root/include/linux/gpio/driver.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_GPIO_DRIVER_H
#define __LINUX_GPIO_DRIVER_H

#include <linux/bits.h>
#include <linux/cleanup.h>
#include <linux/err.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/irqhandler.h>
#include <linux/lockdep.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/property.h>
#include <linux/spinlock_types.h>
#include <linux/types.h>
#include <linux/util_macros.h>

#ifdef CONFIG_GENERIC_MSI_IRQ
#include <asm/msi.h>
#endif

struct device;
struct irq_chip;
struct irq_data;
struct module;
struct of_phandle_args;
struct pinctrl_dev;
struct seq_file;

struct gpio_chip;
struct gpio_desc;
struct gpio_device;

enum gpio_lookup_flags;
enum gpiod_flags;

union gpio_irq_fwspec {
        struct irq_fwspec       fwspec;
#ifdef CONFIG_GENERIC_MSI_IRQ
        msi_alloc_info_t        msiinfo;
#endif
};

#define GPIO_LINE_DIRECTION_IN  1
#define GPIO_LINE_DIRECTION_OUT 0

/**
 * struct gpio_irq_chip - GPIO interrupt controller
 */
struct gpio_irq_chip {
        /**
         * @chip:
         *
         * GPIO IRQ chip implementation, provided by GPIO driver.
         */
        struct irq_chip *chip;

        /**
         * @domain:
         *
         * Interrupt translation domain; responsible for mapping between GPIO
         * hwirq number and Linux IRQ number.
         */
        struct irq_domain *domain;

#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
        /**
         * @fwnode:
         *
         * Firmware node corresponding to this gpiochip/irqchip, necessary
         * for hierarchical irqdomain support.
         */
        struct fwnode_handle *fwnode;

        /**
         * @parent_domain:
         *
         * If non-NULL, will be set as the parent of this GPIO interrupt
         * controller's IRQ domain to establish a hierarchical interrupt
         * domain. The presence of this will activate the hierarchical
         * interrupt support.
         */
        struct irq_domain *parent_domain;

        /**
         * @child_to_parent_hwirq:
         *
         * This callback translates a child hardware IRQ offset to a parent
         * hardware IRQ offset on a hierarchical interrupt chip. The child
         * hardware IRQs correspond to the GPIO index 0..ngpio-1 (see the
         * ngpio field of struct gpio_chip) and the corresponding parent
         * hardware IRQ and type (such as IRQ_TYPE_*) shall be returned by
         * the driver. The driver can calculate this from an offset or using
         * a lookup table or whatever method is best for this chip. Return
         * 0 on successful translation in the driver.
         *
         * If some ranges of hardware IRQs do not have a corresponding parent
         * HWIRQ, return -EINVAL, but also make sure to fill in @valid_mask and
         * @need_valid_mask to make these GPIO lines unavailable for
         * translation.
         */
        int (*child_to_parent_hwirq)(struct gpio_chip *gc,
                                     unsigned int child_hwirq,
                                     unsigned int child_type,
                                     unsigned int *parent_hwirq,
                                     unsigned int *parent_type);

        /**
         * @populate_parent_alloc_arg :
         *
         * This optional callback allocates and populates the specific struct
         * for the parent's IRQ domain. If this is not specified, then
         * &gpiochip_populate_parent_fwspec_twocell will be used. A four-cell
         * variant named &gpiochip_populate_parent_fwspec_fourcell is also
         * available.
         */
        int (*populate_parent_alloc_arg)(struct gpio_chip *gc,
                                         union gpio_irq_fwspec *fwspec,
                                         unsigned int parent_hwirq,
                                         unsigned int parent_type);

        /**
         * @child_offset_to_irq:
         *
         * This optional callback is used to translate the child's GPIO line
         * offset on the GPIO chip to an IRQ number for the GPIO to_irq()
         * callback. If this is not specified, then a default callback will be
         * provided that returns the line offset.
         */
        unsigned int (*child_offset_to_irq)(struct gpio_chip *gc,
                                            unsigned int pin);

        /**
         * @child_irq_domain_ops:
         *
         * The IRQ domain operations that will be used for this GPIO IRQ
         * chip. If no operations are provided, then default callbacks will
         * be populated to setup the IRQ hierarchy. Some drivers need to
         * supply their own translate function.
         */
        struct irq_domain_ops child_irq_domain_ops;
#endif

