GNU Linux-libre 4.9.328-gnu1
[releases.git] / drivers / platform / x86 / intel-hid.c
1 /*
2  *  Intel HID event driver for Windows 8
3  *
4  *  Copyright (C) 2015 Alex Hung <alex.hung@canonical.com>
5  *  Copyright (C) 2015 Andrew Lutomirski <luto@kernel.org>
6  *
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.
11  *
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.
16  *
17  */
18
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>
27
28 MODULE_LICENSE("GPL");
29 MODULE_AUTHOR("Alex Hung");
30
31 static const struct acpi_device_id intel_hid_ids[] = {
32         {"INT33D5", 0},
33         {"", 0},
34 };
35
36 /* In theory, these are HID usages. */
37 static const struct key_entry intel_hid_keymap[] = {
38         /* 1: LSuper (Page 0x07, usage 0xE3) -- unclear what to do */
39         /* 2: Toggle SW_ROTATE_LOCK -- easy to implement if seen in wild */
40         { KE_KEY, 3, { KEY_NUMLOCK } },
41         { KE_KEY, 4, { KEY_HOME } },
42         { KE_KEY, 5, { KEY_END } },
43         { KE_KEY, 6, { KEY_PAGEUP } },
44         { KE_KEY, 7, { KEY_PAGEDOWN } },
45         { KE_KEY, 8, { KEY_RFKILL } },
46         { KE_KEY, 9, { KEY_POWER } },
47         { KE_KEY, 11, { KEY_SLEEP } },
48         /* 13 has two different meanings in the spec -- ignore it. */
49         { KE_KEY, 14, { KEY_STOPCD } },
50         { KE_KEY, 15, { KEY_PLAYPAUSE } },
51         { KE_KEY, 16, { KEY_MUTE } },
52         { KE_KEY, 17, { KEY_VOLUMEUP } },
53         { KE_KEY, 18, { KEY_VOLUMEDOWN } },
54         { KE_KEY, 19, { KEY_BRIGHTNESSUP } },
55         { KE_KEY, 20, { KEY_BRIGHTNESSDOWN } },
56         /* 27: wake -- needs special handling */
57         { KE_END },
58 };
59
60 struct intel_hid_priv {
61         struct input_dev *input_dev;
62 };
63
64 static int intel_hid_set_enable(struct device *device, int enable)
65 {
66         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
67         struct acpi_object_list args = { 1, &arg0 };
68         acpi_status status;
69
70         arg0.integer.value = enable;
71         status = acpi_evaluate_object(ACPI_HANDLE(device), "HDSM", &args, NULL);
72         if (!ACPI_SUCCESS(status)) {
73                 dev_warn(device, "failed to %sable hotkeys\n",
74                          enable ? "en" : "dis");
75                 return -EIO;
76         }
77
78         return 0;
79 }
80
81 static int intel_hid_pl_suspend_handler(struct device *device)
82 {
83         intel_hid_set_enable(device, 0);
84         return 0;
85 }
86
87 static int intel_hid_pl_resume_handler(struct device *device)
88 {
89         intel_hid_set_enable(device, 1);
90         return 0;
91 }
92
93 static const struct dev_pm_ops intel_hid_pl_pm_ops = {
94         .freeze  = intel_hid_pl_suspend_handler,
95         .restore  = intel_hid_pl_resume_handler,
96         .suspend  = intel_hid_pl_suspend_handler,
97         .resume  = intel_hid_pl_resume_handler,
98 };
99
100 static int intel_hid_input_setup(struct platform_device *device)
101 {
102         struct intel_hid_priv *priv = dev_get_drvdata(&device->dev);
103         int ret;
104
105         priv->input_dev = input_allocate_device();
106         if (!priv->input_dev)
107                 return -ENOMEM;
108
109         ret = sparse_keymap_setup(priv->input_dev, intel_hid_keymap, NULL);
110         if (ret)
111                 goto err_free_device;
112
113         priv->input_dev->dev.parent = &device->dev;
114         priv->input_dev->name = "Intel HID events";
115         priv->input_dev->id.bustype = BUS_HOST;
116         set_bit(KEY_RFKILL, priv->input_dev->keybit);
117
118         ret = input_register_device(priv->input_dev);
119         if (ret)
120                 goto err_free_device;
121
122         return 0;
123
124 err_free_device:
125         input_free_device(priv->input_dev);
126         return ret;
127 }
128
129 static void intel_hid_input_destroy(struct platform_device *device)
130 {
131         struct intel_hid_priv *priv = dev_get_drvdata(&device->dev);
132
133         input_unregister_device(priv->input_dev);
134 }
135
136 static void notify_handler(acpi_handle handle, u32 event, void *context)
137 {
138         struct platform_device *device = context;
139         struct intel_hid_priv *priv = dev_get_drvdata(&device->dev);
140         unsigned long long ev_index;
141         acpi_status status;
142
143         /* The platform spec only defines one event code: 0xC0. */
144         if (event != 0xc0) {
145                 dev_warn(&device->dev, "received unknown event (0x%x)\n",
146                          event);
147                 return;
148         }
149
150         status = acpi_evaluate_integer(handle, "HDEM", NULL, &ev_index);
151         if (!ACPI_SUCCESS(status)) {
152                 dev_warn(&device->dev, "failed to get event index\n");
