc.curr, &raw);
		if (ret)
			return ret;

		val->intval = DIV_ROUND_CLOSEST(raw * 149197, 200);
		return 0;

	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
		ret = ip5xxx_read(ip5xxx, ip5xxx->regs.charger.const_curr_sel, &rval);
		if (ret)
			return ret;

		val->intval = ip5xxx->const_curr.setpoint + 100000 * rval;
		return 0;

	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
		val->intval = 100000 * 0x1f;
		return 0;

	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
		ret = ip5xxx_battery_get_voltage_max(ip5xxx, &vmax);
		if (ret)
			return ret;

		ret = ip5xxx_read(ip5xxx, ip5xxx->regs.charger.const_volt_sel, &rval);
		if (ret)
			return ret;

		val->intval = vmax + 14000 * rval;
		return 0;

	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
		ret = ip5xxx_battery_get_voltage_max(ip5xxx, &vmax);
		if (ret)
			return ret;

		val->intval = vmax + 14000 * 3;
		return 0;

	default:
		return -EINVAL;
	}
}

static int ip5xxx_battery_set_voltage_max(struct ip5xxx *ip5xxx, int val)
{
	unsigned int rval;
	int ret;

	if (val > ip5xxx->vbat_max)
		return -EINVAL;

	switch (val) {
	case 4200000:
		rval = IP5XXX_BAT_TYPE_4_2V;
		break;
	case 4300000:
		rval = IP5XXX_BAT_TYPE_4_3V;
		break;
	case 4350000:
		rval = IP5XXX_BAT_TYPE_4_35V;
		break;
	case 4400000:
		rval = IP5XXX_BAT_TYPE_4_4V;
		break;
	default:
		return -EINVAL;
	}

	ret = ip5xxx_write(ip5xxx, ip5xxx->regs.battery.type, rval);
	if (ret)
		return ret;

	/* Don't try to auto-detect battery type, even if the IC could */
	if (ip5xxx->regs.battery.vset_en) {
		ret = ip5xxx_write(ip5xxx, ip5xxx->regs.battery.vset_en, 1);
		if (ret)
			return ret;
	}

	return 0;
}

static int ip5xxx_battery_set_property(struct power_supply *psy,
				       enum power_supply_property psp,
				       const union power_supply_propval *val)
{
	struct ip5xxx *ip5xxx = power_supply_get_drvdata(psy);
	unsigned int rval;
	int ret, vmax;

	ret = ip5xxx_initialize(psy);
	if (ret)
		return ret;

	switch (psp) {
	case POWER_SUPPLY_PROP_STATUS:
		switch (val->intval) {
		case POWER_SUPPLY_STATUS_CHARGING:
			rval = 1;
			break;
		case POWER_SUPPLY_STATUS_DISCHARGING:
		case POWER_SUPPLY_STATUS_NOT_CHARGING:
			rval = 0;
			break;
		default:
			return -EINVAL;
		}
		return ip5xxx_write(ip5xxx, ip5xxx->regs.charger.enable, rval);

	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
		return ip5xxx_battery_set_voltage_max(ip5xxx, val->intval);

	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
		rval = (val->intval - ip5xxx->const_curr.setpoint) / 100000;
		return ip5xxx_write(ip5xxx, ip5xxx->regs.charger.const_curr_sel, rval);

	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
		ret = ip5xxx_battery_get_voltage_max(ip5xxx, &vmax);
		if (ret)
			return ret;

		rval = (val->intval - vmax) / 14000;
		return ip5xxx_write(ip5xxx, ip5xxx->regs.charger.const_volt_sel, rval);

	default:
		return -EINVAL;
	}
}

static int ip5xxx_battery_property_is_writeable(struct power_supply *psy,
						enum power_supply_property psp)
{
	return psp == POWER_SUPPLY_PROP_STATUS ||
	       psp == POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN ||
	       psp == POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT ||
	       psp == POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE;
}

static const struct power_supply_desc ip5xxx_battery_desc = {
	.name			= "ip5xxx-battery",
	.type			= POWER_SUPPLY_TYPE_BATTERY,
	.properties		= ip5xxx_battery_properties,
	.num_properties		= ARRAY_SIZE(ip5xxx_battery_properties),
	.get_property		= ip5xxx_battery_get_property,
	.set_property		= ip5xxx_battery_set_property,
	.property_is_writeable	= ip5xxx_battery_property_is_writeable,
};

static const enum power_supply_property ip5xxx_boost_properties[] = {
	POWER_SUPPLY_PROP_ONLINE,
	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
};

static int ip5xxx_boost_get_property(struct power_supply *psy,
				     enum power_supply_property psp,
				     union power_supply_propval *val)
{
	struct ip5xxx *ip5xxx = power_supply_get_drvdata(psy);
	unsigned int rval;
	int ret;

	ret = ip5xxx_initialize(psy);
	if (ret)
		return ret;

	switch (psp) {
	case POWER_SUPPLY_PROP_ONLINE:
		ret = ip5xxx_read(ip5xxx, ip5xxx->regs.boost.enable, &rval);
		if (ret)
			return ret;

		val->intval = !!rval;
		return 0;

