xref: /openbmc/u-boot/include/dm/pinctrl.h (revision 1d2c0506)
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  * @PIN_CONFIG_BIAS_DISABLE: disable any pin bias on the pin, a
141  *	transition from say pull-up to pull-down implies that you disable
142  *	pull-up in the process, this setting disables all biasing.
143  * @PIN_CONFIG_BIAS_HIGH_IMPEDANCE: the pin will be set to a high impedance
144  *	mode, also know as "third-state" (tristate) or "high-Z" or "floating".
145  *	On output pins this effectively disconnects the pin, which is useful
146  *	if for example some other pin is going to drive the signal connected
147  *	to it for a while. Pins used for input are usually always high
148  *	impedance.
149  * @PIN_CONFIG_BIAS_BUS_HOLD: the pin will be set to weakly latch so that it
150  *	weakly drives the last value on a tristate bus, also known as a "bus
151  *	holder", "bus keeper" or "repeater". This allows another device on the
152  *	bus to change the value by driving the bus high or low and switching to
153  *	tristate. The argument is ignored.
154  * @PIN_CONFIG_BIAS_PULL_UP: the pin will be pulled up (usually with high
155  *	impedance to VDD). If the argument is != 0 pull-up is enabled,
156  *	if it is 0, pull-up is total, i.e. the pin is connected to VDD.
157  * @PIN_CONFIG_BIAS_PULL_DOWN: the pin will be pulled down (usually with high
158  *	impedance to GROUND). If the argument is != 0 pull-down is enabled,
159  *	if it is 0, pull-down is total, i.e. the pin is connected to GROUND.
160  * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down based
161  *	on embedded knowledge of the controller hardware, like current mux
162  *	function. The pull direction and possibly strength too will normally
163  *	be decided completely inside the hardware block and not be readable
164  *	from the kernel side.
165  *	If the argument is != 0 pull up/down is enabled, if it is 0, the
166  *	configuration is ignored. The proper way to disable it is to use
167  *	@PIN_CONFIG_BIAS_DISABLE.
168  * @PIN_CONFIG_DRIVE_PUSH_PULL: the pin will be driven actively high and
169  *	low, this is the most typical case and is typically achieved with two
170  *	active transistors on the output. Setting this config will enable
171  *	push-pull mode, the argument is ignored.
172  * @PIN_CONFIG_DRIVE_OPEN_DRAIN: the pin will be driven with open drain (open
173  *	collector) which means it is usually wired with other output ports
174  *	which are then pulled up with an external resistor. Setting this
175  *	config will enable open drain mode, the argument is ignored.
176  * @PIN_CONFIG_DRIVE_OPEN_SOURCE: the pin will be driven with open source
177  *	(open emitter). Setting this config will enable open source mode, the
178  *	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_ENABLE: enable the pin's input.  Note that this does not
182  *	affect the pin's ability to drive output.  1 enables input, 0 disables
183  *	input.
184  * @PIN_CONFIG_INPUT_SCHMITT_ENABLE: control schmitt-trigger mode on the pin.
185  *      If the argument != 0, schmitt-trigger mode is enabled. If it's 0,
186  *      schmitt-trigger mode is disabled.
187  * @PIN_CONFIG_INPUT_SCHMITT: this will configure an input pin to run in
188  *	schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis,
189  *	the threshold value is given on a custom format as argument when
190  *	setting pins to this mode.
191  * @PIN_CONFIG_INPUT_DEBOUNCE: this will configure the pin to debounce mode,
192  *	which means it will wait for signals to settle when reading inputs. The
193  *	argument gives the debounce time in usecs. Setting the
194  *	argument to zero turns debouncing off.
195  * @PIN_CONFIG_POWER_SOURCE: if the pin can select between different power
196  *	supplies, the argument to this parameter (on a custom format) tells
197  *	the driver which alternative power source to use.
198  * @PIN_CONFIG_SLEW_RATE: if the pin can select slew rate, the argument to
199  *	this parameter (on a custom format) tells the driver which alternative
200  *	slew rate to use.
201  * @PIN_CONFIG_LOW_POWER_MODE: this will configure the pin for low power
202  *	operation, if several modes of operation are supported these can be
203  *	passed in the argument on a custom form, else just use argument 1
204  *	to indicate low power mode, argument 0 turns low power mode off.
205  * @PIN_CONFIG_OUTPUT: this will configure the pin as an output. Use argument
206  *	1 to indicate high level, argument 0 to indicate low level. (Please
207  *	see Documentation/pinctrl.txt, section "GPIO mode pitfalls" for a
208  *	discussion around this parameter.)
209  * @PIN_CONFIG_END: this is the last enumerator for pin configurations, if
210  *	you need to pass in custom configurations to the pin controller, use
211  *	PIN_CONFIG_END+1 as the base offset.
