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/dmi.h> 15 #include <linux/gpio/driver.h> 16 #include <linux/gpio/machine.h> 17 #include <linux/irq.h> 18 #include <linux/module.h> 19 #include <linux/platform_device.h> 20 #include <linux/serdev.h> 21 #include <linux/string.h> 22 23 #include "x86-android-tablets.h" 24 /* For gpiochip_get_desc() which is EXPORT_SYMBOL_GPL() */ 25 #include "../../../gpio/gpiolib.h" 26 #include "../../../gpio/gpiolib-acpi.h" 27 28 static int gpiochip_find_match_label(struct gpio_chip *gc, void *data) 29 { 30 return gc->label && !strcmp(gc->label, data); 31 } 32 33 int x86_android_tablet_get_gpiod(const char *label, int pin, struct gpio_desc **desc) 34 { 35 struct gpio_desc *gpiod; 36 struct gpio_chip *chip; 37 38 chip = gpiochip_find((void *)label, gpiochip_find_match_label); 39 if (!chip) { 40 pr_err("error cannot find GPIO chip %s\n", label); 41 return -ENODEV; 42 } 43 44 gpiod = gpiochip_get_desc(chip, pin); 45 if (IS_ERR(gpiod)) { 46 pr_err("error %ld getting GPIO %s %d\n", PTR_ERR(gpiod), label, pin); 47 return PTR_ERR(gpiod); 48 } 49 50 *desc = gpiod; 51 return 0; 52 } 53 54 int x86_acpi_irq_helper_get(const struct x86_acpi_irq_data *data) 55 { 56 struct irq_fwspec fwspec = { }; 57 struct irq_domain *domain; 58 struct acpi_device *adev; 59 struct gpio_desc *gpiod; 60 unsigned int irq_type; 61 acpi_handle handle; 62 acpi_status status; 63 int irq, ret; 64 65 switch (data->type) { 66 case X86_ACPI_IRQ_TYPE_APIC: 67 /* 68 * The DSDT may already reference the GSI in a device skipped by 69 * acpi_quirk_skip_i2c_client_enumeration(). Unregister the GSI 70 * to avoid EBUSY errors in this case. 71 */ 72 acpi_unregister_gsi(data->index); 73 irq = acpi_register_gsi(NULL, data->index, data->trigger, data->polarity); 74 if (irq < 0) 75 pr_err("error %d getting APIC IRQ %d\n", irq, data->index); 76 77 return irq; 78 case X86_ACPI_IRQ_TYPE_GPIOINT: 79 /* Like acpi_dev_gpio_irq_get(), but without parsing ACPI resources */ 80 ret = x86_android_tablet_get_gpiod(data->chip, data->index, &gpiod); 81 if (ret) 82 return ret; 83 84 irq = gpiod_to_irq(gpiod); 85 if (irq < 0) { 86 pr_err("error %d getting IRQ %s %d\n", irq, data->chip, data->index); 87 return irq; 88 } 89 90 irq_type = acpi_dev_get_irq_type(data->trigger, data->polarity); 91 if (irq_type != IRQ_TYPE_NONE && irq_type != irq_get_trigger_type(irq)) 92 irq_set_irq_type(irq, irq_type); 93 94 return irq; 95 case X86_ACPI_IRQ_TYPE_PMIC: 96 status = acpi_get_handle(NULL, data->chip, &handle); 97 if (ACPI_FAILURE(status)) { 98 pr_err("error could not get %s handle\n", data->chip); 99 return -ENODEV; 100 } 101 102 adev = acpi_fetch_acpi_dev(handle); 103 if (!adev) { 104 pr_err("error could not get %s adev\n", data->chip); 105 return -ENODEV; 106 } 107 108 fwspec.fwnode = acpi_fwnode_handle(adev); 109 domain = irq_find_matching_fwspec(&fwspec, data->domain); 110 if (!domain) { 111 pr_err("error could not find IRQ domain for %s\n", data->chip); 112 return -ENODEV; 113 } 114 115 return irq_create_mapping(domain, data->index); 116 default: 117 return 0; 118 } 119 } 120 121 static int i2c_client_count; 122 static int pdev_count; 123 static int serdev_count; 124 static struct i2c_client **i2c_clients; 125 static struct platform_device **pdevs; 126 static struct serdev_device **serdevs; 127 static struct gpiod_lookup_table * const *gpiod_lookup_tables; 128 static const struct software_node *bat_swnode; 129 static void (*exit_handler)(void); 130 131 static __init int x86_instantiate_i2c_client(const struct x86_dev_info *dev_info, 132 int idx) 133 { 134 const struct x86_i2c_client_info *client_info = &dev_info->i2c_client_info[idx]; 135 struct i2c_board_info board_info = client_info->board_info; 136 struct i2c_adapter *adap; 137 acpi_handle handle; 138 acpi_status status; 139 140 board_info.irq = x86_acpi_irq_helper_get(&client_info->irq_data); 141 if (board_info.irq < 0) 142 return board_info.irq; 143 144 status = acpi_get_handle(NULL, client_info->adapter_path, &handle); 145 if (ACPI_FAILURE(status)) { 146 pr_err("Error could not get %s handle\n", client_info->adapter_path); 147 return -ENODEV; 148 } 149 150 adap = i2c_acpi_find_adapter_by_handle(handle); 151 if (!adap) { 152 pr_err("error could not get %s adapter\n", client_info->adapter_path); 153 return -ENODEV; 154 } 155 156 i2c_clients[idx] = i2c_new_client_device(adap, &board_info); 157 put_device(&adap->dev); 158 if (IS_ERR(i2c_clients[idx])) 159 return dev_err_probe(&adap->dev, PTR_ERR(i2c_clients[idx]), 160 "creating I2C-client %d\n", idx); 161 162 return 0; 163 } 164 165 static __init int x86_instantiate_serdev(const struct x86_serdev_info *info, int idx) 166 { 167 struct acpi_device *ctrl_adev, *serdev_adev; 168 struct serdev_device *serdev; 169 struct device *ctrl_dev; 170 int ret = -ENODEV; 171 172 ctrl_adev = acpi_dev_get_first_match_dev(info->ctrl_hid, info->ctrl_uid, -1); 173 if (!ctrl_adev) { 174 pr_err("error could not get %s/%s ctrl adev\n", 175 info->ctrl_hid, info->ctrl_uid); 176 return -ENODEV; 177 } 178 179 serdev_adev = acpi_dev_get_first_match_dev(info->serdev_hid, NULL, -1); 180 if (!serdev_adev) { 181 pr_err("error could not get %s serdev adev\n", info->serdev_hid); 182 goto put_ctrl_adev; 183 } 184 185 /* get_first_physical_node() returns a weak ref, no need to put() it */ 186 ctrl_dev = acpi_get_first_physical_node(ctrl_adev); 187 if (!ctrl_dev) { 188 pr_err("error could not get %s/%s ctrl physical dev\n", 189 info->ctrl_hid, info->ctrl_uid); 190 goto put_serdev_adev; 191 } 192 193 /* ctrl_dev now points to the controller's parent, get the controller */ 194 ctrl_dev = device_find_child_by_name(ctrl_dev, info->ctrl_devname); 195 if (!ctrl_dev) { 196 pr_err("error could not get %s/%s %s ctrl dev\n", 197 info->ctrl_hid, info->ctrl_uid, info->ctrl_devname); 198 goto put_serdev_adev; 199 } 200 201 serdev = serdev_device_alloc(to_serdev_controller(ctrl_dev)); 202 if (!serdev) { 203 ret = -ENOMEM; 204 goto put_serdev_adev; 205 } 206 207 ACPI_COMPANION_SET(&serdev->dev, serdev_adev); 208 acpi_device_set_enumerated(serdev_adev); 209 210 ret = serdev_device_add(serdev); 211 if (ret) { 212 dev_err(&serdev->dev, "error %d adding serdev\n", ret); 213 serdev_device_put(serdev); 214 goto put_serdev_adev; 215 } 216 217 serdevs[idx] = serdev; 218 219 put_serdev_adev: 220 acpi_dev_put(serdev_adev); 221 put_ctrl_adev: 222 acpi_dev_put(ctrl_adev); 223 return ret; 224 } 225 226 static void x86_android_tablet_cleanup(void) 227 { 228 int i; 229 230 for (i = 0; i < serdev_count; i++) { 231 if (serdevs[i]) 232 serdev_device_remove(serdevs[i]); 233 } 234 235 kfree(serdevs); 236 237 for (i = 0; i < pdev_count; i++) 238 platform_device_unregister(pdevs[i]); 239 240 kfree(pdevs); 241 242 for (i = 0; i < i2c_client_count; i++) 243 i2c_unregister_device(i2c_clients[i]); 244 245 kfree(i2c_clients); 246 247 if (exit_handler) 248 exit_handler(); 249 250 for (i = 0; gpiod_lookup_tables && gpiod_lookup_tables[i]; i++) 251 gpiod_remove_lookup_table(gpiod_lookup_tables[i]); 252 253 software_node_unregister(bat_swnode); 254 } 255 256 static __init int x86_android_tablet_init(void) 257 { 258 const struct x86_dev_info *dev_info; 259 const struct dmi_system_id *id; 260 struct gpio_chip *chip; 261 int i, ret = 0; 262 263 id = dmi_first_match(x86_android_tablet_ids); 264 if (!id) 265 return -ENODEV; 266 267 dev_info = id->driver_data; 268 269 /* 270 * The broken DSDTs on these devices often also include broken 271 * _AEI (ACPI Event Interrupt) handlers, disable these. 