xref: /linux/drivers/input/misc/atlas_btns.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 
36 static unsigned short atlas_keymap[16];
37 static struct input_dev *input_dev;
38 
39 /* button handling code */
40 static 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 
49 static 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 
74 static 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 
123 static 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 
137 static const struct acpi_device_id atlas_device_ids[] = {
138 	{"ASIM0000", 0},
139 	{"", 0},
140 };
141 MODULE_DEVICE_TABLE(acpi, atlas_device_ids);
142 
143 static 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 };
153 module_acpi_driver(atlas_acpi_driver);
154 
155 MODULE_AUTHOR("Jaya Kumar");
156 MODULE_LICENSE("GPL");
157 MODULE_DESCRIPTION("Atlas button driver");
158 
159