1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Copyright (C) 2015  Masahiro Yamada <yamada.masahiro@com>
4  */
5 
6 #ifndef __PINCTRL_H
7 #define __PINCTRL_H
8 
9 #define PINNAME_SIZE	10
10 #define PINMUX_SIZE	40
11 
12 /**
13  * struct pinconf_param - pin config parameters
14  * @property:		Property name in DT nodes
15  * @param:		ID for this config parameter
16  * @default_value:	default value for this config parameter used in case
17  *			no value is specified in DT nodes
18  */
19 struct pinconf_param {
20 	const char * const property;
21 	unsigned int param;
22 	u32 default_value;
23 };
24 
25 /**
26  * struct pinctrl_ops - pin control operations, to be implemented by
27  * pin controller drivers.
28  *
29  * set_state() is the only mandatory operation. You can implement your pinctrl
30  * driver with its own @set_state. In this case, the other callbacks are not
31  * required. Otherwise, generic pinctrl framework is also available; use
32  * pinctrl_generic_set_state for @set_state, and implement other operations
33  * depending on your necessity.
34  */
35 struct pinctrl_ops {
36 	/**
37 	 * @get_pins_count: Get the number of selectable pins
38 	 *
39 	 * @dev: Pinctrl device to use
40 	 *
41 	 * This function is necessary to parse the "pins" property in DTS.
42 	 *
43 	 * @Return:
44 	 *	number of selectable named pins available in this driver
45 	 */
46 	int (*get_pins_count)(struct udevice *dev);
47 
48 	/**
49 	 * @get_pin_name: Get the name of a pin
50 	 *
51 	 * @dev: Pinctrl device of the pin
52 	 *
53 	 * @selector: The pin selector
54 	 *
55 	 * This function is called by the core to figure out which pin it will
56 	 * do operations to. This function is necessary to parse the "pins"
57 	 * property in DTS.
58 	 *
59 	 * @Return: const pointer to the name of the pin
60 	 */
61 	const char *(*get_pin_name)(struct udevice *dev, unsigned selector);
62 
63 	/**
64 	 * @get_groups_count: Get the number of selectable groups
65 	 *
66 	 * @dev: Pinctrl device to use
67 	 *
68 	 * This function is necessary to parse the "groups" property in DTS.
69 	 *
70 	 * @Return:
71 	 *	number of selectable named groups available in the driver
72 	 */
73 	int (*get_groups_count)(struct udevice *dev);
74 
75 	/**
76 	 * @get_group_name: Get the name of a group
77 	 *
78 	 * @dev: Pinctrl device of the group
79 	 *
80 	 * @selector: The group selector
81 	 *
82 	 * This function is called by the core to figure out which group it
83 	 * will do operations to. This function is necessary to parse the
84 	 * "groups" property in DTS.
85 	 *
86 	 * @Return: Pointer to the name of the group
87 	 */
88 	const char *(*get_group_name)(struct udevice *dev, unsigned selector);
89 
90 	/**
91 	 * @get_functions_count: Get the number of selectable functions
92 	 *
93 	 * @dev: Pinctrl device to use
94 	 *
95 	 * This function is necessary for pin-muxing.
96 	 *
97 	 * @Return:
98 	 *	number of selectable named functions available in this driver
99 	 */
100 	int (*get_functions_count)(struct udevice *dev);
101 
102 	/**
103 	 * @get_function_name: Get the name of a function
104 	 *
105 	 * @dev: Pinmux device of the function
106 	 *
107 	 * @selector: The function selector
108 	 *
109 	 * This function is called by the core to figure out which mux setting
110 	 * it will map a certain device to. This function is necessary for
111 	 * pin-muxing.
112 	 *
113 	 * @Return:
114 	 *	Pointer to the function name of the muxing selector
115 	 */
116 	const char *(*get_function_name)(struct udevice *dev,
117 					 unsigned selector);
118 
119 	/**
120 	 * @pinmux_set: Mux a pin to a function
121 	 *
122 	 * @dev: Pinctrl device to use
123 	 *
124 	 * @pin_selector: The pin selector
125 	 *
126 	 * @func_selector: The func selector
127 	 *
128 	 * On simple controllers one of @pin_selector or @func_selector may be
129 	 * ignored. This function is necessary for pin-muxing against a single
130 	 * pin.
