/* SPDX-License-Identifier: GPL-2.0+ */
/*
 * Copyright (C) 2015  Masahiro Yamada <yamada.masahiro@com>
 */

#ifndef __PINCTRL_H
#define __PINCTRL_H

#define PINNAME_SIZE    10
#define PINMUX_SIZE     40

/**
 * struct pinconf_param - pin config parameters
 * @property:           Property name in DT nodes
 * @param:              ID for this config parameter
 * @default_value:      default value for this config parameter used in case
 *                      no value is specified in DT nodes
 */
struct pinconf_param {
        const char * const property;
        unsigned int param;
        u32 default_value;
};

/**
 * struct pinctrl_ops - pin control operations, to be implemented by
 * pin controller drivers.
 *
 * set_state() is the only mandatory operation. You can implement your pinctrl
 * driver with its own @set_state. In this case, the other callbacks are not
 * required. Otherwise, generic pinctrl framework is also available; use
 * pinctrl_generic_set_state for @set_state, and implement other operations
 * depending on your necessity.
 */
struct pinctrl_ops {
        /**
         * @get_pins_count: Get the number of selectable pins
         *
         * @dev: Pinctrl device to use
         *
         * This function is necessary to parse the "pins" property in DTS.
         *
         * @Return:
         *      number of selectable named pins available in this driver
         */
        int (*get_pins_count)(struct udevice *dev);

        /**
         * @get_pin_name: Get the name of a pin
         *
         * @dev: Pinctrl device of the pin
         *
         * @selector: The pin selector
         *
         * This function is called by the core to figure out which pin it will
         * do operations to. This function is necessary to parse the "pins"
         * property in DTS.
         *
         * @Return: const pointer to the name of the pin
         */
        const char *(*get_pin_name)(struct udevice *dev, unsigned selector);

        /**
         * @get_groups_count: Get the number of selectable groups
         *
         * @dev: Pinctrl device to use
         *
         * This function is necessary to parse the "groups" property in DTS.
         *
         * @Return:
         *      number of selectable named groups available in the driver
         */
        int (*get_groups_count)(struct udevice *dev);

        /**
         * @get_group_name: Get the name of a group
         *
         * @dev: Pinctrl device of the group
         *
         * @selector: The group selector
         *
         * This function is called by the core to figure out which group it
         * will do operations to. This function is necessary to parse the
         * "groups" property in DTS.
         *
         * @Return: Pointer to the name of the group
         */
        const char *(*get_group_name)(struct udevice *dev, unsigned selector);

        /**
         * @get_functions_count: Get the number of selectable functions
         *
         * @dev: Pinctrl device to use
         *
         * This function is necessary for pin-muxing.
         *
         * @Return:
         *      number of selectable named functions available in this driver
         */
        int (*get_functions_count)(struct udevice *dev);

        /**
         * @get_function_name: Get the name of a function
         *
         * @dev: Pinmux device of the function
         *
         * @selector: The function selector
         *
         * This function is called by the core to figure out which mux setting
         * it will map a certain device to. This function is necessary for
         * pin-muxing.
         *
         * @Return:
         *      Pointer to the function name of the muxing selector
         */
        const char *(*get_function_name)(struct udevice *dev,
                                         unsigned selector);

        /**
         * @pinmux_set: Mux a pin to a function
         *
         * @dev: Pinctrl device to use
         *
         * @pin_selector: The pin selector
         *
         * @func_selector: The func selector
         *
         * On simple controllers one of @pin_selector or @func_selector may be
         * ignored. This function is necessary for pin-muxing against a single
         * pin.
         *
         * @Return: 0 if OK, or negative error code on failure
         */
        int (*pinmux_set)(struct udevice *dev, unsigned pin_selector,
                          unsigned func_selector);

        /**
         * @pinmux_group_set: Mux a group of pins to a function
         *
         * @dev: Pinctrl device to use
         *
         * @group_selector: The group selector
         *
         * @func_selector: The func selector
         *
         * On simple controllers one of @group_selector or @func_selector may be
         * ignored. This function is necessary for pin-muxing against a group of
         * pins.
         *
         * @Return: 0 if OK, or negative error code on failure
         */
        int (*pinmux_group_set)(struct udevice *dev, unsigned group_selector,
                                unsigned func_selector);

        /**
         * @pinmux_property_set: Enable a pinmux group
         *
         * @dev: Pinctrl device to use
         *
         * @pinmux_group: A u32 representing the pin identifier and mux
         *                settings. The exact format of a pinmux group is left
         *                up to the driver.
         *
         * Mux a single pin to a single function based on a driver-specific
         * pinmux group. This function is necessary for parsing the "pinmux"
         * property in DTS, and for pin-muxing against a pinmux group.
         *
         * @Return:
         *      Pin selector for the muxed pin if OK, or negative error code on
         *      failure
         */
        int (*pinmux_property_set)(struct udevice *dev, u32 pinmux_group);

