// SPDX-License-Identifier: GPL-2.0-only
/*
 * Summit Microelectronics SMB347 Battery Charger Driver
 *
 * Copyright (C) 2011, Intel Corporation
 *
 * Authors: Bruce E. Robertson <bruce.e.robertson@intel.com>
 *          Mika Westerberg <mika.westerberg@linux.intel.com>
 */

#include <linux/delay.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/power_supply.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>

#include <dt-bindings/power/summit,smb347-charger.h>

/* Use the default compensation method */
#define SMB3XX_SOFT_TEMP_COMPENSATE_DEFAULT -1

/* Use default factory programmed value for hard/soft temperature limit */
#define SMB3XX_TEMP_USE_DEFAULT         -273

/*
 * Configuration registers. These are mirrored to volatile RAM and can be
 * written once %CMD_A_ALLOW_WRITE is set in %CMD_A register. They will be
 * reloaded from non-volatile registers after POR.
 */
#define CFG_CHARGE_CURRENT                      0x00
#define CFG_CHARGE_CURRENT_FCC_MASK             0xe0
#define CFG_CHARGE_CURRENT_FCC_SHIFT            5
#define CFG_CHARGE_CURRENT_PCC_MASK             0x18
#define CFG_CHARGE_CURRENT_PCC_SHIFT            3
#define CFG_CHARGE_CURRENT_TC_MASK              0x07
#define CFG_CURRENT_LIMIT                       0x01
#define CFG_CURRENT_LIMIT_DC_MASK               0xf0
#define CFG_CURRENT_LIMIT_DC_SHIFT              4
#define CFG_CURRENT_LIMIT_USB_MASK              0x0f
#define CFG_FLOAT_VOLTAGE                       0x03
#define CFG_FLOAT_VOLTAGE_FLOAT_MASK            0x3f
#define CFG_FLOAT_VOLTAGE_THRESHOLD_MASK        0xc0
#define CFG_FLOAT_VOLTAGE_THRESHOLD_SHIFT       6
#define CFG_STAT                                0x05
#define CFG_STAT_DISABLED                       BIT(5)
#define CFG_STAT_ACTIVE_HIGH                    BIT(7)
#define CFG_PIN                                 0x06
#define CFG_PIN_EN_CTRL_MASK                    0x60
#define CFG_PIN_EN_CTRL_ACTIVE_HIGH             0x40
#define CFG_PIN_EN_CTRL_ACTIVE_LOW              0x60
#define CFG_PIN_EN_APSD_IRQ                     BIT(1)
#define CFG_PIN_EN_CHARGER_ERROR                BIT(2)
#define CFG_PIN_EN_CTRL                         BIT(4)
#define CFG_THERM                               0x07
#define CFG_THERM_SOFT_HOT_COMPENSATION_MASK    0x03
#define CFG_THERM_SOFT_HOT_COMPENSATION_SHIFT   0
#define CFG_THERM_SOFT_COLD_COMPENSATION_MASK   0x0c
#define CFG_THERM_SOFT_COLD_COMPENSATION_SHIFT  2
#define CFG_THERM_MONITOR_DISABLED              BIT(4)
#define CFG_SYSOK                               0x08
#define CFG_SYSOK_INOK_ACTIVE_HIGH              BIT(0)
#define CFG_SYSOK_SUSPEND_HARD_LIMIT_DISABLED   BIT(2)
#define CFG_OTHER                               0x09
#define CFG_OTHER_RID_MASK                      0xc0
#define CFG_OTHER_RID_ENABLED_AUTO_OTG          0xc0
#define CFG_OTG                                 0x0a
#define CFG_OTG_TEMP_THRESHOLD_MASK             0x30
#define CFG_OTG_CURRENT_LIMIT_250mA             BIT(2)
#define CFG_OTG_CURRENT_LIMIT_750mA             BIT(3)
#define CFG_OTG_TEMP_THRESHOLD_SHIFT            4
#define CFG_OTG_CC_COMPENSATION_MASK            0xc0
#define CFG_OTG_CC_COMPENSATION_SHIFT           6
#define CFG_TEMP_LIMIT                          0x0b
#define CFG_TEMP_LIMIT_SOFT_HOT_MASK            0x03
#define CFG_TEMP_LIMIT_SOFT_HOT_SHIFT           0
#define CFG_TEMP_LIMIT_SOFT_COLD_MASK           0x0c
#define CFG_TEMP_LIMIT_SOFT_COLD_SHIFT          2
#define CFG_TEMP_LIMIT_HARD_HOT_MASK            0x30
#define CFG_TEMP_LIMIT_HARD_HOT_SHIFT           4
#define CFG_TEMP_LIMIT_HARD_COLD_MASK           0xc0
#define CFG_TEMP_LIMIT_HARD_COLD_SHIFT          6
#define CFG_FAULT_IRQ                           0x0c
#define CFG_FAULT_IRQ_DCIN_UV                   BIT(2)
#define CFG_STATUS_IRQ                          0x0d
#define CFG_STATUS_IRQ_TERMINATION_OR_TAPER     BIT(4)
#define CFG_STATUS_IRQ_CHARGE_TIMEOUT           BIT(7)
#define CFG_ADDRESS                             0x0e

/* Command registers */
#define CMD_A                                   0x30
#define CMD_A_CHG_ENABLED                       BIT(1)
#define CMD_A_SUSPEND_ENABLED                   BIT(2)
#define CMD_A_OTG_ENABLED                       BIT(4)
#define CMD_A_ALLOW_WRITE                       BIT(7)
#define CMD_B                                   0x31
#define CMD_C                                   0x33

/* Interrupt Status registers */
#define IRQSTAT_A                               0x35
#define IRQSTAT_C                               0x37
#define IRQSTAT_C_TERMINATION_STAT              BIT(0)
#define IRQSTAT_C_TERMINATION_IRQ               BIT(1)
#define IRQSTAT_C_TAPER_IRQ                     BIT(3)
#define IRQSTAT_D                               0x38
#define IRQSTAT_D_CHARGE_TIMEOUT_STAT           BIT(2)
#define IRQSTAT_D_CHARGE_TIMEOUT_IRQ            BIT(3)
#define IRQSTAT_E                               0x39
#define IRQSTAT_E_USBIN_UV_STAT                 BIT(0)
#define IRQSTAT_E_USBIN_UV_IRQ                  BIT(1)
#define IRQSTAT_E_DCIN_UV_STAT                  BIT(4)
#define IRQSTAT_E_DCIN_UV_IRQ                   BIT(5)
#define IRQSTAT_F                               0x3a

/* Status registers */
#define STAT_A                                  0x3b
#define STAT_A_FLOAT_VOLTAGE_MASK               0x3f
#define STAT_B                                  0x3c
#define STAT_C                                  0x3d
#define STAT_C_CHG_ENABLED                      BIT(0)
#define STAT_C_HOLDOFF_STAT                     BIT(3)
#define STAT_C_CHG_MASK                         0x06
#define STAT_C_CHG_SHIFT                        1
#define STAT_C_CHG_TERM                         BIT(5)
#define STAT_C_CHARGER_ERROR                    BIT(6)
#define STAT_E                                  0x3f

