ac.c

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/*
 *  acpi_ac.c - ACPI AC Adapter Driver ($Revision: 27 $)
 *
 *  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.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/types.h>
#ifdef CONFIG_ACPI_PROCFS_POWER
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#endif
#include <linux/power_supply.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>

#define PREFIX "ACPI: "

#define ACPI_AC_CLASS           "ac_adapter"
#define ACPI_AC_DEVICE_NAME     "AC Adapter"
#define ACPI_AC_FILE_STATE      "state"
#define ACPI_AC_NOTIFY_STATUS       0x80
#define ACPI_AC_STATUS_OFFLINE      0x00
#define ACPI_AC_STATUS_ONLINE       0x01
#define ACPI_AC_STATUS_UNKNOWN      0xFF

#define _COMPONENT      ACPI_AC_COMPONENT
ACPI_MODULE_NAME("ac");

MODULE_AUTHOR("Paul Diefenbaugh");
MODULE_DESCRIPTION("ACPI AC Adapter Driver");
MODULE_LICENSE("GPL");

#ifdef CONFIG_ACPI_PROCFS_POWER
extern struct proc_dir_entry *acpi_lock_ac_dir(void);
extern void *acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir);
static int acpi_ac_open_fs(struct inode *inode, struct file *file);
#endif

static int acpi_ac_add(struct acpi_device *device);
static int acpi_ac_remove(struct acpi_device *device, int type);
static void acpi_ac_notify(struct acpi_device *device, u32 event);

static const struct acpi_device_id ac_device_ids[] = {
    {"ACPI0003", 0},
    {"", 0},
};
MODULE_DEVICE_TABLE(acpi, ac_device_ids);

#ifdef CONFIG_PM_SLEEP
static int acpi_ac_resume(struct device *dev);
#endif
static SIMPLE_DEV_PM_OPS(acpi_ac_pm, NULL, acpi_ac_resume);

static struct acpi_driver acpi_ac_driver = {
    .name = "ac",
    .class = ACPI_AC_CLASS,
    .ids = ac_device_ids,
    .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
    .ops = {
        .add = acpi_ac_add,
        .remove = acpi_ac_remove,
        .notify = acpi_ac_notify,
        },
    .drv.pm = &acpi_ac_pm,
};

struct acpi_ac {
    struct power_supply charger;
    struct acpi_device * device;
    unsigned long long state;
};

#define to_acpi_ac(x) container_of(x, struct acpi_ac, charger)

#ifdef CONFIG_ACPI_PROCFS_POWER
static const struct file_operations acpi_ac_fops = {
    .owner = THIS_MODULE,
    .open = acpi_ac_open_fs,
    .read = seq_read,
    .llseek = seq_lseek,
    .release = single_release,
};
#endif

/* --------------------------------------------------------------------------
                               AC Adapter Management
   -------------------------------------------------------------------------- */

static int acpi_ac_get_state(struct acpi_ac *ac)
{
    acpi_status status = AE_OK;


    if (!ac)
        return -EINVAL;

    status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL, &ac->state);
    if (ACPI_FAILURE(status)) {
        ACPI_EXCEPTION((AE_INFO, status, "Error reading AC Adapter state"));
        ac->state = ACPI_AC_STATUS_UNKNOWN;
        return -ENODEV;
    }

    return 0;
}

/* --------------------------------------------------------------------------
                            sysfs I/F
   -------------------------------------------------------------------------- */
static int get_ac_property(struct power_supply *psy,
               enum power_supply_property psp,
               union power_supply_propval *val)
{
    struct acpi_ac *ac = to_acpi_ac(psy);

    if (!ac)
        return -ENODEV;

    if (acpi_ac_get_state(ac))
        return -ENODEV;

    switch (psp) {
    case POWER_SUPPLY_PROP_ONLINE:
        val->intval = ac->state;
        break;
    default:
        return -EINVAL;
    }
    return 0;
}

static enum power_supply_property ac_props[] = {
    POWER_SUPPLY_PROP_ONLINE,
};

#ifdef CONFIG_ACPI_PROCFS_POWER
/* --------------------------------------------------------------------------
                              FS Interface (/proc)
   -------------------------------------------------------------------------- */

static struct proc_dir_entry *acpi_ac_dir;

static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
{
    struct acpi_ac *ac = seq->private;


    if (!ac)
        return 0;

    if (acpi_ac_get_state(ac)) {
        seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
        return 0;
    }

    seq_puts(seq, "state:                   ");
    switch (ac->state) {
    case ACPI_AC_STATUS_OFFLINE:
        seq_puts(seq, "off-line\n");
        break;
    case ACPI_AC_STATUS_ONLINE:
        seq_puts(seq, "on-line\n");
        break;
    default:
        seq_puts(seq, "unknown\n");
        break;
    }

    return 0;
}

static int acpi_ac_open_fs(struct inode *inode, struct file *file)
{
    return single_open(file, acpi_ac_seq_show, PDE(inode)->data);
}

static int acpi_ac_add_fs(struct acpi_device *device)
{
    struct proc_dir_entry *entry = NULL;

    printk(KERN_WARNING PREFIX "Deprecated procfs I/F for AC is loaded,"
            " please retry with CONFIG_ACPI_PROCFS_POWER cleared\n");
    if (!acpi_device_dir(device)) {
        acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
                             acpi_ac_dir);
        if (!acpi_device_dir(device))
            return -ENODEV;
    }

