projects/linux·blob cba5e972 · refs

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