/*      $OpenBSD: sxits.c,v 1.3 2021/10/24 17:52:27 mpi Exp $   */
/*
 * Copyright (c) 2018 Mark Kettenis <kettenis@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/sensors.h>

#include <machine/intr.h>
#include <machine/bus.h>
#include <machine/fdt.h>

#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_thermal.h>
#include <dev/ofw/fdt.h>

/* Registers */
#define TP_CTRL0                        0x00
#define  TP_CTRL0_ADC_CLK_DIVIDER(x)    (((x) & 0x3) << 20)
#define  TP_CTRL0_FS_DIV(x)             (((x) & 0xf) << 16)
#define  TP_CTRL0_TACQ(x)               ((x) & 0xffff)
#define TP_CTRL1                        0x04
#define  TP_CTRL1_TP_MODE_EN            (1 << 4)
#define TP_CTRL3                        0x0c
#define  TP_CTRL3_FILTER_EN             (1 << 2)
#define  TP_CTRL3_FILTER_TYPE(x)        ((x) & 0x3)
#define TP_TPR                          0x18
#define  TP_TPR_TEMP_EN                 (1 << 16)
#define  TP_TPR_TEMP_PER(x)             ((x) & 0xffff)
#define TEMP_DATA                       0x20

#define HREAD4(sc, reg)                                                 \
        (bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, (reg)))
#define HWRITE4(sc, reg, val)                                           \
        bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, (reg), (val))

struct sxits_softc {
        struct device           sc_dev;
        bus_space_tag_t         sc_iot;
        bus_space_handle_t      sc_ioh;

        uint16_t                sc_offset;
        uint16_t                sc_scale;

        struct ksensor          sc_sensor;
        struct ksensordev       sc_sensordev;

        struct thermal_sensor   sc_ts;
};

int     sxits_match(struct device *, void *, void *);
void    sxits_attach(struct device *, struct device *, void *);

const struct cfattach   sxits_ca = {
        sizeof (struct sxits_softc), sxits_match, sxits_attach
};

struct cfdriver sxits_cd = {
        NULL, "sxits", DV_DULL
};

void    sxits_refresh_sensors(void *);
int32_t sxits_get_temperature(void *, uint32_t *);

int
sxits_match(struct device *parent, void *match, void *aux)
{
        struct fdt_attach_args *faa = aux;

        return (OF_is_compatible(faa->fa_node, "allwinner,sun4i-a10-ts") ||
            OF_is_compatible(faa->fa_node, "allwinner,sun5i-a13-ts"));
}

void
sxits_attach(struct device *parent, struct device *self, void *aux)
{
        struct sxits_softc *sc = (struct sxits_softc *)self;
        struct fdt_attach_args *faa = aux;

        if (faa->fa_nreg < 1) {
                printf(": no registers\n");
                return;
        }

        sc->sc_iot = faa->fa_iot;
        if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr,
            faa->fa_reg[0].size, 0, &sc->sc_ioh)) {
                printf(": can't map registers\n");
                return;
        }

        printf("\n");

        if (OF_is_compatible(faa->fa_node, "allwinner,sun4i-a10-ts")) {
                sc->sc_offset = 1932;
                sc->sc_scale = 133;
        } else {
                sc->sc_offset = 1447;
                sc->sc_scale = 100;
        }

        /* Start data acquisition. */
        HWRITE4(sc, TP_CTRL0, TP_CTRL0_ADC_CLK_DIVIDER(2) |
            TP_CTRL0_FS_DIV(7) | TP_CTRL0_TACQ(63));
        HWRITE4(sc, TP_CTRL1, TP_CTRL1_TP_MODE_EN);
        HWRITE4(sc, TP_CTRL3, TP_CTRL3_FILTER_EN | TP_CTRL3_FILTER_TYPE(1));
        HWRITE4(sc, TP_TPR, TP_TPR_TEMP_EN | TP_TPR_TEMP_PER(800));

        /* Register sensors. */
        strlcpy(sc->sc_sensordev.xname, sc->sc_dev.dv_xname,
            sizeof(sc->sc_sensordev.xname));
        sc->sc_sensor.type = SENSOR_TEMP;
        sc->sc_sensor.flags = SENSOR_FINVALID;
        sensor_attach(&sc->sc_sensordev, &sc->sc_sensor);
        sensordev_install(&sc->sc_sensordev);
        sensor_task_register(sc, sxits_refresh_sensors, 5);

        sc->sc_ts.ts_node = faa->fa_node;
        sc->sc_ts.ts_cookie = sc;
        sc->sc_ts.ts_get_temperature = sxits_get_temperature;
        thermal_sensor_register(&sc->sc_ts);
}

void
sxits_refresh_sensors(void *arg)
{
        struct sxits_softc *sc = arg;
        uint32_t data, temp;

        data = HREAD4(sc, TEMP_DATA);
        if (data == 0) {
                sc->sc_sensor.flags |= SENSOR_FINVALID;
                return;
        }

        temp = (data - sc->sc_offset) * sc->sc_scale;
        sc->sc_sensor.value = temp * 1000 + 273150000;
        sc->sc_sensor.flags &= ~SENSOR_FINVALID;
}

int32_t
sxits_get_temperature(void *cookie, uint32_t *cells)
{
        struct sxits_softc *sc = cookie;
        uint32_t data;

        data = HREAD4(sc, TEMP_DATA);
        if (data == 0)
                return THERMAL_SENSOR_MAX;

        return (data - sc->sc_offset) * sc->sc_scale;
}