2 * Intel Virtual Button driver for Windows 8.1+
4 * Copyright (C) 2016 AceLan Kao <acelan.kao@canonical.com>
5 * Copyright (C) 2016 Alex Hung <alex.hung@canonical.com>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/input.h>
23 #include <linux/platform_device.h>
24 #include <linux/input/sparse-keymap.h>
25 #include <linux/acpi.h>
26 #include <acpi/acpi_bus.h>
28 MODULE_LICENSE("GPL");
29 MODULE_AUTHOR("AceLan Kao");
31 static const struct acpi_device_id intel_vbtn_ids
[] = {
36 /* In theory, these are HID usages. */
37 static const struct key_entry intel_vbtn_keymap
[] = {
38 { KE_IGNORE
, 0xC0, { KEY_POWER
} }, /* power key press */
39 { KE_KEY
, 0xC1, { KEY_POWER
} }, /* power key release */
43 struct intel_vbtn_priv
{
44 struct input_dev
*input_dev
;
47 static int intel_vbtn_input_setup(struct platform_device
*device
)
49 struct intel_vbtn_priv
*priv
= dev_get_drvdata(&device
->dev
);
52 priv
->input_dev
= devm_input_allocate_device(&device
->dev
);
56 ret
= sparse_keymap_setup(priv
->input_dev
, intel_vbtn_keymap
, NULL
);
60 priv
->input_dev
->dev
.parent
= &device
->dev
;
61 priv
->input_dev
->name
= "Intel Virtual Button driver";
62 priv
->input_dev
->id
.bustype
= BUS_HOST
;
64 return input_register_device(priv
->input_dev
);
67 static void notify_handler(acpi_handle handle
, u32 event
, void *context
)
69 struct platform_device
*device
= context
;
70 struct intel_vbtn_priv
*priv
= dev_get_drvdata(&device
->dev
);
72 if (!sparse_keymap_report_event(priv
->input_dev
, event
, 1, true))
73 dev_info(&device
->dev
, "unknown event index 0x%x\n",
77 static int intel_vbtn_probe(struct platform_device
*device
)
79 acpi_handle handle
= ACPI_HANDLE(&device
->dev
);
80 struct intel_vbtn_priv
*priv
;
84 status
= acpi_evaluate_object(handle
, "VBDL", NULL
, NULL
);
85 if (ACPI_FAILURE(status
)) {
86 dev_warn(&device
->dev
, "failed to read Intel Virtual Button driver\n");
90 priv
= devm_kzalloc(&device
->dev
, sizeof(*priv
), GFP_KERNEL
);
93 dev_set_drvdata(&device
->dev
, priv
);
95 err
= intel_vbtn_input_setup(device
);
97 pr_err("Failed to setup Intel Virtual Button\n");
101 status
= acpi_install_notify_handler(handle
,
105 if (ACPI_FAILURE(status
))
111 static int intel_vbtn_remove(struct platform_device
*device
)
113 acpi_handle handle
= ACPI_HANDLE(&device
->dev
);
115 acpi_remove_notify_handler(handle
, ACPI_DEVICE_NOTIFY
, notify_handler
);
118 * Even if we failed to shut off the event stream, we can still
119 * safely detach from the device.
124 static struct platform_driver intel_vbtn_pl_driver
= {
126 .name
= "intel-vbtn",
127 .acpi_match_table
= intel_vbtn_ids
,
129 .probe
= intel_vbtn_probe
,
130 .remove
= intel_vbtn_remove
,
132 MODULE_DEVICE_TABLE(acpi
, intel_vbtn_ids
);
134 static acpi_status __init
135 check_acpi_dev(acpi_handle handle
, u32 lvl
, void *context
, void **rv
)
137 const struct acpi_device_id
*ids
= context
;
138 struct acpi_device
*dev
;
140 if (acpi_bus_get_device(handle
, &dev
) != 0)
143 if (acpi_match_device_ids(dev
, ids
) == 0)
144 if (acpi_create_platform_device(dev
, NULL
))
146 "intel-vbtn: created platform device\n");
151 static int __init
intel_vbtn_init(void)
153 acpi_walk_namespace(ACPI_TYPE_DEVICE
, ACPI_ROOT_OBJECT
,
154 ACPI_UINT32_MAX
, check_acpi_dev
, NULL
,
155 (void *)intel_vbtn_ids
, NULL
);
157 return platform_driver_register(&intel_vbtn_pl_driver
);
159 module_init(intel_vbtn_init
);
161 static void __exit
intel_vbtn_exit(void)
163 platform_driver_unregister(&intel_vbtn_pl_driver
);
165 module_exit(intel_vbtn_exit
);