131 	 *
132 	 * @Return: 0 if OK, or negative error code on failure
133 	 */
134 	int (*pinmux_set)(struct udevice *dev, unsigned pin_selector,
135 			  unsigned func_selector);
136 
137 	/**
138 	 * @pinmux_group_set: Mux a group of pins to a function
139 	 *
140 	 * @dev: Pinctrl device to use
141 	 *
142 	 * @group_selector: The group selector
143 	 *
144 	 * @func_selector: The func selector
145 	 *
146 	 * On simple controllers one of @group_selector or @func_selector may be
147 	 * ignored. This function is necessary for pin-muxing against a group of
148 	 * pins.
149 	 *
150 	 * @Return: 0 if OK, or negative error code on failure
151 	 */
152 	int (*pinmux_group_set)(struct udevice *dev, unsigned group_selector,
153 				unsigned func_selector);
154 
155 	/**
156 	 * @pinmux_property_set: Enable a pinmux group
157 	 *
158 	 * @dev: Pinctrl device to use
159 	 *
160 	 * @pinmux_group: A u32 representing the pin identifier and mux
161 	 *                settings. The exact format of a pinmux group is left
162 	 *                up to the driver.
163 	 *
164 	 * Mux a single pin to a single function based on a driver-specific
165 	 * pinmux group. This function is necessary for parsing the "pinmux"
166 	 * property in DTS, and for pin-muxing against a pinmux group.
167 	 *
168 	 * @Return:
169 	 *	Pin selector for the muxed pin if OK, or negative error code on
170 	 *	failure
171 	 */
172 	int (*pinmux_property_set)(struct udevice *dev, u32 pinmux_group);
173 
174 	/**
175 	 * @pinconf_num_params:
176 	 *	Number of driver-specific parameters to be parsed from device
177 	 *	trees. This member is necessary for pin configuration.
178 	 */
179 	unsigned int pinconf_num_params;
180 
181 	/**
182 	 * @pinconf_params:
183 	 *	List of driver-specific parameters to be parsed from the device
184 	 *	tree. This member is necessary for pin configuration.
185 	 */
186 	const struct pinconf_param *pinconf_params;
187 
188 	/**
189 	 * @pinconf_set: Configure an individual pin with a parameter
190 	 *
191 	 * @dev: Pinctrl device to use
192 	 *
193 	 * @pin_selector: The pin selector
194 	 *
195 	 * @param: An &enum pin_config_param from @pinconf_params
196 	 *
197 	 * @argument: The argument to this param from the device tree, or
198 	 *            @pinconf_params.default_value
199 	 *
200 	 * This function is necessary for pin configuration against a single
201 	 * pin.
202 	 *
203 	 * @Return: 0 if OK, or negative error code on failure
204 	 */
205 	int (*pinconf_set)(struct udevice *dev, unsigned pin_selector,
206 			   unsigned param, unsigned argument);
207 
208 	/**
209 	 * @pinconf_group_set: Configure all pins in a group with a parameter
210 	 *
211 	 * @dev: Pinctrl device to use
212 	 *
213 	 * @pin_selector: The group selector
214 	 *
215 	 * @param: A &enum pin_config_param from
216 	 *         @pinconf_params
217 	 *
218 	 * @argument: The argument to this param from the device tree, or
219 	 *            @pinconf_params.default_value
220 	 *
221 	 * This function is necessary for pin configuration against a group of
222 	 * pins.
223 	 *
224 	 * @Return: 0 if OK, or negative error code on failure
225 	 */
226 	int (*pinconf_group_set)(struct udevice *dev, unsigned group_selector,
227 				 unsigned param, unsigned argument);
228 
229 	/**
230 	 * @set_state: Configure a pinctrl device
231 	 *
232 	 * @dev: Pinctrl device to use
233 	 *
234 	 * @config: Pseudo device pointing a config node
235 	 *
236 	 * This function is required to be implemented by all pinctrl drivers.
237 	 * Drivers may set this member to pinctrl_generic_set_state(), which
238 	 * will call other functions in &struct pinctrl_ops to parse
239 	 * @config.
240 	 *
241 	 * @Return: 0 if OK, or negative error code on failure
242 	 */
243 	int (*set_state)(struct udevice *dev, struct udevice *config);
244 
245 	/**
246 	 * @set_state_simple: Configure a pinctrl device
247 	 *
248 	 * @dev: Pinctrl device to use
249 	 *
250 	 * @config: Pseudo-device pointing a config node
251 	 *
252 	 * This function is usually a simpler version of set_state(). Only the
253 	 * first pinctrl device on the system is supported by this function.
