drivers/platform/x86/intel/int3472/discrete.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /* Author: Dan Scally <djrscally@gmail.com> */

 #include <linux/acpi.h>
 #include <linux/bitfield.h>
 #include <linux/device.h>
 #include <linux/gpio/consumer.h>
 #include <linux/gpio/machine.h>
 #include <linux/i2c.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/overflow.h>
 #include <linux/platform_device.h>
 #include <linux/uuid.h>

 #include "common.h"

 /*
  * 79234640-9e10-4fea-a5c1-b5aa8b19756f
  * This _DSM GUID returns information about the GPIO lines mapped to a
  * discrete INT3472 device. Function number 1 returns a count of the GPIO
  * lines that are mapped. Subsequent functions return 32 bit ints encoding
  * information about the GPIO line, including its purpose.
  */
 static const guid_t int3472_gpio_guid =
 	GUID_INIT(0x79234640, 0x9e10, 0x4fea,
 		  0xa5, 0xc1, 0xb5, 0xaa, 0x8b, 0x19, 0x75, 0x6f);

 #define INT3472_GPIO_DSM_TYPE				GENMASK(7, 0)
 #define INT3472_GPIO_DSM_PIN				GENMASK(15, 8)
 #define INT3472_GPIO_DSM_SENSOR_ON_VAL			GENMASK(31, 24)

 /*
  * 822ace8f-2814-4174-a56b-5f029fe079ee
  * This _DSM GUID returns a string from the sensor device, which acts as a
  * module identifier.
  */
 static const guid_t cio2_sensor_module_guid =
 	GUID_INIT(0x822ace8f, 0x2814, 0x4174,
 		  0xa5, 0x6b, 0x5f, 0x02, 0x9f, 0xe0, 0x79, 0xee);

 static void skl_int3472_log_sensor_module_name(struct int3472_discrete_device *int3472)
 {
 	union acpi_object *obj;

 	obj = acpi_evaluate_dsm_typed(int3472->sensor->handle,
 				      &cio2_sensor_module_guid, 0x00,
 				      0x01, NULL, ACPI_TYPE_STRING);
 	if (obj) {
 		dev_dbg(int3472->dev, "Sensor module id: '%s'\n", obj->string.pointer);
 		ACPI_FREE(obj);
 	}
 }

 static int skl_int3472_fill_gpiod_lookup(struct gpiod_lookup *table_entry,
 					 struct acpi_resource_gpio *agpio,
 					 const char *func, u32 polarity)
 {
 	char *path = agpio->resource_source.string_ptr;
 	struct acpi_device *adev;
 	acpi_handle handle;
 	acpi_status status;

 	status = acpi_get_handle(NULL, path, &handle);
 	if (ACPI_FAILURE(status))
 		return -EINVAL;

 	adev = acpi_fetch_acpi_dev(handle);
 	if (!adev)
 		return -ENODEV;

 	table_entry->key = acpi_dev_name(adev);
 	table_entry->chip_hwnum = agpio->pin_table[0];
 	table_entry->con_id = func;
 	table_entry->idx = 0;
 	table_entry->flags = polarity;

 	return 0;
 }

 static int skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device *int3472,
 					  struct acpi_resource_gpio *agpio,
 					  const char *func, u32 polarity)
 {
 	int ret;

 	if (int3472->n_sensor_gpios >= INT3472_MAX_SENSOR_GPIOS) {
 		dev_warn(int3472->dev, "Too many GPIOs mapped\n");
 		return -EINVAL;
 	}

 	ret = skl_int3472_fill_gpiod_lookup(&int3472->gpios.table[int3472->n_sensor_gpios],
 					    agpio, func, polarity);
 	if (ret)
 		return ret;

 	int3472->n_sensor_gpios++;

 	return 0;
 }

 /* This should *really* only be used when there's no other way... */
 static struct gpio_desc *
 skl_int3472_gpiod_get_from_temp_lookup(struct int3472_discrete_device *int3472,
 				       struct acpi_resource_gpio *agpio,
 				       const char *func, u32 polarity)
 {
 	struct gpio_desc *desc;
 	int ret;