#define SMB347_MAX_REGISTER                     0x3f

/**
 * struct smb347_charger - smb347 charger instance
 * @dev: pointer to device
 * @regmap: pointer to driver regmap
 * @mains: power_supply instance for AC/DC power
 * @usb: power_supply instance for USB power
 * @usb_rdev: USB VBUS regulator device
 * @id: SMB charger ID
 * @mains_online: is AC/DC input connected
 * @usb_online: is USB input connected
 * @irq_unsupported: is interrupt unsupported by SMB hardware
 * @usb_vbus_enabled: is USB VBUS powered by SMB charger
 * @max_charge_current: maximum current (in uA) the battery can be charged
 * @max_charge_voltage: maximum voltage (in uV) the battery can be charged
 * @pre_charge_current: current (in uA) to use in pre-charging phase
 * @termination_current: current (in uA) used to determine when the
 *                       charging cycle terminates
 * @pre_to_fast_voltage: voltage (in uV) treshold used for transitioning to
 *                       pre-charge to fast charge mode
 * @mains_current_limit: maximum input current drawn from AC/DC input (in uA)
 * @usb_hc_current_limit: maximum input high current (in uA) drawn from USB
 *                        input
 * @chip_temp_threshold: die temperature where device starts limiting charge
 *                       current [%100 - %130] (in degree C)
 * @soft_cold_temp_limit: soft cold temperature limit [%0 - %15] (in degree C),
 *                        granularity is 5 deg C.
 * @soft_hot_temp_limit: soft hot temperature limit [%40 - %55] (in degree  C),
 *                       granularity is 5 deg C.
 * @hard_cold_temp_limit: hard cold temperature limit [%-5 - %10] (in degree C),
 *                        granularity is 5 deg C.
 * @hard_hot_temp_limit: hard hot temperature limit [%50 - %65] (in degree C),
 *                       granularity is 5 deg C.
 * @suspend_on_hard_temp_limit: suspend charging when hard limit is hit
 * @soft_temp_limit_compensation: compensation method when soft temperature
 *                                limit is hit
 * @charge_current_compensation: current (in uA) for charging compensation
 *                               current when temperature hits soft limits
 * @use_mains: AC/DC input can be used
 * @use_usb: USB input can be used
 * @use_usb_otg: USB OTG output can be used (not implemented yet)
 * @enable_control: how charging enable/disable is controlled
 *                  (driver/pin controls)
 * @inok_polarity: polarity of INOK signal which denotes presence of external
 *                 power supply
 *
 * @use_main, @use_usb, and @use_usb_otg are means to enable/disable
 * hardware support for these. This is useful when we want to have for
 * example OTG charging controlled via OTG transceiver driver and not by
 * the SMB347 hardware.
 *
 * Hard and soft temperature limit values are given as described in the
 * device data sheet and assuming NTC beta value is %3750. Even if this is
 * not the case, these values should be used. They can be mapped to the
 * corresponding NTC beta values with the help of table %2 in the data
 * sheet. So for example if NTC beta is %3375 and we want to program hard
 * hot limit to be %53 deg C, @hard_hot_temp_limit should be set to %50.
 *
 * If zero value is given in any of the current and voltage values, the
 * factory programmed default will be used. For soft/hard temperature
 * values, pass in %SMB3XX_TEMP_USE_DEFAULT instead.
 */
struct smb347_charger {
        struct device           *dev;
        struct regmap           *regmap;
        struct power_supply     *mains;
        struct power_supply     *usb;
        struct regulator_dev    *usb_rdev;
        unsigned int            id;
        bool                    mains_online;
        bool                    usb_online;
        bool                    irq_unsupported;
        bool                    usb_vbus_enabled;

        unsigned int            max_charge_current;
        unsigned int            max_charge_voltage;
        unsigned int            pre_charge_current;
        unsigned int            termination_current;
        unsigned int            pre_to_fast_voltage;
        unsigned int            mains_current_limit;
        unsigned int            usb_hc_current_limit;
        unsigned int            chip_temp_threshold;
        int                     soft_cold_temp_limit;
        int                     soft_hot_temp_limit;
        int                     hard_cold_temp_limit;
        int                     hard_hot_temp_limit;
        bool                    suspend_on_hard_temp_limit;
        unsigned int            soft_temp_limit_compensation;
        unsigned int            charge_current_compensation;
        bool                    use_mains;
        bool                    use_usb;
        bool                    use_usb_otg;
        unsigned int            enable_control;
        unsigned int            inok_polarity;
};

enum smb_charger_chipid {
        SMB345,
        SMB347,
        SMB358,
        NUM_CHIP_TYPES,
};

/* Fast charge current in uA */
static const unsigned int fcc_tbl[NUM_CHIP_TYPES][8] = {
        [SMB345] = {  200000,  450000,  600000,  900000,
                     1300000, 1500000, 1800000, 2000000 },
        [SMB347] = {  700000,  900000, 1200000, 1500000,
                     1800000, 2000000, 2200000, 2500000 },
        [SMB358] = {  200000,  450000,  600000,  900000,
                     1300000, 1500000, 1800000, 2000000 },
};
/* Pre-charge current in uA */
static const unsigned int pcc_tbl[NUM_CHIP_TYPES][4] = {
        [SMB345] = { 150000, 250000, 350000, 450000 },
        [SMB347] = { 100000, 150000, 200000, 250000 },
        [SMB358] = { 150000, 250000, 350000, 450000 },
};

/* Termination current in uA */
static const unsigned int tc_tbl[NUM_CHIP_TYPES][8] = {
        [SMB345] = {  30000,  40000,  60000,  80000,
                     100000, 125000, 150000, 200000 },
        [SMB347] = {  37500,  50000, 100000, 150000,
                     200000, 250000, 500000, 600000 },
        [SMB358] = {  30000,  40000,  60000,  80000,
                     100000, 125000, 150000, 200000 },
};

/* Input current limit in uA */
static const unsigned int icl_tbl[NUM_CHIP_TYPES][10] = {
        [SMB345] = {  300000,  500000,  700000, 1000000, 1500000,
                     1800000, 2000000, 2000000, 2000000, 2000000 },
        [SMB347] = {  300000,  500000,  700000,  900000, 1200000,
                     1500000, 1800000, 2000000, 2200000, 2500000 },
        [SMB358] = {  300000,  500000,  700000, 1000000, 1500000,
                     1800000, 2000000, 2000000, 2000000, 2000000 },
};

/* Charge current compensation in uA */
static const unsigned int ccc_tbl[NUM_CHIP_TYPES][4] = {
        [SMB345] = {  200000,  450000,  600000,  900000 },
        [SMB347] = {  250000,  700000,  900000, 1200000 },
        [SMB358] = {  200000,  450000,  600000,  900000 },
};

/* Convert register value to current using lookup table */
static int hw_to_current(const unsigned int *tbl, size_t size, unsigned int val)
{
        if (val >= size)
                return -EINVAL;
        return tbl[val];
}

/* Convert current to register value using lookup table */
static int current_to_hw(const unsigned int *tbl, size_t size, unsigned int val)
{
        size_t i;

        for (i = 0; i < size; i++)
                if (val < tbl[i])
                        break;
        return i > 0 ? i - 1 : -EINVAL;
}

