/*
 * Copyright 2013, Jérôme Duval, korli@users.berlios.de.
 *
 * Distributed under the terms of the MIT License.
 */


#include <ACPI.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>


#define ACPI_AC_MODULE_NAME "drivers/power/acpi_ac/driver_v1"

#define ACPI_AC_DEVICE_MODULE_NAME "drivers/power/acpi_ac/device_v1"

/* Base Namespace devices are published to */
#define ACPI_AC_BASENAME "power/acpi_ac/%d"

// name of pnp generator of path ids
#define ACPI_AC_PATHID_GENERATOR "acpi_ac/path_id"

#define TRACE_AC
#ifdef TRACE_AC
#       define TRACE(x...) dprintf("acpi_ac: " x)
#else
#       define TRACE(x...)
#endif
#define ERROR(x...)     dprintf("acpi_ac: " x)

static device_manager_info *sDeviceManager;


typedef struct acpi_ns_device_info {
        device_node *node;
        acpi_device_module_info *acpi;
        acpi_device acpi_cookie;
        uint8 last_status;
} acpi_ac_device_info;


static void
acpi_ac_update_status(acpi_ac_device_info* device)
{
        acpi_data buf;
        buf.pointer = NULL;
        buf.length = ACPI_ALLOCATE_BUFFER;

        if (device->acpi->evaluate_method(device->acpi_cookie, "_PSR", NULL, &buf) != B_OK
                || buf.pointer == NULL
                || ((acpi_object_type*)buf.pointer)->object_type != ACPI_TYPE_INTEGER) {
                ERROR("couldn't get status\n");
        } else {
                acpi_object_type* object = (acpi_object_type*)buf.pointer;
                device->last_status = object->integer.integer;
                TRACE("status %d\n", device->last_status);
        }
        free(buf.pointer);
}


static void
acpi_ac_notify_handler(acpi_handle device, uint32 value, void *context)
{
        if (value != 0x80) {
                dprintf("acpi_ac: unknown notification (%d)\n", value);
                return;
        }

        acpi_ac_device_info* dev = (acpi_ac_device_info*) context;
        acpi_ac_update_status(dev);
}


//      #pragma mark - device module API


static status_t
acpi_ac_init_device(void *driverCookie, void **cookie)
{
        *cookie = driverCookie;
        return B_OK;
}


static void
acpi_ac_uninit_device(void *_cookie)
{

}


static status_t
acpi_ac_open(void *_cookie, const char *path, int flags, void** cookie)
{
        acpi_ac_device_info *device = (acpi_ac_device_info *)_cookie;
        *cookie = device;
        return B_OK;
}


static status_t
acpi_ac_read(void* _cookie, off_t position, void *buf, size_t* num_bytes)
{
        acpi_ac_device_info* device = (acpi_ac_device_info*)_cookie;
        if (*num_bytes < 1)
                return B_IO_ERROR;

        if (position > 0) {
                *num_bytes = 0;
                return B_OK;
        }

        if (user_memcpy(buf, &device->last_status, sizeof(uint8)) < B_OK)
                return B_BAD_ADDRESS;

        *num_bytes = 1;
        return B_OK;
}


static status_t
acpi_ac_write(void* cookie, off_t position, const void* buffer, size_t* num_bytes)
{
        return B_ERROR;
}


static status_t
acpi_ac_control(void* _cookie, uint32 op, void* arg, size_t len)
{
        return B_ERROR;
}


static status_t
acpi_ac_close (void* cookie)
{
        return B_OK;
}


static status_t
acpi_ac_free (void* cookie)
{
        return B_OK;
}


//      #pragma mark - driver module API


static float
acpi_ac_support(device_node *parent)
{
        const char *bus;
        uint32 device_type;
        const char *hid;

        // make sure parent is really the ACPI bus manager
        if (sDeviceManager->get_attr_string(parent, B_DEVICE_BUS, &bus, false))
                return -1;

        if (strcmp(bus, "acpi"))
                return 0.0;

