/*      $NetBSD: j6x0pwr.c,v 1.16 2023/12/20 14:50:02 thorpej Exp $ */

/*
 * Copyright (c) 2003, 2006 Valeriy E. Ushakov
 * All rights reserved.
 *
 * 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.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: j6x0pwr.c,v 1.16 2023/12/20 14:50:02 thorpej Exp $");

#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/device.h>
#include <sys/systm.h>
#include <sys/callout.h>

#include <dev/apm/apmbios.h>

#include <machine/platid.h>
#include <machine/platid_mask.h>
#include <machine/config_hook.h>

#include <sh3/exception.h>
#include <sh3/intcreg.h>
#include <sh3/pfcreg.h>

#include <sh3/dev/adcvar.h>


/* SH7709 PFC bits pertinent to Jornada 6x0 power */
#define PGDR_MAIN_BATTERY_OUT   0x04
#define PGDR_LID_OPEN           0x01
#define PJDR_AC_POWER_OUT       0x10
#define PLDR_BATTERY_CHARGED    0x20


static inline int __attribute__((__always_inline__))
j6x0pwr_battery_is_absent(void)
{

        return  _reg_read_1(SH7709_PGDR) & PGDR_MAIN_BATTERY_OUT;
}

static inline int __attribute__((__always_inline__))
j6x0pwr_ac_is_off(void)
{

        return _reg_read_1(SH7709_PJDR) & PJDR_AC_POWER_OUT;
}


static inline int __attribute__((__always_inline__))
j6x0pwr_is_not_charging(void)
{

        return _reg_read_1(SH7709_PLDR) & PLDR_BATTERY_CHARGED;
}


/* A/D converter channels to get power stats from */
#define ADC_CHANNEL_BATTERY     3 /* main battery */
#define ADC_CHANNEL_BACKUP      4 /* backup battery - we don't report it */
#define ADC_CHANNEL_CHARGE      5 /* we use PLDR_BATTERY_CHARGED instead */

/*
 * Empirical range of battery values.
 * Thanks to Joseph Heenan for measurements.
 */
#define J6X0PWR_BATTERY_MIN             630
#define J6X0PWR_BATTERY_CRITICAL        635
#define J6X0PWR_BATTERY_LOW             645
#define J6X0PWR_BATTERY_FULL            910 /* can be slightly more */


/* Convenience aliases (XXX: should be provided by config_hook.h) */
#define CONFIG_HOOK_BUTTON_PRESSED      ((void *)1)
#define CONFIG_HOOK_BUTTON_RELEASED     ((void *)0)



/* allow only one instance */
static int j6x0pwr_attached = 0;

struct j6x0pwr_softc {
        device_t sc_dev;

        void *sc_ih;
        volatile int sc_poweroff;
};

static int      j6x0pwr_match(device_t, cfdata_t, void *);
static void     j6x0pwr_attach(device_t, device_t, void *);

CFATTACH_DECL_NEW(j6x0pwr, sizeof(struct j6x0pwr_softc),
    j6x0pwr_match, j6x0pwr_attach, NULL, NULL);


static int      j6x0pwr_apm_getpower_hook(void *, int, long, void *);
static int      j6x0pwr_get_battery(void); /* from ADC */

static int      j6x0pwr_intr(void *);
static void     j6x0pwr_sleep(void *);
static int      j6x0pwr_clear_interrupt(void);


static int
j6x0pwr_match(device_t parent, cfdata_t cfp, void *aux)
{

        /*
         * XXX: does platid_mask_MACH_HP_LX matches _JORNADA_6XX too?
         * Is 620 wired similarly?
         */
        if (!platid_match(&platid, &platid_mask_MACH_HP_JORNADA_6XX))
                return 0;

        if (strcmp(cfp->cf_name, "j6x0pwr") != 0)
                return 0;

        /* allow only one instance */
        return !j6x0pwr_attached;
}


static void
j6x0pwr_attach(device_t parent, device_t self, void *aux)
{
        struct j6x0pwr_softc *sc;

        /* XXX: in machdep.c */
        extern void (*__sleep_func)(void *);
        extern void *__sleep_ctx;

        sc = device_private(self);
        sc->sc_dev = self;

        aprint_naive("\n");
        aprint_normal("\n");

        /* allow only one instance */
        j6x0pwr_attached = 1;

        /* arrange for hpcapm to call us when power status is requested */
        config_hook(CONFIG_HOOK_GET, CONFIG_HOOK_ACADAPTER,
                    CONFIG_HOOK_EXCLUSIVE,
                    j6x0pwr_apm_getpower_hook, sc);
        config_hook(CONFIG_HOOK_GET, CONFIG_HOOK_CHARGE,
                    CONFIG_HOOK_EXCLUSIVE,
                    j6x0pwr_apm_getpower_hook, sc);
        config_hook(CONFIG_HOOK_GET, CONFIG_HOOK_BATTERYVAL,
                    CONFIG_HOOK_EXCLUSIVE,
                    j6x0pwr_apm_getpower_hook, sc);

        /* register sleep function to APM */
        __sleep_func = j6x0pwr_sleep;
        __sleep_ctx = sc;

        sc->sc_poweroff = 0;

        /* drain the old interrupt */
        j6x0pwr_clear_interrupt();

        sc->sc_ih = intc_intr_establish(SH7709_INTEVT2_IRQ0, IST_EDGE, IPL_TTY,
            j6x0pwr_intr, sc);

