aboutsummaryrefslogtreecommitdiff
path: root/drivers/platform/x86/xo15-ebook.c
blob: 849c07c13bf6cae790c3e99dfb402f55b88a2a1f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
/*
 *  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 <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.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;
	}
}

static int ebook_switch_resume(struct device *dev)
{
	return ebook_send_state(to_acpi_device(dev));
}

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, int type)
{
	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,
};

static int __init xo15_ebook_init(void)
{
	return acpi_bus_register_driver(&xo15_ebook_driver);
}

static void __exit xo15_ebook_exit(void)
{
	acpi_bus_unregister_driver(&xo15_ebook_driver);
}

module_init(xo15_ebook_init);
module_exit(xo15_ebook_exit);