 	struct gpiod_lookup_table *lookup __free(kfree) =
 			kzalloc(struct_size(lookup, table, 2), GFP_KERNEL);
 	if (!lookup)
 		return ERR_PTR(-ENOMEM);

 	lookup->dev_id = dev_name(int3472->dev);
 	ret = skl_int3472_fill_gpiod_lookup(&lookup->table[0], agpio, func, polarity);
 	if (ret)
 		return ERR_PTR(ret);

 	gpiod_add_lookup_table(lookup);
 	desc = devm_gpiod_get(int3472->dev, func, GPIOD_OUT_LOW);
 	gpiod_remove_lookup_table(lookup);

 	return desc;
 }

 static void int3472_get_func_and_polarity(u8 type, const char **func, u32 *polarity)
 {
 	switch (type) {
 	case INT3472_GPIO_TYPE_RESET:
 		*func = "reset";
 		*polarity = GPIO_ACTIVE_LOW;
 		break;
 	case INT3472_GPIO_TYPE_POWERDOWN:
 		*func = "powerdown";
 		*polarity = GPIO_ACTIVE_LOW;
 		break;
 	case INT3472_GPIO_TYPE_CLK_ENABLE:
 		*func = "clk-enable";
 		*polarity = GPIO_ACTIVE_HIGH;
 		break;
 	case INT3472_GPIO_TYPE_PRIVACY_LED:
 		*func = "privacy-led";
 		*polarity = GPIO_ACTIVE_HIGH;
 		break;
 	case INT3472_GPIO_TYPE_POWER_ENABLE:
 		*func = "power-enable";
 		*polarity = GPIO_ACTIVE_HIGH;
 		break;
 	default:
 		*func = "unknown";
 		*polarity = GPIO_ACTIVE_HIGH;
 		break;
 	}
 }

 /**
  * skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor
  * @ares: A pointer to a &struct acpi_resource
  * @data: A pointer to a &struct int3472_discrete_device
  *
  * This function handles GPIO resources that are against an INT3472
  * ACPI device, by checking the value of the corresponding _DSM entry.
  * This will return a 32bit int, where the lowest byte represents the
  * function of the GPIO pin:
  *
  * 0x00 Reset
  * 0x01 Power down
  * 0x0b Power enable
  * 0x0c Clock enable
  * 0x0d Privacy LED
  *
  * There are some known platform specific quirks where that does not quite
  * hold up; for example where a pin with type 0x01 (Power down) is mapped to
  * a sensor pin that performs a reset function or entries in _CRS and _DSM that
  * do not actually correspond to a physical connection. These will be handled
  * by the mapping sub-functions.
  *
  * GPIOs will either be mapped directly to the sensor device or else used
  * to create clocks and regulators via the usual frameworks.
  *
  * Return:
  * * 1		- To continue the loop
  * * 0		- When all resources found are handled properly.
  * * -EINVAL	- If the resource is not a GPIO IO resource
  * * -ENODEV	- If the resource has no corresponding _DSM entry
  * * -Other	- Errors propagated from one of the sub-functions.
  */
 static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
 					     void *data)
 {
 	struct int3472_discrete_device *int3472 = data;
 	struct acpi_resource_gpio *agpio;
 	u8 active_value, pin, type;
 	union acpi_object *obj;
 	struct gpio_desc *gpio;
 	const char *err_msg;
 	const char *func;
 	u32 polarity;
 	int ret;

 	if (!acpi_gpio_get_io_resource(ares, &agpio))
 		return 1;

