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 * Get the Nth GPIO number from the ACPI object. 113 */ 114 static 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 } 130 131 static struct platform_device * 132 soc_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; 218 219 err_free_mem: 220 devm_kfree(&pdev->dev, gpio_keys_pdata); 221 return ERR_PTR(error); 222 } 223 224 static 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 */ 233 static 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 */ 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 302 }; 303 304 /* Parse ACPI0011 _DSD button descriptors */ 305 static 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 } 378 379 out: 380 kfree(buf.pointer); 381 return button_info; 382 } 383 384 static 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 } 396 397 static 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 */ 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 }, 468 { } 469 }; 470 471 static const struct soc_device_data soc_device_PNP0C40 = { 472 .button_info = soc_button_PNP0C40, 473 }; 474 475 static const struct soc_button_info soc_button_INT33D3[] = { 476 { "tablet_mode", 0, EV_SW, SW_TABLET_MODE, false, false, false }, 477 { } 478 }; 479 480 static 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 */ 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 }, 498 { } 499 }; 500 501 static 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 515 static const guid_t MSHW0040_DSM_UUID = 516 GUID_INIT(0x6fd05c69, 0xcde3, 0x49f4, 0x95, 0xed, 0xab, 0x16, 0x65, 517 0x49, 0x80, 0x35); 518 519 static 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 */ 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 }, 557 { } 558 }; 559 560 static const struct soc_device_data soc_device_MSHW0040 = { 561 .button_info = soc_button_MSHW0040, 562 .check = soc_device_check_MSHW0040, 563 }; 564 565 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 }, 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 }; 577 578 MODULE_DEVICE_TABLE(acpi, soc_button_acpi_match); 579 580 static 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 }; 588 module_platform_driver(soc_button_driver); 589 590 MODULE_LICENSE("GPL"); 591