root/drivers/power/supply/wm8350_power.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Battery driver for wm8350 PMIC
 *
 * Copyright 2007, 2008 Wolfson Microelectronics PLC.
 *
 * Based on OLPC Battery Driver
 *
 * Copyright 2006  David Woodhouse <dwmw2@infradead.org>
 */

#include <linux/module.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/mfd/wm8350/supply.h>
#include <linux/mfd/wm8350/core.h>
#include <linux/mfd/wm8350/comparator.h>

static int wm8350_read_battery_uvolts(struct wm8350 *wm8350)
{
        return wm8350_read_auxadc(wm8350, WM8350_AUXADC_BATT, 0, 0)
                * WM8350_AUX_COEFF;
}

static int wm8350_read_line_uvolts(struct wm8350 *wm8350)
{
        return wm8350_read_auxadc(wm8350, WM8350_AUXADC_LINE, 0, 0)
                * WM8350_AUX_COEFF;
}

static int wm8350_read_usb_uvolts(struct wm8350 *wm8350)
{
        return wm8350_read_auxadc(wm8350, WM8350_AUXADC_USB, 0, 0)
                * WM8350_AUX_COEFF;
}

#define WM8350_BATT_SUPPLY      1
#define WM8350_USB_SUPPLY       2
#define WM8350_LINE_SUPPLY      4

static inline int wm8350_charge_time_min(struct wm8350 *wm8350, int min)
{
        if (!wm8350->power.rev_g_coeff)
                return (((min - 30) / 15) & 0xf) << 8;
        else
                return (((min - 30) / 30) & 0xf) << 8;
}

static int wm8350_get_supplies(struct wm8350 *wm8350)
{
        u16 sm, ov, co, chrg;
        int supplies = 0;

        sm = wm8350_reg_read(wm8350, WM8350_STATE_MACHINE_STATUS);
        ov = wm8350_reg_read(wm8350, WM8350_MISC_OVERRIDES);
        co = wm8350_reg_read(wm8350, WM8350_COMPARATOR_OVERRIDES);
        chrg = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2);

        /* USB_SM */
        sm = (sm & WM8350_USB_SM_MASK) >> WM8350_USB_SM_SHIFT;

        /* CHG_ISEL */
        chrg &= WM8350_CHG_ISEL_MASK;

        /* If the USB state machine is active then we're using that with or
         * without battery, otherwise check for wall supply */
        if (((sm == WM8350_USB_SM_100_SLV) ||
             (sm == WM8350_USB_SM_500_SLV) ||
             (sm == WM8350_USB_SM_STDBY_SLV))
            && !(ov & WM8350_USB_LIMIT_OVRDE))
                supplies = WM8350_USB_SUPPLY;
        else if (((sm == WM8350_USB_SM_100_SLV) ||
                  (sm == WM8350_USB_SM_500_SLV) ||
                  (sm == WM8350_USB_SM_STDBY_SLV))
                 && (ov & WM8350_USB_LIMIT_OVRDE) && (chrg == 0))
                supplies = WM8350_USB_SUPPLY | WM8350_BATT_SUPPLY;
        else if (co & WM8350_WALL_FB_OVRDE)
                supplies = WM8350_LINE_SUPPLY;
        else
                supplies = WM8350_BATT_SUPPLY;

        return supplies;
}

static int wm8350_charger_config(struct wm8350 *wm8350,
                                 struct wm8350_charger_policy *policy)
{
        u16 reg, eoc_mA, fast_limit_mA;

        if (!policy) {
                dev_warn(wm8350->dev,
                         "No charger policy, charger not configured.\n");
                return -EINVAL;
        }

