1 // SPDX-License-Identifier: GPL-2.0 2 /* Author: Dan Scally <djrscally@gmail.com> */ 3 4 #include <linux/acpi.h> 5 #include <linux/device.h> 6 #include <linux/gpio/consumer.h> 7 #include <linux/gpio/machine.h> 8 #include <linux/i2c.h> 9 #include <linux/kernel.h> 10 #include <linux/module.h> 11 #include <linux/overflow.h> 12 #include <linux/platform_device.h> 13 #include <linux/uuid.h> 14 15 #include "common.h" 16 17 /* 18 * 79234640-9e10-4fea-a5c1-b5aa8b19756f 19 * This _DSM GUID returns information about the GPIO lines mapped to a 20 * discrete INT3472 device. Function number 1 returns a count of the GPIO 21 * lines that are mapped. Subsequent functions return 32 bit ints encoding 22 * information about the GPIO line, including its purpose. 23 */ 24 static const guid_t int3472_gpio_guid = 25 GUID_INIT(0x79234640, 0x9e10, 0x4fea, 26 0xa5, 0xc1, 0xb5, 0xaa, 0x8b, 0x19, 0x75, 0x6f); 27 28 /* 29 * 822ace8f-2814-4174-a56b-5f029fe079ee 30 * This _DSM GUID returns a string from the sensor device, which acts as a 31 * module identifier. 32 */ 33 static const guid_t cio2_sensor_module_guid = 34 GUID_INIT(0x822ace8f, 0x2814, 0x4174, 35 0xa5, 0x6b, 0x5f, 0x02, 0x9f, 0xe0, 0x79, 0xee); 36 37 /* 38 * Here follows platform specific mapping information that we can pass to 39 * the functions mapping resources to the sensors. Where the sensors have 40 * a power enable pin defined in DSDT we need to provide a supply name so 41 * the sensor drivers can find the regulator. The device name will be derived 42 * from the sensor's ACPI device within the code. Optionally, we can provide a 43 * NULL terminated array of function name mappings to deal with any platform 44 * specific deviations from the documented behaviour of GPIOs. 45 * 46 * Map a GPIO function name to NULL to prevent the driver from mapping that 47 * GPIO at all. 48 */ 49 50 static const struct int3472_gpio_function_remap ov2680_gpio_function_remaps[] = { 51 { "reset", NULL }, 52 { "powerdown", "reset" }, 53 { } 54 }; 55 56 static const struct int3472_sensor_config int3472_sensor_configs[] = { 57 /* Lenovo Miix 510-12ISK - OV2680, Front */ 58 { "GNDF140809R", { 0 }, ov2680_gpio_function_remaps }, 59 /* Lenovo Miix 510-12ISK - OV5648, Rear */ 60 { "GEFF150023R", REGULATOR_SUPPLY("avdd", NULL), NULL }, 61 /* Surface Go 1&2 - OV5693, Front */ 62 { "YHCU", REGULATOR_SUPPLY("avdd", NULL), NULL }, 63 }; 64 65 static const struct int3472_sensor_config * 66 skl_int3472_get_sensor_module_config(struct int3472_discrete_device *int3472) 67 { 68 union acpi_object *obj; 69 unsigned int i; 70 71 obj = acpi_evaluate_dsm_typed(int3472->sensor->handle, 72 &cio2_sensor_module_guid, 0x00, 73 0x01, NULL, ACPI_TYPE_STRING); 74 75 if (!obj) { 76 dev_err(int3472->dev, 77 "Failed to get sensor module string from _DSM\n"); 78 return ERR_PTR(-ENODEV); 79 } 80 81 for (i = 0; i < ARRAY_SIZE(int3472_sensor_configs); i++) { 82 if (!strcmp(int3472_sensor_configs[i].sensor_module_name, 83 obj->string.pointer)) 84 break; 85 } 86 87 ACPI_FREE(obj); 88 89 if (i >= ARRAY_SIZE(int3472_sensor_configs)) 90 return ERR_PTR(-EINVAL); 91 92 return &int3472_sensor_configs[i]; 93 } 94 95 static int skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device *int3472, 96 struct acpi_resource_gpio *agpio, 97 const char *func, u32 polarity) 98 { 99 const struct int3472_sensor_config *sensor_config; 100 char *path = agpio->resource_source.string_ptr; 101 struct gpiod_lookup *table_entry; 102 struct acpi_device *adev; 103 acpi_handle handle; 104 acpi_status status; 105 106 if (int3472->n_sensor_gpios >= INT3472_MAX_SENSOR_GPIOS) { 107 dev_warn(int3472->dev, "Too many GPIOs mapped\n"); 108 return -EINVAL; 109 } 110 111 sensor_config = int3472->sensor_config; 112 if (!IS_ERR(sensor_config) && sensor_config->function_maps) { 113 const struct int3472_gpio_function_remap *remap; 114 115 for (remap = sensor_config->function_maps; remap->documented; remap++) { 116 if (!strcmp(func, remap->documented)) { 117 func = remap->actual; 118 break; 119 } 120 } 121 } 122 123 /* Functions mapped to NULL should not be mapped to the sensor */ 124 if (!func) 125 return 0; 126 127 status = acpi_get_handle(NULL, path, &handle); 128 if (ACPI_FAILURE(status)) 129 return -EINVAL; 130 131 adev = acpi_fetch_acpi_dev(handle); 132 if (!adev) 133 return -ENODEV; 134 135 table_entry = &int3472->gpios.table[int3472->n_sensor_gpios]; 136 table_entry->key = acpi_dev_name(adev); 137 table_entry->chip_hwnum = agpio->pin_table[0]; 138 table_entry->con_id = func; 139 table_entry->idx = 0; 140 table_entry->flags = polarity; 141 142 int3472->n_sensor_gpios++; 143 144 return 0; 145 } 146 147 static void int3472_get_func_and_polarity(u8 type, const char **func, u32 *polarity) 148 { 149 switch (type) { 150 case INT3472_GPIO_TYPE_RESET: 151 *func = "reset"; 152 *polarity = GPIO_ACTIVE_LOW; 153 break; 154 case INT3472_GPIO_TYPE_POWERDOWN: 155 *func = "powerdown"; 156 *polarity = GPIO_ACTIVE_LOW; 157 break; 158 case INT3472_GPIO_TYPE_CLK_ENABLE: 159 *func = "clk-enable"; 160 *polarity = GPIO_ACTIVE_HIGH; 161 break; 162 case INT3472_GPIO_TYPE_PRIVACY_LED: 163 *func = "privacy-led"; 164 *polarity = GPIO_ACTIVE_HIGH; 165 break; 166 case INT3472_GPIO_TYPE_POWER_ENABLE: 167 *func = "power-enable"; 168 *polarity = GPIO_ACTIVE_HIGH; 169 break; 170 default: 171 *func = "unknown"; 172 *polarity = GPIO_ACTIVE_HIGH; 173 break; 174 } 175 } 176 177 /** 178 * skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor 179 * @ares: A pointer to a &struct acpi_resource 180 * @data: A pointer to a &struct int3472_discrete_device 181 * 182 * This function handles GPIO resources that are against an INT3472 183 * ACPI device, by checking the value of the corresponding _DSM entry. 184 * This will return a 32bit int, where the lowest byte represents the 185 * function of the GPIO pin: 186 * 187 * 0x00 Reset 188 * 0x01 Power down 189 * 0x0b Power enable 190 * 0x0c Clock enable 191 * 0x0d Privacy LED 192 * 193 * There are some known platform specific quirks where that does not quite 194 * hold up; for example where a pin with type 0x01 (Power down) is mapped to 195 * a sensor pin that performs a reset function or entries in _CRS and _DSM that 196 * do not actually correspond to a physical connection. These will be handled 197 * by the mapping sub-functions. 198 * 199 * GPIOs will either be mapped directly to the sensor device or else used 200 * to create clocks and regulators via the usual frameworks. 201 * 202 * Return: 203 * * 1 - To continue the loop 204 * * 0 - When all resources found are handled properly. 205 * * -EINVAL - If the resource is not a GPIO IO resource 206 * * -ENODEV - If the resource has no corresponding _DSM entry 207 * * -Other - Errors propagated from one of the sub-functions. 208 */ 209 static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares, 210 void *data) 211 { 212 struct int3472_discrete_device *int3472 = data; 213 struct acpi_resource_gpio *agpio; 214 union acpi_object *obj; 215 u8 active_value, type; 216 const char *err_msg; 217 const char *func; 218 u32 polarity; 219 int ret; 220 221 if (!acpi_gpio_get_io_resource(ares, &agpio)) 222 return 1; 223 224 /* 225 * ngpios + 2 because the index of this _DSM function is 1-based and 226 * the first function is just a count. 227 */ 228 obj = acpi_evaluate_dsm_typed(int3472->adev->handle, 229 &int3472_gpio_guid, 0x00, 230 int3472->ngpios + 2, 231 NULL, ACPI_TYPE_INTEGER); 232 233 if (!obj) { 234 dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n", 235 agpio->pin_table[0]); 236 return 1; 237 } 238 239 type = obj->integer.value & 0xff; 240 241 int3472_get_func_and_polarity(type, &func, &polarity); 242 243 /* If bits 31-24 of the _DSM entry are all 0 then the signal is inverted */ 244 active_value = obj->integer.value >> 24; 245 if (!active_value) 246 polarity ^= GPIO_ACTIVE_LOW; 247 248 dev_dbg(int3472->dev, "%s %s pin %d active-%s\n", func, 249 agpio->resource_source.string_ptr, agpio->pin_table[0], 250 (polarity == GPIO_ACTIVE_HIGH) ? "high" : "low"); 251 252 switch (type) { 253 case