254 	 *
255 	 * @Return: 0 if OK, or negative error code on failure
256 	 */
257 	int (*set_state_simple)(struct udevice *dev, struct udevice *periph);
258 
259 	/**
260 	 * @request: Request a particular pinctrl function
261 	 *
262 	 * @dev: Device to adjust (%UCLASS_PINCTRL)
263 	 *
264 	 * @func: Function number (driver-specific)
265 	 *
266 	 * This activates the selected function.
267 	 *
268 	 * @Return: 0 if OK, or negative error code on failure
269 	 */
270 	int (*request)(struct udevice *dev, int func, int flags);
271 
272 	/**
273 	* @get_periph_id: Get the peripheral ID for a device
274 	*
275 	* @dev: Pinctrl device to use for decoding
276 	*
277 	* @periph: Device to check
278 	*
279 	* This generally looks at the peripheral's device tree node to work
280 	* out the peripheral ID. The return value is normally interpreted as
281 	* &enum periph_id. so long as this is defined by the platform (which it
282 	* should be).
283 	*
284 	* @Return:
285 	*	Peripheral ID of @periph, or %-ENOENT on error
286 	*/
287 	int (*get_periph_id)(struct udevice *dev, struct udevice *periph);
288 
289 	/**
290 	 * @get_gpio_mux: Get the mux value for a particular GPIO
291 	 *
292 	 * @dev: Pinctrl device to use
293 	 *
294 	 * @banknum: GPIO bank number
295 	 *
296 	 * @index: GPIO index within the bank
297 	 *
298 	 * This allows the raw mux value for a GPIO to be obtained. It is
299 	 * useful for displaying the function being used by that GPIO, such
300 	 * as with the 'gpio' command. This function is internal to the GPIO
301 	 * subsystem and should not be used by generic code. Typically it is
302 	 * used by a GPIO driver with knowledge of the SoC pinctrl setup.
303 	 *
304 	 * @Return:
305 	 *	Mux value (SoC-specific, e.g. 0 for input, 1 for output)
306 	 */
307 	int (*get_gpio_mux)(struct udevice *dev, int banknum, int index);
308 
309 	/**
310 	 * @get_pin_muxing: Show pin muxing
311 	 *
312 	 * @dev: Pinctrl device to use
313 	 *
314 	 * @selector: Pin selector
315 	 *
316 	 * @buf: Buffer to fill with pin muxing description
317 	 *
318 	 * @size: Size of @buf
319 	 *
320 	 * This allows to display the muxing of a given pin. It's useful for
321 	 * debug purposes to know if a pin is configured as GPIO or as an
322 	 * alternate function and which one. Typically it is used by a PINCTRL
323 	 * driver with knowledge of the SoC pinctrl setup.
324 	 *
325 	 * @Return: 0 if OK, or negative error code on failure
326 	 */
327 	 int (*get_pin_muxing)(struct udevice *dev, unsigned int selector,
328 			       char *buf, int size);
329 
330 	/**
331 	 * @gpio_request_enable: Request and enable GPIO on a certain pin.
332 	 *
333 	 * @dev: Pinctrl device to use
334 	 *
335 	 * @selector: Pin selector
336 	 *
337 	 * Implement this only if you can mux every pin individually as GPIO.
338 	 * The affected GPIO range is passed along with an offset(pin number)
339 	 * into that specific GPIO range - function selectors and pin groups are
340 	 * orthogonal to this, the core will however make sure the pins do not
341 	 * collide.
342 	 *
343 	 * @Return:
344 	 *	0 if OK, or negative error code on failure
345 	 */
346 	int (*gpio_request_enable)(struct udevice *dev, unsigned int selector);
347 
348 	/**
349 	 * @gpio_disable_free: Free up GPIO muxing on a certain pin.
350 	 *
351 	 * @dev: Pinctrl device to use
352 	 *
353 	 * @selector: Pin selector
354 	 *
355 	 * This function is the reverse of @gpio_request_enable.
356 	 *
357 	 * @Return: 0 if OK, or negative error code on failure
358 	 */
359 	int (*gpio_disable_free)(struct udevice *dev, unsigned int selector);
360 };
361 
362 #define pinctrl_get_ops(dev)	((struct pinctrl_ops *)(dev)->driver->ops)
363 
364 /**
365  * enum pin_config_param - Generic pin configuration parameters
366  *
367  * @PIN_CONFIG_BIAS_BUS_HOLD: The pin will be set to weakly latch so that it
368  *	weakly drives the last value on a tristate bus, also known as a "bus
369  *	holder", "bus keeper" or "repeater". This allows another device on the
370  *	bus to change the value by driving the bus high or low and switching to
371  *	tristate. The argument is ignored.