 	/*
 	 * ngpios + 2 because the index of this _DSM function is 1-based and
 	 * the first function is just a count.
 	 */
 	obj = acpi_evaluate_dsm_typed(int3472->adev->handle,
 				      &int3472_gpio_guid, 0x00,
 				      int3472->ngpios + 2,
 				      NULL, ACPI_TYPE_INTEGER);

 	if (!obj) {
 		dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n",
 			 agpio->pin_table[0]);
 		return 1;
 	}

 	type = FIELD_GET(INT3472_GPIO_DSM_TYPE, obj->integer.value);

 	int3472_get_func_and_polarity(type, &func, &polarity);

 	pin = FIELD_GET(INT3472_GPIO_DSM_PIN, obj->integer.value);
 	if (pin != agpio->pin_table[0])
 		dev_warn(int3472->dev, "%s %s pin number mismatch _DSM %d resource %d\n",
 			 func, agpio->resource_source.string_ptr, pin,
 			 agpio->pin_table[0]);

 	active_value = FIELD_GET(INT3472_GPIO_DSM_SENSOR_ON_VAL, obj->integer.value);
 	if (!active_value)
 		polarity ^= GPIO_ACTIVE_LOW;

 	dev_dbg(int3472->dev, "%s %s pin %d active-%s\n", func,
 		agpio->resource_source.string_ptr, agpio->pin_table[0],
 		(polarity == GPIO_ACTIVE_HIGH) ? "high" : "low");

 	switch (type) {
 	case INT3472_GPIO_TYPE_RESET:
 	case INT3472_GPIO_TYPE_POWERDOWN:
 		ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, func, polarity);
 		if (ret)
 			err_msg = "Failed to map GPIO pin to sensor\n";

 		break;
 	case INT3472_GPIO_TYPE_CLK_ENABLE:
 	case INT3472_GPIO_TYPE_PRIVACY_LED:
 	case INT3472_GPIO_TYPE_POWER_ENABLE:
 		gpio = skl_int3472_gpiod_get_from_temp_lookup(int3472, agpio, func, polarity);
 		if (IS_ERR(gpio)) {
 			ret = PTR_ERR(gpio);
 			err_msg = "Failed to get GPIO\n";
 			break;
 		}

 		switch (type) {
 		case INT3472_GPIO_TYPE_CLK_ENABLE:
 			ret = skl_int3472_register_gpio_clock(int3472, gpio);
 			if (ret)
 				err_msg = "Failed to register clock\n";

 			break;
 		case INT3472_GPIO_TYPE_PRIVACY_LED:
 			ret = skl_int3472_register_pled(int3472, gpio);
 			if (ret)
 				err_msg = "Failed to register LED\n";

 			break;
 		case INT3472_GPIO_TYPE_POWER_ENABLE:
 			ret = skl_int3472_register_regulator(int3472, gpio);
 			if (ret)
 				err_msg = "Failed to map regulator to sensor\n";

 			break;
 		default: /* Never reached */
 			ret = -EINVAL;
 			break;
 		}
 		break;
 	default:
 		dev_warn(int3472->dev,
 			 "GPIO type 0x%02x unknown; the sensor may not work\n",
 			 type);
 		ret = 1;
 		break;
 	}

 	int3472->ngpios++;
 	ACPI_FREE(obj);

 	if (ret < 0)
 		return dev_err_probe(int3472->dev, ret, err_msg);

 	return ret;
 }

 static int skl_int3472_parse_crs(struct int3472_discrete_device *int3472)
 {
 	LIST_HEAD(resource_list);
 	int ret;

 	skl_int3472_log_sensor_module_name(int3472);

 	ret = acpi_dev_get_resources(int3472->adev, &resource_list,
 				     skl_int3472_handle_gpio_resources,
 				     int3472);
 	if (ret < 0)
 		return ret;

 	acpi_dev_free_resource_list(&resource_list);

