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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Supports for the button array on SoC tablets originally running
  4 * Windows 8.
  5 *
  6 * (C) Copyright 2014 Intel Corporation
  7 */
  8
  9#include <linux/module.h>
 10#include <linux/input.h>
 11#include <linux/init.h>
 12#include <linux/irq.h>
 13#include <linux/kernel.h>
 14#include <linux/acpi.h>
 15#include <linux/dmi.h>
 16#include <linux/gpio/consumer.h>
 17#include <linux/gpio_keys.h>
 18#include <linux/gpio.h>
 19#include <linux/platform_device.h>
 20
 21static bool use_low_level_irq;
 22module_param(use_low_level_irq, bool, 0444);
 23MODULE_PARM_DESC(use_low_level_irq, "Use low-level triggered IRQ instead of edge triggered");
 24
 25struct soc_button_info {
 26	const char *name;
 27	int acpi_index;
 28	unsigned int event_type;
 29	unsigned int event_code;
 30	bool autorepeat;
 31	bool wakeup;
 32	bool active_low;
 33};
 34
 35struct soc_device_data {
 36	const struct soc_button_info *button_info;
 37	int (*check)(struct device *dev);
 38};
 39
 40/*
 41 * Some of the buttons like volume up/down are auto repeat, while others
 42 * are not. To support both, we register two platform devices, and put
 43 * buttons into them based on whether the key should be auto repeat.
 44 */
 45#define BUTTON_TYPES	2
 46
 47struct soc_button_data {
 48	struct platform_device *children[BUTTON_TYPES];
 49};
 50
 51/*
 52 * Some 2-in-1s which use the soc_button_array driver have this ugly issue in
 53 * their DSDT where the _LID method modifies the irq-type settings of the GPIOs
 54 * used for the power and home buttons. The intend of this AML code is to
 55 * disable these buttons when the lid is closed.
 56 * The AML does this by directly poking the GPIO controllers registers. This is
 57 * problematic because when re-enabling the irq, which happens whenever _LID
 58 * gets called with the lid open (e.g. on boot and on resume), it sets the
 59 * irq-type to IRQ_TYPE_LEVEL_LOW. Where as the gpio-keys driver programs the
 60 * type to, and expects it to be, IRQ_TYPE_EDGE_BOTH.
 61 * To work around this we don't set gpio_keys_button.gpio on these 2-in-1s,
 62 * instead we get the irq for the GPIO ourselves, configure it as
 63 * IRQ_TYPE_LEVEL_LOW (to match how the _LID AML code configures it) and pass
 64 * the irq in gpio_keys_button.irq. Below is a list of affected devices.
 65 */
 66static const struct dmi_system_id dmi_use_low_level_irq[] = {
 67	{
 68		/*
 69		 * Acer Switch 10 SW5-012. _LID method messes with home- and
 70		 * power-button GPIO IRQ settings. When (re-)enabling the irq
 71		 * it ors in its own flags without clearing the previous set
 72		 * ones, leading to an irq-type of IRQ_TYPE_LEVEL_LOW |
 73		 * IRQ_TYPE_LEVEL_HIGH causing a continuous interrupt storm.
 74		 */
 75		.matches = {
 76			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 77			DMI_MATCH(DMI_PRODUCT_NAME, "Aspire SW5-012"),
 78		},
 79	},
 80	{
 81		/* Acer Switch V 10 SW5-017, same issue as Acer Switch 10 SW5-012. */
 82		.matches = {
 83			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 84			DMI_MATCH(DMI_PRODUCT_NAME, "SW5-017"),
 85		},
 86	},
 87	{
 88		/*
 89		 * Acer One S1003. _LID method messes with power-button GPIO
 90		 * IRQ settings, leading to a non working power-button.
 91		 */
 92		.matches = {
 93			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 94			DMI_MATCH(DMI_PRODUCT_NAME, "One S1003"),
 95		},
 96	},
 97	{
 98		/*
 99		 * Lenovo Yoga Tab2 1051F/1051L, something messes with the home-button
100		 * IRQ settings, leading to a non working home-button.
101		 */
102		.matches = {
103			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
104			DMI_MATCH(DMI_PRODUCT_NAME, "60073"),
105			DMI_MATCH(DMI_PRODUCT_VERSION, "1051"),
106		},
107	},
108	{} /* Terminating entry */
109};
110
111/*
112 * Some devices have a wrong entry which points to a GPIO which is
113 * required in another driver, so this driver must not claim it.
114 */
115static const struct dmi_system_id dmi_invalid_acpi_index[] = {
116	{
117		/*
118		 * Lenovo Yoga Book X90F / X90L, the PNP0C40 home button entry
119		 * points to a GPIO which is not a home button and which is
120		 * required by the lenovo-yogabook driver.
121		 */
122		.matches = {
123			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Intel Corporation"),
124			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "CHERRYVIEW D1 PLATFORM"),
125			DMI_EXACT_MATCH(DMI_PRODUCT_VERSION, "YETI-11"),
126		},
127		.driver_data = (void *)1l,
128	},
129	{} /* Terminating entry */
130};
131
132/*
133 * Get the Nth GPIO number from the ACPI object.
