xref: /openbmc/u-boot/include/dm/pinctrl.h (revision 0093b3fc)
1 /*
2  * Copyright (C) 2015  Masahiro Yamada <yamada.masahiro@socionext.com>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #ifndef __PINCTRL_H
8 #define __PINCTRL_H
9 
10 /**
11  * struct pinconf_param - pin config parameters
12  *
13  * @property: property name in DT nodes
14  * @param: ID for this config parameter
15  * @default_value: default value for this config parameter used in case
16  *	no value is specified in DT nodes
17  */
18 struct pinconf_param {
19 	const char * const property;
20 	unsigned int param;
21 	u32 default_value;
22 };
23 
24 /**
25  * struct pinctrl_ops - pin control operations, to be implemented by
26  * pin controller drivers.
27  *
28  * The @set_state is the only mandatory operation.  You can implement your
29  * pinctrl driver with its own @set_state.  In this case, the other callbacks
30  * are not required.  Otherwise, generic pinctrl framework is also available;
31  * use pinctrl_generic_set_state for @set_state, and implement other operations
32  * depending on your necessity.
33  *
34  * @get_pins_count: return number of selectable named pins available
35  *	in this driver.  (necessary to parse "pins" property in DTS)
36  * @get_pin_name: return the pin name of the pin selector,
37  *	called by the core to figure out which pin it shall do
38  *	operations to.  (necessary to parse "pins" property in DTS)
39  * @get_groups_count: return number of selectable named groups available
40  *	in this driver.  (necessary to parse "groups" property in DTS)
41  * @get_group_name: return the group name of the group selector,
42  *	called by the core to figure out which pin group it shall do
43  *	operations to.  (necessary to parse "groups" property in DTS)
44  * @get_functions_count: return number of selectable named functions available
45  *	in this driver.  (necessary for pin-muxing)
46  * @get_function_name: return the function name of the muxing selector,
47  *	called by the core to figure out which mux setting it shall map a
48  *	certain device to.  (necessary for pin-muxing)
49  * @pinmux_set: enable a certain muxing function with a certain pin.
50  *	The @func_selector selects a certain function whereas @pin_selector
51  *	selects a certain pin to be used. On simple controllers one of them
52  *	may be ignored.  (necessary for pin-muxing against a single pin)
53  * @pinmux_group_set: enable a certain muxing function with a certain pin
54  *	group.  The @func_selector selects a certain function whereas
55  *	@group_selector selects a certain set of pins to be used. On simple
56  *	controllers one of them may be ignored.
57  *	(necessary for pin-muxing against a pin group)
58  * @pinconf_num_params: number of driver-specific parameters to be parsed
59  *	from device trees  (necessary for pin-configuration)
60  * @pinconf_params: list of driver_specific parameters to be parsed from
61  *	device trees  (necessary for pin-configuration)
62  * @pinconf_set: configure an individual pin with a given parameter.
63  *	(necessary for pin-configuration against a single pin)
64  * @pinconf_group_set: configure all pins in a group with a given parameter.
65  *	(necessary for pin-configuration against a pin group)
66  * @set_state: do pinctrl operations specified by @config, a pseudo device
67  *	pointing a config node. (necessary for pinctrl_full)
68  * @set_state_simple: do needed pinctrl operations for a peripherl @periph.
69  *	(necessary for pinctrl_simple)
70  */
71 struct pinctrl_ops {
72 	int (*get_pins_count)(struct udevice *dev);
73 	const char *(*get_pin_name)(struct udevice *dev, unsigned selector);
74 	int (*get_groups_count)(struct udevice *dev);
75 	const char *(*get_group_name)(struct udevice *dev, unsigned selector);
76 	int (*get_functions_count)(struct udevice *dev);
77 	const char *(*get_function_name)(struct udevice *dev,
78 					 unsigned selector);
79 	int (*pinmux_set)(struct udevice *dev, unsigned pin_selector,
80 			  unsigned func_selector);
81 	int (*pinmux_group_set)(struct udevice *dev, unsigned group_selector,
82 				unsigned func_selector);
83 	unsigned int pinconf_num_params;
84 	const struct pinconf_param *pinconf_params;
85 	int (*pinconf_set)(struct udevice *dev, unsigned pin_selector,
86 			   unsigned param, unsigned argument);
87 	int (*pinconf_group_set)(struct udevice *dev, unsigned group_selector,
88 				 unsigned param, unsigned argument);
89 	int (*set_state)(struct udevice *dev, struct udevice *config);
90 
91 	/* for pinctrl-simple */
92 	int (*set_state_simple)(struct udevice *dev, struct udevice *periph);
93 	/**
94 	 * request() - Request a particular pinctrl function
95 	 *
96 	 * This activates the selected function.
