xref: /linux/drivers/platform/x86/intel/vbtn.c (revision 7354eb7f1558466e92e926802d36e69e42938ea9)
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_DESCRIPTION("Intel Virtual Button driver");
28 MODULE_LICENSE("GPL");
29 MODULE_AUTHOR("AceLan Kao");
30 
31 static const struct acpi_device_id intel_vbtn_ids[] = {
32 	{"INT33D6", 0},
33 	{"", 0},
34 };
35 MODULE_DEVICE_TABLE(acpi, intel_vbtn_ids);
36 
37 /* In theory, these are HID usages. */
38 static const struct key_entry intel_vbtn_keymap[] = {
39 	{ KE_KEY, 0xC0, { KEY_POWER } },	/* power key press */
40 	{ KE_IGNORE, 0xC1, { KEY_POWER } },	/* power key release */
41 	{ KE_KEY, 0xC2, { KEY_LEFTMETA } },		/* 'Windows' key press */
42 	{ KE_KEY, 0xC3, { KEY_LEFTMETA } },		/* 'Windows' key release */
43 	{ KE_KEY, 0xC4, { KEY_VOLUMEUP } },		/* volume-up key press */
44 	{ KE_IGNORE, 0xC5, { KEY_VOLUMEUP } },		/* volume-up key release */
45 	{ KE_KEY, 0xC6, { KEY_VOLUMEDOWN } },		/* volume-down key press */
46 	{ KE_IGNORE, 0xC7, { KEY_VOLUMEDOWN } },	/* volume-down key release */
47 	{ KE_KEY,    0xC8, { KEY_ROTATE_LOCK_TOGGLE } },	/* rotate-lock key press */
48 	{ KE_KEY,    0xC9, { KEY_ROTATE_LOCK_TOGGLE } },	/* rotate-lock key release */
49 	{ KE_END }
50 };
51 
52 static const struct key_entry intel_vbtn_switchmap[] = {
53 	/*
54 	 * SW_DOCK should only be reported for docking stations, but DSDTs using the
55 	 * intel-vbtn code, always seem to use this for 2-in-1s / convertibles and set
56 	 * SW_DOCK=1 when in laptop-mode (in tandem with setting SW_TABLET_MODE=0).
57 	 * This causes userspace to think the laptop is docked to a port-replicator
58 	 * and to disable suspend-on-lid-close, which is undesirable.
59 	 * Map the dock events to KEY_IGNORE to avoid this broken SW_DOCK reporting.
60 	 */
61 	{ KE_IGNORE, 0xCA, { .sw = { SW_DOCK, 1 } } },		/* Docked */
62 	{ KE_IGNORE, 0xCB, { .sw = { SW_DOCK, 0 } } },		/* Undocked */
63 	{ KE_SW,     0xCC, { .sw = { SW_TABLET_MODE, 1 } } },	/* Tablet */
64 	{ KE_SW,     0xCD, { .sw = { SW_TABLET_MODE, 0 } } },	/* Laptop */
65 	{ KE_END }
66 };
67 
68 struct intel_vbtn_priv {
69 	struct input_dev *buttons_dev;
70 	struct input_dev *switches_dev;
71 	bool dual_accel;
72 	bool has_buttons;
73 	bool has_switches;
74 	bool wakeup_mode;
75 };
76 
77 static void detect_tablet_mode(struct device *dev)
78 {
79 	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
80 	acpi_handle handle = ACPI_HANDLE(dev);
81 	unsigned long long vgbs;
82 	acpi_status status;
83 	int m;
84 
85 	status = acpi_evaluate_integer(handle, "VGBS", NULL, &vgbs);
86 	if (ACPI_FAILURE(status))
87 		return;
88 
89 	m = !(vgbs & VGBS_TABLET_MODE_FLAGS);
90 	input_report_switch(priv->switches_dev, SW_TABLET_MODE, m);
91 	m = (vgbs & VGBS_DOCK_MODE_FLAG) ? 1 : 0;
92 	input_report_switch(priv->switches_dev, SW_DOCK, m);
93 
94 	input_sync(priv->switches_dev);
95 }
96 
97 /*
98  * Note this unconditionally creates the 2 input_dev-s and sets up
99  * the sparse-keymaps. Only the registration is conditional on
100  * have_buttons / have_switches. This is done so that the notify
101  * handler can always call sparse_keymap_entry_from_scancode()
102  * on the input_dev-s do determine the event type.
