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/types.h> 15 16#include <linux/pinctrl/machine.h> 17 18struct device_node; 19 20struct pinctrl_dev; 21struct pinctrl_map; 22 23/** 24 * enum pin_config_param - possible pin configuration parameters 25 * @PIN_CONFIG_BIAS_BUS_HOLD: the pin will be set to weakly latch so that it 26 * weakly drives the last value on a tristate bus, also known as a "bus 27 * holder", "bus keeper" or "repeater". This allows another device on the 28 * bus to change the value by driving the bus high or low and switching to 29 * tristate. The argument is ignored. 30 * @PIN_CONFIG_BIAS_DISABLE: disable any pin bias on the pin, a 31 * transition from say pull-up to pull-down implies that you disable 32 * pull-up in the process, this setting disables all biasing. 33 * @PIN_CONFIG_BIAS_HIGH_IMPEDANCE: the pin will be set to a high impedance 34 * mode, also know as "third-state" (tristate) or "high-Z" or "floating". 35 * On output pins this effectively disconnects the pin, which is useful 36 * if for example some other pin is going to drive the signal connected 37 * to it for a while. Pins used for input are usually always high 38 * impedance. 39 * @PIN_CONFIG_BIAS_PULL_DOWN: the pin will be pulled down (usually with high 40 * impedance to GROUND). If the argument is != 0 pull-down is enabled, 41 * the value is interpreted by the driver and can be custom or an SI unit 42 * such as Ohms. 43 * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down based 44 * on embedded knowledge of the controller hardware, like current mux 45 * function. The pull direction and possibly strength too will normally 46 * be decided completely inside the hardware block and not be readable 47 * from the kernel side. 48 * If the argument is != 0 pull up/down is enabled, if it is 0, the 49 * configuration is ignored. The proper way to disable it is to use 50 * @PIN_CONFIG_BIAS_DISABLE. 51 * @PIN_CONFIG_BIAS_PULL_UP: the pin will be pulled up (usually with high 52 * impedance to VDD). If the argument is != 0 pull-up is enabled, 53 * the value is interpreted by the driver and can be custom or an SI unit 54 * such as Ohms. 55 * @PIN_CONFIG_DRIVE_OPEN_DRAIN: the pin will be driven with open drain (open 56 * collector) which means it is usually wired with other output ports 57 * which are then pulled up with an external resistor. Setting this 58 * config will enable open drain mode, the argument is ignored. 59 * @PIN_CONFIG_DRIVE_OPEN_SOURCE: the pin will be driven with open source 60 * (open emitter). Setting this config will enable open source mode, the 61 * argument is ignored. 62 * @PIN_CONFIG_DRIVE_PUSH_PULL: the pin will be driven actively high and 63 * low, this is the most typical case and is typically achieved with two 64 * active transistors on the output. Setting this config will enable 65 * push-pull mode, the argument is ignored. 66 * @PIN_CONFIG_DRIVE_STRENGTH: the pin will sink or source at most the current 67 * passed as argument. The argument is in mA. 68 * @PIN_CONFIG_DRIVE_STRENGTH_UA: the pin will sink or source at most the current 69 * passed as argument. The argument is in uA. 70 * @PIN_CONFIG_INPUT_DEBOUNCE: this will configure the pin to debounce mode, 71 * which means it will wait for signals to settle when reading inputs. The 72 * argument gives the debounce time in usecs. Setting the 73 * argument to zero turns debouncing off. 74 * @PIN_CONFIG_INPUT_ENABLE: enable the pin's input. Note that this does not 75 * affect the pin's ability to drive output. 1 enables input, 0 disables 76 * input. 77 * @PIN_CONFIG_INPUT_SCHMITT: this will configure an input pin to run in 78 * schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis, 79 * the threshold value is given on a custom format as argument when 80 * setting pins to this mode. 81 * @PIN_CONFIG_INPUT_SCHMITT_ENABLE: control schmitt-trigger mode on the pin. 82 * If the argument != 0, schmitt-trigger mode is enabled. If it's 0, 83 * schmitt-trigger mode is disabled. 84 * @PIN_CONFIG_MODE_LOW_POWER: this will configure the pin for low power 85 * operation, if several modes of operation are supported these can be 86 * passed in the argument on a custom form, else just use argument 1 87 * to indicate low power mode, argument 0 turns low power mode off. 88 * @PIN_CONFIG_MODE_PWM: this will configure the pin for PWM 89 * @PIN_CONFIG_OUTPUT: this will configure the pin as an output and drive a 90 * value on the line. Use argument 1 to indicate high level, argument 0 to 91 * indicate low level. (Please see Documentation/driver-api/pin-control.rst, 92 * section "GPIO mode pitfalls" for a discussion around this parameter.) 