1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * Copyright (c) 2011 The Chromium OS Authors.
4 * Copyright (c) 2011, NVIDIA Corp. All rights reserved.
5 */
6
7#ifndef _ASM_GENERIC_GPIO_H_
8#define _ASM_GENERIC_GPIO_H_
9
10#include <dm/ofnode.h>
11#include <linux/bitops.h>
12
13struct acpi_gpio;
14struct ofnode_phandle_args;
15
16/*
17 * Generic GPIO API for U-Boot
18 *
19 * --
20 * NB: This is deprecated. Please use the driver model functions instead:
21 *
22 *    - gpio_request_by_name()
23 *    - dm_gpio_get_value() etc.
24 *
25 * For now we need a dm_ prefix on some functions to avoid name collision.
26 * --
27 *
28 * GPIOs are numbered from 0 to GPIO_COUNT-1 which value is defined
29 * by the SOC/architecture.
30 *
31 * Each GPIO can be an input or output. If an input then its value can
32 * be read as 0 or 1. If an output then its value can be set to 0 or 1.
33 * If you try to write an input then the value is undefined. If you try
34 * to read an output, barring something very unusual,  you will get
35 * back the value of the output that you previously set.
36 *
37 * In some cases the operation may fail, for example if the GPIO number
38 * is out of range, or the GPIO is not available because its pin is
39 * being used by another function. In that case, functions may return
40 * an error value of -1.
41 */
42
43/**
44 * @deprecated	Please use driver model instead
45 * Request a GPIO. This should be called before any of the other functions
46 * are used on this GPIO.
47 *
48 * Note: With driver model, the label is allocated so there is no need for
49 * the caller to preserve it.
50 *
51 * @param gpio	GPIO number
52 * @param label	User label for this GPIO
53 * Return: 0 if ok, -1 on error
54 */
55int gpio_request(unsigned gpio, const char *label);
56
57/**
58 * @deprecated	Please use driver model instead
59 * Stop using the GPIO.  This function should not alter pin configuration.
60 *
61 * @param gpio	GPIO number
62 * Return: 0 if ok, -1 on error
63 */
64int gpio_free(unsigned gpio);
65
66/**
67 * @deprecated	Please use driver model instead
68 * Make a GPIO an input.
69 *
70 * @param gpio	GPIO number
71 * Return: 0 if ok, -1 on error
72 */
73int gpio_direction_input(unsigned gpio);
74
75/**
76 * @deprecated	Please use driver model instead
77 * Make a GPIO an output, and set its value.
78 *
79 * @param gpio	GPIO number
80 * @param value	GPIO value (0 for low or 1 for high)
81 * Return: 0 if ok, -1 on error
82 */
83int gpio_direction_output(unsigned gpio, int value);
84
85/**
86 * @deprecated	Please use driver model instead
87 * Get a GPIO's value. This will work whether the GPIO is an input
88 * or an output.
89 *
90 * @param gpio	GPIO number
91 * Return: 0 if low, 1 if high, -1 on error
92 */
93int gpio_get_value(unsigned gpio);
94
95/**
96 * @deprecated	Please use driver model instead
97 * Set an output GPIO's value. The GPIO must already be an output or
98 * this function may have no effect.
99 *
100 * @param gpio	GPIO number
101 * @param value	GPIO value (0 for low or 1 for high)
102 * Return: 0 if ok, -1 on error
103 */
104int gpio_set_value(unsigned gpio, int value);
105
106/* State of a GPIO, as reported by get_function() */
107enum gpio_func_t {
108	GPIOF_INPUT = 0,
109	GPIOF_OUTPUT,
110	GPIOF_UNUSED,		/* Not claimed */
111	GPIOF_UNKNOWN,		/* Not known */
112	GPIOF_FUNC,		/* Not used as a GPIO */
113
114	GPIOF_COUNT,
115};
116
117struct udevice;
118
119struct gpio_desc {
120	struct udevice *dev;	/* Device, NULL for invalid GPIO */
121	unsigned long flags;
122#define GPIOD_IS_OUT		BIT(1)	/* GPIO is an output */
123#define GPIOD_IS_IN		BIT(2)	/* GPIO is an input */
124#define GPIOD_ACTIVE_LOW	BIT(3)	/* GPIO is active when value is low */
125#define GPIOD_IS_OUT_ACTIVE	BIT(4)	/* set output active */
126#define GPIOD_OPEN_DRAIN	BIT(5)	/* GPIO is open drain type */
127#define GPIOD_OPEN_SOURCE	BIT(6)	/* GPIO is open source type */
128#define GPIOD_PULL_UP		BIT(7)	/* GPIO has pull-up enabled */
129#define GPIOD_PULL_DOWN		BIT(8)	/* GPIO has pull-down enabled */
130#define GPIOD_IS_AF		BIT(9)	/* GPIO is an alternate function */
131
132/* Flags for updating the above */
133#define GPIOD_MASK_DIR		(GPIOD_IS_OUT | GPIOD_IS_IN | \
134					GPIOD_IS_OUT_ACTIVE)
135#define GPIOD_MASK_DSTYPE	(GPIOD_OPEN_DRAIN | GPIOD_OPEN_SOURCE)
136#define GPIOD_MASK_PULL		(GPIOD_PULL_UP | GPIOD_PULL_DOWN)
137
138	uint offset;		/* GPIO offset within the device */
139	/*
140	 * We could consider adding the GPIO label in here. Possibly we could
141	 * use this structure for internal GPIO information.
