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/cleanup.h>
11 #include <linux/dmi.h>
12 #include <linux/input.h>
13 #include <linux/input/sparse-keymap.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/mutex.h>
17 #include <linux/platform_device.h>
18 #include <linux/suspend.h>
19 #include "../dual_accel_detect.h"
20
21 /* Returned when NOT in tablet mode on some HP Stream x360 11 models */
22 #define VGBS_TABLET_MODE_FLAG_ALT 0x10
23 /* When NOT in tablet mode, VGBS returns with the flag 0x40 */
24 #define VGBS_TABLET_MODE_FLAG 0x40
25 #define VGBS_DOCK_MODE_FLAG 0x80
26
27 #define VGBS_TABLET_MODE_FLAGS (VGBS_TABLET_MODE_FLAG | VGBS_TABLET_MODE_FLAG_ALT)
28
29 MODULE_DESCRIPTION("Intel Virtual Button driver");
30 MODULE_LICENSE("GPL");
31 MODULE_AUTHOR("AceLan Kao");
32
33 static const struct acpi_device_id intel_vbtn_ids[] = {
34 {"INT33D6", 0},
35 {"", 0},
36 };
37 MODULE_DEVICE_TABLE(acpi, intel_vbtn_ids);
38
39 /* In theory, these are HID usages. */
40 static const struct key_entry intel_vbtn_keymap[] = {
41 { KE_KEY, 0xC0, { KEY_POWER } }, /* power key press */
42 { KE_IGNORE, 0xC1, { KEY_POWER } }, /* power key release */
43 { KE_KEY, 0xC2, { KEY_LEFTMETA } }, /* 'Windows' key press */
44 { KE_KEY, 0xC3, { KEY_LEFTMETA } }, /* 'Windows' key release */
45 { KE_KEY, 0xC4, { KEY_VOLUMEUP } }, /* volume-up key press */
46 { KE_IGNORE, 0xC5, { KEY_VOLUMEUP } }, /* volume-up key release */
47 { KE_KEY, 0xC6, { KEY_VOLUMEDOWN } }, /* volume-down key press */
48 { KE_IGNORE, 0xC7, { KEY_VOLUMEDOWN } }, /* volume-down key release */
49 { KE_KEY, 0xC8, { KEY_ROTATE_LOCK_TOGGLE } }, /* rotate-lock key press */
50 { KE_KEY, 0xC9, { KEY_ROTATE_LOCK_TOGGLE } }, /* rotate-lock key release */
51 { KE_END }
52 };
53
54 static const struct key_entry intel_vbtn_switchmap[] = {
55 /*
56 * SW_DOCK should only be reported for docking stations, but DSDTs using the
57 * intel-vbtn code, always seem to use this for 2-in-1s / convertibles and set
58 * SW_DOCK=1 when in laptop-mode (in tandem with setting SW_TABLET_MODE=0).
59 * This causes userspace to think the laptop is docked to a port-replicator
60 * and to disable suspend-on-lid-close, which is undesirable.
61 * Map the dock events to KEY_IGNORE to avoid this broken SW_DOCK reporting.