INT3472_GPIO_TYPE_RESET: 254 case INT3472_GPIO_TYPE_POWERDOWN: 255 ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, func, polarity); 256 if (ret) 257 err_msg = "Failed to map GPIO pin to sensor\n"; 258 259 break; 260 case INT3472_GPIO_TYPE_CLK_ENABLE: 261 ret = skl_int3472_register_clock(int3472, agpio, polarity); 262 if (ret) 263 err_msg = "Failed to register clock\n"; 264 265 break; 266 case INT3472_GPIO_TYPE_PRIVACY_LED: 267 ret = skl_int3472_register_pled(int3472, agpio, polarity); 268 if (ret) 269 err_msg = "Failed to register LED\n"; 270 271 break; 272 case INT3472_GPIO_TYPE_POWER_ENABLE: 273 ret = skl_int3472_register_regulator(int3472, agpio); 274 if (ret) 275 err_msg = "Failed to map regulator to sensor\n"; 276 277 break; 278 default: 279 dev_warn(int3472->dev, 280 "GPIO type 0x%02x unknown; the sensor may not work\n", 281 type); 282 ret = 1; 283 break; 284 } 285 286 int3472->ngpios++; 287 ACPI_FREE(obj); 288 289 if (ret < 0) 290 return dev_err_probe(int3472->dev, ret, err_msg); 291 292 return ret; 293 } 294 295 static int skl_int3472_parse_crs(struct int3472_discrete_device *int3472) 296 { 297 LIST_HEAD(resource_list); 298 int ret; 299 300 /* 301 * No error check, because not having a sensor config is not necessarily 302 * a failure mode. 303 */ 304 int3472->sensor_config = skl_int3472_get_sensor_module_config(int3472); 305 306 ret = acpi_dev_get_resources(int3472->adev, &resource_list, 307 skl_int3472_handle_gpio_resources, 308 int3472); 309 if (ret < 0) 310 return ret; 311 312 acpi_dev_free_resource_list(&resource_list); 313 314 int3472->gpios.dev_id = int3472->sensor_name; 315 gpiod_add_lookup_table(&int3472->gpios); 316 317 return 0; 318 } 319 320 static int skl_int3472_discrete_remove(struct platform_device *pdev) 321 { 322 struct int3472_discrete_device *int3472 = platform_get_drvdata(pdev); 323 324 gpiod_remove_lookup_table(&int3472->gpios); 325 326 skl_int3472_unregister_clock(int3472); 327 skl_int3472_unregister_pled(int3472); 328 skl_int3472_unregister_regulator(int3472); 329 330 return 0; 331 } 332 333 static int skl_int3472_discrete_probe(struct platform_device *pdev) 334 { 335 struct acpi_device *adev = ACPI_COMPANION(&pdev->dev); 336 struct int3472_discrete_device *int3472; 337 struct int3472_cldb cldb; 338 int ret; 339 340 ret = skl_int3472_fill_cldb(adev, &cldb); 341 if (ret) { 342 dev_err(&pdev->dev, "Couldn't fill CLDB structure\n"); 343 return ret; 344 } 345 346 if (cldb.control_logic_type != 1) { 347 dev_err(&pdev->dev, "Unsupported control logic type %u\n", 348 cldb.control_logic_type); 349 return -EINVAL; 350 } 351 352 /* Max num GPIOs we've seen plus a terminator */ 353 int3472 = devm_kzalloc(&pdev->dev, struct_size(int3472, gpios.table, 354 INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL); 355 if (!int3472) 356 return -ENOMEM; 357 358 int3472->adev = adev; 359 int3472->dev = &pdev->dev; 360 platform_set_drvdata(pdev, int3472); 361 362 ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor, 363 &int3472->sensor_name); 364 if (ret) 365 return ret; 366 367 /* 368 * Initialising this list means we can call gpiod_remove_lookup_table() 369 * in failure paths without issue. 370 */ 371 INIT_LIST_HEAD(&int3472->gpios.list); 372 373 ret = skl_int3472_parse_crs(int3472); 374 if (ret) { 375 skl_int3472_discrete_remove(pdev); 376 return ret; 377 } 378 379 acpi_dev_clear_dependencies(adev); 380 return 0; 381 } 382 383 static const struct acpi_device_id int3472_device_id[] = { 384 { "INT3472", 0 }, 385 { } 386 }; 387 MODULE_DEVICE_TABLE(acpi, int3472_device_id); 388 389 static struct platform_driver int3472_discrete = { 390 .driver = { 391 .name = "int3472-discrete", 392 .acpi_match_table = int3472_device_id, 393 }, 394 .probe = skl_int3472_discrete_probe, 395 .remove = skl_int3472_discrete_remove, 396 }; 397 module_platform_driver(int3472_discrete); 398 399 MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Discrete Device Driver"); 400 MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>"); 401 MODULE_LICENSE("GPL v2"); 402