1/* SPDX-License-Identifier: GPL-2.0-only */ 2/* 3 * Interface the generic pinconfig portions of the pinctrl subsystem 4 * 5 * Copyright (C) 2011 ST-Ericsson SA 6 * Written on behalf of Linaro for ST-Ericsson 7 * This interface is used in the core to keep track of pins. 8 * 9 * Author: Linus Walleij <linus.walleij@linaro.org> 10 */ 11#ifndef __LINUX_PINCTRL_PINCONF_GENERIC_H 12#define __LINUX_PINCTRL_PINCONF_GENERIC_H 13 14#include <linux/device.h> 15#include <linux/pinctrl/machine.h> 16 17struct pinctrl_dev; 18struct pinctrl_map; 19 20/** 21 * enum pin_config_param - possible pin configuration parameters 22 * @PIN_CONFIG_BIAS_BUS_HOLD: the pin will be set to weakly latch so that it 23 * weakly drives the last value on a tristate bus, also known as a "bus 24 * holder", "bus keeper" or "repeater". This allows another device on the 25 * bus to change the value by driving the bus high or low and switching to 26 * tristate. The argument is ignored. 27 * @PIN_CONFIG_BIAS_DISABLE: disable any pin bias on the pin, a 28 * transition from say pull-up to pull-down implies that you disable 29 * pull-up in the process, this setting disables all biasing. 30 * @PIN_CONFIG_BIAS_HIGH_IMPEDANCE: the pin will be set to a high impedance 31 * mode, also know as "third-state" (tristate) or "high-Z" or "floating". 32 * On output pins this effectively disconnects the pin, which is useful 33 * if for example some other pin is going to drive the signal connected 34 * to it for a while. Pins used for input are usually always high 35 * impedance. 36 * @PIN_CONFIG_BIAS_PULL_DOWN: the pin will be pulled down (usually with high 37 * impedance to GROUND). If the argument is != 0 pull-down is enabled, 38 * if it is 0, pull-down is total, i.e. the pin is connected to GROUND. 39 * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down based 40 * on embedded knowledge of the controller hardware, like current mux 41 * function. The pull direction and possibly strength too will normally 42 * be decided completely inside the hardware block and not be readable 43 * from the kernel side. 44 * If the argument is != 0 pull up/down is enabled, if it is 0, the 45 * configuration is ignored. The proper way to disable it is to use 46 * @PIN_CONFIG_BIAS_DISABLE. 47 * @PIN_CONFIG_BIAS_PULL_UP: the pin will be pulled up (usually with high 48 * impedance to VDD). If the argument is != 0 pull-up is enabled, 49 * if it is 0, pull-up is total, i.e. the pin is connected to VDD. 50 * @PIN_CONFIG_DRIVE_OPEN_DRAIN: the pin will be driven with open drain (open 51 * collector) which means it is usually wired with other output ports 52 * which are then pulled up with an external resistor. Setting this 53 * config will enable open drain mode, the argument is ignored. 54 * @PIN_CONFIG_DRIVE_OPEN_SOURCE: the pin will be driven with open source 55 * (open emitter). Setting this config will enable open source mode, the 56 * argument is ignored. 57 * @PIN_CONFIG_DRIVE_PUSH_PULL: the pin will be driven actively high and 58 * low, this is the most typical case and is typically achieved with two 59 * active transistors on the output. Setting this config will enable 60 * push-pull mode, the argument is ignored. 61 * @PIN_CONFIG_DRIVE_STRENGTH: the pin will sink or source at most the current 62 * passed as argument. The argument is in mA. 63 * @PIN_CONFIG_DRIVE_STRENGTH_UA: the pin will sink or source at most the current 64 * passed as argument. The argument is in uA. 65 * @PIN_CONFIG_INPUT_DEBOUNCE: this will configure the pin to debounce mode, 66 * which means it will wait for signals to settle when reading inputs. The 67 * argument gives the debounce time in usecs. Setting the 68 * argument to zero turns debouncing off. 69 * @PIN_CONFIG_INPUT_ENABLE: enable the pin's input. Note that this does not 70 * affect the pin's ability to drive output. 1 enables input, 0 disables 71 * input. 72 * @PIN_CONFIG_INPUT_SCHMITT: this will configure an input pin to run in 73 * schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis, 74 * the threshold value is given on a custom format as argument when 75 * setting pins to this mode. 76 * @PIN_CONFIG_INPUT_SCHMITT_ENABLE: control schmitt-trigger mode on the pin. 77 * If the argument != 0, schmitt-trigger mode is enabled. If it's 0, 78 * schmitt-trigger mode is disabled. 79 * @PIN_CONFIG_MODE_LOW_POWER: this will configure the pin for low power 80 * operation, if several modes of operation are supported these can be 81 * passed in the argument on a custom form, else just use argument 1 82 * to indicate low power mode, argument 0 turns low power mode off. 83 * @PIN_CONFIG_MODE_PWM: this will configure the pin for PWM 84 * @PIN_CONFIG_OUTPUT: this will configure the pin as an output and drive a 85 * value on the line. Use argument 1 to indicate high level, argument 0 to 86 * indicate low level. (Please see Documentation/driver-api/pin-control.rst, 87 * section "GPIO mode pitfalls" for a discussion around this parameter.) 