/* SPDX-License-Identifier: GPL-2.0-only */ /* * Interface the generic pinconfig portions of the pinctrl subsystem * * Copyright (C) 2011 ST-Ericsson SA * Written on behalf of Linaro for ST-Ericsson * This interface is used in the core to keep track of pins. * * Author: Linus Walleij <[email protected]> */ #ifndef __LINUX_PINCTRL_PINCONF_GENERIC_H #define __LINUX_PINCTRL_PINCONF_GENERIC_H #include <linux/types.h> #include <linux/pinctrl/machine.h> struct device_node; struct pinctrl_dev; struct pinctrl_map; /** * enum pin_config_param - possible 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, * the value is interpreted by the driver and can be custom or an SI unit * such as Ohms. * @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, * the value is interpreted by the driver and can be custom or an SI unit * such as Ohms. * @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_MODE_LOW_POWER: 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_MODE_PWM: this will configure the pin for PWM * @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/pin-control.rst, * section "GPIO mode pitfalls" for a discussion around this parameter.) * @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_IMPEDANCE_OHMS: this will configure the output impedance * of the pin with the value passed as argument. The argument is in ohms. * @PIN_CONFIG_PERSIST_STATE: retain pin state across sleep or controller reset * @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_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_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_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 { … }; /* * Helpful configuration macro to be used in tables etc. */ #define PIN_CONF_PACKED(p, a) … /* * The following inlines stuffs a configuration parameter and data value * into and out of an unsigned long argument, as used by the generic pin config * system. We put the parameter in the lower 8 bits and the argument in the * upper 24 bits. */ static inline enum pin_config_param pinconf_to_config_param(unsigned long config) { … } static inline u32 pinconf_to_config_argument(unsigned long config) { … } static inline unsigned long pinconf_to_config_packed(enum pin_config_param param, u32 argument) { … } #define PCONFDUMP(a, b, c, d) … struct pin_config_item { … }; struct pinconf_generic_params { … }; int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev, struct device_node *np, struct pinctrl_map **map, unsigned int *reserved_maps, unsigned int *num_maps, enum pinctrl_map_type type); int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev, struct device_node *np_config, struct pinctrl_map **map, unsigned int *num_maps, enum pinctrl_map_type type); void pinconf_generic_dt_free_map(struct pinctrl_dev *pctldev, struct pinctrl_map *map, unsigned int num_maps); static inline int pinconf_generic_dt_node_to_map_group(struct pinctrl_dev *pctldev, struct device_node *np_config, struct pinctrl_map **map, unsigned int *num_maps) { … } static inline int pinconf_generic_dt_node_to_map_pin(struct pinctrl_dev *pctldev, struct device_node *np_config, struct pinctrl_map **map, unsigned int *num_maps) { … } static inline int pinconf_generic_dt_node_to_map_all(struct pinctrl_dev *pctldev, struct device_node *np_config, struct pinctrl_map **map, unsigned *num_maps) { … } #endif /* __LINUX_PINCTRL_PINCONF_GENERIC_H */
Codebase Browser
linux