        // check whether it's really a device
        if (sDeviceManager->get_attr_uint32(parent, ACPI_DEVICE_TYPE_ITEM,
                        &device_type, false) != B_OK
                || device_type != ACPI_TYPE_DEVICE) {
                return 0.0;
        }

        // check whether it's an ac device
        if (sDeviceManager->get_attr_string(parent, ACPI_DEVICE_HID_ITEM, &hid,
                false) != B_OK || strcmp(hid, "ACPI0003")) {
                return 0.0;
        }

        dprintf("acpi_ac_support ac device found\n");

        return 0.6;
}


static status_t
acpi_ac_register_device(device_node *node)
{
        device_attr attrs[] = {
                { B_DEVICE_PRETTY_NAME, B_STRING_TYPE, { .string = "ACPI AC" }},
                { NULL }
        };

        return sDeviceManager->register_node(node, ACPI_AC_MODULE_NAME, attrs,
                NULL, NULL);
}


static status_t
acpi_ac_init_driver(device_node *node, void **_driverCookie)
{
        acpi_ac_device_info *device;
        device_node *parent;
        status_t status;

        device = (acpi_ac_device_info *)calloc(1, sizeof(*device));
        if (device == NULL)
                return B_NO_MEMORY;

        device->node = node;

        parent = sDeviceManager->get_parent_node(node);
        sDeviceManager->get_driver(parent, (driver_module_info **)&device->acpi,
                (void **)&device->acpi_cookie);
        sDeviceManager->put_node(parent);

        status = device->acpi->install_notify_handler(device->acpi_cookie,
                ACPI_DEVICE_NOTIFY, acpi_ac_notify_handler, device);
        if (status != B_OK) {
                ERROR("can't install notify handler\n");
        }

        device->last_status = 0;

        acpi_ac_update_status(device);

        *_driverCookie = device;
        return B_OK;
}


static void
acpi_ac_uninit_driver(void *driverCookie)
{
        acpi_ac_device_info *device = (acpi_ac_device_info *)driverCookie;

        device->acpi->remove_notify_handler(device->acpi_cookie,
                ACPI_DEVICE_NOTIFY, acpi_ac_notify_handler);

        free(device);
}


static status_t
acpi_ac_register_child_devices(void *driverCookie)
{
        acpi_ac_device_info *device = (acpi_ac_device_info *)driverCookie;
        int path_id;
        char name[B_DEV_NAME_LENGTH];

        path_id = sDeviceManager->create_id(ACPI_AC_PATHID_GENERATOR);
        if (path_id < 0) {
                ERROR("register_child_devices: couldn't create a path_id\n");
                return B_ERROR;
        }

        snprintf(name, sizeof(name), ACPI_AC_BASENAME, path_id);

        return sDeviceManager->publish_device(device->node, name,
                ACPI_AC_DEVICE_MODULE_NAME);
}


module_dependency module_dependencies[] = {
        { B_DEVICE_MANAGER_MODULE_NAME, (module_info **)&sDeviceManager },
        {}
};


driver_module_info acpi_ac_driver_module = {
        {
                ACPI_AC_MODULE_NAME,
                0,
                NULL
        },

        acpi_ac_support,
        acpi_ac_register_device,
        acpi_ac_init_driver,
        acpi_ac_uninit_driver,
        acpi_ac_register_child_devices,
        NULL,   // rescan
        NULL,   // removed
};


struct device_module_info acpi_ac_device_module = {
        {
                ACPI_AC_DEVICE_MODULE_NAME,
                0,
                NULL
        },

        acpi_ac_init_device,
        acpi_ac_uninit_device,
        NULL,

        acpi_ac_open,
        acpi_ac_close,
        acpi_ac_free,
        acpi_ac_read,
        acpi_ac_write,
        NULL,
        acpi_ac_control,

        NULL,
        NULL
};

module_info *modules[] = {
        (module_info *)&acpi_ac_driver_module,
        (module_info *)&acpi_ac_device_module,
        NULL
};