1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * DMI based code to deal with broken DSDTs on X86 tablets which ship with 4 * Android as (part of) the factory image. The factory kernels shipped on these 5 * devices typically have a bunch of things hardcoded, rather than specified 6 * in their DSDT. 7 * 8 * Copyright (C) 2021-2023 Hans de Goede <hdegoede@redhat.com> 9 */ 10 11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 12 13 #include <linux/acpi.h> 14 #include <linux/device.h> 15 #include <linux/dmi.h> 16 #include <linux/gpio/consumer.h> 17 #include <linux/gpio/machine.h> 18 #include <linux/irq.h> 19 #include <linux/module.h> 20 #include <linux/pci.h> 21 #include <linux/platform_device.h> 22 #include <linux/serdev.h> 23 #include <linux/string.h> 24 25 #include "x86-android-tablets.h" 26 #include "../serdev_helpers.h" 27 28 static struct platform_device *x86_android_tablet_device; 29 30 /* 31 * This helper allows getting a GPIO descriptor *before* the actual device 32 * consuming it has been instantiated. This function MUST only be used to 33 * handle this special case such as, e.g.: 34 * 35 * 1. Getting an IRQ from a GPIO for i2c_board_info.irq which is passed to 36 * i2c_client_new() to instantiate i2c_client-s; or 37 * 2. Calling desc_to_gpio() to get an old style GPIO number for gpio-keys 38 * platform_data which still uses old style GPIO numbers. 39 * 40 * Since the consuming device has not been instantiated yet a dynamic lookup 41 * is generated using the special x86_android_tablet device for dev_id. 42 * 43 * For normal GPIO lookups a standard static struct gpiod_lookup_table MUST be used. 44 */ 45 int x86_android_tablet_get_gpiod(const char *chip, int pin, const char *con_id, 46 bool active_low, enum gpiod_flags dflags, 47 struct gpio_desc **desc) 48 { 49 struct gpiod_lookup_table *lookup; 50 struct gpio_desc *gpiod; 51 52 lookup = kzalloc(struct_size(lookup, table, 2), GFP_KERNEL); 53 if (!lookup) 54 return -ENOMEM; 55 56 lookup->dev_id = KBUILD_MODNAME; 57 lookup->table[0] = 58 GPIO_LOOKUP(chip, pin, con_id, active_low ? GPIO_ACTIVE_LOW : GPIO_ACTIVE_HIGH); 59 60 gpiod_add_lookup_table(lookup); 61 gpiod = devm_gpiod_get(&x86_android_tablet_device->dev, con_id, dflags); 62 gpiod_remove_lookup_table(lookup); 63 kfree(lookup); 64 65 if (IS_ERR(gpiod)) { 66 pr_err("error %ld getting GPIO %s %d\n", PTR_ERR(gpiod), chip, pin); 67 return PTR_ERR(gpiod); 68 } 69 70 if (desc) 71 *desc = gpiod; 72 73 return 0; 74 } 75 76 int x86_acpi_irq_helper_get(const struct x86_acpi_irq_data *data) 77 { 78 struct irq_fwspec fwspec = { }; 79 struct irq_domain *domain; 80 struct acpi_device *adev; 81 struct gpio_desc *gpiod; 82 unsigned int irq_type; 83 acpi_handle handle; 84 acpi_status status; 85 int irq, ret; 86 87 switch (data->type) { 88 case X86_ACPI_IRQ_TYPE_APIC: 89 /* 90 * The DSDT may already reference the GSI in a device skipped by 91 * acpi_quirk_skip_i2c_client_enumeration(). Unregister the GSI 92 * to avoid -EBUSY errors in this case. 93 */ 94 acpi_unregister_gsi(data->index); 95 irq = acpi_register_gsi(NULL, data->index, data->trigger, data->polarity); 96 if (irq < 0) 97 pr_err("error %d getting APIC IRQ %d\n", irq, data->index); 