        /**
         * @handler:
         *
         * The IRQ handler to use (often a predefined IRQ core function) for
         * GPIO IRQs, provided by GPIO driver.
         */
        irq_flow_handler_t handler;

        /**
         * @default_type:
         *
         * Default IRQ triggering type applied during GPIO driver
         * initialization, provided by GPIO driver.
         */
        unsigned int default_type;

        /**
         * @lock_key:
         *
         * Per GPIO IRQ chip lockdep class for IRQ lock.
         */
        struct lock_class_key *lock_key;

        /**
         * @request_key:
         *
         * Per GPIO IRQ chip lockdep class for IRQ request.
         */
        struct lock_class_key *request_key;

        /**
         * @parent_handler:
         *
         * The interrupt handler for the GPIO chip's parent interrupts, may be
         * NULL if the parent interrupts are nested rather than cascaded.
         */
        irq_flow_handler_t parent_handler;

        union {
                /**
                 * @parent_handler_data:
                 *
                 * If @per_parent_data is false, @parent_handler_data is a
                 * single pointer used as the data associated with every
                 * parent interrupt.
                 */
                void *parent_handler_data;

                /**
                 * @parent_handler_data_array:
                 *
                 * If @per_parent_data is true, @parent_handler_data_array is
                 * an array of @num_parents pointers, and is used to associate
                 * different data for each parent. This cannot be NULL if
                 * @per_parent_data is true.
                 */
                void **parent_handler_data_array;
        };

        /**
         * @num_parents:
         *
         * The number of interrupt parents of a GPIO chip.
         */
        unsigned int num_parents;

        /**
         * @parents:
         *
         * A list of interrupt parents of a GPIO chip. This is owned by the
         * driver, so the core will only reference this list, not modify it.
         */
        unsigned int *parents;

        /**
         * @map:
         *
         * A list of interrupt parents for each line of a GPIO chip.
         */
        unsigned int *map;

        /**
         * @threaded:
         *
         * True if set the interrupt handling uses nested threads.
         */
        bool threaded;

        /**
         * @per_parent_data:
         *
         * True if parent_handler_data_array describes a @num_parents
         * sized array to be used as parent data.
         */
        bool per_parent_data;

        /**
         * @initialized:
         *
         * Flag to track GPIO chip irq member's initialization.
         * This flag will make sure GPIO chip irq members are not used
         * before they are initialized.
         */
        bool initialized;

        /**
         * @domain_is_allocated_externally:
         *
         * True it the irq_domain was allocated outside of gpiolib, in which
         * case gpiolib won't free the irq_domain itself.
         */
        bool domain_is_allocated_externally;

        /**
         * @init_hw: optional routine to initialize hardware before
         * an IRQ chip will be added. This is quite useful when
         * a particular driver wants to clear IRQ related registers
         * in order to avoid undesired events.
         */
        int (*init_hw)(struct gpio_chip *gc);

        /**
         * @init_valid_mask: optional routine to initialize @valid_mask, to be
         * used if not all GPIO lines are valid interrupts. Sometimes some
         * lines just cannot fire interrupts, and this routine, when defined,
         * is passed a bitmap in "valid_mask" and it will have ngpios
         * bits from 0..(ngpios-1) set to "1" as in valid. The callback can
         * then directly set some bits to "0" if they cannot be used for
         * interrupts.
         */
        void (*init_valid_mask)(struct gpio_chip *gc,
                                unsigned long *valid_mask,
                                unsigned int ngpios);

        /**
         * @valid_mask:
         *
         * If not %NULL, holds bitmask of GPIOs which are valid to be included
         * in IRQ domain of the chip.
         */
        unsigned long *valid_mask;

        /**
         * @first:
         *
         * Required for static IRQ allocation. If set,
         * irq_domain_create_simple() will allocate and map all IRQs
         * during initialization.
         */
        unsigned int first;

        /**
         * @irq_enable:
         *
         * Store old irq_chip irq_enable callback
         */
        void            (*irq_enable)(struct irq_data *data);

