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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/gpio/gpio-regmap.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpio/gpio-regmap.c')
-rw-r--r-- | drivers/gpio/gpio-regmap.c | 342 |
1 files changed, 342 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c new file mode 100644 index 000000000..6383136cb --- /dev/null +++ b/drivers/gpio/gpio-regmap.c @@ -0,0 +1,342 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * regmap based generic GPIO driver + * + * Copyright 2020 Michael Walle <michael@walle.cc> + */ + +#include <linux/gpio/driver.h> +#include <linux/gpio/regmap.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/regmap.h> + +struct gpio_regmap { + struct device *parent; + struct regmap *regmap; + struct gpio_chip gpio_chip; + + int reg_stride; + int ngpio_per_reg; + unsigned int reg_dat_base; + unsigned int reg_set_base; + unsigned int reg_clr_base; + unsigned int reg_dir_in_base; + unsigned int reg_dir_out_base; + + int (*reg_mask_xlate)(struct gpio_regmap *gpio, unsigned int base, + unsigned int offset, unsigned int *reg, + unsigned int *mask); + + void *driver_data; +}; + +static unsigned int gpio_regmap_addr(unsigned int addr) +{ + if (addr == GPIO_REGMAP_ADDR_ZERO) + return 0; + + return addr; +} + +static int gpio_regmap_simple_xlate(struct gpio_regmap *gpio, + unsigned int base, unsigned int offset, + unsigned int *reg, unsigned int *mask) +{ + unsigned int line = offset % gpio->ngpio_per_reg; + unsigned int stride = offset / gpio->ngpio_per_reg; + + *reg = base + stride * gpio->reg_stride; + *mask = BIT(line); + + return 0; +} + +static int gpio_regmap_get(struct gpio_chip *chip, unsigned int offset) +{ + struct gpio_regmap *gpio = gpiochip_get_data(chip); + unsigned int base, val, reg, mask; + int ret; + + /* we might not have an output register if we are input only */ + if (gpio->reg_dat_base) + base = gpio_regmap_addr(gpio->reg_dat_base); + else + base = gpio_regmap_addr(gpio->reg_set_base); + + ret = gpio->reg_mask_xlate(gpio, base, offset, ®, &mask); + if (ret) + return ret; + + ret = regmap_read(gpio->regmap, reg, &val); + if (ret) + return ret; + + return !!(val & mask); +} + +static void gpio_regmap_set(struct gpio_chip *chip, unsigned int offset, + int val) +{ + struct gpio_regmap *gpio = gpiochip_get_data(chip); + unsigned int base = gpio_regmap_addr(gpio->reg_set_base); + unsigned int reg, mask; + + gpio->reg_mask_xlate(gpio, base, offset, ®, &mask); + if (val) + regmap_update_bits(gpio->regmap, reg, mask, mask); + else + regmap_update_bits(gpio->regmap, reg, mask, 0); +} + +static void gpio_regmap_set_with_clear(struct gpio_chip *chip, + unsigned int offset, int val) +{ + struct gpio_regmap *gpio = gpiochip_get_data(chip); + unsigned int base, reg, mask; + + if (val) + base = gpio_regmap_addr(gpio->reg_set_base); + else + base = gpio_regmap_addr(gpio->reg_clr_base); + + gpio->reg_mask_xlate(gpio, base, offset, ®, &mask); + regmap_write(gpio->regmap, reg, mask); +} + +static int gpio_regmap_get_direction(struct gpio_chip *chip, + unsigned int offset) +{ + struct gpio_regmap *gpio = gpiochip_get_data(chip); + unsigned int base, val, reg, mask; + int invert, ret; + + if (gpio->reg_dir_out_base) { + base = gpio_regmap_addr(gpio->reg_dir_out_base); + invert = 0; + } else if (gpio->reg_dir_in_base) { + base = gpio_regmap_addr(gpio->reg_dir_in_base); + invert = 1; + } else { + return -EOPNOTSUPP; + } + + ret = gpio->reg_mask_xlate(gpio, base, offset, ®, &mask); + if (ret) + return ret; + + ret = regmap_read(gpio->regmap, reg, &val); + if (ret) + return ret; + + if (!!(val & mask) ^ invert) + return GPIO_LINE_DIRECTION_OUT; + else + return GPIO_LINE_DIRECTION_IN; +} + +static int gpio_regmap_set_direction(struct gpio_chip *chip, + unsigned int offset, bool output) +{ + struct gpio_regmap *gpio = gpiochip_get_data(chip); + unsigned int base, val, reg, mask; + int invert, ret; + + if (gpio->reg_dir_out_base) { + base = gpio_regmap_addr(gpio->reg_dir_out_base); + invert = 0; + } else if (gpio->reg_dir_in_base) { + base = gpio_regmap_addr(gpio->reg_dir_in_base); + invert = 1; + } else { + return -EOPNOTSUPP; + } + + ret = gpio->reg_mask_xlate(gpio, base, offset, ®, &mask); + if (ret) + return ret; + + if (invert) + val = output ? 