1/* 2 * Interface the generic pinconfig portions of the pinctrl subsystem 3 * 4 * Copyright (C) 2011 ST-Ericsson SA 5 * Written on behalf of Linaro for ST-Ericsson 6 * This interface is used in the core to keep track of pins. 7 * 8 * Author: Linus Walleij <linus.walleij@linaro.org> 9 * 10 * License terms: GNU General Public License (GPL) version 2 11 */ 12#ifndef __LINUX_PINCTRL_PINCONF_GENERIC_H 13#define __LINUX_PINCTRL_PINCONF_GENERIC_H 14 15/* 16 * You shouldn't even be able to compile with these enums etc unless you're 17 * using generic pin config. That is why this is defined out. 18 */ 19#ifdef CONFIG_GENERIC_PINCONF 20 21/** 22 * enum pin_config_param - possible pin configuration parameters 23 * @PIN_CONFIG_BIAS_DISABLE: disable any pin bias on the pin, a 24 * transition from say pull-up to pull-down implies that you disable 25 * pull-up in the process, this setting disables all biasing. 26 * @PIN_CONFIG_BIAS_HIGH_IMPEDANCE: the pin will be set to a high impedance 27 * mode, also know as "third-state" (tristate) or "high-Z" or "floating". 28 * On output pins this effectively disconnects the pin, which is useful 29 * if for example some other pin is going to drive the signal connected 30 * to it for a while. Pins used for input are usually always high 31 * impedance. 32 * @PIN_CONFIG_BIAS_BUS_HOLD: the pin will be set to weakly latch so that it 33 * weakly drives the last value on a tristate bus, also known as a "bus 34 * holder", "bus keeper" or "repeater". This allows another device on the 35 * bus to change the value by driving the bus high or low and switching to 36 * tristate. The argument is ignored. 37 * @PIN_CONFIG_BIAS_PULL_UP: the pin will be pulled up (usually with high 38 * impedance to VDD). If the argument is != 0 pull-up is enabled, 39 * if it is 0, pull-up is total, i.e. the pin is connected to VDD. 40 * @PIN_CONFIG_BIAS_PULL_DOWN: the pin will be pulled down (usually with high 41 * impedance to GROUND). If the argument is != 0 pull-down is enabled, 42 * if it is 0, pull-down is total, i.e. the pin is connected to GROUND. 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_DRIVE_PUSH_PULL: the pin will be driven actively high and 52 * low, this is the most typical case and is typically achieved with two 53 * active transistors on the output. Setting this config will enable 54 * push-pull mode, the argument is ignored. 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_STRENGTH: the pin will sink or source at most the current 63 * passed as argument. The argument is in mA. 64 * @PIN_CONFIG_INPUT_ENABLE: enable the pin's input. Note that this does not 65 * affect the pin's ability to drive output. 1 enables input, 0 disables 66 * input. 67 * @PIN_CONFIG_INPUT_SCHMITT_ENABLE: control schmitt-trigger mode on the pin. 68 * If the argument != 0, schmitt-trigger mode is enabled. If it's 0, 69 * schmitt-trigger mode is disabled. 70 * @PIN_CONFIG_INPUT_SCHMITT: this will configure an input pin to run in 71 * schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis, 72 * the threshold value is given on a custom format as argument when 73 * setting pins to this mode. 74 * @PIN_CONFIG_INPUT_DEBOUNCE: this will configure the pin to debounce mode, 75 * which means it will wait for signals to settle when reading inputs. The 76 * argument gives the debounce time in usecs. Setting the 77 * argument to zero turns debouncing off. 78 * @PIN_CONFIG_POWER_SOURCE: if the pin can select between different power 79 * supplies, the argument to this parameter (on a custom format) tells 80 * the driver which alternative power source to use. 81 * @PIN_CONFIG_SLEW_RATE: if the pin can select slew rate, the argument to 82 * this parameter (on a custom format) tells the driver which alternative 83 * slew rate to use. 84 * @PIN_CONFIG_LOW_POWER_MODE: 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_OUTPUT: this will configure the pin as an output. Use argument 89 * 1 to indicate high level, argument 0 to indicate low level. (Please 90 * see Documentation/pinctrl.txt, section "GPIO mode pitfalls" for a 91 * discussion around this parameter.) 