button.c

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/*
 *  button.c - ACPI Button Driver
 *
 *  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/init.h>
#include <linux/types.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/input.h>
#include <linux/slab.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>

#define PREFIX "ACPI: "

#define ACPI_BUTTON_CLASS       "button"
#define ACPI_BUTTON_FILE_INFO       "info"
#define ACPI_BUTTON_FILE_STATE      "state"
#define ACPI_BUTTON_TYPE_UNKNOWN    0x00
#define ACPI_BUTTON_NOTIFY_STATUS   0x80

#define ACPI_BUTTON_SUBCLASS_POWER  "power"
#define ACPI_BUTTON_HID_POWER       "PNP0C0C"
#define ACPI_BUTTON_DEVICE_NAME_POWER   "Power Button"
#define ACPI_BUTTON_TYPE_POWER      0x01

#define ACPI_BUTTON_SUBCLASS_SLEEP  "sleep"
#define ACPI_BUTTON_HID_SLEEP       "PNP0C0E"
#define ACPI_BUTTON_DEVICE_NAME_SLEEP   "Sleep Button"
#define ACPI_BUTTON_TYPE_SLEEP      0x03

#define ACPI_BUTTON_SUBCLASS_LID    "lid"
#define ACPI_BUTTON_HID_LID     "PNP0C0D"
#define ACPI_BUTTON_DEVICE_NAME_LID "Lid Switch"
#define ACPI_BUTTON_TYPE_LID        0x05

#define _COMPONENT      ACPI_BUTTON_COMPONENT
ACPI_MODULE_NAME("button");

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

static const struct acpi_device_id button_device_ids[] = {
    {ACPI_BUTTON_HID_LID,    0},
    {ACPI_BUTTON_HID_SLEEP,  0},
    {ACPI_BUTTON_HID_SLEEPF, 0},
    {ACPI_BUTTON_HID_POWER,  0},
    {ACPI_BUTTON_HID_POWERF, 0},
    {"", 0},
};
MODULE_DEVICE_TABLE(acpi, button_device_ids);

static int acpi_button_add(struct acpi_device *device);
static int acpi_button_remove(struct acpi_device *device, int type);
static void acpi_button_notify(struct acpi_device *device, u32 event);

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

static struct acpi_driver acpi_button_driver = {
    .name = "button",
    .class = ACPI_BUTTON_CLASS,
    .ids = button_device_ids,
    .ops = {
        .add = acpi_button_add,
        .remove = acpi_button_remove,
        .notify = acpi_button_notify,
    },
    .drv.pm = &acpi_button_pm,
};

struct acpi_button {
    unsigned int type;
    struct input_dev *input;
    char phys[32];          /* for input device */
    unsigned long pushed;
    bool wakeup_enabled;
};

static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
static struct acpi_device *lid_device;

/* --------------------------------------------------------------------------
                              FS Interface (/proc)
   -------------------------------------------------------------------------- */

static struct proc_dir_entry *acpi_button_dir;
static struct proc_dir_entry *acpi_lid_dir;

static int acpi_button_state_seq_show(struct seq_file *seq, void *offset)
{
    struct acpi_device *device = seq->private;
    acpi_status status;
    unsigned long long state;

    status = acpi_evaluate_integer(device->handle, "_LID", NULL, &state);
    seq_printf(seq, "state:      %s\n",
           ACPI_FAILURE(status) ? "unsupported" :
            (state ? "open" : "closed"));
    return 0;
}

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

static const struct file_operations acpi_button_state_fops = {
    .owner = THIS_MODULE,
    .open = acpi_button_state_open_fs,
    .read = seq_read,
    .llseek = seq_lseek,
    .release = single_release,
};

static int acpi_button_add_fs(struct acpi_device *device)
{
    struct acpi_button *button = acpi_driver_data(device);
    struct proc_dir_entry *entry = NULL;
    int ret = 0;

    /* procfs I/F for ACPI lid device only */
    if (button->type != ACPI_BUTTON_TYPE_LID)
        return 0;

    if (acpi_button_dir || acpi_lid_dir) {
        printk(KERN_ERR PREFIX "More than one Lid device found!\n");
        return -EEXIST;
    }