        /**
         * @irq_disable:
         *
         * Store old irq_chip irq_disable callback
         */
        void            (*irq_disable)(struct irq_data *data);
        /**
         * @irq_unmask:
         *
         * Store old irq_chip irq_unmask callback
         */
        void            (*irq_unmask)(struct irq_data *data);

        /**
         * @irq_mask:
         *
         * Store old irq_chip irq_mask callback
         */
        void            (*irq_mask)(struct irq_data *data);
};

/**
 * struct gpio_chip - abstract a GPIO controller
 * @label: a functional name for the GPIO device, such as a part
 *      number or the name of the SoC IP-block implementing it.
 * @gpiodev: the internal state holder, opaque struct
 * @parent: optional parent device providing the GPIOs
 * @fwnode: optional fwnode providing this controller's properties
 * @owner: helps prevent removal of modules exporting active GPIOs
 * @request: optional hook for chip-specific activation, such as
 *      enabling module power and clock; may sleep; must return 0 on success
 *      or negative error number on failure
 * @free: optional hook for chip-specific deactivation, such as
 *      disabling module power and clock; may sleep
 * @get_direction: returns direction for signal "offset", 0=out, 1=in,
 *      (same as GPIO_LINE_DIRECTION_OUT / GPIO_LINE_DIRECTION_IN),
 *      or negative error. It is recommended to always implement this
 *      function, even on input-only or output-only gpio chips.
 * @direction_input: configures signal "offset" as input, returns 0 on success
 *      or a negative error number. This can be omitted on input-only or
 *      output-only gpio chips.
 * @direction_output: configures signal "offset" as output, returns 0 on
 *      success or a negative error number. This can be omitted on input-only
 *      or output-only gpio chips.
 * @get: returns value for signal "offset", 0=low, 1=high, or negative error
 * @get_multiple: reads values for multiple signals defined by "mask" and
 *      stores them in "bits", returns 0 on success or negative error
 * @set: assigns output value for signal "offset", returns 0 on success or
 *       negative error value
 * @set_multiple: assigns output values for multiple signals defined by
 *                "mask", returns 0 on success or negative error value
 * @set_config: optional hook for all kinds of settings. Uses the same
 *      packed config format as generic pinconf. Must return 0 on success and
 *      a negative error number on failure.
 * @to_irq: optional hook supporting non-static gpiod_to_irq() mappings;
 *      implementation may not sleep
 * @dbg_show: optional routine to show contents in debugfs; default code
 *      will be used when this is omitted, but custom code can show extra
 *      state (such as pullup/pulldown configuration).
 * @init_valid_mask: optional routine to initialize @valid_mask, to be used if
 *      not all GPIOs are valid.
 * @add_pin_ranges: optional routine to initialize pin ranges, to be used when
 *      requires special mapping of the pins that provides GPIO functionality.
 *      It is called after adding GPIO chip and before adding IRQ chip.
 * @en_hw_timestamp: Dependent on GPIO chip, an optional routine to
 *      enable hardware timestamp.
 * @dis_hw_timestamp: Dependent on GPIO chip, an optional routine to
 *      disable hardware timestamp.
 * @base: identifies the first GPIO number handled by this chip;
 *      or, if negative during registration, requests dynamic ID allocation.
 *      DEPRECATION: providing anything non-negative and nailing the base
 *      offset of GPIO chips is deprecated. Please pass -1 as base to
 *      let gpiolib select the chip base in all possible cases. We want to
 *      get rid of the static GPIO number space in the long run.
 * @ngpio: the number of GPIOs handled by this controller; the last GPIO
 *      handled is (base + ngpio - 1).
 * @offset: when multiple gpio chips belong to the same device this
 *      can be used as offset within the device so friendly names can
 *      be properly assigned.
 * @names: if set, must be an array of strings to use as alternative
 *      names for the GPIOs in this chip. Any entry in the array
 *      may be NULL if there is no alias for the GPIO, however the
 *      array must be @ngpio entries long.
 * @can_sleep: flag must be set iff get()/set() methods sleep, as they
 *      must while accessing GPIO expander chips over I2C or SPI. This
 *      implies that if the chip supports IRQs, these IRQs need to be threaded
 *      as the chip access may sleep when e.g. reading out the IRQ status
 *      registers.
 *
 * A gpio_chip can help platforms abstract various sources of GPIOs so
 * they can all be accessed through a common programming interface.
 * Example sources would be SOC controllers, FPGAs, multifunction
 * chips, dedicated GPIO expanders, and so on.
 *
 * Each chip controls a number of signals, identified in method calls
 * by "offset" values in the range 0..(@ngpio - 1).  When those signals
 * are referenced through calls like gpio_get_value(gpio), the offset
 * is calculated by subtracting @base from the gpio number.
 */
struct gpio_chip {
        const char              *label;
        struct gpio_device      *gpiodev;
        struct device           *parent;
        struct fwnode_handle    *fwnode;
        struct module           *owner;