        /* make sure USB fast charge current is not > 500mA */
        if (policy->fast_limit_USB_mA > 500) {
                dev_err(wm8350->dev, "USB fast charge > 500mA\n");
                return -EINVAL;
        }

        eoc_mA = WM8350_CHG_EOC_mA(policy->eoc_mA);

        wm8350_reg_unlock(wm8350);

        reg = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_1)
                & WM8350_CHG_ENA_R168;
        wm8350_reg_write(wm8350, WM8350_BATTERY_CHARGER_CONTROL_1,
                         reg | eoc_mA | policy->trickle_start_mV |
                         WM8350_CHG_TRICKLE_TEMP_CHOKE |
                         WM8350_CHG_TRICKLE_USB_CHOKE |
                         WM8350_CHG_FAST_USB_THROTTLE);

        if (wm8350_get_supplies(wm8350) & WM8350_USB_SUPPLY) {
                fast_limit_mA =
                        WM8350_CHG_FAST_LIMIT_mA(policy->fast_limit_USB_mA);
                wm8350_reg_write(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2,
                            policy->charge_mV | policy->trickle_charge_USB_mA |
                            fast_limit_mA | wm8350_charge_time_min(wm8350,
                                                policy->charge_timeout));

        } else {
                fast_limit_mA =
                        WM8350_CHG_FAST_LIMIT_mA(policy->fast_limit_mA);
                wm8350_reg_write(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2,
                            policy->charge_mV | policy->trickle_charge_mA |
                            fast_limit_mA | wm8350_charge_time_min(wm8350,
                                                policy->charge_timeout));
        }

        wm8350_reg_lock(wm8350);
        return 0;
}

static int wm8350_batt_status(struct wm8350 *wm8350)
{
        u16 state;

        state = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2);
        state &= WM8350_CHG_STS_MASK;

        switch (state) {
        case WM8350_CHG_STS_OFF:
                return POWER_SUPPLY_STATUS_DISCHARGING;

        case WM8350_CHG_STS_TRICKLE:
        case WM8350_CHG_STS_FAST:
                return POWER_SUPPLY_STATUS_CHARGING;

        default:
                return POWER_SUPPLY_STATUS_UNKNOWN;
        }
}

static ssize_t charger_state_show(struct device *dev,
                                 struct device_attribute *attr, char *buf)
{
        struct wm8350 *wm8350 = dev_get_drvdata(dev);
        char *charge;
        int state;

        state = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2) &
            WM8350_CHG_STS_MASK;
        switch (state) {
        case WM8350_CHG_STS_OFF:
                charge = "Charger Off";
                break;
        case WM8350_CHG_STS_TRICKLE:
                charge = "Trickle Charging";
                break;
        case WM8350_CHG_STS_FAST:
                charge = "Fast Charging";
                break;
        default:
                return 0;
        }

        return sysfs_emit(buf, "%s\n", charge);
}

static DEVICE_ATTR_RO(charger_state);

static irqreturn_t wm8350_charger_handler(int irq, void *data)
{
        struct wm8350 *wm8350 = data;
        struct wm8350_power *power = &wm8350->power;
        struct wm8350_charger_policy *policy = power->policy;

        switch (irq - wm8350->irq_base) {
        case WM8350_IRQ_CHG_BAT_FAIL:
                dev_err(wm8350->dev, "battery failed\n");
                break;
        case WM8350_IRQ_CHG_TO:
                dev_err(wm8350->dev, "charger timeout\n");
                power_supply_changed(power->battery);
                break;

        case WM8350_IRQ_CHG_BAT_HOT:
        case WM8350_IRQ_CHG_BAT_COLD:
        case WM8350_IRQ_CHG_START:
        case WM8350_IRQ_CHG_END:
                power_supply_changed(power->battery);
                break;

        case WM8350_IRQ_CHG_FAST_RDY:
                dev_dbg(wm8350->dev, "fast charger ready\n");
                wm8350_charger_config(wm8350, policy);
                wm8350_reg_unlock(wm8350);
                wm8350_set_bits(wm8350, WM8350_BATTERY_CHARGER_CONTROL_1,
                                WM8350_CHG_FAST);
                wm8350_reg_lock(wm8350);
                break;

        case WM8350_IRQ_CHG_VBATT_LT_3P9:
                dev_warn(wm8350->dev, "battery < 3.9V\n");
                break;
        case WM8350_IRQ_CHG_VBATT_LT_3P1:
                dev_warn(wm8350->dev, "battery < 3.1V\n");
                break;
        case WM8350_IRQ_CHG_VBATT_LT_2P85:
                dev_warn(wm8350->dev, "battery < 2.85V\n");
                break;

