xref: /linux/drivers/platform/x86/intel/vbtn.c (revision c4101e55974cc7d835fbd2d8e01553a3f61e9e75)
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 #include "../dual_accel_detect.h"
18 
19 /* Returned when NOT in tablet mode on some HP Stream x360 11 models */
20 #define VGBS_TABLET_MODE_FLAG_ALT	0x10
21 /* When NOT in tablet mode, VGBS returns with the flag 0x40 */
22 #define VGBS_TABLET_MODE_FLAG		0x40
23 #define VGBS_DOCK_MODE_FLAG		0x80
24 
25 #define VGBS_TABLET_MODE_FLAGS (VGBS_TABLET_MODE_FLAG | VGBS_TABLET_MODE_FLAG_ALT)
26 
27 MODULE_LICENSE("GPL");
28 MODULE_AUTHOR("AceLan Kao");
29 
30 static const struct acpi_device_id intel_vbtn_ids[] = {
31 	{"INT33D6", 0},
32 	{"", 0},
33 };
34 MODULE_DEVICE_TABLE(acpi, intel_vbtn_ids);
35 
36 /* In theory, these are HID usages. */
37 static const struct key_entry intel_vbtn_keymap[] = {
38 	{ KE_KEY, 0xC0, { KEY_POWER } },	/* power key press */
39 	{ KE_IGNORE, 0xC1, { KEY_POWER } },	/* power key release */
40 	{ KE_KEY, 0xC2, { KEY_LEFTMETA } },		/* 'Windows' key press */
41 	{ KE_KEY, 0xC3, { KEY_LEFTMETA } },		/* 'Windows' key release */
42 	{ KE_KEY, 0xC4, { KEY_VOLUMEUP } },		/* volume-up key press */
43 	{ KE_IGNORE, 0xC5, { KEY_VOLUMEUP } },		/* volume-up key release */
44 	{ KE_KEY, 0xC6, { KEY_VOLUMEDOWN } },		/* volume-down key press */
45 	{ KE_IGNORE, 0xC7, { KEY_VOLUMEDOWN } },	/* volume-down key release */
46 	{ KE_KEY,    0xC8, { KEY_ROTATE_LOCK_TOGGLE } },	/* rotate-lock key press */
47 	{ KE_KEY,    0xC9, { KEY_ROTATE_LOCK_TOGGLE } },	/* rotate-lock key release */
48 	{ KE_END }
49 };
50 
51 static const struct key_entry intel_vbtn_switchmap[] = {
52 	/*
53 	 * SW_DOCK should only be reported for docking stations, but DSDTs using the
54 	 * intel-vbtn code, always seem to use this for 2-in-1s / convertibles and set
55 	 * SW_DOCK=1 when in laptop-mode (in tandem with setting SW_TABLET_MODE=0).
56 	 * This causes userspace to think the laptop is docked to a port-replicator
57 	 * and to disable suspend-on-lid-close, which is undesirable.
58 	 * Map the dock events to KEY_IGNORE to avoid this broken SW_DOCK reporting.
59 	 */
60 	{ KE_IGNORE, 0xCA, { .sw = { SW_DOCK, 1 } } },		/* Docked */
61 	{ KE_IGNORE, 0xCB, { .sw = { SW_DOCK, 0 } } },		/* Undocked */
62 	{ KE_SW,     0xCC, { .sw = { SW_TABLET_MODE, 1 } } },	/* Tablet */
63 	{ KE_SW,     0xCD, { .sw = { SW_TABLET_MODE, 0 } } },	/* Laptop */
64 	{ KE_END }
65 };
66 
67 struct intel_vbtn_priv {
68 	struct input_dev *buttons_dev;
69 	struct input_dev *switches_dev;
70 	bool dual_accel;
71 	bool has_buttons;
72 	bool has_switches;
73 	bool wakeup_mode;
74 };
75 
76 static void detect_tablet_mode(struct device *dev)
77 {
78 	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
79 	acpi_handle handle = ACPI_HANDLE(dev);
80 	unsigned long long vgbs;
81 	acpi_status status;
82 	int m;
83 
84 	status = acpi_evaluate_integer(handle, "VGBS", NULL, &vgbs);
85 	if (ACPI_FAILURE(status))
86 		return;
87 
88 	m = !(vgbs & VGBS_TABLET_MODE_FLAGS);
89 	input_report_switch(priv->switches_dev, SW_TABLET_MODE, m);
90 	m = (vgbs & VGBS_DOCK_MODE_FLAG) ? 1 : 0;
91 	input_report_switch(priv->switches_dev, SW_DOCK, m);
92 
93 	input_sync(priv->switches_dev);
94 }
95 
96 /*
97  * Note this unconditionally creates the 2 input_dev-s and sets up
98  * the sparse-keymaps. Only the registration is conditional on
99  * have_buttons / have_switches. This is done so that the notify
100  * handler can always call sparse_keymap_entry_from_scancode()
101  * on the input_dev-s do determine the event type.
