xref: /linux/drivers/platform/x86/intel/vbtn.c (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
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 		ret = input_register_device(priv->switches_dev);
140 		if (ret)
141 			return ret;
142 	}
143 
144 	return 0;
145 }
146 
147 static void notify_handler(acpi_handle handle, u32 event, void *context)
148 {
149 	struct platform_device *device = context;
150 	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
151 	unsigned int val = !(event & 1); /* Even=press, Odd=release */
152 	const struct key_entry *ke, *ke_rel;
153 	struct input_dev *input_dev;
154 	bool autorelease;
155 	int ret;
156 
157 	if ((ke = sparse_keymap_entry_from_scancode(priv->buttons_dev, event))) {
158 		if (!priv->has_buttons) {
159 			dev_warn(&device->dev, "Warning: received a button event on a device without buttons, please report this.\n");
160 			return;
161 		}
162 		input_dev = priv->buttons_dev;
163 	} else if ((ke = sparse_keymap_entry_from_scancode(priv->switches_dev, event))) {
164 		if (!priv->has_switches) {
165 			/* See dual_accel_detect.h for more info */
166 			if (priv->dual_accel)
167 				return;
168 
169 			dev_info(&device->dev, "Registering Intel Virtual Switches input-dev after receiving a switch event\n");
170 			ret = input_register_device(priv->switches_dev);
171 			if (ret)
172 				return;
173 
174 			priv->has_switches = true;
175 		}
176 		input_dev = priv->switches_dev;
177 	} else {
178 		dev_dbg(&device->dev, "unknown event index 0x%x\n", event);
179 		return;
180 	}
181 
182 	if (priv->wakeup_mode) {
183 		pm_wakeup_hard_event(&device->dev);
184 
185 		/*
186 		 * Skip reporting an evdev event for button wake events,
187 		 * mirroring how the drivers/acpi/button.c code skips this too.
188 		 */
189 		if (ke->type == KE_KEY)
190 			return;
191 	}
192 
193 	/*
194 	 * Even press events are autorelease if there is no corresponding odd
195 	 * release event, or if the odd event is KE_IGNORE.
196 	 */
197 	ke_rel = sparse_keymap_entry_from_scancode(input_dev, event | 1);
198 	autorelease = val && (!ke_rel || ke_rel->type == KE_IGNORE);
199 
200 	sparse_keymap_report_event(input_dev, event, val, autorelease);
201 }
202 
203 /*
204  * There are several laptops (non 2-in-1) models out there which support VGBS,
205  * but simply always return 0, which we translate to SW_TABLET_MODE=1. This in
206  * turn causes userspace (libinput) to suppress events from the builtin
207  * keyboard and touchpad, making the laptop essentially unusable.
208  *
209  * Since the problem of wrongly reporting SW_TABLET_MODE=1 in combination
210  * with libinput, leads to a non-usable system. Where as OTOH many people will
211  * not even notice when SW_TABLET_MODE is not being reported, a DMI based allow
212  * list is used here. This list mainly matches on the chassis-type of 2-in-1s.
213  *
214  * There are also some 2-in-1s which use the intel-vbtn ACPI interface to report
215  * SW_TABLET_MODE with a chassis-type of 8 ("Portable") or 10 ("Notebook"),
216  * these are matched on a per model basis, since many normal laptops with a
217  * possible broken VGBS ACPI-method also use these chassis-types.