        /**
         * @pinconf_num_params:
         *      Number of driver-specific parameters to be parsed from device
         *      trees. This member is necessary for pin configuration.
         */
        unsigned int pinconf_num_params;

        /**
         * @pinconf_params:
         *      List of driver-specific parameters to be parsed from the device
         *      tree. This member is necessary for pin configuration.
         */
        const struct pinconf_param *pinconf_params;

        /**
         * @pinconf_set: Configure an individual pin with a parameter
         *
         * @dev: Pinctrl device to use
         *
         * @pin_selector: The pin selector
         *
         * @param: An &enum pin_config_param from @pinconf_params
         *
         * @argument: The argument to this param from the device tree, or
         *            @pinconf_params.default_value
         *
         * This function is necessary for pin configuration against a single
         * pin.
         *
         * @Return: 0 if OK, or negative error code on failure
         */
        int (*pinconf_set)(struct udevice *dev, unsigned pin_selector,
                           unsigned param, unsigned argument);

        /**
         * @pinconf_group_set: Configure all pins in a group with a parameter
         *
         * @dev: Pinctrl device to use
         *
         * @pin_selector: The group selector
         *
         * @param: A &enum pin_config_param from
         *         @pinconf_params
         *
         * @argument: The argument to this param from the device tree, or
         *            @pinconf_params.default_value
         *
         * This function is necessary for pin configuration against a group of
         * pins.
         *
         * @Return: 0 if OK, or negative error code on failure
         */
        int (*pinconf_group_set)(struct udevice *dev, unsigned group_selector,
                                 unsigned param, unsigned argument);

        /**
         * @set_state: Configure a pinctrl device
         *
         * @dev: Pinctrl device to use
         *
         * @config: Pseudo device pointing a config node
         *
         * This function is required to be implemented by all pinctrl drivers.
         * Drivers may set this member to pinctrl_generic_set_state(), which
         * will call other functions in &struct pinctrl_ops to parse
         * @config.
         *
         * @Return: 0 if OK, or negative error code on failure
         */
        int (*set_state)(struct udevice *dev, struct udevice *config);

        /**
         * @set_state_simple: Configure a pinctrl device
         *
         * @dev: Pinctrl device to use
         *
         * @config: Pseudo-device pointing a config node
         *
         * This function is usually a simpler version of set_state(). Only the
         * first pinctrl device on the system is supported by this function.
         *
         * @Return: 0 if OK, or negative error code on failure
         */
        int (*set_state_simple)(struct udevice *dev, struct udevice *periph);

        /**
         * @request: Request a particular pinctrl function
         *
         * @dev: Device to adjust (%UCLASS_PINCTRL)
         *
         * @func: Function number (driver-specific)
         *
         * This activates the selected function.
         *
         * @Return: 0 if OK, or negative error code on failure
         */
        int (*request)(struct udevice *dev, int func, int flags);

        /**
        * @get_periph_id: Get the peripheral ID for a device
        *
        * @dev: Pinctrl device to use for decoding
        *
        * @periph: Device to check
        *
        * This generally looks at the peripheral's device tree node to work
        * out the peripheral ID. The return value is normally interpreted as
        * &enum periph_id. so long as this is defined by the platform (which it
        * should be).
        *
        * @Return:
        *       Peripheral ID of @periph, or %-ENOENT on error
        */
        int (*get_periph_id)(struct udevice *dev, struct udevice *periph);

        /**
         * @get_gpio_mux: Get the mux value for a particular GPIO
         *
         * @dev: Pinctrl device to use
         *
         * @banknum: GPIO bank number
         *
         * @index: GPIO index within the bank
         *
         * This allows the raw mux value for a GPIO to be obtained. It is
         * useful for displaying the function being used by that GPIO, such
         * as with the 'gpio' command. This function is internal to the GPIO
         * subsystem and should not be used by generic code. Typically it is
         * used by a GPIO driver with knowledge of the SoC pinctrl setup.
         *
         * @Return:
         *      Mux value (SoC-specific, e.g. 0 for input, 1 for output)
         */
        int (*get_gpio_mux)(struct udevice *dev, int banknum, int index);