102  */
103 static int intel_vbtn_input_setup(struct platform_device *device)
104 {
105 	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
106 	int ret;
107 
108 	priv->buttons_dev = devm_input_allocate_device(&device->dev);
109 	if (!priv->buttons_dev)
110 		return -ENOMEM;
111 
112 	ret = sparse_keymap_setup(priv->buttons_dev, intel_vbtn_keymap, NULL);
113 	if (ret)
114 		return ret;
115 
116 	priv->buttons_dev->dev.parent = &device->dev;
117 	priv->buttons_dev->name = "Intel Virtual Buttons";
118 	priv->buttons_dev->id.bustype = BUS_HOST;
119 
120 	if (priv->has_buttons) {
121 		ret = input_register_device(priv->buttons_dev);
122 		if (ret)
123 			return ret;
124 	}
125 
126 	priv->switches_dev = devm_input_allocate_device(&device->dev);
127 	if (!priv->switches_dev)
128 		return -ENOMEM;
129 
130 	ret = sparse_keymap_setup(priv->switches_dev, intel_vbtn_switchmap, NULL);
131 	if (ret)
132 		return ret;
133 
134 	priv->switches_dev->dev.parent = &device->dev;
135 	priv->switches_dev->name = "Intel Virtual Switches";
136 	priv->switches_dev->id.bustype = BUS_HOST;
137 
138 	if (priv->has_switches) {
139 		detect_tablet_mode(&device->dev);
140 
141 		ret = input_register_device(priv->switches_dev);
142 		if (ret)
143 			return ret;
144 	}
145 
146 	return 0;
147 }
148 
149 static void notify_handler(acpi_handle handle, u32 event, void *context)
150 {
151 	struct platform_device *device = context;
152 	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
153 	unsigned int val = !(event & 1); /* Even=press, Odd=release */
154 	const struct key_entry *ke, *ke_rel;
155 	struct input_dev *input_dev;
156 	bool autorelease;
157 	int ret;
158 
159 	if ((ke = sparse_keymap_entry_from_scancode(priv->buttons_dev, event))) {
160 		if (!priv->has_buttons) {
161 			dev_warn(&device->dev, "Warning: received a button event on a device without buttons, please report this.\n");
162 			return;
163 		}
164 		input_dev = priv->buttons_dev;
165 	} else if ((ke = sparse_keymap_entry_from_scancode(priv->switches_dev, event))) {
166 		if (!priv->has_switches) {
167 			/* See dual_accel_detect.h for more info */
168 			if (priv->dual_accel)
169 				return;
170 
171 			dev_info(&device->dev, "Registering Intel Virtual Switches input-dev after receiving a switch event\n");
172 			ret = input_register_device(priv->switches_dev);
173 			if (ret)
174 				return;
175 
176 			priv->has_switches = true;
177 		}
178 		input_dev = priv->switches_dev;
179 	} else {
180 		dev_dbg(&device->dev, "unknown event index 0x%x\n", event);
181 		return;
182 	}
183 
184 	if (priv->wakeup_mode) {
185 		pm_wakeup_hard_event(&device->dev);
186 
187 		/*
188 		 * Skip reporting an evdev event for button wake events,
189 		 * mirroring how the drivers/acpi/button.c code skips this too.