62 */
63 { KE_IGNORE, 0xCA, { .sw = { SW_DOCK, 1 } } }, /* Docked */
64 { KE_IGNORE, 0xCB, { .sw = { SW_DOCK, 0 } } }, /* Undocked */
65 { KE_SW, 0xCC, { .sw = { SW_TABLET_MODE, 1 } } }, /* Tablet */
66 { KE_SW, 0xCD, { .sw = { SW_TABLET_MODE, 0 } } }, /* Laptop */
67 { KE_END }
68 };
69
70 struct intel_vbtn_priv {
71 struct mutex mutex; /* Avoid notify_handler() racing with itself */
72 struct input_dev *buttons_dev;
73 struct input_dev *switches_dev;
74 bool dual_accel;
75 bool has_buttons;
76 bool has_switches;
77 bool wakeup_mode;
78 };
79
detect_tablet_mode(struct device * dev)80 static void detect_tablet_mode(struct device *dev)
81 {
82 struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
83 acpi_handle handle = ACPI_HANDLE(dev);
84 unsigned long long vgbs;
85 acpi_status status;
86 int m;
87
88 status = acpi_evaluate_integer(handle, "VGBS", NULL, &vgbs);
89 if (ACPI_FAILURE(status))
90 return;
91
92 m = !(vgbs & VGBS_TABLET_MODE_FLAGS);
93 input_report_switch(priv->switches_dev, SW_TABLET_MODE, m);
94 m = (vgbs & VGBS_DOCK_MODE_FLAG) ? 1 : 0;
95 input_report_switch(priv->switches_dev, SW_DOCK, m);
96
97 input_sync(priv->switches_dev);
98 }
99
100 /*
101 * Note this unconditionally creates the 2 input_dev-s and sets up
102 * the sparse-keymaps. Only the registration is conditional on
103 * have_buttons / have_switches. This is done so that the notify
104 * handler can always call sparse_keymap_entry_from_scancode()
105 * on the input_dev-s do determine the event type.
106 */
intel_vbtn_input_setup(struct platform_device * device)107 static int intel_vbtn_input_setup(struct platform_device *device)
108 {
109 struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
110 int ret;
111
112 priv->buttons_dev = devm_input_allocate_device(&device->dev);
113 if (!priv->buttons_dev)
114 return -ENOMEM;
115
116 ret = sparse_keymap_setup(priv->buttons_dev, intel_vbtn_keymap, NULL);
117 if (ret)
118 return ret;
119
120 priv->buttons_dev->dev.parent = &device->dev;
121 priv->buttons_dev->name = "Intel Virtual Buttons";
122 priv->buttons_dev->id.bustype = BUS_HOST;
123
124 if (priv->has_buttons) {
125 ret = input_register_device(priv->buttons_dev);
126 if (ret)
127 return ret;
128 }
129
130 priv->switches_dev = devm_input_allocate_device(&device->dev);
131 if (!priv->switches_dev)
132 return -ENOMEM;
133
134 ret = sparse_keymap_setup(priv->switches_dev, intel_vbtn_switchmap, NULL);
135 if (ret)
136 return ret;
137
138 priv->switches_dev->dev.parent = &device->dev;
139 priv->switches_dev->name = "Intel Virtual Switches";
140 priv->switches_dev->id.bustype = BUS_HOST;
141
142 if (priv->has_switches) {
143 ret = input_register_device(priv->switches_dev);
144 if (ret)
145 return ret;
146 }
147
148 return 0;
149 }
150
notify_handler(acpi_handle handle,u32 event,void * context)151 static void notify_handler(acpi_handle handle, u32 event, void *context)
152 {
153 struct platform_device *device = context;
154 struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
155 unsigned int val = !(event & 1); /* Even=press, Odd=release */
156 const struct key_entry *ke, *ke_rel;
157 struct input_dev *input_dev;
158 bool autorelease;
159 int ret;
160
161 guard(mutex)(&priv->mutex);
162
163 if ((ke = sparse_keymap_entry_from_scancode(priv->buttons_dev, event))) {
164 if (!priv->has_buttons) {
165 dev_warn(&device->dev, "Warning: received 0x%02x button event on a device without buttons, please report this.\n",
166 event);
167 return;
168 }
169 input_dev = priv->buttons_dev;
170 } else if ((ke = sparse_keymap_entry_from_scancode(priv->switches_dev, event))) {
171 if (!priv->has_switches) {
172 /* See dual_accel_detect.h for more info */
173 if (priv->dual_accel)
174 return;
175
176 dev_info(&device->dev, "Registering Intel Virtual Switches input-dev after receiving a switch event\n");
177 ret = input_register_device(priv->switches_dev);
178 if (ret)
179 return;
180
181 priv->has_switches = true;
182 }
183 input_dev = priv->switches_dev;
184 } else {
185 dev_dbg(&device->dev, "unknown event index 0x%x\n", event);
186 return;
187 }
188
189 if (priv->wakeup_mode) {
190 pm_wakeup_hard_event(&device->dev);
191
192 /*
193 * Skip reporting an evdev event for button wake events,
194 * mirroring how the drivers/acpi/button.c code skips this too.