/**
 * smb347_update_ps_status - refreshes the power source status
 * @smb: pointer to smb347 charger instance
 *
 * Function checks whether any power source is connected to the charger and
 * updates internal state accordingly. If there is a change to previous state
 * function returns %1, otherwise %0 and negative errno in case of errror.
 */
static int smb347_update_ps_status(struct smb347_charger *smb)
{
        bool usb = false;
        bool dc = false;
        unsigned int val;
        int ret;

        ret = regmap_read(smb->regmap, IRQSTAT_E, &val);
        if (ret < 0)
                return ret;

        /*
         * Dc and usb are set depending on whether they are enabled in
         * platform data _and_ whether corresponding undervoltage is set.
         */
        if (smb->use_mains)
                dc = !(val & IRQSTAT_E_DCIN_UV_STAT);
        if (smb->use_usb)
                usb = !(val & IRQSTAT_E_USBIN_UV_STAT);

        ret = smb->mains_online != dc || smb->usb_online != usb;
        smb->mains_online = dc;
        smb->usb_online = usb;

        return ret;
}

/*
 * smb347_is_ps_online - returns whether input power source is connected
 * @smb: pointer to smb347 charger instance
 *
 * Returns %true if input power source is connected. Note that this is
 * dependent on what platform has configured for usable power sources. For
 * example if USB is disabled, this will return %false even if the USB cable
 * is connected.
 */
static bool smb347_is_ps_online(struct smb347_charger *smb)
{
        return smb->usb_online || smb->mains_online;
}

/**
 * smb347_charging_status - returns status of charging
 * @smb: pointer to smb347 charger instance
 *
 * Function returns charging status. %0 means no charging is in progress,
 * %1 means pre-charging, %2 fast-charging and %3 taper-charging.
 */
static int smb347_charging_status(struct smb347_charger *smb)
{
        unsigned int val;
        int ret;

        if (!smb347_is_ps_online(smb))
                return 0;

        ret = regmap_read(smb->regmap, STAT_C, &val);
        if (ret < 0)
                return 0;

        return (val & STAT_C_CHG_MASK) >> STAT_C_CHG_SHIFT;
}

static int smb347_charging_set(struct smb347_charger *smb, bool enable)
{
        if (smb->enable_control != SMB3XX_CHG_ENABLE_SW) {
                dev_dbg(smb->dev, "charging enable/disable in SW disabled\n");
                return 0;
        }

        if (enable && smb->usb_vbus_enabled) {
                dev_dbg(smb->dev, "charging not enabled because USB is in host mode\n");
                return 0;
        }

        return regmap_update_bits(smb->regmap, CMD_A, CMD_A_CHG_ENABLED,
                                  enable ? CMD_A_CHG_ENABLED : 0);
}

static inline int smb347_charging_enable(struct smb347_charger *smb)
{
        return smb347_charging_set(smb, true);
}

static inline int smb347_charging_disable(struct smb347_charger *smb)
{
        return smb347_charging_set(smb, false);
}

static int smb347_start_stop_charging(struct smb347_charger *smb)
{
        int ret;

        /*
         * Depending on whether valid power source is connected or not, we
         * disable or enable the charging. We do it manually because it
         * depends on how the platform has configured the valid inputs.
         */
        if (smb347_is_ps_online(smb)) {
                ret = smb347_charging_enable(smb);
                if (ret < 0)
                        dev_err(smb->dev, "failed to enable charging\n");
        } else {
                ret = smb347_charging_disable(smb);
                if (ret < 0)
                        dev_err(smb->dev, "failed to disable charging\n");
        }

        return ret;
}

static int smb347_set_charge_current(struct smb347_charger *smb)
{
        unsigned int id = smb->id;
        int ret;

        if (smb->max_charge_current) {
                ret = current_to_hw(fcc_tbl[id], ARRAY_SIZE(fcc_tbl[id]),
                                    smb->max_charge_current);
                if (ret < 0)
                        return ret;

                ret = regmap_update_bits(smb->regmap, CFG_CHARGE_CURRENT,
                                         CFG_CHARGE_CURRENT_FCC_MASK,
                                         ret << CFG_CHARGE_CURRENT_FCC_SHIFT);
                if (ret < 0)
                        return ret;
        }

        if (smb->pre_charge_current) {
                ret = current_to_hw(pcc_tbl[id], ARRAY_SIZE(pcc_tbl[id]),
                                    smb->pre_charge_current);
                if (ret < 0)
                        return ret;

                ret = regmap_update_bits(smb->regmap, CFG_CHARGE_CURRENT,
                                         CFG_CHARGE_CURRENT_PCC_MASK,
                                         ret << CFG_CHARGE_CURRENT_PCC_SHIFT);
                if (ret < 0)
                        return ret;
        }

        if (smb->termination_current) {
                ret = current_to_hw(tc_tbl[id], ARRAY_SIZE(tc_tbl[id]),
                                    smb->termination_current);
                if (ret < 0)
                        return ret;

                ret = regmap_update_bits(smb->regmap, CFG_CHARGE_CURRENT,
                                         CFG_CHARGE_CURRENT_TC_MASK, ret);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

static int smb347_set_current_limits(struct smb347_charger *smb)
{
        unsigned int id = smb->id;
        int ret;

        if (smb->mains_current_limit) {
                ret = current_to_hw(icl_tbl[id], ARRAY_SIZE(icl_tbl[id]),
                                    smb->mains_current_limit);
                if (ret < 0)
                        return ret;

                ret = regmap_update_bits(smb->regmap, CFG_CURRENT_LIMIT,
                                         CFG_CURRENT_LIMIT_DC_MASK,
                                         ret << CFG_CURRENT_LIMIT_DC_SHIFT);
                if (ret < 0)
                        return ret;
        }

        if (smb->usb_hc_current_limit) {
                ret = current_to_hw(icl_tbl[id], ARRAY_SIZE(icl_tbl[id]),
                                    smb->usb_hc_current_limit);
                if (ret < 0)
                        return ret;

                ret = regmap_update_bits(smb->regmap, CFG_CURRENT_LIMIT,
                                         CFG_CURRENT_LIMIT_USB_MASK, ret);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

static int smb347_set_voltage_limits(struct smb347_charger *smb)
{
        int ret;

        if (smb->pre_to_fast_voltage) {
                ret = smb->pre_to_fast_voltage;

                /* uV */
                ret = clamp_val(ret, 2400000, 3000000) - 2400000;
                ret /= 200000;

                ret = regmap_update_bits(smb->regmap, CFG_FLOAT_VOLTAGE,
                                CFG_FLOAT_VOLTAGE_THRESHOLD_MASK,
                                ret << CFG_FLOAT_VOLTAGE_THRESHOLD_SHIFT);
                if (ret < 0)
                        return ret;
        }

        if (smb->max_charge_voltage) {
                ret = smb->max_charge_voltage;

                /* uV */
                ret = clamp_val(ret, 3500000, 4500000) - 3500000;
                ret /= 20000;

                ret = regmap_update_bits(smb->regmap, CFG_FLOAT_VOLTAGE,
                                         CFG_FLOAT_VOLTAGE_FLOAT_MASK, ret);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

static int smb347_set_temp_limits(struct smb347_charger *smb)
{
        unsigned int id = smb->id;
        bool enable_therm_monitor = false;
        int ret = 0;
        int val;

        if (smb->chip_temp_threshold) {
                val = smb->chip_temp_threshold;

