xref: /openbmc/u-boot/include/dm/pinctrl.h (revision dd1033e4)
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 #define PINNAME_SIZE	10
10 #define PINMUX_SIZE	40
11 
12 /**
13  * struct pinconf_param - pin config parameters
14  *
15  * @property: property name in DT nodes
16  * @param: ID for this config parameter
17  * @default_value: default value for this config parameter used in case
18  *	no value is specified in DT nodes
19  */
20 struct pinconf_param {
21 	const char * const property;
22 	unsigned int param;
23 	u32 default_value;
24 };
25 
26 /**
27  * struct pinctrl_ops - pin control operations, to be implemented by
28  * pin controller drivers.
29  *
30  * The @set_state is the only mandatory operation.  You can implement your
31  * pinctrl driver with its own @set_state.  In this case, the other callbacks
32  * are not required.  Otherwise, generic pinctrl framework is also available;
33  * use pinctrl_generic_set_state for @set_state, and implement other operations
34  * depending on your necessity.
35  *
36  * @get_pins_count: return number of selectable named pins available
37  *	in this driver.  (necessary to parse "pins" property in DTS)
38  * @get_pin_name: return the pin name of the pin selector,
39  *	called by the core to figure out which pin it shall do
40  *	operations to.  (necessary to parse "pins" property in DTS)
41  * @get_groups_count: return number of selectable named groups available
42  *	in this driver.  (necessary to parse "groups" property in DTS)
43  * @get_group_name: return the group name of the group selector,
44  *	called by the core to figure out which pin group it shall do
45  *	operations to.  (necessary to parse "groups" property in DTS)
46  * @get_functions_count: return number of selectable named functions available
47  *	in this driver.  (necessary for pin-muxing)
48  * @get_function_name: return the function name of the muxing selector,
49  *	called by the core to figure out which mux setting it shall map a
50  *	certain device to.  (necessary for pin-muxing)
51  * @pinmux_set: enable a certain muxing function with a certain pin.
52  *	The @func_selector selects a certain function whereas @pin_selector
53  *	selects a certain pin to be used. On simple controllers one of them
54  *	may be ignored.  (necessary for pin-muxing against a single pin)
55  * @pinmux_group_set: enable a certain muxing function with a certain pin
56  *	group.  The @func_selector selects a certain function whereas
57  *	@group_selector selects a certain set of pins to be used. On simple
58  *	controllers one of them may be ignored.
59  *	(necessary for pin-muxing against a pin group)
60  * @pinconf_num_params: number of driver-specific parameters to be parsed
61  *	from device trees  (necessary for pin-configuration)
62  * @pinconf_params: list of driver_specific parameters to be parsed from
63  *	device trees  (necessary for pin-configuration)
64  * @pinconf_set: configure an individual pin with a given parameter.
65  *	(necessary for pin-configuration against a single pin)
66  * @pinconf_group_set: configure all pins in a group with a given parameter.
67  *	(necessary for pin-configuration against a pin group)
68  * @set_state: do pinctrl operations specified by @config, a pseudo device
69  *	pointing a config node. (necessary for pinctrl_full)
70  * @set_state_simple: do needed pinctrl operations for a peripherl @periph.
71  *	(necessary for pinctrl_simple)
72  * @get_pin_muxing: display the muxing of a given pin.
