/*-
 * Copyright (c) 2005-2006 Mitsuru IWASAKI <iwasaki@FreeBSD.org>
 * 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.
 *
 * 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.
 *
 * $FreeBSD: head/sys/dev/acpica/acpi_dock.c 246128 2013-01-30 18:01:20Z sbz $
 */

#include "opt_acpi.h"
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>

#include <contrib/dev/acpica/source/include/acpi.h>
#include <contrib/dev/acpica/source/include/accommon.h>

#include <dev/acpica/acpivar.h>
#include <dev/acpica/acpiio.h>

/* Hooks for the ACPICA debugging infrastructure */
#define _COMPONENT      ACPI_DOCK
ACPI_MODULE_NAME("DOCK")

/* For Docking status */
#define ACPI_DOCK_STATUS_UNKNOWN        -1
#define ACPI_DOCK_STATUS_UNDOCKED       0
#define ACPI_DOCK_STATUS_DOCKED         1

#define ACPI_DOCK_UNLOCK                0 /* Allow device to be ejected */
#define ACPI_DOCK_LOCK                  1 /* Prevent dev from being removed */

#define ACPI_DOCK_ISOLATE               0 /* Isolate from dock connector */
#define ACPI_DOCK_CONNECT               1 /* Connect to dock */

struct acpi_dock_softc {
        int             _sta;
        int             _bdn;
        int             _uid;
        int             status;
        struct sysctl_ctx_list  sysctl_ctx;
        struct sysctl_oid       *sysctl_tree;
};

ACPI_SERIAL_DECL(dock, "ACPI Docking Station");

/*
 * Utility functions
 */

static void
acpi_dock_get_info(device_t dev)
{
        struct acpi_dock_softc *sc;
        ACPI_HANDLE     h;

        sc = device_get_softc(dev);
        h = acpi_get_handle(dev);

        if (ACPI_FAILURE(acpi_GetInteger(h, "_STA", &sc->_sta)))
                sc->_sta = ACPI_DOCK_STATUS_UNKNOWN;
        if (ACPI_FAILURE(acpi_GetInteger(h, "_BDN", &sc->_bdn)))
                sc->_bdn = ACPI_DOCK_STATUS_UNKNOWN;
        if (ACPI_FAILURE(acpi_GetInteger(h, "_UID", &sc->_uid)))
                sc->_uid = ACPI_DOCK_STATUS_UNKNOWN;
        ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev),
                    "_STA: %04x, _BDN: %04x, _UID: %04x\n", sc->_sta,
                    sc->_bdn, sc->_uid);
}

static int
acpi_dock_execute_dck(device_t dev, int dock)
{
        ACPI_HANDLE     h;
        ACPI_OBJECT     argobj;
        ACPI_OBJECT_LIST args;
        ACPI_BUFFER     buf;
        ACPI_OBJECT     retobj;
        ACPI_STATUS     status;

        h = acpi_get_handle(dev);

        argobj.Type = ACPI_TYPE_INTEGER;
        argobj.Integer.Value = dock;
        args.Count = 1;
        args.Pointer = &argobj;
        buf.Pointer = &retobj;
        buf.Length = sizeof(retobj);
        status = AcpiEvaluateObject(h, "_DCK", &args, &buf);

        /*
         * When _DCK is called with 0, OSPM will ignore the return value.
         */
        if (dock == ACPI_DOCK_ISOLATE)
                return (0);

        /* If _DCK returned 1, the request succeeded. */
        if (ACPI_SUCCESS(status) && retobj.Type == ACPI_TYPE_INTEGER &&
            retobj.Integer.Value == 1)
                return (0);

        return (-1);
}

/* Lock devices while docked to prevent surprise removal. */
static void
acpi_dock_execute_lck(device_t dev, int lock)
{
        ACPI_HANDLE     h;

        h = acpi_get_handle(dev);
        acpi_SetInteger(h, "_LCK", lock);
}

/* Eject a device (i.e., motorized). */
static int
acpi_dock_execute_ejx(device_t dev, int eject, int state)
{
        ACPI_HANDLE     h;
        ACPI_STATUS     status;
        char            ejx[5];

        h = acpi_get_handle(dev);
        ksnprintf(ejx, sizeof(ejx), "_EJ%d", state);
        status = acpi_SetInteger(h, ejx, eject);
        if (ACPI_SUCCESS(status))
                return (0);