        int                     (*request)(struct gpio_chip *gc,
                                                unsigned int offset);
        void                    (*free)(struct gpio_chip *gc,
                                                unsigned int offset);
        int                     (*get_direction)(struct gpio_chip *gc,
                                                unsigned int offset);
        int                     (*direction_input)(struct gpio_chip *gc,
                                                unsigned int offset);
        int                     (*direction_output)(struct gpio_chip *gc,
                                                unsigned int offset, int value);
        int                     (*get)(struct gpio_chip *gc,
                                                unsigned int offset);
        int                     (*get_multiple)(struct gpio_chip *gc,
                                                unsigned long *mask,
                                                unsigned long *bits);
        int                     (*set)(struct gpio_chip *gc,
                                       unsigned int offset, int value);
        int                     (*set_multiple)(struct gpio_chip *gc,
                                                unsigned long *mask,
                                                unsigned long *bits);
        int                     (*set_config)(struct gpio_chip *gc,
                                              unsigned int offset,
                                              unsigned long config);
        int                     (*to_irq)(struct gpio_chip *gc,
                                                unsigned int offset);

        void                    (*dbg_show)(struct seq_file *s,
                                                struct gpio_chip *gc);

        int                     (*init_valid_mask)(struct gpio_chip *gc,
                                                   unsigned long *valid_mask,
                                                   unsigned int ngpios);

        int                     (*add_pin_ranges)(struct gpio_chip *gc);

        int                     (*en_hw_timestamp)(struct gpio_chip *gc,
                                                   u32 offset,
                                                   unsigned long flags);
        int                     (*dis_hw_timestamp)(struct gpio_chip *gc,
                                                    u32 offset,
                                                    unsigned long flags);
        int                     base;
        u16                     ngpio;
        u16                     offset;
        const char              *const *names;
        bool                    can_sleep;

#ifdef CONFIG_GPIOLIB_IRQCHIP
        /*
         * With CONFIG_GPIOLIB_IRQCHIP we get an irqchip inside the gpiolib
         * to handle IRQs for most practical cases.
         */

        /**
         * @irq:
         *
         * Integrates interrupt chip functionality with the GPIO chip. Can be
         * used to handle IRQs for most practical cases.
         */
        struct gpio_irq_chip irq;
#endif /* CONFIG_GPIOLIB_IRQCHIP */

#if defined(CONFIG_OF_GPIO)
        /*
         * If CONFIG_OF_GPIO is enabled, then all GPIO controllers described in
         * the device tree automatically may have an OF translation
         */

        /**
         * @of_gpio_n_cells:
         *
         * Number of cells used to form the GPIO specifier. The standard is 2
         * cells:
         *
         * gpios = <&gpio offset flags>;
         *
         * some complex GPIO controllers instantiate more than one chip per
         * device tree node and have 3 cells:
         *
         * gpios = <&gpio instance offset flags>;
         *
         * Legacy GPIO controllers may even have 1 cell:
         *
         * gpios = <&gpio offset>;
         */
        unsigned int of_gpio_n_cells;

        /**
         * @of_node_instance_match:
         *
         * Determine if a chip is the right instance. Must be implemented by
         * any driver using more than one gpio_chip per device tree node.
         * Returns true if gc is the instance indicated by i (which is the
         * first cell in the phandles for GPIO lines and gpio-ranges).
         */
        bool (*of_node_instance_match)(struct gpio_chip *gc, unsigned int i);

