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/init.h>
29 #include <linux/input.h>
30 #include <linux/types.h>
31 #include <asm/uaccess.h>
32 #include <acpi/acpi_drivers.h>
33 
34 #define ACPI_ATLAS_NAME		"Atlas ACPI"
35 #define ACPI_ATLAS_CLASS	"Atlas"
36 
37 static unsigned short atlas_keymap[16];
38 static struct input_dev *input_dev;
39 
40 /* button handling code */
acpi_atlas_button_setup(acpi_handle region_handle,u32 function,void * handler_context,void ** return_context)41 static acpi_status acpi_atlas_button_setup(acpi_handle region_handle,
42 		    u32 function, void *handler_context, void **return_context)
43 {
44 	*return_context =
45 		(function != ACPI_REGION_DEACTIVATE) ? handler_context : NULL;
46 
47 	return AE_OK;
48 }
49 
acpi_atlas_button_handler(u32 function,acpi_physical_address address,u32 bit_width,u64 * value,void * handler_context,void * region_context)50 static acpi_status acpi_atlas_button_handler(u32 function,
51 		      acpi_physical_address address,
52 		      u32 bit_width, u64 *value,
53 		      void *handler_context, void *region_context)
54 {
55 	acpi_status status;
56 
57 	if (function == ACPI_WRITE) {
58 		int code = address & 0x0f;
59 		int key_down = !(address & 0x10);
60 
61 		input_event(input_dev, EV_MSC, MSC_SCAN, code);
62 		input_report_key(input_dev, atlas_keymap[code], key_down);
63 		input_sync(input_dev);
64 
65 		status = AE_OK;
66 	} else {
67 		pr_warn("shrugged on unexpected function: function=%x,address=%lx,value=%x\n",
68 			function, (unsigned long)address, (u32)*value);
69 		status = AE_BAD_PARAMETER;
70 	}
71 
72 	return status;
73 }
74 
atlas_acpi_button_add(struct acpi_device * device)75 static int atlas_acpi_button_add(struct acpi_device *device)
76 {
77 	acpi_status status;
78 	int i;
79 	int err;
80 
81 	input_dev = input_allocate_device();
82 	if (!input_dev) {
83 		pr_err("unable to allocate input device\n");
84 		return -ENOMEM;
85 	}
86 
87 	input_dev->name = "Atlas ACPI button driver";
88 	input_dev->phys = "ASIM0000/atlas/input0";
89 	input_dev->id.bustype = BUS_HOST;
90 	input_dev->keycode = atlas_keymap;
91 	input_dev->keycodesize = sizeof(unsigned short);
92 	input_dev->keycodemax = ARRAY_SIZE(atlas_keymap);
93 
94 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
95 	__set_bit(EV_KEY, input_dev->evbit);
96 	for (i = 0; i < ARRAY_SIZE(atlas_keymap); i++) {
97 		if (i < 9) {
98 			atlas_keymap[i] = KEY_F1 + i;
99 			__set_bit(KEY_F1 + i, input_dev->keybit);
100 		} else
101 			atlas_keymap[i] = KEY_RESERVED;
102 	}
103 
104 	err = input_register_device(input_dev);
105 	if (err) {
106 		pr_err("couldn't register input device\n");
107 		input_free_device(input_dev);
108 		return err;
109 	}
110 
111 	/* hookup button handler */
112 	status = acpi_install_address_space_handler(device->handle,
113 				0x81, &acpi_atlas_button_handler,
114 				&acpi_atlas_button_setup, device);
115 	if (ACPI_FAILURE(status)) {
116 		pr_err("error installing addr spc handler\n");
117 		input_unregister_device(input_dev);
118 		err = -EINVAL;
119 	}
120 
121 	return err;
122 }
123 
atlas_acpi_button_remove(struct acpi_device * device,int type)124 static int atlas_acpi_button_remove(struct acpi_device *device, int type)
125 {
126 	acpi_status status;
127 
128 	status = acpi_remove_address_space_handler(device->handle,
129 				0x81, &acpi_atlas_button_handler);
130 	if (ACPI_FAILURE(status))
131 		pr_err("error removing addr spc handler\n");
132 
133 	input_unregister_device(input_dev);
134 
135 	return 0;
136 }
137 
138 static const struct acpi_device_id atlas_device_ids[] = {
139 	{"ASIM0000", 0},
140 	{"", 0},
141 };
142 MODULE_DEVICE_TABLE(acpi, atlas_device_ids);
143 
144 static struct acpi_driver atlas_acpi_driver = {
145 	.name	= ACPI_ATLAS_NAME,
146 	.class	= ACPI_ATLAS_CLASS,
147 	.owner	= THIS_MODULE,
148 	.ids	= atlas_device_ids,
149 	.ops	= {
150 		.add	= atlas_acpi_button_add,
151 		.remove	= atlas_acpi_button_remove,
152 	},
153 };
154 
atlas_acpi_init(void)155 static int __init atlas_acpi_init(void)
156 {
157 	if (acpi_disabled)
158 		return -ENODEV;
159 
160 	return acpi_bus_register_driver(&atlas_acpi_driver);
161 }
162 
atlas_acpi_exit(void)163 static void __exit atlas_acpi_exit(void)
164 {
165 	acpi_bus_unregister_driver(&atlas_acpi_driver);
166 }
167 
168 module_init(atlas_acpi_init);
169 module_exit(atlas_acpi_exit);
170 
171 MODULE_AUTHOR("Jaya Kumar");
172 MODULE_LICENSE("GPL");
173 MODULE_DESCRIPTION("Atlas button driver");
174 
175