93 * @PIN_CONFIG_OUTPUT_ENABLE: this will enable the pin's output mode 94 * without driving a value there. For most platforms this reduces to 95 * enable the output buffers and then let the pin controller current 96 * configuration (eg. the currently selected mux function) drive values on 97 * the line. Use argument 1 to enable output mode, argument 0 to disable 98 * it. 99 * @PIN_CONFIG_OUTPUT_IMPEDANCE_OHMS: this will configure the output impedance 100 * of the pin with the value passed as argument. The argument is in ohms. 101 * @PIN_CONFIG_PERSIST_STATE: retain pin state across sleep or controller reset 102 * @PIN_CONFIG_POWER_SOURCE: if the pin can select between different power 103 * supplies, the argument to this parameter (on a custom format) tells 104 * the driver which alternative power source to use. 105 * @PIN_CONFIG_SKEW_DELAY: if the pin has programmable skew rate (on inputs) 106 * or latch delay (on outputs) this parameter (in a custom format) 107 * specifies the clock skew or latch delay. It typically controls how 108 * many double inverters are put in front of the line. 109 * @PIN_CONFIG_SLEEP_HARDWARE_STATE: indicate this is sleep related state. 110 * @PIN_CONFIG_SLEW_RATE: if the pin can select slew rate, the argument to 111 * this parameter (on a custom format) tells the driver which alternative 112 * slew rate to use. 113 * @PIN_CONFIG_END: this is the last enumerator for pin configurations, if 114 * you need to pass in custom configurations to the pin controller, use 115 * PIN_CONFIG_END+1 as the base offset. 116 * @PIN_CONFIG_MAX: this is the maximum configuration value that can be 117 * presented using the packed format. 118 */ 119enum pin_config_param { 120 PIN_CONFIG_BIAS_BUS_HOLD, 121 PIN_CONFIG_BIAS_DISABLE, 122 PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 123 PIN_CONFIG_BIAS_PULL_DOWN, 124 PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 125 PIN_CONFIG_BIAS_PULL_UP, 126 PIN_CONFIG_DRIVE_OPEN_DRAIN, 127 PIN_CONFIG_DRIVE_OPEN_SOURCE, 128 PIN_CONFIG_DRIVE_PUSH_PULL, 129 PIN_CONFIG_DRIVE_STRENGTH, 130 PIN_CONFIG_DRIVE_STRENGTH_UA, 131 PIN_CONFIG_INPUT_DEBOUNCE, 132 PIN_CONFIG_INPUT_ENABLE, 133 PIN_CONFIG_INPUT_SCHMITT, 134 PIN_CONFIG_INPUT_SCHMITT_ENABLE, 135 PIN_CONFIG_MODE_LOW_POWER, 136 PIN_CONFIG_MODE_PWM, 137 PIN_CONFIG_OUTPUT, 138 PIN_CONFIG_OUTPUT_ENABLE, 139 PIN_CONFIG_OUTPUT_IMPEDANCE_OHMS, 140 PIN_CONFIG_PERSIST_STATE, 141 PIN_CONFIG_POWER_SOURCE, 142 PIN_CONFIG_SKEW_DELAY, 143 PIN_CONFIG_SLEEP_HARDWARE_STATE, 144 PIN_CONFIG_SLEW_RATE, 145 PIN_CONFIG_END = 0x7F, 146 PIN_CONFIG_MAX = 0xFF, 147}; 148 149/* 150 * Helpful configuration macro to be used in tables etc. 151 */ 152#define PIN_CONF_PACKED(p, a) ((a << 8) | ((unsigned long) p & 0xffUL)) 153 154/* 155 * The following inlines stuffs a configuration parameter and data value 156 * into and out of an unsigned long argument, as used by the generic pin config 157 * system. We put the parameter in the lower 8 bits and the argument in the 158 * upper 24 bits. 159 */ 160 161static inline enum pin_config_param pinconf_to_config_param(unsigned long config) 162{ 163 return (enum pin_config_param) (config & 0xffUL); 164} 165 166static inline u32 pinconf_to_config_argument(unsigned long config) 167{ 168 return (u32) ((config >> 8) & 0xffffffUL); 169} 170 171static inline unsigned long pinconf_to_config_packed(enum pin_config_param param, 172 u32 argument) 173{ 174 return PIN_CONF_PACKED(param, argument); 175} 176 177#define PCONFDUMP(a, b, c, d) { \ 178 .param = a, .display = b, .format = c, .has_arg = d \ 179 } 180 181struct pin_config_item { 182 const enum pin_config_param param; 183 const char * const display; 184 const char * const format; 185 bool has_arg; 186}; 187 188struct pinconf_generic_params { 189 const char * const property; 190 enum pin_config_param param; 191 u32 default_value; 192}; 193 194int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev, 195 struct device_node *np, struct pinctrl_map **map, 196 unsigned int *reserved_maps, unsigned int *num_maps, 197 enum pinctrl_map_type type); 198int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev, 199 struct device_node *np_config, struct pinctrl_map **map, 200 unsigned int *num_maps, enum pinctrl_map_type type); 201void pinconf_generic_dt_free_map(struct pinctrl_dev *pctldev, 202 struct pinctrl_map *map, unsigned int num_maps); 203 204static inline int pinconf_generic_dt_node_to_map_group(struct pinctrl_dev *pctldev, 205 struct device_node *np_config, struct pinctrl_map **map, 206 unsigned int *num_maps) 207{ 208 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps, 209 PIN_MAP_TYPE_CONFIGS_GROUP); 210} 211 212static inline int pinconf_generic_dt_node_to_map_pin(struct pinctrl_dev *pctldev, 213 struct device_node *np_config, struct pinctrl_map **map, 214 unsigned int *num_maps) 215{ 216 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps, 217 PIN_MAP_TYPE_CONFIGS_PIN); 218} 219 220static inline int pinconf_generic_dt_node_to_map_all(struct pinctrl_dev *pctldev, 221 struct device_node *np_config, struct pinctrl_map **map, 222 unsigned *num_maps) 223{ 224 /* 225 * passing the type as PIN_MAP_TYPE_INVALID causes the underlying parser 226 * to infer the map type from the DT properties used. 227 */ 228 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps, 229 PIN_MAP_TYPE_INVALID); 230} 231 232#endif /* __LINUX_PINCTRL_PINCONF_GENERIC_H */ 233