1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Intel Virtual Button driver for Windows 8.1+
4 *
5 * Copyright (C) 2016 AceLan Kao <acelan.kao@canonical.com>
6 * Copyright (C) 2016 Alex Hung <alex.hung@canonical.com>
7 */
8
9 #include <linux/acpi.h>
10 #include <linux/dmi.h>
11 #include <linux/input.h>
12 #include <linux/input/sparse-keymap.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/suspend.h>
17
18 /* Returned when NOT in tablet mode on some HP Stream x360 11 models */
19 #define VGBS_TABLET_MODE_FLAG_ALT 0x10
20 /* When NOT in tablet mode, VGBS returns with the flag 0x40 */
21 #define VGBS_TABLET_MODE_FLAG 0x40
22 #define VGBS_DOCK_MODE_FLAG 0x80
23
24 #define VGBS_TABLET_MODE_FLAGS (VGBS_TABLET_MODE_FLAG | VGBS_TABLET_MODE_FLAG_ALT)
25
26 MODULE_LICENSE("GPL");
27 MODULE_AUTHOR("AceLan Kao");
28
29 static const struct acpi_device_id intel_vbtn_ids[] = {
30 {"INT33D6", 0},
31 {"", 0},
32 };
33 MODULE_DEVICE_TABLE(acpi, intel_vbtn_ids);
34
35 /* In theory, these are HID usages. */
36 static const struct key_entry intel_vbtn_keymap[] = {
37 { KE_KEY, 0xC0, { KEY_POWER } }, /* power key press */
38 { KE_IGNORE, 0xC1, { KEY_POWER } }, /* power key release */
39 { KE_KEY, 0xC2, { KEY_LEFTMETA } }, /* 'Windows' key press */
40 { KE_KEY, 0xC3, { KEY_LEFTMETA } }, /* 'Windows' key release */
41 { KE_KEY, 0xC4, { KEY_VOLUMEUP } }, /* volume-up key press */
42 { KE_IGNORE, 0xC5, { KEY_VOLUMEUP } }, /* volume-up key release */
43 { KE_KEY, 0xC6, { KEY_VOLUMEDOWN } }, /* volume-down key press */
44 { KE_IGNORE, 0xC7, { KEY_VOLUMEDOWN } }, /* volume-down key release */
45 { KE_KEY, 0xC8, { KEY_ROTATE_LOCK_TOGGLE } }, /* rotate-lock key press */
46 { KE_KEY, 0xC9, { KEY_ROTATE_LOCK_TOGGLE } }, /* rotate-lock key release */
47 };
48
49 static const struct key_entry intel_vbtn_switchmap[] = {
50 /*
51 * SW_DOCK should only be reported for docking stations, but DSDTs using the
52 * intel-vbtn code, always seem to use this for 2-in-1s / convertibles and set
53 * SW_DOCK=1 when in laptop-mode (in tandem with setting SW_TABLET_MODE=0).
54 * This causes userspace to think the laptop is docked to a port-replicator
55 * and to disable suspend-on-lid-close, which is undesirable.
56 * Map the dock events to KEY_IGNORE to avoid this broken SW_DOCK reporting.
57 */
58 { KE_IGNORE, 0xCA, { .sw = { SW_DOCK, 1 } } }, /* Docked */
59 { KE_IGNORE, 0xCB, { .sw = { SW_DOCK, 0 } } }, /* Undocked */
60 { KE_SW, 0xCC, { .sw = { SW_TABLET_MODE, 1 } } }, /* Tablet */
61 { KE_SW, 0xCD, { .sw = { SW_TABLET_MODE, 0 } } }, /* Laptop */
62 };
63
64 #define KEYMAP_LEN \
65 (ARRAY_SIZE(intel_vbtn_keymap) + ARRAY_SIZE(intel_vbtn_switchmap) + 1)
66
67 struct intel_vbtn_priv {
68 struct key_entry keymap[KEYMAP_LEN];
69 struct input_dev *input_dev;
70 bool has_buttons;
71 bool has_switches;
72 bool wakeup_mode;
73 };
74
detect_tablet_mode(struct platform_device * device)75 static void detect_tablet_mode(struct platform_device *device)
76 {
77 struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
78 acpi_handle handle = ACPI_HANDLE(&device->dev);
79 unsigned long long vgbs;
80 acpi_status status;
81 int m;
82
83 status = acpi_evaluate_integer(handle, "VGBS", NULL, &vgbs);
84 if (ACPI_FAILURE(status))
85 return;
86
87 m = !(vgbs & VGBS_TABLET_MODE_FLAGS);
88 input_report_switch(priv->input_dev, SW_TABLET_MODE, m);
89 m = (vgbs & VGBS_DOCK_MODE_FLAG) ? 1 : 0;
90 input_report_switch(priv->input_dev, SW_DOCK, m);
91 }
92
intel_vbtn_input_setup(struct platform_device * device)93 static int intel_vbtn_input_setup(struct platform_device *device)
94 {