 	/* Register _DSM based clock (no-op if a GPIO clock was already registered) */
 	ret = skl_int3472_register_dsm_clock(int3472);
 	if (ret < 0)
 		return ret;

 	int3472->gpios.dev_id = int3472->sensor_name;
 	gpiod_add_lookup_table(&int3472->gpios);

 	return 0;
 }

 static void skl_int3472_discrete_remove(struct platform_device *pdev)
 {
 	struct int3472_discrete_device *int3472 = platform_get_drvdata(pdev);

 	gpiod_remove_lookup_table(&int3472->gpios);

 	skl_int3472_unregister_clock(int3472);
 	skl_int3472_unregister_pled(int3472);
 	skl_int3472_unregister_regulator(int3472);
 }

 static int skl_int3472_discrete_probe(struct platform_device *pdev)
 {
 	struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
 	struct int3472_discrete_device *int3472;
 	struct int3472_cldb cldb;
 	int ret;

 	ret = skl_int3472_fill_cldb(adev, &cldb);
 	if (ret) {
 		dev_err(&pdev->dev, "Couldn't fill CLDB structure\n");
 		return ret;
 	}

 	if (cldb.control_logic_type != 1) {
 		dev_err(&pdev->dev, "Unsupported control logic type %u\n",
 			cldb.control_logic_type);
 		return -EINVAL;
 	}

 	/* Max num GPIOs we've seen plus a terminator */
 	int3472 = devm_kzalloc(&pdev->dev, struct_size(int3472, gpios.table,
 			       INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL);
 	if (!int3472)
 		return -ENOMEM;

 	int3472->adev = adev;
 	int3472->dev = &pdev->dev;
 	platform_set_drvdata(pdev, int3472);
 	int3472->clock.imgclk_index = cldb.clock_source;

 	ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor,
 						   &int3472->sensor_name);
 	if (ret)
 		return ret;

 	/*
 	 * Initialising this list means we can call gpiod_remove_lookup_table()
 	 * in failure paths without issue.
 	 */
 	INIT_LIST_HEAD(&int3472->gpios.list);

 	ret = skl_int3472_parse_crs(int3472);
 	if (ret) {
 		skl_int3472_discrete_remove(pdev);
 		return ret;
 	}

 	acpi_dev_clear_dependencies(adev);
 	return 0;
 }

 static const struct acpi_device_id int3472_device_id[] = {
 	{ "INT3472", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(acpi, int3472_device_id);

 static struct platform_driver int3472_discrete = {
 	.driver = {
 		.name = "int3472-discrete",
 		.acpi_match_table = int3472_device_id,
 	},
 	.probe = skl_int3472_discrete_probe,
 	.remove_new = skl_int3472_discrete_remove,
 };
 module_platform_driver(int3472_discrete);

 MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Discrete Device Driver");
 MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0
	/* Author: Dan Scally <djrscally@gmail.com> */

	#include <linux/acpi.h>
	#include <linux/bitfield.h>
	#include <linux/device.h>
	#include <linux/gpio/consumer.h>
	#include <linux/gpio/machine.h>
	#include <linux/i2c.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/overflow.h>
	#include <linux/platform_device.h>
	#include <linux/uuid.h>

	#include "common.h"

	/*
	* 79234640-9e10-4fea-a5c1-b5aa8b19756f
	* This _DSM GUID returns information about the GPIO lines mapped to a
	* discrete INT3472 device. Function number 1 returns a count of the GPIO
	* lines that are mapped. Subsequent functions return 32 bit ints encoding
	* information about the GPIO line, including its purpose.
	*/
	static const guid_t int3472_gpio_guid =
	GUID_INIT(0x79234640, 0x9e10, 0x4fea,
	0xa5, 0xc1, 0xb5, 0xaa, 0x8b, 0x19, 0x75, 0x6f);

	#define INT3472_GPIO_DSM_TYPE GENMASK(7, 0)
	#define INT3472_GPIO_DSM_PIN GENMASK(15, 8)
	#define INT3472_GPIO_DSM_SENSOR_ON_VAL GENMASK(31, 24)