73  */
74 struct pinctrl_ops {
75 	int (*get_pins_count)(struct udevice *dev);
76 	const char *(*get_pin_name)(struct udevice *dev, unsigned selector);
77 	int (*get_groups_count)(struct udevice *dev);
78 	const char *(*get_group_name)(struct udevice *dev, unsigned selector);
79 	int (*get_functions_count)(struct udevice *dev);
80 	const char *(*get_function_name)(struct udevice *dev,
81 					 unsigned selector);
82 	int (*pinmux_set)(struct udevice *dev, unsigned pin_selector,
83 			  unsigned func_selector);
84 	int (*pinmux_group_set)(struct udevice *dev, unsigned group_selector,
85 				unsigned func_selector);
86 	unsigned int pinconf_num_params;
87 	const struct pinconf_param *pinconf_params;
88 	int (*pinconf_set)(struct udevice *dev, unsigned pin_selector,
89 			   unsigned param, unsigned argument);
90 	int (*pinconf_group_set)(struct udevice *dev, unsigned group_selector,
91 				 unsigned param, unsigned argument);
92 	int (*set_state)(struct udevice *dev, struct udevice *config);
93 
94 	/* for pinctrl-simple */
95 	int (*set_state_simple)(struct udevice *dev, struct udevice *periph);
96 	/**
97 	 * request() - Request a particular pinctrl function
98 	 *
99 	 * This activates the selected function.
100 	 *
101 	 * @dev:	Device to adjust (UCLASS_PINCTRL)
102 	 * @func:	Function number (driver-specific)
103 	 * @return 0 if OK, -ve on error
104 	 */
105 	int (*request)(struct udevice *dev, int func, int flags);
106 
107 	/**
108 	* get_periph_id() - get the peripheral ID for a device
109 	*
110 	* This generally looks at the peripheral's device tree node to work
111 	* out the peripheral ID. The return value is normally interpreted as
112 	* enum periph_id. so long as this is defined by the platform (which it
113 	* should be).
114 	*
115 	* @dev:		Pinctrl device to use for decoding
116 	* @periph:	Device to check
117 	* @return peripheral ID of @periph, or -ENOENT on error
118 	*/
119 	int (*get_periph_id)(struct udevice *dev, struct udevice *periph);
120 
121 	/**
122 	 * get_gpio_mux() - get the mux value for a particular GPIO
123 	 *
124 	 * This allows the raw mux value for a GPIO to be obtained. It is
125 	 * useful for displaying the function being used by that GPIO, such
126 	 * as with the 'gpio' command. This function is internal to the GPIO
127 	 * subsystem and should not be used by generic code. Typically it is
128 	 * used by a GPIO driver with knowledge of the SoC pinctrl setup.
129 	 *
130 	* @dev:		Pinctrl device to use
131 	* @banknum:	GPIO bank number
132 	* @index:	GPIO index within the bank
133 	* @return mux value (SoC-specific, e.g. 0 for input, 1 for output)
134 	 */
135 	int (*get_gpio_mux)(struct udevice *dev, int banknum, int index);
136 
137 	/**
138 	 * get_pin_muxing() - show pin muxing
139 	 *
140 	 * This allows to display the muxing of a given pin. It's useful for
141 	 * debug purpose to know if a pin is configured as GPIO or as an
142 	 * alternate function and which one.
143 	 * Typically it is used by a PINCTRL driver with knowledge of the SoC
144 	 * pinctrl setup.
145 	 *
146 	 * @dev:	Pinctrl device to use
147 	 * @selector:	Pin selector
148 	 * @buf		Pin's muxing description
149 	 * @size	Pin's muxing description length
150 	 * return 0 if OK, -ve on error
151 	 */
152 	 int (*get_pin_muxing)(struct udevice *dev, unsigned int selector,
153 			       char *buf, int size);
154 };
155 
156 #define pinctrl_get_ops(dev)	((struct pinctrl_ops *)(dev)->driver->ops)
157 
158 /**
159  * Generic pin configuration paramters
160  *
161  * enum pin_config_param - possible pin configuration parameters
162  * @PIN_CONFIG_BIAS_BUS_HOLD: the pin will be set to weakly latch so that it
163  *	weakly drives the last value on a tristate bus, also known as a "bus
164  *	holder", "bus keeper" or "repeater". This allows another device on the
165  *	bus to change the value by driving the bus high or low and switching to
166  *	tristate. The argument is ignored.
167  * @PIN_CONFIG_BIAS_DISABLE: disable any pin bias on the pin, a
168  *	transition from say pull-up to pull-down implies that you disable
169  *	pull-up in the process, this setting disables all biasing.