103  */
104 static int intel_vbtn_input_setup(struct platform_device *device)
105 {
106 	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
107 	int ret;
108 
109 	priv->buttons_dev = devm_input_allocate_device(&device->dev);
110 	if (!priv->buttons_dev)
111 		return -ENOMEM;
112 
113 	ret = sparse_keymap_setup(priv->buttons_dev, intel_vbtn_keymap, NULL);
114 	if (ret)
115 		return ret;
116 
117 	priv->buttons_dev->dev.parent = &device->dev;
118 	priv->buttons_dev->name = "Intel Virtual Buttons";
119 	priv->buttons_dev->id.bustype = BUS_HOST;
120 
121 	if (priv->has_buttons) {
122 		ret = input_register_device(priv->buttons_dev);
123 		if (ret)
124 			return ret;
125 	}
126 
127 	priv->switches_dev = devm_input_allocate_device(&device->dev);
128 	if (!priv->switches_dev)
129 		return -ENOMEM;
130 
131 	ret = sparse_keymap_setup(priv->switches_dev, intel_vbtn_switchmap, NULL);
132 	if (ret)
133 		return ret;
134 
135 	priv->switches_dev->dev.parent = &device->dev;
136 	priv->switches_dev->name = "Intel Virtual Switches";
137 	priv->switches_dev->id.bustype = BUS_HOST;
138 
139 	if (priv->has_switches) {
140 		ret = input_register_device(priv->switches_dev);
141 		if (ret)
142 			return ret;
143 	}
144 
145 	return 0;
146 }
147 
148 static void notify_handler(acpi_handle handle, u32 event, void *context)
149 {
150 	struct platform_device *device = context;
151 	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
152 	unsigned int val = !(event & 1); /* Even=press, Odd=release */
153 	const struct key_entry *ke, *ke_rel;
154 	struct input_dev *input_dev;
155 	bool autorelease;
156 	int ret;
157 
158 	if ((ke = sparse_keymap_entry_from_scancode(priv->buttons_dev, event))) {
159 		if (!priv->has_buttons) {
160 			dev_warn(&device->dev, "Warning: received 0x%02x button event on a device without buttons, please report this.\n",
161 				 event);
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 
205 /*
206  * There are several laptops (non 2-in-1) models out there which support VGBS,
207  * but simply always return 0, which we translate to SW_TABLET_MODE=1. This in
208  * turn causes userspace (libinput) to suppress events from the builtin
209  * keyboard and touchpad, making the laptop essentially unusable.
210  *
211  * Since the problem of wrongly reporting SW_TABLET_MODE=1 in combination
212  * with libinput, leads to a non-usable system. Where as OTOH many people will
213  * not even notice when SW_TABLET_MODE is not being reported, a DMI based allow
214  * list is used here. This list mainly matches on the chassis-type of 2-in-1s.
215  *
216  * There are also some 2-in-1s which use the intel-vbtn ACPI interface to report
217  * SW_TABLET_MODE with a chassis-type of 8 ("Portable") or 10 ("Notebook"),
218  * these are matched on a per model basis, since many normal laptops with a
219  * possible broken VGBS ACPI-method also use these chassis-types.
220  */
221 static const struct dmi_system_id dmi_switches_allow_list[] = {
222 	{
223 		.matches = {
224 			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "31" /* Convertible */),
225 		},
226 	},
227 	{
228 		.matches = {
229 			DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "32" /* Detachable */),
230 		},
231 	},
232 	{
233 		.matches = {
234 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
235 			DMI_MATCH(DMI_PRODUCT_NAME, "Venue 11 Pro 7130"),
236 		},
237 	},
238 	{
239 		.matches = {
240 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
241 			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion 13 x360 PC"),
242 		},
243 	},
244 	{
245 		.matches = {
246 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
247 			DMI_MATCH(DMI_PRODUCT_NAME, "Switch SA5-271"),
248 		},
249 	},
250 	{
251 		.matches = {
252 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
253 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7352"),
254 		},
255 	},
256 	{} /* Array terminator */
257 };
258 
259 static bool intel_vbtn_has_switches(acpi_handle handle, bool dual_accel)
260 {
261 	/* See dual_accel_detect.h for more info */
262 	if (dual_accel)
263 		return false;
264 
265 	if (!dmi_check_system(dmi_switches_allow_list))
266 		return false;
267 
268 	return acpi_has_method(handle, "VGBS");
269 }
270 
271 static int intel_vbtn_probe(struct platform_device *device)
272 {
273 	acpi_handle handle = ACPI_HANDLE(&device->dev);
274 	bool dual_accel, has_buttons, has_switches;
275 	struct intel_vbtn_priv *priv;
276 	acpi_status status;
277 	int err;
278 
279 	dual_accel = dual_accel_detect();
280 	has_buttons = acpi_has_method(handle, "VBDL");
281 	has_switches = intel_vbtn_has_switches(handle, dual_accel);
282 
283 	if (!has_buttons && !has_switches) {
284 		dev_warn(&device->dev, "failed to read Intel Virtual Button driver\n");
285 		return -ENODEV;
286 	}
287 
288 	priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
289 	if (!priv)
290 		return -ENOMEM;
291 	dev_set_drvdata(&device->dev, priv);
292 
293 	priv->dual_accel = dual_accel;
294 	priv->has_buttons = has_buttons;
295 	priv->has_switches = has_switches;
296 
297 	err = intel_vbtn_input_setup(device);
298 	if (err) {
299 		pr_err("Failed to setup Intel Virtual Button\n");
300 		return err;
301 	}
302 
303 	status = acpi_install_notify_handler(handle,
304 					     ACPI_DEVICE_NOTIFY,
305 					     notify_handler,
306 					     device);
307 	if (ACPI_FAILURE(status))
308 		return -EBUSY;
309 
310 	if (has_buttons) {
311 		status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
312 		if (ACPI_FAILURE(status))
313 			dev_err(&device->dev, "Error VBDL failed with ACPI status %d\n", status);
314 	}
315 	// Check switches after buttons since VBDL may have side effects.