134 */
135static int soc_button_lookup_gpio(struct device *dev, int acpi_index,
136				  int *gpio_ret, int *irq_ret)
137{
138	struct gpio_desc *desc;
139
140	desc = gpiod_get_index(dev, NULL, acpi_index, GPIOD_ASIS);
141	if (IS_ERR(desc))
142		return PTR_ERR(desc);
143
144	*gpio_ret = desc_to_gpio(desc);
145	*irq_ret = gpiod_to_irq(desc);
146
147	gpiod_put(desc);
148
149	return 0;
150}
151
152static struct platform_device *
153soc_button_device_create(struct platform_device *pdev,
154			 const struct soc_button_info *button_info,
155			 bool autorepeat)
156{
157	const struct soc_button_info *info;
158	struct platform_device *pd;
159	struct gpio_keys_button *gpio_keys;
160	struct gpio_keys_platform_data *gpio_keys_pdata;
161	const struct dmi_system_id *dmi_id;
162	int invalid_acpi_index = -1;
163	int error, gpio, irq;
164	int n_buttons = 0;
165
166	for (info = button_info; info->name; info++)
167		if (info->autorepeat == autorepeat)
168			n_buttons++;
169
170	gpio_keys_pdata = devm_kzalloc(&pdev->dev,
171				       sizeof(*gpio_keys_pdata) +
172					sizeof(*gpio_keys) * n_buttons,
173				       GFP_KERNEL);
174	if (!gpio_keys_pdata)
175		return ERR_PTR(-ENOMEM);
176
177	gpio_keys = (void *)(gpio_keys_pdata + 1);
178	n_buttons = 0;
179
180	dmi_id = dmi_first_match(dmi_invalid_acpi_index);
181	if (dmi_id)
182		invalid_acpi_index = (long)dmi_id->driver_data;
183
184	for (info = button_info; info->name; info++) {
185		if (info->autorepeat != autorepeat)
186			continue;
187
188		if (info->acpi_index == invalid_acpi_index)
189			continue;
190
191		error = soc_button_lookup_gpio(&pdev->dev, info->acpi_index, &gpio, &irq);
192		if (error || irq < 0) {
193			/*
194			 * Skip GPIO if not present. Note we deliberately
195			 * ignore -EPROBE_DEFER errors here. On some devices
196			 * Intel is using so called virtual GPIOs which are not
197			 * GPIOs at all but some way for AML code to check some
198			 * random status bits without need a custom opregion.
199			 * In some cases the resources table we parse points to
200			 * such a virtual GPIO, since these are not real GPIOs
201			 * we do not have a driver for these so they will never
202			 * show up, therefore we ignore -EPROBE_DEFER.
203			 */
204			continue;
205		}
206
207		/* See dmi_use_low_level_irq[] comment */
208		if (!autorepeat && (use_low_level_irq ||
209				    dmi_check_system(dmi_use_low_level_irq))) {
210			irq_set_irq_type(irq, IRQ_TYPE_LEVEL_LOW);
211			gpio_keys[n_buttons].irq = irq;
212			gpio_keys[n_buttons].gpio = -ENOENT;
213		} else {
214			gpio_keys[n_buttons].gpio = gpio;
215		}
216
217		gpio_keys[n_buttons].type = info->event_type;
218		gpio_keys[n_buttons].code = info->event_code;
219		gpio_keys[n_buttons].active_low = info->active_low;
220		gpio_keys[n_buttons].desc = info->name;
221		gpio_keys[n_buttons].wakeup = info->wakeup;
222		/* These devices often use cheap buttons, use 50 ms debounce */
223		gpio_keys[n_buttons].debounce_interval = 50;
224		n_buttons++;
225	}
226
227	if (n_buttons == 0) {
228		error = -ENODEV;
229		goto err_free_mem;
230	}
231
232	gpio_keys_pdata->buttons = gpio_keys;
233	gpio_keys_pdata->nbuttons = n_buttons;
234	gpio_keys_pdata->rep = autorepeat;
235
236	pd = platform_device_register_resndata(&pdev->dev, "gpio-keys",
237					       PLATFORM_DEVID_AUTO, NULL, 0,
238					       gpio_keys_pdata,
239					       sizeof(*gpio_keys_pdata));
240	error = PTR_ERR_OR_ZERO(pd);
241	if (error) {
242		dev_err(&pdev->dev,
243			"failed registering gpio-keys: %d\n", error);
244		goto err_free_mem;
245	}
246
247	return pd;
248
249err_free_mem:
250	devm_kfree(&pdev->dev, gpio_keys_pdata);
251	return ERR_PTR(error);
252}
253
254static int soc_button_get_acpi_object_int(const union acpi_object *obj)
255{
256	if (obj->type != ACPI_TYPE_INTEGER)
257		return -1;
258
259	return obj->integer.value;
260}
261
262/* Parse a single ACPI0011 _DSD button descriptor */
263static int soc_button_parse_btn_desc(struct device *dev,
264				     const union acpi_object *desc,
265				     int collection_uid,
266				     struct soc_button_info *info)
267{
268	int upage, usage;
269
270	if (desc->type != ACPI_TYPE_PACKAGE ||
271	    desc->package.count != 5 ||
272	    /* First byte should be 1 (control) */
273	    soc_button_get_acpi_object_int(&desc->package.elements[0]) != 1 ||
274	    /* Third byte should be collection uid */
275	    soc_button_get_acpi_object_int(&desc->package.elements[2]) !=
276							    collection_uid) {
277		dev_err(dev, "Invalid ACPI Button Descriptor\n");
278		return -ENODEV;
279	}
280
281	info->event_type = EV_KEY;
282	info->active_low = true;
283	info->acpi_index =
284		soc_button_get_acpi_object_int(&desc->package.elements[1]);
285	upage = soc_button_get_acpi_object_int(&desc->package.elements[3]);
286	usage = soc_button_get_acpi_object_int(&desc->package.elements[4]);
287
288	/*
289	 * The UUID: fa6bd625-9ce8-470d-a2c7-b3ca36c4282e descriptors use HID
290	 * usage page and usage codes, but otherwise the device is not HID
291	 * compliant: it uses one irq per button instead of generating HID
292	 * input reports and some buttons should generate wakeups where as
293	 * others should not, so we cannot use the HID subsystem.
294	 *
295	 * Luckily all devices only use a few usage page + usage combinations,
296	 * so we can simply check for the known combinations here.