372  * @PIN_CONFIG_BIAS_DISABLE: Disable any pin bias on the pin, a
373  *	transition from say pull-up to pull-down implies that you disable
374  *	pull-up in the process, this setting disables all biasing.
375  * @PIN_CONFIG_BIAS_HIGH_IMPEDANCE: The pin will be set to a high impedance
376  *	mode, also know as "third-state" (tristate) or "high-Z" or "floating".
377  *	On output pins this effectively disconnects the pin, which is useful
378  *	if for example some other pin is going to drive the signal connected
379  *	to it for a while. Pins used for input are usually always high
380  *	impedance.
381  * @PIN_CONFIG_BIAS_PULL_DOWN: The pin will be pulled down (usually with high
382  *	impedance to GROUND). If the argument is != 0 pull-down is enabled,
383  *	if it is 0, pull-down is total, i.e. the pin is connected to GROUND.
384  * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: The pin will be pulled up or down based
385  *	on embedded knowledge of the controller hardware, like current mux
386  *	function. The pull direction and possibly strength too will normally
387  *	be decided completely inside the hardware block and not be readable
388  *	from the kernel side.
389  *	If the argument is != 0 pull up/down is enabled, if it is 0, the
390  *	configuration is ignored. The proper way to disable it is to use
391  *	@PIN_CONFIG_BIAS_DISABLE.
392  * @PIN_CONFIG_BIAS_PULL_UP: The pin will be pulled up (usually with high
393  *	impedance to VDD). If the argument is != 0 pull-up is enabled,
394  *	if it is 0, pull-up is total, i.e. the pin is connected to VDD.
395  * @PIN_CONFIG_DRIVE_OPEN_DRAIN: The pin will be driven with open drain (open
396  *	collector) which means it is usually wired with other output ports
397  *	which are then pulled up with an external resistor. Setting this
398  *	config will enable open drain mode, the argument is ignored.
399  * @PIN_CONFIG_DRIVE_OPEN_SOURCE: The pin will be driven with open source
400  *	(open emitter). Setting this config will enable open source mode, the
401  *	argument is ignored.
402  * @PIN_CONFIG_DRIVE_PUSH_PULL: The pin will be driven actively high and
403  *	low, this is the most typical case and is typically achieved with two
404  *	active transistors on the output. Setting this config will enable
405  *	push-pull mode, the argument is ignored.
406  * @PIN_CONFIG_DRIVE_STRENGTH: The pin will sink or source at most the current
407  *	passed as argument. The argument is in mA.
408  * @PIN_CONFIG_DRIVE_STRENGTH_UA: The pin will sink or source at most the
409  *	current passed as argument. The argument is in uA.
410  * @PIN_CONFIG_INPUT_DEBOUNCE: This will configure the pin to debounce mode,
411  *	which means it will wait for signals to settle when reading inputs. The
412  *	argument gives the debounce time in usecs. Setting the
413  *	argument to zero turns debouncing off.
414  * @PIN_CONFIG_INPUT_ENABLE: Enable the pin's input.  Note that this does not
415  *	affect the pin's ability to drive output.  1 enables input, 0 disables
416  *	input.
417  * @PIN_CONFIG_INPUT_SCHMITT: This will configure an input pin to run in
418  *	schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis,
419  *	the threshold value is given on a custom format as argument when
420  *	setting pins to this mode.
421  * @PIN_CONFIG_INPUT_SCHMITT_ENABLE: Control schmitt-trigger mode on the pin.
422  *      If the argument != 0, schmitt-trigger mode is enabled. If it's 0,
423  *      schmitt-trigger mode is disabled.
424  * @PIN_CONFIG_LOW_POWER_MODE: This will configure the pin for low power
425  *	operation, if several modes of operation are supported these can be
426  *	passed in the argument on a custom form, else just use argument 1
427  *	to indicate low power mode, argument 0 turns low power mode off.
428  * @PIN_CONFIG_OUTPUT_ENABLE: This will enable the pin's output mode
429  *	without driving a value there. For most platforms this reduces to
430  *	enable the output buffers and then let the pin controller current
431  *	configuration (eg. the currently selected mux function) drive values on
432  *	the line. Use argument 1 to enable output mode, argument 0 to disable
433  *	it.