                /* degree C */
                val = clamp_val(val, 100, 130) - 100;
                val /= 10;

                ret = regmap_update_bits(smb->regmap, CFG_OTG,
                                         CFG_OTG_TEMP_THRESHOLD_MASK,
                                         val << CFG_OTG_TEMP_THRESHOLD_SHIFT);
                if (ret < 0)
                        return ret;
        }

        if (smb->soft_cold_temp_limit != SMB3XX_TEMP_USE_DEFAULT) {
                val = smb->soft_cold_temp_limit;

                val = clamp_val(val, 0, 15);
                val /= 5;
                /* this goes from higher to lower so invert the value */
                val = ~val & 0x3;

                ret = regmap_update_bits(smb->regmap, CFG_TEMP_LIMIT,
                                         CFG_TEMP_LIMIT_SOFT_COLD_MASK,
                                         val << CFG_TEMP_LIMIT_SOFT_COLD_SHIFT);
                if (ret < 0)
                        return ret;

                enable_therm_monitor = true;
        }

        if (smb->soft_hot_temp_limit != SMB3XX_TEMP_USE_DEFAULT) {
                val = smb->soft_hot_temp_limit;

                val = clamp_val(val, 40, 55) - 40;
                val /= 5;

                ret = regmap_update_bits(smb->regmap, CFG_TEMP_LIMIT,
                                         CFG_TEMP_LIMIT_SOFT_HOT_MASK,
                                         val << CFG_TEMP_LIMIT_SOFT_HOT_SHIFT);
                if (ret < 0)
                        return ret;

                enable_therm_monitor = true;
        }

        if (smb->hard_cold_temp_limit != SMB3XX_TEMP_USE_DEFAULT) {
                val = smb->hard_cold_temp_limit;

                val = clamp_val(val, -5, 10) + 5;
                val /= 5;
                /* this goes from higher to lower so invert the value */
                val = ~val & 0x3;

                ret = regmap_update_bits(smb->regmap, CFG_TEMP_LIMIT,
                                         CFG_TEMP_LIMIT_HARD_COLD_MASK,
                                         val << CFG_TEMP_LIMIT_HARD_COLD_SHIFT);
                if (ret < 0)
                        return ret;

                enable_therm_monitor = true;
        }

        if (smb->hard_hot_temp_limit != SMB3XX_TEMP_USE_DEFAULT) {
                val = smb->hard_hot_temp_limit;

                val = clamp_val(val, 50, 65) - 50;
                val /= 5;

                ret = regmap_update_bits(smb->regmap, CFG_TEMP_LIMIT,
                                         CFG_TEMP_LIMIT_HARD_HOT_MASK,
                                         val << CFG_TEMP_LIMIT_HARD_HOT_SHIFT);
                if (ret < 0)
                        return ret;

                enable_therm_monitor = true;
        }

        /*
         * If any of the temperature limits are set, we also enable the
         * thermistor monitoring.
         *
         * When soft limits are hit, the device will start to compensate
         * current and/or voltage depending on the configuration.
         *
         * When hard limit is hit, the device will suspend charging
         * depending on the configuration.
         */
        if (enable_therm_monitor) {
                ret = regmap_update_bits(smb->regmap, CFG_THERM,
                                         CFG_THERM_MONITOR_DISABLED, 0);
                if (ret < 0)
                        return ret;
        }

        if (smb->suspend_on_hard_temp_limit) {
                ret = regmap_update_bits(smb->regmap, CFG_SYSOK,
                                 CFG_SYSOK_SUSPEND_HARD_LIMIT_DISABLED, 0);
                if (ret < 0)
                        return ret;
        }

        if (smb->soft_temp_limit_compensation !=
            SMB3XX_SOFT_TEMP_COMPENSATE_DEFAULT) {
                val = smb->soft_temp_limit_compensation & 0x3;

                ret = regmap_update_bits(smb->regmap, CFG_THERM,
                                 CFG_THERM_SOFT_HOT_COMPENSATION_MASK,
                                 val << CFG_THERM_SOFT_HOT_COMPENSATION_SHIFT);
                if (ret < 0)
                        return ret;

                ret = regmap_update_bits(smb->regmap, CFG_THERM,
                                 CFG_THERM_SOFT_COLD_COMPENSATION_MASK,
                                 val << CFG_THERM_SOFT_COLD_COMPENSATION_SHIFT);
                if (ret < 0)
                        return ret;
        }

        if (smb->charge_current_compensation) {
                val = current_to_hw(ccc_tbl[id], ARRAY_SIZE(ccc_tbl[id]),
                                    smb->charge_current_compensation);
                if (val < 0)
                        return val;

                ret = regmap_update_bits(smb->regmap, CFG_OTG,
                                CFG_OTG_CC_COMPENSATION_MASK,
                                (val & 0x3) << CFG_OTG_CC_COMPENSATION_SHIFT);
                if (ret < 0)
                        return ret;
        }

        return ret;
}

/*
 * smb347_set_writable - enables/disables writing to non-volatile registers
 * @smb: pointer to smb347 charger instance
 *
 * You can enable/disable writing to the non-volatile configuration
 * registers by calling this function.
 *
 * Returns %0 on success and negative errno in case of failure.
 */
static int smb347_set_writable(struct smb347_charger *smb, bool writable,
                               bool irq_toggle)
{
        struct i2c_client *client = to_i2c_client(smb->dev);
        int ret;

        if (writable && irq_toggle && !smb->irq_unsupported)
                disable_irq(client->irq);

        ret = regmap_update_bits(smb->regmap, CMD_A, CMD_A_ALLOW_WRITE,
                                 writable ? CMD_A_ALLOW_WRITE : 0);

        if ((!writable || ret) && irq_toggle && !smb->irq_unsupported)
                enable_irq(client->irq);

        return ret;
}

static int smb347_hw_init(struct smb347_charger *smb)
{
        unsigned int val;
        int ret;

        ret = smb347_set_writable(smb, true, false);
        if (ret < 0)
                return ret;

        /*
         * Program the platform specific configuration values to the device
         * first.
         */
        ret = smb347_set_charge_current(smb);
        if (ret < 0)
                goto fail;

        ret = smb347_set_current_limits(smb);
        if (ret < 0)
                goto fail;

        ret = smb347_set_voltage_limits(smb);
        if (ret < 0)
                goto fail;

        ret = smb347_set_temp_limits(smb);
        if (ret < 0)
                goto fail;

        /* If USB charging is disabled we put the USB in suspend mode */
        if (!smb->use_usb) {
                ret = regmap_update_bits(smb->regmap, CMD_A,
                                         CMD_A_SUSPEND_ENABLED,
                                         CMD_A_SUSPEND_ENABLED);
                if (ret < 0)
                        goto fail;
        }

        /*
         * If configured by platform data, we enable hardware Auto-OTG
         * support for driving VBUS. Otherwise we disable it.
         */
        ret = regmap_update_bits(smb->regmap, CFG_OTHER, CFG_OTHER_RID_MASK,
                smb->use_usb_otg ? CFG_OTHER_RID_ENABLED_AUTO_OTG : 0);
        if (ret < 0)
                goto fail;

