diff options
Diffstat (limited to 'drivers/platform/x86/intel/int3472/discrete.c')
| -rw-r--r-- | drivers/platform/x86/intel/int3472/discrete.c | 349 |
1 files changed, 349 insertions, 0 deletions
diff --git a/drivers/platform/x86/intel/int3472/discrete.c b/drivers/platform/x86/intel/int3472/discrete.c new file mode 100644 index 0000000000..e33c2d7597 --- /dev/null +++ b/drivers/platform/x86/intel/int3472/discrete.c @@ -0,0 +1,349 @@ +// 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_map_gpio_to_sensor(struct int3472_discrete_device *int3472, + struct acpi_resource_gpio *agpio, + const char *func, u32 polarity) +{ + char *path = agpio->resource_source.string_ptr; + struct gpiod_lookup *table_entry; + struct acpi_device *adev; + acpi_handle handle; + acpi_status status; + + if (int3472->n_sensor_gpios >= INT3472_MAX_SENSOR_GPIOS) { + dev_warn(int3472->dev, "Too many GPIOs mapped\n"); + return -EINVAL; + } + + 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 = &int3472->gpios.table[int3472->n_sensor_gpios]; + 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; + + int3472->n_sensor_gpios++; + + return 0; +} + +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; + 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: + ret = skl_int3472_register_gpio_clock(int3472, agpio, polarity); + if (ret) + err_msg = "Failed to register clock\n"; + + break; + case INT3472_GPIO_TYPE_PRIVACY_LED: + ret = skl_int3472_register_pled(int3472, agpio, polarity); + if (ret) + err_msg = "Failed to register LED\n"; + + break; + case INT3472_GPIO_TYPE_POWER_ENABLE: + ret = skl_int3472_register_regulator(int3472, agpio); + if (ret) + err_msg = "Failed to map regulator to sensor\n"; + + 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"); |