                /* Supply change.  We will overnotify but it should do
                 * no harm. */
        case WM8350_IRQ_EXT_USB_FB:
        case WM8350_IRQ_EXT_WALL_FB:
                wm8350_charger_config(wm8350, policy);
                fallthrough;
        case WM8350_IRQ_EXT_BAT_FB:
                power_supply_changed(power->battery);
                power_supply_changed(power->usb);
                power_supply_changed(power->ac);
                break;

        default:
                dev_err(wm8350->dev, "Unknown interrupt %d\n", irq);
        }

        return IRQ_HANDLED;
}

/*********************************************************************
 *              AC Power
 *********************************************************************/
static int wm8350_ac_get_prop(struct power_supply *psy,
                              enum power_supply_property psp,
                              union power_supply_propval *val)
{
        struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
        int ret = 0;

        switch (psp) {
        case POWER_SUPPLY_PROP_ONLINE:
                val->intval = !!(wm8350_get_supplies(wm8350) &
                                 WM8350_LINE_SUPPLY);
                break;
        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
                val->intval = wm8350_read_line_uvolts(wm8350);
                break;
        default:
                ret = -EINVAL;
                break;
        }
        return ret;
}

static enum power_supply_property wm8350_ac_props[] = {
        POWER_SUPPLY_PROP_ONLINE,
        POWER_SUPPLY_PROP_VOLTAGE_NOW,
};

/*********************************************************************
 *              USB Power
 *********************************************************************/
static int wm8350_usb_get_prop(struct power_supply *psy,
                               enum power_supply_property psp,
                               union power_supply_propval *val)
{
        struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
        int ret = 0;

        switch (psp) {
        case POWER_SUPPLY_PROP_ONLINE:
                val->intval = !!(wm8350_get_supplies(wm8350) &
                                 WM8350_USB_SUPPLY);
                break;
        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
                val->intval = wm8350_read_usb_uvolts(wm8350);
                break;
        default:
                ret = -EINVAL;
                break;
        }
        return ret;
}

static enum power_supply_property wm8350_usb_props[] = {
        POWER_SUPPLY_PROP_ONLINE,
        POWER_SUPPLY_PROP_VOLTAGE_NOW,
};

/*********************************************************************
 *              Battery properties
 *********************************************************************/

static int wm8350_bat_check_health(struct wm8350 *wm8350)
{
        u16 reg;

        if (wm8350_read_battery_uvolts(wm8350) < 2850000)
                return POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;

        reg = wm8350_reg_read(wm8350, WM8350_CHARGER_OVERRIDES);
        if (reg & WM8350_CHG_BATT_HOT_OVRDE)
                return POWER_SUPPLY_HEALTH_OVERHEAT;

        if (reg & WM8350_CHG_BATT_COLD_OVRDE)
                return POWER_SUPPLY_HEALTH_COLD;

        return POWER_SUPPLY_HEALTH_GOOD;
}

static int wm8350_bat_get_charge_type(struct wm8350 *wm8350)
{
        int state;

        state = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2) &
            WM8350_CHG_STS_MASK;
        switch (state) {
        case WM8350_CHG_STS_OFF:
                return POWER_SUPPLY_CHARGE_TYPE_NONE;
        case WM8350_CHG_STS_TRICKLE:
                return POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
        case WM8350_CHG_STS_FAST:
                return POWER_SUPPLY_CHARGE_TYPE_FAST;
        default:
                return POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
        }
}

static int wm8350_bat_get_property(struct power_supply *psy,
                                   enum power_supply_property psp,
                                   union power_supply_propval *val)
{
        struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
        int ret = 0;

