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/*
* button.c - ACPI Button Driver
*
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* 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.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#define pr_fmt(fmt) "ACPI : button: " fmt
#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 <linux/acpi.h>
#include <acpi/button.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 ACPI_BUTTON_LID_INIT_IGNORE 0x00
#define ACPI_BUTTON_LID_INIT_OPEN 0x01
#define ACPI_BUTTON_LID_INIT_METHOD 0x02
#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);
static void acpi_button_notify(struct acpi_device *device, u32 event);
#ifdef CONFIG_PM_SLEEP
static int acpi_button_suspend(struct device *dev);
static int acpi_button_resume(struct device *dev);
#else
#define acpi_button_suspend NULL
#define acpi_button_resume NULL
#endif
static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, 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;
int last_state;
ktime_t last_time;
bool suspended;
};
static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
static struct acpi_device *lid_device;
static u8 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
static unsigned long lid_report_interval __read_mostly = 500;
module_param(lid_report_interval, ulong, 0644);
MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
/* --------------------------------------------------------------------------
FS Interface (/proc)
-------------------------------------------------------------------------- */
static struct proc_dir_entry *acpi_button_dir;
static struct proc_dir_entry *acpi_lid_dir;
static int acpi_lid_evaluate_state(struct acpi_device *device)
{
unsigned long long lid_state;
acpi_status status;
status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state);
if (ACPI_FAILURE(status))
return -ENODEV;
return lid_state ? 1 : 0;
}
static int acpi_lid_notify_state(struct acpi_device *device, int state)
{
struct acpi_button *button = acpi_driver_data(device);
int ret;
ktime_t next_report;
bool do_update;
/*
* In lid_init_state=ignore mode, if user opens/closes lid
* frequently with "open" missing, and "last_time" is also updated
* frequently, "close" cannot be delivered to the userspace.
* So "last_time" is only updated after a timeout or an actual
* switch.
*/
if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE ||
button->last_state != !!state)
do_update = true;
else
do_update = false;
next_report = ktime_add(button->last_time,
ms_to_ktime(lid_report_interval));
if (button->last_state == !!state &&
ktime_after(ktime_get(), next_report)) {
/* Complain the buggy firmware */
pr_warn_once("The lid device is not compliant to SW_LID.\n");
/*
* Send the unreliable complement switch event:
*
* On most platforms, the lid device is reliable. However
* there are exceptions:
* 1. Platforms returning initial lid state as "close" by
* default after booting/resuming:
* https://bugzilla.kernel.org/show_bug.cgi?id=89211
* https://bugzilla.kernel.org/show_bug.cgi?id=106151
* 2. Platforms never reporting "open" events:
* https://bugzilla.kernel.org/show_bug.cgi?id=106941
* On these buggy platforms, the usage model of the ACPI
* lid device actually is:
* 1. The initial returning value of _LID may not be
* reliable.
* 2. The open event may not be reliable.
* 3. The close event is reliable.
*
* But SW_LID is typed as input switch event, the input
* layer checks if the event is redundant. Hence if the
* state is not switched, the userspace cannot see this
* platform triggered reliable event. By inserting a
* complement switch event, it then is guaranteed that the
* platform triggered reliable one can always be seen by
* the userspace.
*/
if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) {
do_update = true;
/*
* Do generate complement switch event for "close"
* as "close" is reliable and wrong "open" won't
* trigger unexpected behaviors.
* Do not generate complement switch event for
* "open" as "open" is not reliable and wrong
* "close" will trigger unexpected behaviors.
*/
if (!state) {
input_report_switch(button->input,
SW_LID, state);
input_sync(button->input);
}
}
}
/* Send the platform triggered reliable event */
if (do_update) {
input_report_switch(button->input, SW_LID, !state);
input_sync(button->input);
button->last_state = !!state;
button->last_time = ktime_get();
}
if (state)
pm_wakeup_hard_event(&device->dev);
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 int acpi_button_state_seq_show(struct seq_file *seq, void *offset)
{
struct acpi_device *device = seq->private;
int state;
state = acpi_lid_evaluate_state(device);
seq_printf(seq, "state: %s\n",
state < 0 ? "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_DATA(inode));
}
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,
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