1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3 * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
4 */
5
6 #ifndef __PINCTRL_H
7 #define __PINCTRL_H
8
9 /**
10 * struct pinconf_param - pin config parameters
11 *
12 * @property: property name in DT nodes
13 * @param: ID for this config parameter
14 * @default_value: default value for this config parameter used in case
15 * no value is specified in DT nodes
16 */
17 struct pinconf_param {
18 const char * const property;
19 unsigned int param;
20 u32 default_value;
21 };
22
23 /**
24 * struct pinctrl_ops - pin control operations, to be implemented by
25 * pin controller drivers.
26 *
27 * The @set_state is the only mandatory operation. You can implement your
28 * pinctrl driver with its own @set_state. In this case, the other callbacks
29 * are not required. Otherwise, generic pinctrl framework is also available;
30 * use pinctrl_generic_set_state for @set_state, and implement other operations
31 * depending on your necessity.
32 *
33 * @get_pins_count: return number of selectable named pins available
34 * in this driver. (necessary to parse "pins" property in DTS)
35 * @get_pin_name: return the pin name of the pin selector,
36 * called by the core to figure out which pin it shall do
37 * operations to. (necessary to parse "pins" property in DTS)
38 * @get_groups_count: return number of selectable named groups available
39 * in this driver. (necessary to parse "groups" property in DTS)
40 * @get_group_name: return the group name of the group selector,
41 * called by the core to figure out which pin group it shall do
42 * operations to. (necessary to parse "groups" property in DTS)
43 * @get_functions_count: return number of selectable named functions available
44 * in this driver. (necessary for pin-muxing)
45 * @get_function_name: return the function name of the muxing selector,
46 * called by the core to figure out which mux setting it shall map a
47 * certain device to. (necessary for pin-muxing)
48 * @pinmux_set: enable a certain muxing function with a certain pin.
49 * The @func_selector selects a certain function whereas @pin_selector
50 * selects a certain pin to be used. On simple controllers one of them
51 * may be ignored. (necessary for pin-muxing against a single pin)
52 * @pinmux_group_set: enable a certain muxing function with a certain pin
53 * group. The @func_selector selects a certain function whereas
54 * @group_selector selects a certain set of pins to be used. On simple
55 * controllers one of them may be ignored.
56 * (necessary for pin-muxing against a pin group)
57 * @pinconf_num_params: number of driver-specific parameters to be parsed
58 * from device trees (necessary for pin-configuration)
59 * @pinconf_params: list of driver_specific parameters to be parsed from
60 * device trees (necessary for pin-configuration)
61 * @pinconf_set: configure an individual pin with a given parameter.
62 * (necessary for pin-configuration against a single pin)
63 * @pinconf_group_set: configure all pins in a group with a given parameter.
64 * (necessary for pin-configuration against a pin group)
65 * @set_state: do pinctrl operations specified by @config, a pseudo device
66 * pointing a config node. (necessary for pinctrl_full)
67 * @set_state_simple: do needed pinctrl operations for a peripherl @periph.
68 * (necessary for pinctrl_simple)
69 */
70 struct pinctrl_ops {
71 int (*get_pins_count)(struct udevice *dev);
72 const char *(*get_pin_name)(struct udevice *dev, unsigned selector);
73 int (*get_groups_count)(struct udevice *dev);
74 const char *(*get_group_name)(struct udevice *dev, unsigned selector);
75 int (*get_functions_count)(struct udevice *dev);
76 const char *(*get_function_name)(struct udevice *dev,
77 unsigned selector);
78 int (*pinmux_set)(struct udevice *dev, unsigned pin_selector,
79 unsigned func_selector);
80 int (*pinmux_group_set)(struct udevice *dev, unsigned group_selector,
81 unsigned func_selector);
82 unsigned int pinconf_num_params;
83 const struct pinconf_param *pinconf_params;
84 int (*pinconf_set)(struct udevice *dev, unsigned pin_selector,
85 unsigned param, unsigned argument);
86 int (*pinconf_group_set)(struct udevice *dev, unsigned group_selector,
87 unsigned param, unsigned argument);
88 int (*set_state)(struct udevice *dev, struct udevice *config);
89
90 /* for pinctrl-simple */
91 int (*set_state_simple)(struct udevice *dev, struct udevice *periph);
92 /**
93 * request() - Request a particular pinctrl function
94 *
95 * This activates the selected function.
