1 // SPDX-License-Identifier: GPL-2.0 2 /* Author: Dan Scally <djrscally@gmail.com> */ 3 4 #include <linux/acpi.h> 5 #include <linux/bitfield.h> 6 #include <linux/device.h> 7 #include <linux/gpio/consumer.h> 8 #include <linux/gpio/machine.h> 9 #include <linux/i2c.h> 10 #include <linux/kernel.h> 11 #include <linux/module.h> 12 #include <linux/overflow.h> 13 #include <linux/platform_device.h> 14 #include <linux/string_choices.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 #define INT3472_GPIO_DSM_TYPE GENMASK(7, 0) 31 #define INT3472_GPIO_DSM_PIN GENMASK(15, 8) 32 #define INT3472_GPIO_DSM_SENSOR_ON_VAL GENMASK(31, 24) 33 34 /* 35 * 822ace8f-2814-4174-a56b-5f029fe079ee 36 * This _DSM GUID returns a string from the sensor device, which acts as a 37 * module identifier. 38 */ 39 static const guid_t cio2_sensor_module_guid = 40 GUID_INIT(0x822ace8f, 0x2814, 0x4174, 41 0xa5, 0x6b, 0x5f, 0x02, 0x9f, 0xe0, 0x79, 0xee); 42 43 static void skl_int3472_log_sensor_module_name(struct int3472_discrete_device *int3472) 44 { 45 union acpi_object *obj; 46 47 obj = acpi_evaluate_dsm_typed(int3472->sensor->handle, 48 &cio2_sensor_module_guid, 0x00, 49 0x01, NULL, ACPI_TYPE_STRING); 50 if (obj) { 51 dev_dbg(int3472->dev, "Sensor module id: '%s'\n", obj->string.pointer); 52 ACPI_FREE(obj); 53 } 54 } 55 56 static int skl_int3472_fill_gpiod_lookup(struct gpiod_lookup *table_entry, 57 struct acpi_resource_gpio *agpio, 58 const char *func, u32 polarity) 59 { 60 char *path = agpio->resource_source.string_ptr; 61 struct acpi_device *adev; 62 acpi_handle handle; 63 acpi_status status; 64 65 status = acpi_get_handle(NULL, path, &handle); 66 if (ACPI_FAILURE(status)) 67 return -EINVAL; 68 69 adev = acpi_fetch_acpi_dev(handle); 70 if (!adev) 71 return -ENODEV; 72 73 *table_entry = GPIO_LOOKUP(acpi_dev_name(adev), agpio->pin_table[0], func, polarity); 74 75 return 0; 76 } 77 78 static int skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device *int3472, 79 struct acpi_resource_gpio *agpio, 80 const char *func, u32 polarity) 81 { 82 int ret; 83 84 if (int3472->n_sensor_gpios >= INT3472_MAX_SENSOR_GPIOS) { 85 dev_warn(int3472->dev, "Too many GPIOs mapped\n"); 86 return -EINVAL; 87 } 88 89 ret = skl_int3472_fill_gpiod_lookup(&int3472->gpios.table[int3472->n_sensor_gpios], 90 agpio, func, polarity); 91 if (ret) 92 return ret; 93 94 int3472->n_sensor_gpios++; 95 96 return 0; 97 } 98 99 /* This should *really* only be used when there's no other way... */ 100 static struct gpio_desc * 101 skl_int3472_gpiod_get_from_temp_lookup(struct int3472_discrete_device *int3472, 102 struct acpi_resource_gpio *agpio, 103 const char *func, u32 polarity) 104 { 105 struct gpio_desc *desc; 106 int ret; 107 108 struct gpiod_lookup_table *lookup __free(kfree) = 109 kzalloc(struct_size(lookup, table, 2), GFP_KERNEL); 110 if (!lookup) 111 return ERR_PTR(-ENOMEM); 112 113 lookup->dev_id = dev_name(int3472->dev); 114 ret = skl_int3472_fill_gpiod_lookup(&lookup->table[0], agpio, func, polarity); 115 if (ret) 116 return ERR_PTR(ret); 117 118 gpiod_add_lookup_table(lookup); 119 desc = devm_gpiod_get(int3472->dev, func, GPIOD_OUT_LOW); 120 gpiod_remove_lookup_table(lookup); 121 122 return desc; 123 } 124 125 static void int3472_get_func_and_polarity(u8 type, const char **func, u32 *polarity) 126 { 127 switch (type) { 128 case INT3472_GPIO_TYPE_RESET: 129 *func = "reset"; 130 *polarity = GPIO_ACTIVE_LOW; 131 break; 132 case INT3472_GPIO_TYPE_POWERDOWN: 133 *func = "powerdown"; 134 *polarity = GPIO_ACTIVE_LOW; 135 break; 136 case INT3472_GPIO_TYPE_CLK_ENABLE: 137 *func = "clk-enable"; 138 *polarity = GPIO_ACTIVE_HIGH; 139 break; 140 case INT3472_GPIO_TYPE_PRIVACY_LED: 141 *func = "privacy-led"; 142 *polarity = GPIO_ACTIVE_HIGH; 143 break; 144 case INT3472_GPIO_TYPE_POWER_ENABLE: 145 *func = "power-enable"; 146 *polarity = GPIO_ACTIVE_HIGH; 147 break; 148 default: 149 *func = "unknown"; 150 *polarity = GPIO_ACTIVE_HIGH; 151 break; 152 } 153 } 154 155 /** 156 * skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor 157 * @ares: A pointer to a &struct acpi_resource 158 * @data: A pointer to a &struct int3472_discrete_device 159 * 160 * This function handles GPIO resources that are against an INT3472 161 * ACPI device, by checking the value of the corresponding _DSM entry. 162 * This will return a 32bit int, where the lowest byte represents the 163 * function of the GPIO pin: 164 * 165 * 0x00 Reset 166 * 0x01 Power down 167 * 0x0b Power enable 168 * 0x0c Clock enable 169 * 0x0d Privacy LED 170 * 171 * There are some known platform specific quirks where that does not quite 172 * hold up; for example where a pin with type 0x01 (Power down) is mapped to 173 * a sensor pin that performs a reset function or entries in _CRS and _DSM that 174 * do not actually correspond to a physical connection. These will be handled 175 * by the mapping sub-functions. 176 * 177 * GPIOs will either be mapped directly to the sensor device or else used 178 * to create clocks and regulators via the usual frameworks. 179 * 180 * Return: 181 * * 1 - Continue the loop without adding a copy of the resource to 182 * * the list passed to acpi_dev_get_resources() 183 * * 0 - Continue the loop after adding a copy of the resource to 184 * * the list passed to acpi_dev_get_resources() 185 * * -errno - Error, break loop 186 */ 187 static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares, 188 void *data) 189 { 190 struct int3472_discrete_device *int3472 = data; 191 struct acpi_resource_gpio *agpio; 192 u8 active_value, pin, type; 193 union acpi_object *obj; 194 struct gpio_desc *gpio; 195 const char *err_msg; 196 const char *func; 197 u32 polarity; 198 int ret; 199 200 if (!acpi_gpio_get_io_resource(ares, &agpio)) 201 return 1; 202 203 /* 204 * ngpios + 2 because the index of this _DSM function is 1-based and 205 * the first function is just a count. 206 */ 207 obj = acpi_evaluate_dsm_typed(int3472->adev->handle, 208 &int3472_gpio_guid, 0x00, 209 int3472->ngpios + 2, 210 NULL, ACPI_TYPE_INTEGER); 211 212 if (!obj) { 213 dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n", 214 agpio->pin_table[0]); 215 return 1; 216 } 217 218 type = FIELD_GET(INT3472_GPIO_DSM_TYPE, obj->integer.value); 219 220 int3472_get_func_and_polarity(type, &func, &polarity); 221 222 pin = FIELD_GET(INT3472_GPIO_DSM_PIN, obj->integer.value); 223 /* Pin field is not really used under Windows and wraps around at 8 bits */ 224 if (pin != (agpio->pin_table[0] & 0xff)) 225 dev_dbg(int3472->dev, FW_BUG "%s %s pin number mismatch _DSM %d resource %d\n", 226 func, agpio->resource_source.string_ptr, pin, agpio->pin_table[0]); 227 228 active_value = FIELD_GET(INT3472_GPIO_DSM_SENSOR_ON_VAL, obj->integer.value); 229 if (!active_value) 230 polarity ^= GPIO_ACTIVE_LOW; 231 232 dev_dbg(int3472->dev, "%s %s pin %d active-%s\n", func, 233 agpio->resource_source.string_ptr, agpio->pin_table[0], 234 str_high_low(polarity == GPIO_ACTIVE_HIGH)); 235 236 switch (type) { 237 case INT3472_GPIO_TYPE_RESET: 238 case INT3472_GPIO_TYPE_POWERDOWN: 239 ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, func, polarity); 240 if (ret) 241 err_msg = "Failed to map GPIO pin to sensor\n"; 242 243 break; 244 case INT3472_GPIO_TYPE_CLK_ENABLE: 245 case INT3472_GPIO_TYPE_PRIVACY_LED: 246 case INT3472_GPIO_TYPE_POWER_ENABLE: 247 gpio = skl_int3472_gpiod_get_from_temp_lookup(int3472, agpio, func, polarity); 248 if (IS_ERR(gpio)) { 249 ret = PTR_ERR(gpio); 