92 * @PIN_CONFIG_END: this is the last enumerator for pin configurations, if 93 * you need to pass in custom configurations to the pin controller, use 94 * PIN_CONFIG_END+1 as the base offset. 95 */ 96enum pin_config_param { 97 PIN_CONFIG_BIAS_DISABLE, 98 PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 99 PIN_CONFIG_BIAS_BUS_HOLD, 100 PIN_CONFIG_BIAS_PULL_UP, 101 PIN_CONFIG_BIAS_PULL_DOWN, 102 PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 103 PIN_CONFIG_DRIVE_PUSH_PULL, 104 PIN_CONFIG_DRIVE_OPEN_DRAIN, 105 PIN_CONFIG_DRIVE_OPEN_SOURCE, 106 PIN_CONFIG_DRIVE_STRENGTH, 107 PIN_CONFIG_INPUT_ENABLE, 108 PIN_CONFIG_INPUT_SCHMITT_ENABLE, 109 PIN_CONFIG_INPUT_SCHMITT, 110 PIN_CONFIG_INPUT_DEBOUNCE, 111 PIN_CONFIG_POWER_SOURCE, 112 PIN_CONFIG_SLEW_RATE, 113 PIN_CONFIG_LOW_POWER_MODE, 114 PIN_CONFIG_OUTPUT, 115 PIN_CONFIG_END = 0x7FFF, 116}; 117 118#ifdef CONFIG_DEBUG_FS 119#define PCONFDUMP(a, b, c, d) { .param = a, .display = b, .format = c, \ 120 .has_arg = d } 121 122struct pin_config_item { 123 const enum pin_config_param param; 124 const char * const display; 125 const char * const format; 126 bool has_arg; 127}; 128#endif /* CONFIG_DEBUG_FS */ 129 130/* 131 * Helpful configuration macro to be used in tables etc. 132 */ 133#define PIN_CONF_PACKED(p, a) ((a << 16) | ((unsigned long) p & 0xffffUL)) 134 135/* 136 * The following inlines stuffs a configuration parameter and data value 137 * into and out of an unsigned long argument, as used by the generic pin config 138 * system. We put the parameter in the lower 16 bits and the argument in the 139 * upper 16 bits. 140 */ 141 142static inline enum pin_config_param pinconf_to_config_param(unsigned long config) 143{ 144 return (enum pin_config_param) (config & 0xffffUL); 145} 146 147static inline u16 pinconf_to_config_argument(unsigned long config) 148{ 149 return (enum pin_config_param) ((config >> 16) & 0xffffUL); 150} 151 152static inline unsigned long pinconf_to_config_packed(enum pin_config_param param, 153 u16 argument) 154{ 155 return PIN_CONF_PACKED(param, argument); 156} 157 158#ifdef CONFIG_OF 159 160#include <linux/device.h> 161#include <linux/pinctrl/machine.h> 162struct pinctrl_dev; 163struct pinctrl_map; 164 165struct pinconf_generic_params { 166 const char * const property; 167 enum pin_config_param param; 168 u32 default_value; 169}; 170 171int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev, 172 struct device_node *np, struct pinctrl_map **map, 173 unsigned *reserved_maps, unsigned *num_maps, 174 enum pinctrl_map_type type); 175int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev, 176 struct device_node *np_config, struct pinctrl_map **map, 177 unsigned *num_maps, enum pinctrl_map_type type); 178 179static inline int pinconf_generic_dt_node_to_map_group( 180 struct pinctrl_dev *pctldev, struct device_node *np_config, 181 struct pinctrl_map **map, unsigned *num_maps) 182{ 183 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps, 184 PIN_MAP_TYPE_CONFIGS_GROUP); 185} 186 187static inline int pinconf_generic_dt_node_to_map_pin( 188 struct pinctrl_dev *pctldev, struct device_node *np_config, 189 struct pinctrl_map **map, unsigned *num_maps) 190{ 191 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps, 192 PIN_MAP_TYPE_CONFIGS_PIN); 193} 194 195static inline int pinconf_generic_dt_node_to_map_all( 196 struct pinctrl_dev *pctldev, struct device_node *np_config, 197 struct pinctrl_map **map, unsigned *num_maps) 198{ 199 /* 200 * passing the type as PIN_MAP_TYPE_INVALID causes the underlying parser 201 * to infer the map type from the DT properties used. 202 */ 203 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps, 204 PIN_MAP_TYPE_INVALID); 205} 206#endif 207 208#endif /* CONFIG_GENERIC_PINCONF */ 209 210#endif /* __LINUX_PINCTRL_PINCONF_GENERIC_H */ 211