1 // SPDX-License-Identifier: GPL-2.0-only
3 * Supports for the button array on SoC tablets originally running
6 * (C) Copyright 2014 Intel Corporation
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>
21 static bool use_low_level_irq;
22 module_param(use_low_level_irq, bool, 0444);
23 MODULE_PARM_DESC(use_low_level_irq, "Use low-level triggered IRQ instead of edge triggered");
25 struct soc_button_info {
28 unsigned int event_type;
29 unsigned int event_code;
35 struct soc_device_data {
36 const struct soc_button_info *button_info;
37 int (*check)(struct device *dev);
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.
45 #define BUTTON_TYPES 2
47 struct soc_button_data {
48 struct platform_device *children[BUTTON_TYPES];
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.
66 static const struct dmi_system_id dmi_use_low_level_irq[] = {
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.
76 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
77 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire SW5-012"),
81 /* Acer Switch V 10 SW5-017, same issue as Acer Switch 10 SW5-012. */
83 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
84 DMI_MATCH(DMI_PRODUCT_NAME, "SW5-017"),
89 * Acer One S1003. _LID method messes with power-button GPIO
90 * IRQ settings, leading to a non working power-button.
93 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
94 DMI_MATCH(DMI_PRODUCT_NAME, "One S1003"),
99 * Lenovo Yoga Tab2 1051F/1051L, something messes with the home-button
100 * IRQ settings, leading to a non working home-button.
103 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
104 DMI_MATCH(DMI_PRODUCT_NAME, "60073"),
105 DMI_MATCH(DMI_PRODUCT_VERSION, "1051"),
108 {} /* Terminating entry */
112 * Get the Nth GPIO number from the ACPI object.
114 static int soc_button_lookup_gpio(struct device *dev, int acpi_index,
115 int *gpio_ret, int *irq_ret)
117 struct gpio_desc *desc;
119 desc = gpiod_get_index(dev, NULL, acpi_index, GPIOD_ASIS);
121 return PTR_ERR(desc);
123 *gpio_ret = desc_to_gpio(desc);
124 *irq_ret = gpiod_to_irq(desc);
131 static struct platform_device *
132 soc_button_device_create(struct platform_device *pdev,
133 const struct soc_button_info *button_info,
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;
143 for (info = button_info; info->name; info++)
144 if (info->autorepeat == autorepeat)
147 gpio_keys_pdata = devm_kzalloc(&pdev->dev,
148 sizeof(*gpio_keys_pdata) +
149 sizeof(*gpio_keys) * n_buttons,
151 if (!gpio_keys_pdata)
152 return ERR_PTR(-ENOMEM);
154 gpio_keys = (void *)(gpio_keys_pdata + 1);
157 for (info = button_info; info->name; info++) {
158 if (info->autorepeat != autorepeat)
161 error = soc_button_lookup_gpio(&pdev->dev, info->acpi_index, &gpio, &irq);
162 if (error || irq < 0) {
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.
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;
184 gpio_keys[n_buttons].gpio = gpio;
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;
197 if (n_buttons == 0) {
202 gpio_keys_pdata->buttons = gpio_keys;
203 gpio_keys_pdata->nbuttons = n_buttons;
204 gpio_keys_pdata->rep = autorepeat;
206 pd = platform_device_register_resndata(&pdev->dev, "gpio-keys",
207 PLATFORM_DEVID_AUTO, NULL, 0,
209 sizeof(*gpio_keys_pdata));
210 error = PTR_ERR_OR_ZERO(pd);
213 "failed registering gpio-keys: %d\n", error);
220 devm_kfree(&pdev->dev, gpio_keys_pdata);
221 return ERR_PTR(error);
224 static int soc_button_get_acpi_object_int(const union acpi_object *obj)
226 if (obj->type != ACPI_TYPE_INTEGER)
229 return obj->integer.value;
232 /* Parse a single ACPI0011 _DSD button descriptor */
233 static int soc_button_parse_btn_desc(struct device *dev,
234 const union acpi_object *desc,
236 struct soc_button_info *info)
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]) !=
247 dev_err(dev, "Invalid ACPI Button Descriptor\n");
251 info->event_type = EV_KEY;
252 info->active_low = true;
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]);
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.
265 * Luckily all devices only use a few usage page + usage combinations,
266 * so we can simply check for the known combinations here.
