/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2016 Jared McNeill <jmcneill@invisible.ca>
 * Copyright (c) 2018 Emmanuel Vadot <manu@FreeBSD.org>
 * Copyright (c) 2019 Michal Meloun <mmel@FreeBSD.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/rman.h>
#include <machine/bus.h>

#include <dev/iicbus/iiconf.h>
#include <dev/iicbus/iicbus.h>

#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>

#include <dev/regulator/regulator.h>

#include "regdev_if.h"

/* Registers */
#define FAN53555_VSEL0          0x00
#define FAN53555_VSEL1          0x01
#define  FAN53555_VSEL_ENA              (1 << 7)
#define  FAN53555_VSEL_MODE             (1 << 6)
#define  FAN53555_VSEL_MASK             0x3f
#define FAN53555_CTRL           0x02
#define FAN53555_ID1            0x03
#define  FAN53555_ID1_DIE_ID(x)         ((x) & 0x0F)
#define FAN53555_ID2            0x04
#define  FAN53555_ID2_DIE_REV(x)        ((x) & 0x0F)
#define FAN53555_MON            0x05

#define TCS4525_VSEL0           0x11
#define TCS4525_VSEL1           0x10
#define TCS4525_CHIP_ID_12      12

#if 0
#define dprintf(sc, format, arg...)                                     \
        device_printf(sc->base_dev, "%s: " format, __func__, arg)
#else
#define dprintf(sc, format, arg...)
#endif

enum fan53555_pmic_type {
        FAN53555 = 1,
        SYR827,
        SYR828,
        TCS4525,
};

static struct ofw_compat_data compat_data[] = {
        {"fcs,fan53555",        FAN53555},
        {"silergy,syr827",      SYR827},
        {"silergy,syr828",      SYR828},
        {"tcs,tcs4525",         TCS4525},
        {NULL,          0}
};

struct fan53555_reg_sc {
        struct regnode          *regnode;
        char                    *name;
        device_t                base_dev;
        uint8_t                 live_reg;
        uint8_t                 sleep_reg;
        struct regulator_range  *range;
        struct regnode_std_param *param;
};

struct fan53555_softc {
        device_t                dev;
        uint8_t                 live_reg;
        uint8_t                 sleep_reg;
};

static struct regulator_range syr_8_range =
   REG_RANGE_INIT(  0, 0x3F,  712500, 12500);

static struct regulator_range fan_0_0_range =
   REG_RANGE_INIT(  0, 0x3F,  600000, 10000);
static struct regulator_range fan_0_13_range =
   REG_RANGE_INIT(  0, 0x3F,  800000, 10000);
static struct regulator_range fan_1_range =
   REG_RANGE_INIT(  0, 0x3F,  600000, 10000);
static struct regulator_range fan_4_range =
   REG_RANGE_INIT(  0, 0x3F,  603000, 12826);

static struct regulator_range tcs_12_range =
   REG_RANGE_INIT(  0, 0x3F,  800000, 6250);

static int
fan53555_read(device_t dev, uint8_t reg, uint8_t *val)
{
        uint8_t addr;
        int rv;
        struct iic_msg msgs[2] = {
                {0, IIC_M_WR | IIC_M_NOSTOP, 1, &addr},
                {0, IIC_M_RD, 1, val},
        };

        msgs[0].slave = iicbus_get_addr(dev);
        msgs[1].slave = iicbus_get_addr(dev);
        addr = reg;

        rv = iicbus_transfer_excl(dev, msgs, 2, IIC_INTRWAIT);
        if (rv != 0) {
                device_printf(dev, "Error when reading reg 0x%02X, rv: %d\n",
                    reg,  rv);
                return (EIO);
        }

        return (0);
}

static int
fan53555_write(device_t dev, uint8_t reg, uint8_t val)
{
        uint8_t data[2];
        int rv;

        struct iic_msg msgs[1] = {
                {0, IIC_M_WR, 2, data},
        };

        msgs[0].slave = iicbus_get_addr(dev);
        data[0] = reg;
        data[1] = val;

        rv = iicbus_transfer_excl(dev, msgs, 1, IIC_INTRWAIT);
        if (rv != 0) {
                device_printf(dev,
                    "Error when writing reg 0x%02X, rv: %d\n", reg, rv);
                return (EIO);
        }
        return (0);
}

static int
fan53555_read_sel(struct fan53555_reg_sc *sc, uint8_t *sel)
{
        int rv;

        rv = fan53555_read(sc->base_dev, sc->live_reg, sel);
        if (rv != 0)
                return (rv);
        *sel &= FAN53555_VSEL_MASK;
        return (0);
}

static int
fan53555_write_sel(struct fan53555_reg_sc *sc, uint8_t sel)
{
        int rv;
        uint8_t reg;

        rv = fan53555_read(sc->base_dev, sc->live_reg, &reg);
        if (rv != 0)
                return (rv);
        reg &= ~FAN53555_VSEL_MASK;
        reg |= sel;