98 99 return irq; 100 case X86_ACPI_IRQ_TYPE_GPIOINT: 101 /* Like acpi_dev_gpio_irq_get(), but without parsing ACPI resources */ 102 ret = x86_android_tablet_get_gpiod(data->chip, data->index, data->con_id, 103 false, GPIOD_ASIS, &gpiod); 104 if (ret) 105 return ret; 106 107 irq = gpiod_to_irq(gpiod); 108 if (irq < 0) { 109 pr_err("error %d getting IRQ %s %d\n", irq, data->chip, data->index); 110 return irq; 111 } 112 113 irq_type = acpi_dev_get_irq_type(data->trigger, data->polarity); 114 if (irq_type != IRQ_TYPE_NONE && irq_type != irq_get_trigger_type(irq)) 115 irq_set_irq_type(irq, irq_type); 116 117 if (data->free_gpio) 118 devm_gpiod_put(&x86_android_tablet_device->dev, gpiod); 119 120 return irq; 121 case X86_ACPI_IRQ_TYPE_PMIC: 122 status = acpi_get_handle(NULL, data->chip, &handle); 123 if (ACPI_FAILURE(status)) { 124 pr_err("error could not get %s handle\n", data->chip); 125 return -ENODEV; 126 } 127 128 adev = acpi_fetch_acpi_dev(handle); 129 if (!adev) { 130 pr_err("error could not get %s adev\n", data->chip); 131 return -ENODEV; 132 } 133 134 fwspec.fwnode = acpi_fwnode_handle(adev); 135 domain = irq_find_matching_fwspec(&fwspec, data->domain); 136 if (!domain) { 137 pr_err("error could not find IRQ domain for %s\n", data->chip); 138 return -ENODEV; 139 } 140 141 return irq_create_mapping(domain, data->index); 142 default: 143 return 0; 144 } 145 } 146 147 static int i2c_client_count; 148 static int spi_dev_count; 149 static int pdev_count; 150 static int serdev_count; 151 static struct i2c_client **i2c_clients; 152 static struct spi_device **spi_devs; 153 static struct platform_device **pdevs; 154 static struct serdev_device **serdevs; 155 static struct gpio_keys_button *buttons; 156 static struct gpiod_lookup_table * const *gpiod_lookup_tables; 157 static const struct software_node *bat_swnode; 158 static void (*exit_handler)(void); 159 160 static __init struct i2c_adapter * 161 get_i2c_adap_by_handle(const struct x86_i2c_client_info *client_info) 162 { 163 acpi_handle handle; 164 acpi_status status; 165 166 status = acpi_get_handle(NULL, client_info->adapter_path, &handle); 167 if (ACPI_FAILURE(status)) { 168 pr_err("Error could not get %s handle\n", client_info->adapter_path); 169 return NULL; 170 } 171 172 return i2c_acpi_find_adapter_by_handle(handle); 173 } 174 175 static __init int match_parent(struct device *dev, const void *data) 176 { 177 return dev->parent == data; 178 } 179 180 static __init struct i2c_adapter * 181 get_i2c_adap_by_pci_parent(const struct x86_i2c_client_info *client_info) 182 { 183 struct i2c_adapter *adap = NULL; 184 struct device *pdev, *adap_dev; 185 186 pdev = bus_find_device_by_name(&pci_bus_type, NULL, client_info->adapter_path); 187 if (!pdev) { 188 pr_err("Error could not find %s PCI device\n", client_info->adapter_path); 189 return NULL; 190 } 191 192 adap_dev = bus_find_device(&i2c_bus_type, NULL, pdev, match_parent); 193 if (adap_dev) { 194 adap = i2c_verify_adapter(adap_dev); 195 if (!adap) 196 put_device(adap_dev); 197 } 198 199 put_device(pdev); 200 201 return adap; 202 } 203 204 static __init int x86_instantiate_i2c_client(const struct x86_dev_info *dev_info, 205 int idx) 206 { 207 const