297	 */
298	if (upage == 0x01 && usage == 0x81) {
299		info->name = "power";
300		info->event_code = KEY_POWER;
301		info->wakeup = true;
302	} else if (upage == 0x01 && usage == 0xc6) {
303		info->name = "airplane mode switch";
304		info->event_type = EV_SW;
305		info->event_code = SW_RFKILL_ALL;
306		info->active_low = false;
307	} else if (upage == 0x01 && usage == 0xca) {
308		info->name = "rotation lock switch";
309		info->event_type = EV_SW;
310		info->event_code = SW_ROTATE_LOCK;
311	} else if (upage == 0x07 && usage == 0xe3) {
312		info->name = "home";
313		info->event_code = KEY_LEFTMETA;
314		info->wakeup = true;
315	} else if (upage == 0x0c && usage == 0xe9) {
316		info->name = "volume_up";
317		info->event_code = KEY_VOLUMEUP;
318		info->autorepeat = true;
319	} else if (upage == 0x0c && usage == 0xea) {
320		info->name = "volume_down";
321		info->event_code = KEY_VOLUMEDOWN;
322		info->autorepeat = true;
323	} else {
324		dev_warn(dev, "Unknown button index %d upage %02x usage %02x, ignoring\n",
325			 info->acpi_index, upage, usage);
326		info->name = "unknown";
327		info->event_code = KEY_RESERVED;
328	}
329
330	return 0;
331}
332
333/* ACPI0011 _DSD btns descriptors UUID: fa6bd625-9ce8-470d-a2c7-b3ca36c4282e */
334static const u8 btns_desc_uuid[16] = {
335	0x25, 0xd6, 0x6b, 0xfa, 0xe8, 0x9c, 0x0d, 0x47,
336	0xa2, 0xc7, 0xb3, 0xca, 0x36, 0xc4, 0x28, 0x2e
337};
338
339/* Parse ACPI0011 _DSD button descriptors */
340static struct soc_button_info *soc_button_get_button_info(struct device *dev)
341{
342	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
343	const union acpi_object *desc, *el0, *uuid, *btns_desc = NULL;
344	struct soc_button_info *button_info;
345	acpi_status status;
346	int i, btn, collection_uid = -1;
347
348	status = acpi_evaluate_object_typed(ACPI_HANDLE(dev), "_DSD", NULL,
349					    &buf, ACPI_TYPE_PACKAGE);
350	if (ACPI_FAILURE(status)) {
351		dev_err(dev, "ACPI _DSD object not found\n");
352		return ERR_PTR(-ENODEV);
353	}
354
355	/* Look for the Button Descriptors UUID */
356	desc = buf.pointer;
357	for (i = 0; (i + 1) < desc->package.count; i += 2) {
358		uuid = &desc->package.elements[i];
359
360		if (uuid->type != ACPI_TYPE_BUFFER ||
361		    uuid->buffer.length != 16 ||
362		    desc->package.elements[i + 1].type != ACPI_TYPE_PACKAGE) {
363			break;
364		}
365
366		if (memcmp(uuid->buffer.pointer, btns_desc_uuid, 16) == 0) {
367			btns_desc = &desc->package.elements[i + 1];
368			break;
369		}
370	}
371
372	if (!btns_desc) {
373		dev_err(dev, "ACPI Button Descriptors not found\n");
374		button_info = ERR_PTR(-ENODEV);
375		goto out;
376	}
377
378	/* The first package describes the collection */
379	el0 = &btns_desc->package.elements[0];
380	if (el0->type == ACPI_TYPE_PACKAGE &&
381	    el0->package.count == 5 &&
382	    /* First byte should be 0 (collection) */
383	    soc_button_get_acpi_object_int(&el0->package.elements[0]) == 0 &&
384	    /* Third byte should be 0 (top level collection) */
385	    soc_button_get_acpi_object_int(&el0->package.elements[2]) == 0) {
386		collection_uid = soc_button_get_acpi_object_int(
387						&el0->package.elements[1]);
388	}
389	if (collection_uid == -1) {
390		dev_err(dev, "Invalid Button Collection Descriptor\n");
391		button_info = ERR_PTR(-ENODEV);
392		goto out;
393	}
394
395	/* There are package.count - 1 buttons + 1 terminating empty entry */
396	button_info = devm_kcalloc(dev, btns_desc->package.count,
397				   sizeof(*button_info), GFP_KERNEL);
398	if (!button_info) {
399		button_info = ERR_PTR(-ENOMEM);
400		goto out;
401	}
402
403	/* Parse the button descriptors */
404	for (i = 1, btn = 0; i < btns_desc->package.count; i++, btn++) {
405		if (soc_button_parse_btn_desc(dev,
406					      &btns_desc->package.elements[i],
407					      collection_uid,
408					      &button_info[btn])) {
409			button_info = ERR_PTR(-ENODEV);
410			goto out;
411		}
412	}
413
414out:
415	kfree(buf.pointer);
416	return button_info;
417}
418
419static void soc_button_remove(struct platform_device *pdev)
420{
421	struct soc_button_data *priv = platform_get_drvdata(pdev);
422
423	int i;
424
425	for (i = 0; i < BUTTON_TYPES; i++)
426		if (priv->children[i])
427			platform_device_unregister(priv->children[i]);
 
 
428}
429
430static int soc_button_probe(struct platform_device *pdev)
431{
432	struct device *dev = &pdev->dev;
433	const struct soc_device_data *device_data;
434	const struct soc_button_info *button_info;
435	struct soc_button_data *priv;
436	struct platform_device *pd;
437	int i;
438	int error;
439
440	device_data = acpi_device_get_match_data(dev);
441	if (device_data && device_data->check) {
442		error = device_data->check(dev);
443		if (error)
444			return error;
445	}
446
447	if (device_data && device_data->button_info) {
448		button_info = device_data->button_info;
449	} else {
450		button_info = soc_button_get_button_info(dev);
451		if (IS_ERR(button_info))
452			return PTR_ERR(button_info);
453	}
454
455	error = gpiod_count(dev, NULL);
456	if (error < 0) {
457		dev_dbg(dev, "no GPIO attached, ignoring...\n");
458		return -ENODEV;
459	}
460
461	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
462	if (!priv)
463		return -ENOMEM;
464
465	platform_set_drvdata(pdev, priv);
466
467	for (i = 0; i < BUTTON_TYPES; i++) {
468		pd = soc_button_device_create(pdev, button_info, i == 0);