        /**
         * @get_pin_muxing: Show pin muxing
         *
         * @dev: Pinctrl device to use
         *
         * @selector: Pin selector
         *
         * @buf: Buffer to fill with pin muxing description
         *
         * @size: Size of @buf
         *
         * This allows to display the muxing of a given pin. It's useful for
         * debug purposes to know if a pin is configured as GPIO or as an
         * alternate function and which one. Typically it is used by a PINCTRL
         * driver with knowledge of the SoC pinctrl setup.
         *
         * @Return: 0 if OK, or negative error code on failure
         */
         int (*get_pin_muxing)(struct udevice *dev, unsigned int selector,
                               char *buf, int size);

        /**
         * @gpio_request_enable: Request and enable GPIO on a certain pin.
         *
         * @dev: Pinctrl device to use
         *
         * @selector: Pin selector
         *
         * Implement this only if you can mux every pin individually as GPIO.
         * The affected GPIO range is passed along with an offset(pin number)
         * into that specific GPIO range - function selectors and pin groups are
         * orthogonal to this, the core will however make sure the pins do not
         * collide.
         *
         * @Return:
         *      0 if OK, or negative error code on failure
         */
        int (*gpio_request_enable)(struct udevice *dev, unsigned int selector);

        /**
         * @gpio_disable_free: Free up GPIO muxing on a certain pin.
         *
         * @dev: Pinctrl device to use
         *
         * @selector: Pin selector
         *
         * This function is the reverse of @gpio_request_enable.
         *
         * @Return: 0 if OK, or negative error code on failure
         */
        int (*gpio_disable_free)(struct udevice *dev, unsigned int selector);
};

#define pinctrl_get_ops(dev)    ((struct pinctrl_ops *)(dev)->driver->ops)