195 */
196 if (ke->type == KE_KEY)
197 return;
198 }
199
200 /*
201 * Even press events are autorelease if there is no corresponding odd
202 * release event, or if the odd event is KE_IGNORE.
203 */
204 ke_rel = sparse_keymap_entry_from_scancode(input_dev, event | 1);
205 autorelease = val && (!ke_rel || ke_rel->type == KE_IGNORE);
206
207 sparse_keymap_report_event(input_dev, event, val, autorelease);
208 }
209
210 /*
211 * There are several laptops (non 2-in-1) models out there which support VGBS,
212 * but simply always return 0, which we translate to SW_TABLET_MODE=1. This in
213 * turn causes userspace (libinput) to suppress events from the builtin
214 * keyboard and touchpad, making the laptop essentially unusable.
215 *
216 * Since the problem of wrongly reporting SW_TABLET_MODE=1 in combination
217 * with libinput, leads to a non-usable system. Where as OTOH many people will
218 * not even notice when SW_TABLET_MODE is not being reported, a DMI based allow
219 * list is used here. This list mainly matches on the chassis-type of 2-in-1s.
220 *
221 * There are also some 2-in-1s which use the intel-vbtn ACPI interface to report
222 * SW_TABLET_MODE with a chassis-type of 8 ("Portable") or 10 ("Notebook"),
223 * these are matched on a per model basis, since many normal laptops with a
224 * possible broken VGBS ACPI-method also use these chassis-types.
225 */
226 static const struct dmi_system_id dmi_switches_allow_list[] = {
227 {
228 .matches = {
229 DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "31" /* Convertible */),
230 },
231 },
232 {
233 .matches = {
234 DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "32" /* Detachable */),
235 },
236 },
237 {
238 .matches = {
239 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
240 DMI_MATCH(DMI_PRODUCT_NAME, "Venue 11 Pro 7130"),
241 },
242 },
243 {
244 .matches = {
245 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
246 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion 13 x360 PC"),
247 },
248 },
249 {
250 .matches = {
251 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
252 DMI_MATCH(DMI_PRODUCT_NAME, "Switch SA5-271"),
253 },
254 },
255 {
256 .matches = {
257 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
258 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7352"),
259 },
260 },
261 {} /* Array terminator */
262 };
263
intel_vbtn_has_switches(acpi_handle handle,bool dual_accel)264 static bool intel_vbtn_has_switches(acpi_handle handle, bool dual_accel)
265 {
266 /* See dual_accel_detect.h for more info */
267 if (dual_accel)
268 return false;
269
270 if (!dmi_check_system(dmi_switches_allow_list))
271 return false;
272
273 return acpi_has_method(handle, "VGBS");
274 }
275
intel_vbtn_probe(struct platform_device * device)276 static int intel_vbtn_probe(struct platform_device *device)
277 {
278 acpi_handle handle = ACPI_HANDLE(&device->dev);
279 bool dual_accel, has_buttons, has_switches;
280 struct intel_vbtn_priv *priv;
281 acpi_status status;
282 int err;
283
284 dual_accel = dual_accel_detect();
285 has_buttons = acpi_has_method(handle, "VBDL");
286 has_switches = intel_vbtn_has_switches(handle, dual_accel);
287
288 if (!has_buttons && !has_switches) {
289 dev_warn(&device->dev, "failed to read Intel Virtual Button driver\n");
290 return -ENODEV;
291 }
292
293 priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
294 if (!priv)
295 return -ENOMEM;
296 dev_set_drvdata(&device->dev, priv);
297
298 err = devm_mutex_init(&device->dev, &priv->mutex);
299 if (err)
300 return err;
301
302 priv->dual_accel = dual_accel;
303 priv->has_buttons = has_buttons;
304 priv->has_switches = has_switches;
305
306 err = intel_vbtn_input_setup(device);
307 if (err) {
308 pr_err("Failed to setup Intel Virtual Button\n");
309 return err;
310 }
311
312 status = acpi_install_notify_handler(handle,
313 ACPI_DEVICE_NOTIFY,
314 notify_handler,
315 device);
316 if (ACPI_FAILURE(status))
317 return -EBUSY;
318
319 if (has_buttons) {
320 status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
321 if (ACPI_FAILURE(status))
322 dev_err(&device->dev, "Error VBDL failed with ACPI status %d\n", status);
323 }
324 // Check switches after buttons since VBDL may have side effects.