        /* Activate pin control, making it writable. */
        switch (smb->enable_control) {
        case SMB3XX_CHG_ENABLE_PIN_ACTIVE_LOW:
        case SMB3XX_CHG_ENABLE_PIN_ACTIVE_HIGH:
                ret = regmap_set_bits(smb->regmap, CFG_PIN, CFG_PIN_EN_CTRL);
                if (ret < 0)
                        goto fail;
        }

        /*
         * Make the charging functionality controllable by a write to the
         * command register unless pin control is specified in the platform
         * data.
         */
        switch (smb->enable_control) {
        case SMB3XX_CHG_ENABLE_PIN_ACTIVE_LOW:
                val = CFG_PIN_EN_CTRL_ACTIVE_LOW;
                break;
        case SMB3XX_CHG_ENABLE_PIN_ACTIVE_HIGH:
                val = CFG_PIN_EN_CTRL_ACTIVE_HIGH;
                break;
        default:
                val = 0;
                break;
        }

        ret = regmap_update_bits(smb->regmap, CFG_PIN, CFG_PIN_EN_CTRL_MASK,
                                 val);
        if (ret < 0)
                goto fail;

        /* Disable Automatic Power Source Detection (APSD) interrupt. */
        ret = regmap_update_bits(smb->regmap, CFG_PIN, CFG_PIN_EN_APSD_IRQ, 0);
        if (ret < 0)
                goto fail;

        ret = smb347_update_ps_status(smb);
        if (ret < 0)
                goto fail;

        ret = smb347_start_stop_charging(smb);

fail:
        smb347_set_writable(smb, false, false);
        return ret;
}

static irqreturn_t smb347_interrupt(int irq, void *data)
{
        struct smb347_charger *smb = data;
        unsigned int stat_c, irqstat_c, irqstat_d, irqstat_e;
        bool handled = false;
        int ret;

        /* SMB347 it needs at least 20ms for setting IRQSTAT_E_*IN_UV_IRQ */
        usleep_range(25000, 35000);

        ret = regmap_read(smb->regmap, STAT_C, &stat_c);
        if (ret < 0) {
                dev_warn(smb->dev, "reading STAT_C failed\n");
                return IRQ_NONE;
        }

        ret = regmap_read(smb->regmap, IRQSTAT_C, &irqstat_c);
        if (ret < 0) {
                dev_warn(smb->dev, "reading IRQSTAT_C failed\n");
                return IRQ_NONE;
        }

        ret = regmap_read(smb->regmap, IRQSTAT_D, &irqstat_d);
        if (ret < 0) {
                dev_warn(smb->dev, "reading IRQSTAT_D failed\n");
                return IRQ_NONE;
        }

        ret = regmap_read(smb->regmap, IRQSTAT_E, &irqstat_e);
        if (ret < 0) {
                dev_warn(smb->dev, "reading IRQSTAT_E failed\n");
                return IRQ_NONE;
        }

        /*
         * If we get charger error we report the error back to user.
         * If the error is recovered charging will resume again.
         */
        if (stat_c & STAT_C_CHARGER_ERROR) {
                dev_err(smb->dev, "charging stopped due to charger error\n");
                if (smb->use_mains)
                        power_supply_changed(smb->mains);
                if (smb->use_usb)
                        power_supply_changed(smb->usb);
                handled = true;
        }

        /*
         * If we reached the termination current the battery is charged and
         * we can update the status now. Charging is automatically
         * disabled by the hardware.
         */
        if (irqstat_c & (IRQSTAT_C_TERMINATION_IRQ | IRQSTAT_C_TAPER_IRQ)) {
                if (irqstat_c & IRQSTAT_C_TERMINATION_STAT) {
                        if (smb->use_mains)
                                power_supply_changed(smb->mains);
                        if (smb->use_usb)
                                power_supply_changed(smb->usb);
                }
                dev_dbg(smb->dev, "going to HW maintenance mode\n");
                handled = true;
        }

        /*
         * If we got a charger timeout INT that means the charge
         * full is not detected with in charge timeout value.
         */
        if (irqstat_d & IRQSTAT_D_CHARGE_TIMEOUT_IRQ) {
                dev_dbg(smb->dev, "total Charge Timeout INT received\n");

                if (irqstat_d & IRQSTAT_D_CHARGE_TIMEOUT_STAT)
                        dev_warn(smb->dev, "charging stopped due to timeout\n");
                if (smb->use_mains)
                        power_supply_changed(smb->mains);
                if (smb->use_usb)
                        power_supply_changed(smb->usb);
                handled = true;
        }

        /*
         * If we got an under voltage interrupt it means that AC/USB input
         * was connected or disconnected.
         */
        if (irqstat_e & (IRQSTAT_E_USBIN_UV_IRQ | IRQSTAT_E_DCIN_UV_IRQ)) {
                if (smb347_update_ps_status(smb) > 0) {
                        smb347_start_stop_charging(smb);
                        if (smb->use_mains)
                                power_supply_changed(smb->mains);
                        if (smb->use_usb)
                                power_supply_changed(smb->usb);
                }
                handled = true;
        }

        return handled ? IRQ_HANDLED : IRQ_NONE;
}

static int smb347_irq_set(struct smb347_charger *smb, bool enable)
{
        int ret;

        if (smb->irq_unsupported)
                return 0;

        ret = smb347_set_writable(smb, true, true);
        if (ret < 0)
                return ret;

        /*
         * Enable/disable interrupts for:
         *      - under voltage
         *      - termination current reached
         *      - charger timeout
         *      - charger error
         */
        ret = regmap_update_bits(smb->regmap, CFG_FAULT_IRQ, 0xff,
                                 enable ? CFG_FAULT_IRQ_DCIN_UV : 0);
        if (ret < 0)
                goto fail;

        ret = regmap_update_bits(smb->regmap, CFG_STATUS_IRQ, 0xff,
                        enable ? (CFG_STATUS_IRQ_TERMINATION_OR_TAPER |
                                        CFG_STATUS_IRQ_CHARGE_TIMEOUT) : 0);
        if (ret < 0)
                goto fail;

        ret = regmap_update_bits(smb->regmap, CFG_PIN, CFG_PIN_EN_CHARGER_ERROR,
                                 enable ? CFG_PIN_EN_CHARGER_ERROR : 0);
fail:
        smb347_set_writable(smb, false, true);
        return ret;
}

static inline int smb347_irq_enable(struct smb347_charger *smb)
{
        return smb347_irq_set(smb, true);
}

static inline int smb347_irq_disable(struct smb347_charger *smb)
{
        return smb347_irq_set(smb, false);
}

static int smb347_irq_init(struct smb347_charger *smb,
                           struct i2c_client *client)
{
        int ret;

        smb->irq_unsupported = true;

        /*
         * Interrupt pin is optional. If it is connected, we setup the
         * interrupt support here.
         */
        if (!client->irq)
                return 0;

        ret = smb347_set_writable(smb, true, false);
        if (ret < 0)
                return ret;

