// SPDX-License-Identifier: GPL-2.0
/*
* adv_swbutton.c - Software Button Interface Driver.
*
* (C) Copyright 2020 Advantech Corporation, Inc
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/input.h>
#include <linux/acpi.h>
#include <linux/platform_device.h>
#define ACPI_BUTTON_HID_SWBTN "AHC0310"
#define ACPI_BUTTON_NOTIFY_SWBTN_RELEASE 0x86
#define ACPI_BUTTON_NOTIFY_SWBTN_PRESSED 0x85
struct adv_swbutton {
struct input_dev *input;
char phys[32];
};
/*-------------------------------------------------------------------------
* Driver Interface
*--------------------------------------------------------------------------
*/
static void adv_swbutton_notify(acpi_handle handle, u32 event, void *context)
{
struct platform_device *device = context;
struct adv_swbutton *button = dev_get_drvdata(&device->dev);
switch (event) {
case ACPI_BUTTON_NOTIFY_SWBTN_RELEASE:
input_report_key(button->input, KEY_PROG1, 0);
input_sync(button->input);
break;
case ACPI_BUTTON_NOTIFY_SWBTN_PRESSED:
input_report_key(button->input, KEY_PROG1, 1);
input_sync(button->input);
break;
default:
dev_dbg(&device->dev, "Unsupported event [0x%x]\n", event);
}
}
static int adv_swbutton_probe(struct platform_device *device)
{
struct adv_swbutton *button;
struct input_dev *input;
acpi_handle handle = ACPI_HANDLE(&device->dev);
acpi_status status;
int error;
button = devm_kzalloc(&device->dev, sizeof(*button), GFP_KERNEL);
if (!button)
return -ENOMEM;
dev_set_drvdata(&device->dev, button);
input = devm_input_allocate_device(&device->dev);
if (!input)
return -ENOMEM;
button->input = input;
snprintf(button->phys, sizeof(button->phys), "%s/button/input0", ACPI_BUTTON_HID_SWBTN);
input->name = "Advantech Software Button";
input->phys = button->phys;
input->id.bustype = BUS_HOST;
input->dev.parent = &device->dev;
set_bit(EV_REP, input->evbit);
input_set_capability(input, EV_KEY, KEY_PROG1);
error = input_register_device(input);
if (error)
return error;
device_init_wakeup(&device->dev, true);
status = acpi_install_notify_handler(handle,
ACPI_DEVICE_NOTIFY,
adv_swbutton_notify,
device);
if (ACPI_FAILURE(status)) {
dev_err(&device->dev, "Error installing notify handler\n");
return -EIO;
}
return 0;
}
static int adv_swbutton_remove(struct platform_device *device)
{
acpi_handle handle = ACPI_HANDLE(&device->dev);
acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY,
adv_swbutton_notify);
return 0;
}
static const struct acpi_device_id button_device_ids[] = {
{ACPI_BUTTON_HID_SWBTN, 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, button_device_ids);
static struct platform_driver adv_swbutton_driver = {
.driver = {
.name = "adv_swbutton",
.acpi_match_table = button_device_ids,
},
.probe = adv_swbutton_probe,
.remove = adv_swbutton_remove,
};
module_platform_driver(adv_swbutton_driver);
MODULE_AUTHOR("Andrea Ho");
MODULE_DESCRIPTION("Advantech ACPI SW Button Driver");
MODULE_LICENSE("GPL v2");