        /**
         * @of_xlate:
         *
         * Callback to translate a device tree GPIO specifier into a chip-
         * relative GPIO number and flags.
         */
        int (*of_xlate)(struct gpio_chip *gc,
                        const struct of_phandle_args *gpiospec, u32 *flags);
#endif /* CONFIG_OF_GPIO */
};

char *gpiochip_dup_line_label(struct gpio_chip *gc, unsigned int offset);


struct _gpiochip_for_each_data {
        const char **label;
        unsigned int *i;
};

DEFINE_CLASS(_gpiochip_for_each_data,
             struct _gpiochip_for_each_data,
             if (*_T.label) kfree(*_T.label),
             ({
                struct _gpiochip_for_each_data _data = { label, i };
                *_data.i = 0;
                _data;
             }),
             const char **label, int *i)

/**
 * for_each_hwgpio_in_range - Iterates over all GPIOs in a given range
 * @_chip: Chip to iterate over.
 * @_i: Loop counter.
 * @_base: First GPIO in the ranger.
 * @_size: Amount of GPIOs to check starting from @base.
 * @_label: Place to store the address of the label if the GPIO is requested.
 *          Set to NULL for unused GPIOs.
 */
#define for_each_hwgpio_in_range(_chip, _i, _base, _size, _label)                       \
        for (CLASS(_gpiochip_for_each_data, _data)(&_label, &_i);                       \
             _i < _size;                                                                \
             _i++, kfree(_label), _label = NULL)                                        \
                for_each_if(!IS_ERR(_label = gpiochip_dup_line_label(_chip, _base + _i)))

/**
 * for_each_hwgpio - Iterates over all GPIOs for given chip.
 * @_chip: Chip to iterate over.
 * @_i: Loop counter.
 * @_label: Place to store the address of the label if the GPIO is requested.
 *          Set to NULL for unused GPIOs.
 */
#define for_each_hwgpio(_chip, _i, _label)                                              \
        for_each_hwgpio_in_range(_chip, _i, 0, _chip->ngpio, _label)

/**
 * for_each_requested_gpio_in_range - iterates over requested GPIOs in a given range
 * @_chip:      the chip to query
 * @_i:         loop variable
 * @_base:      first GPIO in the range
 * @_size:      amount of GPIOs to check starting from @base
 * @_label:     label of current GPIO
 */
#define for_each_requested_gpio_in_range(_chip, _i, _base, _size, _label)               \
        for_each_hwgpio_in_range(_chip, _i, _base, _size, _label)                       \
                for_each_if(_label)

/* Iterates over all requested GPIO of the given @chip */
#define for_each_requested_gpio(chip, i, label)                                         \
        for_each_requested_gpio_in_range(chip, i, 0, chip->ngpio, label)

/* add/remove chips */
int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
                               struct lock_class_key *lock_key,
                               struct lock_class_key *request_key);

/**
 * gpiochip_add_data() - register a gpio_chip
 * @gc: the chip to register, with gc->base initialized
 * @data: driver-private data associated with this chip
 *
 * Context: potentially before irqs will work
 *
 * When gpiochip_add_data() is called very early during boot, so that GPIOs
 * can be freely used, the gc->parent device must be registered before
 * the gpio framework's arch_initcall().  Otherwise sysfs initialization
 * for GPIOs will fail rudely.
 *
 * gpiochip_add_data() must only be called after gpiolib initialization,
 * i.e. after core_initcall().
 *
 * If gc->base is negative, this requests dynamic assignment of
 * a range of valid GPIOs.
 *
 * Returns:
 * A negative errno if the chip can't be registered, such as because the
 * gc->base is invalid or already associated with a different chip.
 * Otherwise it returns zero as a success code.
 */
#ifdef CONFIG_LOCKDEP
#define gpiochip_add_data(gc, data) ({          \
                static struct lock_class_key lock_key;  \
                static struct lock_class_key request_key;         \
                gpiochip_add_data_with_key(gc, data, &lock_key, \
                                           &request_key);         \
        })
#define devm_gpiochip_add_data(dev, gc, data) ({ \
                static struct lock_class_key lock_key;  \
                static struct lock_class_key request_key;         \
                devm_gpiochip_add_data_with_key(dev, gc, data, &lock_key, \
                                           &request_key);         \
        })
#else
#define gpiochip_add_data(gc, data) gpiochip_add_data_with_key(gc, data, NULL, NULL)
#define devm_gpiochip_add_data(dev, gc, data) \
        devm_gpiochip_add_data_with_key(dev, gc, data, NULL, NULL)
#endif /* CONFIG_LOCKDEP */

