/*      $NetBSD: smsc.c,v 1.13 2022/06/29 15:56:58 mlelstv Exp $ */

/*-
 * Copyright (c) 2007 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Brett Lymn.
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

/*
 * This is a driver for the Standard Microsystems Corp (SMSC)
 * LPC47B397 "super i/o" chip.  This driver only handles the environment
 * monitoring capabilities of the chip, the other functions will be
 * probed/matched as "normal" PC hardware devices (serial ports, fdc, so on).
 * SMSC has not deigned to release a datasheet for this particular chip
 * (though they do for others they make) so this driver was written from
 * information contained in the comment block for the Linux driver.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: smsc.c,v 1.13 2022/06/29 15:56:58 mlelstv Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/module.h>
#include <sys/bus.h>

#include <dev/isa/isareg.h>
#include <dev/isa/isavar.h>

#include <dev/sysmon/sysmonvar.h>
#include <dev/isa/smscvar.h>

#if defined(LMDEBUG)
#define DPRINTF(x)      do { printf x; } while (0)
#else
#define DPRINTF(x)
#endif

static int      smsc_match(device_t, cfdata_t, void *);
static void     smsc_attach(device_t, device_t, void *);
static int      smsc_detach(device_t, int);

static uint8_t  smsc_readreg(bus_space_tag_t, bus_space_handle_t, int);
static void     smsc_writereg(bus_space_tag_t, bus_space_handle_t, int, int);

static void     smsc_refresh(struct sysmon_envsys *, envsys_data_t *);

CFATTACH_DECL_NEW(smsc, sizeof(struct smsc_softc),
    smsc_match, smsc_attach, smsc_detach, NULL);

/*
 * Probe for the SMSC Super I/O chip
 */
static int
smsc_match(device_t parent, cfdata_t match, void *aux)
{
        bus_space_handle_t ioh;
        struct isa_attach_args *ia = aux;
        int rv;
        uint8_t cr;

        /* Must supply an address */
        if (ia->ia_nio < 1)
                return 0;

        if (ISA_DIRECT_CONFIG(ia))
                return 0;

        if (ia->ia_io[0].ir_addr == ISA_UNKNOWN_PORT)
                return 0;

        if (bus_space_map(ia->ia_iot, ia->ia_io[0].ir_addr, 2, 0, &ioh))
                return 0;

        /* To get the device ID we must enter config mode... */
        bus_space_write_1(ia->ia_iot, ioh, SMSC_ADDR, SMSC_CONFIG_START);

        /* Then select the device id register */
        cr = smsc_readreg(ia->ia_iot, ioh, SMSC_DEVICE_ID);

        /* Exit config mode, apparently this is important to do */
        bus_space_write_1(ia->ia_iot, ioh, SMSC_ADDR, SMSC_CONFIG_END);

        switch (cr) {
        case SMSC_ID_47B397:
        case SMSC_ID_SCH5307NS:
        case SMSC_ID_SCH5317:
                rv = 1;
                break;
        default:
                rv = 0;
                break;
        }

        DPRINTF(("smsc: rv = %d, cr = %x\n", rv, cr));

        bus_space_unmap(ia->ia_iot, ioh, 2);

        if (rv) {
                ia->ia_nio = 1;
                ia->ia_io[0].ir_size = 2;

                ia->ia_niomem = 0;
                ia->ia_nirq = 0;
                ia->ia_ndrq = 0;
        }

        return rv;
}

/*
 * Get the base address for the monitoring registers and set up the
 * sysmon_envsys(9) framework.
 */
static void
smsc_attach(device_t parent, device_t self, void *aux)
{
        struct smsc_softc *sc = device_private(self);
        struct isa_attach_args *ia = aux;
        bus_space_handle_t ioh;
        uint8_t rev, msb, lsb, chipid;
        unsigned address;
        int i;

        sc->sc_iot = ia->ia_iot;

        aprint_naive("\n");

