diff options
Diffstat (limited to 'drivers/platform/x86/intel/int3472/clk_and_regulator.c')
-rw-r--r-- | drivers/platform/x86/intel/int3472/clk_and_regulator.c | 352 |
1 files changed, 352 insertions, 0 deletions
diff --git a/drivers/platform/x86/intel/int3472/clk_and_regulator.c b/drivers/platform/x86/intel/int3472/clk_and_regulator.c new file mode 100644 index 0000000000..ef4b3141ef --- /dev/null +++ b/drivers/platform/x86/intel/int3472/clk_and_regulator.c @@ -0,0 +1,352 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Author: Dan Scally <djrscally@gmail.com> */ + +#include <linux/acpi.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/device.h> +#include <linux/dmi.h> +#include <linux/gpio/consumer.h> +#include <linux/regulator/driver.h> +#include <linux/slab.h> + +#include "common.h" + +/* + * 82c0d13a-78c5-4244-9bb1-eb8b539a8d11 + * This _DSM GUID allows controlling the sensor clk when it is not controlled + * through a GPIO. + */ +static const guid_t img_clk_guid = + GUID_INIT(0x82c0d13a, 0x78c5, 0x4244, + 0x9b, 0xb1, 0xeb, 0x8b, 0x53, 0x9a, 0x8d, 0x11); + +static void skl_int3472_enable_clk(struct int3472_clock *clk, int enable) +{ + struct int3472_discrete_device *int3472 = to_int3472_device(clk); + union acpi_object args[3]; + union acpi_object argv4; + + if (clk->ena_gpio) { + gpiod_set_value_cansleep(clk->ena_gpio, enable); + return; + } + + args[0].integer.type = ACPI_TYPE_INTEGER; + args[0].integer.value = clk->imgclk_index; + args[1].integer.type = ACPI_TYPE_INTEGER; + args[1].integer.value = enable; + args[2].integer.type = ACPI_TYPE_INTEGER; + args[2].integer.value = 1; + + argv4.type = ACPI_TYPE_PACKAGE; + argv4.package.count = 3; + argv4.package.elements = args; + + acpi_evaluate_dsm(acpi_device_handle(int3472->adev), &img_clk_guid, + 0, 1, &argv4); +} + +/* + * The regulators have to have .ops to be valid, but the only ops we actually + * support are .enable and .disable which are handled via .ena_gpiod. Pass an + * empty struct to clear the check without lying about capabilities. + */ +static const struct regulator_ops int3472_gpio_regulator_ops; + +static int skl_int3472_clk_prepare(struct clk_hw *hw) +{ + skl_int3472_enable_clk(to_int3472_clk(hw), 1); + return 0; +} + +static void skl_int3472_clk_unprepare(struct clk_hw *hw) +{ + skl_int3472_enable_clk(to_int3472_clk(hw), 0); +} + +static int skl_int3472_clk_enable(struct clk_hw *hw) +{ + /* + * We're just turning a GPIO on to enable the clock, which operation + * has the potential to sleep. Given .enable() cannot sleep, but + * .prepare() can, we toggle the GPIO in .prepare() instead. Thus, + * nothing to do here. + */ + return 0; +} + +static void skl_int3472_clk_disable(struct clk_hw *hw) +{ + /* Likewise, nothing to do here... */ +} + +static unsigned int skl_int3472_get_clk_frequency(struct int3472_discrete_device *int3472) +{ + union acpi_object *obj; + unsigned int freq; + + obj = skl_int3472_get_acpi_buffer(int3472->sensor, "SSDB"); + if (IS_ERR(obj)) + return 0; /* report rate as 0 on error */ + + if (obj->buffer.length < CIO2_SENSOR_SSDB_MCLKSPEED_OFFSET + sizeof(u32)) { + dev_err(int3472->dev, "The buffer is too small\n"); + kfree(obj); + return 0; + } + + freq = *(u32 *)(obj->buffer.pointer + CIO2_SENSOR_SSDB_MCLKSPEED_OFFSET); + + kfree(obj); + return freq; +} + +static unsigned long skl_int3472_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct int3472_clock *clk = to_int3472_clk(hw); + + return clk->frequency; +} + +static const struct