	/*
	* 822ace8f-2814-4174-a56b-5f029fe079ee
	* This _DSM GUID returns a string from the sensor device, which acts as a
	* module identifier.
	*/
	static const guid_t cio2_sensor_module_guid =
	GUID_INIT(0x822ace8f, 0x2814, 0x4174,
	0xa5, 0x6b, 0x5f, 0x02, 0x9f, 0xe0, 0x79, 0xee);

	static void skl_int3472_log_sensor_module_name(struct int3472_discrete_device *int3472)
	{
	union acpi_object *obj;

	obj = acpi_evaluate_dsm_typed(int3472->sensor->handle,
	&cio2_sensor_module_guid, 0x00,
	0x01, NULL, ACPI_TYPE_STRING);
	if (obj) {
	dev_dbg(int3472->dev, "Sensor module id: '%s'\n", obj->string.pointer);
	ACPI_FREE(obj);
	}
	}

	static int skl_int3472_fill_gpiod_lookup(struct gpiod_lookup *table_entry,
	struct acpi_resource_gpio *agpio,
	const char *func, u32 polarity)
	{
	char *path = agpio->resource_source.string_ptr;
	struct acpi_device *adev;
	acpi_handle handle;
	acpi_status status;

	status = acpi_get_handle(NULL, path, &handle);
	if (ACPI_FAILURE(status))
	return -EINVAL;

	adev = acpi_fetch_acpi_dev(handle);
	if (!adev)
	return -ENODEV;

	table_entry->key = acpi_dev_name(adev);
	table_entry->chip_hwnum = agpio->pin_table[0];
	table_entry->con_id = func;
	table_entry->idx = 0;
	table_entry->flags = polarity;

	return 0;
	}

	static int skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device *int3472,
	struct acpi_resource_gpio *agpio,
	const char *func, u32 polarity)
	{
	int ret;

	if (int3472->n_sensor_gpios >= INT3472_MAX_SENSOR_GPIOS) {
	dev_warn(int3472->dev, "Too many GPIOs mapped\n");
	return -EINVAL;
	}

	ret = skl_int3472_fill_gpiod_lookup(&int3472->gpios.table[int3472->n_sensor_gpios],
	agpio, func, polarity);
	if (ret)
	return ret;

	int3472->n_sensor_gpios++;

	return 0;
	}

	/* This should really only be used when there's no other way... */
	static struct gpio_desc *
	skl_int3472_gpiod_get_from_temp_lookup(struct int3472_discrete_device *int3472,
	struct acpi_resource_gpio *agpio,
	const char *func, u32 polarity)
	{
	struct gpio_desc *desc;
	int ret;

	struct gpiod_lookup_table *lookup __free(kfree) =
	kzalloc(struct_size(lookup, table, 2), GFP_KERNEL);
	if (!lookup)
	return ERR_PTR(-ENOMEM);

	lookup->dev_id = dev_name(int3472->dev);
	ret = skl_int3472_fill_gpiod_lookup(&lookup->table[0], agpio, func, polarity);
	if (ret)
	return ERR_PTR(ret);

	gpiod_add_lookup_table(lookup);
	desc = devm_gpiod_get(int3472->dev, func, GPIOD_OUT_LOW);
	gpiod_remove_lookup_table(lookup);

	return desc;
	}

	static void int3472_get_func_and_polarity(u8 type, const char *func, u32 polarity)
	{
	switch (type) {
	case INT3472_GPIO_TYPE_RESET:
	*func = "reset";
	*polarity = GPIO_ACTIVE_LOW;
	break;
	case INT3472_GPIO_TYPE_POWERDOWN:
	*func = "powerdown";
	*polarity = GPIO_ACTIVE_LOW;
	break;
	case INT3472_GPIO_TYPE_CLK_ENABLE:
	*func = "clk-enable";
	*polarity = GPIO_ACTIVE_HIGH;
	break;
	case INT3472_GPIO_TYPE_PRIVACY_LED:
	*func = "privacy-led";
	*polarity = GPIO_ACTIVE_HIGH;
	break;
	case INT3472_GPIO_TYPE_POWER_ENABLE:
	*func = "power-enable";
	*polarity = GPIO_ACTIVE_HIGH;
	break;
	default:
	*func = "unknown";
	*polarity = GPIO_ACTIVE_HIGH;
	break;
	}
	}