170  * @PIN_CONFIG_BIAS_HIGH_IMPEDANCE: the pin will be set to a high impedance
171  *	mode, also know as "third-state" (tristate) or "high-Z" or "floating".
172  *	On output pins this effectively disconnects the pin, which is useful
173  *	if for example some other pin is going to drive the signal connected
174  *	to it for a while. Pins used for input are usually always high
175  *	impedance.
176  * @PIN_CONFIG_BIAS_PULL_DOWN: the pin will be pulled down (usually with high
177  *	impedance to GROUND). If the argument is != 0 pull-down is enabled,
178  *	if it is 0, pull-down is total, i.e. the pin is connected to GROUND.
179  * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down based
180  *	on embedded knowledge of the controller hardware, like current mux
181  *	function. The pull direction and possibly strength too will normally
182  *	be decided completely inside the hardware block and not be readable
183  *	from the kernel side.
184  *	If the argument is != 0 pull up/down is enabled, if it is 0, the
185  *	configuration is ignored. The proper way to disable it is to use
186  *	@PIN_CONFIG_BIAS_DISABLE.
187  * @PIN_CONFIG_BIAS_PULL_UP: the pin will be pulled up (usually with high
188  *	impedance to VDD). If the argument is != 0 pull-up is enabled,
189  *	if it is 0, pull-up is total, i.e. the pin is connected to VDD.
190  * @PIN_CONFIG_DRIVE_OPEN_DRAIN: the pin will be driven with open drain (open
191  *	collector) which means it is usually wired with other output ports
192  *	which are then pulled up with an external resistor. Setting this
193  *	config will enable open drain mode, the argument is ignored.
194  * @PIN_CONFIG_DRIVE_OPEN_SOURCE: the pin will be driven with open source
195  *	(open emitter). Setting this config will enable open source mode, the
196  *	argument is ignored.
197  * @PIN_CONFIG_DRIVE_PUSH_PULL: the pin will be driven actively high and
198  *	low, this is the most typical case and is typically achieved with two
199  *	active transistors on the output. Setting this config will enable
200  *	push-pull mode, the argument is ignored.
201  * @PIN_CONFIG_DRIVE_STRENGTH: the pin will sink or source at most the current
202  *	passed as argument. The argument is in mA.
203  * @PIN_CONFIG_INPUT_DEBOUNCE: this will configure the pin to debounce mode,
204  *	which means it will wait for signals to settle when reading inputs. The
205  *	argument gives the debounce time in usecs. Setting the
206  *	argument to zero turns debouncing off.
207  * @PIN_CONFIG_INPUT_ENABLE: enable the pin's input.  Note that this does not
208  *	affect the pin's ability to drive output.  1 enables input, 0 disables
209  *	input.
210  * @PIN_CONFIG_INPUT_SCHMITT: this will configure an input pin to run in
211  *	schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis,
212  *	the threshold value is given on a custom format as argument when
213  *	setting pins to this mode.
214  * @PIN_CONFIG_INPUT_SCHMITT_ENABLE: control schmitt-trigger mode on the pin.
215  *      If the argument != 0, schmitt-trigger mode is enabled. If it's 0,
216  *      schmitt-trigger mode is disabled.
217  * @PIN_CONFIG_LOW_POWER_MODE: this will configure the pin for low power
218  *	operation, if several modes of operation are supported these can be
219  *	passed in the argument on a custom form, else just use argument 1
220  *	to indicate low power mode, argument 0 turns low power mode off.
221  * @PIN_CONFIG_OUTPUT_ENABLE: this will enable the pin's output mode
222  *	without driving a value there. For most platforms this reduces to
223  *	enable the output buffers and then let the pin controller current
224  *	configuration (eg. the currently selected mux function) drive values on
225  *	the line. Use argument 1 to enable output mode, argument 0 to disable
226  *	it.