        rv = fan53555_write(sc->base_dev, sc->live_reg, reg);
        if (rv != 0)
                return (rv);
        return (rv);
}

static int
fan53555_regnode_init(struct regnode *regnode)
{
        return (0);
}

static int
fan53555_regnode_enable(struct regnode *regnode, bool enable, int *udelay)
{
        struct fan53555_reg_sc *sc;
        uint8_t val;

        sc = regnode_get_softc(regnode);

        dprintf(sc, "%sabling regulator %s\n", enable ? "En" : "Dis",
            sc->name);
        fan53555_read(sc->base_dev, sc->live_reg, &val);
        if (enable)
                val |=FAN53555_VSEL_ENA;
        else
                val &= ~FAN53555_VSEL_ENA;
        fan53555_write(sc->base_dev, sc->live_reg, val);

        *udelay = sc->param->enable_delay;
        return (0);
}


static int
fan53555_regnode_set_voltage(struct regnode *regnode, int min_uvolt,
    int max_uvolt, int *udelay)
{
        struct fan53555_reg_sc *sc;
        uint8_t sel;
        int uvolt, rv;

        sc = regnode_get_softc(regnode);

        dprintf(sc, "Setting %s to %d<->%d uvolts\n", sc->name, min_uvolt,
            max_uvolt);
        rv = regulator_range_volt_to_sel8(sc->range, 1, min_uvolt, max_uvolt,
            &sel);
        if (rv != 0)
                return (rv);
        *udelay = sc->param->ramp_delay;
        rv = fan53555_write_sel(sc, sel);
        dprintf(sc, "Regulator %s writing sel: 0x%02X\n", sc->name, sel);

        fan53555_read_sel(sc, &sel);
        regulator_range_sel8_to_volt(sc->range, 1, sel, &uvolt);
        dprintf(sc, "Regulator %s set to %d uvolt (sel: 0x%02X)\n", sc->name,
            uvolt, sel);

        return (rv);
}

static int
fan53555_regnode_get_voltage(struct regnode *regnode, int *uvolt)
{
        struct fan53555_reg_sc *sc;
        uint8_t sel;
        int rv;

        sc = regnode_get_softc(regnode);

        rv = fan53555_read_sel(sc, &sel);
        if (rv != 0)
                return (rv);
        rv = regulator_range_sel8_to_volt(sc->range, 1, sel, uvolt);
        dprintf(sc, "Regulator %s is at %d uvolt ((sel: 0x%02X)\n", sc->name,
            *uvolt, sel);

        return (rv);
}

static regnode_method_t fan53555_regnode_methods[] = {
        /* Regulator interface */
        REGNODEMETHOD(regnode_init,             fan53555_regnode_init),
        REGNODEMETHOD(regnode_enable,           fan53555_regnode_enable),
        REGNODEMETHOD(regnode_set_voltage,      fan53555_regnode_set_voltage),
        REGNODEMETHOD(regnode_get_voltage,      fan53555_regnode_get_voltage),
        REGNODEMETHOD_END
};
DEFINE_CLASS_1(fan53555_regnode, fan53555_regnode_class,
    fan53555_regnode_methods, sizeof(struct fan53555_reg_sc), regnode_class);

static struct regulator_range *
fan53555_get_range(struct fan53555_softc *sc, int type, uint8_t id,
    uint8_t rev)
{
        if (type == SYR827 || type == SYR828) {
                switch (id) {
                case 8:
                        return (&syr_8_range);
                default:
                        return (NULL);
                }
        }

        if (type == FAN53555) {
                switch (id) {
                case 0:
                        if (rev == 0)
                                return (&fan_0_0_range);
                        else if (rev == 13)
                                return (&fan_0_13_range);
                        else
                                return (NULL);
                case 1:
                case 3:
                case 5:
                case 8:
                        return (&fan_1_range);
                case 4:
                        return (&fan_4_range);
                default:
                        return (NULL);
                }
        }

        if (type == TCS4525) {
                switch (id) {
                case TCS4525_CHIP_ID_12:
                        return (&tcs_12_range);
                default:
                        return (NULL);
                }
        }

        return (NULL);
}

static struct fan53555_reg_sc *
fan53555_reg_attach(struct fan53555_softc *sc, phandle_t node, int  type)
{
        struct fan53555_reg_sc *reg_sc;
        struct regnode_init_def initdef;
        struct regnode *regnode;
        static struct regulator_range *range;
        uint8_t id1, id2;

        memset(&initdef, 0, sizeof(initdef));
        if (regulator_parse_ofw_stdparam(sc->dev, node, &initdef) != 0) {
                device_printf(sc->dev, "cannot parse regulator FDT data\n");
                return (NULL);
        }

        if (fan53555_read(sc->dev, FAN53555_ID1, &id1) != 0) {
                device_printf(sc->dev, "cannot read ID1\n");
                return (NULL);
        }

        if (fan53555_read(sc->dev, FAN53555_ID2, &id2) != 0) {
                device_printf(sc->dev, "cannot read ID2\n");
                return (NULL);
        }
        dprintf(sc, "Device ID1: 0x%02X, ID2: 0x%02X\n", id1, id2);

