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
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");
24
25 struct 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
35 struct 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
47 struct 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 */
66 static 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 */
115 static 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 */
soc_button_lookup_gpio(struct device * dev,int acpi_index,int * gpio_ret,int * irq_ret)135 static 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
152 static struct platform_device *
soc_button_device_create(struct platform_device * pdev,const struct soc_button_info * button_info,bool autorepeat)153 soc_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
249 err_free_mem:
250 devm_kfree(&pdev->dev, gpio_keys_pdata);
251 return ERR_PTR(error);
252 }
253
soc_button_get_acpi_object_int(const union acpi_object * obj)254 static 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 */
soc_button_parse_btn_desc(struct device * dev,const union acpi_object * desc,int collection_uid,struct soc_button_info * info)263 static 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 */
334 static 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 */
soc_button_get_button_info(struct device * dev)340 static 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
414 out:
415 kfree(buf.pointer);
416 return button_info;
417 }
418
soc_button_remove(struct platform_device * pdev)419 static 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
soc_button_probe(struct platform_device * pdev)430 static 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 */
495 static 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
504 static const struct soc_device_data soc_device_PNP0C40 = {
505 .button_info = soc_button_PNP0C40,
506 };
507
508 static const struct soc_button_info soc_button_INT33D3[] = {
509 { "tablet_mode", 0, EV_SW, SW_TABLET_MODE, false, false, false },
510 { }
511 };
512
513 static 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 */
526 static 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
534 static 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
548 static const guid_t MSHW0040_DSM_UUID =
549 GUID_INIT(0x6fd05c69, 0xcde3, 0x49f4, 0x95, 0xed, 0xab, 0x16, 0x65,
550 0x49, 0x80, 0x35);
551
soc_device_check_MSHW0040(struct device * dev)552 static 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 */
586 static 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
593 static const struct soc_device_data soc_device_MSHW0040 = {
594 .button_info = soc_button_MSHW0040,
595 .check = soc_device_check_MSHW0040,
596 };
597
598 static 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
611 MODULE_DEVICE_TABLE(acpi, soc_button_acpi_match);
612
613 static 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 };
621 module_platform_driver(soc_button_driver);
622
623 MODULE_LICENSE("GPL");
624