        /* 
         * To attach we need to find the actual Hardware Monitor
         * I/O address space.
         */
        if (bus_space_map(ia->ia_iot, ia->ia_io[0].ir_addr, 2, 0,
            &ioh)) {
                aprint_error(": can't map base i/o space\n");
                return;
        }

        /* Enter config mode */
        bus_space_write_1(ia->ia_iot, ioh, SMSC_ADDR, SMSC_CONFIG_START);

        /* 
         * While we have the base registers mapped, grab the chip
         * revision and device ID.
         */
        rev = smsc_readreg(ia->ia_iot, ioh, SMSC_DEVICE_REVISION);
        chipid = smsc_readreg(ia->ia_iot, ioh, SMSC_DEVICE_ID);

        /* Select the Hardware Monitor LDN */
        smsc_writereg(ia->ia_iot, ioh, SMSC_LOGICAL_DEV_SEL,
            SMSC_LOGICAL_DEVICE);

        /* Read the base address for the registers. */
        msb = smsc_readreg(ia->ia_iot, ioh, SMSC_IO_BASE_MSB);
        lsb = smsc_readreg(ia->ia_iot, ioh, SMSC_IO_BASE_LSB);
        address = (msb << 8) | lsb;

        /* Exit config mode */
        bus_space_write_1(ia->ia_iot, ioh, SMSC_ADDR, SMSC_CONFIG_END);
        bus_space_unmap(ia->ia_iot, ioh, 2);

        /* Map the Hardware Monitor I/O space. */
        if (bus_space_map(ia->ia_iot, address, 2, 0, &sc->sc_ioh)) {
                aprint_error(": can't map register i/o space\n");
                return;
        }

        sc->sc_sme = sysmon_envsys_create();

#define INITSENSOR(index, string, reg, type)                    \
        do {                                                    \
                strlcpy(sc->sc_sensor[index].desc, string,      \
                    sizeof(sc->sc_sensor[index].desc));         \
                sc->sc_sensor[index].units = type;              \
                sc->sc_regs[index] = reg;                       \
                sc->sc_sensor[index].state = ENVSYS_SVALID;     \
        } while (/* CONSTCOND */ 0)

        /* Temperature sensors */
        INITSENSOR(0, "Temp0", SMSC_TEMP1, ENVSYS_STEMP);
        INITSENSOR(1, "Temp1", SMSC_TEMP2, ENVSYS_STEMP);
        INITSENSOR(2, "Temp2", SMSC_TEMP3, ENVSYS_STEMP);
        INITSENSOR(3, "Temp3", SMSC_TEMP4, ENVSYS_STEMP);
        
        /* Fan sensors */
        INITSENSOR(4, "Fan0", SMSC_FAN1_LSB, ENVSYS_SFANRPM);
        INITSENSOR(5, "Fan1", SMSC_FAN2_LSB, ENVSYS_SFANRPM);
        INITSENSOR(6, "Fan2", SMSC_FAN3_LSB, ENVSYS_SFANRPM);
        INITSENSOR(7, "Fan3", SMSC_FAN4_LSB, ENVSYS_SFANRPM);

        for (i = 0; i < SMSC_MAX_SENSORS; i++) {
                sc->sc_sensor[i].state = ENVSYS_SINVALID;
                if (sysmon_envsys_sensor_attach(sc->sc_sme,
                                                &sc->sc_sensor[i])) {
                        sysmon_envsys_destroy(sc->sc_sme);
                        sc->sc_sme = NULL;
                        bus_space_unmap(sc->sc_iot, sc->sc_ioh, 2);
                        return;
                }
        }

        sc->sc_sme->sme_name = device_xname(self);
        sc->sc_sme->sme_cookie = sc;
        sc->sc_sme->sme_refresh = smsc_refresh;

        if ((i = sysmon_envsys_register(sc->sc_sme)) != 0) {
                aprint_error(": unable to register with sysmon (%d)\n", i);
                sysmon_envsys_destroy(sc->sc_sme);
                sc->sc_sme = NULL;
                bus_space_unmap(sc->sc_iot, sc->sc_ioh, 2);
                return;
        }