void gpiochip_remove(struct gpio_chip *gc);
int devm_gpiochip_add_data_with_key(struct device *dev, struct gpio_chip *gc,
                                    void *data, struct lock_class_key *lock_key,
                                    struct lock_class_key *request_key);

struct gpio_device *gpio_device_find(const void *data,
                                int (*match)(struct gpio_chip *gc,
                                             const void *data));

struct gpio_device *gpio_device_get(struct gpio_device *gdev);
void gpio_device_put(struct gpio_device *gdev);

DEFINE_FREE(gpio_device_put, struct gpio_device *,
            if (!IS_ERR_OR_NULL(_T)) gpio_device_put(_T))

struct device *gpio_device_to_device(struct gpio_device *gdev);

bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset);
int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset);
void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset);
void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset);
void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset);

/* irq_data versions of the above */
int gpiochip_irq_reqres(struct irq_data *data);
void gpiochip_irq_relres(struct irq_data *data);

/* Paste this in your irq_chip structure  */
#define GPIOCHIP_IRQ_RESOURCE_HELPERS                                   \
                .irq_request_resources  = gpiochip_irq_reqres,          \
                .irq_release_resources  = gpiochip_irq_relres

static inline void gpio_irq_chip_set_chip(struct gpio_irq_chip *girq,
                                          const struct irq_chip *chip)
{
        /* Yes, dropping const is ugly, but it isn't like we have a choice */
        girq->chip = (struct irq_chip *)chip;
}

/* Line status inquiry for drivers */
bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset);
bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset);

/* Sleep persistence inquiry for drivers */
bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset);
bool gpiochip_line_is_valid(const struct gpio_chip *gc, unsigned int offset);
const unsigned long *gpiochip_query_valid_mask(const struct gpio_chip *gc);

/* get driver data */
void *gpiochip_get_data(struct gpio_chip *gc);

#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY

int gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc,
                                            union gpio_irq_fwspec *gfwspec,
                                            unsigned int parent_hwirq,
                                            unsigned int parent_type);
int gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
                                             union gpio_irq_fwspec *gfwspec,
                                             unsigned int parent_hwirq,
                                             unsigned int parent_type);

#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */

#ifdef CONFIG_GPIOLIB_IRQCHIP
int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
                                struct irq_domain *domain);
#else

#include <asm/bug.h>

static inline int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
                                              struct irq_domain *domain)
{
        WARN_ON(1);
        return -EINVAL;
}
#endif

int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset);
void gpiochip_generic_free(struct gpio_chip *gc, unsigned int offset);
int gpiochip_generic_config(struct gpio_chip *gc, unsigned int offset,
                            unsigned long config);

/**
 * struct gpio_pin_range - pin range controlled by a gpio chip
 * @node: list for maintaining set of pin ranges, used internally
 * @pctldev: pinctrl device which handles corresponding pins
 * @range: actual range of pins controlled by a gpio controller
 */
struct gpio_pin_range {
        struct list_head node;
        struct pinctrl_dev *pctldev;
        struct pinctrl_gpio_range range;
};

#ifdef CONFIG_PINCTRL

int gpiochip_add_pin_range_with_pins(struct gpio_chip *gc,
                                     const char *pinctl_name,
                                     unsigned int gpio_offset,
                                     unsigned int pin_offset,
                                     unsigned int const *pins,
                                     unsigned int npins);
int gpiochip_add_pingroup_range(struct gpio_chip *gc,
                        struct pinctrl_dev *pctldev,
                        unsigned int gpio_offset, const char *pin_group);
void gpiochip_remove_pin_ranges(struct gpio_chip *gc);

static inline int
gpiochip_add_pin_range(struct gpio_chip *gc,
                       const char *pinctl_name,
                       unsigned int gpio_offset,
                       unsigned int pin_offset,
                       unsigned int npins)
{
        return gpiochip_add_pin_range_with_pins(gc, pinctl_name, gpio_offset,
                                                pin_offset, NULL, npins);
}

