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 | |
18 | struct device_node; |
19 | |
20 | struct pinctrl_dev; |
21 | struct 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 | */ |
119 | enum 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 | |
161 | static inline enum pin_config_param pinconf_to_config_param(unsigned long config) |
162 | { |
163 | return (enum pin_config_param) (config & 0xffUL); |
164 | } |
165 | |
166 | static inline u32 pinconf_to_config_argument(unsigned long config) |
167 | { |
168 | return (u32) ((config >> 8) & 0xffffffUL); |
169 | } |
170 | |
171 | static 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 | |
181 | struct 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 | |
188 | struct pinconf_generic_params { |
189 | const char * const property; |
190 | enum pin_config_param param; |
191 | u32 default_value; |
192 | }; |
193 | |
194 | int 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); |
198 | int 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); |
201 | void pinconf_generic_dt_free_map(struct pinctrl_dev *pctldev, |
202 | struct pinctrl_map *map, unsigned int num_maps); |
203 | |
204 | static 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 | type: PIN_MAP_TYPE_CONFIGS_GROUP); |
210 | } |
211 | |
212 | static 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 | type: PIN_MAP_TYPE_CONFIGS_PIN); |
218 | } |
219 | |
220 | static 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 | type: PIN_MAP_TYPE_INVALID); |
230 | } |
231 | |
232 | #endif /* __LINUX_PINCTRL_PINCONF_GENERIC_H */ |
233 | |