434  * @PIN_CONFIG_OUTPUT: This will configure the pin as an output and drive a
435  *	value on the line. Use argument 1 to indicate high level, argument 0 to
436  *	indicate low level. (Please see Documentation/driver-api/pinctl.rst,
437  *	section "GPIO mode pitfalls" for a discussion around this parameter.)
438  * @PIN_CONFIG_POWER_SOURCE: If the pin can select between different power
439  *	supplies, the argument to this parameter (on a custom format) tells
440  *	the driver which alternative power source to use.
441  * @PIN_CONFIG_SLEEP_HARDWARE_STATE: Indicate this is sleep related state.
442  * @PIN_CONFIG_SLEW_RATE: If the pin can select slew rate, the argument to
443  *	this parameter (on a custom format) tells the driver which alternative
444  *	slew rate to use.
445  * @PIN_CONFIG_SKEW_DELAY: If the pin has programmable skew rate (on inputs)
446  *	or latch delay (on outputs) this parameter (in a custom format)
447  *	specifies the clock skew or latch delay. It typically controls how
448  *	many double inverters are put in front of the line.
449  * @PIN_CONFIG_END: This is the last enumerator for pin configurations, if
450  *	you need to pass in custom configurations to the pin controller, use
451  *	PIN_CONFIG_END+1 as the base offset.
452  * @PIN_CONFIG_MAX: This is the maximum configuration value that can be
453  *	presented using the packed format.
454  */
455 enum pin_config_param {
456 	PIN_CONFIG_BIAS_BUS_HOLD,
457 	PIN_CONFIG_BIAS_DISABLE,
458 	PIN_CONFIG_BIAS_HIGH_IMPEDANCE,
459 	PIN_CONFIG_BIAS_PULL_DOWN,
460 	PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
461 	PIN_CONFIG_BIAS_PULL_UP,
462 	PIN_CONFIG_DRIVE_OPEN_DRAIN,
463 	PIN_CONFIG_DRIVE_OPEN_SOURCE,
464 	PIN_CONFIG_DRIVE_PUSH_PULL,
465 	PIN_CONFIG_DRIVE_STRENGTH,
466 	PIN_CONFIG_DRIVE_STRENGTH_UA,
467 	PIN_CONFIG_INPUT_DEBOUNCE,
468 	PIN_CONFIG_INPUT_ENABLE,
469 	PIN_CONFIG_INPUT_SCHMITT,
470 	PIN_CONFIG_INPUT_SCHMITT_ENABLE,
471 	PIN_CONFIG_LOW_POWER_MODE,
472 	PIN_CONFIG_OUTPUT_ENABLE,
473 	PIN_CONFIG_OUTPUT,
474 	PIN_CONFIG_POWER_SOURCE,
475 	PIN_CONFIG_SLEEP_HARDWARE_STATE,
476 	PIN_CONFIG_SLEW_RATE,
477 	PIN_CONFIG_SKEW_DELAY,
478 	PIN_CONFIG_END = 0x7F,
479 	PIN_CONFIG_MAX = 0xFF,
480 };
481 
482 #if CONFIG_IS_ENABLED(PINCTRL_GENERIC)
483 /**
484  * pinctrl_generic_set_state() - Generic set_state operation
485  * @pctldev:	Pinctrl device to use
486  * @config:	Config device (pseudo device), pointing a config node in DTS
487  *
488  * Parse the DT node of @config and its children and handle generic properties
489  * such as "pins", "groups", "functions", and pin configuration parameters.