        return (-1);
}

/* Find dependent devices.  When their parent is removed, so are they. */
static int
acpi_dock_is_ejd_device(ACPI_HANDLE dock_handle, ACPI_HANDLE handle)
{
        int             ret;
        ACPI_STATUS     ret_status;
        ACPI_BUFFER     ejd_buffer;
        ACPI_OBJECT     *obj;

        ret = 0;

        ejd_buffer.Pointer = NULL;
        ejd_buffer.Length = ACPI_ALLOCATE_BUFFER;
        ret_status = AcpiEvaluateObject(handle, "_EJD", NULL, &ejd_buffer);
        if (ACPI_FAILURE(ret_status))
                goto out;

        obj = (ACPI_OBJECT *)ejd_buffer.Pointer;
        if (dock_handle == acpi_GetReference(NULL, obj))
                ret = 1;

out:
        if (ejd_buffer.Pointer != NULL)
                AcpiOsFree(ejd_buffer.Pointer);

        return (ret);
}

/*
 * Docking functions
 */

static void
acpi_dock_attach_later(void *context)
{
        device_t        dev;

        dev = (device_t)context;

        if (!device_is_enabled(dev))
                device_enable(dev);

        lwkt_gettoken(&acpi_token);
        device_probe_and_attach(dev);
        lwkt_reltoken(&acpi_token);
}

static ACPI_STATUS
acpi_dock_insert_child(ACPI_HANDLE handle, UINT32 level, void *context,
    void **status)
{
        device_t        dock_dev, dev;
        ACPI_HANDLE     dock_handle;

        dock_dev = (device_t)context;
        dock_handle = acpi_get_handle(dock_dev);

        if (!acpi_dock_is_ejd_device(dock_handle, handle))
                goto out;

        ACPI_VPRINT(dock_dev, acpi_device_get_parent_softc(dock_dev),
                    "inserting device for %s\n", acpi_name(handle));

#if 0
        /*
         * If the system boot up w/o Docking, the devices under the dock
         * still un-initialized, also control methods such as _INI, _STA
         * are not executed.
         * Normal devices are initialized at booting by calling
         * AcpiInitializeObjects(), however the devices under the dock
         * need to be initialized here on the scheme of ACPICA.
         */
        ACPI_INIT_WALK_INFO     Info;

        AcpiNsWalkNamespace(ACPI_TYPE_ANY, handle,
            100, TRUE, AcpiNsInitOneDevice, NULL, &Info, NULL);
#endif

        dev = acpi_get_device(handle);
        if (dev == NULL) {
                device_printf(dock_dev, "error: %s has no associated device\n",
                    acpi_name(handle));
                goto out;
        }

        AcpiOsExecute(OSL_NOTIFY_HANDLER, acpi_dock_attach_later, dev);

out:
        return (AE_OK);
}

static void
acpi_dock_insert_children(device_t dev)
{
        ACPI_STATUS     status;
        ACPI_HANDLE     sb_handle;

        status = AcpiGetHandle(ACPI_ROOT_OBJECT, "\\_SB_", &sb_handle);
        if (ACPI_SUCCESS(status)) {
                AcpiWalkNamespace(ACPI_TYPE_DEVICE, sb_handle,
                    100, acpi_dock_insert_child, NULL, dev, NULL);
        }
}

static void
acpi_dock_insert(device_t dev)
{
        struct acpi_dock_softc *sc;

        ACPI_SERIAL_ASSERT(dock);

        sc = device_get_softc(dev);

        if (sc->status == ACPI_DOCK_STATUS_UNDOCKED ||
            sc->status == ACPI_DOCK_STATUS_UNKNOWN) {
                acpi_dock_execute_lck(dev, ACPI_DOCK_LOCK);
                if (acpi_dock_execute_dck(dev, ACPI_DOCK_CONNECT) != 0) {
                        device_printf(dev, "_DCK failed\n");
                        return;
                }

                if (!cold)
                        acpi_dock_insert_children(dev);
                sc->status = ACPI_DOCK_STATUS_DOCKED;
        }
}