    /* 'state' [R] */
    entry = proc_create_data(ACPI_AC_FILE_STATE,
                 S_IRUGO, acpi_device_dir(device),
                 &acpi_ac_fops, acpi_driver_data(device));
    if (!entry)
        return -ENODEV;
    return 0;
}

static int acpi_ac_remove_fs(struct acpi_device *device)
{

    if (acpi_device_dir(device)) {
        remove_proc_entry(ACPI_AC_FILE_STATE, acpi_device_dir(device));

        remove_proc_entry(acpi_device_bid(device), acpi_ac_dir);
        acpi_device_dir(device) = NULL;
    }

    return 0;
}
#endif

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

static void acpi_ac_notify(struct acpi_device *device, u32 event)
{
    struct acpi_ac *ac = acpi_driver_data(device);


    if (!ac)
        return;

    switch (event) {
    default:
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                  "Unsupported event [0x%x]\n", event));
    case ACPI_AC_NOTIFY_STATUS:
    case ACPI_NOTIFY_BUS_CHECK:
    case ACPI_NOTIFY_DEVICE_CHECK:
        acpi_ac_get_state(ac);
        acpi_bus_generate_proc_event(device, event, (u32) ac->state);
        acpi_bus_generate_netlink_event(device->pnp.device_class,
                          dev_name(&device->dev), event,
                          (u32) ac->state);
        acpi_notifier_call_chain(device, event, (u32) ac->state);
        kobject_uevent(&ac->charger.dev->kobj, KOBJ_CHANGE);
    }

    return;
}

static int acpi_ac_add(struct acpi_device *device)
{
    int result = 0;
    struct acpi_ac *ac = NULL;


    if (!device)
        return -EINVAL;

    ac = kzalloc(sizeof(struct acpi_ac), GFP_KERNEL);
    if (!ac)
        return -ENOMEM;

    ac->device = device;
    strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
    strcpy(acpi_device_class(device), ACPI_AC_CLASS);
    device->driver_data = ac;

    result = acpi_ac_get_state(ac);
    if (result)
        goto end;

#ifdef CONFIG_ACPI_PROCFS_POWER
    result = acpi_ac_add_fs(device);
#endif
    if (result)
        goto end;
    ac->charger.name = acpi_device_bid(device);
    ac->charger.type = POWER_SUPPLY_TYPE_MAINS;
    ac->charger.properties = ac_props;
    ac->charger.num_properties = ARRAY_SIZE(ac_props);
    ac->charger.get_property = get_ac_property;
    result = power_supply_register(&ac->device->dev, &ac->charger);
    if (result)
        goto end;

    printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
           acpi_device_name(device), acpi_device_bid(device),
           ac->state ? "on-line" : "off-line");

      end:
    if (result) {
#ifdef CONFIG_ACPI_PROCFS_POWER
        acpi_ac_remove_fs(device);
#endif
        kfree(ac);
    }

    return result;
}

#ifdef CONFIG_PM_SLEEP
static int acpi_ac_resume(struct device *dev)
{
    struct acpi_ac *ac;
    unsigned old_state;

    if (!dev)
        return -EINVAL;

    ac = acpi_driver_data(to_acpi_device(dev));
    if (!ac)
        return -EINVAL;

    old_state = ac->state;
    if (acpi_ac_get_state(ac))
        return 0;
    if (old_state != ac->state)
        kobject_uevent(&ac->charger.dev->kobj, KOBJ_CHANGE);
    return 0;
}
#endif

static int acpi_ac_remove(struct acpi_device *device, int type)
{
    struct acpi_ac *ac = NULL;


    if (!device || !acpi_driver_data(device))
        return -EINVAL;

    ac = acpi_driver_data(device);

    if (ac->charger.dev)
        power_supply_unregister(&ac->charger);
#ifdef CONFIG_ACPI_PROCFS_POWER
    acpi_ac_remove_fs(device);
#endif

    kfree(ac);

    return 0;
}

static int __init acpi_ac_init(void)
{
    int result;

    if (acpi_disabled)
        return -ENODEV;

#ifdef CONFIG_ACPI_PROCFS_POWER
    acpi_ac_dir = acpi_lock_ac_dir();
    if (!acpi_ac_dir)
        return -ENODEV;
#endif

    result = acpi_bus_register_driver(&acpi_ac_driver);
    if (result < 0) {
#ifdef CONFIG_ACPI_PROCFS_POWER
        acpi_unlock_ac_dir(acpi_ac_dir);
#endif
        return -ENODEV;
    }

    return 0;
}

static void __exit acpi_ac_exit(void)
{

    acpi_bus_unregister_driver(&acpi_ac_driver);

#ifdef CONFIG_ACPI_PROCFS_POWER
    acpi_unlock_ac_dir(acpi_ac_dir);
#endif

    return;
}

module_init(acpi_ac_init);
module_exit(acpi_ac_exit);