        /*
         * Configure the STAT output to be suitable for interrupts: disable
         * all other output (except interrupts) and make it active low.
         */
        ret = regmap_update_bits(smb->regmap, CFG_STAT,
                                 CFG_STAT_ACTIVE_HIGH | CFG_STAT_DISABLED,
                                 CFG_STAT_DISABLED);

        smb347_set_writable(smb, false, false);

        if (ret < 0) {
                dev_warn(smb->dev, "failed to initialize IRQ: %d\n", ret);
                dev_warn(smb->dev, "disabling IRQ support\n");
                return 0;
        }

        ret = devm_request_threaded_irq(smb->dev, client->irq, NULL,
                                        smb347_interrupt, IRQF_ONESHOT,
                                        client->name, smb);
        if (ret)
                return ret;

        smb->irq_unsupported = false;

        ret = smb347_irq_enable(smb);
        if (ret < 0)
                return ret;

        return 0;
}

/*
 * Returns the constant charge current programmed
 * into the charger in uA.
 */
static int get_const_charge_current(struct smb347_charger *smb)
{
        unsigned int id = smb->id;
        int ret, intval;
        unsigned int v;

        if (!smb347_is_ps_online(smb))
                return -ENODATA;

        ret = regmap_read(smb->regmap, STAT_B, &v);
        if (ret < 0)

                return ret;

        /*
         * The current value is composition of FCC and PCC values
         * and we can detect which table to use from bit 5.
         */
        if (v & 0x20) {
                intval = hw_to_current(fcc_tbl[id],
                                       ARRAY_SIZE(fcc_tbl[id]), v & 7);
        } else {
                v >>= 3;
                intval = hw_to_current(pcc_tbl[id],
                                       ARRAY_SIZE(pcc_tbl[id]), v & 7);
        }

        return intval;
}

/*
 * Returns the constant charge voltage programmed
 * into the charger in uV.
 */
static int get_const_charge_voltage(struct smb347_charger *smb)
{
        int ret, intval;
        unsigned int v;

        if (!smb347_is_ps_online(smb))
                return -ENODATA;

        ret = regmap_read(smb->regmap, STAT_A, &v);
        if (ret < 0)
                return ret;

        v &= STAT_A_FLOAT_VOLTAGE_MASK;
        if (v > 0x3d)
                v = 0x3d;

        intval = 3500000 + v * 20000;

        return intval;
}

static int smb347_get_charging_status(struct smb347_charger *smb,
                                      struct power_supply *psy)
{
        int ret, status;
        unsigned int val;

        if (psy->desc->type == POWER_SUPPLY_TYPE_USB) {
                if (!smb->usb_online)
                        return POWER_SUPPLY_STATUS_DISCHARGING;
        } else {
                if (!smb->mains_online)
                        return POWER_SUPPLY_STATUS_DISCHARGING;
        }

        ret = regmap_read(smb->regmap, STAT_C, &val);
        if (ret < 0)
                return ret;

        if ((val & STAT_C_CHARGER_ERROR) ||
                        (val & STAT_C_HOLDOFF_STAT)) {
                /*
                 * set to NOT CHARGING upon charger error
                 * or charging has stopped.
                 */
                status = POWER_SUPPLY_STATUS_NOT_CHARGING;
        } else {
                if ((val & STAT_C_CHG_MASK) >> STAT_C_CHG_SHIFT) {
                        /*
                         * set to charging if battery is in pre-charge,
                         * fast charge or taper charging mode.
                         */
                        status = POWER_SUPPLY_STATUS_CHARGING;
                } else if (val & STAT_C_CHG_TERM) {
                        /*
                         * set the status to FULL if battery is not in pre
                         * charge, fast charge or taper charging mode AND
                         * charging is terminated at least once.
                         */
                        status = POWER_SUPPLY_STATUS_FULL;
                } else {
                        /*
                         * in this case no charger error or termination
                         * occured but charging is not in progress!!!
                         */
                        status = POWER_SUPPLY_STATUS_NOT_CHARGING;
                }
        }

        return status;
}

static int smb347_get_property_locked(struct power_supply *psy,
                                      enum power_supply_property prop,
                                      union power_supply_propval *val)
{
        struct smb347_charger *smb = power_supply_get_drvdata(psy);
        int ret;

        switch (prop) {
        case POWER_SUPPLY_PROP_STATUS:
                ret = smb347_get_charging_status(smb, psy);
                if (ret < 0)
                        return ret;
                val->intval = ret;
                break;

        case POWER_SUPPLY_PROP_CHARGE_TYPE:
                if (psy->desc->type == POWER_SUPPLY_TYPE_USB) {
                        if (!smb->usb_online)
                                return -ENODATA;
                } else {
                        if (!smb->mains_online)
                                return -ENODATA;
                }

                /*
                 * We handle trickle and pre-charging the same, and taper
                 * and none the same.
                 */
                switch (smb347_charging_status(smb)) {
                case 1:
                        val->intval = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
                        break;
                case 2:
                        val->intval = POWER_SUPPLY_CHARGE_TYPE_FAST;
                        break;
                default:
                        val->intval = POWER_SUPPLY_CHARGE_TYPE_NONE;
                        break;
                }
                break;

        case POWER_SUPPLY_PROP_ONLINE:
                if (psy->desc->type == POWER_SUPPLY_TYPE_USB)
                        val->intval = smb->usb_online;
                else
                        val->intval = smb->mains_online;
                break;

        case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
                ret = get_const_charge_voltage(smb);
                if (ret < 0)
                        return ret;
                val->intval = ret;
                break;

        case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
                ret = get_const_charge_current(smb);
                if (ret < 0)
                        return ret;
                val->intval = ret;
                break;

        default:
                return -EINVAL;
        }

        return 0;
}

static int smb347_get_property(struct power_supply *psy,
                               enum power_supply_property prop,
                               union power_supply_propval *val)
{
        struct smb347_charger *smb = power_supply_get_drvdata(psy);
        struct i2c_client *client = to_i2c_client(smb->dev);
        int ret;

        if (!smb->irq_unsupported)
                disable_irq(client->irq);

        ret = smb347_get_property_locked(psy, prop, val);

        if (!smb->irq_unsupported)
                enable_irq(client->irq);

        return ret;
}

static enum power_supply_property smb347_properties[] = {
        POWER_SUPPLY_PROP_STATUS,
        POWER_SUPPLY_PROP_CHARGE_TYPE,
        POWER_SUPPLY_PROP_ONLINE,
        POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,
        POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,
};

static bool smb347_volatile_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case IRQSTAT_A:
        case IRQSTAT_C:
        case IRQSTAT_D:
        case IRQSTAT_E:
        case IRQSTAT_F:
        case STAT_A:
        case STAT_B:
        case STAT_C:
        case STAT_E:
                return true;
        }

        return false;
}

static bool smb347_readable_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case CFG_CHARGE_CURRENT:
        case CFG_CURRENT_LIMIT:
        case CFG_FLOAT_VOLTAGE:
        case CFG_STAT:
        case CFG_PIN:
        case CFG_THERM:
        case CFG_SYSOK:
        case CFG_OTHER:
        case CFG_OTG:
        case CFG_TEMP_LIMIT:
        case CFG_FAULT_IRQ:
        case CFG_STATUS_IRQ:
        case CFG_ADDRESS:
        case CMD_A:
        case CMD_B:
        case CMD_C:
                return true;
        }

        return smb347_volatile_reg(dev, reg);
}

static void smb347_dt_parse_dev_info(struct smb347_charger *smb)
{
        struct device *dev = smb->dev;

        smb->soft_temp_limit_compensation =
                                        SMB3XX_SOFT_TEMP_COMPENSATE_DEFAULT;
        /*
         * These properties come from the battery info, still we need to
         * pre-initialize the values. See smb347_get_battery_info() below.
         */
        smb->soft_cold_temp_limit = SMB3XX_TEMP_USE_DEFAULT;
        smb->hard_cold_temp_limit = SMB3XX_TEMP_USE_DEFAULT;
        smb->soft_hot_temp_limit  = SMB3XX_TEMP_USE_DEFAULT;
        smb->hard_hot_temp_limit  = SMB3XX_TEMP_USE_DEFAULT;