142	 */
143};
144
145/**
146 * dm_gpio_is_valid() - Check if a GPIO is valid
147 *
148 * @desc:	GPIO description containing device, offset and flags,
149 *		previously returned by gpio_request_by_name()
150 * Return: true if valid, false if not
151 */
152static inline bool dm_gpio_is_valid(const struct gpio_desc *desc)
153{
154	return desc->dev != NULL;
155}
156
157/**
158 * gpio_get_status() - get the current GPIO status as a string
159 *
160 * Obtain the current GPIO status as a string which can be presented to the
161 * user. A typical string is:
162 *
163 * "b4:  in: 1 [x] sdmmc_cd"
164 *
165 * which means this is GPIO bank b, offset 4, currently set to input, current
166 * value 1, [x] means that it is requested and the owner is 'sdmmc_cd'
167 *
168 * TODO(sjg@chromium.org): This should use struct gpio_desc
169 *
170 * @dev:	Device to check
171 * @offset:	Offset of device GPIO to check
172 * @buf:	Place to put string
173 * @buffsize:	Size of string including \0
174 */
175int gpio_get_status(struct udevice *dev, int offset, char *buf, int buffsize);
176
177/**
178 * gpio_get_function() - get the current function for a GPIO pin
179 *
180 * Note this returns GPIOF_UNUSED if the GPIO is not requested.
181 *
182 * TODO(sjg@chromium.org): This should use struct gpio_desc
183 *
184 * @dev:	Device to check
185 * @offset:	Offset of device GPIO to check
186 * @namep:	If non-NULL, this is set to the name given when the GPIO
187 *		was requested, or -1 if it has not been requested
188 * Return:  -ENODATA if the driver returned an unknown function,
189 * -ENODEV if the device is not active, -EINVAL if the offset is invalid.
190 * GPIOF_UNUSED if the GPIO has not been requested. Otherwise returns the
191 * function from enum gpio_func_t.
192 */
193int gpio_get_function(struct udevice *dev, int offset, const char **namep);
194
195/**
196 * gpio_get_raw_function() - get the current raw function for a GPIO pin
197 *
198 * Note this does not return GPIOF_UNUSED - it will always return the GPIO
199 * driver's view of a pin function, even if it is not correctly set up.
200 *
201 * TODO(sjg@chromium.org): This should use struct gpio_desc
202 *
203 * @dev:	Device to check
204 * @offset:	Offset of device GPIO to check
205 * @namep:	If non-NULL, this is set to the name given when the GPIO
206 *		was requested, or -1 if it has not been requested
207 * Return:  -ENODATA if the driver returned an unknown function,
208 * -ENODEV if the device is not active, -EINVAL if the offset is invalid.
209 * Otherwise returns the function from enum gpio_func_t.
210 */
211int gpio_get_raw_function(struct udevice *dev, int offset, const char **namep);
212
213/**
214 * gpio_requestf() - request a GPIO using a format string for the owner
215 *
216 * This is a helper function for gpio_request(). It allows you to provide
217 * a printf()-format string for the GPIO owner. It calls gpio_request() with
218 * the string that is created
219 */
220int gpio_requestf(unsigned gpio, const char *fmt, ...)
221		__attribute__ ((format (__printf__, 2, 3)));
222
223struct fdtdec_phandle_args;
224
225/**
226 * gpio_flags_xlate() - convert DT flags to internal flags
227 *
228 * This routine converts the GPIO_* flags from the generic DT binding to the
229 * GPIOD_* flags used internally. It can be called from driver xlate functions.