212  */
213 #define PIN_CONFIG_BIAS_DISABLE			0
214 #define PIN_CONFIG_BIAS_HIGH_IMPEDANCE		1
215 #define PIN_CONFIG_BIAS_BUS_HOLD		2
216 #define PIN_CONFIG_BIAS_PULL_UP			3
217 #define PIN_CONFIG_BIAS_PULL_DOWN		4
218 #define PIN_CONFIG_BIAS_PULL_PIN_DEFAULT	5
219 #define PIN_CONFIG_DRIVE_PUSH_PULL		6
220 #define PIN_CONFIG_DRIVE_OPEN_DRAIN		7
221 #define PIN_CONFIG_DRIVE_OPEN_SOURCE		8
222 #define PIN_CONFIG_DRIVE_STRENGTH		9
223 #define PIN_CONFIG_INPUT_ENABLE			10
224 #define PIN_CONFIG_INPUT_SCHMITT_ENABLE		11
225 #define PIN_CONFIG_INPUT_SCHMITT		12
226 #define PIN_CONFIG_INPUT_DEBOUNCE		13
227 #define PIN_CONFIG_POWER_SOURCE			14
228 #define PIN_CONFIG_SLEW_RATE			15
229 #define PIN_CONFIG_LOW_POWER_MODE		16
230 #define PIN_CONFIG_OUTPUT			17
231 #define PIN_CONFIG_END				0x7FFF
232 
233 #if CONFIG_IS_ENABLED(PINCTRL_GENERIC)
234 /**
235  * pinctrl_generic_set_state() - generic set_state operation
236  * Parse the DT node of @config and its children and handle generic properties
237  * such as "pins", "groups", "functions", and pin configuration parameters.
238  *
239  * @pctldev: pinctrl device
240  * @config: config device (pseudo device), pointing a config node in DTS
241  * @return: 0 on success, or negative error code on failure
242  */
243 int pinctrl_generic_set_state(struct udevice *pctldev, struct udevice *config);
244 #else
245 static inline int pinctrl_generic_set_state(struct udevice *pctldev,
246 					    struct udevice *config)
247 {
248 	return -EINVAL;
249 }
250 #endif
251 
252 #if CONFIG_IS_ENABLED(PINCTRL)
253 /**
254  * pinctrl_select_state() - set a device to a given state
255  *
256  * @dev: peripheral device
257  * @statename: state name, like "default"
258  * @return: 0 on success, or negative error code on failure
259  */
260 int pinctrl_select_state(struct udevice *dev, const char *statename);
261 #else
262 static inline int pinctrl_select_state(struct udevice *dev,
263 				       const char *statename)
264 {
265 	return -EINVAL;
266 }
267 #endif
268 
269 /**
270  * pinctrl_request() - Request a particular pinctrl function
271  *
272  * @dev:	Device to check (UCLASS_PINCTRL)
273  * @func:	Function number (driver-specific)
274  * @flags:	Flags (driver-specific)
275  * @return 0 if OK, -ve on error
276  */
277 int pinctrl_request(struct udevice *dev, int func, int flags);
278 
279 /**
280  * pinctrl_request_noflags() - Request a particular pinctrl function
281  *
282  * This is similar to pinctrl_request() but uses 0 for @flags.
283  *
284  * @dev:	Device to check (UCLASS_PINCTRL)
285  * @func:	Function number (driver-specific)
286  * @return 0 if OK, -ve on error
287  */
288 int pinctrl_request_noflags(struct udevice *dev, int func);
289 
290 /**
291  * pinctrl_get_periph_id() - get the peripheral ID for a device
292  *
293  * This generally looks at the peripheral's device tree node to work out the
294  * peripheral ID. The return value is normally interpreted as enum periph_id.
295  * so long as this is defined by the platform (which it should be).
296  *
297  * @dev:	Pinctrl device to use for decoding
298  * @periph:	Device to check
299  * @return peripheral ID of @periph, or -ENOENT on error
300  */
301 int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph);
302 
303 /**
304  * pinctrl_decode_pin_config() - decode pin configuration flags
305  *
306  * This decodes some of the PIN_CONFIG values into flags, with each value
307  * being (1 << pin_cfg). This does not support things with values like the
308  * slew rate.
309  *
310  * @blob:	Device tree blob
311  * @node:	Node containing the PIN_CONFIG values
312  * @return decoded flag value, or -ve on error
313  */
314 int pinctrl_decode_pin_config(const void *blob, int node);
315 
316 /**
317  * pinctrl_get_gpio_mux() - get the mux value for a particular GPIO
318  *
319  * This allows the raw mux value for a GPIO to be obtained. It is
320  * useful for displaying the function being used by that GPIO, such
321  * as with the 'gpio' command. This function is internal to the GPIO
322  * subsystem and should not be used by generic code. Typically it is
323  * used by a GPIO driver with knowledge of the SoC pinctrl setup.
324  *
325  * @dev:	Pinctrl device to use
326  * @banknum:	GPIO bank number
327  * @index:	GPIO index within the bank
328  * @return mux value (SoC-specific, e.g. 0 for input, 1 for output)
329 */
330 int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index);
331 
332 #endif /* __PINCTRL_H */
333