469		if (IS_ERR(pd)) {
470			error = PTR_ERR(pd);
471			if (error != -ENODEV) {
472				soc_button_remove(pdev);
473				return error;
474			}
475			continue;
476		}
477
478		priv->children[i] = pd;
479	}
480
481	if (!priv->children[0] && !priv->children[1])
482		return -ENODEV;
483
484	if (!device_data || !device_data->button_info)
485		devm_kfree(dev, button_info);
486
487	return 0;
488}
489
490/*
491 * Definition of buttons on the tablet. The ACPI index of each button
492 * is defined in section 2.8.7.2 of "Windows ACPI Design Guide for SoC
493 * Platforms"
494 */
495static const struct soc_button_info soc_button_PNP0C40[] = {
496	{ "power", 0, EV_KEY, KEY_POWER, false, true, true },
497	{ "home", 1, EV_KEY, KEY_LEFTMETA, false, true, true },
498	{ "volume_up", 2, EV_KEY, KEY_VOLUMEUP, true, false, true },
499	{ "volume_down", 3, EV_KEY, KEY_VOLUMEDOWN, true, false, true },
500	{ "rotation_lock", 4, EV_KEY, KEY_ROTATE_LOCK_TOGGLE, false, false, true },
501	{ }
502};
503
504static const struct soc_device_data soc_device_PNP0C40 = {
505	.button_info = soc_button_PNP0C40,
506};
507
508static const struct soc_button_info soc_button_INT33D3[] = {
509	{ "tablet_mode", 0, EV_SW, SW_TABLET_MODE, false, false, false },
510	{ }
511};
512
513static const struct soc_device_data soc_device_INT33D3 = {
514	.button_info = soc_button_INT33D3,
515};
516
517/*
518 * Button info for Microsoft Surface 3 (non pro), this is indentical to
519 * the PNP0C40 info except that the home button is active-high.
520 *
521 * The Surface 3 Pro also has a MSHW0028 ACPI device, but that uses a custom
522 * version of the drivers/platform/x86/intel/hid.c 5 button array ACPI API
523 * instead. A check() callback is not necessary though as the Surface 3 Pro
524 * MSHW0028 ACPI device's resource table does not contain any GPIOs.
525 */
526static const struct soc_button_info soc_button_MSHW0028[] = {
527	{ "power", 0, EV_KEY, KEY_POWER, false, true, true },
528	{ "home", 1, EV_KEY, KEY_LEFTMETA, false, true, false },
529	{ "volume_up", 2, EV_KEY, KEY_VOLUMEUP, true, false, true },
530	{ "volume_down", 3, EV_KEY, KEY_VOLUMEDOWN, true, false, true },
531	{ }
532};
533
534static const struct soc_device_data soc_device_MSHW0028 = {
535	.button_info = soc_button_MSHW0028,
536};
537
538/*
539 * Special device check for Surface Book 2 and Surface Pro (2017).
540 * Both, the Surface Pro 4 (surfacepro3_button.c) and the above mentioned
541 * devices use MSHW0040 for power and volume buttons, however the way they
542 * have to be addressed differs. Make sure that we only load this drivers
543 * for the correct devices by checking the OEM Platform Revision provided by
544 * the _DSM method.
545 */
546#define MSHW0040_DSM_REVISION		0x01
547#define MSHW0040_DSM_GET_OMPR		0x02	// get OEM Platform Revision
548static const guid_t MSHW0040_DSM_UUID =
549	GUID_INIT(0x6fd05c69, 0xcde3, 0x49f4, 0x95, 0xed, 0xab, 0x16, 0x65,
550		  0x49, 0x80, 0x35);
551
552static int soc_device_check_MSHW0040(struct device *dev)
553{
554	acpi_handle handle = ACPI_HANDLE(dev);
555	union acpi_object *result;
556	u64 oem_platform_rev = 0;	// valid revisions are nonzero
557
558	// get OEM platform revision
559	result = acpi_evaluate_dsm_typed(handle, &MSHW0040_DSM_UUID,
560					 MSHW0040_DSM_REVISION,
561					 MSHW0040_DSM_GET_OMPR, NULL,
562					 ACPI_TYPE_INTEGER);
563
564	if (result) {
565		oem_platform_rev = result->integer.value;
566		ACPI_FREE(result);
567	}
568
569	/*
570	 * If the revision is zero here, the _DSM evaluation has failed. This
571	 * indicates that we have a Pro 4 or Book 1 and this driver should not
572	 * be used.
573	 */
574	if (oem_platform_rev == 0)
575		return -ENODEV;
576
577	dev_dbg(dev, "OEM Platform Revision %llu\n", oem_platform_rev);
578
579	return 0;
580}
581
582/*
583 * Button infos for Microsoft Surface Book 2 and Surface Pro (2017).
584 * Obtained from DSDT/testing.
585 */
586static const struct soc_button_info soc_button_MSHW0040[] = {
587	{ "power", 0, EV_KEY, KEY_POWER, false, true, true },
588	{ "volume_up", 2, EV_KEY, KEY_VOLUMEUP, true, false, true },
589	{ "volume_down", 4, EV_KEY, KEY_VOLUMEDOWN, true, false, true },
590	{ }
591};
592
593static const struct soc_device_data soc_device_MSHW0040 = {
594	.button_info = soc_button_MSHW0040,
595	.check = soc_device_check_MSHW0040,
596};
597
598static const struct acpi_device_id soc_button_acpi_match[] = {
599	{ "PNP0C40", (unsigned long)&soc_device_PNP0C40 },
600	{ "INT33D3", (unsigned long)&soc_device_INT33D3 },
601	{ "ID9001", (unsigned long)&soc_device_INT33D3 },
602	{ "ACPI0011", 0 },
603
604	/* Microsoft Surface Devices (3th, 5th and 6th generation) */
605	{ "MSHW0028", (unsigned long)&soc_device_MSHW0028 },
606	{ "MSHW0040", (unsigned long)&soc_device_MSHW0040 },
607
608	{ }
609};
610
611MODULE_DEVICE_TABLE(acpi, soc_button_acpi_match);
612
613static struct platform_driver soc_button_driver = {
614	.probe          = soc_button_probe,
615	.remove_new	= soc_button_remove,
616	.driver		= {
617		.name = KBUILD_MODNAME,
618		.acpi_match_table = ACPI_PTR(soc_button_acpi_match),
619	},
620};
621module_platform_driver(soc_button_driver);
622
623MODULE_LICENSE("GPL");
v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Supports for the button array on SoC tablets originally running
  4 * Windows 8.
