intel-smartconnect.c revision 5c7f80f75512557dd0728ada77e8e8a8c7c8458b 
1/*
2 *  Copyright 2013 Matthew Garrett <mjg59@srcf.ucam.org>
3 *
4 *  This program is free software; you can redistribute it and/or modify
5 *  it under the terms of the GNU General Public License as published by
6 *  the Free Software Foundation; either version 2 of the License, or
7 *  (at your option) any later version.
8 *
9 *  This program is distributed in the hope that it will be useful,
10 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
11 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 *  GNU General Public License for more details.
13 *
14 *  You should have received a copy of the GNU General Public License along
15 *  with this program; if not, write to the Free Software Foundation, Inc.,
16 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19
20#include <linux/init.h>
21#include <linux/module.h>
22#include <acpi/acpi_drivers.h>
23
24MODULE_LICENSE("GPL");
25
26static int smartconnect_acpi_init(struct acpi_device *acpi)
27{
28	struct acpi_object_list input;
29	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
30	union acpi_object *result;
31	union acpi_object param;
32	acpi_status status;
33
34	status = acpi_evaluate_object(acpi->handle, "GAOS", NULL, &output);
35	if (!ACPI_SUCCESS(status))
36		return -EINVAL;
37
38	result = output.pointer;
39
40	if (result->type != ACPI_TYPE_INTEGER) {
41		kfree(result);
42		return -EINVAL;
43	}
44
45	if (result->integer.value & 0x1) {
46		param.type = ACPI_TYPE_INTEGER;
47		param.integer.value = 0;
48
49		input.count = 1;
50		input.pointer = &param;
51
52		dev_info(&acpi->dev, "Disabling Intel Smart Connect\n");
53		status = acpi_evaluate_object(acpi->handle, "SAOS", &input,
54					      NULL);
55	}
56
57	kfree(result);
58
59	return 0;
60}
61
62static const struct acpi_device_id smartconnect_ids[] = {
63	{"INT33A0", 0},
64	{"", 0}
65};
66
67static struct acpi_driver smartconnect_driver = {
68	.owner = THIS_MODULE,
69	.name = "intel_smart_connect",
70	.class = "intel_smart_connect",
71	.ids = smartconnect_ids,
72	.ops = {
73		.add = smartconnect_acpi_init,
74	},
75};
76
77static int smartconnect_init(void)
78{
79	return acpi_bus_register_driver(&smartconnect_driver);
80}
81
82static void smartconnect_exit(void)
83{
84	acpi_bus_unregister_driver(&smartconnect_driver);
85}
86
87module_init(smartconnect_init);
88module_exit(smartconnect_exit);
89
90MODULE_DEVICE_TABLE(acpi, smartconnect_ids);
91