/**
 * enum pin_config_param - Generic pin configuration parameters
 *
 * @PIN_CONFIG_BIAS_BUS_HOLD: The pin will be set to weakly latch so that it
 *      weakly drives the last value on a tristate bus, also known as a "bus
 *      holder", "bus keeper" or "repeater". This allows another device on the
 *      bus to change the value by driving the bus high or low and switching to
 *      tristate. The argument is ignored.
 * @PIN_CONFIG_BIAS_DISABLE: Disable any pin bias on the pin, a
 *      transition from say pull-up to pull-down implies that you disable
 *      pull-up in the process, this setting disables all biasing.
 * @PIN_CONFIG_BIAS_HIGH_IMPEDANCE: The pin will be set to a high impedance
 *      mode, also know as "third-state" (tristate) or "high-Z" or "floating".
 *      On output pins this effectively disconnects the pin, which is useful
 *      if for example some other pin is going to drive the signal connected
 *      to it for a while. Pins used for input are usually always high
 *      impedance.
 * @PIN_CONFIG_BIAS_PULL_DOWN: The pin will be pulled down (usually with high
 *      impedance to GROUND). If the argument is != 0 pull-down is enabled,
 *      if it is 0, pull-down is total, i.e. the pin is connected to GROUND.
 * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: The pin will be pulled up or down based
 *      on embedded knowledge of the controller hardware, like current mux
 *      function. The pull direction and possibly strength too will normally
 *      be decided completely inside the hardware block and not be readable
 *      from the kernel side.
 *      If the argument is != 0 pull up/down is enabled, if it is 0, the
 *      configuration is ignored. The proper way to disable it is to use
 *      @PIN_CONFIG_BIAS_DISABLE.
 * @PIN_CONFIG_BIAS_PULL_UP: The pin will be pulled up (usually with high
 *      impedance to VDD). If the argument is != 0 pull-up is enabled,
 *      if it is 0, pull-up is total, i.e. the pin is connected to VDD.
 * @PIN_CONFIG_DRIVE_OPEN_DRAIN: The pin will be driven with open drain (open
 *      collector) which means it is usually wired with other output ports
 *      which are then pulled up with an external resistor. Setting this
 *      config will enable open drain mode, the argument is ignored.
 * @PIN_CONFIG_DRIVE_OPEN_SOURCE: The pin will be driven with open source
 *      (open emitter). Setting this config will enable open source mode, the
 *      argument is ignored.
 * @PIN_CONFIG_DRIVE_PUSH_PULL: The pin will be driven actively high and
 *      low, this is the most typical case and is typically achieved with two
 *      active transistors on the output. Setting this config will enable
 *      push-pull mode, the argument is ignored.
 * @PIN_CONFIG_DRIVE_STRENGTH: The pin will sink or source at most the current
 *      passed as argument. The argument is in mA.
 * @PIN_CONFIG_DRIVE_STRENGTH_UA: The pin will sink or source at most the
 *      current passed as argument. The argument is in uA.
 * @PIN_CONFIG_INPUT_DEBOUNCE: This will configure the pin to debounce mode,
 *      which means it will wait for signals to settle when reading inputs. The
 *      argument gives the debounce time in usecs. Setting the
 *      argument to zero turns debouncing off.
 * @PIN_CONFIG_INPUT_ENABLE: Enable the pin's input.  Note that this does not
 *      affect the pin's ability to drive output.  1 enables input, 0 disables
 *      input.
 * @PIN_CONFIG_INPUT_SCHMITT: This will configure an input pin to run in
 *      schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis,
 *      the threshold value is given on a custom format as argument when
 *      setting pins to this mode.
 * @PIN_CONFIG_INPUT_SCHMITT_ENABLE: Control schmitt-trigger mode on the pin.
 *      If the argument != 0, schmitt-trigger mode is enabled. If it's 0,
 *      schmitt-trigger mode is disabled.
 * @PIN_CONFIG_LOW_POWER_MODE: This will configure the pin for low power
 *      operation, if several modes of operation are supported these can be
 *      passed in the argument on a custom form, else just use argument 1
 *      to indicate low power mode, argument 0 turns low power mode off.
 * @PIN_CONFIG_OUTPUT_ENABLE: This will enable the pin's output mode
 *      without driving a value there. For most platforms this reduces to
 *      enable the output buffers and then let the pin controller current
 *      configuration (eg. the currently selected mux function) drive values on
 *      the line. Use argument 1 to enable output mode, argument 0 to disable
 *      it.
 * @PIN_CONFIG_OUTPUT: This will configure the pin as an output and drive a
 *      value on the line. Use argument 1 to indicate high level, argument 0 to
 *      indicate low level. (Please see Documentation/driver-api/pinctl.rst,
 *      section "GPIO mode pitfalls" for a discussion around this parameter.)
 * @PIN_CONFIG_POWER_SOURCE: If the pin can select between different power
 *      supplies, the argument to this parameter (on a custom format) tells
 *      the driver which alternative power source to use.
 * @PIN_CONFIG_SLEEP_HARDWARE_STATE: Indicate this is sleep related state.
 * @PIN_CONFIG_SLEW_RATE: If the pin can select slew rate, the argument to
 *      this parameter (on a custom format) tells the driver which alternative
 *      slew rate to use.
 * @PIN_CONFIG_SKEW_DELAY: If the pin has programmable skew rate (on inputs)
 *      or latch delay (on outputs) this parameter (in a custom format)
 *      specifies the clock skew or latch delay. It typically controls how
 *      many double inverters are put in front of the line.
 * @PIN_CONFIG_END: This is the last enumerator for pin configurations, if
 *      you need to pass in custom configurations to the pin controller, use
 *      PIN_CONFIG_END+1 as the base offset.
 * @PIN_CONFIG_MAX: This is the maximum configuration value that can be
 *      presented using the packed format.
 */
enum pin_config_param {
        PIN_CONFIG_BIAS_BUS_HOLD,
        PIN_CONFIG_BIAS_DISABLE,
        PIN_CONFIG_BIAS_HIGH_IMPEDANCE,
        PIN_CONFIG_BIAS_PULL_DOWN,
        PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
        PIN_CONFIG_BIAS_PULL_UP,
        PIN_CONFIG_DRIVE_OPEN_DRAIN,
        PIN_CONFIG_DRIVE_OPEN_SOURCE,
        PIN_CONFIG_DRIVE_PUSH_PULL,
        PIN_CONFIG_DRIVE_STRENGTH,
        PIN_CONFIG_DRIVE_STRENGTH_UA,
        PIN_CONFIG_INPUT_DEBOUNCE,
        PIN_CONFIG_INPUT_ENABLE,
        PIN_CONFIG_INPUT_SCHMITT,
        PIN_CONFIG_INPUT_SCHMITT_ENABLE,
        PIN_CONFIG_LOW_POWER_MODE,
        PIN_CONFIG_OUTPUT_ENABLE,
        PIN_CONFIG_OUTPUT,
        PIN_CONFIG_POWER_SOURCE,
        PIN_CONFIG_SLEEP_HARDWARE_STATE,
        PIN_CONFIG_SLEW_RATE,
        PIN_CONFIG_SKEW_DELAY,
        PIN_CONFIG_END = 0x7F,
        PIN_CONFIG_MAX = 0xFF,
};