227  * @PIN_CONFIG_OUTPUT: this will configure the pin as an output and drive a
228  *	value on the line. Use argument 1 to indicate high level, argument 0 to
229  *	indicate low level. (Please see Documentation/driver-api/pinctl.rst,
230  *	section "GPIO mode pitfalls" for a discussion around this parameter.)
231  * @PIN_CONFIG_POWER_SOURCE: if the pin can select between different power
232  *	supplies, the argument to this parameter (on a custom format) tells
233  *	the driver which alternative power source to use.
234  * @PIN_CONFIG_SLEEP_HARDWARE_STATE: indicate this is sleep related state.
235  * @PIN_CONFIG_SLEW_RATE: if the pin can select slew rate, the argument to
236  *	this parameter (on a custom format) tells the driver which alternative
237  *	slew rate to use.
238  * @PIN_CONFIG_SKEW_DELAY: if the pin has programmable skew rate (on inputs)
239  *	or latch delay (on outputs) this parameter (in a custom format)
240  *	specifies the clock skew or latch delay. It typically controls how
241  *	many double inverters are put in front of the line.
242  * @PIN_CONFIG_END: this is the last enumerator for pin configurations, if
243  *	you need to pass in custom configurations to the pin controller, use
244  *	PIN_CONFIG_END+1 as the base offset.
245  * @PIN_CONFIG_MAX: this is the maximum configuration value that can be
246  *	presented using the packed format.
247  */
248 enum pin_config_param {
249 	PIN_CONFIG_BIAS_BUS_HOLD,
250 	PIN_CONFIG_BIAS_DISABLE,
251 	PIN_CONFIG_BIAS_HIGH_IMPEDANCE,
252 	PIN_CONFIG_BIAS_PULL_DOWN,
253 	PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
254 	PIN_CONFIG_BIAS_PULL_UP,
255 	PIN_CONFIG_DRIVE_OPEN_DRAIN,
256 	PIN_CONFIG_DRIVE_OPEN_SOURCE,
257 	PIN_CONFIG_DRIVE_PUSH_PULL,
258 	PIN_CONFIG_DRIVE_STRENGTH,
259 	PIN_CONFIG_INPUT_DEBOUNCE,
260 	PIN_CONFIG_INPUT_ENABLE,
261 	PIN_CONFIG_INPUT_SCHMITT,
262 	PIN_CONFIG_INPUT_SCHMITT_ENABLE,
263 	PIN_CONFIG_LOW_POWER_MODE,
264 	PIN_CONFIG_OUTPUT_ENABLE,
265 	PIN_CONFIG_OUTPUT,
266 	PIN_CONFIG_POWER_SOURCE,
267 	PIN_CONFIG_SLEEP_HARDWARE_STATE,
268 	PIN_CONFIG_SLEW_RATE,
269 	PIN_CONFIG_SKEW_DELAY,
270 	PIN_CONFIG_END = 0x7F,
271 	PIN_CONFIG_MAX = 0xFF,
272 };
273 
274 #if CONFIG_IS_ENABLED(PINCTRL_GENERIC)
275 /**
276  * pinctrl_generic_set_state() - generic set_state operation
277  * Parse the DT node of @config and its children and handle generic properties
278  * such as "pins", "groups", "functions", and pin configuration parameters.
279  *
280  * @pctldev: pinctrl device
281  * @config: config device (pseudo device), pointing a config node in DTS
282  * @return: 0 on success, or negative error code on failure
283  */
284 int pinctrl_generic_set_state(struct udevice *pctldev, struct udevice *config);
285 #else
286 static inline int pinctrl_generic_set_state(struct udevice *pctldev,
287 					    struct udevice *config)
288 {
289 	return -EINVAL;
290 }
291 #endif
292 
293 #if CONFIG_IS_ENABLED(PINCTRL)
294 /**
295  * pinctrl_select_state() - set a device to a given state
296  *
297  * @dev: peripheral device
298  * @statename: state name, like "default"
299  * @return: 0 on success, or negative error code on failure
300  */
301 int pinctrl_select_state(struct udevice *dev, const char *statename);
302 #else
303 static inline int pinctrl_select_state(struct udevice *dev,
304 				       const char *statename)
305 {
306 	return -EINVAL;
307 }
308 #endif
309 
310 /**
311  * pinctrl_request() - Request a particular pinctrl function
312  *
313  * @dev:	Device to check (UCLASS_PINCTRL)
314  * @func:	Function number (driver-specific)
315  * @flags:	Flags (driver-specific)
316  * @return 0 if OK, -ve on error
317  */
318 int pinctrl_request(struct udevice *dev, int func, int flags);
319 
320 /**
321  * pinctrl_request_noflags() - Request a particular pinctrl function
322  *
323  * This is similar to pinctrl_request() but uses 0 for @flags.
