/*
* OLPC XO-1.5 ebook switch driver
* (based on generic ACPI button driver)
*
* Copyright (C) 2009 Paul Fox <pgf@laptop.org>
* Copyright (C) 2010 One Laptop per Child
*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/input.h>
#include <linux/acpi.h>
#define MODULE_NAME "xo15-ebook"
#define XO15_EBOOK_CLASS MODULE_NAME
#define XO15_EBOOK_TYPE_UNKNOWN 0x00
#define XO15_EBOOK_NOTIFY_STATUS 0x80
#define XO15_EBOOK_SUBCLASS "ebook"
#define XO15_EBOOK_HID "XO15EBK"
#define XO15_EBOOK_DEVICE_NAME "EBook Switch"
ACPI_MODULE_NAME(MODULE_NAME);
MODULE_DESCRIPTION("OLPC XO-1.5 ebook switch driver");
MODULE_LICENSE("GPL");
static const struct acpi_device_id ebook_device_ids[] = {
{ XO15_EBOOK_HID, 0 },
{ "", 0 },
};
MODULE_DEVICE_TABLE(acpi, ebook_device_ids);
struct ebook_switch {
struct input_dev *input;
char phys[32]; /* for input device */
};
static int ebook_send_state(struct acpi_device *device)
{
struct ebook_switch *button = acpi_driver_data(device);
unsigned long long state;
acpi_status status;
status = acpi_evaluate_integer(device->handle, "EBK", NULL, &state);
if (ACPI_FAILURE(status))
return -EIO;
/* input layer checks if event is redundant */
input_report_switch(button->input, SW_TABLET_MODE, !state);
input_sync(button->input);
return 0;
}
static void ebook_switch_notify(struct acpi_device *device, u32 event)
{
switch (event) {
case ACPI_FIXED_HARDWARE_EVENT:
case XO15_EBOOK_NOTIFY_STATUS:
ebook_send_state(device);
break;
default:
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Unsupported event [0x%x]\n", event));
break;
}
}
#ifdef CONFIG_PM_SLEEP
static int ebook_switch_resume(struct device *dev)
{
return ebook_send_state(to_acpi_device(dev));
}
#endif
static SIMPLE_DEV_PM_OPS(ebook_switch_pm, NULL, ebook_switch_resume);
static int ebook_switch_add(struct acpi_device *device)
{
struct ebook_switch *button;
struct input_dev *input;
const char *hid = acpi_device_hid(device);
char *name, *class;
int error;
button = kzalloc(sizeof(struct ebook_switch), 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, XO15_EBOOK_HID)) {
pr_err("Unsupported hid [%s]\n", hid);
error = -ENODEV;
goto err_free_input;
}
strcpy(name, XO15_EBOOK_DEVICE_NAME);
sprintf(class, "%s/%s", XO15_EBOOK_CLASS, XO15_EBOOK_SUBCLASS);
snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
input->name = name;
input->phys = button->phys;
input->id.bustype = BUS_HOST;
input->dev.parent = &device->dev;
input->evbit[0] = BIT_MASK(EV_SW);
set_bit(SW_TABLET_MODE, input->swbit);
error = input_register_device(input);
if (error)
goto err_free_input;
ebook_send_state(device);
if (device->wakeup.flags.valid) {
/* Button's GPE is run-wake GPE */
acpi_enable_gpe(device->wakeup.gpe_device,
device->wakeup.gpe_number);
device_set_wakeup_enable(&device->dev, true);
}
return 0;
err_free_input:
input_free_device(input);
err_free_button:
kfree(button);
return error;
}
static int ebook_switch_remove(struct acpi_device *device)
{
struct ebook_switch *button = acpi_driver_data(device);
input_unregister_device(button->input);
kfree(button);
return 0;
}
static struct acpi_driver xo15_ebook_driver = {
.name = MODULE_NAME,
.class = XO15_EBOOK_CLASS,
.ids = ebook_device_ids,
.ops = {
.add = ebook_switch_add,
.remove = ebook_switch_remove,
.notify = ebook_switch_notify,
},
.drv.pm = &ebook_switch_pm,
};
module_acpi_driver(xo15_ebook_driver);