230 */
231unsigned long gpio_flags_xlate(uint32_t arg);
232
233/**
234 * gpio_xlate_offs_flags() - implementation for common use of dm_gpio_ops.xlate
235 *
236 * This routine sets the offset field to args[0] and the flags field to
237 * GPIOD_ACTIVE_LOW if the GPIO_ACTIVE_LOW flag is present in args[1].
238 */
239int gpio_xlate_offs_flags(struct udevice *dev, struct gpio_desc *desc,
240			  struct ofnode_phandle_args *args);
241
242/**
243 * struct struct dm_gpio_ops - Driver model GPIO operations
244 *
245 * Refer to functions above for description. These function largely copy
246 * the old API.
247 *
248 * This is trying to be close to Linux GPIO API. Once the U-Boot uses the
249 * new DM GPIO API, this should be really easy to flip over to the Linux
250 * GPIO API-alike interface.
251 *
252 * Also it would be useful to standardise additional functions like
253 * pullup, slew rate and drive strength.
254 *
255 * gpio_request() and gpio_free() are optional - if NULL then they will
256 * not be called.
257 *
258 * Note that @offset is the offset from the base GPIO of the device. So
259 * offset 0 is the device's first GPIO and offset o-1 is the last GPIO,
260 * where o is the number of GPIO lines controlled by the device. A device
261 * is typically used to control a single bank of GPIOs. Within complex
262 * SoCs there may be many banks and therefore many devices all referring
263 * to the different IO addresses within the SoC.
264 *
265 * The uclass combines all GPIO devices together to provide a consistent
266 * numbering from 0 to n-1, where n is the number of GPIOs in total across
267 * all devices. Be careful not to confuse offset with gpio in the parameters.
268 */
269struct dm_gpio_ops {
270	int (*request)(struct udevice *dev, unsigned offset, const char *label);
271	int (*rfree)(struct udevice *dev, unsigned int offset);
272
273	/**
274	 * direction_input() - deprecated
275	 *
276	 * Equivalent to set_flags(...GPIOD_IS_IN)
277	 */
278	int (*direction_input)(struct udevice *dev, unsigned offset);
279
280	/**
281	 * direction_output() - deprecated
282	 *
283	 * Equivalent to set_flags(...GPIOD_IS_OUT) with GPIOD_IS_OUT_ACTIVE
284	 * also set if @value
285	 */
286	int (*direction_output)(struct udevice *dev, unsigned offset,
287				int value);
288
289	int (*get_value)(struct udevice *dev, unsigned offset);
290
291	/**
292	 * set_value() - Sets the GPIO value of an output
293	 *
294	 * If the driver provides an @set_flags() method then that is used
295	 * in preference to this, with GPIOD_IS_OUT_ACTIVE set according to
296	 * @value.
297	 */
298	int (*set_value)(struct udevice *dev, unsigned offset, int value);
299	/**
300	 * get_function() Get the GPIO function
301	 *
302	 * @dev:     Device to check
303	 * @offset:  GPIO offset within that device
304	 * @return current function - GPIOF_...
305	 */
306	int (*get_function)(struct udevice *dev, unsigned offset);
307
308	/**
309	 * xlate() - Translate phandle arguments into a GPIO description
310	 *
311	 * This function should set up the fields in desc according to the
312	 * information in the arguments. The uclass will have set up:
313	 *
314	 *   @desc->dev to @dev
315	 *   @desc->flags to 0
316	 *   @desc->offset to 0
317	 *
318	 * This method is optional and defaults to gpio_xlate_offs_flags,
319	 * which will parse offset and the GPIO_ACTIVE_LOW flag in the first
320	 * two arguments.
321	 *
322	 * Note that @dev is passed in as a parameter to follow driver model
323	 * uclass conventions, even though it is already available as
324	 * desc->dev.
325	 *
326	 * @dev:	GPIO device
327	 * @desc:	Place to put GPIO description
328	 * @args:	Arguments provided in description
329	 * @return 0 if OK, -ve on error
330	 */
331	int (*xlate)(struct udevice *dev, struct gpio_desc *desc,
332		     struct ofnode_phandle_args *args);
333
334	/**
335	 * set_flags() - Adjust GPIO flags
336	 *
337	 * This function should set up the GPIO configuration according to the
338	 * information provided by @flags.