316 	if (has_switches)
317 		detect_tablet_mode(&device->dev);
318 
319 	device_init_wakeup(&device->dev, true);
320 	/*
321 	 * In order for system wakeup to work, the EC GPE has to be marked as
322 	 * a wakeup one, so do that here (this setting will persist, but it has
323 	 * no effect until the wakeup mask is set for the EC GPE).
324 	 */
325 	acpi_ec_mark_gpe_for_wake();
326 	return 0;
327 }
328 
329 static void intel_vbtn_remove(struct platform_device *device)
330 {
331 	acpi_handle handle = ACPI_HANDLE(&device->dev);
332 
333 	device_init_wakeup(&device->dev, false);
334 	acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
335 }
336 
337 static int intel_vbtn_pm_prepare(struct device *dev)
338 {
339 	if (device_may_wakeup(dev)) {
340 		struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
341 
342 		priv->wakeup_mode = true;
343 	}
344 	return 0;
345 }
346 
347 static void intel_vbtn_pm_complete(struct device *dev)
348 {
349 	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
350 
351 	priv->wakeup_mode = false;
352 }
353 
354 static int intel_vbtn_pm_resume(struct device *dev)
355 {
356 	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
357 
358 	intel_vbtn_pm_complete(dev);
359 
360 	if (priv->has_switches)
361 		detect_tablet_mode(dev);
362 
363 	return 0;
364 }
365 
366 static const struct dev_pm_ops intel_vbtn_pm_ops = {
367 	.prepare = intel_vbtn_pm_prepare,
368 	.complete = intel_vbtn_pm_complete,
369 	.resume = intel_vbtn_pm_resume,
370 	.restore = intel_vbtn_pm_resume,
371 	.thaw = intel_vbtn_pm_resume,
372 };
373 
374 static struct platform_driver intel_vbtn_pl_driver = {
375 	.driver = {
376 		.name = "intel-vbtn",
377 		.acpi_match_table = intel_vbtn_ids,
378 		.pm = &intel_vbtn_pm_ops,
379 	},
380 	.probe = intel_vbtn_probe,
381 	.remove_new = intel_vbtn_remove,
382 };
383 
384 static acpi_status __init
385 check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
386 {
387 	const struct acpi_device_id *ids = context;
388 	struct acpi_device *dev = acpi_fetch_acpi_dev(handle);
389 
390 	if (dev && acpi_match_device_ids(dev, ids) == 0)
391 		if (!IS_ERR_OR_NULL(acpi_create_platform_device(dev, NULL)))
392 			dev_info(&dev->dev,
393 				 "intel-vbtn: created platform device\n");
394 
395 	return AE_OK;
396 }
397 
398 static int __init intel_vbtn_init(void)
399 {
400 	acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
401 			    ACPI_UINT32_MAX, check_acpi_dev, NULL,
402 			    (void *)intel_vbtn_ids, NULL);
403 
404 	return platform_driver_register(&intel_vbtn_pl_driver);
405 }
406 module_init(intel_vbtn_init);
407 
408 static void __exit intel_vbtn_exit(void)
409 {
410 	platform_driver_unregister(&intel_vbtn_pl_driver);
411 }
412 module_exit(intel_vbtn_exit);
413