/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * 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/systm.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 <dev/iicbus/pmic/act8846.h>

#include "regdev_if.h"

MALLOC_DEFINE(M_ACT8846_REG, "ACT8846 regulator", "ACT8846 power regulator");

#if 0
#define dprintf(sc, format, arg...)
        device_printf(sc->base_sc->dev, "%s: " format, __func__, arg) */
#else
#define dprintf(sc, format, arg...)
#endif

enum act8846_reg_id {
        ACT8846_REG_ID_REG1,
        ACT8846_REG_ID_REG2,
        ACT8846_REG_ID_REG3,
        ACT8846_REG_ID_REG4,
        ACT8846_REG_ID_REG5,
        ACT8846_REG_ID_REG6,
        ACT8846_REG_ID_REG7,
        ACT8846_REG_ID_REG8,
        ACT8846_REG_ID_REG9,
        ACT8846_REG_ID_REG10,
        ACT8846_REG_ID_REG11,
        ACT8846_REG_ID_REG12,
        ACT8846_REG_ID_REG13,
};

struct act8846_regdef {
        intptr_t                id;             /* ID */
        char                    *name;          /* Regulator name */
        char                    *supply_name;   /* Source property name */
        uint8_t                 enable_reg;
        uint8_t                 enable_mask;
        uint8_t                 voltage_reg;
        uint8_t                 voltage_mask;
        struct regulator_range  *ranges;
        int                     nranges;
};
struct act8846_softc;

struct act8846_reg_sc {
        struct regnode          *regnode;
        struct act8846_softc    *base_sc;
        struct act8846_regdef   *def;
        phandle_t               xref;
        struct regnode_std_param *param;
};


static struct regulator_range act8846_ranges[] = {
        REG_RANGE_INIT(  0, 23,  600000, 25000),
        REG_RANGE_INIT( 24, 47, 1200000, 50000),
        REG_RANGE_INIT( 48, 64, 2400000, 100000),
};

static struct act8846_regdef act8846_regdefs[] = {
        {
                .id = ACT8846_REG_ID_REG1,
                .name = "REG1",
                .supply_name = "vp1",
                .enable_reg = ACT8846_REG1_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
        },
        {
                .id = ACT8846_REG_ID_REG2,
                .name = "REG2",
                .supply_name = "vp2",
                .enable_reg = ACT8846_REG2_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
                .voltage_reg = ACT8846_REG2_VSET0,
                .voltage_mask = ACT8846_VSEL_MASK,
                .ranges = act8846_ranges,
                .nranges = nitems(act8846_ranges),
        },
        {
                .id = ACT8846_REG_ID_REG3,
                .name = "REG3",
                .supply_name = "vp3",
                .enable_reg = ACT8846_REG3_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
                .voltage_reg = ACT8846_REG3_VSET0,
                .voltage_mask = ACT8846_VSEL_MASK,
                .ranges = act8846_ranges,
                .nranges = nitems(act8846_ranges),
        },
        {
                .id = ACT8846_REG_ID_REG4,
                .name = "REG4",
                .supply_name = "vp4",
                .enable_reg = ACT8846_REG4_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
                .voltage_reg = ACT8846_REG4_VSET0,
                .voltage_mask = ACT8846_VSEL_MASK,
                .ranges = act8846_ranges,
                .nranges = nitems(act8846_ranges),
        },
        {
                .id = ACT8846_REG_ID_REG5,
                .name = "REG5",
                .supply_name = "inl1",
                .enable_reg = ACT8846_REG5_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
                .voltage_reg = ACT8846_REG5_VSET,
                .voltage_mask = ACT8846_VSEL_MASK,
                .ranges = act8846_ranges,
                .nranges = nitems(act8846_ranges),
        },
        {
                .id = ACT8846_REG_ID_REG6,
                .name = "REG6",
                .supply_name = "inl1",
                .enable_reg = ACT8846_REG6_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
                .voltage_reg = ACT8846_REG6_VSET,
                .voltage_mask = ACT8846_VSEL_MASK,
                .ranges = act8846_ranges,
                .nranges = nitems(act8846_ranges),
        },
        {
                .id = ACT8846_REG_ID_REG7,
                .name = "REG7",
                .supply_name = "inl1",
                .enable_reg = ACT8846_REG7_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
                .voltage_reg = ACT8846_REG7_VSET,
                .voltage_mask = ACT8846_VSEL_MASK,
                .ranges = act8846_ranges,
                .nranges = nitems(act8846_ranges),
        },
        {
                .id = ACT8846_REG_ID_REG8,
                .name = "REG8",
                .supply_name = "inl2",
                .enable_reg = ACT8846_REG8_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
                .voltage_reg = ACT8846_REG8_VSET,
                .voltage_mask = ACT8846_VSEL_MASK,
                .ranges = act8846_ranges,
                .nranges = nitems(act8846_ranges),
        },
        {
                .id = ACT8846_REG_ID_REG9,
                .name = "REG9",
                .supply_name = "inl2",
                .enable_reg = ACT8846_REG9_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
                .voltage_reg = ACT8846_REG9_VSET,
                .voltage_mask = ACT8846_VSEL_MASK,
                .ranges = act8846_ranges,
                .nranges = nitems(act8846_ranges),
        },
        {
                .id = ACT8846_REG_ID_REG10,
                .name = "REG10",
                .supply_name = "inl3",
                .enable_reg = ACT8846_REG10_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
                .voltage_reg = ACT8846_REG10_VSET,
                .voltage_mask = ACT8846_VSEL_MASK,
                .ranges = act8846_ranges,
                .nranges = nitems(act8846_ranges),
        },
        {
                .id = ACT8846_REG_ID_REG11,
                .name = "REG11",
                .supply_name = "inl3",
                .enable_reg = ACT8846_REG11_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
                .voltage_reg = ACT8846_REG11_VSET,
                .voltage_mask = ACT8846_VSEL_MASK,
                .ranges = act8846_ranges,
                .nranges = nitems(act8846_ranges),
        },
        {
                .id = ACT8846_REG_ID_REG12,
                .name = "REG12",
                .supply_name = "inl3",
                .enable_reg = ACT8846_REG12_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
                .voltage_reg = ACT8846_REG12_VSET,
                .voltage_mask = ACT8846_VSEL_MASK,
                .ranges = act8846_ranges,
                .nranges = nitems(act8846_ranges),
        },
        {
                .id = ACT8846_REG_ID_REG13,
                .name = "REG13",
                .supply_name = "inl1",
                .enable_reg = ACT8846_REG13_CTRL,
                .enable_mask = ACT8846_CTRL_ENA,
        },
};