struct x86_i2c_client_info *client_info = &dev_info->i2c_client_info[idx]; 208 struct i2c_board_info board_info = client_info->board_info; 209 struct i2c_adapter *adap; 210 211 board_info.irq = x86_acpi_irq_helper_get(&client_info->irq_data); 212 if (board_info.irq < 0) 213 return board_info.irq; 214 215 if (dev_info->use_pci) 216 adap = get_i2c_adap_by_pci_parent(client_info); 217 else 218 adap = get_i2c_adap_by_handle(client_info); 219 220 if (!adap) { 221 pr_err("error could not get %s adapter\n", client_info->adapter_path); 222 return -ENODEV; 223 } 224 225 i2c_clients[idx] = i2c_new_client_device(adap, &board_info); 226 put_device(&adap->dev); 227 if (IS_ERR(i2c_clients[idx])) 228 return dev_err_probe(&adap->dev, PTR_ERR(i2c_clients[idx]), 229 "creating I2C-client %d\n", idx); 230 231 return 0; 232 } 233 234 static __init int x86_instantiate_spi_dev(const struct x86_dev_info *dev_info, int idx) 235 { 236 const struct x86_spi_dev_info *spi_dev_info = &dev_info->spi_dev_info[idx]; 237 struct spi_board_info board_info = spi_dev_info->board_info; 238 struct spi_controller *controller; 239 struct acpi_device *adev; 240 acpi_handle handle; 241 acpi_status status; 242 243 board_info.irq = x86_acpi_irq_helper_get(&spi_dev_info->irq_data); 244 if (board_info.irq < 0) 245 return board_info.irq; 246 247 status = acpi_get_handle(NULL, spi_dev_info->ctrl_path, &handle); 248 if (ACPI_FAILURE(status)) { 249 pr_err("Error could not get %s handle\n", spi_dev_info->ctrl_path); 250 return -ENODEV; 251 } 252 253 adev = acpi_fetch_acpi_dev(handle); 254 if (!adev) { 255 pr_err("Error could not get adev for %s\n", spi_dev_info->ctrl_path); 256 return -ENODEV; 257 } 258 259 controller = acpi_spi_find_controller_by_adev(adev); 260 if (!controller) { 261 pr_err("Error could not get SPI controller for %s\n", spi_dev_info->ctrl_path); 262 return -ENODEV; 263 } 264 265 spi_devs[idx] = spi_new_device(controller, &board_info); 266 put_device(&controller->dev); 267 if (!spi_devs[idx]) 268 return -ENOMEM; 269 270 return 0; 271 } 272 273 static __init struct device * 274 get_serdev_controller_by_pci_parent(const struct x86_serdev_info *info) 275 { 276 struct pci_dev *pdev; 277 278 pdev = pci_get_domain_bus_and_slot(0, 0, info->ctrl.pci.devfn); 279 if (!pdev) 280 return ERR_PTR(-EPROBE_DEFER); 281 282 /* This puts our reference on pdev and returns a ref on the ctrl */ 283 return get_serdev_controller_from_parent(&pdev->dev, 0, info->ctrl_devname); 284 } 285 286 static __init int x86_instantiate_serdev(const struct x86_dev_info *dev_info, int idx) 287 { 288 const struct x86_serdev_info *info = &dev_info->serdev_info[idx]; 289 struct acpi_device *serdev_adev; 290 struct serdev_device *serdev; 291 struct device *ctrl_dev; 292 int ret = -ENODEV; 293 294 if (dev_info->use_pci) 295 ctrl_dev = get_serdev_controller_by_pci_parent(info); 296 else 297 ctrl_dev = get_serdev_controller(info->ctrl.acpi.hid, info->ctrl.acpi.uid, 298 0, info->ctrl_devname); 299 if (IS_ERR(ctrl_dev)) 300 return PTR_ERR(ctrl_dev); 301 302 serdev_adev = acpi_dev_get_first_match_dev(info->serdev_hid, NULL, -1); 303 if (!serdev_adev) { 304 pr_err("error could not get %s serdev adev\n", info->serdev_hid); 305 goto