88 * @PIN_CONFIG_OUTPUT_ENABLE: this will enable the pin's output mode 89 * without driving a value there. For most platforms this reduces to 90 * enable the output buffers and then let the pin controller current 91 * configuration (eg. the currently selected mux function) drive values on 92 * the line. Use argument 1 to enable output mode, argument 0 to disable 93 * it. 94 * @PIN_CONFIG_PERSIST_STATE: retain pin state across sleep or controller reset 95 * @PIN_CONFIG_POWER_SOURCE: if the pin can select between different power 96 * supplies, the argument to this parameter (on a custom format) tells 97 * the driver which alternative power source to use. 98 * @PIN_CONFIG_SKEW_DELAY: if the pin has programmable skew rate (on inputs) 99 * or latch delay (on outputs) this parameter (in a custom format) 100 * specifies the clock skew or latch delay. It typically controls how 101 * many double inverters are put in front of the line. 102 * @PIN_CONFIG_SLEEP_HARDWARE_STATE: indicate this is sleep related state. 103 * @PIN_CONFIG_SLEW_RATE: if the pin can select slew rate, the argument to 104 * this parameter (on a custom format) tells the driver which alternative 105 * slew rate to use. 106 * @PIN_CONFIG_END: this is the last enumerator for pin configurations, if 107 * you need to pass in custom configurations to the pin controller, use 108 * PIN_CONFIG_END+1 as the base offset. 109 * @PIN_CONFIG_MAX: this is the maximum configuration value that can be 110 * presented using the packed format. 111 */ 112enum pin_config_param { 113 PIN_CONFIG_BIAS_BUS_HOLD, 114 PIN_CONFIG_BIAS_DISABLE, 115 PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 116 PIN_CONFIG_BIAS_PULL_DOWN, 117 PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 118 PIN_CONFIG_BIAS_PULL_UP, 119 PIN_CONFIG_DRIVE_OPEN_DRAIN, 120 PIN_CONFIG_DRIVE_OPEN_SOURCE, 121 PIN_CONFIG_DRIVE_PUSH_PULL, 122 PIN_CONFIG_DRIVE_STRENGTH, 123 PIN_CONFIG_DRIVE_STRENGTH_UA, 124 PIN_CONFIG_INPUT_DEBOUNCE, 125 PIN_CONFIG_INPUT_ENABLE, 126 PIN_CONFIG_INPUT_SCHMITT, 127 PIN_CONFIG_INPUT_SCHMITT_ENABLE, 128 PIN_CONFIG_MODE_LOW_POWER, 129 PIN_CONFIG_MODE_PWM, 130 PIN_CONFIG_OUTPUT, 131 PIN_CONFIG_OUTPUT_ENABLE, 132 PIN_CONFIG_PERSIST_STATE, 133 PIN_CONFIG_POWER_SOURCE, 134 PIN_CONFIG_SKEW_DELAY, 135 PIN_CONFIG_SLEEP_HARDWARE_STATE, 136 PIN_CONFIG_SLEW_RATE, 137 PIN_CONFIG_END = 0x7F, 138 PIN_CONFIG_MAX = 0xFF, 139}; 140 141/* 142 * Helpful configuration macro to be used in tables etc. 143 */ 144#define PIN_CONF_PACKED(p, a) ((a << 8) | ((unsigned long) p & 0xffUL)) 145 146/* 147 * The following inlines stuffs a configuration parameter and data value 148 * into and out of an unsigned long argument, as used by the generic pin config 149 * system. We put the parameter in the lower 8 bits and the argument in the 150 * upper 24 bits. 151 */ 152 153static inline enum pin_config_param pinconf_to_config_param(unsigned long config) 154{ 155 return (enum pin_config_param) (config & 0xffUL); 156} 157 158static inline u32 pinconf_to_config_argument(unsigned long config) 159{ 160 return (u32) ((config >> 8) & 0xffffffUL); 161} 162 163static inline unsigned long pinconf_to_config_packed(enum pin_config_param param, 164 u32 argument) 165{ 166 return PIN_CONF_PACKED(param, argument); 167} 168 169#define PCONFDUMP(a, b, c, d) { \ 170 .param = a, .display = b, .format = c, .has_arg = d \ 171 } 172 173struct pin_config_item { 174 const enum pin_config_param param; 175 const char * const display; 176 const char * const format; 177 bool has_arg; 178}; 179 180struct pinconf_generic_params { 181 const char * const property; 182 enum pin_config_param param; 183 u32 default_value; 184}; 185 186int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev, 187 struct device_node *np, struct pinctrl_map **map, 188 unsigned *reserved_maps, unsigned *num_maps, 189 enum pinctrl_map_type type); 190int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev, 191 struct device_node *np_config, struct pinctrl_map **map, 192 unsigned *num_maps, enum pinctrl_map_type type); 193void pinconf_generic_dt_free_map(struct pinctrl_dev *pctldev, 194 struct pinctrl_map *map, unsigned num_maps); 195 196static inline int pinconf_generic_dt_node_to_map_group( 197 struct pinctrl_dev *pctldev, struct device_node *np_config, 198 struct pinctrl_map **map, unsigned *num_maps) 199{ 200 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps, 201 PIN_MAP_TYPE_CONFIGS_GROUP); 202} 203 204static inline int pinconf_generic_dt_node_to_map_pin( 205 struct pinctrl_dev *pctldev, struct device_node *np_config, 206 struct pinctrl_map **map, unsigned *num_maps) 207{ 208 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps, 209 PIN_MAP_TYPE_CONFIGS_PIN); 210} 211 212static inline int pinconf_generic_dt_node_to_map_all( 213 struct pinctrl_dev *pctldev, struct device_node *np_config, 214 struct pinctrl_map **map, unsigned *num_maps) 215{ 216 /* 217 * passing the type as PIN_MAP_TYPE_INVALID causes the underlying parser 218 * to infer the map type from the DT properties used. 219 */ 220 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps, 221 PIN_MAP_TYPE_INVALID); 222} 223 224#endif /* __LINUX_PINCTRL_PINCONF_GENERIC_H */ 225