268 if (upage == 0x01 && usage == 0x81) {
269 info->name = "power";
270 info->event_code = KEY_POWER;
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) {
278 info->event_code = KEY_LEFTMETA;
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;
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;
298 /* ACPI0011 _DSD btns descriptors UUID: fa6bd625-9ce8-470d-a2c7-b3ca36c4282e */
299 static const u8 btns_desc_uuid[16] = {
300 0x25, 0xd6, 0x6b, 0xfa, 0xe8, 0x9c, 0x0d, 0x47,
301 0xa2, 0xc7, 0xb3, 0xca, 0x36, 0xc4, 0x28, 0x2e
304 /* Parse ACPI0011 _DSD button descriptors */
305 static struct soc_button_info *soc_button_get_button_info(struct device *dev)
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;
311 int i, btn, collection_uid = -1;
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);
320 /* Look for the Button Descriptors UUID */
322 for (i = 0; (i + 1) < desc->package.count; i += 2) {
323 uuid = &desc->package.elements[i];
325 if (uuid->type != ACPI_TYPE_BUFFER ||
326 uuid->buffer.length != 16 ||
327 desc->package.elements[i + 1].type != ACPI_TYPE_PACKAGE) {
331 if (memcmp(uuid->buffer.pointer, btns_desc_uuid, 16) == 0) {
332 btns_desc = &desc->package.elements[i + 1];
338 dev_err(dev, "ACPI Button Descriptors not found\n");
339 button_info = ERR_PTR(-ENODEV);
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]);
354 if (collection_uid == -1) {
355 dev_err(dev, "Invalid Button Collection Descriptor\n");
356 button_info = ERR_PTR(-ENODEV);
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);
364 button_info = ERR_PTR(-ENOMEM);
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],
373 &button_info[btn])) {
374 button_info = ERR_PTR(-ENODEV);
384 static int soc_button_remove(struct platform_device *pdev)
386 struct soc_button_data *priv = platform_get_drvdata(pdev);
390 for (i = 0; i < BUTTON_TYPES; i++)
391 if (priv->children[i])
392 platform_device_unregister(priv->children[i]);
397 static int soc_button_probe(struct platform_device *pdev)
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;
407 device_data = acpi_device_get_match_data(dev);
408 if (device_data && device_data->check) {
409 error = device_data->check(dev);
414 if (device_data && device_data->button_info) {
415 button_info = device_data->button_info;
417 button_info = soc_button_get_button_info(dev);
418 if (IS_ERR(button_info))
419 return PTR_ERR(button_info);
422 error = gpiod_count(dev, NULL);
424 dev_dbg(dev, "no GPIO attached, ignoring...\n");
428 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
432 platform_set_drvdata(pdev, priv);
434 for (i = 0; i < BUTTON_TYPES; i++) {
435 pd = soc_button_device_create(pdev, button_info, i == 0);
438 if (error != -ENODEV) {
439 soc_button_remove(pdev);
445 priv->children[i] = pd;
448 if (!priv->children[0] && !priv->children[1])
451 if (!device_data || !device_data->button_info)
452 devm_kfree(dev, button_info);
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
462 static 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 },
471 static const struct soc_device_data soc_device_PNP0C40 = {
472 .button_info = soc_button_PNP0C40,
475 static const struct soc_button_info soc_button_INT33D3[] = {
476 { "tablet_mode", 0, EV_SW, SW_TABLET_MODE, false, false, false },
480 static const struct soc_device_data soc_device_INT33D3 = {
481 .button_info = soc_button_INT33D3,
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.
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.
493 static 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 },
501 static const struct soc_device_data soc_device_MSHW0028 = {
502 .button_info = soc_button_MSHW0028,
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
513 #define MSHW0040_DSM_REVISION 0x01
514 #define MSHW0040_DSM_GET_OMPR 0x02 // get OEM Platform Revision
515 static const guid_t MSHW0040_DSM_UUID =
516 GUID_INIT(0x6fd05c69, 0xcde3, 0x49f4, 0x95, 0xed, 0xab, 0x16, 0x65,
519 static int soc_device_check_MSHW0040(struct device *dev)
521 acpi_handle handle = ACPI_HANDLE(dev);
522 union acpi_object *result;
523 u64 oem_platform_rev = 0; // valid revisions are nonzero
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,
532 oem_platform_rev = result->integer.value;
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
541 if (oem_platform_rev == 0)
544 dev_dbg(dev, "OEM Platform Revision %llu\n", oem_platform_rev);
550 * Button infos for Microsoft Surface Book 2 and Surface Pro (2017).
551 * Obtained from DSDT/testing.
553 static 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 },
560 static const struct soc_device_data soc_device_MSHW0040 = {
561 .button_info = soc_button_MSHW0040,
562 .check = soc_device_check_MSHW0040,
565 static 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 },
571 /* Microsoft Surface Devices (3th, 5th and 6th generation) */
572 { "MSHW0028", (unsigned long)&soc_device_MSHW0028 },
573 { "MSHW0040", (unsigned long)&soc_device_MSHW0040 },
578 MODULE_DEVICE_TABLE(acpi, soc_button_acpi_match);
580 static struct platform_driver soc_button_driver = {
581 .probe = soc_button_probe,
582 .remove = soc_button_remove,
584 .name = KBUILD_MODNAME,
585 .acpi_match_table = ACPI_PTR(soc_button_acpi_match),
588 module_platform_driver(soc_button_driver);
590 MODULE_LICENSE("GPL");