  5 *
  6 * (C) Copyright 2014 Intel Corporation
  7 */
  8
  9#include <linux/module.h>
 10#include <linux/input.h>
 11#include <linux/init.h>
 12#include <linux/irq.h>
 13#include <linux/kernel.h>
 14#include <linux/acpi.h>
 15#include <linux/dmi.h>
 16#include <linux/gpio/consumer.h>
 17#include <linux/gpio_keys.h>
 18#include <linux/gpio.h>
 19#include <linux/platform_device.h>
 20
 21static bool use_low_level_irq;
 22module_param(use_low_level_irq, bool, 0444);
 23MODULE_PARM_DESC(use_low_level_irq, "Use low-level triggered IRQ instead of edge triggered");
 24
 25struct soc_button_info {
 26	const char *name;
 27	int acpi_index;
 28	unsigned int event_type;
 29	unsigned int event_code;
 30	bool autorepeat;
 31	bool wakeup;
 32	bool active_low;
 33};
 34
 35struct soc_device_data {
 36	const struct soc_button_info *button_info;
 37	int (*check)(struct device *dev);
 38};
 39
 40/*
 41 * Some of the buttons like volume up/down are auto repeat, while others
 42 * are not. To support both, we register two platform devices, and put
 43 * buttons into them based on whether the key should be auto repeat.
 44 */
 45#define BUTTON_TYPES	2
 46
 47struct soc_button_data {
 48	struct platform_device *children[BUTTON_TYPES];
 49};
 50
 51/*
 52 * Some 2-in-1s which use the soc_button_array driver have this ugly issue in
 53 * their DSDT where the _LID method modifies the irq-type settings of the GPIOs
 54 * used for the power and home buttons. The intend of this AML code is to
 55 * disable these buttons when the lid is closed.
 56 * The AML does this by directly poking the GPIO controllers registers. This is
 57 * problematic because when re-enabling the irq, which happens whenever _LID
 58 * gets called with the lid open (e.g. on boot and on resume), it sets the
 59 * irq-type to IRQ_TYPE_LEVEL_LOW. Where as the gpio-keys driver programs the
 60 * type to, and expects it to be, IRQ_TYPE_EDGE_BOTH.
 61 * To work around this we don't set gpio_keys_button.gpio on these 2-in-1s,
 62 * instead we get the irq for the GPIO ourselves, configure it as
 63 * IRQ_TYPE_LEVEL_LOW (to match how the _LID AML code configures it) and pass
 64 * the irq in gpio_keys_button.irq. Below is a list of affected devices.
 65 */
 66static const struct dmi_system_id dmi_use_low_level_irq[] = {
 67	{
 68		/*
 69		 * Acer Switch 10 SW5-012. _LID method messes with home- and
 70		 * power-button GPIO IRQ settings. When (re-)enabling the irq
 71		 * it ors in its own flags without clearing the previous set
 72		 * ones, leading to an irq-type of IRQ_TYPE_LEVEL_LOW |
 73		 * IRQ_TYPE_LEVEL_HIGH causing a continuous interrupt storm.
 74		 */
 75		.matches = {
 76			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 77			DMI_MATCH(DMI_PRODUCT_NAME, "Aspire SW5-012"),
 78		},
 79	},
 80	{
 81		/* Acer Switch V 10 SW5-017, same issue as Acer Switch 10 SW5-012. */
 82		.matches = {
 83			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 84			DMI_MATCH(DMI_PRODUCT_NAME, "SW5-017"),
 85		},
 86	},
 87	{
 88		/*
 89		 * Acer One S1003. _LID method messes with power-button GPIO
 90		 * IRQ settings, leading to a non working power-button.
 91		 */
 92		.matches = {
 93			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 94			DMI_MATCH(DMI_PRODUCT_NAME, "One S1003"),
 95		},
 96	},
 97	{
 98		/*
 99		 * Lenovo Yoga Tab2 1051F/1051L, something messes with the home-button
100		 * IRQ settings, leading to a non working home-button.
101		 */
102		.matches = {
103			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
104			DMI_MATCH(DMI_PRODUCT_NAME, "60073"),
105			DMI_MATCH(DMI_PRODUCT_VERSION, "1051"),
106		},
107	},
108	{} /* Terminating entry */
109};
110
111/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
112 * Get the Nth GPIO number from the ACPI object.