	/**
	* skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor
	* @ares: A pointer to a &struct acpi_resource
	* @data: A pointer to a &struct int3472_discrete_device
	*
	* This function handles GPIO resources that are against an INT3472
	* ACPI device, by checking the value of the corresponding _DSM entry.
	* This will return a 32bit int, where the lowest byte represents the
	* function of the GPIO pin:
	*
	* 0x00 Reset
	* 0x01 Power down
	* 0x0b Power enable
	* 0x0c Clock enable
	* 0x0d Privacy LED
	*
	* There are some known platform specific quirks where that does not quite
	* hold up; for example where a pin with type 0x01 (Power down) is mapped to
	* a sensor pin that performs a reset function or entries in _CRS and _DSM that
	* do not actually correspond to a physical connection. These will be handled
	* by the mapping sub-functions.
	*
	* GPIOs will either be mapped directly to the sensor device or else used
	* to create clocks and regulators via the usual frameworks.
	*
	* Return:
	* * 1 - To continue the loop
	* * 0 - When all resources found are handled properly.
	* * -EINVAL - If the resource is not a GPIO IO resource
	* * -ENODEV - If the resource has no corresponding _DSM entry
	* * -Other - Errors propagated from one of the sub-functions.
	*/
	static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
	void *data)
	{
	struct int3472_discrete_device *int3472 = data;
	struct acpi_resource_gpio *agpio;
	u8 active_value, pin, type;
	union acpi_object *obj;
	struct gpio_desc *gpio;
	const char *err_msg;
	const char *func;
	u32 polarity;
	int ret;

	if (!acpi_gpio_get_io_resource(ares, &agpio))
	return 1;

	/*
	* ngpios + 2 because the index of this _DSM function is 1-based and
	* the first function is just a count.
	*/
	obj = acpi_evaluate_dsm_typed(int3472->adev->handle,
	&int3472_gpio_guid, 0x00,
	int3472->ngpios + 2,
	NULL, ACPI_TYPE_INTEGER);

	if (!obj) {
	dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n",
	agpio->pin_table[0]);
	return 1;
	}

	type = FIELD_GET(INT3472_GPIO_DSM_TYPE, obj->integer.value);

	int3472_get_func_and_polarity(type, &func, &polarity);

	pin = FIELD_GET(INT3472_GPIO_DSM_PIN, obj->integer.value);
	if (pin != agpio->pin_table[0])
	dev_warn(int3472->dev, "%s %s pin number mismatch _DSM %d resource %d\n",
	func, agpio->resource_source.string_ptr, pin,
	agpio->pin_table[0]);

	active_value = FIELD_GET(INT3472_GPIO_DSM_SENSOR_ON_VAL, obj->integer.value);
	if (!active_value)
	polarity ^= GPIO_ACTIVE_LOW;

	dev_dbg(int3472->dev, "%s %s pin %d active-%s\n", func,
	agpio->resource_source.string_ptr, agpio->pin_table[0],
	(polarity == GPIO_ACTIVE_HIGH) ? "high" : "low");

	switch (type) {
	case INT3472_GPIO_TYPE_RESET:
	case INT3472_GPIO_TYPE_POWERDOWN:
	ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, func, polarity);
	if (ret)
	err_msg = "Failed to map GPIO pin to sensor\n";

	break;
	case INT3472_GPIO_TYPE_CLK_ENABLE:
	case INT3472_GPIO_TYPE_PRIVACY_LED:
	case INT3472_GPIO_TYPE_POWER_ENABLE:
	gpio = skl_int3472_gpiod_get_from_temp_lookup(int3472, agpio, func, polarity);
	if (IS_ERR(gpio)) {
	ret = PTR_ERR(gpio);
	err_msg = "Failed to get GPIO\n";
	break;
	}

	switch (type) {
	case INT3472_GPIO_TYPE_CLK_ENABLE:
	ret = skl_int3472_register_gpio_clock(int3472, gpio);
	if (ret)
	err_msg = "Failed to register clock\n";

