1 // SPDX-License-Identifier: GPL-2.0 2 /* Author: Dan Scally <djrscally@gmail.com> */ 3 4 #include <linux/acpi.h> 5 #include <linux/clkdev.h> 6 #include <linux/clk-provider.h> 7 #include <linux/device.h> 8 #include <linux/gpio/consumer.h> 9 #include <linux/gpio/machine.h> 10 #include <linux/i2c.h> 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/overflow.h> 14 #include <linux/platform_device.h> 15 #include <linux/uuid.h> 16 17 #include "common.h" 18 19 /* 20 * 79234640-9e10-4fea-a5c1-b5aa8b19756f 21 * This _DSM GUID returns information about the GPIO lines mapped to a 22 * discrete INT3472 device. Function number 1 returns a count of the GPIO 23 * lines that are mapped. Subsequent functions return 32 bit ints encoding 24 * information about the GPIO line, including its purpose. 25 */ 26 static const guid_t int3472_gpio_guid = 27 GUID_INIT(0x79234640, 0x9e10, 0x4fea, 28 0xa5, 0xc1, 0xb5, 0xaa, 0x8b, 0x19, 0x75, 0x6f); 29 30 /* 31 * 822ace8f-2814-4174-a56b-5f029fe079ee 32 * This _DSM GUID returns a string from the sensor device, which acts as a 33 * module identifier. 34 */ 35 static const guid_t cio2_sensor_module_guid = 36 GUID_INIT(0x822ace8f, 0x2814, 0x4174, 37 0xa5, 0x6b, 0x5f, 0x02, 0x9f, 0xe0, 0x79, 0xee); 38 39 /* 40 * Here follows platform specific mapping information that we can pass to 41 * the functions mapping resources to the sensors. Where the sensors have 42 * a power enable pin defined in DSDT we need to provide a supply name so 43 * the sensor drivers can find the regulator. The device name will be derived 44 * from the sensor's ACPI device within the code. Optionally, we can provide a 45 * NULL terminated array of function name mappings to deal with any platform 46 * specific deviations from the documented behaviour of GPIOs. 47 * 48 * Map a GPIO function name to NULL to prevent the driver from mapping that 49 * GPIO at all. 50 */ 51 52 static const struct int3472_gpio_function_remap ov2680_gpio_function_remaps[] = { 53 { "reset", NULL }, 54 { "powerdown", "reset" }, 55 { } 56 }; 57 58 static const struct int3472_sensor_config int3472_sensor_configs[] = { 59 /* Lenovo Miix 510-12ISK - OV2680, Front */ 60 { "GNDF140809R", { 0 }, ov2680_gpio_function_remaps }, 61 /* Lenovo Miix 510-12ISK - OV5648, Rear */ 62 { "GEFF150023R", REGULATOR_SUPPLY("avdd", NULL), NULL }, 63 /* Surface Go 1&2 - OV5693, Front */ 64 { "YHCU", REGULATOR_SUPPLY("avdd", NULL), NULL }, 65 }; 66 67 static const struct int3472_sensor_config * 68 skl_int3472_get_sensor_module_config(struct int3472_discrete_device *int3472) 69 { 70 union acpi_object *obj; 71 unsigned int i; 72 73 obj = acpi_evaluate_dsm_typed(int3472->sensor->handle, 74 &cio2_sensor_module_guid, 0x00, 75 0x01, NULL, ACPI_TYPE_STRING); 76 77 if (!obj) { 78 dev_err(int3472->dev, 79 "Failed to get sensor module string from _DSM\n"); 80 return ERR_PTR(-ENODEV); 81 } 82 83 if (obj->string.type != ACPI_TYPE_STRING) { 84 dev_err(int3472->dev, 85 "Sensor _DSM returned a non-string value\n"); 86 87 ACPI_FREE(obj); 88 return ERR_PTR(-EINVAL); 89 } 90 91 for (i = 0; i < ARRAY_SIZE(int3472_sensor_configs); i++) { 92 if (!strcmp(int3472_sensor_configs[i].sensor_module_name, 93 obj->string.pointer)) 94 break; 95 } 96 97 ACPI_FREE(obj); 98 99 if (i >= ARRAY_SIZE(int3472_sensor_configs)) 100 return ERR_PTR(-EINVAL); 101 102 return &int3472_sensor_configs[i]; 103 } 104 105 static int skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device *int3472, 106 struct acpi_resource_gpio *agpio, 107 const char *func, u32 polarity) 108 { 109 const struct int3472_sensor_config *sensor_config; 110 char *path = agpio->resource_source.string_ptr; 111 struct gpiod_lookup *table_entry; 112 struct acpi_device *adev; 113 acpi_handle handle; 114 acpi_status status; 115 116 if (int3472->n_sensor_gpios >= INT3472_MAX_SENSOR_GPIOS) { 117 dev_warn(int3472->dev, "Too many GPIOs mapped\n"); 118 return -EINVAL; 119 } 120 121 sensor_config = int3472->sensor_config; 122 if (!IS_ERR(sensor_config) && sensor_config->function_maps) { 123 const struct int3472_gpio_function_remap *remap; 124 125 for (remap = sensor_config->function_maps; remap->documented; remap++) { 126 if (!strcmp(func, remap->documented)) { 127 func = remap->actual; 128 break; 129 } 130 } 131 } 132 133 /* Functions mapped to NULL should not be mapped to the sensor */ 134 if (!func) 135 return 0; 136 137 status = acpi_get_handle(NULL, path, &handle); 138 if (ACPI_FAILURE(status)) 139 return -EINVAL; 140 141 adev = acpi_fetch_acpi_dev(handle); 142 if (!adev) 143 return -ENODEV; 144 145 table_entry = &int3472->gpios.table[int3472->n_sensor_gpios]; 146 table_entry->key = acpi_dev_name(adev); 147 table_entry->chip_hwnum = agpio->pin_table[0]; 148 table_entry->con_id = func; 149 table_entry->idx = 0; 150 table_entry->flags = polarity; 151 152 int3472->n_sensor_gpios++; 153 154 return 0; 155 } 156 157 static int skl_int3472_map_gpio_to_clk(struct int3472_discrete_device *int3472, 158 struct acpi_resource_gpio *agpio, u8 type) 159 { 160 char *path = agpio->resource_source.string_ptr; 161 u16 pin = agpio->pin_table[0]; 162 struct gpio_desc *gpio; 163 164 switch (type) { 165 case INT3472_GPIO_TYPE_CLK_ENABLE: 166 gpio = acpi_get_and_request_gpiod(path, pin, "int3472,clk-enable"); 167 if (IS_ERR(gpio)) 168 return (PTR_ERR(gpio)); 169 170 int3472->clock.ena_gpio = gpio; 171 break; 172 case INT3472_GPIO_TYPE_PRIVACY_LED: 173 gpio = acpi_get_and_request_gpiod(path, pin, "int3472,privacy-led"); 174 if (IS_ERR(gpio)) 175 return (PTR_ERR(gpio)); 176 177 int3472->clock.led_gpio = gpio; 178 break; 179 default: 180 dev_err(int3472->dev, "Invalid GPIO type 0x%02x for clock\n", type); 181 break; 182 } 183 184 return 0; 185 } 186 187 /** 188 * skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor 189 * @ares: A pointer to a &struct acpi_resource 190 * @data: A pointer to a &struct int3472_discrete_device 191 * 192 * This function handles GPIO resources that are against an INT3472 193 * ACPI device, by checking the value of the corresponding _DSM entry. 194 * This will return a 32bit int, where the lowest byte represents the 195 * function of the GPIO pin: 196 * 197 * 0x00 Reset 198 * 0x01 Power down 199 * 0x0b Power enable 200 * 0x0c Clock enable 201 * 0x0d Privacy LED 202 * 203 * There are some known platform specific quirks where that does not quite 204 * hold up; for example where a pin with type 0x01 (Power down) is mapped to 205 * a sensor pin that performs a reset function or entries in _CRS and _DSM that 206 * do not actually correspond to a physical connection. These will be handled 207 * by the mapping sub-functions. 208 * 209 * GPIOs will either be mapped directly to the sensor device or else used 210 * to create clocks and regulators via the usual frameworks. 211 * 212 * Return: 213 * * 1 - To continue the loop 214 * * 0 - When all resources found are handled properly. 215 * * -EINVAL - If the resource is not a GPIO IO resource 216 * * -ENODEV - If the resource has no corresponding _DSM entry 217 * * -Other - Errors propagated from one of the sub-functions. 218 */ 219 static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares, 220 void *data) 221 { 222 struct int3472_discrete_device *int3472 = data; 223 struct acpi_resource_gpio *agpio; 224 union acpi_object *obj; 225 const char *err_msg; 226 int ret; 227 u8 type; 228 229 if (!acpi_gpio_get_io_resource(ares, &agpio)) 230 return 1; 231 232 /* 233 * ngpios + 2 because the index of this _DSM function is 1-based and 234 * the first function is just a count. 235 */ 236 obj = acpi_evaluate_dsm_typed(int3472->adev->handle, 237 &int3472_gpio_guid, 0x00, 238 int3472->ngpios + 2, 239 NULL, ACPI_TYPE_INTEGER); 240 241 if (!obj) { 242 dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n", 243 agpio->pin_table[0]); 244 return 1; 245 } 246 247 type = obj->integer.value & 0xff; 248 249 switch (type) { 250 case INT3472_GPIO_TYPE_RESET: 251 ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, "reset", 252 GPIO_ACTIVE_LOW); 253 if (ret) 254 err_msg = "Failed to map reset pin to sensor\n"; 255 256 break; 257 case INT3472_GPIO_TYPE_POWERDOWN: 258 ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, "powerdown", 259 GPIO_ACTIVE_LOW); 260 if (ret) 261 err_msg = "Failed to map powerdown pin to sensor\n"; 262 263 break; 264 case INT3472_GPIO_TYPE_CLK_ENABLE: 