        /* Charging constraints */
        device_property_read_u32(dev, "summit,fast-voltage-threshold-microvolt",
                                 &smb->pre_to_fast_voltage);
        device_property_read_u32(dev, "summit,mains-current-limit-microamp",
                                 &smb->mains_current_limit);
        device_property_read_u32(dev, "summit,usb-current-limit-microamp",
                                 &smb->usb_hc_current_limit);

        /* For thermometer monitoring */
        device_property_read_u32(dev, "summit,chip-temperature-threshold-celsius",
                                 &smb->chip_temp_threshold);
        device_property_read_u32(dev, "summit,soft-compensation-method",
                                 &smb->soft_temp_limit_compensation);
        device_property_read_u32(dev, "summit,charge-current-compensation-microamp",
                                 &smb->charge_current_compensation);

        /* Supported charging mode */
        smb->use_mains = device_property_read_bool(dev, "summit,enable-mains-charging");
        smb->use_usb = device_property_read_bool(dev, "summit,enable-usb-charging");
        smb->use_usb_otg = device_property_read_bool(dev, "summit,enable-otg-charging");

        /* Select charging control */
        device_property_read_u32(dev, "summit,enable-charge-control",
                                 &smb->enable_control);

        /*
         * Polarity of INOK signal indicating presence of external power
         * supply connected to the charger.
         */
        device_property_read_u32(dev, "summit,inok-polarity",
                                 &smb->inok_polarity);
}

static int smb347_get_battery_info(struct smb347_charger *smb)
{
        struct power_supply_battery_info info = {};
        struct power_supply *supply;
        int err;

        if (smb->mains)
                supply = smb->mains;
        else
                supply = smb->usb;

        err = power_supply_get_battery_info(supply, &info);
        if (err == -ENXIO || err == -ENODEV)
                return 0;
        if (err)
                return err;

        if (info.constant_charge_current_max_ua != -EINVAL)
                smb->max_charge_current = info.constant_charge_current_max_ua;

        if (info.constant_charge_voltage_max_uv != -EINVAL)
                smb->max_charge_voltage = info.constant_charge_voltage_max_uv;

        if (info.precharge_current_ua != -EINVAL)
                smb->pre_charge_current = info.precharge_current_ua;

        if (info.charge_term_current_ua != -EINVAL)
                smb->termination_current = info.charge_term_current_ua;

        if (info.temp_alert_min != INT_MIN)
                smb->soft_cold_temp_limit = info.temp_alert_min;

        if (info.temp_alert_max != INT_MAX)
                smb->soft_hot_temp_limit = info.temp_alert_max;

        if (info.temp_min != INT_MIN)
                smb->hard_cold_temp_limit = info.temp_min;

        if (info.temp_max != INT_MAX)
                smb->hard_hot_temp_limit = info.temp_max;

        /* Suspend when battery temperature is outside hard limits */
        if (smb->hard_cold_temp_limit != SMB3XX_TEMP_USE_DEFAULT ||
            smb->hard_hot_temp_limit != SMB3XX_TEMP_USE_DEFAULT)
                smb->suspend_on_hard_temp_limit = true;

        return 0;
}

static int smb347_usb_vbus_get_current_limit(struct regulator_dev *rdev)
{
        struct smb347_charger *smb = rdev_get_drvdata(rdev);
        unsigned int val;
        int ret;

        ret = regmap_read(smb->regmap, CFG_OTG, &val);
        if (ret < 0)
                return ret;

        /*
         * It's unknown what happens if this bit is unset due to lack of
         * access to the datasheet, assume it's limit-enable.
         */
        if (!(val & CFG_OTG_CURRENT_LIMIT_250mA))
                return 0;

        return val & CFG_OTG_CURRENT_LIMIT_750mA ? 750000 : 250000;
}

static int smb347_usb_vbus_set_new_current_limit(struct smb347_charger *smb,
                                                 int max_uA)
{
        const unsigned int mask = CFG_OTG_CURRENT_LIMIT_750mA |
                                  CFG_OTG_CURRENT_LIMIT_250mA;
        unsigned int val = CFG_OTG_CURRENT_LIMIT_250mA;
        int ret;

        if (max_uA >= 750000)
                val |= CFG_OTG_CURRENT_LIMIT_750mA;

        ret = regmap_update_bits(smb->regmap, CFG_OTG, mask, val);
        if (ret < 0)
                dev_err(smb->dev, "failed to change USB current limit\n");

        return ret;
}

static int smb347_usb_vbus_set_current_limit(struct regulator_dev *rdev,
                                             int min_uA, int max_uA)
{
        struct smb347_charger *smb = rdev_get_drvdata(rdev);
        int ret;

        ret = smb347_set_writable(smb, true, true);
        if (ret < 0)
                return ret;

        ret = smb347_usb_vbus_set_new_current_limit(smb, max_uA);
        smb347_set_writable(smb, false, true);

        return ret;
}

static int smb347_usb_vbus_regulator_enable(struct regulator_dev *rdev)
{
        struct smb347_charger *smb = rdev_get_drvdata(rdev);
        int ret, max_uA;

        ret = smb347_set_writable(smb, true, true);
        if (ret < 0)
                return ret;

        smb347_charging_disable(smb);

        if (device_property_read_bool(&rdev->dev, "summit,needs-inok-toggle")) {
                unsigned int sysok = 0;

                if (smb->inok_polarity == SMB3XX_SYSOK_INOK_ACTIVE_LOW)
                        sysok = CFG_SYSOK_INOK_ACTIVE_HIGH;