	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
		ret = ip5xxx_read(ip5xxx, ip5xxx->regs.boost.undervolt_limit, &rval);
		if (ret)
			return ret;

		val->intval = ip5xxx->boost_undervolt.setpoint +
			      ip5xxx->boost_undervolt.microvolts_per_bit * rval;
		return 0;

	default:
		return -EINVAL;
	}
}

static int ip5xxx_boost_set_property(struct power_supply *psy,
				     enum power_supply_property psp,
				     const union power_supply_propval *val)
{
	struct ip5xxx *ip5xxx = power_supply_get_drvdata(psy);
	unsigned int rval;
	int ret;

	ret = ip5xxx_initialize(psy);
	if (ret)
		return ret;

	switch (psp) {
	case POWER_SUPPLY_PROP_ONLINE:
		return ip5xxx_write(ip5xxx, ip5xxx->regs.boost.enable, !!val->intval);

	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
		rval = (val->intval - ip5xxx->boost_undervolt.setpoint) /
			ip5xxx->boost_undervolt.microvolts_per_bit;
		return ip5xxx_write(ip5xxx, ip5xxx->regs.boost.undervolt_limit, rval);

	default:
		return -EINVAL;
	}
}

static int ip5xxx_boost_property_is_writeable(struct power_supply *psy,
					      enum power_supply_property psp)
{
	return true;
}

static const struct power_supply_desc ip5xxx_boost_desc = {
	.name			= "ip5xxx-boost",
	.type			= POWER_SUPPLY_TYPE_USB,
	.properties		= ip5xxx_boost_properties,
	.num_properties		= ARRAY_SIZE(ip5xxx_boost_properties),
	.get_property		= ip5xxx_boost_get_property,
	.set_property		= ip5xxx_boost_set_property,
	.property_is_writeable	= ip5xxx_boost_property_is_writeable,
};

static const struct regmap_config ip5xxx_regmap_config = {
	.reg_bits		= 8,
	.val_bits		= 8,
	.max_register		= 0xa9,
};

static struct ip5xxx_regfield_config ip51xx_fields = {
	.charger_enable = REG_FIELD(0x01, 1, 1),
	.charger_const_volt_sel = REG_FIELD(0x24, 1, 2),
	.charger_const_curr_sel = REG_FIELD(0x25, 0, 4),
	.charger_status = REG_FIELD(0x71, 5, 7),
	.charger_chg_end = REG_FIELD(0x71, 3, 3),
	.charger_timeout = REG_FIELD(0x71, 0, 2),
	.charger_vin_overvolt = REG_FIELD(0x72, 5, 5),
	.boost_enable = REG_FIELD(0x01, 2, 2),
	.boost_llshdn_enable = REG_FIELD(0x02, 1, 1),
	.boost_llshdn_i_limit = REG_FIELD(0x0c, 3, 7),
	.boost_load_powerup_en = REG_FIELD(0x02, 0, 0),
	.boost_vin_pullout_en = REG_FIELD(0x04, 5, 5),
	.boost_undervolt_limit = REG_FIELD(0x22, 2, 3),
	.boost_light_load_status = REG_FIELD(0x72, 6, 6),
	.battery_ntc_dis = REG_FIELD(0x07, 6, 6),
	.battery_type = REG_FIELD(0x24, 5, 6),
	.battery_vset_en = REG_FIELD(0x26, 6, 6),
	.battery_adc_volt_low = REG_FIELD(0xa2, 0, 7),
	.battery_adc_volt_high = REG_FIELD(0xa3, 0, 5),
	.battery_adc_curr_low = REG_FIELD(0xa4, 0, 7),
	.battery_adc_curr_high = REG_FIELD(0xa5, 0, 5),
	.battery_adc_ovolt_low = REG_FIELD(0xa8, 0, 7),
	.battery_adc_ovolt_high = REG_FIELD(0xa9, 0, 5),
	.btn_shdn_enable = REG_FIELD(0x03, 5, 5),
	.btn_wled_mode = REG_FIELD(0x07, 1, 1),
	.btn_shdn_mode = REG_FIELD(0x07, 0, 0),
	.btn_long_press_time = REG_FIELD(0x03, 6, 7),
	.btn_pressed = REG_FIELD(0x77, 3, 3),
	.btn_long_pressed = REG_FIELD(0x77, 1, 1),
	.btn_short_pressed = REG_FIELD(0x77, 0, 0),
	.wled_enable = REG_FIELD(0x01, 3, 3),
	.wled_detect_en = REG_FIELD(0x01, 4, 4),
	.wled_present = REG_FIELD(0x72, 7, 7),