/*
 * Undock
 */

static ACPI_STATUS
acpi_dock_eject_child(ACPI_HANDLE handle, UINT32 level, void *context,
    void **status)
{
        device_t        dock_dev, dev;
        ACPI_HANDLE     dock_handle;

        dock_dev = *(device_t *)context;
        dock_handle = acpi_get_handle(dock_dev);

        if (!acpi_dock_is_ejd_device(dock_handle, handle))
                goto out;

        ACPI_VPRINT(dock_dev, acpi_device_get_parent_softc(dock_dev),
            "ejecting device for %s\n", acpi_name(handle));

        dev = acpi_get_device(handle);
        if (dev != NULL && device_is_attached(dev)) {
                lwkt_gettoken(&acpi_token);
                device_detach(dev);
                lwkt_reltoken(&acpi_token);
        }

        acpi_SetInteger(handle, "_EJ0", 0);
out:
        return (AE_OK);
}

static void
acpi_dock_eject_children(device_t dev)
{
        ACPI_HANDLE     sb_handle;
        ACPI_STATUS     status;

        status = AcpiGetHandle(ACPI_ROOT_OBJECT, "\\_SB_", &sb_handle);
        if (ACPI_SUCCESS(status)) {
                AcpiWalkNamespace(ACPI_TYPE_DEVICE, sb_handle,
                    100, acpi_dock_eject_child, NULL, &dev, NULL);
        }
}

static void
acpi_dock_removal(device_t dev)
{
        struct acpi_dock_softc *sc;

        ACPI_SERIAL_ASSERT(dock);

        sc = device_get_softc(dev);
        if (sc->status == ACPI_DOCK_STATUS_DOCKED ||
            sc->status == ACPI_DOCK_STATUS_UNKNOWN) {
                acpi_dock_eject_children(dev);
                if (acpi_dock_execute_dck(dev, ACPI_DOCK_ISOLATE) != 0)
                        return;

                acpi_dock_execute_lck(dev, ACPI_DOCK_UNLOCK);

                if (acpi_dock_execute_ejx(dev, 1, 0) != 0) {
                        device_printf(dev, "_EJ0 failed\n");
                        return;
                }

                sc->status = ACPI_DOCK_STATUS_UNDOCKED;
        }

        acpi_dock_get_info(dev);
        if (sc->_sta != 0)
                device_printf(dev, "mechanical failure (%#x).\n", sc->_sta);
}

/*
 * Device/Bus check
 */

static void
acpi_dock_device_check(device_t dev)
{
        struct acpi_dock_softc *sc;

        ACPI_SERIAL_ASSERT(dock);

        sc = device_get_softc(dev);
        acpi_dock_get_info(dev);

        /*
         * If the _STA method indicates 'present' and 'functioning', the
         * system is docked.  If _STA does not exist for this device, it
         * is always present.
         */
        if (sc->_sta == ACPI_DOCK_STATUS_UNKNOWN ||
            ACPI_DEVICE_PRESENT(sc->_sta))
                acpi_dock_insert(dev);
        else if (sc->_sta == 0)
                acpi_dock_removal(dev);
}

/*
 * Notify Handler
 */

static void
acpi_dock_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
{
        device_t        dev;

        dev = (device_t) context;
        ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev),
                    "got notification %#x\n", notify);

        ACPI_SERIAL_BEGIN(dock);
        switch (notify) {
        case ACPI_NOTIFY_BUS_CHECK:
        case ACPI_NOTIFY_DEVICE_CHECK:
                acpi_dock_device_check(dev);
                break;
        case ACPI_NOTIFY_EJECT_REQUEST:
                acpi_dock_removal(dev);
                break;
        default:
                device_printf(dev, "unknown notify: %#x\n", notify);
                break;
        }
        ACPI_SERIAL_END(dock);
}

static int
acpi_dock_status_sysctl(SYSCTL_HANDLER_ARGS)
{
        struct acpi_dock_softc *sc;
        device_t        dev;
        int             status, err;

        dev = (device_t)arg1;

        sc = device_get_softc(dev);
        status = sc->status;

