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 */
96 enum 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 /*
119 * Helpful configuration macro to be used in tables etc.
120 */
121 #define PIN_CONF_PACKED(p, a) ((a << 16) | ((unsigned long) p & 0xffffUL))
122
123 /*
124 * The following inlines stuffs a configuration parameter and data value
125 * into and out of an unsigned long argument, as used by the generic pin config
126 * system. We put the parameter in the lower 16 bits and the argument in the
127 * upper 16 bits.
128 */
129
pinconf_to_config_param(unsigned long config)130 static inline enum pin_config_param pinconf_to_config_param(unsigned long config)
131 {
132 return (enum pin_config_param) (config & 0xffffUL);
133 }
134
pinconf_to_config_argument(unsigned long config)135 static inline u16 pinconf_to_config_argument(unsigned long config)
136 {
137 return (enum pin_config_param) ((config >> 16) & 0xffffUL);
138 }
139
pinconf_to_config_packed(enum pin_config_param param,u16 argument)140 static inline unsigned long pinconf_to_config_packed(enum pin_config_param param,
141 u16 argument)
142 {
143 return PIN_CONF_PACKED(param, argument);
144 }
145
146 #ifdef CONFIG_OF
147
148 #include <linux/device.h>
149 #include <linux/pinctrl/machine.h>
150 struct pinctrl_dev;
151 struct pinctrl_map;
152
153 int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev,
154 struct device_node *np, struct pinctrl_map **map,
155 unsigned *reserved_maps, unsigned *num_maps,
156 enum pinctrl_map_type type);
157 int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev,
158 struct device_node *np_config, struct pinctrl_map **map,
159 unsigned *num_maps, enum pinctrl_map_type type);
160
pinconf_generic_dt_node_to_map_group(struct pinctrl_dev * pctldev,struct device_node * np_config,struct pinctrl_map ** map,unsigned * num_maps)161 static inline int pinconf_generic_dt_node_to_map_group(
162 struct pinctrl_dev *pctldev, struct device_node *np_config,
163 struct pinctrl_map **map, unsigned *num_maps)
164 {
165 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps,
166 PIN_MAP_TYPE_CONFIGS_GROUP);
167 }
168
pinconf_generic_dt_node_to_map_pin(struct pinctrl_dev * pctldev,struct device_node * np_config,struct pinctrl_map ** map,unsigned * num_maps)169 static inline int pinconf_generic_dt_node_to_map_pin(
170 struct pinctrl_dev *pctldev, struct device_node *np_config,
171 struct pinctrl_map **map, unsigned *num_maps)
172 {
173 return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps,
174 PIN_MAP_TYPE_CONFIGS_PIN);
175 }
176
177 #endif
178
179 #endif /* CONFIG_GENERIC_PINCONF */
180
181 #endif /* __LINUX_PINCTRL_PINCONF_GENERIC_H */
182