	.vbat_max = 4350000,
	.boost_undervolt_setpoint = 4530000,
	.boost_undervolt_uv_per_bit = 100000,
};

static struct ip5xxx_regfield_config ip5306_fields = {
	.charger_enable = REG_FIELD(0x00, 4, 4),
	.charger_const_volt_sel = REG_FIELD(0x22, 0, 1),
	.charger_const_curr_sel = REG_FIELD(0x24, 0, 4),
	.charger_status = REG_FIELD_UNSUPPORTED, // other bits...
	.charger_chg_end = REG_FIELD(0x71, 3, 3),
	.charger_timeout = REG_FIELD_UNSUPPORTED,
	.charger_vin_overvolt = REG_FIELD_UNSUPPORTED,
	.boost_enable = REG_FIELD(0x00, 5, 5),
	.boost_llshdn_enable = REG_FIELD_UNSUPPORTED,
	.boost_llshdn_i_limit = REG_FIELD_UNSUPPORTED,
	.boost_load_powerup_en = REG_FIELD(0x00, 2, 2),
	.boost_vin_pullout_en = REG_FIELD(0x01, 2, 2),
	.boost_undervolt_limit = REG_FIELD(0x21, 2, 4),
	.boost_light_load_status = REG_FIELD(0x72, 2, 2),
	.battery_ntc_dis = REG_FIELD_UNSUPPORTED,
	.battery_type = REG_FIELD(0x22, 2, 3),
	.battery_vset_en = REG_FIELD_UNSUPPORTED,
	.battery_adc_volt_low = REG_FIELD_UNSUPPORTED,
	.battery_adc_volt_high = REG_FIELD_UNSUPPORTED,
	.battery_adc_curr_low = REG_FIELD_UNSUPPORTED,
	.battery_adc_curr_high = REG_FIELD_UNSUPPORTED,
	.battery_adc_ovolt_low = REG_FIELD_UNSUPPORTED,
	.battery_adc_ovolt_high = REG_FIELD_UNSUPPORTED,
	.btn_shdn_enable = REG_FIELD(0x00, 0, 0),
	.btn_wled_mode = REG_FIELD(0x01, 6, 6),
	.btn_shdn_mode = REG_FIELD(0x01, 7, 7),
	.btn_long_press_time = REG_FIELD(0x02, 4, 4), // +1s
	.btn_pressed = REG_FIELD_UNSUPPORTED,
	/* TODO: double press */
	.btn_long_pressed = REG_FIELD(0x77, 1, 1),
	.btn_short_pressed = REG_FIELD(0x77, 0, 0),
	.wled_enable = REG_FIELD_UNSUPPORTED,
	.wled_detect_en = REG_FIELD_UNSUPPORTED,
	.wled_present = REG_FIELD_UNSUPPORTED,

	.vbat_max = 4400000,
	.boost_undervolt_setpoint = 4450000,
	.boost_undervolt_uv_per_bit = 50000,
	.const_curr_setpoint = 50000,
	.chg_end_inverted = 1,
};

#define ip5xxx_setup_reg(_field, _reg) \
			do { \
				if (likely(cfg->_field.lsb <= cfg->_field.msb)) { \
					struct regmap_field *_tmp = devm_regmap_field_alloc(dev, \
							ip5xxx->regmap, cfg->_field); \
					if (!IS_ERR(_tmp)) \
						ip5xxx->regs._reg = _tmp; \
				} \
			} while (0)