    /* create /proc/acpi/button */
    acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir);
    if (!acpi_button_dir)
        return -ENODEV;

    /* create /proc/acpi/button/lid */
    acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
    if (!acpi_lid_dir) {
        ret = -ENODEV;
        goto remove_button_dir;
    }

    /* create /proc/acpi/button/lid/LID/ */
    acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir);
    if (!acpi_device_dir(device)) {
        ret = -ENODEV;
        goto remove_lid_dir;
    }

    /* create /proc/acpi/button/lid/LID/state */
    entry = proc_create_data(ACPI_BUTTON_FILE_STATE,
                 S_IRUGO, acpi_device_dir(device),
                 &acpi_button_state_fops, device);
    if (!entry) {
        ret = -ENODEV;
        goto remove_dev_dir;
    }

done:
    return ret;

remove_dev_dir:
    remove_proc_entry(acpi_device_bid(device),
              acpi_lid_dir);
    acpi_device_dir(device) = NULL;
remove_lid_dir:
    remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
remove_button_dir:
    remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
    goto done;
}

static int acpi_button_remove_fs(struct acpi_device *device)
{
    struct acpi_button *button = acpi_driver_data(device);

    if (button->type != ACPI_BUTTON_TYPE_LID)
        return 0;

    remove_proc_entry(ACPI_BUTTON_FILE_STATE,
              acpi_device_dir(device));
    remove_proc_entry(acpi_device_bid(device),
              acpi_lid_dir);
    acpi_device_dir(device) = NULL;
    remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
    remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);

    return 0;
}

/* --------------------------------------------------------------------------
                                Driver Interface
   -------------------------------------------------------------------------- */
int acpi_lid_notifier_register(struct notifier_block *nb)
{
    return blocking_notifier_chain_register(&acpi_lid_notifier, nb);
}
EXPORT_SYMBOL(acpi_lid_notifier_register);

int acpi_lid_notifier_unregister(struct notifier_block *nb)
{
    return blocking_notifier_chain_unregister(&acpi_lid_notifier, nb);
}
EXPORT_SYMBOL(acpi_lid_notifier_unregister);

int acpi_lid_open(void)
{
    acpi_status status;
    unsigned long long state;

    if (!lid_device)
        return -ENODEV;

    status = acpi_evaluate_integer(lid_device->handle, "_LID", NULL,
                       &state);
    if (ACPI_FAILURE(status))
        return -ENODEV;

    return !!state;
}
EXPORT_SYMBOL(acpi_lid_open);

static int acpi_lid_send_state(struct acpi_device *device)
{
    struct acpi_button *button = acpi_driver_data(device);
    unsigned long long state;
    acpi_status status;
    int ret;

    status = acpi_evaluate_integer(device->handle, "_LID", NULL, &state);
    if (ACPI_FAILURE(status))
        return -ENODEV;

    /* input layer checks if event is redundant */
    input_report_switch(button->input, SW_LID, !state);
    input_sync(button->input);

    if (state)
        pm_wakeup_event(&device->dev, 0);

    ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, device);
    if (ret == NOTIFY_DONE)
        ret = blocking_notifier_call_chain(&acpi_lid_notifier, state,
                           device);
    if (ret == NOTIFY_DONE || ret == NOTIFY_OK) {
        /*
         * It is also regarded as success if the notifier_chain
         * returns NOTIFY_OK or NOTIFY_DONE.
         */
        ret = 0;
    }
    return ret;
}

static void acpi_button_notify(struct acpi_device *device, u32 event)
{
    struct acpi_button *button = acpi_driver_data(device);
    struct input_dev *input;

    switch (event) {
    case ACPI_FIXED_HARDWARE_EVENT:
        event = ACPI_BUTTON_NOTIFY_STATUS;
        /* fall through */
    case ACPI_BUTTON_NOTIFY_STATUS:
        input = button->input;
        if (button->type == ACPI_BUTTON_TYPE_LID) {
            acpi_lid_send_state(device);
        } else {
            int keycode = test_bit(KEY_SLEEP, input->keybit) ?
                        KEY_SLEEP : KEY_POWER;

            input_report_key(input, keycode, 1);
            input_sync(input);
            input_report_key(input, keycode, 0);
            input_sync(input);

            pm_wakeup_event(&device->dev, 0);
        }

        acpi_bus_generate_proc_event(device, event, ++button->pushed);
        break;
    default:
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                  "Unsupported event [0x%x]\n", event));
        break;
    }
}