153                 return;
154         }
155
156         if (!sparse_keymap_report_event(priv->input_dev, ev_index, 1, true))
157                 dev_info(&device->dev, "unknown event index 0x%llx\n",
158                          ev_index);
159 }
160
161 static int intel_hid_probe(struct platform_device *device)
162 {
163         acpi_handle handle = ACPI_HANDLE(&device->dev);
164         struct intel_hid_priv *priv;
165         unsigned long long mode;
166         acpi_status status;
167         int err;
168
169         status = acpi_evaluate_integer(handle, "HDMM", NULL, &mode);
170         if (!ACPI_SUCCESS(status)) {
171                 dev_warn(&device->dev, "failed to read mode\n");
172                 return -ENODEV;
173         }
174
175         if (mode != 0) {
176                 /*
177                  * This driver only implements "simple" mode.  There appear
178                  * to be no other modes, but we should be paranoid and check
179                  * for compatibility.
180                  */
181                 dev_info(&device->dev, "platform is not in simple mode\n");
182                 return -ENODEV;
183         }
184
185         priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
186         if (!priv)
187                 return -ENOMEM;
188         dev_set_drvdata(&device->dev, priv);
189
190         err = intel_hid_input_setup(device);
191         if (err) {
192                 pr_err("Failed to setup Intel HID hotkeys\n");
193                 return err;
194         }
195
196         status = acpi_install_notify_handler(handle,
197                                              ACPI_DEVICE_NOTIFY,
198                                              notify_handler,
199                                              device);
200         if (ACPI_FAILURE(status)) {
201                 err = -EBUSY;
202                 goto err_remove_input;
203         }
204
205         err = intel_hid_set_enable(&device->dev, 1);
206         if (err)
207                 goto err_remove_notify;
208
209         return 0;
210
211 err_remove_notify:
212         acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
213
214 err_remove_input:
215         intel_hid_input_destroy(device);
216
217         return err;
218 }
219
220 static int intel_hid_remove(struct platform_device *device)
221 {
222         acpi_handle handle = ACPI_HANDLE(&device->dev);
223
224         acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
225         intel_hid_input_destroy(device);
226         intel_hid_set_enable(&device->dev, 0);
227
228         /*
229          * Even if we failed to shut off the event stream, we can still
230          * safely detach from the device.
231          */
232         return 0;
233 }
234
235 static struct platform_driver intel_hid_pl_driver = {
236         .driver = {
237                 .name = "intel-hid",
238                 .acpi_match_table = intel_hid_ids,
239                 .pm = &intel_hid_pl_pm_ops,
240         },
241         .probe = intel_hid_probe,
242         .remove = intel_hid_remove,
243 };
244 MODULE_DEVICE_TABLE(acpi, intel_hid_ids);
245
246 /*
247  * Unfortunately, some laptops provide a _HID="INT33D5" device with
248  * _CID="PNP0C02".  This causes the pnpacpi scan driver to claim the
249  * ACPI node, so no platform device will be created.  The pnpacpi
250  * driver rejects this device in subsequent processing, so no physical
251  * node is created at all.
252  *
253  * As a workaround until the ACPI core figures out how to handle
254  * this corner case, manually ask the ACPI platform device code to
255  * claim the ACPI node.
256  */
257 static acpi_status __init
258 check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
259 {
260         const struct acpi_device_id *ids = context;
261         struct acpi_device *dev;
262
263         if (acpi_bus_get_device(handle, &dev) != 0)
264                 return AE_OK;
265
266         if (acpi_match_device_ids(dev, ids) == 0)
267                 if (!IS_ERR_OR_NULL(acpi_create_platform_device(dev, NULL)))
268                         dev_info(&dev->dev,
269                                  "intel-hid: created platform device\n");
270
271         return AE_OK;
272 }
273
274 static int __init intel_hid_init(void)
275 {
276         acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
277                             ACPI_UINT32_MAX, check_acpi_dev, NULL,
278                             (void *)intel_hid_ids, NULL);
279
280         return platform_driver_register(&intel_hid_pl_driver);
281 }
282 module_init(intel_hid_init);
283
284 static void __exit intel_hid_exit(void)
285 {
286         platform_driver_unregister(&intel_hid_pl_driver);
287 }
288 module_exit(intel_hid_exit);