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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/regulator/gpio-regulator.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/regulator/gpio-regulator.c')
-rw-r--r-- | drivers/regulator/gpio-regulator.c | 390 |
1 files changed, 390 insertions, 0 deletions
diff --git a/drivers/regulator/gpio-regulator.c b/drivers/regulator/gpio-regulator.c new file mode 100644 index 000000000..95e61a2f4 --- /dev/null +++ b/drivers/regulator/gpio-regulator.c @@ -0,0 +1,390 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * gpio-regulator.c + * + * Copyright 2011 Heiko Stuebner <heiko@sntech.de> + * + * based on fixed.c + * + * Copyright 2008 Wolfson Microelectronics PLC. + * + * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> + * + * Copyright (c) 2009 Nokia Corporation + * Roger Quadros <ext-roger.quadros@nokia.com> + * + * This is useful for systems with mixed controllable and + * non-controllable regulators, as well as for allowing testing on + * systems with no controllable regulators. + */ + +#include <linux/err.h> +#include <linux/mutex.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regulator/driver.h> +#include <linux/regulator/machine.h> +#include <linux/regulator/of_regulator.h> +#include <linux/regulator/gpio-regulator.h> +#include <linux/gpio/consumer.h> +#include <linux/slab.h> +#include <linux/of.h> + +struct gpio_regulator_data { + struct regulator_desc desc; + + struct gpio_desc **gpiods; + int nr_gpios; + + struct gpio_regulator_state *states; + int nr_states; + + int state; +}; + +static int gpio_regulator_get_value(struct regulator_dev *dev) +{ + struct gpio_regulator_data *data = rdev_get_drvdata(dev); + int ptr; + + for (ptr = 0; ptr < data->nr_states; ptr++) + if (data->states[ptr].gpios == data->state) + return data->states[ptr].value; + + return -EINVAL; +} + +static int gpio_regulator_set_voltage(struct regulator_dev *dev, + int min_uV, int max_uV, + unsigned *selector) +{ + struct gpio_regulator_data *data = rdev_get_drvdata(dev); + int ptr, target = 0, state, best_val = INT_MAX; + + for (ptr = 0; ptr < data->nr_states; ptr++) + if (data->states[ptr].value < best_val && + data->states[ptr].value >= min_uV && + data->states[ptr].value <= max_uV) { + target = data->states[ptr].gpios; + best_val = data->states[ptr].value; + if (selector) + *selector = ptr; + } + + if (best_val == INT_MAX) + return -EINVAL; + + for (ptr = 0; ptr < data->nr_gpios; ptr++) { + state = (target & (1 << ptr)) >> ptr; + gpiod_set_value_cansleep(data->gpiods[ptr], state); + } + data->state = target; + + return 0; +} + +static int gpio_regulator_list_voltage(struct regulator_dev *dev, + unsigned selector) +{ + struct gpio_regulator_data *data = rdev_get_drvdata(dev); + + if (selector >= data->nr_states) + return -EINVAL; + + return data->states[selector].value; +} + +static int gpio_regulator_set_current_limit(struct regulator_dev *dev, + int min_uA, int max_uA) +{ + struct gpio_regulator_data *data = rdev_get_drvdata(dev); + int ptr, target = 0, state, best_val = 0; + + for (ptr = 0; ptr < data->nr_states; ptr++) + if (data->states[ptr].value > best_val && + data->states[ptr].value >= min_uA && + data->states[ptr].value <= max_uA) { + target = data->states[ptr].gpios; + best_val = data->states[ptr].value; + } + + if (best_val == 0) + return -EINVAL; + + for (ptr = 0; ptr < data->nr_gpios; ptr++) { + state = (target & (1 << ptr)) >> ptr; + gpiod_set_value_cansleep(data->gpiods[ptr], state); + } + data->state = target; + + return 0; +} + +static const struct regulator_ops gpio_regulator_voltage_ops = { + .get_voltage = gpio_regulator_get_value, + .set_voltage = gpio_regulator_set_voltage, + .list_voltage = gpio_regulator_list_voltage, +}; + +static struct gpio_regulator_config * +of_get_gpio_regulator_config(struct device *dev, struct device_node *np, + const struct regulator_desc *desc) +{ + struct gpio_regulator_config *config; + const char *regtype; + int proplen, i; + int ngpios; + int ret; + + config = devm_kzalloc(dev, + sizeof(struct gpio_regulator_config), + GFP_KERNEL); + if (!config) + return ERR_PTR(-ENOMEM); + + config->init_data = of_get_regulator_init_data(dev, np, desc); + if (!config->init_data) + return ERR_PTR(-EINVAL); + + config->supply_name = config->init_data->constraints.name; + + if (config->init_data->constraints.boot_on) + config->enabled_at_boot = true; + + /* + * Do not use: undocumented device tree property. + * This is kept around solely for device tree ABI stability. + */ + if (of_property_read_bool(np, "enable-at-boot")) + config->enabled_at_boot = true; + + of_property_read_u32(np, "startup-delay-us", &config->startup_delay); + + /* Fetch GPIO init levels */ + ngpios = gpiod_count(dev, NULL); + if (ngpios > 0) { + config->gflags = devm_kzalloc(dev, + sizeof(enum gpiod_flags) + * ngpios, + GFP_KERNEL); + if (!config->gflags) + return ERR_PTR(-ENOMEM); + + for (i = 0; i < ngpios; i++) { + u32 val; + + ret = of_property_read_u32_index(np, "gpios-states", i, + &val); + + /* Default to high per specification */ + if (ret) + config->gflags[i] = GPIOD_OUT_HIGH; + else + config->gflags[i] = + val ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW; + } + } + config->ngpios = ngpios; + + /* Fetch states. */ + proplen = of_property_count_u32_elems(np, "states"); + if (proplen < 0) { + dev_err(dev, "No 'states' property found\n"); + return ERR_PTR(-EINVAL); + } + + config->states = devm_kcalloc(dev, + proplen / 2, + sizeof(struct gpio_regulator_state), + GFP_KERNEL); + if (!config->states) + return ERR_PTR(-ENOMEM); + + for (i = 0; i < proplen / 2; i++) { + of_property_read_u32_index(np, "states", i * 2, + &config->states[i].value); + of_property_read_u32_index(np, "states", i * 2 + 1, + &config->states[i].gpios); + } + config->nr_states = i; + + config->type = REGULATOR_VOLTAGE; + ret = of_property_read_string(np, "regulator-type", ®type); + if (ret >= 0) { + if (!strncmp("voltage", regtype, 7)) + config->type = REGULATOR_VOLTAGE; + else if (!strncmp("current", regtype, 7)) + config->type = REGULATOR_CURRENT; + else + dev_warn(dev, "Unknown regulator-type '%s'\n", + regtype); + } + + if (of_find_property(np, "vin-supply", NULL)) + config->input_supply = "vin"; + + return config; +} + +static const struct regulator_ops gpio_regulator_current_ops = { + .get_current_limit = gpio_regulator_get_value, + .set_current_limit = gpio_regulator_set_current_limit, +}; + +static int gpio_regulator_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct gpio_regulator_config *config = dev_get_platdata(dev); + struct device_node *np = dev->of_node; + struct gpio_regulator_data *drvdata; + struct regulator_config cfg = { }; + struct regulator_dev *rdev; + enum gpiod_flags gflags; + int ptr, ret, state, i; + + drvdata = devm_kzalloc(dev, sizeof(struct gpio_regulator_data), + GFP_KERNEL); + if (drvdata == NULL) + return -ENOMEM; + + if (np) { + config = of_get_gpio_regulator_config(dev, np, + &drvdata->desc); + if (IS_ERR(config)) + return