265 case INT3472_GPIO_TYPE_PRIVACY_LED: 266 ret = skl_int3472_map_gpio_to_clk(int3472, agpio, type); 267 if (ret) 268 err_msg = "Failed to map GPIO to clock\n"; 269 270 break; 271 case INT3472_GPIO_TYPE_POWER_ENABLE: 272 ret = skl_int3472_register_regulator(int3472, agpio); 273 if (ret) 274 err_msg = "Failed to map regulator to sensor\n"; 275 276 break; 277 default: 278 dev_warn(int3472->dev, 279 "GPIO type 0x%02x unknown; the sensor may not work\n", 280 type); 281 ret = 1; 282 break; 283 } 284 285 int3472->ngpios++; 286 ACPI_FREE(obj); 287 288 if (ret < 0) 289 return dev_err_probe(int3472->dev, ret, err_msg); 290 291 return ret; 292 } 293 294 static int skl_int3472_parse_crs(struct int3472_discrete_device *int3472) 295 { 296 LIST_HEAD(resource_list); 297 int ret; 298 299 /* 300 * No error check, because not having a sensor config is not necessarily 301 * a failure mode. 302 */ 303 int3472->sensor_config = skl_int3472_get_sensor_module_config(int3472); 304 305 ret = acpi_dev_get_resources(int3472->adev, &resource_list, 306 skl_int3472_handle_gpio_resources, 307 int3472); 308 if (ret < 0) 309 return ret; 310 311 acpi_dev_free_resource_list(&resource_list); 312 313 /* 314 * If we find no clock enable GPIO pin then the privacy LED won't work. 315 * We've never seen that situation, but it's possible. Warn the user so 316 * it's clear what's happened. 317 */ 318 if (int3472->clock.ena_gpio) { 319 ret = skl_int3472_register_clock(int3472); 320 if (ret) 321 return ret; 322 } else { 323 if (int3472->clock.led_gpio) 324 dev_warn(int3472->dev, 325 "No clk GPIO. The privacy LED won't work\n"); 326 } 327 328 int3472->gpios.dev_id = int3472->sensor_name; 329 gpiod_add_lookup_table(&int3472->gpios); 330 331 return 0; 332 } 333 334 static int skl_int3472_discrete_remove(struct platform_device *pdev) 335 { 336 struct int3472_discrete_device *int3472 = platform_get_drvdata(pdev); 337 338 gpiod_remove_lookup_table(&int3472->gpios); 339 340 if (int3472->clock.cl) 341 skl_int3472_unregister_clock(int3472); 342 343 gpiod_put(int3472->clock.ena_gpio); 344 gpiod_put(int3472->clock.led_gpio); 345 346 skl_int3472_unregister_regulator(int3472); 347 348 return 0; 349 } 350 351 static int skl_int3472_discrete_probe(struct platform_device *pdev) 352 { 353 struct acpi_device *adev = ACPI_COMPANION(&pdev->dev); 354 struct int3472_discrete_device *int3472; 355 struct int3472_cldb cldb; 356 int ret; 357 358 ret = skl_int3472_fill_cldb(adev, &cldb); 359 if (ret) { 360 dev_err(&pdev->dev, "Couldn't fill CLDB structure\n"); 361 return ret; 362 } 363 364 if (cldb.control_logic_type != 1) { 365 dev_err(&pdev->dev, "Unsupported control logic type %u\n", 366 cldb.control_logic_type); 367 return -EINVAL; 368 } 369 370 /* Max num GPIOs we've seen plus a terminator */ 371 int3472 = devm_kzalloc(&pdev->dev, struct_size(int3472, gpios.table, 372 INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL); 373 if (!int3472) 374 return -ENOMEM; 375 376 int3472->adev = adev; 377 int3472->dev = &pdev->dev; 378 platform_set_drvdata(pdev, int3472); 379 380 ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor, 381 &int3472->sensor_name); 382 if (ret) 383 return ret; 384 385 /* 386 * Initialising this list means we can call gpiod_remove_lookup_table() 387 * in failure paths without issue. 388 */ 389 INIT_LIST_HEAD(&int3472->gpios.list); 390 391 ret = skl_int3472_parse_crs(int3472); 392 if (ret) { 393 skl_int3472_discrete_remove(pdev); 394 return ret; 395 } 396 397 acpi_dev_clear_dependencies(adev); 398 return 0; 399 } 400 401 static const struct acpi_device_id int3472_device_id[] = { 402 { "INT3472", 0 }, 403 { } 404 }; 405 MODULE_DEVICE_TABLE(acpi, int3472_device_id); 406 407 static struct platform_driver int3472_discrete = { 408 .driver = { 409 .name = "int3472-discrete", 410 .acpi_match_table = int3472_device_id, 411 }, 412 .probe = skl_int3472_discrete_probe, 413 .remove = skl_int3472_discrete_remove, 414 }; 415 module_platform_driver(int3472_discrete); 416 417 MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Discrete Device Driver"); 418 MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>"); 419 MODULE_LICENSE("GPL v2"); 420