190 		 */
191 		if (ke->type == KE_KEY)
192 			return;
193 	}
194 
195 	/*
196 	 * Even press events are autorelease if there is no corresponding odd
197 	 * release event, or if the odd event is KE_IGNORE.
198 	 */
199 	ke_rel = sparse_keymap_entry_from_scancode(input_dev, event | 1);
200 	autorelease = val && (!ke_rel || ke_rel->type == KE_IGNORE);
201 
202 	sparse_keymap_report_event(input_dev, event, val, autorelease);
203 
204 	/* Some devices need this to report further events */
205 	acpi_evaluate_object(handle, "VBDL", NULL, NULL);
206 }
207 
208 /*
209  * There are several laptops (non 2-in-1) models out there which support VGBS,
210  * but simply always return 0, which we translate to SW_TABLET_MODE=1. This in
211  * turn causes userspace (libinput) to suppress events from the builtin
212  * keyboard and touchpad, making the laptop essentially unusable.
213  *
214  * Since the problem of wrongly reporting SW_TABLET_MODE=1 in combination
215  * with libinput, leads to a non-usable system. Where as OTOH many people will
216  * not even notice when SW_TABLET_MODE is not being reported, a DMI based allow
217  * list is used here. This list mainly matches on the chassis-type of 2-in-1s.
218  *
219  * There are also some 2-in-1s which use the intel-vbtn ACPI interface to report
220  * SW_TABLET_MODE with a chassis-type of 8 ("Portable") or 10 ("Notebook"),
221  * these are matched on a per model basis, since many normal laptops with a
222  * possible broken VGBS ACPI-method also use these chassis-types.
223  */
224 static const struct dmi_system_id dmi_switches_allow_list[] = {
225 	{
226 		.matches = {
227 			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "31" /* Convertible */),
228 		},
229 	},
230 	{
231 		.matches = {
232 			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "32" /* Detachable */),
233 		},
234 	},
235 	{
236 		.matches = {
237 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
238 			DMI_MATCH(DMI_PRODUCT_NAME, "Venue 11 Pro 7130"),
239 		},
240 	},
241 	{
242 		.matches = {
243 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
244 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion 13 x360 PC"),
245 		},
246 	},
247 	{
248 		.matches = {
249 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
250 			DMI_MATCH(DMI_PRODUCT_NAME, "Switch SA5-271"),
251 		},
252 	},
253 	{
254 		.matches = {
255 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
256 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7352"),
257 		},
258 	},
259 	{} /* Array terminator */
260 };
261 
262 static bool intel_vbtn_has_switches(acpi_handle handle, bool dual_accel)
263 {
264 	unsigned long long vgbs;
265 	acpi_status status;
266 
267 	/* See dual_accel_detect.h for more info */
268 	if (dual_accel)
269 		return false;
270 
271 	if (!dmi_check_system(dmi_switches_allow_list))
272 		return false;
273 
274 	status = acpi_evaluate_integer(handle, "VGBS", NULL, &vgbs);
275 	return ACPI_SUCCESS(status);
276 }
277 
278 static int intel_vbtn_probe(struct platform_device *device)
279 {
280 	acpi_handle handle = ACPI_HANDLE(&device->dev);
281 	bool dual_accel, has_buttons, has_switches;
282 	struct intel_vbtn_priv *priv;
283 	acpi_status status;
284 	int err;
285 
286 	dual_accel = dual_accel_detect();
287 	has_buttons = acpi_has_method(handle, "VBDL");
288 	has_switches = intel_vbtn_has_switches(handle, dual_accel);
289 
290 	if (!has_buttons && !has_switches) {
291 		dev_warn(&device->dev, "failed to read Intel Virtual Button driver\n");
292 		return -ENODEV;
293 	}
294 
295 	priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
296 	if (!priv)
297 		return -ENOMEM;
298 	dev_set_drvdata(&device->dev, priv);
299 
300 	priv->dual_accel = dual_accel;
301 	priv->has_buttons = has_buttons;
302 	priv->has_switches = has_switches;
303 
304 	err = intel_vbtn_input_setup(device);
305 	if (err) {
306 		pr_err("Failed to setup Intel Virtual Button\n");
307 		return err;
308 	}
309 
310 	status = acpi_install_notify_handler(handle,
311 					     ACPI_DEVICE_NOTIFY,
312 					     notify_handler,
313 					     device);
314 	if (ACPI_FAILURE(status))
315 		return -EBUSY;
316 
317 	if (has_buttons) {
318 		status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
319 		if (ACPI_FAILURE(status))
320 			dev_err(&device->dev, "Error VBDL failed with ACPI status %d\n", status);
321 	}
322 
323 	device_init_wakeup(&device->dev, true);
324 	/*
325 	 * In order for system wakeup to work, the EC GPE has to be marked as
326 	 * a wakeup one, so do that here (this setting will persist, but it has
327 	 * no effect until the wakeup mask is set for the EC GPE).