325 if (has_switches)
326 detect_tablet_mode(&device->dev);
327
328 device_init_wakeup(&device->dev, true);
329 /*
330 * In order for system wakeup to work, the EC GPE has to be marked as
331 * a wakeup one, so do that here (this setting will persist, but it has
332 * no effect until the wakeup mask is set for the EC GPE).
333 */
334 acpi_ec_mark_gpe_for_wake();
335 return 0;
336 }
337
intel_vbtn_remove(struct platform_device * device)338 static void intel_vbtn_remove(struct platform_device *device)
339 {
340 acpi_handle handle = ACPI_HANDLE(&device->dev);
341
342 device_init_wakeup(&device->dev, false);
343 acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
344 }
345
intel_vbtn_pm_prepare(struct device * dev)346 static int intel_vbtn_pm_prepare(struct device *dev)
347 {
348 if (device_may_wakeup(dev)) {
349 struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
350
351 priv->wakeup_mode = true;
352 }
353 return 0;
354 }
355
intel_vbtn_pm_complete(struct device * dev)356 static void intel_vbtn_pm_complete(struct device *dev)
357 {
358 struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
359
360 priv->wakeup_mode = false;
361 }
362
intel_vbtn_pm_resume(struct device * dev)363 static int intel_vbtn_pm_resume(struct device *dev)
364 {
365 struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
366
367 intel_vbtn_pm_complete(dev);
368
369 if (priv->has_switches)
370 detect_tablet_mode(dev);
371
372 return 0;
373 }
374
375 static const struct dev_pm_ops intel_vbtn_pm_ops = {
376 .prepare = intel_vbtn_pm_prepare,
377 .complete = intel_vbtn_pm_complete,
378 .resume = intel_vbtn_pm_resume,
379 .restore = intel_vbtn_pm_resume,
380 .thaw = intel_vbtn_pm_resume,
381 };
382
383 static struct platform_driver intel_vbtn_pl_driver = {
384 .driver = {
385 .name = "intel-vbtn",
386 .acpi_match_table = intel_vbtn_ids,
387 .pm = &intel_vbtn_pm_ops,
388 },
389 .probe = intel_vbtn_probe,
390 .remove_new = intel_vbtn_remove,
391 };
392
393 static acpi_status __init
check_acpi_dev(acpi_handle handle,u32 lvl,void * context,void ** rv)394 check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
395 {
396 const struct acpi_device_id *ids = context;
397 struct acpi_device *dev = acpi_fetch_acpi_dev(handle);
398
399 if (dev && acpi_match_device_ids(dev, ids) == 0)
400 if (!IS_ERR_OR_NULL(acpi_create_platform_device(dev, NULL)))
401 dev_info(&dev->dev,
402 "intel-vbtn: created platform device\n");
403
404 return AE_OK;
405 }
406
intel_vbtn_init(void)407 static int __init intel_vbtn_init(void)
408 {
409 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
410 ACPI_UINT32_MAX, check_acpi_dev, NULL,
411 (void *)intel_vbtn_ids, NULL);
412
413 return platform_driver_register(&intel_vbtn_pl_driver);
414 }
415 module_init(intel_vbtn_init);
416
intel_vbtn_exit(void)417 static void __exit intel_vbtn_exit(void)
418 {
419 platform_driver_unregister(&intel_vbtn_pl_driver);
420 }
421 module_exit(intel_vbtn_exit);
422