96 *
97 * @dev: Device to adjust (UCLASS_PINCTRL)
98 * @func: Function number (driver-specific)
99 * @return 0 if OK, -ve on error
100 */
101 int (*request)(struct udevice *dev, int func, int flags);
102
103 /**
104 * get_periph_id() - get the peripheral ID for a device
105 *
106 * This generally looks at the peripheral's device tree node to work
107 * out the peripheral ID. The return value is normally interpreted as
108 * enum periph_id. so long as this is defined by the platform (which it
109 * should be).
110 *
111 * @dev: Pinctrl device to use for decoding
112 * @periph: Device to check
113 * @return peripheral ID of @periph, or -ENOENT on error
114 */
115 int (*get_periph_id)(struct udevice *dev, struct udevice *periph);
116
117 /**
118 * get_gpio_mux() - get the mux value for a particular GPIO
119 *
120 * This allows the raw mux value for a GPIO to be obtained. It is
121 * useful for displaying the function being used by that GPIO, such
122 * as with the 'gpio' command. This function is internal to the GPIO
123 * subsystem and should not be used by generic code. Typically it is
124 * used by a GPIO driver with knowledge of the SoC pinctrl setup.
125 *
126 * @dev: Pinctrl device to use
127 * @banknum: GPIO bank number
128 * @index: GPIO index within the bank
129 * @return mux value (SoC-specific, e.g. 0 for input, 1 for output)
130 */
131 int (*get_gpio_mux)(struct udevice *dev, int banknum, int index);
132 };
133
134 #define pinctrl_get_ops(dev) ((struct pinctrl_ops *)(dev)->driver->ops)
135
136 /**
137 * Generic pin configuration paramters
138 *
139 * enum pin_config_param - possible pin configuration parameters
140 * @PIN_CONFIG_BIAS_BUS_HOLD: the pin will be set to weakly latch so that it
141 * weakly drives the last value on a tristate bus, also known as a "bus
142 * holder", "bus keeper" or "repeater". This allows another device on the
143 * bus to change the value by driving the bus high or low and switching to
144 * tristate. The argument is ignored.
145 * @PIN_CONFIG_BIAS_DISABLE: disable any pin bias on the pin, a
146 * transition from say pull-up to pull-down implies that you disable
147 * pull-up in the process, this setting disables all biasing.
148 * @PIN_CONFIG_BIAS_HIGH_IMPEDANCE: the pin will be set to a high impedance
149 * mode, also know as "third-state" (tristate) or "high-Z" or "floating".
150 * On output pins this effectively disconnects the pin, which is useful
151 * if for example some other pin is going to drive the signal connected
152 * to it for a while. Pins used for input are usually always high
153 * impedance.
154 * @PIN_CONFIG_BIAS_PULL_DOWN: the pin will be pulled down (usually with high
155 * impedance to GROUND). If the argument is != 0 pull-down is enabled,
156 * if it is 0, pull-down is total, i.e. the pin is connected to GROUND.
157 * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down based
158 * on embedded knowledge of the controller hardware, like current mux
159 * function. The pull direction and possibly strength too will normally
160 * be decided completely inside the hardware block and not be readable
161 * from the kernel side.
162 * If the argument is != 0 pull up/down is enabled, if it is 0, the
163 * configuration is ignored. The proper way to disable it is to use
164 * @PIN_CONFIG_BIAS_DISABLE.
165 * @PIN_CONFIG_BIAS_PULL_UP: the pin will be pulled up (usually with high
166 * impedance to VDD). If the argument is != 0 pull-up is enabled,
167 * if it is 0, pull-up is total, i.e. the pin is connected to VDD.
168 * @PIN_CONFIG_DRIVE_OPEN_DRAIN: the pin will be driven with open drain (open
169 * collector) which means it is usually wired with other output ports
170 * which are then pulled up with an external resistor. Setting this
171 * config will enable open drain mode, the argument is ignored.
172 * @PIN_CONFIG_DRIVE_OPEN_SOURCE: the pin will be driven with open source
173 * (open emitter). Setting this config will enable open source mode, the
174 * argument is ignored.