        switch (psp) {
        case POWER_SUPPLY_PROP_STATUS:
                val->intval = wm8350_batt_status(wm8350);
                break;
        case POWER_SUPPLY_PROP_ONLINE:
                val->intval = !!(wm8350_get_supplies(wm8350) &
                                 WM8350_BATT_SUPPLY);
                break;
        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
                val->intval = wm8350_read_battery_uvolts(wm8350);
                break;
        case POWER_SUPPLY_PROP_HEALTH:
                val->intval = wm8350_bat_check_health(wm8350);
                break;
        case POWER_SUPPLY_PROP_CHARGE_TYPE:
                val->intval = wm8350_bat_get_charge_type(wm8350);
                break;
        default:
                ret = -EINVAL;
                break;
        }

        return ret;
}

static enum power_supply_property wm8350_bat_props[] = {
        POWER_SUPPLY_PROP_STATUS,
        POWER_SUPPLY_PROP_ONLINE,
        POWER_SUPPLY_PROP_VOLTAGE_NOW,
        POWER_SUPPLY_PROP_HEALTH,
        POWER_SUPPLY_PROP_CHARGE_TYPE,
};

static const struct power_supply_desc wm8350_ac_desc = {
        .name           = "wm8350-ac",
        .type           = POWER_SUPPLY_TYPE_MAINS,
        .properties     = wm8350_ac_props,
        .num_properties = ARRAY_SIZE(wm8350_ac_props),
        .get_property   = wm8350_ac_get_prop,
};

static const struct power_supply_desc wm8350_battery_desc = {
        .name           = "wm8350-battery",
        .properties     = wm8350_bat_props,
        .num_properties = ARRAY_SIZE(wm8350_bat_props),
        .get_property   = wm8350_bat_get_property,
        .use_for_apm    = 1,
};

static const struct power_supply_desc wm8350_usb_desc = {
        .name           = "wm8350-usb",
        .type           = POWER_SUPPLY_TYPE_USB,
        .properties     = wm8350_usb_props,
        .num_properties = ARRAY_SIZE(wm8350_usb_props),
        .get_property   = wm8350_usb_get_prop,
};

/*********************************************************************
 *              Initialisation
 *********************************************************************/

static int wm8350_init_charger(struct wm8350 *wm8350)
{
        int ret;

        /* register our interest in charger events */
        ret = wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_HOT,
                            wm8350_charger_handler, 0, "Battery hot", wm8350);
        if (ret)
                goto err;

        ret = wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_COLD,
                            wm8350_charger_handler, 0, "Battery cold", wm8350);
        if (ret)
                goto free_chg_bat_hot;

        ret = wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_FAIL,
                            wm8350_charger_handler, 0, "Battery fail", wm8350);
        if (ret)
                goto free_chg_bat_cold;

        ret = wm8350_register_irq(wm8350, WM8350_IRQ_CHG_TO,
                            wm8350_charger_handler, 0,
                            "Charger timeout", wm8350);
        if (ret)
                goto free_chg_bat_fail;

        ret = wm8350_register_irq(wm8350, WM8350_IRQ_CHG_END,
                            wm8350_charger_handler, 0,
                            "Charge end", wm8350);
        if (ret)
                goto free_chg_to;

        ret = wm8350_register_irq(wm8350, WM8350_IRQ_CHG_START,
                            wm8350_charger_handler, 0,
                            "Charge start", wm8350);
        if (ret)
                goto free_chg_end;

        ret = wm8350_register_irq(wm8350, WM8350_IRQ_CHG_FAST_RDY,
                            wm8350_charger_handler, 0,
                            "Fast charge ready", wm8350);
        if (ret)
                goto free_chg_start;

        ret = wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P9,
                            wm8350_charger_handler, 0,
                            "Battery <3.9V", wm8350);
        if (ret)
                goto free_chg_fast_rdy;

        ret = wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P1,
                            wm8350_charger_handler, 0,
                            "Battery <3.1V", wm8350);
        if (ret)
                goto free_chg_vbatt_lt_3p9;

        ret = wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_2P85,
                            wm8350_charger_handler, 0,
                            "Battery <2.85V", wm8350);
        if (ret)
                goto free_chg_vbatt_lt_3p1;