95 struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
96 int ret, keymap_len = 0;
97
98 if (priv->has_buttons) {
99 memcpy(&priv->keymap[keymap_len], intel_vbtn_keymap,
100 ARRAY_SIZE(intel_vbtn_keymap) *
101 sizeof(struct key_entry));
102 keymap_len += ARRAY_SIZE(intel_vbtn_keymap);
103 }
104
105 if (priv->has_switches) {
106 memcpy(&priv->keymap[keymap_len], intel_vbtn_switchmap,
107 ARRAY_SIZE(intel_vbtn_switchmap) *
108 sizeof(struct key_entry));
109 keymap_len += ARRAY_SIZE(intel_vbtn_switchmap);
110 }
111
112 priv->keymap[keymap_len].type = KE_END;
113
114 priv->input_dev = devm_input_allocate_device(&device->dev);
115 if (!priv->input_dev)
116 return -ENOMEM;
117
118 ret = sparse_keymap_setup(priv->input_dev, priv->keymap, NULL);
119 if (ret)
120 return ret;
121
122 priv->input_dev->dev.parent = &device->dev;
123 priv->input_dev->name = "Intel Virtual Button driver";
124 priv->input_dev->id.bustype = BUS_HOST;
125
126 if (priv->has_switches)
127 detect_tablet_mode(device);
128
129 return input_register_device(priv->input_dev);
130 }
131
notify_handler(acpi_handle handle,u32 event,void * context)132 static void notify_handler(acpi_handle handle, u32 event, void *context)
133 {
134 struct platform_device *device = context;
135 struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
136 unsigned int val = !(event & 1); /* Even=press, Odd=release */
137 const struct key_entry *ke, *ke_rel;
138 bool autorelease;
139
140 if (priv->wakeup_mode) {
141 ke = sparse_keymap_entry_from_scancode(priv->input_dev, event);
142 if (ke) {
143 pm_wakeup_hard_event(&device->dev);
144
145 /*
146 * Switch events like tablet mode will wake the device
147 * and report the new switch position to the input
148 * subsystem.
149 */
150 if (ke->type == KE_SW)
151 sparse_keymap_report_event(priv->input_dev,
152 event,
153 val,
154 0);
155 return;
156 }
157 goto out_unknown;
158 }
159
160 /*
161 * Even press events are autorelease if there is no corresponding odd
162 * release event, or if the odd event is KE_IGNORE.
163 */
164 ke_rel = sparse_keymap_entry_from_scancode(priv->input_dev, event | 1);
165 autorelease = val && (!ke_rel || ke_rel->type == KE_IGNORE);
166
167 if (sparse_keymap_report_event(priv->input_dev, event, val, autorelease))
168 return;
169
170 out_unknown:
171 dev_dbg(&device->dev, "unknown event index 0x%x\n", event);
172 }
173
intel_vbtn_has_buttons(acpi_handle handle)174 static bool intel_vbtn_has_buttons(acpi_handle handle)
175 {
176 acpi_status status;
177
178 status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
179 return ACPI_SUCCESS(status);
180 }
181
182 /*
183 * There are several laptops (non 2-in-1) models out there which support VGBS,
184 * but simply always return 0, which we translate to SW_TABLET_MODE=1. This in
185 * turn causes userspace (libinput) to suppress events from the builtin
186 * keyboard and touchpad, making the laptop essentially unusable.
187 *
188 * Since the problem of wrongly reporting SW_TABLET_MODE=1 in combination
189 * with libinput, leads to a non-usable system. Where as OTOH many people will
190 * not even notice when SW_TABLET_MODE is not being reported, a DMI based allow
191 * list is used here. This list mainly matches on the chassis-type of 2-in-1s.
192 *
193 * There are also some 2-in-1s which use the intel-vbtn ACPI interface to report
194 * SW_TABLET_MODE with a chassis-type of 8 ("Portable") or 10 ("Notebook"),
195 * these are matched on a per model basis, since many normal laptops with a
196 * possible broken VGBS ACPI-method also use these chassis-types.