clk_ops skl_int3472_clock_ops = { + .prepare = skl_int3472_clk_prepare, + .unprepare = skl_int3472_clk_unprepare, + .enable = skl_int3472_clk_enable, + .disable = skl_int3472_clk_disable, + .recalc_rate = skl_int3472_clk_recalc_rate, +}; + +int skl_int3472_register_dsm_clock(struct int3472_discrete_device *int3472) +{ + struct acpi_device *adev = int3472->adev; + struct clk_init_data init = { + .ops = &skl_int3472_clock_ops, + .flags = CLK_GET_RATE_NOCACHE, + }; + int ret; + + if (int3472->clock.cl) + return 0; /* A GPIO controlled clk has already been registered */ + + if (!acpi_check_dsm(adev->handle, &img_clk_guid, 0, BIT(1))) + return 0; /* DSM clock control is not available */ + + init.name = kasprintf(GFP_KERNEL, "%s-clk", acpi_dev_name(adev)); + if (!init.name) + return -ENOMEM; + + int3472->clock.frequency = skl_int3472_get_clk_frequency(int3472); + int3472->clock.clk_hw.init = &init; + int3472->clock.clk = clk_register(&adev->dev, &int3472->clock.clk_hw); + if (IS_ERR(int3472->clock.clk)) { + ret = PTR_ERR(int3472->clock.clk); + goto out_free_init_name; + } + + int3472->clock.cl = clkdev_create(int3472->clock.clk, NULL, int3472->sensor_name); + if (!int3472->clock.cl) { + ret = -ENOMEM; + goto err_unregister_clk; + } + + kfree(init.name); + return 0; + +err_unregister_clk: + clk_unregister(int3472->clock.clk); +out_free_init_name: + kfree(init.name); + return ret; +} + +int skl_int3472_register_gpio_clock(struct int3472_discrete_device *int3472, + struct acpi_resource_gpio *agpio, u32 polarity) +{ + char *path = agpio->resource_source.string_ptr; + struct clk_init_data init = { + .ops = &skl_int3472_clock_ops, + .flags = CLK_GET_RATE_NOCACHE, + }; + int ret; + + if (int3472->clock.cl) + return -EBUSY; + + int3472->clock.ena_gpio = acpi_get_and_request_gpiod(path, agpio->pin_table[0], + "int3472,clk-enable"); + if (IS_ERR(int3472->clock.ena_gpio)) { + ret = PTR_ERR(int3472->clock.ena_gpio); + int3472->clock.ena_gpio = NULL; + return dev_err_probe(int3472->dev, ret, "getting clk-enable GPIO\n"); + } + + if (polarity == GPIO_ACTIVE_LOW) + gpiod_toggle_active_low(int3472->clock.ena_gpio); + + /* Ensure the pin is in output mode and non-active state */ + gpiod_direction_output(int3472->clock.ena_gpio, 0); + + init.name = kasprintf(GFP_KERNEL, "%s-clk", + acpi_dev_name(int3472->adev)); + if (!init.name) { + ret = -ENOMEM; + goto out_put_gpio; + } + + int3472->clock.frequency = skl_int3472_get_clk_frequency(int3472); + + int3472->clock.clk_hw.init = &init; + int3472->clock.clk = clk_register(&int3472->adev->dev, + &int3472->clock.clk_hw); + if (IS_ERR(int3472->clock.clk)) { + ret = PTR_ERR(int3472->clock.clk); + goto out_free_init_name; + } + + int3472->clock.cl = clkdev_create(int3472->clock.clk, NULL, + int3472->sensor_name); + if (!int3472->clock.cl) { + ret = -ENOMEM; + goto err_unregister_clk; + } + + kfree(init.name); + return 0; + +err_unregister_clk: + clk_unregister(int3472->clock.clk); +out_free_init_name: + kfree(init.name); +out_put_gpio: + gpiod_put(int3472->clock.ena_gpio); + + return ret; +} + +void skl_int3472_unregister_clock(struct int3472_discrete_device *int3472) +{ + if (!int3472->clock.cl) + return; + + clkdev_drop(int3472->clock.cl); + clk_unregister(int3472->clock.clk); + gpiod_put(int3472->clock.ena_gpio); +} + +/* + * The INT3472 device is going to be the only supplier of a regulator for + * the sensor device. But unlike the clk framework the regulator framework + * does not allow matching by consumer-device-name