put_ctrl_dev; 306 } 307 308 serdev = serdev_device_alloc(to_serdev_controller(ctrl_dev)); 309 if (!serdev) { 310 ret = -ENOMEM; 311 goto put_serdev_adev; 312 } 313 314 ACPI_COMPANION_SET(&serdev->dev, serdev_adev); 315 acpi_device_set_enumerated(serdev_adev); 316 317 ret = serdev_device_add(serdev); 318 if (ret) { 319 dev_err(&serdev->dev, "error %d adding serdev\n", ret); 320 serdev_device_put(serdev); 321 goto put_serdev_adev; 322 } 323 324 serdevs[idx] = serdev; 325 326 put_serdev_adev: 327 acpi_dev_put(serdev_adev); 328 put_ctrl_dev: 329 put_device(ctrl_dev); 330 return ret; 331 } 332 333 static void x86_android_tablet_remove(struct platform_device *pdev) 334 { 335 int i; 336 337 for (i = serdev_count - 1; i >= 0; i--) { 338 if (serdevs[i]) 339 serdev_device_remove(serdevs[i]); 340 } 341 342 kfree(serdevs); 343 344 for (i = pdev_count - 1; i >= 0; i--) 345 platform_device_unregister(pdevs[i]); 346 347 kfree(pdevs); 348 kfree(buttons); 349 350 for (i = spi_dev_count - 1; i >= 0; i--) 351 spi_unregister_device(spi_devs[i]); 352 353 kfree(spi_devs); 354 355 for (i = i2c_client_count - 1; i >= 0; i--) 356 i2c_unregister_device(i2c_clients[i]); 357 358 kfree(i2c_clients); 359 360 if (exit_handler) 361 exit_handler(); 362 363 for (i = 0; gpiod_lookup_tables && gpiod_lookup_tables[i]; i++) 364 gpiod_remove_lookup_table(gpiod_lookup_tables[i]); 365 366 software_node_unregister(bat_swnode); 367 } 368 369 static __init int x86_android_tablet_probe(struct platform_device *pdev) 370 { 371 const struct x86_dev_info *dev_info; 372 const struct dmi_system_id *id; 373 int i, ret = 0; 374 375 id = dmi_first_match(x86_android_tablet_ids); 376 if (!id) 377 return -ENODEV; 378 379 dev_info = id->driver_data; 380 /* Allow x86_android_tablet_device use before probe() exits */ 381 x86_android_tablet_device = pdev; 382 383 /* 384 * Since this runs from module_init() it cannot use -EPROBE_DEFER, 385 * instead pre-load any modules which are listed as requirements. 386 */ 387 for (i = 0; dev_info->modules && dev_info->modules[i]; i++) 388 request_module(dev_info->modules[i]); 389 390 bat_swnode = dev_info->bat_swnode; 391 if (bat_swnode) { 392 ret = software_node_register(bat_swnode); 393 if (ret) 394 return ret; 395 } 396 397 gpiod_lookup_tables = dev_info->gpiod_lookup_tables; 398 for (i = 0; gpiod_lookup_tables && gpiod_lookup_tables[i]; i++) 399 gpiod_add_lookup_table(gpiod_lookup_tables[i]); 400 401 if (dev_info->init) { 402 ret = dev_info->init(&pdev->dev); 403 if (ret < 0) { 404 x86_android_tablet_remove(pdev); 405 return ret; 406 } 407 exit_handler = dev_info->exit; 408 } 409 410 i2c_clients = kcalloc(dev_info->i2c_client_count, sizeof(*i2c_clients), GFP_KERNEL); 411 if (!i2c_clients) { 412 x86_android_tablet_remove(pdev); 413 return -ENOMEM; 414 } 415 416 i2c_client_count = dev_info->i2c_client_count; 417 for (i = 0; i < i2c_client_count; i++) { 418 ret = x86_instantiate_i2c_client(dev_info, i); 419 if (ret < 0) { 420 x86_android_tablet_remove(pdev); 421 return ret; 422 } 423 } 424 425 spi_devs = kcalloc(dev_info->spi_dev_count, sizeof(*spi_devs), GFP_KERNEL); 426 if (!spi_devs) { 427 x86_android_tablet_remove(pdev); 428 return -ENOMEM; 429 } 430 431 