490  *
491  * Return: 0 on success, or negative error code on failure
492  */
493 int pinctrl_generic_set_state(struct udevice *pctldev, struct udevice *config);
494 #else
pinctrl_generic_set_state(struct udevice * pctldev,struct udevice * config)495 static inline int pinctrl_generic_set_state(struct udevice *pctldev,
496 					    struct udevice *config)
497 {
498 	return -EINVAL;
499 }
500 #endif
501 
502 #if CONFIG_IS_ENABLED(PINCTRL)
503 /**
504  * pinctrl_select_state() - Set a device to a given state
505  * @dev:	Peripheral device
506  * @statename:	State name, like "default"
507  *
508  * Return: 0 on success, or negative error code on failure
509  */
510 int pinctrl_select_state(struct udevice *dev, const char *statename);
511 #else
pinctrl_select_state(struct udevice * dev,const char * statename)512 static inline int pinctrl_select_state(struct udevice *dev,
513 				       const char *statename)
514 {
515 	return -EINVAL;
516 }
517 #endif
518 
519 /**
520  * pinctrl_request() - Request a particular pinctrl function
521  * @dev:	Pinctrl device to use
522  * @func:	Function number (driver-specific)
523  * @flags:	Flags (driver-specific)
524  *
525  * Return: 0 if OK, or negative error code on failure
526  */
527 int pinctrl_request(struct udevice *dev, int func, int flags);
528 
529 /**
530  * pinctrl_request_noflags() - Request a particular pinctrl function
531  * @dev:	Pinctrl device to use
532  * @func:	Function number (driver-specific)
533  *
534  * This is similar to pinctrl_request() but uses 0 for @flags.
535  *
536  * Return: 0 if OK, or negative error code on failure
537  */
538 int pinctrl_request_noflags(struct udevice *dev, int func);
539 
540 /**
541  * pinctrl_get_periph_id() - Get the peripheral ID for a device
542  * @dev:	Pinctrl device to use for decoding
543  * @periph:	Device to check
544  *
545  * This generally looks at the peripheral's device tree node to work out the
546  * peripheral ID. The return value is normally interpreted as enum periph_id.
547  * so long as this is defined by the platform (which it should be).
548  *
549  * Return: Peripheral ID of @periph, or -ENOENT on error
550  */
551 int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph);
552 
553 /**
554  * pinctrl_get_gpio_mux() - get the mux value for a particular GPIO
555  * @dev:	Pinctrl device to use
556  * @banknum:	GPIO bank number
557  * @index:	GPIO index within the bank
558  *
559  * This allows the raw mux value for a GPIO to be obtained. It is
560  * useful for displaying the function being used by that GPIO, such
561  * as with the 'gpio' command. This function is internal to the GPIO
562  * subsystem and should not be used by generic code. Typically it is
563  * used by a GPIO driver with knowledge of the SoC pinctrl setup.
564  *
565  * Return: Mux value (SoC-specific, e.g. 0 for input, 1 for output)
566 */
567 int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index);
568 
569 /**
570  * pinctrl_get_pin_muxing() - Returns the muxing description
571  * @dev:	Pinctrl device to use
572  * @selector:	Pin index within pin-controller
573  * @buf:	Pin's muxing description
574  * @size:	Pin's muxing description length
575  *
576  * This allows to display the muxing description of the given pin for
577  * debug purpose
578  *
579  * Return: 0 if OK, or negative error code on failure
580  */
581 int pinctrl_get_pin_muxing(struct udevice *dev, int selector, char *buf,
582 			   int size);
583 
584 /**
585  * pinctrl_get_pins_count() - Display pin-controller pins number
586  * @dev:	Pinctrl device to use
587  *
588  * This allows to know the number of pins owned by a given pin-controller
589  *
590  * Return: Number of pins if OK, or negative error code on failure
591  */
592 int pinctrl_get_pins_count(struct udevice *dev);
593 
594 /**
595  * pinctrl_get_pin_name() - Returns the pin's name
596  * @dev:	Pinctrl device to use
597  * @selector:	Pin index within pin-controller
598  * @buf:	Buffer to fill with the name of the pin
599  * @size:	Size of @buf
600  *
601  * This allows to display the pin's name for debug purpose
602  *
603  * Return: 0 if OK, or negative error code on failure
604  */
605 int pinctrl_get_pin_name(struct udevice *dev, int selector, char *buf,
606 			 int size);
607 
608 /**
609  * pinctrl_gpio_request() - Request a single pin to be used as GPIO
610  * @dev:	GPIO peripheral device
611  * @offset:	GPIO pin offset from the GPIO controller
612  *
613  * Return: 0 on success, or negative error code on failure
614  */
615 int pinctrl_gpio_request(struct udevice *dev, unsigned offset);
616 
617 /**
618  * pinctrl_gpio_free() - Free a single pin used as GPIO
619  * @dev:	GPIO peripheral device
620  * @offset:	GPIO pin offset from the GPIO controller
621  *
622  * Return: 0 on success, or negative error code on failure
623  */
624 int pinctrl_gpio_free(struct udevice *dev, unsigned offset);
625 
626 #endif /* __PINCTRL_H */
627