only. + * + * Ideally all sensor drivers would use "avdd" as supply-id. But for drivers + * where this cannot be changed because another supply-id is already used in + * e.g. DeviceTree files an alias for the other supply-id can be added here. + * + * Do not forget to update GPIO_REGULATOR_SUPPLY_MAP_COUNT when changing this. + */ +static const char * const skl_int3472_regulator_map_supplies[] = { + "avdd", + "AVDD", +}; + +static_assert(ARRAY_SIZE(skl_int3472_regulator_map_supplies) == + GPIO_REGULATOR_SUPPLY_MAP_COUNT); + +/* + * On some models there is a single GPIO regulator which is shared between + * sensors and only listed in the ACPI resources of one sensor. + * This DMI table contains the name of the second sensor. This is used to add + * entries for the second sensor to the supply_map. + */ +static const struct dmi_system_id skl_int3472_regulator_second_sensor[] = { + { + /* Lenovo Miix 510-12IKB */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_VERSION, "MIIX 510-12IKB"), + }, + .driver_data = "i2c-OVTI2680:00", + }, + { } +}; + +int skl_int3472_register_regulator(struct int3472_discrete_device *int3472, + struct acpi_resource_gpio *agpio) +{ + char *path = agpio->resource_source.string_ptr; + struct regulator_init_data init_data = { }; + struct regulator_config cfg = { }; + const char *second_sensor = NULL; + const struct dmi_system_id *id; + int i, j, ret; + + id = dmi_first_match(skl_int3472_regulator_second_sensor); + if (id) + second_sensor = id->driver_data; + + for (i = 0, j = 0; i < ARRAY_SIZE(skl_int3472_regulator_map_supplies); i++) { + int3472->regulator.supply_map[j].supply = skl_int3472_regulator_map_supplies[i]; + int3472->regulator.supply_map[j].dev_name = int3472->sensor_name; + j++; + + if (second_sensor) { + int3472->regulator.supply_map[j].supply = + skl_int3472_regulator_map_supplies[i]; + int3472->regulator.supply_map[j].dev_name = second_sensor; + j++; + } + } + + init_data.constraints.valid_ops_mask = REGULATOR_CHANGE_STATUS; + init_data.consumer_supplies = int3472->regulator.supply_map; + init_data.num_consumer_supplies = j; + + snprintf(int3472->regulator.regulator_name, + sizeof(int3472->regulator.regulator_name), "%s-regulator", + acpi_dev_name(int3472->adev)); + snprintf(int3472->regulator.supply_name, + GPIO_REGULATOR_SUPPLY_NAME_LENGTH, "supply-0"); + + int3472->regulator.rdesc = INT3472_REGULATOR( + int3472->regulator.regulator_name, + int3472->regulator.supply_name, + &int3472_gpio_regulator_ops); + + int3472->regulator.gpio = acpi_get_and_request_gpiod(path, agpio->pin_table[0], + "int3472,regulator"); + if (IS_ERR(int3472->regulator.gpio)) { + ret = PTR_ERR(int3472->regulator.gpio); + int3472->regulator.gpio = NULL; + return dev_err_probe(int3472->dev, ret, "getting regulator GPIO\n"); + } + + /* Ensure the pin is in output mode and non-active state */ + gpiod_direction_output(int3472->regulator.gpio, 0); + + cfg.dev = &int3472->adev->dev; + cfg.init_data = &init_data; + cfg.ena_gpiod = int3472->regulator.gpio; + + int3472->regulator.rdev = regulator_register(int3472->dev, + &int3472->regulator.rdesc, + &cfg); + if (IS_ERR(int3472->regulator.rdev)) { + ret = PTR_ERR(int3472->regulator.rdev); + goto err_free_gpio; + } + + return 0; + +err_free_gpio: + gpiod_put(int3472->regulator.gpio); + + return ret; +} + +void skl_int3472_unregister_regulator(struct int3472_discrete_device *int3472) +{ + regulator_unregister(int3472->regulator.rdev); + gpiod_put(int3472->regulator.gpio); +} |