328 	 */
329 	acpi_ec_mark_gpe_for_wake();
330 	return 0;
331 }
332 
333 static void intel_vbtn_remove(struct platform_device *device)
334 {
335 	acpi_handle handle = ACPI_HANDLE(&device->dev);
336 
337 	device_init_wakeup(&device->dev, false);
338 	acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
339 }
340 
341 static int intel_vbtn_pm_prepare(struct device *dev)
342 {
343 	if (device_may_wakeup(dev)) {
344 		struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
345 
346 		priv->wakeup_mode = true;
347 	}
348 	return 0;
349 }
350 
351 static void intel_vbtn_pm_complete(struct device *dev)
352 {
353 	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
354 
355 	priv->wakeup_mode = false;
356 }
357 
358 static int intel_vbtn_pm_resume(struct device *dev)
359 {
360 	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
361 
362 	intel_vbtn_pm_complete(dev);
363 
364 	if (priv->has_switches)
365 		detect_tablet_mode(dev);
366 
367 	return 0;
368 }
369 
370 static const struct dev_pm_ops intel_vbtn_pm_ops = {
371 	.prepare = intel_vbtn_pm_prepare,
372 	.complete = intel_vbtn_pm_complete,
373 	.resume = intel_vbtn_pm_resume,
374 	.restore = intel_vbtn_pm_resume,
375 	.thaw = intel_vbtn_pm_resume,
376 };
377 
378 static struct platform_driver intel_vbtn_pl_driver = {
379 	.driver = {
380 		.name = "intel-vbtn",
381 		.acpi_match_table = intel_vbtn_ids,
382 		.pm = &intel_vbtn_pm_ops,
383 	},
384 	.probe = intel_vbtn_probe,
385 	.remove_new = intel_vbtn_remove,
386 };
387 
388 static acpi_status __init
389 check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
390 {
391 	const struct acpi_device_id *ids = context;
392 	struct acpi_device *dev = acpi_fetch_acpi_dev(handle);
393 
394 	if (dev && acpi_match_device_ids(dev, ids) == 0)
395 		if (!IS_ERR_OR_NULL(acpi_create_platform_device(dev, NULL)))
396 			dev_info(&dev->dev,
397 				 "intel-vbtn: created platform device\n");
398 
399 	return AE_OK;
400 }
401 
402 static int __init intel_vbtn_init(void)
403 {
404 	acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
405 			    ACPI_UINT32_MAX, check_acpi_dev, NULL,
406 			    (void *)intel_vbtn_ids, NULL);
407 
408 	return platform_driver_register(&intel_vbtn_pl_driver);
409 }
410 module_init(intel_vbtn_init);
411 
412 static void __exit intel_vbtn_exit(void)
413 {
414 	platform_driver_unregister(&intel_vbtn_pl_driver);
415 }
416 module_exit(intel_vbtn_exit);
417