113 */
114static int soc_button_lookup_gpio(struct device *dev, int acpi_index,
115				  int *gpio_ret, int *irq_ret)
116{
117	struct gpio_desc *desc;
118
119	desc = gpiod_get_index(dev, NULL, acpi_index, GPIOD_ASIS);
120	if (IS_ERR(desc))
121		return PTR_ERR(desc);
122
123	*gpio_ret = desc_to_gpio(desc);
124	*irq_ret = gpiod_to_irq(desc);
125
126	gpiod_put(desc);
127
128	return 0;
129}
130
131static struct platform_device *
132soc_button_device_create(struct platform_device *pdev,
133			 const struct soc_button_info *button_info,
134			 bool autorepeat)
135{
136	const struct soc_button_info *info;
137	struct platform_device *pd;
138	struct gpio_keys_button *gpio_keys;
139	struct gpio_keys_platform_data *gpio_keys_pdata;
 
 
140	int error, gpio, irq;
141	int n_buttons = 0;
142
143	for (info = button_info; info->name; info++)
144		if (info->autorepeat == autorepeat)
145			n_buttons++;
146
147	gpio_keys_pdata = devm_kzalloc(&pdev->dev,
148				       sizeof(*gpio_keys_pdata) +
149					sizeof(*gpio_keys) * n_buttons,
150				       GFP_KERNEL);
151	if (!gpio_keys_pdata)
152		return ERR_PTR(-ENOMEM);
153
154	gpio_keys = (void *)(gpio_keys_pdata + 1);
155	n_buttons = 0;
156
 
 
 
 
157	for (info = button_info; info->name; info++) {
158		if (info->autorepeat != autorepeat)
159			continue;
160
 
 
 
161		error = soc_button_lookup_gpio(&pdev->dev, info->acpi_index, &gpio, &irq);
162		if (error || irq < 0) {
163			/*
164			 * Skip GPIO if not present. Note we deliberately
165			 * ignore -EPROBE_DEFER errors here. On some devices
166			 * Intel is using so called virtual GPIOs which are not
167			 * GPIOs at all but some way for AML code to check some
168			 * random status bits without need a custom opregion.
169			 * In some cases the resources table we parse points to
170			 * such a virtual GPIO, since these are not real GPIOs
171			 * we do not have a driver for these so they will never
172			 * show up, therefore we ignore -EPROBE_DEFER.
173			 */
174			continue;
175		}
176
177		/* See dmi_use_low_level_irq[] comment */
178		if (!autorepeat && (use_low_level_irq ||
179				    dmi_check_system(dmi_use_low_level_irq))) {
180			irq_set_irq_type(irq, IRQ_TYPE_LEVEL_LOW);
181			gpio_keys[n_buttons].irq = irq;
182			gpio_keys[n_buttons].gpio = -ENOENT;
183		} else {
184			gpio_keys[n_buttons].gpio = gpio;
185		}
186
187		gpio_keys[n_buttons].type = info->event_type;
188		gpio_keys[n_buttons].code = info->event_code;
189		gpio_keys[n_buttons].active_low = info->active_low;
190		gpio_keys[n_buttons].desc = info->name;
191		gpio_keys[n_buttons].wakeup = info->wakeup;
192		/* These devices often use cheap buttons, use 50 ms debounce */
193		gpio_keys[n_buttons].debounce_interval = 50;
194		n_buttons++;
195	}
196
197	if (n_buttons == 0) {
198		error = -ENODEV;
199		goto err_free_mem;
200	}
201
202	gpio_keys_pdata->buttons = gpio_keys;
203	gpio_keys_pdata->nbuttons = n_buttons;
204	gpio_keys_pdata->rep = autorepeat;
205
206	pd = platform_device_register_resndata(&pdev->dev, "gpio-keys",
207					       PLATFORM_DEVID_AUTO, NULL, 0,
208					       gpio_keys_pdata,
209					       sizeof(*gpio_keys_pdata));
210	error = PTR_ERR_OR_ZERO(pd);
211	if (error) {
212		dev_err(&pdev->dev,
213			"failed registering gpio-keys: %d\n", error);
214		goto err_free_mem;
215	}
216
217	return pd;
218
219err_free_mem:
220	devm_kfree(&pdev->dev, gpio_keys_pdata);
221	return ERR_PTR(error);
222}
223
224static int soc_button_get_acpi_object_int(const union acpi_object *obj)
225{
226	if (obj->type != ACPI_TYPE_INTEGER)
227		return -1;
228
229	return obj->integer.value;
230}
231
232/* Parse a single ACPI0011 _DSD button descriptor */
233static int soc_button_parse_btn_desc(struct device *dev,
234				     const union acpi_object *desc,
235				     int collection_uid,
236				     struct soc_button_info *info)
237{
238	int upage, usage;
239
240	if (desc->type != ACPI_TYPE_PACKAGE ||
241	    desc->package.count != 5 ||
242	    /* First byte should be 1 (control) */
243	    soc_button_get_acpi_object_int(&desc->package.elements[0]) != 1 ||
244	    /* Third byte should be collection uid */
245	    soc_button_get_acpi_object_int(&desc->package.elements[2]) !=
246							    collection_uid) {
247		dev_err(dev, "Invalid ACPI Button Descriptor\n");
248		return -ENODEV;
249	}
250
251	info->event_type = EV_KEY;
252	info->active_low = true;
253	info->acpi_index =
254		soc_button_get_acpi_object_int(&desc->package.elements[1]);
255	upage = soc_button_get_acpi_object_int(&desc->package.elements[3]);
256	usage = soc_button_get_acpi_object_int(&desc->package.elements[4]);
257
258	/*
259	 * The UUID: fa6bd625-9ce8-470d-a2c7-b3ca36c4282e descriptors use HID
260	 * usage page and usage codes, but otherwise the device is not HID
261	 * compliant: it uses one irq per button instead of generating HID
262	 * input reports and some buttons should generate wakeups where as
263	 * others should not, so we cannot use the HID subsystem.
264	 *
265	 * Luckily all devices only use a few usage page + usage combinations,
266	 * so we can simply check for the known combinations here.