197 */
198 static const struct dmi_system_id dmi_switches_allow_list[] = {
199 {
200 .matches = {
201 DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "31" /* Convertible */),
202 },
203 },
204 {
205 .matches = {
206 DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "32" /* Detachable */),
207 },
208 },
209 {
210 .matches = {
211 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
212 DMI_MATCH(DMI_PRODUCT_NAME, "Venue 11 Pro 7130"),
213 },
214 },
215 {
216 .matches = {
217 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
218 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion 13 x360 PC"),
219 },
220 },
221 {
222 .matches = {
223 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
224 DMI_MATCH(DMI_PRODUCT_NAME, "Switch SA5-271"),
225 },
226 },
227 {
228 .matches = {
229 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
230 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7352"),
231 },
232 },
233 {} /* Array terminator */
234 };
235
intel_vbtn_has_switches(acpi_handle handle)236 static bool intel_vbtn_has_switches(acpi_handle handle)
237 {
238 unsigned long long vgbs;
239 acpi_status status;
240
241 if (!dmi_check_system(dmi_switches_allow_list))
242 return false;
243
244 status = acpi_evaluate_integer(handle, "VGBS", NULL, &vgbs);
245 return ACPI_SUCCESS(status);
246 }
247
intel_vbtn_probe(struct platform_device * device)248 static int intel_vbtn_probe(struct platform_device *device)
249 {
250 acpi_handle handle = ACPI_HANDLE(&device->dev);
251 bool has_buttons, has_switches;
252 struct intel_vbtn_priv *priv;
253 acpi_status status;
254 int err;
255
256 has_buttons = intel_vbtn_has_buttons(handle);
257 has_switches = intel_vbtn_has_switches(handle);
258
259 if (!has_buttons && !has_switches) {
260 dev_warn(&device->dev, "failed to read Intel Virtual Button driver\n");
261 return -ENODEV;
262 }
263
264 priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
265 if (!priv)
266 return -ENOMEM;
267 dev_set_drvdata(&device->dev, priv);
268
269 priv->has_buttons = has_buttons;
270 priv->has_switches = has_switches;
271
272 err = intel_vbtn_input_setup(device);
273 if (err) {
274 pr_err("Failed to setup Intel Virtual Button\n");
275 return err;
276 }
277
278 status = acpi_install_notify_handler(handle,
279 ACPI_DEVICE_NOTIFY,
280 notify_handler,
281 device);
282 if (ACPI_FAILURE(status))
283 return -EBUSY;
284
285 device_init_wakeup(&device->dev, true);
286 /*
287 * In order for system wakeup to work, the EC GPE has to be marked as
288 * a wakeup one, so do that here (this setting will persist, but it has
289 * no effect until the wakeup mask is set for the EC GPE).
290 */
291 acpi_ec_mark_gpe_for_wake();
292 return 0;
293 }
294
intel_vbtn_remove(struct platform_device * device)295 static int intel_vbtn_remove(struct platform_device *device)
296 {
297 acpi_handle handle = ACPI_HANDLE(&device->dev);
298
299 device_init_wakeup(&device->dev, false);
300 acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
301
302 /*
303 * Even if we failed to shut off the event stream, we can still
304 * safely detach from the device.
305 */
306 return 0;
307 }
308
intel_vbtn_pm_prepare(struct device * dev)309 static int intel_vbtn_pm_prepare(struct device *dev)
310 {
311 if (device_may_wakeup(dev)) {
312 struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
313
314 priv->wakeup_mode = true;
315 }
316 return 0;
317 }
318
intel_vbtn_pm_complete(struct device * dev)319 static void intel_vbtn_pm_complete(struct device *dev)
320 {
321 struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
322
323 priv->wakeup_mode = false;
324 }
325
intel_vbtn_pm_resume(struct device * dev)326 static int intel_vbtn_pm_resume(struct device *dev)
327 {
328 intel_vbtn_pm_complete(dev);
329 return 0;
330 }
331
332 static const struct dev_pm_ops intel_vbtn_pm_ops = {
333 .prepare = intel_vbtn_pm_prepare,
334 .complete = intel_vbtn_pm_complete,
335 .resume = intel_vbtn_pm_resume,
336 .restore = intel_vbtn_pm_resume,
337 .thaw = intel_vbtn_pm_resume,
338 };
339
340 static struct platform_driver intel_vbtn_pl_driver = {
341 .driver = {
342 .name = "intel-vbtn",
343 .acpi_match_table = intel_vbtn_ids,
344 .pm = &intel_vbtn_pm_ops,
345 },
346 .probe = intel_vbtn_probe,
347 .remove = intel_vbtn_remove,
348 };
349
350 static acpi_status __init
check_acpi_dev(acpi_handle handle,u32 lvl,void * context,void ** rv)351 check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
352 {
353 const struct acpi_device_id *ids = context;
354 struct acpi_device *dev;
355
356 if (acpi_bus_get_device(handle, &dev) != 0)
357 return AE_OK;
358
359 if (acpi_match_device_ids(dev, ids) == 0)
360 if (!IS_ERR_OR_NULL(acpi_create_platform_device(dev, NULL)))
361 dev_info(&dev->dev,
362 "intel-vbtn: created platform device\n");
363
364 return AE_OK;
365 }
366
intel_vbtn_init(void)367 static int __init intel_vbtn_init(void)
368 {
369 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
370 ACPI_UINT32_MAX, check_acpi_dev, NULL,
371 (void *)intel_vbtn_ids, NULL);
372
373 return platform_driver_register(&intel_vbtn_pl_driver);
374 }
375 module_init(intel_vbtn_init);
376
intel_vbtn_exit(void)377 static void __exit intel_vbtn_exit(void)
378 {
379 platform_driver_unregister(&intel_vbtn_pl_driver);
380 }
381 module_exit(intel_vbtn_exit);
382