static inline int
gpiochip_add_sparse_pin_range(struct gpio_chip *gc,
                              const char *pinctl_name,
                              unsigned int gpio_offset,
                              unsigned int const *pins,
                              unsigned int npins)
{
        return gpiochip_add_pin_range_with_pins(gc, pinctl_name, gpio_offset, 0,
                                                pins, npins);
}
#else /* ! CONFIG_PINCTRL */

static inline int
gpiochip_add_pin_range_with_pins(struct gpio_chip *gc,
                                 const char *pinctl_name,
                                 unsigned int gpio_offset,
                                 unsigned int pin_offset,
                                 unsigned int npins)
{
        return 0;
}

static inline int
gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name,
                       unsigned int gpio_offset, unsigned int pin_offset,
                       unsigned int npins)
{
        return 0;
}

static inline int
gpiochip_add_sparse_pin_range(struct gpio_chip *gc,
                              const char *pinctl_name,
                              unsigned int gpio_offset,
                              unsigned int const *pins,
                              unsigned int npins)
{
        return 0;
}

static inline int
gpiochip_add_pingroup_range(struct gpio_chip *gc,
                        struct pinctrl_dev *pctldev,
                        unsigned int gpio_offset, const char *pin_group)
{
        return 0;
}

static inline void
gpiochip_remove_pin_ranges(struct gpio_chip *gc)
{
}

#endif /* CONFIG_PINCTRL */

struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
                                            unsigned int hwnum,
                                            const char *label,
                                            enum gpio_lookup_flags lflags,
                                            enum gpiod_flags dflags);
void gpiochip_free_own_desc(struct gpio_desc *desc);

struct gpio_desc *
gpio_device_get_desc(struct gpio_device *gdev, unsigned int hwnum);

struct gpio_chip *gpio_device_get_chip(struct gpio_device *gdev);

#ifdef CONFIG_GPIOLIB

/* lock/unlock as IRQ */
int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset);
void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset);

struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc);
struct gpio_device *gpiod_to_gpio_device(struct gpio_desc *desc);

/* struct gpio_device getters */
int gpio_device_get_base(struct gpio_device *gdev);
const char *gpio_device_get_label(struct gpio_device *gdev);

struct gpio_device *gpio_device_find_by_label(const char *label);
struct gpio_device *gpio_device_find_by_fwnode(const struct fwnode_handle *fwnode);

#else /* CONFIG_GPIOLIB */

#include <asm/bug.h>

static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
{
        /* GPIO can never have been requested */
        WARN_ON(1);
        return ERR_PTR(-ENODEV);
}

static inline struct gpio_device *gpiod_to_gpio_device(struct gpio_desc *desc)
{
        WARN_ON(1);
        return ERR_PTR(-ENODEV);
}

static inline int gpio_device_get_base(struct gpio_device *gdev)
{
        WARN_ON(1);
        return -ENODEV;
}

static inline const char *gpio_device_get_label(struct gpio_device *gdev)
{
        WARN_ON(1);
        return NULL;
}

static inline struct gpio_device *gpio_device_find_by_label(const char *label)
{
        WARN_ON(1);
        return NULL;
}

static inline struct gpio_device *gpio_device_find_by_fwnode(const struct fwnode_handle *fwnode)
{
        WARN_ON(1);
        return NULL;
}

static inline int gpiochip_lock_as_irq(struct gpio_chip *gc,
                                       unsigned int offset)
{
        WARN_ON(1);
        return -EINVAL;
}

static inline void gpiochip_unlock_as_irq(struct gpio_chip *gc,
                                          unsigned int offset)
{
        WARN_ON(1);
}
#endif /* CONFIG_GPIOLIB */

#define for_each_gpiochip_node(dev, child)                                      \
        device_for_each_child_node(dev, child)                                  \
                for_each_if(fwnode_property_present(child, "gpio-controller"))

static inline unsigned int gpiochip_node_count(struct device *dev)
{
        struct fwnode_handle *child;
        unsigned int count = 0;

        for_each_gpiochip_node(dev, child)
                count++;

        return count;
}

static inline struct fwnode_handle *gpiochip_node_get_first(struct device *dev)
{
        struct fwnode_handle *fwnode;

        for_each_gpiochip_node(dev, fwnode)
                return fwnode;

        return NULL;
}

#endif /* __LINUX_GPIO_DRIVER_H */