static int
act8846_read_sel(struct act8846_reg_sc *sc, uint8_t *sel)
{
        int rv;

        rv = RD1(sc->base_sc, sc->def->voltage_reg, sel);
        if (rv != 0)
                return (rv);
        *sel &= sc->def->voltage_mask;
        *sel >>= ffs(sc->def->voltage_mask) - 1;
        return (0);
}

static int
act8846_write_sel(struct act8846_reg_sc *sc, uint8_t sel)
{
        int rv;

        sel <<= ffs(sc->def->voltage_mask) - 1;
        sel &= sc->def->voltage_mask;

        rv = RM1(sc->base_sc, sc->def->voltage_reg,
            sc->def->voltage_mask, sel);
        if (rv != 0)
                return (rv);
        return (rv);
}

static int
act8846_regnode_init(struct regnode *regnode)
{
        return (0);
}

static int
act8846_regnode_enable(struct regnode *regnode, bool enable, int *udelay)
{
        struct act8846_reg_sc *sc;
        int rv;

        sc = regnode_get_softc(regnode);

        dprintf(sc, "%sabling regulator %s\n",
            enable ? "En" : "Dis",
            sc->def->name);
        rv = RM1(sc->base_sc, sc->def->enable_reg,
            sc->def->enable_mask, enable ? sc->def->enable_mask: 0);
        *udelay = sc->param->enable_delay;

        return (rv);
}

static int
act8846_regnode_set_voltage(struct regnode *regnode, int min_uvolt,
    int max_uvolt, int *udelay)
{
        struct act8846_reg_sc *sc;
        uint8_t sel;
        int uvolt, rv;

        sc = regnode_get_softc(regnode);

        if (sc->def->ranges == NULL)
                return (ENXIO);

        dprintf(sc, "Setting %s to %d<->%d uvolts\n",
            sc->def->name,
            min_uvolt,
            max_uvolt);
        rv = regulator_range_volt_to_sel8(sc->def->ranges, sc->def->nranges,
            min_uvolt, max_uvolt, &sel);
        if (rv != 0)
                return (rv);
        *udelay = sc->param->ramp_delay;
        rv = act8846_write_sel(sc, sel);

        act8846_read_sel(sc, &sel);
        regulator_range_sel8_to_volt(sc->def->ranges, sc->def->nranges,
            sel, &uvolt);
        dprintf(sc, "Regulator %s set to %d uvolt\n", sc->def->name,
            uvolt);

        return (rv);
}

static int
act8846_regnode_get_voltage(struct regnode *regnode, int *uvolt)
{
        struct act8846_reg_sc *sc;
        uint8_t sel;
        int rv;

        sc = regnode_get_softc(regnode);

        if (sc->def->ranges == NULL) {
                if (sc->def->id == ACT8846_REG_ID_REG13) {
                        *uvolt = 1800000;
                        return (0);
                }
                return (ENXIO);
        }