97 	 *
98 	 * @dev:	Device to adjust (UCLASS_PINCTRL)
99 	 * @func:	Function number (driver-specific)
100 	 * @return 0 if OK, -ve on error
101 	 */
102 	int (*request)(struct udevice *dev, int func, int flags);
103 
104 	/**
105 	* get_periph_id() - get the peripheral ID for a device
106 	*
107 	* This generally looks at the peripheral's device tree node to work
108 	* out the peripheral ID. The return value is normally interpreted as
109 	* enum periph_id. so long as this is defined by the platform (which it
110 	* should be).
111 	*
112 	* @dev:		Pinctrl device to use for decoding
113 	* @periph:	Device to check
114 	* @return peripheral ID of @periph, or -ENOENT on error
115 	*/
116 	int (*get_periph_id)(struct udevice *dev, struct udevice *periph);
117 
118 	/**
119 	 * get_gpio_mux() - get the mux value for a particular GPIO
120 	 *
121 	 * This allows the raw mux value for a GPIO to be obtained. It is
122 	 * useful for displaying the function being used by that GPIO, such
123 	 * as with the 'gpio' command. This function is internal to the GPIO
124 	 * subsystem and should not be used by generic code. Typically it is
125 	 * used by a GPIO driver with knowledge of the SoC pinctrl setup.
126 	 *
127 	* @dev:		Pinctrl device to use
128 	* @banknum:	GPIO bank number
129 	* @index:	GPIO index within the bank
130 	* @return mux value (SoC-specific, e.g. 0 for input, 1 for output)
131 	 */
132 	int (*get_gpio_mux)(struct udevice *dev, int banknum, int index);
133 };
134 
135 #define pinctrl_get_ops(dev)	((struct pinctrl_ops *)(dev)->driver->ops)
136 
137 /**
138  * Generic pin configuration paramters
139  *
140  * enum pin_config_param - possible pin configuration parameters
141  * @PIN_CONFIG_BIAS_BUS_HOLD: the pin will be set to weakly latch so that it
142  *	weakly drives the last value on a tristate bus, also known as a "bus
143  *	holder", "bus keeper" or "repeater". This allows another device on the
144  *	bus to change the value by driving the bus high or low and switching to
145  *	tristate. The argument is ignored.
146  * @PIN_CONFIG_BIAS_DISABLE: disable any pin bias on the pin, a
147  *	transition from say pull-up to pull-down implies that you disable
148  *	pull-up in the process, this setting disables all biasing.
149  * @PIN_CONFIG_BIAS_HIGH_IMPEDANCE: the pin will be set to a high impedance
150  *	mode, also know as "third-state" (tristate) or "high-Z" or "floating".
151  *	On output pins this effectively disconnects the pin, which is useful
152  *	if for example some other pin is going to drive the signal connected
153  *	to it for a while. Pins used for input are usually always high
154  *	impedance.
155  * @PIN_CONFIG_BIAS_PULL_DOWN: the pin will be pulled down (usually with high
156  *	impedance to GROUND). If the argument is != 0 pull-down is enabled,
157  *	if it is 0, pull-down is total, i.e. the pin is connected to GROUND.
158  * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down based
159  *	on embedded knowledge of the controller hardware, like current mux
160  *	function. The pull direction and possibly strength too will normally
161  *	be decided completely inside the hardware block and not be readable
162  *	from the kernel side.
163  *	If the argument is != 0 pull up/down is enabled, if it is 0, the
164  *	configuration is ignored. The proper way to disable it is to use
165  *	@PIN_CONFIG_BIAS_DISABLE.
166  * @PIN_CONFIG_BIAS_PULL_UP: the pin will be pulled up (usually with high
167  *	impedance to VDD). If the argument is != 0 pull-up is enabled,
168  *	if it is 0, pull-up is total, i.e. the pin is connected to VDD.
169  * @PIN_CONFIG_DRIVE_OPEN_DRAIN: the pin will be driven with open drain (open
170  *	collector) which means it is usually wired with other output ports
171  *	which are then pulled up with an external resistor. Setting this
172  *	config will enable open drain mode, the argument is ignored.