        switch (chipid) {
        case SMSC_ID_47B397:
                aprint_normal(": SMSC LPC47B397 Super I/O");
                break;
        case SMSC_ID_SCH5307NS:
                aprint_normal(": SMSC SCH5307-NS Super I/O");
                break;
        case SMSC_ID_SCH5317:
                aprint_normal(": SMSC SCH5317 Super I/O");
                break;
        }

        aprint_normal(" (rev %u)\n", rev);
        aprint_normal_dev(self, "Hardware Monitor registers at 0x%04x\n",
            address);
}

static int
smsc_detach(device_t self, int flags)
{
        struct smsc_softc *sc = device_private(self);

        if (sc->sc_sme != NULL)
                sysmon_envsys_unregister(sc->sc_sme);
        bus_space_unmap(sc->sc_iot, sc->sc_ioh, 2);
        return 0;
}

/*
 * Read the value of the given register
 */
static uint8_t
smsc_readreg(bus_space_tag_t iot, bus_space_handle_t ioh, int reg)
{
        bus_space_write_1(iot, ioh, SMSC_ADDR, reg);
        return bus_space_read_1(iot, ioh, SMSC_DATA);
}

/*
 * Write the given value to the given register.
 */
static void
smsc_writereg(bus_space_tag_t iot, bus_space_handle_t ioh, int reg, int val)
{
        bus_space_write_1(iot, ioh, SMSC_ADDR, reg);
        bus_space_write_1(iot, ioh, SMSC_DATA, val);
}

/* convert temperature read from the chip to micro kelvin */
static inline int
smsc_temp2muk(uint8_t t)
{
        int temp=t;

        return temp * 1000000 + 273150000U;
}

/*
 * convert register value read from chip into rpm using:
 *
 * RPM = 60/(Count * 11.111us)
 *
 * 1/1.1111us = 90kHz
 *
 */
static inline int
smsc_reg2rpm(unsigned int r)
{
        unsigned long rpm;

        if (r == 0x0)
                return 0;

        rpm = (90000 * 60) / ((unsigned long) r);
        return (int) rpm;
}

/* min and max temperatures in uK */
#define SMSC_MIN_TEMP_UK ((-127 * 1000000) + 273150000)
#define SMSC_MAX_TEMP_UK ((127 * 1000000) + 273150000)

/*
 * Get the data for the requested sensor, update the sysmon structure
 * with the retrieved value.
 */
static void
smsc_refresh(struct sysmon_envsys *sme, envsys_data_t *edata)
{
        struct smsc_softc *sc = sme->sme_cookie;
        int reg;
        unsigned int rpm;
        uint8_t msb, lsb;

        reg = sc->sc_regs[edata->sensor];

        switch (edata->units) {
        case ENVSYS_STEMP:
                edata->value_cur = 
                    smsc_temp2muk(smsc_readreg(sc->sc_iot, sc->sc_ioh, reg));
                break;

        case ENVSYS_SFANRPM:
                /* reading lsb first locks msb... */
                lsb = smsc_readreg(sc->sc_iot, sc->sc_ioh, reg);
                msb = smsc_readreg(sc->sc_iot, sc->sc_ioh, reg + 1);
                rpm = (msb << 8) | lsb;
                edata->value_cur = smsc_reg2rpm(rpm);
                break;
        }
}

MODULE(MODULE_CLASS_DRIVER, smsc, "sysmon_envsys");

#ifdef _MODULE
#include "ioconf.c"
#endif

static int
smsc_modcmd(modcmd_t cmd, void *opaque)
{
        int error = 0;

        switch (cmd) {
        case MODULE_CMD_INIT:
#ifdef _MODULE
                error = config_init_component(cfdriver_ioconf_smsc,
                    cfattach_ioconf_smsc, cfdata_ioconf_smsc);
#endif
                return error;
        case MODULE_CMD_FINI:
#ifdef _MODULE
                error = config_fini_component(cfdriver_ioconf_smsc,
                    cfattach_ioconf_smsc, cfdata_ioconf_smsc);
#endif
                return error;
        default:
                return ENOTTY;
        }
}