spi_dev_count = dev_info->spi_dev_count; 432 for (i = 0; i < spi_dev_count; i++) { 433 ret = x86_instantiate_spi_dev(dev_info, i); 434 if (ret < 0) { 435 x86_android_tablet_remove(pdev); 436 return ret; 437 } 438 } 439 440 /* + 1 to make space for the (optional) gpio_keys_button platform device */ 441 pdevs = kcalloc(dev_info->pdev_count + 1, sizeof(*pdevs), GFP_KERNEL); 442 if (!pdevs) { 443 x86_android_tablet_remove(pdev); 444 return -ENOMEM; 445 } 446 447 pdev_count = dev_info->pdev_count; 448 for (i = 0; i < pdev_count; i++) { 449 pdevs[i] = platform_device_register_full(&dev_info->pdev_info[i]); 450 if (IS_ERR(pdevs[i])) { 451 ret = PTR_ERR(pdevs[i]); 452 x86_android_tablet_remove(pdev); 453 return ret; 454 } 455 } 456 457 serdevs = kcalloc(dev_info->serdev_count, sizeof(*serdevs), GFP_KERNEL); 458 if (!serdevs) { 459 x86_android_tablet_remove(pdev); 460 return -ENOMEM; 461 } 462 463 serdev_count = dev_info->serdev_count; 464 for (i = 0; i < serdev_count; i++) { 465 ret = x86_instantiate_serdev(dev_info, i); 466 if (ret < 0) { 467 x86_android_tablet_remove(pdev); 468 return ret; 469 } 470 } 471 472 if (dev_info->gpio_button_count) { 473 struct gpio_keys_platform_data pdata = { }; 474 struct gpio_desc *gpiod; 475 476 buttons = kcalloc(dev_info->gpio_button_count, sizeof(*buttons), GFP_KERNEL); 477 if (!buttons) { 478 x86_android_tablet_remove(pdev); 479 return -ENOMEM; 480 } 481 482 for (i = 0; i < dev_info->gpio_button_count; i++) { 483 ret = x86_android_tablet_get_gpiod(dev_info->gpio_button[i].chip, 484 dev_info->gpio_button[i].pin, 485 dev_info->gpio_button[i].button.desc, 486 false, GPIOD_IN, &gpiod); 487 if (ret < 0) { 488 x86_android_tablet_remove(pdev); 489 return ret; 490 } 491 492 buttons[i] = dev_info->gpio_button[i].button; 493 buttons[i].gpio = desc_to_gpio(gpiod); 494 /* Release GPIO descriptor so that gpio-keys can request it */ 495 devm_gpiod_put(&x86_android_tablet_device->dev, gpiod); 496 } 497 498 pdata.buttons = buttons; 499 pdata.nbuttons = dev_info->gpio_button_count; 500 501 pdevs[pdev_count] = platform_device_register_data(&pdev->dev, "gpio-keys", 502 PLATFORM_DEVID_AUTO, 503 &pdata, sizeof(pdata)); 504 if (IS_ERR(pdevs[pdev_count])) { 505 ret = PTR_ERR(pdevs[pdev_count]); 506 x86_android_tablet_remove(pdev); 507 return ret; 508 } 509 pdev_count++; 510 } 511 512 return 0; 513 } 514 515 static struct platform_driver x86_android_tablet_driver = { 516 .driver = { 517 .name = KBUILD_MODNAME, 518 }, 519 .remove = x86_android_tablet_remove, 520 }; 521 522 static int __init x86_android_tablet_init(void) 523 { 524 x86_android_tablet_device = platform_create_bundle(&x86_android_tablet_driver, 525 x86_android_tablet_probe, 526 NULL, 0, NULL, 0); 527 528 return PTR_ERR_OR_ZERO(x86_android_tablet_device); 529 } 530 module_init(x86_android_tablet_init); 531 532 static void __exit x86_android_tablet_exit(void) 533 { 534 platform_device_unregister(x86_android_tablet_device); 535 platform_driver_unregister(&x86_android_tablet_driver); 536 } 537 module_exit(x86_android_tablet_exit); 538 539 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); 540 MODULE_DESCRIPTION("X86 Android tablets DSDT fixups driver"); 541 MODULE_LICENSE("GPL"); 542