272 */ 273 if (dev_info->invalid_aei_gpiochip) { 274 chip = gpiochip_find(dev_info->invalid_aei_gpiochip, 275 gpiochip_find_match_label); 276 if (!chip) { 277 pr_err("error cannot find GPIO chip %s\n", dev_info->invalid_aei_gpiochip); 278 return -ENODEV; 279 } 280 acpi_gpiochip_free_interrupts(chip); 281 } 282 283 /* 284 * Since this runs from module_init() it cannot use -EPROBE_DEFER, 285 * instead pre-load any modules which are listed as requirements. 286 */ 287 for (i = 0; dev_info->modules && dev_info->modules[i]; i++) 288 request_module(dev_info->modules[i]); 289 290 bat_swnode = dev_info->bat_swnode; 291 if (bat_swnode) { 292 ret = software_node_register(bat_swnode); 293 if (ret) 294 return ret; 295 } 296 297 gpiod_lookup_tables = dev_info->gpiod_lookup_tables; 298 for (i = 0; gpiod_lookup_tables && gpiod_lookup_tables[i]; i++) 299 gpiod_add_lookup_table(gpiod_lookup_tables[i]); 300 301 if (dev_info->init) { 302 ret = dev_info->init(); 303 if (ret < 0) { 304 x86_android_tablet_cleanup(); 305 return ret; 306 } 307 exit_handler = dev_info->exit; 308 } 309 310 i2c_clients = kcalloc(dev_info->i2c_client_count, sizeof(*i2c_clients), GFP_KERNEL); 311 if (!i2c_clients) { 312 x86_android_tablet_cleanup(); 313 return -ENOMEM; 314 } 315 316 i2c_client_count = dev_info->i2c_client_count; 317 for (i = 0; i < i2c_client_count; i++) { 318 ret = x86_instantiate_i2c_client(dev_info, i); 319 if (ret < 0) { 320 x86_android_tablet_cleanup(); 321 return ret; 322 } 323 } 324 325 /* + 1 to make space for (optional) gpio_keys_button pdev */ 326 pdevs = kcalloc(dev_info->pdev_count + 1, sizeof(*pdevs), GFP_KERNEL); 327 if (!pdevs) { 328 x86_android_tablet_cleanup(); 329 return -ENOMEM; 330 } 331 332 pdev_count = dev_info->pdev_count; 333 for (i = 0; i < pdev_count; i++) { 334 pdevs[i] = platform_device_register_full(&dev_info->pdev_info[i]); 335 if (IS_ERR(pdevs[i])) { 336 x86_android_tablet_cleanup(); 337 return PTR_ERR(pdevs[i]); 338 } 339 } 340 341 serdevs = kcalloc(dev_info->serdev_count, sizeof(*serdevs), GFP_KERNEL); 342 if (!serdevs) { 343 x86_android_tablet_cleanup(); 344 return -ENOMEM; 345 } 346 347 serdev_count = dev_info->serdev_count; 348 for (i = 0; i < serdev_count; i++) { 349 ret = x86_instantiate_serdev(&dev_info->serdev_info[i], i); 350 if (ret < 0) { 351 x86_android_tablet_cleanup(); 352 return ret; 353 } 354 } 355 356 if (dev_info->gpio_button) { 357 struct gpio_keys_platform_data pdata = { 358 .buttons = &dev_info->gpio_button->button, 359 .nbuttons = 1, 360 }; 361 struct gpio_desc *gpiod; 362 363 /* Get GPIO for the gpio-button */ 364 ret = x86_android_tablet_get_gpiod(dev_info->gpio_button->chip, 365 dev_info->gpio_button->pin, &gpiod); 366 if (ret < 0) { 367 x86_android_tablet_cleanup(); 368 return ret; 369 } 370 371 dev_info->gpio_button->button.gpio = desc_to_gpio(gpiod); 372 373 pdevs[pdev_count] = platform_device_register_data(NULL, "gpio-keys", 374 PLATFORM_DEVID_AUTO, 375 &pdata, sizeof(pdata)); 376 if (IS_ERR(pdevs[pdev_count])) { 377 x86_android_tablet_cleanup(); 378 return PTR_ERR(pdevs[pdev_count]); 379 } 380 pdev_count++; 381 } 382 383 return 0; 384 } 385 386 module_init(x86_android_tablet_init); 387 module_exit(x86_android_tablet_cleanup); 388 389 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); 390 MODULE_DESCRIPTION("X86 Android tablets DSDT fixups driver"); 391 MODULE_LICENSE("GPL"); 392