175 * @PIN_CONFIG_DRIVE_PUSH_PULL: the pin will be driven actively high and
176 * low, this is the most typical case and is typically achieved with two
177 * active transistors on the output. Setting this config will enable
178 * push-pull mode, the argument is ignored.
179 * @PIN_CONFIG_DRIVE_STRENGTH: the pin will sink or source at most the current
180 * passed as argument. The argument is in mA.
181 * @PIN_CONFIG_INPUT_DEBOUNCE: this will configure the pin to debounce mode,
182 * which means it will wait for signals to settle when reading inputs. The
183 * argument gives the debounce time in usecs. Setting the
184 * argument to zero turns debouncing off.
185 * @PIN_CONFIG_INPUT_ENABLE: enable the pin's input. Note that this does not
186 * affect the pin's ability to drive output. 1 enables input, 0 disables
187 * input.
188 * @PIN_CONFIG_INPUT_SCHMITT: this will configure an input pin to run in
189 * schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis,
190 * the threshold value is given on a custom format as argument when
191 * setting pins to this mode.
192 * @PIN_CONFIG_INPUT_SCHMITT_ENABLE: control schmitt-trigger mode on the pin.
193 * If the argument != 0, schmitt-trigger mode is enabled. If it's 0,
194 * schmitt-trigger mode is disabled.
195 * @PIN_CONFIG_LOW_POWER_MODE: this will configure the pin for low power
196 * operation, if several modes of operation are supported these can be
197 * passed in the argument on a custom form, else just use argument 1
198 * to indicate low power mode, argument 0 turns low power mode off.
199 * @PIN_CONFIG_OUTPUT_ENABLE: this will enable the pin's output mode
200 * without driving a value there. For most platforms this reduces to
201 * enable the output buffers and then let the pin controller current
202 * configuration (eg. the currently selected mux function) drive values on
203 * the line. Use argument 1 to enable output mode, argument 0 to disable
204 * it.
205 * @PIN_CONFIG_OUTPUT: this will configure the pin as an output and drive a
206 * value on the line. Use argument 1 to indicate high level, argument 0 to
207 * indicate low level. (Please see Documentation/driver-api/pinctl.rst,
208 * section "GPIO mode pitfalls" for a discussion around this parameter.)
209 * @PIN_CONFIG_POWER_SOURCE: if the pin can select between different power
210 * supplies, the argument to this parameter (on a custom format) tells
211 * the driver which alternative power source to use.
212 * @PIN_CONFIG_SLEEP_HARDWARE_STATE: indicate this is sleep related state.
213 * @PIN_CONFIG_SLEW_RATE: if the pin can select slew rate, the argument to
214 * this parameter (on a custom format) tells the driver which alternative
215 * slew rate to use.
216 * @PIN_CONFIG_SKEW_DELAY: if the pin has programmable skew rate (on inputs)
217 * or latch delay (on outputs) this parameter (in a custom format)
218 * specifies the clock skew or latch delay. It typically controls how
219 * many double inverters are put in front of the line.
220 * @PIN_CONFIG_END: this is the last enumerator for pin configurations, if
221 * you need to pass in custom configurations to the pin controller, use
222 * PIN_CONFIG_END+1 as the base offset.
223 * @PIN_CONFIG_MAX: this is the maximum configuration value that can be
224 * presented using the packed format.
225 */
226 enum pin_config_param {
227 PIN_CONFIG_BIAS_BUS_HOLD,
228 PIN_CONFIG_BIAS_DISABLE,
229 PIN_CONFIG_BIAS_HIGH_IMPEDANCE,
230 PIN_CONFIG_BIAS_PULL_DOWN,
231 PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
232 PIN_CONFIG_BIAS_PULL_UP,
233 PIN_CONFIG_DRIVE_OPEN_DRAIN,
234 PIN_CONFIG_DRIVE_OPEN_SOURCE,
235 PIN_CONFIG_DRIVE_PUSH_PULL,
236 PIN_CONFIG_DRIVE_STRENGTH,
237 PIN_CONFIG_INPUT_DEBOUNCE,
238 PIN_CONFIG_INPUT_ENABLE,
239 PIN_CONFIG_INPUT_SCHMITT,
240 PIN_CONFIG_INPUT_SCHMITT_ENABLE,
241 PIN_CONFIG_LOW_POWER_MODE,
242 PIN_CONFIG_OUTPUT_ENABLE,
243 PIN_CONFIG_OUTPUT,
244 PIN_CONFIG_POWER_SOURCE,
245 PIN_CONFIG_SLEEP_HARDWARE_STATE,
246 PIN_CONFIG_SLEW_RATE,
247 PIN_CONFIG_SKEW_DELAY,
248 PIN_CONFIG_END = 0x7F,
249 PIN_CONFIG_MAX = 0xFF,
250 };
251
252 #if CONFIG_IS_ENABLED(PINCTRL_GENERIC)
253 /**
254 * pinctrl_generic_set_state() - generic set_state operation
255 * Parse the DT node of @config and its children and handle generic properties
256 * such as "pins", "groups", "functions", and pin configuration parameters.