PTR_ERR(config); + } + + drvdata->desc.name = devm_kstrdup(dev, config->supply_name, GFP_KERNEL); + if (drvdata->desc.name == NULL) { + dev_err(dev, "Failed to allocate supply name\n"); + return -ENOMEM; + } + + drvdata->gpiods = devm_kzalloc(dev, sizeof(struct gpio_desc *), + GFP_KERNEL); + + if (config->input_supply) { + drvdata->desc.supply_name = devm_kstrdup(&pdev->dev, + config->input_supply, + GFP_KERNEL); + if (!drvdata->desc.supply_name) { + dev_err(&pdev->dev, + "Failed to allocate input supply\n"); + return -ENOMEM; + } + } + + if (!drvdata->gpiods) + return -ENOMEM; + for (i = 0; i < config->ngpios; i++) { + drvdata->gpiods[i] = devm_gpiod_get_index(dev, + NULL, + i, + config->gflags[i]); + if (IS_ERR(drvdata->gpiods[i])) + return PTR_ERR(drvdata->gpiods[i]); + /* This is good to know */ + gpiod_set_consumer_name(drvdata->gpiods[i], drvdata->desc.name); + } + drvdata->nr_gpios = config->ngpios; + + drvdata->states = devm_kmemdup(dev, + config->states, + config->nr_states * + sizeof(struct gpio_regulator_state), + GFP_KERNEL); + if (drvdata->states == NULL) { + dev_err(dev, "Failed to allocate state data\n"); + return -ENOMEM; + } + drvdata->nr_states = config->nr_states; + + drvdata->desc.owner = THIS_MODULE; + drvdata->desc.enable_time = config->startup_delay; + + /* handle regulator type*/ + switch (config->type) { + case REGULATOR_VOLTAGE: + drvdata->desc.type = REGULATOR_VOLTAGE; + drvdata->desc.ops = &gpio_regulator_voltage_ops; + drvdata->desc.n_voltages = config->nr_states; + break; + case REGULATOR_CURRENT: + drvdata->desc.type = REGULATOR_CURRENT; + drvdata->desc.ops = &gpio_regulator_current_ops; + break; + default: + dev_err(dev, "No regulator type set\n"); + return -EINVAL; + } + + /* build initial state from gpio init data. */ + state = 0; + for (ptr = 0; ptr < drvdata->nr_gpios; ptr++) { + if (config->gflags[ptr] == GPIOD_OUT_HIGH) + state |= (1 << ptr); + } + drvdata->state = state; + + cfg.dev = dev; + cfg.init_data = config->init_data; + cfg.driver_data = drvdata; + cfg.of_node = np; + + /* + * The signal will be inverted by the GPIO core if flagged so in the + * descriptor. + */ + if (config->enabled_at_boot) + gflags = GPIOD_OUT_HIGH | GPIOD_FLAGS_BIT_NONEXCLUSIVE; + else + gflags = GPIOD_OUT_LOW | GPIOD_FLAGS_BIT_NONEXCLUSIVE; + + cfg.ena_gpiod = gpiod_get_optional(dev, "enable", gflags); + if (IS_ERR(cfg.ena_gpiod)) + return PTR_ERR(cfg.ena_gpiod); + + rdev = devm_regulator_register(dev, &drvdata->desc, &cfg); + if (IS_ERR(rdev)) { + ret = PTR_ERR(rdev); + dev_err(dev, "Failed to register regulator: %d\n", ret); + return ret; + } + + platform_set_drvdata(pdev, drvdata); + + return 0; +} + +#if defined(CONFIG_OF) +static const struct of_device_id regulator_gpio_of_match[] = { + { .compatible = "regulator-gpio", }, + {}, +}; +MODULE_DEVICE_TABLE(of, regulator_gpio_of_match); +#endif + +static struct platform_driver gpio_regulator_driver = { + .probe = gpio_regulator_probe, + .driver = { + .name = "gpio-regulator", + .of_match_table = of_match_ptr(regulator_gpio_of_match), + }, +}; + +static int __init gpio_regulator_init(void) +{ + return platform_driver_register(&gpio_regulator_driver); +} +subsys_initcall(gpio_regulator_init); + +static void __exit gpio_regulator_exit(void) +{ + platform_driver_unregister(&gpio_regulator_driver); +} +module_exit(gpio_regulator_exit); + +MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>"); +MODULE_DESCRIPTION("gpio voltage regulator"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:gpio-regulator"); |