drivers/gpio/gpio-regmap.c - linux - Git at Google

 // 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, &reg, &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, &reg, &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, &reg, &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, &reg, &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, &reg, &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->base = -1;
 	chip->ngpio = config->ngpio;
 	chip->names = config->names;
 	chip->label = config->label ?: dev_name(config->parent);

 #if defined(CONFIG_OF_GPIO)
 	/* gpiolib will use of_node of the parent if chip->of_node is NULL */
 	chip->of_node = to_of_node(config->fwnode);
 #endif /* CONFIG_OF_GPIO */

 	/*
 	 * 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");
	// 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, &reg, &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, &reg, &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, &reg, &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, &reg, &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, &reg, &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->base = -1;
	chip->ngpio = config->ngpio;
	chip->names = config->names;
	chip->label = config->label ?: dev_name(config->parent);

	#if defined(CONFIG_OF_GPIO)
	/* gpiolib will use of_node of the parent if chip->of_node is NULL */
	chip->of_node = to_of_node(config->fwnode);
	#endif /* CONFIG_OF_GPIO */

	/*
	* 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");