250 err_msg = "Failed to get GPIO\n"; 251 break; 252 } 253 254 switch (type) { 255 case INT3472_GPIO_TYPE_CLK_ENABLE: 256 ret = skl_int3472_register_gpio_clock(int3472, gpio); 257 if (ret) 258 err_msg = "Failed to register clock\n"; 259 260 break; 261 case INT3472_GPIO_TYPE_PRIVACY_LED: 262 ret = skl_int3472_register_pled(int3472, gpio); 263 if (ret) 264 err_msg = "Failed to register LED\n"; 265 266 break; 267 case INT3472_GPIO_TYPE_POWER_ENABLE: 268 ret = skl_int3472_register_regulator(int3472, gpio); 269 if (ret) 270 err_msg = "Failed to map regulator to sensor\n"; 271 272 break; 273 default: /* Never reached */ 274 ret = -EINVAL; 275 break; 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 /* Tell acpi_dev_get_resources() to not make a copy of the resource */ 293 return 1; 294 } 295 296 static int skl_int3472_parse_crs(struct int3472_discrete_device *int3472) 297 { 298 LIST_HEAD(resource_list); 299 int ret; 300 301 skl_int3472_log_sensor_module_name(int3472); 302 303 ret = acpi_dev_get_resources(int3472->adev, &resource_list, 304 skl_int3472_handle_gpio_resources, 305 int3472); 306 if (ret < 0) 307 return ret; 308 309 acpi_dev_free_resource_list(&resource_list); 310 311 /* Register _DSM based clock (no-op if a GPIO clock was already registered) */ 312 ret = skl_int3472_register_dsm_clock(int3472); 313 if (ret < 0) 314 return ret; 315 316 int3472->gpios.dev_id = int3472->sensor_name; 317 gpiod_add_lookup_table(&int3472->gpios); 318 319 return 0; 320 } 321 322 static void skl_int3472_discrete_remove(struct platform_device *pdev) 323 { 324 struct int3472_discrete_device *int3472 = platform_get_drvdata(pdev); 325 326 gpiod_remove_lookup_table(&int3472->gpios); 327 328 skl_int3472_unregister_clock(int3472); 329 skl_int3472_unregister_pled(int3472); 330 skl_int3472_unregister_regulator(int3472); 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 if (!adev) 341 return -ENODEV; 342 343 ret = skl_int3472_fill_cldb(adev, &cldb); 344 if (ret) { 345 dev_err(&pdev->dev, "Couldn't fill CLDB structure\n"); 346 return ret; 347 } 348 349 if (cldb.control_logic_type != 1) { 350 dev_err(&pdev->dev, "Unsupported control logic type %u\n", 351 cldb.control_logic_type); 352 return -EINVAL; 353 } 354 355 /* Max num GPIOs we've seen plus a terminator */ 356 int3472 = devm_kzalloc(&pdev->dev, struct_size(int3472, gpios.table, 357 INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL); 358 if (!int3472) 359 return -ENOMEM; 360 361 int3472->adev = adev; 362 int3472->dev = &pdev->dev; 363 platform_set_drvdata(pdev, int3472); 364 int3472->clock.imgclk_index = cldb.clock_source; 365 366 ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor, 367 &int3472->sensor_name); 368 if (ret) 369 return ret; 370 371 /* 372 * Initialising this list means we can call gpiod_remove_lookup_table() 373 * in failure paths without issue. 374 */ 375 INIT_LIST_HEAD(&int3472->gpios.list); 376 377 ret = skl_int3472_parse_crs(int3472); 378 if (ret) { 379 skl_int3472_discrete_remove(pdev); 380 return ret; 381 } 382 383 acpi_dev_clear_dependencies(adev); 384 return 0; 385 } 386 387 static const struct acpi_device_id int3472_device_id[] = { 388 { "INT3472", 0 }, 389 { } 390 }; 391 MODULE_DEVICE_TABLE(acpi, int3472_device_id); 392 393 static struct platform_driver int3472_discrete = { 394 .driver = { 395 .name = "int3472-discrete", 396 .acpi_match_table = int3472_device_id, 397 }, 398 .probe = skl_int3472_discrete_probe, 399 .remove = skl_int3472_discrete_remove, 400 }; 401 module_platform_driver(int3472_discrete); 402 403 MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Discrete Device Driver"); 404 MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>"); 405 MODULE_LICENSE("GPL v2"); 406