#if CONFIG_IS_ENABLED(PINCTRL_GENERIC)
/**
 * pinctrl_generic_set_state() - Generic set_state operation
 * @pctldev:    Pinctrl device to use
 * @config:     Config device (pseudo device), pointing a config node in DTS
 *
 * Parse the DT node of @config and its children and handle generic properties
 * such as "pins", "groups", "functions", and pin configuration parameters.
 *
 * Return: 0 on success, or negative error code on failure
 */
int pinctrl_generic_set_state(struct udevice *pctldev, struct udevice *config);
#else
static inline int pinctrl_generic_set_state(struct udevice *pctldev,
                                            struct udevice *config)
{
        return -EINVAL;
}
#endif

#if CONFIG_IS_ENABLED(PINCTRL)
/**
 * pinctrl_select_state() - Set a device to a given state
 * @dev:        Peripheral device
 * @statename:  State name, like "default"
 *
 * Return: 0 on success, or negative error code on failure
 */
int pinctrl_select_state(struct udevice *dev, const char *statename);
#else
static inline int pinctrl_select_state(struct udevice *dev,
                                       const char *statename)
{
        return -EINVAL;
}
#endif

/**
 * pinctrl_request() - Request a particular pinctrl function
 * @dev:        Pinctrl device to use
 * @func:       Function number (driver-specific)
 * @flags:      Flags (driver-specific)
 *
 * Return: 0 if OK, or negative error code on failure
 */
int pinctrl_request(struct udevice *dev, int func, int flags);

/**
 * pinctrl_request_noflags() - Request a particular pinctrl function
 * @dev:        Pinctrl device to use
 * @func:       Function number (driver-specific)
 *
 * This is similar to pinctrl_request() but uses 0 for @flags.
 *
 * Return: 0 if OK, or negative error code on failure
 */
int pinctrl_request_noflags(struct udevice *dev, int func);

/**
 * pinctrl_get_periph_id() - Get the peripheral ID for a device
 * @dev:        Pinctrl device to use for decoding
 * @periph:     Device to check
 *
 * This generally looks at the peripheral's device tree node to work out the
 * peripheral ID. The return value is normally interpreted as enum periph_id.
 * so long as this is defined by the platform (which it should be).
 *
 * Return: Peripheral ID of @periph, or -ENOENT on error
 */
int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph);

/**
 * pinctrl_get_gpio_mux() - get the mux value for a particular GPIO
 * @dev:        Pinctrl device to use
 * @banknum:    GPIO bank number
 * @index:      GPIO index within the bank
 *
 * This allows the raw mux value for a GPIO to be obtained. It is
 * useful for displaying the function being used by that GPIO, such
 * as with the 'gpio' command. This function is internal to the GPIO
 * subsystem and should not be used by generic code. Typically it is
 * used by a GPIO driver with knowledge of the SoC pinctrl setup.
 *
 * Return: Mux value (SoC-specific, e.g. 0 for input, 1 for output)
*/
int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index);

/**
 * pinctrl_get_pin_muxing() - Returns the muxing description
 * @dev:        Pinctrl device to use
 * @selector:   Pin index within pin-controller
 * @buf:        Pin's muxing description
 * @size:       Pin's muxing description length
 *
 * This allows to display the muxing description of the given pin for
 * debug purpose
 *
 * Return: 0 if OK, or negative error code on failure
 */
int pinctrl_get_pin_muxing(struct udevice *dev, int selector, char *buf,
                           int size);

/**
 * pinctrl_get_pins_count() - Display pin-controller pins number
 * @dev:        Pinctrl device to use
 *
 * This allows to know the number of pins owned by a given pin-controller
 *
 * Return: Number of pins if OK, or -ENOSYS when not supported
 */
int pinctrl_get_pins_count(struct udevice *dev);

/**
 * pinctrl_get_pin_name() - Returns the pin's name
 * @dev:        Pinctrl device to use
 * @selector:   Pin index within pin-controller
 * @buf:        Buffer to fill with the name of the pin
 * @size:       Size of @buf
 *
 * This allows to display the pin's name for debug purpose
 *
 * Return: 0 if OK, or negative error code on failure
 */
int pinctrl_get_pin_name(struct udevice *dev, int selector, char *buf,
                         int size);

/**
 * pinctrl_gpio_request() - Request a single pin to be used as GPIO
 * @dev:        GPIO peripheral device
 * @offset:     GPIO pin offset from the GPIO controller
 *
 * Return: 0 on success, or negative error code on failure
 */
int pinctrl_gpio_request(struct udevice *dev, unsigned offset);

/**
 * pinctrl_gpio_free() - Free a single pin used as GPIO
 * @dev:        GPIO peripheral device
 * @offset:     GPIO pin offset from the GPIO controller
 *
 * Return: 0 on success, or negative error code on failure
 */
int pinctrl_gpio_free(struct udevice *dev, unsigned offset);

#endif /* __PINCTRL_H */