324  *
325  * @dev:	Device to check (UCLASS_PINCTRL)
326  * @func:	Function number (driver-specific)
327  * @return 0 if OK, -ve on error
328  */
329 int pinctrl_request_noflags(struct udevice *dev, int func);
330 
331 /**
332  * pinctrl_get_periph_id() - get the peripheral ID for a device
333  *
334  * This generally looks at the peripheral's device tree node to work out the
335  * peripheral ID. The return value is normally interpreted as enum periph_id.
336  * so long as this is defined by the platform (which it should be).
337  *
338  * @dev:	Pinctrl device to use for decoding
339  * @periph:	Device to check
340  * @return peripheral ID of @periph, or -ENOENT on error
341  */
342 int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph);
343 
344 /**
345  * pinctrl_decode_pin_config() - decode pin configuration flags
346  *
347  * This decodes some of the PIN_CONFIG values into flags, with each value
348  * being (1 << pin_cfg). This does not support things with values like the
349  * slew rate.
350  *
351  * @blob:	Device tree blob
352  * @node:	Node containing the PIN_CONFIG values
353  * @return decoded flag value, or -ve on error
354  */
355 int pinctrl_decode_pin_config(const void *blob, int node);
356 
357 /**
358  * pinctrl_get_gpio_mux() - get the mux value for a particular GPIO
359  *
360  * This allows the raw mux value for a GPIO to be obtained. It is
361  * useful for displaying the function being used by that GPIO, such
362  * as with the 'gpio' command. This function is internal to the GPIO
363  * subsystem and should not be used by generic code. Typically it is
364  * used by a GPIO driver with knowledge of the SoC pinctrl setup.
365  *
366  * @dev:	Pinctrl device to use
367  * @banknum:	GPIO bank number
368  * @index:	GPIO index within the bank
369  * @return mux value (SoC-specific, e.g. 0 for input, 1 for output)
370 */
371 int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index);
372 
373 /**
374  * pinctrl_get_pin_muxing() - Returns the muxing description
375  *
376  * This allows to display the muxing description of the given pin for
377  * debug purpose
378  *
379  * @dev:	Pinctrl device to use
380  * @selector	Pin index within pin-controller
381  * @buf		Pin's muxing description
382  * @size	Pin's muxing description length
383  * @return 0 if OK, -ve on error
384  */
385 int pinctrl_get_pin_muxing(struct udevice *dev, int selector, char *buf,
386 			   int size);
387 
388 /**
389  * pinctrl_get_pins_count() - display pin-controller pins number
390  *
391  * This allows to know the number of pins owned by a given pin-controller
392  *
393  * @dev:	Pinctrl device to use
394  * @return pins number if OK, -ve on error
395  */
396 int pinctrl_get_pins_count(struct udevice *dev);
397 
398 /**
399  * pinctrl_get_pin_name() - Returns the pin's name
400  *
401  * This allows to display the pin's name for debug purpose
402  *
403  * @dev:	Pinctrl device to use
404  * @selector	Pin index within pin-controller
405  * @buf		Pin's name
406  * @return 0 if OK, -ve on error
407  */
408 int pinctrl_get_pin_name(struct udevice *dev, int selector, char *buf,
409 			 int size);
410 #endif /* __PINCTRL_H */
411