tc1100-wmi.c

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/*
 *  HP Compaq TC1100 Tablet WMI Extras Driver
 *
 *  Copyright (C) 2007 Carlos Corbacho <[email protected]>
 *  Copyright (C) 2004 Jamey Hicks <[email protected]>
 *  Copyright (C) 2001, 2002 Andy Grover <[email protected]>
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or (at
 *  your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/types.h>
#include <acpi/acpi.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#include <linux/platform_device.h>

#define GUID "C364AC71-36DB-495A-8494-B439D472A505"

#define TC1100_INSTANCE_WIRELESS        1
#define TC1100_INSTANCE_JOGDIAL     2

MODULE_AUTHOR("Jamey Hicks, Carlos Corbacho");
MODULE_DESCRIPTION("HP Compaq TC1100 Tablet WMI Extras");
MODULE_LICENSE("GPL");
MODULE_ALIAS("wmi:C364AC71-36DB-495A-8494-B439D472A505");

static struct platform_device *tc1100_device;

struct tc1100_data {
    u32 wireless;
    u32 jogdial;
};

static struct tc1100_data suspend_data;

/* --------------------------------------------------------------------------
                Device Management
   -------------------------------------------------------------------------- */

static int get_state(u32 *out, u8 instance)
{
    u32 tmp;
    acpi_status status;
    struct acpi_buffer result = { ACPI_ALLOCATE_BUFFER, NULL };
    union acpi_object *obj;

    if (!out)
        return -EINVAL;

    if (instance > 2)
        return -ENODEV;

    status = wmi_query_block(GUID, instance, &result);
    if (ACPI_FAILURE(status))
        return -ENODEV;

    obj = (union acpi_object *) result.pointer;
    if (obj && obj->type == ACPI_TYPE_INTEGER) {
        tmp = obj->integer.value;
    } else {
        tmp = 0;
    }

    if (result.length > 0 && result.pointer)
        kfree(result.pointer);

    switch (instance) {
    case TC1100_INSTANCE_WIRELESS:
        *out = (tmp == 3) ? 1 : 0;
        return 0;
    case TC1100_INSTANCE_JOGDIAL:
        *out = (tmp == 1) ? 0 : 1;
        return 0;
    default:
        return -ENODEV;
    }
}

static int set_state(u32 *in, u8 instance)
{
    u32 value;
    acpi_status status;
    struct acpi_buffer input;

    if (!in)
        return -EINVAL;

    if (instance > 2)
        return -ENODEV;

    switch (instance) {
    case TC1100_INSTANCE_WIRELESS:
        value = (*in) ? 1 : 2;
        break;
    case TC1100_INSTANCE_JOGDIAL:
        value = (*in) ? 0 : 1;
        break;
    default:
        return -ENODEV;
    }

    input.length = sizeof(u32);
    input.pointer = &value;

    status = wmi_set_block(GUID, instance, &input);
    if (ACPI_FAILURE(status))
        return -ENODEV;

    return 0;
}

/* --------------------------------------------------------------------------
                FS Interface (/sys)
   -------------------------------------------------------------------------- */

/*
 * Read/ write bool sysfs macro
 */
#define show_set_bool(value, instance) \
static ssize_t \
show_bool_##value(struct device *dev, struct device_attribute *attr, \
    char *buf) \
{ \
    u32 result; \
    acpi_status status = get_state(&result, instance); \
    if (ACPI_SUCCESS(status)) \
        return sprintf(buf, "%d\n", result); \
    return sprintf(buf, "Read error\n"); \
} \
\
static ssize_t \
set_bool_##value(struct device *dev, struct device_attribute *attr, \
    const char *buf, size_t count) \
{ \
    u32 tmp = simple_strtoul(buf, NULL, 10); \
    acpi_status status = set_state(&tmp, instance); \
        if (ACPI_FAILURE(status)) \
            return -EINVAL; \
    return count; \
} \
static DEVICE_ATTR(value, S_IRUGO | S_IWUSR, \
    show_bool_##value, set_bool_##value);

show_set_bool(wireless, TC1100_INSTANCE_WIRELESS);
show_set_bool(jogdial, TC1100_INSTANCE_JOGDIAL);

static struct attribute *tc1100_attributes[] = {
    &dev_attr_wireless.attr,
    &dev_attr_jogdial.attr,
    NULL
};

static struct attribute_group tc1100_attribute_group = {
    .attrs  = tc1100_attributes,
};

/* --------------------------------------------------------------------------
                Driver Model
   -------------------------------------------------------------------------- */

static int __init tc1100_probe(struct platform_device *device)
{
    return sysfs_create_group(&device->dev.kobj, &tc1100_attribute_group);
}


static int __devexit tc1100_remove(struct platform_device *device)
{
    sysfs_remove_group(&device->dev.kobj, &tc1100_attribute_group);

    return 0;
}

#ifdef CONFIG_PM
static int tc1100_suspend(struct device *dev)
{
    int ret;

    ret = get_state(&suspend_data.wireless, TC1100_INSTANCE_WIRELESS);
    if (ret)
        return ret;

    ret = get_state(&suspend_data.jogdial, TC1100_INSTANCE_JOGDIAL);
    if (ret)
        return ret;

    return 0;
}

static int tc1100_resume(struct device *dev)
{
    int ret;

    ret = set_state(&suspend_data.wireless, TC1100_INSTANCE_WIRELESS);
    if (ret)
        return ret;

    ret = set_state(&suspend_data.jogdial, TC1100_INSTANCE_JOGDIAL);
    if (ret)
        return ret;

    return 0;
}

static const struct dev_pm_ops tc1100_pm_ops = {
    .suspend    = tc1100_suspend,
    .resume     = tc1100_resume,
    .freeze     = tc1100_suspend,
    .restore    = tc1100_resume,
};
#endif

static struct platform_driver tc1100_driver = {
    .driver = {
        .name = "tc1100-wmi",
        .owner = THIS_MODULE,
#ifdef CONFIG_PM
        .pm = &tc1100_pm_ops,
#endif
    },
    .remove = __devexit_p(tc1100_remove),
};

static int __init tc1100_init(void)
{
    int error;

    if (!wmi_has_guid(GUID))
        return -ENODEV;

    tc1100_device = platform_device_alloc("tc1100-wmi", -1);
    if (!tc1100_device)
        return -ENOMEM;

    error = platform_device_add(tc1100_device);
    if (error)
        goto err_device_put;

    error = platform_driver_probe(&tc1100_driver, tc1100_probe);
    if (error)
        goto err_device_del;

    pr_info("HP Compaq TC1100 Tablet WMI Extras loaded\n");
    return 0;

 err_device_del:
    platform_device_del(tc1100_device);
 err_device_put:
    platform_device_put(tc1100_device);
    return error;
}

static void __exit tc1100_exit(void)
{
    platform_device_unregister(tc1100_device);
    platform_driver_unregister(&tc1100_driver);
}

module_init(tc1100_init);
module_exit(tc1100_exit);