                /*
                 * VBUS won't be powered if INOK is active, so we need to
                 * manually disable INOK on some platforms.
                 */
                ret = regmap_update_bits(smb->regmap, CFG_SYSOK,
                                         CFG_SYSOK_INOK_ACTIVE_HIGH, sysok);
                if (ret < 0) {
                        dev_err(smb->dev, "failed to disable INOK\n");
                        goto done;
                }
        }

        ret = smb347_usb_vbus_get_current_limit(rdev);
        if (ret < 0) {
                dev_err(smb->dev, "failed to get USB VBUS current limit\n");
                goto done;
        }

        max_uA = ret;

        ret = smb347_usb_vbus_set_new_current_limit(smb, 250000);
        if (ret < 0) {
                dev_err(smb->dev, "failed to preset USB VBUS current limit\n");
                goto done;
        }

        ret = regmap_set_bits(smb->regmap, CMD_A, CMD_A_OTG_ENABLED);
        if (ret < 0) {
                dev_err(smb->dev, "failed to enable USB VBUS\n");
                goto done;
        }

        smb->usb_vbus_enabled = true;

        ret = smb347_usb_vbus_set_new_current_limit(smb, max_uA);
        if (ret < 0) {
                dev_err(smb->dev, "failed to restore USB VBUS current limit\n");
                goto done;
        }
done:
        smb347_set_writable(smb, false, true);

        return ret;
}

static int smb347_usb_vbus_regulator_disable(struct regulator_dev *rdev)
{
        struct smb347_charger *smb = rdev_get_drvdata(rdev);
        int ret;

        ret = smb347_set_writable(smb, true, true);
        if (ret < 0)
                return ret;

        ret = regmap_clear_bits(smb->regmap, CMD_A, CMD_A_OTG_ENABLED);
        if (ret < 0) {
                dev_err(smb->dev, "failed to disable USB VBUS\n");
                goto done;
        }

        smb->usb_vbus_enabled = false;

        if (device_property_read_bool(&rdev->dev, "summit,needs-inok-toggle")) {
                unsigned int sysok = 0;

                if (smb->inok_polarity == SMB3XX_SYSOK_INOK_ACTIVE_HIGH)
                        sysok = CFG_SYSOK_INOK_ACTIVE_HIGH;

                ret = regmap_update_bits(smb->regmap, CFG_SYSOK,
                                         CFG_SYSOK_INOK_ACTIVE_HIGH, sysok);
                if (ret < 0) {
                        dev_err(smb->dev, "failed to enable INOK\n");
                        goto done;
                }
        }

        smb347_start_stop_charging(smb);
done:
        smb347_set_writable(smb, false, true);

        return ret;
}

static const struct regmap_config smb347_regmap = {
        .reg_bits       = 8,
        .val_bits       = 8,
        .max_register   = SMB347_MAX_REGISTER,
        .volatile_reg   = smb347_volatile_reg,
        .readable_reg   = smb347_readable_reg,
        .cache_type     = REGCACHE_FLAT,
        .num_reg_defaults_raw = SMB347_MAX_REGISTER,
};

static const struct regulator_ops smb347_usb_vbus_regulator_ops = {
        .is_enabled     = regulator_is_enabled_regmap,
        .enable         = smb347_usb_vbus_regulator_enable,
        .disable        = smb347_usb_vbus_regulator_disable,
        .get_current_limit = smb347_usb_vbus_get_current_limit,
        .set_current_limit = smb347_usb_vbus_set_current_limit,
};

static const struct power_supply_desc smb347_mains_desc = {
        .name           = "smb347-mains",
        .type           = POWER_SUPPLY_TYPE_MAINS,
        .get_property   = smb347_get_property,
        .properties     = smb347_properties,
        .num_properties = ARRAY_SIZE(smb347_properties),
};

static const struct power_supply_desc smb347_usb_desc = {
        .name           = "smb347-usb",
        .type           = POWER_SUPPLY_TYPE_USB,
        .get_property   = smb347_get_property,
        .properties     = smb347_properties,
        .num_properties = ARRAY_SIZE(smb347_properties),
};

static const struct regulator_desc smb347_usb_vbus_regulator_desc = {
        .name           = "smb347-usb-vbus",
        .of_match       = of_match_ptr("usb-vbus"),
        .ops            = &smb347_usb_vbus_regulator_ops,
        .type           = REGULATOR_VOLTAGE,
        .owner          = THIS_MODULE,
        .enable_reg     = CMD_A,
        .enable_mask    = CMD_A_OTG_ENABLED,
        .enable_val     = CMD_A_OTG_ENABLED,
        .fixed_uV       = 5000000,
        .n_voltages     = 1,
};

static int smb347_probe(struct i2c_client *client,
                        const struct i2c_device_id *id)
{
        struct power_supply_config mains_usb_cfg = {};
        struct regulator_config usb_rdev_cfg = {};
        struct device *dev = &client->dev;
        struct smb347_charger *smb;
        int ret;

        smb = devm_kzalloc(dev, sizeof(*smb), GFP_KERNEL);
        if (!smb)
                return -ENOMEM;
        smb->dev = &client->dev;
        smb->id = id->driver_data;
        i2c_set_clientdata(client, smb);

        smb347_dt_parse_dev_info(smb);
        if (!smb->use_mains && !smb->use_usb)
                return -EINVAL;

        smb->regmap = devm_regmap_init_i2c(client, &smb347_regmap);
        if (IS_ERR(smb->regmap))
                return PTR_ERR(smb->regmap);

        mains_usb_cfg.drv_data = smb;
        mains_usb_cfg.of_node = dev->of_node;
        if (smb->use_mains) {
                smb->mains = devm_power_supply_register(dev, &smb347_mains_desc,
                                                        &mains_usb_cfg);
                if (IS_ERR(smb->mains))
                        return PTR_ERR(smb->mains);
        }

        if (smb->use_usb) {
                smb->usb = devm_power_supply_register(dev, &smb347_usb_desc,
                                                      &mains_usb_cfg);
                if (IS_ERR(smb->usb))
                        return PTR_ERR(smb->usb);
        }

        ret = smb347_get_battery_info(smb);
        if (ret)
                return ret;

        ret = smb347_hw_init(smb);
        if (ret < 0)
                return ret;

        ret = smb347_irq_init(smb, client);
        if (ret)
                return ret;

        usb_rdev_cfg.dev = dev;
        usb_rdev_cfg.driver_data = smb;
        usb_rdev_cfg.regmap = smb->regmap;

        smb->usb_rdev = devm_regulator_register(dev,
                                                &smb347_usb_vbus_regulator_desc,
                                                &usb_rdev_cfg);
        if (IS_ERR(smb->usb_rdev)) {
                smb347_irq_disable(smb);
                return PTR_ERR(smb->usb_rdev);
        }

        return 0;
}

static int smb347_remove(struct i2c_client *client)
{
        struct smb347_charger *smb = i2c_get_clientdata(client);

        smb347_usb_vbus_regulator_disable(smb->usb_rdev);
        smb347_irq_disable(smb);

        return 0;
}

static void smb347_shutdown(struct i2c_client *client)
{
        smb347_remove(client);
}

static const struct i2c_device_id smb347_id[] = {
        { "smb345", SMB345 },
        { "smb347", SMB347 },
        { "smb358", SMB358 },
        { },
};
MODULE_DEVICE_TABLE(i2c, smb347_id);

static const struct of_device_id smb3xx_of_match[] = {
        { .compatible = "summit,smb345" },
        { .compatible = "summit,smb347" },
        { .compatible = "summit,smb358" },
        { },
};
MODULE_DEVICE_TABLE(of, smb3xx_of_match);

static struct i2c_driver smb347_driver = {
        .driver = {
                .name = "smb347",
                .of_match_table = smb3xx_of_match,
        },
        .probe = smb347_probe,
        .remove = smb347_remove,
        .shutdown = smb347_shutdown,
        .id_table = smb347_id,
};
module_i2c_driver(smb347_driver);

MODULE_AUTHOR("Bruce E. Robertson <bruce.e.robertson@intel.com>");
MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
MODULE_DESCRIPTION("SMB347 battery charger driver");
MODULE_LICENSE("GPL");