218  */
219 static const struct dmi_system_id dmi_switches_allow_list[] = {
220 	{
221 		.matches = {
222 			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "31" /* Convertible */),
223 		},
224 	},
225 	{
226 		.matches = {
227 			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "32" /* Detachable */),
228 		},
229 	},
230 	{
231 		.matches = {
232 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
233 			DMI_MATCH(DMI_PRODUCT_NAME, "Venue 11 Pro 7130"),
234 		},
235 	},
236 	{
237 		.matches = {
238 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
239 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion 13 x360 PC"),
240 		},
241 	},
242 	{
243 		.matches = {
244 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
245 			DMI_MATCH(DMI_PRODUCT_NAME, "Switch SA5-271"),
246 		},
247 	},
248 	{
249 		.matches = {
250 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
251 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7352"),
252 		},
253 	},
254 	{} /* Array terminator */
255 };
256 
257 static bool intel_vbtn_has_switches(acpi_handle handle, bool dual_accel)
258 {
259 	/* See dual_accel_detect.h for more info */
260 	if (dual_accel)
261 		return false;
262 
263 	if (!dmi_check_system(dmi_switches_allow_list))
264 		return false;
265 
266 	return acpi_has_method(handle, "VGBS");
267 }
268 
269 static int intel_vbtn_probe(struct platform_device *device)
270 {
271 	acpi_handle handle = ACPI_HANDLE(&device->dev);
272 	bool dual_accel, has_buttons, has_switches;
273 	struct intel_vbtn_priv *priv;
274 	acpi_status status;
275 	int err;
276 
277 	dual_accel = dual_accel_detect();
278 	has_buttons = acpi_has_method(handle, "VBDL");
279 	has_switches = intel_vbtn_has_switches(handle, dual_accel);
280 
281 	if (!has_buttons && !has_switches) {
282 		dev_warn(&device->dev, "failed to read Intel Virtual Button driver\n");
283 		return -ENODEV;
284 	}
285 
286 	priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
287 	if (!priv)
288 		return -ENOMEM;
289 	dev_set_drvdata(&device->dev, priv);
290 
291 	priv->dual_accel = dual_accel;
292 	priv->has_buttons = has_buttons;
293 	priv->has_switches = has_switches;
294 
295 	err = intel_vbtn_input_setup(device);
296 	if (err) {
297 		pr_err("Failed to setup Intel Virtual Button\n");
298 		return err;
299 	}
300 
301 	status = acpi_install_notify_handler(handle,
302 					     ACPI_DEVICE_NOTIFY,
303 					     notify_handler,
304 					     device);
305 	if (ACPI_FAILURE(status))
306 		return -EBUSY;
307 
308 	if (has_buttons) {
309 		status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
310 		if (ACPI_FAILURE(status))
311 			dev_err(&device->dev, "Error VBDL failed with ACPI status %d\n", status);
312 	}
313 	// Check switches after buttons since VBDL may have side effects.
314 	if (has_switches)
315 		detect_tablet_mode(&device->dev);
316 
317 	device_init_wakeup(&device->dev, true);
318 	/*
319 	 * In order for system wakeup to work, the EC GPE has to be marked as
320 	 * a wakeup one, so do that here (this setting will persist, but it has
321 	 * no effect until the wakeup mask is set for the EC GPE).
322 	 */
323 	acpi_ec_mark_gpe_for_wake();
324 	return 0;
325 }
326 
327 static void intel_vbtn_remove(struct platform_device *device)
328 {
329 	acpi_handle handle = ACPI_HANDLE(&device->dev);
330 
331 	device_init_wakeup(&device->dev, false);
332 	acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
333 }
334 
335 static int intel_vbtn_pm_prepare(struct device *dev)
336 {
337 	if (device_may_wakeup(dev)) {
338 		struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
339 
340 		priv->wakeup_mode = true;
341 	}
342 	return 0;
343 }
344 
345 static void intel_vbtn_pm_complete(struct device *dev)
346 {
347 	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
348 
349 	priv->wakeup_mode = false;
350 }
351 
352 static int intel_vbtn_pm_resume(struct device *dev)
353 {
354 	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
355 
356 	intel_vbtn_pm_complete(dev);
357 
358 	if (priv->has_switches)
359 		detect_tablet_mode(dev);
360 
361 	return 0;
362 }
363 
364 static const struct dev_pm_ops intel_vbtn_pm_ops = {
365 	.prepare = intel_vbtn_pm_prepare,
366 	.complete = intel_vbtn_pm_complete,
367 	.resume = intel_vbtn_pm_resume,
368 	.restore = intel_vbtn_pm_resume,
369 	.thaw = intel_vbtn_pm_resume,
370 };
371 
372 static struct platform_driver intel_vbtn_pl_driver = {
373 	.driver = {
374 		.name = "intel-vbtn",
375 		.acpi_match_table = intel_vbtn_ids,
376 		.pm = &intel_vbtn_pm_ops,
377 	},
378 	.probe = intel_vbtn_probe,
379 	.remove_new = intel_vbtn_remove,
380 };
381 
382 static acpi_status __init
383 check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
384 {
385 	const struct acpi_device_id *ids = context;
386 	struct acpi_device *dev = acpi_fetch_acpi_dev(handle);
387 
388 	if (dev && acpi_match_device_ids(dev, ids) == 0)
389 		if (!IS_ERR_OR_NULL(acpi_create_platform_device(dev, NULL)))
390 			dev_info(&dev->dev,
391 				 "intel-vbtn: created platform device\n");
392 
393 	return AE_OK;
394 }
395 
396 static int __init intel_vbtn_init(void)
397 {
398 	acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
399 			    ACPI_UINT32_MAX, check_acpi_dev, NULL,
400 			    (void *)intel_vbtn_ids, NULL);
401 
402 	return platform_driver_register(&intel_vbtn_pl_driver);
403 }
404 module_init(intel_vbtn_init);
405 
406 static void __exit intel_vbtn_exit(void)
407 {
408 	platform_driver_unregister(&intel_vbtn_pl_driver);
409 }
410 module_exit(intel_vbtn_exit);
411