        _reg_write_1(SH7709_PKDR, 0);   /* Green LED on */

        if (!pmf_device_register(self, NULL, NULL))
                aprint_error_dev(self, "unable to establish power handler\n");
}


/*
 * Triggered when the On/Off button is pressed or the lid is closed.
 * The state of the lid is reflected in the bit PGDR[0].
 * Closing the lid can trigger several consecutive interrupts.
 *
 * XXX: Since we don't put the machine to sleep, I have no idea how
 * wakeup interrupt(s) look like.  Need to revisit when software
 * suspend is added to the kernel (which we need to support ACPI).
 */
static int
j6x0pwr_intr(void *arg)
{
        struct j6x0pwr_softc *sc = arg;
        device_t self = sc->sc_dev;
        uint8_t irr0;
        uint8_t pgdr;

        irr0 = j6x0pwr_clear_interrupt();
        if ((irr0 & IRR0_IRQ0) == 0) {
#ifdef DIAGNOSTIC
                aprint_normal_dev(self, "irr0=0x%02x?\n", irr0);
#endif
                return 0;
        }

        pgdr = _reg_read_1(SH7709_PGDR);
        if ((pgdr & PGDR_LID_OPEN) == 0) {
                aprint_normal_dev(self, "lid closed %d\n", sc->sc_poweroff);
                if (sc->sc_poweroff)
                        return 1;
        } else {
                aprint_normal_dev(self, "ON/OFF %d\n", sc->sc_poweroff);
                if (sc->sc_poweroff)
                        sc->sc_poweroff = 0;
        }

        config_hook_call(CONFIG_HOOK_BUTTONEVENT,
                         CONFIG_HOOK_BUTTONEVENT_POWER,
                         CONFIG_HOOK_BUTTON_PRESSED);
        /* fake release */
        config_hook_call(CONFIG_HOOK_BUTTONEVENT,
                         CONFIG_HOOK_BUTTONEVENT_POWER,
                         CONFIG_HOOK_BUTTON_RELEASED);

        return 1;
}


static int
j6x0pwr_clear_interrupt(void)
{
        uint8_t irr0;

        irr0 = _reg_read_1(SH7709_IRR0);
        if (irr0 & IRR0_IRQ0)
                _reg_write_1(SH7709_IRR0, irr0 & ~IRR0_IRQ0);

        return irr0;
}


void
j6x0pwr_sleep(void *arg)
{
        /* splhigh on entry */
        struct j6x0pwr_softc *sc = arg;
        int s;

        /* Reinstall j6x0pwr_intr as a wakeup handler */
        intc_intr_disestablish(sc->sc_ih);
        sc->sc_ih = intc_intr_establish(SH7709_INTEVT2_IRQ0, IST_EDGE, IPL_HIGH,
            j6x0pwr_intr, sc);
        sc->sc_poweroff = 1;
        do {
                /* Disable interrupt except for power button. */
                s = _cpu_intr_resume(IPL_CLOCK << 4);
                _reg_write_1(SH7709_PKDR, 0xff);        /* Green LED off */

                __asm volatile("sleep");

                _reg_write_1(SH7709_PKDR, 0);           /* Green LED on */
                _cpu_intr_resume(s);
        } while (sc->sc_poweroff);

        /* Return to normal power button */
        intc_intr_disestablish(sc->sc_ih);
        sc->sc_ih = intc_intr_establish(SH7709_INTEVT2_IRQ0, IST_EDGE, IPL_TTY,
            j6x0pwr_intr, sc);
        /* splhigh on exit */
}


static int
j6x0pwr_apm_getpower_hook(void *ctx, int type, long id, void *msg)
{
        /* struct j6x0pwr_softc * const sc = ctx; */
        int * const pval = msg;
        int battery, state;

        if (type != CONFIG_HOOK_GET)
                return EINVAL;

        switch (id) {

        case CONFIG_HOOK_ACADAPTER:
                *pval = j6x0pwr_ac_is_off() ? APM_AC_OFF : APM_AC_ON;
                return 0;

        case CONFIG_HOOK_CHARGE:
                if (j6x0pwr_battery_is_absent())
                        state = APM_BATT_FLAG_NO_SYSTEM_BATTERY;
                else {
                        battery = j6x0pwr_get_battery();
                        if (battery < J6X0PWR_BATTERY_CRITICAL)
                                state = APM_BATT_FLAG_CRITICAL;
                        else if (battery < J6X0PWR_BATTERY_LOW)
                                state = APM_BATT_FLAG_LOW;
                        else
                                state = APM_BATT_FLAG_HIGH; /* XXX? */

                        if (!j6x0pwr_is_not_charging())
                                state |= APM_BATT_FLAG_CHARGING;
                }
                *pval = state;
                return 0;

        case CONFIG_HOOK_BATTERYVAL:
                if (j6x0pwr_battery_is_absent())
                        state = 0;
                else {
                        battery = j6x0pwr_get_battery();
                        if (battery > J6X0PWR_BATTERY_FULL)
                                state = 100;
                        else
                                state = 100 * (battery - J6X0PWR_BATTERY_MIN)
                                        / (J6X0PWR_BATTERY_FULL
                                           - J6X0PWR_BATTERY_MIN);
                }
                *pval = state;
                return 0;
        }

        return EINVAL;
}


static int
j6x0pwr_get_battery(void)
{
        int battery;
        int s;

        if (j6x0pwr_battery_is_absent())
                return -1;

        s = spltty();
        battery = adc_sample_channel(ADC_CHANNEL_BATTERY);
        splx(s);

        return battery;
}