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
intel_hid_set_enable(struct device * device,int enable)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
intel_hid_pl_suspend_handler(struct device * device)81 static int intel_hid_pl_suspend_handler(struct device *device)
82 {
83 intel_hid_set_enable(device, 0);
84 return 0;
85 }
86
intel_hid_pl_resume_handler(struct device * device)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
intel_hid_input_setup(struct platform_device * device)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
intel_hid_input_destroy(struct platform_device * device)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
notify_handler(acpi_handle handle,u32 event,void * context)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
intel_hid_probe(struct platform_device * device)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
intel_hid_remove(struct platform_device * device)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
check_acpi_dev(acpi_handle handle,u32 lvl,void * context,void ** rv)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 (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
intel_hid_init(void)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
intel_hid_exit(void)284 static void __exit intel_hid_exit(void)
285 {
286 platform_driver_unregister(&intel_hid_pl_driver);
287 }
288 module_exit(intel_hid_exit);
289