static void ip5xxx_setup_regs(struct device *dev, struct ip5xxx *ip5xxx,
			      const struct ip5xxx_regfield_config *cfg)
{
	ip5xxx_setup_reg(charger_enable, charger.enable);
	ip5xxx_setup_reg(charger_const_volt_sel, charger.const_volt_sel);
	ip5xxx_setup_reg(charger_const_curr_sel, charger.const_curr_sel);
	ip5xxx_setup_reg(charger_status, charger.status);
	ip5xxx_setup_reg(charger_chg_end, charger.chg_end);
	ip5xxx_setup_reg(charger_timeout, charger.timeout);
	ip5xxx_setup_reg(charger_vin_overvolt, charger.vin_overvolt);
	ip5xxx_setup_reg(boost_enable, boost.enable);
	ip5xxx_setup_reg(boost_llshdn_enable, boost.light_load_shutdown.enable);
	ip5xxx_setup_reg(boost_llshdn_i_limit, boost.light_load_shutdown.i_limit);
	ip5xxx_setup_reg(boost_load_powerup_en, boost.load_powerup_en);
	ip5xxx_setup_reg(boost_vin_pullout_en, boost.vin_pullout_en);
	ip5xxx_setup_reg(boost_undervolt_limit, boost.undervolt_limit);
	ip5xxx_setup_reg(boost_light_load_status, boost.light_load_status);
	ip5xxx_setup_reg(battery_ntc_dis, battery.ntc_dis);
	ip5xxx_setup_reg(battery_type, battery.type);
	ip5xxx_setup_reg(battery_vset_en, battery.vset_en);
	ip5xxx_setup_reg(battery_adc_volt_low, battery.adc.volt.low);
	ip5xxx_setup_reg(battery_adc_volt_high, battery.adc.volt.high);
	ip5xxx_setup_reg(battery_adc_curr_low, battery.adc.curr.low);
	ip5xxx_setup_reg(battery_adc_curr_high, battery.adc.curr.high);
	ip5xxx_setup_reg(battery_adc_ovolt_low, battery.adc.open_volt.low);
	ip5xxx_setup_reg(battery_adc_ovolt_high, battery.adc.open_volt.high);
	ip5xxx_setup_reg(btn_shdn_enable, btn.shdn_enable);
	ip5xxx_setup_reg(btn_wled_mode, btn.wled_mode);
	ip5xxx_setup_reg(btn_shdn_mode, btn.shdn_mode);
	ip5xxx_setup_reg(btn_long_press_time, btn.long_press_time);
	ip5xxx_setup_reg(btn_pressed, btn.pressed);
	ip5xxx_setup_reg(btn_long_pressed, btn.long_pressed);
	ip5xxx_setup_reg(btn_short_pressed, btn.short_pressed);
	ip5xxx_setup_reg(wled_enable, wled.enable);
	ip5xxx_setup_reg(wled_detect_en, wled.detect_en);
	ip5xxx_setup_reg(wled_present, wled.present);

	ip5xxx->vbat_max = cfg->vbat_max;
	ip5xxx->boost_undervolt.setpoint = cfg->boost_undervolt_setpoint;
	ip5xxx->boost_undervolt.microvolts_per_bit = cfg->boost_undervolt_uv_per_bit;
	ip5xxx->const_curr.setpoint = cfg->const_curr_setpoint;
	ip5xxx->chg_end_inverted = cfg->chg_end_inverted;
}

static int ip5xxx_power_probe(struct i2c_client *client)
{
	const struct ip5xxx_regfield_config *fields = &ip51xx_fields;
	struct power_supply_config psy_cfg = {};
	struct device *dev = &client->dev;
	const struct of_device_id *of_id;
	struct power_supply *psy;
	struct ip5xxx *ip5xxx;

	ip5xxx = devm_kzalloc(dev, sizeof(*ip5xxx), GFP_KERNEL);
	if (!ip5xxx)
		return -ENOMEM;

	ip5xxx->regmap = devm_regmap_init_i2c(client, &ip5xxx_regmap_config);
	if (IS_ERR(ip5xxx->regmap))
		return PTR_ERR(ip5xxx->regmap);

	of_id = i2c_of_match_device(dev->driver->of_match_table, client);
	if (of_id)
		fields = (const struct ip5xxx_regfield_config *)of_id->data;
	ip5xxx_setup_regs(dev, ip5xxx, fields);

	psy_cfg.of_node = dev->of_node;
	psy_cfg.drv_data = ip5xxx;

	psy = devm_power_supply_register(dev, &ip5xxx_battery_desc, &psy_cfg);
	if (IS_ERR(psy))
		return PTR_ERR(psy);

	psy = devm_power_supply_register(dev, &ip5xxx_boost_desc, &psy_cfg);
	if (IS_ERR(psy))
		return PTR_ERR(psy);

	return 0;
}

static const struct of_device_id ip5xxx_power_of_match[] = {
	{ .compatible = "injoinic,ip5108", .data = &ip51xx_fields },
	{ .compatible = "injoinic,ip5109", .data = &ip51xx_fields },
	{ .compatible = "injoinic,ip5207", .data = &ip51xx_fields },
	{ .compatible = "injoinic,ip5209", .data = &ip51xx_fields },
	{ .compatible = "injoinic,ip5306", .data = &ip5306_fields },
	{ }
};
MODULE_DEVICE_TABLE(of, ip5xxx_power_of_match);

static struct i2c_driver ip5xxx_power_driver = {
	.probe		= ip5xxx_power_probe,
	.driver		= {
		.name		= "ip5xxx-power",
		.of_match_table	= ip5xxx_power_of_match,
	}
};
module_i2c_driver(ip5xxx_power_driver);

MODULE_AUTHOR("Samuel Holland <samuel@sholland.org>");
MODULE_DESCRIPTION("Injoinic IP5xxx power bank IC driver");
MODULE_LICENSE("GPL");