1/*
2 *  atlas_btns.c - Atlas Wallmount Touchscreen ACPI Extras
3 *
4 *  Copyright (C) 2006 Jaya Kumar
5 *  Based on Toshiba ACPI by John Belmonte and ASUS ACPI
6 *  This work was sponsored by CIS(M) Sdn Bhd.
7 *
8 *  This program is free software; you can redistribute it and/or modify
9 *  it under the terms of the GNU General Public License as published by
10 *  the Free Software Foundation; either version 2 of the License, or
11 *  (at your option) any later version.
12 *
13 *  This program is distributed in the hope that it will be useful,
14 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 *  GNU General Public License for more details.
17 *
18 *  You should have received a copy of the GNU General Public License
19 *  along with this program; if not, write to the Free Software
20 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21 *
22 */
23
24#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
25
26#include <linux/kernel.h>
27#include <linux/module.h>
28#include <linux/input.h>
29#include <linux/types.h>
30#include <linux/acpi.h>
31#include <asm/uaccess.h>
32
33#define ACPI_ATLAS_NAME		"Atlas ACPI"
34#define ACPI_ATLAS_CLASS	"Atlas"
35
36static unsigned short atlas_keymap[16];
37static struct input_dev *input_dev;
38
39/* button handling code */
40static acpi_status acpi_atlas_button_setup(acpi_handle region_handle,
41		    u32 function, void *handler_context, void **return_context)
42{
43	*return_context =
44		(function != ACPI_REGION_DEACTIVATE) ? handler_context : NULL;
45
46	return AE_OK;
47}
48
49static acpi_status acpi_atlas_button_handler(u32 function,
50		      acpi_physical_address address,
51		      u32 bit_width, u64 *value,
52		      void *handler_context, void *region_context)
53{
54	acpi_status status;
55
56	if (function == ACPI_WRITE) {
57		int code = address & 0x0f;
58		int key_down = !(address & 0x10);
59
60		input_event(input_dev, EV_MSC, MSC_SCAN, code);
61		input_report_key(input_dev, atlas_keymap[code], key_down);
62		input_sync(input_dev);
63
64		status = AE_OK;
65	} else {
66		pr_warn("shrugged on unexpected function: function=%x,address=%lx,value=%x\n",
67			function, (unsigned long)address, (u32)*value);
68		status = AE_BAD_PARAMETER;
69	}
70
71	return status;
72}
73
74static int atlas_acpi_button_add(struct acpi_device *device)
75{
76	acpi_status status;
77	int i;
78	int err;
79
80	input_dev = input_allocate_device();
81	if (!input_dev) {
82		pr_err("unable to allocate input device\n");
83		return -ENOMEM;
84	}
85
86	input_dev->name = "Atlas ACPI button driver";
87	input_dev->phys = "ASIM0000/atlas/input0";
88	input_dev->id.bustype = BUS_HOST;
89	input_dev->keycode = atlas_keymap;
90	input_dev->keycodesize = sizeof(unsigned short);
91	input_dev->keycodemax = ARRAY_SIZE(atlas_keymap);
92
93	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
94	__set_bit(EV_KEY, input_dev->evbit);
95	for (i = 0; i < ARRAY_SIZE(atlas_keymap); i++) {
96		if (i < 9) {
97			atlas_keymap[i] = KEY_F1 + i;
98			__set_bit(KEY_F1 + i, input_dev->keybit);
99		} else
100			atlas_keymap[i] = KEY_RESERVED;
101	}
102
103	err = input_register_device(input_dev);
104	if (err) {
105		pr_err("couldn't register input device\n");
106		input_free_device(input_dev);
107		return err;
108	}
109
110	/* hookup button handler */
111	status = acpi_install_address_space_handler(device->handle,
112				0x81, &acpi_atlas_button_handler,
113				&acpi_atlas_button_setup, device);
114	if (ACPI_FAILURE(status)) {
115		pr_err("error installing addr spc handler\n");
116		input_unregister_device(input_dev);
117		err = -EINVAL;
118	}
119
120	return err;
121}
122
123static int atlas_acpi_button_remove(struct acpi_device *device)
124{
125	acpi_status status;
126
127	status = acpi_remove_address_space_handler(device->handle,
128				0x81, &acpi_atlas_button_handler);
129	if (ACPI_FAILURE(status))
130		pr_err("error removing addr spc handler\n");
131
132	input_unregister_device(input_dev);
133
134	return 0;
135}
136
137static const struct acpi_device_id atlas_device_ids[] = {
138	{"ASIM0000", 0},
139	{"", 0},
140};
141MODULE_DEVICE_TABLE(acpi, atlas_device_ids);
142
143static struct acpi_driver atlas_acpi_driver = {
144	.name	= ACPI_ATLAS_NAME,
145	.class	= ACPI_ATLAS_CLASS,
146	.owner	= THIS_MODULE,
147	.ids	= atlas_device_ids,
148	.ops	= {
149		.add	= atlas_acpi_button_add,
150		.remove	= atlas_acpi_button_remove,
151	},
152};
153module_acpi_driver(atlas_acpi_driver);
154
155MODULE_AUTHOR("Jaya Kumar");
156MODULE_LICENSE("GPL");
157MODULE_DESCRIPTION("Atlas button driver");
158
159