        range = fan53555_get_range(sc, type, FAN53555_ID1_DIE_ID(id1),
             FAN53555_ID2_DIE_REV(id2));
        if (range == NULL) {
                device_printf(sc->dev,
                    "cannot determine chip type (ID1: 0x%02X, ID2: 0x%02X)\n",
                    id1, id2);
                return (NULL);
        }

        initdef.id = 1;
        initdef.ofw_node = node;

        regnode = regnode_create(sc->dev, &fan53555_regnode_class, &initdef);
        if (regnode == NULL) {
                device_printf(sc->dev, "cannot create regulator\n");
                return (NULL);
        }

        reg_sc = regnode_get_softc(regnode);
        reg_sc->name = "fan53555";
        reg_sc->regnode = regnode;
        reg_sc->base_dev = sc->dev;
        reg_sc->param = regnode_get_stdparam(regnode);
        reg_sc->range = range;
        reg_sc->live_reg = sc->live_reg;
        reg_sc->sleep_reg = sc->sleep_reg;

        dprintf(sc->dev, "live_reg: %d, sleep_reg: %d\n", reg_sc->live_reg,
            reg_sc->sleep_reg);

        regnode_register(regnode);

        if (bootverbose) {
                int volt, rv;
                regnode_topo_slock();
                rv = regnode_get_voltage(regnode, &volt);
                if (rv == ENODEV) {
                        device_printf(sc->dev,
                           " Regulator %s: parent doesn't exist yet.\n",
                           regnode_get_name(regnode));
                } else if (rv != 0) {
                        device_printf(sc->dev,
                           " Regulator %s: voltage: INVALID!!!\n",
                           regnode_get_name(regnode));
                } else {
                        device_printf(sc->dev,
                            " Regulator %s: voltage: %d uV\n",
                            regnode_get_name(regnode), volt);
                }
                regnode_topo_unlock();
        }

        return (reg_sc);
}

static int
fan53555_probe(device_t dev)
{
        int type;

        if (!ofw_bus_status_okay(dev))
                return (ENXIO);

        type = ofw_bus_search_compatible(dev, compat_data)->ocd_data;
        switch (type) {
        case FAN53555:
                device_set_desc(dev, "FAN53555 PMIC");
                break;
        case SYR827:
                device_set_desc(dev, "SYR827 PMIC");
                break;
        case SYR828:
                device_set_desc(dev, "SYR828 PMIC");
                break;
        case TCS4525:
                device_set_desc(dev, "TCS4525 PMIC");
                break;
        default:
                return (ENXIO);
        }

        return (BUS_PROBE_DEFAULT);
}

static int
fan53555_attach(device_t dev)
{
        struct fan53555_softc *sc;
        phandle_t node;
        int type, susp_sel, rv;

        sc = device_get_softc(dev);
        sc->dev = dev;
        node = ofw_bus_get_node(dev);
        type = ofw_bus_search_compatible(dev, compat_data)->ocd_data;

        rv = OF_getencprop(node, "fcs,suspend-voltage-selector", &susp_sel,
                sizeof(susp_sel));
        if (rv <= 0)
                susp_sel = 1;

        switch (type) {
        case FAN53555:
        case SYR827:
        case SYR828:
                if (susp_sel == 1) {
                        sc->live_reg = FAN53555_VSEL0;
                        sc->sleep_reg = FAN53555_VSEL1;
                } else {
                        sc->live_reg = FAN53555_VSEL1;
                        sc->sleep_reg = FAN53555_VSEL0;
                }
                break;
        case TCS4525:
                if (susp_sel == 1) {
                        sc->live_reg = TCS4525_VSEL0;
                        sc->sleep_reg = TCS4525_VSEL1;
                } else {
                        sc->live_reg = TCS4525_VSEL1;
                        sc->sleep_reg = TCS4525_VSEL0;
                }
                break;
        default:
                return (ENXIO);
        }
        if (fan53555_reg_attach(sc, node, type) == NULL)
                device_printf(dev, "cannot attach regulator.\n");

        return (0);
}

static int
fan53555_detach(device_t dev)
{

        /* We cannot detach regulators */
        return (EBUSY);
}

static device_method_t fan53555_methods[] = {
        DEVMETHOD(device_probe,         fan53555_probe),
        DEVMETHOD(device_attach,        fan53555_attach),
        DEVMETHOD(device_detach,        fan53555_detach),

        /* Regdev interface */
        DEVMETHOD(regdev_map,           regdev_default_ofw_map),

        DEVMETHOD_END
};

static DEFINE_CLASS_0(fan53555_pmic, fan53555_driver, fan53555_methods,
    sizeof(struct fan53555_softc));

EARLY_DRIVER_MODULE(fan53555, iicbus, fan53555_driver, 0, 0, BUS_PASS_RESOURCE);
MODULE_VERSION(fan53555, 1);
MODULE_DEPEND(fan53555, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
IICBUS_FDT_PNP_INFO(compat_data);