        rv = act8846_read_sel(sc, &sel);
        if (rv != 0)
                return (rv);
        rv = regulator_range_sel8_to_volt(sc->def->ranges, sc->def->nranges,
            sel, uvolt);
        dprintf(sc, "Regulator %s is at %d uvolt\n", sc->def->name,
            *uvolt);

        return (rv);
}

static regnode_method_t act8846_regnode_methods[] = {
        /* Regulator interface */
        REGNODEMETHOD(regnode_init,             act8846_regnode_init),
        REGNODEMETHOD(regnode_enable,           act8846_regnode_enable),
        REGNODEMETHOD(regnode_set_voltage,      act8846_regnode_set_voltage),
        REGNODEMETHOD(regnode_get_voltage,      act8846_regnode_get_voltage),
        REGNODEMETHOD_END
};
DEFINE_CLASS_1(act8846_regnode, act8846_regnode_class, act8846_regnode_methods,
    sizeof(struct act8846_reg_sc), regnode_class);

static int
act8846_fdt_parse(struct act8846_softc *sc, phandle_t pnode, phandle_t node,
    struct act8846_regdef *def, struct regnode_init_def *init_def)
{
        int rv;
        phandle_t supply_node;
        char prop_name[64]; /* Maximum OFW property name length. */

        rv = regulator_parse_ofw_stdparam(sc->dev, node, init_def);

        /* Get parent supply. */
        if (def->supply_name == NULL)
                 return (0);

        snprintf(prop_name, sizeof(prop_name), "%s-supply",
            def->supply_name);
        rv = OF_getencprop(pnode, prop_name, &supply_node,
            sizeof(supply_node));
        if (rv <= 0)
                return (rv);
        supply_node = OF_node_from_xref(supply_node);
        rv = OF_getprop_alloc(supply_node, "regulator-name",
            (void **)&init_def->parent_name);
        if (rv <= 0)
                init_def->parent_name = NULL;
        return (0);
}

static struct act8846_reg_sc *
act8846_attach(struct act8846_softc *sc, phandle_t pnode, phandle_t node,
    struct act8846_regdef *def)
{
        struct act8846_reg_sc *reg_sc;
        struct regnode_init_def initdef;
        struct regnode *regnode;

        memset(&initdef, 0, sizeof(initdef));
        if (act8846_fdt_parse(sc, pnode, node, def, &initdef) != 0) {
                device_printf(sc->dev, "cannot parse FDT data for regulator\n");
                return (NULL);
        }
        initdef.id = def->id;
        initdef.ofw_node = node;

        regnode = regnode_create(sc->dev, &act8846_regnode_class, &initdef);
        if (regnode == NULL) {
                device_printf(sc->dev, "cannot create regulator\n");
                return (NULL);
        }

        reg_sc = regnode_get_softc(regnode);
        reg_sc->base_sc = sc;
        reg_sc->def = def;
        reg_sc->xref = OF_xref_from_node(node);
        reg_sc->param = regnode_get_stdparam(regnode);

        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);
}


int
act8846_regulator_attach(struct act8846_softc *sc, phandle_t node)
{
        struct act8846_reg_sc *reg;
        phandle_t child, rnode;
        int i;

        rnode = ofw_bus_find_child(node, "regulators");
        if (rnode <= 0) {
                device_printf(sc->dev, " Cannot find regulators subnode\n");
                return (ENXIO);
        }

        /* ACT8846 specific definitio. */
        sc->nregs = nitems(act8846_regdefs);
        sc->regs = malloc(sizeof(struct act8846_reg_sc *) * sc->nregs,
            M_ACT8846_REG, M_WAITOK | M_ZERO);


        /* Attach all known regulators if exist in DT. */
        for (i = 0; i < sc->nregs; i++) {
                child = ofw_bus_find_child(rnode, act8846_regdefs[i].name);
                if (child == 0) {
                        if (bootverbose)
                                device_printf(sc->dev,
                                    "Regulator %s missing in DT\n",
                                    act8846_regdefs[i].name);
                        continue;
                }
                reg = act8846_attach(sc, node, child, act8846_regdefs + i);
                if (reg == NULL) {
                        device_printf(sc->dev, "Cannot attach regulator: %s\n",
                            act8846_regdefs[i].name);
                        return (ENXIO);
                }
                sc->regs[i] = reg;
        }
        return (0);
}

int
act8846_regulator_map(device_t dev, phandle_t xref, int ncells,
    pcell_t *cells, int *num)
{
        struct act8846_softc *sc;
        int i;

        sc = device_get_softc(dev);
        for (i = 0; i < sc->nregs; i++) {
                if (sc->regs[i] == NULL)
                        continue;
                if (sc->regs[i]->xref == xref) {
                        *num = sc->regs[i]->def->id;
                        return (0);
                }
        }
        return (ENXIO);
}