173  * @PIN_CONFIG_DRIVE_OPEN_SOURCE: the pin will be driven with open source
174  *	(open emitter). Setting this config will enable open source mode, the
175  *	argument is ignored.
176  * @PIN_CONFIG_DRIVE_PUSH_PULL: the pin will be driven actively high and
177  *	low, this is the most typical case and is typically achieved with two
178  *	active transistors on the output. Setting this config will enable
179  *	push-pull mode, the argument is ignored.
180  * @PIN_CONFIG_DRIVE_STRENGTH: the pin will sink or source at most the current
181  *	passed as argument. The argument is in mA.
182  * @PIN_CONFIG_INPUT_DEBOUNCE: this will configure the pin to debounce mode,
183  *	which means it will wait for signals to settle when reading inputs. The
184  *	argument gives the debounce time in usecs. Setting the
185  *	argument to zero turns debouncing off.
186  * @PIN_CONFIG_INPUT_ENABLE: enable the pin's input.  Note that this does not
187  *	affect the pin's ability to drive output.  1 enables input, 0 disables
188  *	input.
189  * @PIN_CONFIG_INPUT_SCHMITT: this will configure an input pin to run in
190  *	schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis,
191  *	the threshold value is given on a custom format as argument when
192  *	setting pins to this mode.
193  * @PIN_CONFIG_INPUT_SCHMITT_ENABLE: control schmitt-trigger mode on the pin.
194  *      If the argument != 0, schmitt-trigger mode is enabled. If it's 0,
195  *      schmitt-trigger mode is disabled.
196  * @PIN_CONFIG_LOW_POWER_MODE: this will configure the pin for low power
197  *	operation, if several modes of operation are supported these can be
198  *	passed in the argument on a custom form, else just use argument 1
199  *	to indicate low power mode, argument 0 turns low power mode off.
200  * @PIN_CONFIG_OUTPUT_ENABLE: this will enable the pin's output mode
201  *	without driving a value there. For most platforms this reduces to
202  *	enable the output buffers and then let the pin controller current
203  *	configuration (eg. the currently selected mux function) drive values on
204  *	the line. Use argument 1 to enable output mode, argument 0 to disable
205  *	it.
206  * @PIN_CONFIG_OUTPUT: this will configure the pin as an output and drive a
207  *	value on the line. Use argument 1 to indicate high level, argument 0 to
208  *	indicate low level. (Please see Documentation/driver-api/pinctl.rst,
209  *	section "GPIO mode pitfalls" for a discussion around this parameter.)
210  * @PIN_CONFIG_POWER_SOURCE: if the pin can select between different power
211  *	supplies, the argument to this parameter (on a custom format) tells
212  *	the driver which alternative power source to use.
213  * @PIN_CONFIG_SLEEP_HARDWARE_STATE: indicate this is sleep related state.
214  * @PIN_CONFIG_SLEW_RATE: if the pin can select slew rate, the argument to
215  *	this parameter (on a custom format) tells the driver which alternative
216  *	slew rate to use.
217  * @PIN_CONFIG_SKEW_DELAY: if the pin has programmable skew rate (on inputs)
218  *	or latch delay (on outputs) this parameter (in a custom format)
219  *	specifies the clock skew or latch delay. It typically controls how
220  *	many double inverters are put in front of the line.
221  * @PIN_CONFIG_END: this is the last enumerator for pin configurations, if
222  *	you need to pass in custom configurations to the pin controller, use
223  *	PIN_CONFIG_END+1 as the base offset.
224  * @PIN_CONFIG_MAX: this is the maximum configuration value that can be
225  *	presented using the packed format.