0 : mask; + else + val = output ? mask : 0; + + return regmap_update_bits(gpio->regmap, reg, mask, val); +} + +static int gpio_regmap_direction_input(struct gpio_chip *chip, + unsigned int offset) +{ + return gpio_regmap_set_direction(chip, offset, false); +} + +static int gpio_regmap_direction_output(struct gpio_chip *chip, + unsigned int offset, int value) +{ + gpio_regmap_set(chip, offset, value); + + return gpio_regmap_set_direction(chip, offset, true); +} + +void *gpio_regmap_get_drvdata(struct gpio_regmap *gpio) +{ + return gpio->driver_data; +} +EXPORT_SYMBOL_GPL(gpio_regmap_get_drvdata); + +/** + * gpio_regmap_register() - Register a generic regmap GPIO controller + * @config: configuration for gpio_regmap + * + * Return: A pointer to the registered gpio_regmap or ERR_PTR error value. + */ +struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config) +{ + struct gpio_regmap *gpio; + struct gpio_chip *chip; + int ret; + + if (!config->parent) + return ERR_PTR(-EINVAL); + + if (!config->ngpio) + return ERR_PTR(-EINVAL); + + /* we need at least one */ + if (!config->reg_dat_base && !config->reg_set_base) + return ERR_PTR(-EINVAL); + + /* if we have a direction register we need both input and output */ + if ((config->reg_dir_out_base || config->reg_dir_in_base) && + (!config->reg_dat_base || !config->reg_set_base)) + return ERR_PTR(-EINVAL); + + /* we don't support having both registers simultaneously for now */ + if (config->reg_dir_out_base && config->reg_dir_in_base) + return ERR_PTR(-EINVAL); + + gpio = kzalloc(sizeof(*gpio), GFP_KERNEL); + if (!gpio) + return ERR_PTR(-ENOMEM); + + gpio->parent = config->parent; + gpio->driver_data = config->drvdata; + gpio->regmap = config->regmap; + gpio->ngpio_per_reg = config->ngpio_per_reg; + gpio->reg_stride = config->reg_stride; + gpio->reg_mask_xlate = config->reg_mask_xlate; + gpio->reg_dat_base = config->reg_dat_base; + gpio->reg_set_base = config->reg_set_base; + gpio->reg_clr_base = config->reg_clr_base; + gpio->reg_dir_in_base = config->reg_dir_in_base; + gpio->reg_dir_out_base = config->reg_dir_out_base; + + /* if not set, assume there is only one register */ + if (!gpio->ngpio_per_reg) + gpio->ngpio_per_reg = config->ngpio; + + /* if not set, assume they are consecutive */ + if (!gpio->reg_stride) + gpio->reg_stride = 1; + + if (!gpio->reg_mask_xlate) + gpio->reg_mask_xlate = gpio_regmap_simple_xlate; + + chip = &gpio->gpio_chip; + chip->parent = config->parent; + chip->fwnode = config->fwnode; + chip->base = -1; + chip->ngpio = config->ngpio; + chip->names = config->names; + chip->label = config->label ?: dev_name(config->parent); + + /* + * If our regmap is fast_io we should probably set can_sleep to false. + * Right now, the regmap doesn't save this property, nor is there any + * access function for it. + * The only regmap type which uses fast_io is regmap-mmio. For now, + * assume a safe default of true here. + */ + chip->can_sleep = true; + + chip->get = gpio_regmap_get; + if (gpio->reg_set_base && gpio->reg_clr_base) + chip->set = gpio_regmap_set_with_clear; + else if (gpio->reg_set_base) + chip->set = gpio_regmap_set; + + if (gpio->reg_dir_in_base || gpio->reg_dir_out_base) { + chip->get_direction = gpio_regmap_get_direction; + chip->direction_input = gpio_regmap_direction_input; + chip->direction_output = gpio_regmap_direction_output; + } + + ret = gpiochip_add_data(chip, gpio); + if (ret < 0) + goto err_free_gpio; + + if (config->irq_domain) { + ret = gpiochip_irqchip_add_domain(chip, config->irq_domain); + if (ret) + goto err_remove_gpiochip; + } + + return gpio; + +err_remove_gpiochip: + gpiochip_remove(chip); +err_free_gpio: + kfree(gpio); + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(gpio_regmap_register); + +/** + * gpio_regmap_unregister() - Unregister a generic regmap GPIO controller + * @gpio: gpio_regmap device to unregister + */ +void gpio_regmap_unregister(struct gpio_regmap *gpio) +{ + gpiochip_remove(&gpio->gpio_chip); + kfree(gpio); +} +EXPORT_SYMBOL_GPL(gpio_regmap_unregister); + +static void devm_gpio_regmap_unregister(void *res) +{ + gpio_regmap_unregister(res); +} + +/** + * devm_gpio_regmap_register() - resource managed gpio_regmap_register() + * @dev: device that is registering this GPIO device + * @config: configuration for gpio_regmap + * + * Managed gpio_regmap_register(). For generic regmap GPIO device registered by + * this function, gpio_regmap_unregister() is automatically called on driver + * detach. See gpio_regmap_register() for more information. + * + * Return: A pointer to the registered gpio_regmap or ERR_PTR error value. + */ +struct gpio_regmap *devm_gpio_regmap_register(struct device *dev, + const struct gpio_regmap_config *config) +{ + struct gpio_regmap *gpio; + int ret; + + gpio = gpio_regmap_register(config); + + if (IS_ERR(gpio)) + return gpio; + + ret = devm_add_action_or_reset(dev, devm_gpio_regmap_unregister, gpio); + if (ret) + return ERR_PTR(ret); + + return gpio; +} +EXPORT_SYMBOL_GPL(devm_gpio_regmap_register); + +MODULE_AUTHOR("Michael Walle <michael@walle.cc>"); +MODULE_DESCRIPTION("GPIO generic regmap driver core"); +MODULE_LICENSE("GPL"); |