        /* and supply change events */
        ret = wm8350_register_irq(wm8350, WM8350_IRQ_EXT_USB_FB,
                            wm8350_charger_handler, 0, "USB", wm8350);
        if (ret)
                goto free_chg_vbatt_lt_2p85;

        ret = wm8350_register_irq(wm8350, WM8350_IRQ_EXT_WALL_FB,
                            wm8350_charger_handler, 0, "Wall", wm8350);
        if (ret)
                goto free_ext_usb_fb;

        ret = wm8350_register_irq(wm8350, WM8350_IRQ_EXT_BAT_FB,
                            wm8350_charger_handler, 0, "Battery", wm8350);
        if (ret)
                goto free_ext_wall_fb;

        return 0;

free_ext_wall_fb:
        wm8350_free_irq(wm8350, WM8350_IRQ_EXT_WALL_FB, wm8350);
free_ext_usb_fb:
        wm8350_free_irq(wm8350, WM8350_IRQ_EXT_USB_FB, wm8350);
free_chg_vbatt_lt_2p85:
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_2P85, wm8350);
free_chg_vbatt_lt_3p1:
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P1, wm8350);
free_chg_vbatt_lt_3p9:
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P9, wm8350);
free_chg_fast_rdy:
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_FAST_RDY, wm8350);
free_chg_start:
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_START, wm8350);
free_chg_end:
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_END, wm8350);
free_chg_to:
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_TO, wm8350);
free_chg_bat_fail:
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_FAIL, wm8350);
free_chg_bat_cold:
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_COLD, wm8350);
free_chg_bat_hot:
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_HOT, wm8350);
err:
        return ret;
}

static void free_charger_irq(struct wm8350 *wm8350)
{
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_HOT, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_COLD, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_FAIL, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_TO, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_END, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_START, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_FAST_RDY, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P9, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P1, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_2P85, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_EXT_USB_FB, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_EXT_WALL_FB, wm8350);
        wm8350_free_irq(wm8350, WM8350_IRQ_EXT_BAT_FB, wm8350);
}

static int wm8350_power_probe(struct platform_device *pdev)
{
        struct wm8350 *wm8350 = platform_get_drvdata(pdev);
        struct wm8350_power *power = &wm8350->power;
        struct wm8350_charger_policy *policy = power->policy;
        int ret;

        power->ac = devm_power_supply_register(&pdev->dev, &wm8350_ac_desc, NULL);
        if (IS_ERR(power->ac))
                return PTR_ERR(power->ac);

        power->battery = devm_power_supply_register(&pdev->dev, &wm8350_battery_desc, NULL);
        if (IS_ERR(power->battery))
                return PTR_ERR(power->battery);

        power->usb = devm_power_supply_register(&pdev->dev, &wm8350_usb_desc, NULL);
        if (IS_ERR(power->usb))
                return PTR_ERR(power->usb);

        ret = device_create_file(&pdev->dev, &dev_attr_charger_state);
        if (ret < 0)
                dev_warn(wm8350->dev, "failed to add charge sysfs: %d\n", ret);
        ret = 0;

        wm8350_init_charger(wm8350);
        if (wm8350_charger_config(wm8350, policy) == 0) {
                wm8350_reg_unlock(wm8350);
                wm8350_set_bits(wm8350, WM8350_POWER_MGMT_5, WM8350_CHG_ENA);
                wm8350_reg_lock(wm8350);
        }

        return ret;
}

static void wm8350_power_remove(struct platform_device *pdev)
{
        struct wm8350 *wm8350 = platform_get_drvdata(pdev);

        free_charger_irq(wm8350);
        device_remove_file(&pdev->dev, &dev_attr_charger_state);
}

static struct platform_driver wm8350_power_driver = {
        .probe = wm8350_power_probe,
        .remove = wm8350_power_remove,
        .driver = {
                .name = "wm8350-power",
        },
};

module_platform_driver(wm8350_power_driver);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Power supply driver for WM8350");
MODULE_ALIAS("platform:wm8350-power");