267	 */
268	if (upage == 0x01 && usage == 0x81) {
269		info->name = "power";
270		info->event_code = KEY_POWER;
271		info->wakeup = true;
 
 
 
 
 
272	} else if (upage == 0x01 && usage == 0xca) {
273		info->name = "rotation lock switch";
274		info->event_type = EV_SW;
275		info->event_code = SW_ROTATE_LOCK;
276	} else if (upage == 0x07 && usage == 0xe3) {
277		info->name = "home";
278		info->event_code = KEY_LEFTMETA;
279		info->wakeup = true;
280	} else if (upage == 0x0c && usage == 0xe9) {
281		info->name = "volume_up";
282		info->event_code = KEY_VOLUMEUP;
283		info->autorepeat = true;
284	} else if (upage == 0x0c && usage == 0xea) {
285		info->name = "volume_down";
286		info->event_code = KEY_VOLUMEDOWN;
287		info->autorepeat = true;
288	} else {
289		dev_warn(dev, "Unknown button index %d upage %02x usage %02x, ignoring\n",
290			 info->acpi_index, upage, usage);
291		info->name = "unknown";
292		info->event_code = KEY_RESERVED;
293	}
294
295	return 0;
296}
297
298/* ACPI0011 _DSD btns descriptors UUID: fa6bd625-9ce8-470d-a2c7-b3ca36c4282e */
299static const u8 btns_desc_uuid[16] = {
300	0x25, 0xd6, 0x6b, 0xfa, 0xe8, 0x9c, 0x0d, 0x47,
301	0xa2, 0xc7, 0xb3, 0xca, 0x36, 0xc4, 0x28, 0x2e
302};
303
304/* Parse ACPI0011 _DSD button descriptors */
305static struct soc_button_info *soc_button_get_button_info(struct device *dev)
306{
307	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
308	const union acpi_object *desc, *el0, *uuid, *btns_desc = NULL;
309	struct soc_button_info *button_info;
310	acpi_status status;
311	int i, btn, collection_uid = -1;
312
313	status = acpi_evaluate_object_typed(ACPI_HANDLE(dev), "_DSD", NULL,
314					    &buf, ACPI_TYPE_PACKAGE);
315	if (ACPI_FAILURE(status)) {
316		dev_err(dev, "ACPI _DSD object not found\n");
317		return ERR_PTR(-ENODEV);
318	}
319
320	/* Look for the Button Descriptors UUID */
321	desc = buf.pointer;
322	for (i = 0; (i + 1) < desc->package.count; i += 2) {
323		uuid = &desc->package.elements[i];
324
325		if (uuid->type != ACPI_TYPE_BUFFER ||
326		    uuid->buffer.length != 16 ||
327		    desc->package.elements[i + 1].type != ACPI_TYPE_PACKAGE) {
328			break;
329		}
330
331		if (memcmp(uuid->buffer.pointer, btns_desc_uuid, 16) == 0) {
332			btns_desc = &desc->package.elements[i + 1];
333			break;
334		}
335	}
336
337	if (!btns_desc) {
338		dev_err(dev, "ACPI Button Descriptors not found\n");
339		button_info = ERR_PTR(-ENODEV);
340		goto out;
341	}
342
343	/* The first package describes the collection */
344	el0 = &btns_desc->package.elements[0];
345	if (el0->type == ACPI_TYPE_PACKAGE &&
346	    el0->package.count == 5 &&
347	    /* First byte should be 0 (collection) */
348	    soc_button_get_acpi_object_int(&el0->package.elements[0]) == 0 &&
349	    /* Third byte should be 0 (top level collection) */
350	    soc_button_get_acpi_object_int(&el0->package.elements[2]) == 0) {
351		collection_uid = soc_button_get_acpi_object_int(
352						&el0->package.elements[1]);
353	}
354	if (collection_uid == -1) {
355		dev_err(dev, "Invalid Button Collection Descriptor\n");
356		button_info = ERR_PTR(-ENODEV);
357		goto out;
358	}
359
360	/* There are package.count - 1 buttons + 1 terminating empty entry */
361	button_info = devm_kcalloc(dev, btns_desc->package.count,
362				   sizeof(*button_info), GFP_KERNEL);
363	if (!button_info) {
364		button_info = ERR_PTR(-ENOMEM);
365		goto out;
366	}
367
368	/* Parse the button descriptors */
369	for (i = 1, btn = 0; i < btns_desc->package.count; i++, btn++) {
370		if (soc_button_parse_btn_desc(dev,
371					      &btns_desc->package.elements[i],
372					      collection_uid,
373					      &button_info[btn])) {
374			button_info = ERR_PTR(-ENODEV);
375			goto out;
376		}
377	}
378
379out:
380	kfree(buf.pointer);
381	return button_info;
382}
383
384static int soc_button_remove(struct platform_device *pdev)
385{
386	struct soc_button_data *priv = platform_get_drvdata(pdev);
387
388	int i;
389
390	for (i = 0; i < BUTTON_TYPES; i++)
391		if (priv->children[i])
392			platform_device_unregister(priv->children[i]);
393
394	return 0;
395}
396
397static int soc_button_probe(struct platform_device *pdev)
398{
399	struct device *dev = &pdev->dev;
400	const struct soc_device_data *device_data;
401	const struct soc_button_info *button_info;
402	struct soc_button_data *priv;
403	struct platform_device *pd;
404	int i;
405	int error;
406
407	device_data = acpi_device_get_match_data(dev);
408	if (device_data && device_data->check) {
409		error = device_data->check(dev);
410		if (error)
411			return error;
412	}
413
414	if (device_data && device_data->button_info) {
415		button_info = device_data->button_info;
416	} else {
417		button_info = soc_button_get_button_info(dev);
418		if (IS_ERR(button_info))
419			return PTR_ERR(button_info);
420	}
421
422	error = gpiod_count(dev, NULL);
423	if (error < 0) {
424		dev_dbg(dev, "no GPIO attached, ignoring...\n");
425		return -ENODEV;
426	}
427
428	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
429	if (!priv)
430		return -ENOMEM;
431
432	platform_set_drvdata(pdev, priv);
433
434	for (i = 0; i < BUTTON_TYPES; i++) {
435		pd = soc_button_device_create(pdev, button_info, i == 0);
436		if (IS_ERR(pd)) {
437			error = PTR_ERR(pd);
438			if (error != -ENODEV) {
439				soc_button_remove(pdev);
440				return error;
441			}
442			continue;
443		}
444
445		priv->children[i] = pd;
446	}
447
448	if (!priv->children[0] && !priv->children[1])
449		return -ENODEV;
450
451	if (!device_data || !device_data->button_info)
452		devm_kfree(dev, button_info);
453
454	return 0;
455}
456
457/*
458 * Definition of buttons on the tablet. The ACPI index of each button
459 * is defined in section 2.8.7.2 of "Windows ACPI Design Guide for SoC
460 * Platforms"
461 */
462static const struct soc_button_info soc_button_PNP0C40[] = {
463	{ "power", 0, EV_KEY, KEY_POWER, false, true, true },
464	{ "home", 1, EV_KEY, KEY_LEFTMETA, false, true, true },
465	{ "volume_up", 2, EV_KEY, KEY_VOLUMEUP, true, false, true },
466	{ "volume_down", 3, EV_KEY, KEY_VOLUMEDOWN, true, false, true },
467	{ "rotation_lock", 4, EV_KEY, KEY_ROTATE_LOCK_TOGGLE, false, false, true },
468	{ }
469};
470
471static const struct soc_device_data soc_device_PNP0C40 = {
472	.button_info = soc_button_PNP0C40,
473};
474
475static const struct soc_button_info soc_button_INT33D3[] = {
476	{ "tablet_mode", 0, EV_SW, SW_TABLET_MODE, false, false, false },
477	{ }
478};
479
480static const struct soc_device_data soc_device_INT33D3 = {
481	.button_info = soc_button_INT33D3,
482};
483
484/*
485 * Button info for Microsoft Surface 3 (non pro), this is indentical to
486 * the PNP0C40 info except that the home button is active-high.