226  */
227 enum pin_config_param {
228 	PIN_CONFIG_BIAS_BUS_HOLD,
229 	PIN_CONFIG_BIAS_DISABLE,
230 	PIN_CONFIG_BIAS_HIGH_IMPEDANCE,
231 	PIN_CONFIG_BIAS_PULL_DOWN,
232 	PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
233 	PIN_CONFIG_BIAS_PULL_UP,
234 	PIN_CONFIG_DRIVE_OPEN_DRAIN,
235 	PIN_CONFIG_DRIVE_OPEN_SOURCE,
236 	PIN_CONFIG_DRIVE_PUSH_PULL,
237 	PIN_CONFIG_DRIVE_STRENGTH,
238 	PIN_CONFIG_INPUT_DEBOUNCE,
239 	PIN_CONFIG_INPUT_ENABLE,
240 	PIN_CONFIG_INPUT_SCHMITT,
241 	PIN_CONFIG_INPUT_SCHMITT_ENABLE,
242 	PIN_CONFIG_LOW_POWER_MODE,
243 	PIN_CONFIG_OUTPUT_ENABLE,
244 	PIN_CONFIG_OUTPUT,
245 	PIN_CONFIG_POWER_SOURCE,
246 	PIN_CONFIG_SLEEP_HARDWARE_STATE,
247 	PIN_CONFIG_SLEW_RATE,
248 	PIN_CONFIG_SKEW_DELAY,
249 	PIN_CONFIG_END = 0x7F,
250 	PIN_CONFIG_MAX = 0xFF,
251 };
252 
253 #if CONFIG_IS_ENABLED(PINCTRL_GENERIC)
254 /**
255  * pinctrl_generic_set_state() - generic set_state operation
256  * Parse the DT node of @config and its children and handle generic properties
257  * such as "pins", "groups", "functions", and pin configuration parameters.
258  *
259  * @pctldev: pinctrl device
260  * @config: config device (pseudo device), pointing a config node in DTS
261  * @return: 0 on success, or negative error code on failure
262  */
263 int pinctrl_generic_set_state(struct udevice *pctldev, struct udevice *config);
264 #else
265 static inline int pinctrl_generic_set_state(struct udevice *pctldev,
266 					    struct udevice *config)
267 {
268 	return -EINVAL;
269 }
270 #endif
271 
272 #if CONFIG_IS_ENABLED(PINCTRL)
273 /**
274  * pinctrl_select_state() - set a device to a given state
275  *
276  * @dev: peripheral device
277  * @statename: state name, like "default"
278  * @return: 0 on success, or negative error code on failure
279  */
280 int pinctrl_select_state(struct udevice *dev, const char *statename);
281 #else
282 static inline int pinctrl_select_state(struct udevice *dev,
283 				       const char *statename)
284 {
285 	return -EINVAL;
286 }
287 #endif
288 
289 /**
290  * pinctrl_request() - Request a particular pinctrl function
291  *
292  * @dev:	Device to check (UCLASS_PINCTRL)
293  * @func:	Function number (driver-specific)
294  * @flags:	Flags (driver-specific)
295  * @return 0 if OK, -ve on error
296  */
297 int pinctrl_request(struct udevice *dev, int func, int flags);
298 
299 /**
300  * pinctrl_request_noflags() - Request a particular pinctrl function
301  *
302  * This is similar to pinctrl_request() but uses 0 for @flags.
303  *
304  * @dev:	Device to check (UCLASS_PINCTRL)
305  * @func:	Function number (driver-specific)
306  * @return 0 if OK, -ve on error
307  */
308 int pinctrl_request_noflags(struct udevice *dev, int func);
309 
310 /**
311  * pinctrl_get_periph_id() - get the peripheral ID for a device
312  *
313  * This generally looks at the peripheral's device tree node to work out the
314  * peripheral ID. The return value is normally interpreted as enum periph_id.
315  * so long as this is defined by the platform (which it should be).
316  *
317  * @dev:	Pinctrl device to use for decoding
318  * @periph:	Device to check
319  * @return peripheral ID of @periph, or -ENOENT on error
320  */
321 int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph);
322 
323 /**
324  * pinctrl_decode_pin_config() - decode pin configuration flags
325  *
326  * This decodes some of the PIN_CONFIG values into flags, with each value
327  * being (1 << pin_cfg). This does not support things with values like the
328  * slew rate.
329  *
330  * @blob:	Device tree blob
331  * @node:	Node containing the PIN_CONFIG values
332  * @return decoded flag value, or -ve on error
333  */
334 int pinctrl_decode_pin_config(const void *blob, int node);
335 
336 /**
337  * pinctrl_get_gpio_mux() - get the mux value for a particular GPIO
338  *
339  * This allows the raw mux value for a GPIO to be obtained. It is
340  * useful for displaying the function being used by that GPIO, such
341  * as with the 'gpio' command. This function is internal to the GPIO
342  * subsystem and should not be used by generic code. Typically it is
343  * used by a GPIO driver with knowledge of the SoC pinctrl setup.
344  *
345  * @dev:	Pinctrl device to use
346  * @banknum:	GPIO bank number
347  * @index:	GPIO index within the bank
348  * @return mux value (SoC-specific, e.g. 0 for input, 1 for output)
349 */
350 int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index);
351 
352 #endif /* __PINCTRL_H */
353