        ACPI_SERIAL_BEGIN(dock);
        err = sysctl_handle_int(oidp, &status, 0, req);
        if (err != 0 || req->newptr == NULL)
                goto out;

        if (status != ACPI_DOCK_STATUS_UNDOCKED &&
            status != ACPI_DOCK_STATUS_DOCKED) {
                err = EINVAL;
                goto out;
        }

        if (status == sc->status)
                goto out;

        switch (status) {
        case ACPI_DOCK_STATUS_UNDOCKED:
                acpi_dock_removal(dev);
                break;
        case ACPI_DOCK_STATUS_DOCKED:
                acpi_dock_device_check(dev);
                break;
        default:
                err = EINVAL;
                break;
        }
out:
        ACPI_SERIAL_END(dock);
        return (err);
}

static int
acpi_dock_probe(device_t dev)
{
        ACPI_HANDLE     h, tmp;

        h = acpi_get_handle(dev);
        if (acpi_disabled("dock") ||
            ACPI_FAILURE(AcpiGetHandle(h, "_DCK", &tmp)))
                return (ENXIO);

        device_set_desc(dev, "ACPI Docking Station");

        /*
         * XXX Somewhere else in the kernel panics on "sysctl kern" if we
         * return a negative value here (reprobe ok).
         */
        return (0);
}

static int
acpi_dock_attach(device_t dev)
{
        struct acpi_softc *acpi_sc;
        struct acpi_dock_softc *sc;
        ACPI_HANDLE     h;

        sc = device_get_softc(dev);
        h = acpi_get_handle(dev);
        if (sc == NULL || h == NULL)
                return (ENXIO);

        sc->status = ACPI_DOCK_STATUS_UNKNOWN;

        AcpiEvaluateObject(h, "_INI", NULL, NULL);

        ACPI_SERIAL_INIT(dock);
        ACPI_SERIAL_BEGIN(dock);

        acpi_dock_device_check(dev);

        /* Get the sysctl tree */
        acpi_sc = acpi_device_get_parent_softc(dev);
        sysctl_ctx_init(&sc->sysctl_ctx);
        sc->sysctl_tree = SYSCTL_ADD_NODE(&sc->sysctl_ctx,
            SYSCTL_CHILDREN(acpi_sc->acpi_sysctl_tree),
            OID_AUTO, "dock", CTLFLAG_RD, 0, "");

        SYSCTL_ADD_INT(&sc->sysctl_ctx,
                SYSCTL_CHILDREN(sc->sysctl_tree),
                OID_AUTO, "_sta", CTLFLAG_RD,
                &sc->_sta, 0, "Dock _STA");
        SYSCTL_ADD_INT(&sc->sysctl_ctx,
                SYSCTL_CHILDREN(sc->sysctl_tree),
                OID_AUTO, "_bdn", CTLFLAG_RD,
                &sc->_bdn, 0, "Dock _BDN");
        SYSCTL_ADD_INT(&sc->sysctl_ctx,
                SYSCTL_CHILDREN(sc->sysctl_tree),
                OID_AUTO, "_uid", CTLFLAG_RD,
                &sc->_uid, 0, "Dock _UID");
        SYSCTL_ADD_PROC(&sc->sysctl_ctx,
                SYSCTL_CHILDREN(sc->sysctl_tree),
                OID_AUTO, "status",
                CTLTYPE_INT|CTLFLAG_RW, dev, 0,
                acpi_dock_status_sysctl, "I",
                "Dock/Undock operation");

        ACPI_SERIAL_END(dock);

        AcpiInstallNotifyHandler(h, ACPI_ALL_NOTIFY,
                                 acpi_dock_notify_handler, dev);

        return (0);
}

static int
acpi_dock_detach(device_t dev)
{
        struct acpi_dock_softc *sc;

        sc = device_get_softc(dev);
        sysctl_ctx_free(&sc->sysctl_ctx);

        return (0);
}

static device_method_t acpi_dock_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe, acpi_dock_probe),
        DEVMETHOD(device_attach, acpi_dock_attach),
        DEVMETHOD(device_detach, acpi_dock_detach),

        DEVMETHOD_END
};

static driver_t acpi_dock_driver = {
        "acpi_dock",
        acpi_dock_methods,
        sizeof(struct acpi_dock_softc),
};

static devclass_t acpi_dock_devclass;

DRIVER_MODULE(acpi_dock, acpi, acpi_dock_driver, acpi_dock_devclass, NULL, NULL);
MODULE_DEPEND(acpi_dock, acpi, 1, 1, 1);