	break;
	case INT3472_GPIO_TYPE_PRIVACY_LED:
	ret = skl_int3472_register_pled(int3472, gpio);
	if (ret)
	err_msg = "Failed to register LED\n";

	break;
	case INT3472_GPIO_TYPE_POWER_ENABLE:
	ret = skl_int3472_register_regulator(int3472, gpio);
	if (ret)
	err_msg = "Failed to map regulator to sensor\n";

	break;
	default: /* Never reached */
	ret = -EINVAL;
	break;
	}
	break;
	default:
	dev_warn(int3472->dev,
	"GPIO type 0x%02x unknown; the sensor may not work\n",
	type);
	ret = 1;
	break;
	}

	int3472->ngpios++;
	ACPI_FREE(obj);

	if (ret < 0)
	return dev_err_probe(int3472->dev, ret, err_msg);

	return ret;
	}

	static int skl_int3472_parse_crs(struct int3472_discrete_device *int3472)
	{
	LIST_HEAD(resource_list);
	int ret;

	skl_int3472_log_sensor_module_name(int3472);

	ret = acpi_dev_get_resources(int3472->adev, &resource_list,
	skl_int3472_handle_gpio_resources,
	int3472);
	if (ret < 0)
	return ret;

	acpi_dev_free_resource_list(&resource_list);

	/* Register _DSM based clock (no-op if a GPIO clock was already registered) */
	ret = skl_int3472_register_dsm_clock(int3472);
	if (ret < 0)
	return ret;

	int3472->gpios.dev_id = int3472->sensor_name;
	gpiod_add_lookup_table(&int3472->gpios);

	return 0;
	}

	static void skl_int3472_discrete_remove(struct platform_device *pdev)
	{
	struct int3472_discrete_device *int3472 = platform_get_drvdata(pdev);

	gpiod_remove_lookup_table(&int3472->gpios);

	skl_int3472_unregister_clock(int3472);
	skl_int3472_unregister_pled(int3472);
	skl_int3472_unregister_regulator(int3472);
	}

	static int skl_int3472_discrete_probe(struct platform_device *pdev)
	{
	struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
	struct int3472_discrete_device *int3472;
	struct int3472_cldb cldb;
	int ret;

	ret = skl_int3472_fill_cldb(adev, &cldb);
	if (ret) {
	dev_err(&pdev->dev, "Couldn't fill CLDB structure\n");
	return ret;
	}

	if (cldb.control_logic_type != 1) {
	dev_err(&pdev->dev, "Unsupported control logic type %u\n",
	cldb.control_logic_type);
	return -EINVAL;
	}

	/* Max num GPIOs we've seen plus a terminator */
	int3472 = devm_kzalloc(&pdev->dev, struct_size(int3472, gpios.table,
	INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL);
	if (!int3472)
	return -ENOMEM;

	int3472->adev = adev;
	int3472->dev = &pdev->dev;
	platform_set_drvdata(pdev, int3472);
	int3472->clock.imgclk_index = cldb.clock_source;

	ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor,
	&int3472->sensor_name);
	if (ret)
	return ret;

	/*
	* Initialising this list means we can call gpiod_remove_lookup_table()
	* in failure paths without issue.
	*/
	INIT_LIST_HEAD(&int3472->gpios.list);

	ret = skl_int3472_parse_crs(int3472);
	if (ret) {
	skl_int3472_discrete_remove(pdev);
	return ret;
	}

	acpi_dev_clear_dependencies(adev);
	return 0;
	}

	static const struct acpi_device_id int3472_device_id[] = {
	{ "INT3472", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(acpi, int3472_device_id);

	static struct platform_driver int3472_discrete = {
	.driver = {
	.name = "int3472-discrete",
	.acpi_match_table = int3472_device_id,
	},
	.probe = skl_int3472_discrete_probe,
	.remove_new = skl_int3472_discrete_remove,
	};
	module_platform_driver(int3472_discrete);

	MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Discrete Device Driver");
	MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>");
	MODULE_LICENSE("GPL v2");