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 <[email protected]> 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 drain 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_SCHMITT_ENABLE: control schmitt-trigger mode on the pin. 65 * If the argument != 0, schmitt-trigger mode is enabled. If it's 0, 66 * schmitt-trigger mode is disabled. 67 * @PIN_CONFIG_INPUT_SCHMITT: this will configure an input pin to run in 68 * schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis, 69 * the threshold value is given on a custom format as argument when 70 * setting pins to this mode. 71 * @PIN_CONFIG_INPUT_DEBOUNCE: this will configure the pin to debounce mode, 72 * which means it will wait for signals to settle when reading inputs. The 73 * argument gives the debounce time in usecs. Setting the 74 * argument to zero turns debouncing off. 75 * @PIN_CONFIG_POWER_SOURCE: if the pin can select between different power 76 * supplies, the argument to this parameter (on a custom format) tells 77 * the driver which alternative power source to use. 78 * @PIN_CONFIG_SLEW_RATE: if the pin can select slew rate, the argument to 79 * this parameter (on a custom format) tells the driver which alternative 80 * slew rate to use. 81 * @PIN_CONFIG_LOW_POWER_MODE: this will configure the pin for low power 82 * operation, if several modes of operation are supported these can be 83 * passed in the argument on a custom form, else just use argument 1 84 * to indicate low power mode, argument 0 turns low power mode off. 85 * @PIN_CONFIG_OUTPUT: this will configure the pin in output, use argument 86 * 1 to indicate high level, argument 0 to indicate low level. 87 * @PIN_CONFIG_END: this is the last enumerator for pin configurations, if 88 * you need to pass in custom configurations to the pin controller, use 89 * PIN_CONFIG_END+1 as the base offset. 90 */ 91 enum pin_config_param { 92 PIN_CONFIG_BIAS_DISABLE, 93 PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 94 PIN_CONFIG_BIAS_BUS_HOLD, 95 PIN_CONFIG_BIAS_PULL_UP, 96 PIN_CONFIG_BIAS_PULL_DOWN, 97 PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 98 PIN_CONFIG_DRIVE_PUSH_PULL, 99 PIN_CONFIG_DRIVE_OPEN_DRAIN, 100 PIN_CONFIG_DRIVE_OPEN_SOURCE, 101 PIN_CONFIG_DRIVE_STRENGTH, 102 PIN_CONFIG_INPUT_SCHMITT_ENABLE, 103 PIN_CONFIG_INPUT_SCHMITT, 104 PIN_CONFIG_INPUT_DEBOUNCE, 105 PIN_CONFIG_POWER_SOURCE, 106 PIN_CONFIG_SLEW_RATE, 107 PIN_CONFIG_LOW_POWER_MODE, 108 PIN_CONFIG_OUTPUT, 109 PIN_CONFIG_END = 0x7FFF, 110 }; 111 112 /* 113 * Helpful configuration macro to be used in tables etc. 114 */ 115 #define PIN_CONF_PACKED(p, a) ((a << 16) | ((unsigned long) p & 0xffffUL)) 116 117 /* 118 * The following inlines stuffs a configuration parameter and data value 119 * into and out of an unsigned long argument, as used by the generic pin config 120 * system. We put the parameter in the lower 16 bits and the argument in the 121 * upper 16 bits. 122 */ 123 124 static inline enum pin_config_param pinconf_to_config_param(unsigned long config) 125 { 126 return (enum pin_config_param) (config & 0xffffUL); 127 } 128 129 static inline u16 pinconf_to_config_argument(unsigned long config) 130 { 131 return (enum pin_config_param) ((config >> 16) & 0xffffUL); 132 } 133 134 static inline unsigned long pinconf_to_config_packed(enum pin_config_param param, 135 u16 argument) 136 { 137 return PIN_CONF_PACKED(param, argument); 138 } 139 140 #ifdef CONFIG_OF 141 142 #include <linux/device.h> 143 #include <linux/pinctrl/machine.h> 144 struct pinctrl_dev; 145 struct pinctrl_map; 146 147 int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev, 148 struct device_node *np, struct pinctrl_map **map, 149 unsigned *reserved_maps, unsigned *num_maps, 150 enum pinctrl_map_type type); 151 int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev, 152 struct device_node *np_config, struct pinctrl_map **map, 153 unsigned *num_maps, enum pinctrl_map_type type); 154 155 static inline int pinconf_generic_dt_node_to_map_group( 156 struct pinctrl_dev *pctldev, struct device_node *np_config, 157 struct pinctrl_map **map, unsigned *num_maps) 158 { 159 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps, 160 PIN_MAP_TYPE_CONFIGS_GROUP); 161 } 162 163 static inline int pinconf_generic_dt_node_to_map_pin( 164 struct pinctrl_dev *pctldev, struct device_node *np_config, 165 struct pinctrl_map **map, unsigned *num_maps) 166 { 167 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps, 168 PIN_MAP_TYPE_CONFIGS_PIN); 169 } 170 171 #endif 172 173 #endif /* CONFIG_GENERIC_PINCONF */ 174 175 #endif /* __LINUX_PINCTRL_PINCONF_GENERIC_H */ 176