#ifdef CONFIG_PM_SLEEP
static int acpi_button_resume(struct device *dev)
{
    struct acpi_device *device = to_acpi_device(dev);
    struct acpi_button *button = acpi_driver_data(device);

    if (button->type == ACPI_BUTTON_TYPE_LID)
        return acpi_lid_send_state(device);
    return 0;
}
#endif

static int acpi_button_add(struct acpi_device *device)
{
    struct acpi_button *button;
    struct input_dev *input;
    const char *hid = acpi_device_hid(device);
    char *name, *class;
    int error;

    button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
    if (!button)
        return -ENOMEM;

    device->driver_data = button;

    button->input = input = input_allocate_device();
    if (!input) {
        error = -ENOMEM;
        goto err_free_button;
    }

    name = acpi_device_name(device);
    class = acpi_device_class(device);

    if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
        !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
        button->type = ACPI_BUTTON_TYPE_POWER;
        strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
        sprintf(class, "%s/%s",
            ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
    } else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
           !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
        button->type = ACPI_BUTTON_TYPE_SLEEP;
        strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
        sprintf(class, "%s/%s",
            ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
    } else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
        button->type = ACPI_BUTTON_TYPE_LID;
        strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
        sprintf(class, "%s/%s",
            ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
    } else {
        printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid);
        error = -ENODEV;
        goto err_free_input;
    }

    error = acpi_button_add_fs(device);
    if (error)
        goto err_free_input;

    snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);

    input->name = name;
    input->phys = button->phys;
    input->id.bustype = BUS_HOST;
    input->id.product = button->type;
    input->dev.parent = &device->dev;

    switch (button->type) {
    case ACPI_BUTTON_TYPE_POWER:
        input->evbit[0] = BIT_MASK(EV_KEY);
        set_bit(KEY_POWER, input->keybit);
        break;

    case ACPI_BUTTON_TYPE_SLEEP:
        input->evbit[0] = BIT_MASK(EV_KEY);
        set_bit(KEY_SLEEP, input->keybit);
        break;

    case ACPI_BUTTON_TYPE_LID:
        input->evbit[0] = BIT_MASK(EV_SW);
        set_bit(SW_LID, input->swbit);
        break;
    }

    error = input_register_device(input);
    if (error)
        goto err_remove_fs;
    if (button->type == ACPI_BUTTON_TYPE_LID) {
        acpi_lid_send_state(device);
        /*
         * This assumes there's only one lid device, or if there are
         * more we only care about the last one...
         */
        lid_device = device;
    }

    if (device->wakeup.flags.valid) {
        /* Button's GPE is run-wake GPE */
        acpi_enable_gpe(device->wakeup.gpe_device,
                device->wakeup.gpe_number);
        if (!device_may_wakeup(&device->dev)) {
            device_set_wakeup_enable(&device->dev, true);
            button->wakeup_enabled = true;
        }
    }

    printk(KERN_INFO PREFIX "%s [%s]\n", name, acpi_device_bid(device));
    return 0;

 err_remove_fs:
    acpi_button_remove_fs(device);
 err_free_input:
    input_free_device(input);
 err_free_button:
    kfree(button);
    return error;
}

static int acpi_button_remove(struct acpi_device *device, int type)
{
    struct acpi_button *button = acpi_driver_data(device);

    if (device->wakeup.flags.valid) {
        acpi_disable_gpe(device->wakeup.gpe_device,
                device->wakeup.gpe_number);
        if (button->wakeup_enabled)
            device_set_wakeup_enable(&device->dev, false);
    }

    acpi_button_remove_fs(device);
    input_unregister_device(button->input);
    kfree(button);
    return 0;
}

module_acpi_driver(acpi_button_driver);