487 *
488 * The Surface 3 Pro also has a MSHW0028 ACPI device, but that uses a custom
489 * version of the drivers/platform/x86/intel/hid.c 5 button array ACPI API
490 * instead. A check() callback is not necessary though as the Surface 3 Pro
491 * MSHW0028 ACPI device's resource table does not contain any GPIOs.
492 */
493static const struct soc_button_info soc_button_MSHW0028[] = {
494	{ "power", 0, EV_KEY, KEY_POWER, false, true, true },
495	{ "home", 1, EV_KEY, KEY_LEFTMETA, false, true, false },
496	{ "volume_up", 2, EV_KEY, KEY_VOLUMEUP, true, false, true },
497	{ "volume_down", 3, EV_KEY, KEY_VOLUMEDOWN, true, false, true },
498	{ }
499};
500
501static const struct soc_device_data soc_device_MSHW0028 = {
502	.button_info = soc_button_MSHW0028,
503};
504
505/*
506 * Special device check for Surface Book 2 and Surface Pro (2017).
507 * Both, the Surface Pro 4 (surfacepro3_button.c) and the above mentioned
508 * devices use MSHW0040 for power and volume buttons, however the way they
509 * have to be addressed differs. Make sure that we only load this drivers
510 * for the correct devices by checking the OEM Platform Revision provided by
511 * the _DSM method.
512 */
513#define MSHW0040_DSM_REVISION		0x01
514#define MSHW0040_DSM_GET_OMPR		0x02	// get OEM Platform Revision
515static const guid_t MSHW0040_DSM_UUID =
516	GUID_INIT(0x6fd05c69, 0xcde3, 0x49f4, 0x95, 0xed, 0xab, 0x16, 0x65,
517		  0x49, 0x80, 0x35);
518
519static int soc_device_check_MSHW0040(struct device *dev)
520{
521	acpi_handle handle = ACPI_HANDLE(dev);
522	union acpi_object *result;
523	u64 oem_platform_rev = 0;	// valid revisions are nonzero
524
525	// get OEM platform revision
526	result = acpi_evaluate_dsm_typed(handle, &MSHW0040_DSM_UUID,
527					 MSHW0040_DSM_REVISION,
528					 MSHW0040_DSM_GET_OMPR, NULL,
529					 ACPI_TYPE_INTEGER);
530
531	if (result) {
532		oem_platform_rev = result->integer.value;
533		ACPI_FREE(result);
534	}
535
536	/*
537	 * If the revision is zero here, the _DSM evaluation has failed. This
538	 * indicates that we have a Pro 4 or Book 1 and this driver should not
539	 * be used.
540	 */
541	if (oem_platform_rev == 0)
542		return -ENODEV;
543
544	dev_dbg(dev, "OEM Platform Revision %llu\n", oem_platform_rev);
545
546	return 0;
547}
548
549/*
550 * Button infos for Microsoft Surface Book 2 and Surface Pro (2017).
551 * Obtained from DSDT/testing.
552 */
553static const struct soc_button_info soc_button_MSHW0040[] = {
554	{ "power", 0, EV_KEY, KEY_POWER, false, true, true },
555	{ "volume_up", 2, EV_KEY, KEY_VOLUMEUP, true, false, true },
556	{ "volume_down", 4, EV_KEY, KEY_VOLUMEDOWN, true, false, true },
557	{ }
558};
559
560static const struct soc_device_data soc_device_MSHW0040 = {
561	.button_info = soc_button_MSHW0040,
562	.check = soc_device_check_MSHW0040,
563};
564
565static const struct acpi_device_id soc_button_acpi_match[] = {
566	{ "PNP0C40", (unsigned long)&soc_device_PNP0C40 },
567	{ "INT33D3", (unsigned long)&soc_device_INT33D3 },
568	{ "ID9001", (unsigned long)&soc_device_INT33D3 },
569	{ "ACPI0011", 0 },
570
571	/* Microsoft Surface Devices (3th, 5th and 6th generation) */
572	{ "MSHW0028", (unsigned long)&soc_device_MSHW0028 },
573	{ "MSHW0040", (unsigned long)&soc_device_MSHW0040 },
574
575	{ }
576};
577
578MODULE_DEVICE_TABLE(acpi, soc_button_acpi_match);
579
580static struct platform_driver soc_button_driver = {
581	.probe          = soc_button_probe,
582	.remove		= soc_button_remove,
583	.driver		= {
584		.name = KBUILD_MODNAME,
585		.acpi_match_table = ACPI_PTR(soc_button_acpi_match),
586	},
587};
588module_platform_driver(soc_button_driver);
589
590MODULE_LICENSE("GPL");