257 *
258 * @pctldev: pinctrl device
259 * @config: config device (pseudo device), pointing a config node in DTS
260 * @return: 0 on success, or negative error code on failure
261 */
262 int pinctrl_generic_set_state(struct udevice *pctldev, struct udevice *config);
263 #else
pinctrl_generic_set_state(struct udevice * pctldev,struct udevice * config)264 static inline int pinctrl_generic_set_state(struct udevice *pctldev,
265 struct udevice *config)
266 {
267 return -EINVAL;
268 }
269 #endif
270
271 #if CONFIG_IS_ENABLED(PINCTRL)
272 /**
273 * pinctrl_select_state() - set a device to a given state
274 *
275 * @dev: peripheral device
276 * @statename: state name, like "default"
277 * @return: 0 on success, or negative error code on failure
278 */
279 int pinctrl_select_state(struct udevice *dev, const char *statename);
280 #else
pinctrl_select_state(struct udevice * dev,const char * statename)281 static inline int pinctrl_select_state(struct udevice *dev,
282 const char *statename)
283 {
284 return -EINVAL;
285 }
286 #endif
287
288 /**
289 * pinctrl_request() - Request a particular pinctrl function
290 *
291 * @dev: Device to check (UCLASS_PINCTRL)
292 * @func: Function number (driver-specific)
293 * @flags: Flags (driver-specific)
294 * @return 0 if OK, -ve on error
295 */
296 int pinctrl_request(struct udevice *dev, int func, int flags);
297
298 /**
299 * pinctrl_request_noflags() - Request a particular pinctrl function
300 *
301 * This is similar to pinctrl_request() but uses 0 for @flags.
302 *
303 * @dev: Device to check (UCLASS_PINCTRL)
304 * @func: Function number (driver-specific)
305 * @return 0 if OK, -ve on error
306 */
307 int pinctrl_request_noflags(struct udevice *dev, int func);
308
309 /**
310 * pinctrl_get_periph_id() - get the peripheral ID for a device
311 *
312 * This generally looks at the peripheral's device tree node to work out the
313 * peripheral ID. The return value is normally interpreted as enum periph_id.
314 * so long as this is defined by the platform (which it should be).
315 *
316 * @dev: Pinctrl device to use for decoding
317 * @periph: Device to check
318 * @return peripheral ID of @periph, or -ENOENT on error
319 */
320 int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph);
321
322 /**
323 * pinctrl_decode_pin_config() - decode pin configuration flags
324 *
325 * This decodes some of the PIN_CONFIG values into flags, with each value
326 * being (1 << pin_cfg). This does not support things with values like the
327 * slew rate.
328 *
329 * @blob: Device tree blob
330 * @node: Node containing the PIN_CONFIG values
331 * @return decoded flag value, or -ve on error
332 */
333 int pinctrl_decode_pin_config(const void *blob, int node);
334
335 /**
336 * pinctrl_get_gpio_mux() - get the mux value for a particular GPIO
337 *
338 * This allows the raw mux value for a GPIO to be obtained. It is
339 * useful for displaying the function being used by that GPIO, such
340 * as with the 'gpio' command. This function is internal to the GPIO
341 * subsystem and should not be used by generic code. Typically it is
342 * used by a GPIO driver with knowledge of the SoC pinctrl setup.
343 *
344 * @dev: Pinctrl device to use
345 * @banknum: GPIO bank number
346 * @index: GPIO index within the bank
347 * @return mux value (SoC-specific, e.g. 0 for input, 1 for output)
348 */
349 int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index);
350
351 #endif /* __PINCTRL_H */
352