339	 *
340	 * If any flags cannot be set (e.g. the driver or hardware does not
341	 * support them or this particular GPIO does not have the requested
342	 * feature), the driver should return -EINVAL.
343	 *
344	 * The uclass checks that flags do not obviously conflict (e.g. input
345	 * and output). If the driver finds other conflicts it should return
346	 * -ERECALLCONFLICT
347	 *
348	 * Note that GPIOD_ACTIVE_LOW should be ignored, since the uclass
349	 * adjusts for it automatically. For example, for an output GPIO,
350	 * GPIOD_ACTIVE_LOW causes GPIOD_IS_OUT_ACTIVE to be inverted by the
351	 * uclass, so the driver always sees the value that should be set at the
352	 * pin (1=high, 0=low).
353	 *
354	 * This method is required and should be implemented by new drivers. At
355	 * some point, it will supersede direction_input() and
356	 * direction_output(), which wil be removed.
357	 *
358	 * @dev:	GPIO device
359	 * @offset:	GPIO offset within that device
360	 * @flags:	New flags value (GPIOD_...)
361	 *
362	 * @return 0 if OK, -EINVAL if unsupported, -ERECALLCONFLICT if flags
363	 *	conflict in some *	non-obvious way and were not applied,
364	 *	other -ve on error
365	 */
366	int (*set_flags)(struct udevice *dev, unsigned int offset, ulong flags);
367
368	/**
369	 * get_flags() - Get GPIO flags
370	 *
371	 * This function return the GPIO flags used. It should read this from
372	 * the hardware directly.
373	 *
374	 * This method is optional.
375	 *
376	 * @dev:	GPIO device
377	 * @offset:	GPIO offset within that device
378	 * @flagsp:	place to put the current flags value
379	 * @return 0 if OK, -ve on error
380	 */
381	int (*get_flags)(struct udevice *dev, unsigned int offset,
382			 ulong *flagsp);
383
384#if CONFIG_IS_ENABLED(ACPIGEN)
385	/**
386	 * get_acpi() - Get the ACPI info for a GPIO
387	 *
388	 * This converts a GPIO to an ACPI structure for adding to the ACPI
389	 * tables.
390	 *
391	 * @desc:	GPIO description to convert
392	 * @gpio:	Output ACPI GPIO information
393	 * @return ACPI pin number or -ve on error
394	 */
395	int (*get_acpi)(const struct gpio_desc *desc, struct acpi_gpio *gpio);
396#endif
397};
398
399/**
400 * struct gpio_dev_priv - information about a device used by the uclass
401 *
402 * The uclass combines all active GPIO devices into a unified numbering
403 * scheme. To do this it maintains some private information about each
404 * device.
405 *
406 * To implement driver model support in your GPIO driver, add a probe
407 * handler, and set @gpio_count and @bank_name correctly in that handler.
408 * This tells the uclass the name of the GPIO bank and the number of GPIOs
409 * it contains.
410 *
411 * @bank_name: Name of the GPIO device (e.g 'a' means GPIOs will be called
412 * 'A0', 'A1', etc.
413 * @gpio_count: Number of GPIOs in this device
414 * @gpio_base: Base GPIO number for this device. For the first active device
415 * this will be 0; the numbering for others will follow sequentially so that
416 * @gpio_base for device 1 will equal the number of GPIOs in device 0.
417 * @claimed: Array of bits indicating which GPIOs in the bank are claimed.
418 * @name: Array of pointers to the name for each GPIO in this bank. The
419 * value of the pointer will be NULL if the GPIO has not been claimed.
420 */
421struct gpio_dev_priv {
422	const char *bank_name;
423	unsigned gpio_count;
424	unsigned gpio_base;
425	u32 *claimed;
426	char **name;
427};
428
429/* Access the GPIO operations for a device */
430#define gpio_get_ops(dev)	((struct dm_gpio_ops *)(dev)->driver->ops)
431
432/**
433 * gpio_get_bank_info - Return information about a GPIO bank/device
434 *
435 * This looks up a device and returns both its GPIO base name and the number
436 * of GPIOs it controls.
437 *
438 * @dev: Device to look up
439 * @offset_count: Returns number of GPIOs within this bank
440 * Return: bank name of this device
441 */
442const char *gpio_get_bank_info(struct udevice *dev, int *offset_count);
443
444/**
445 * dm_gpio_lookup_name() - Look up a named GPIO and return its description
446 *
447 * The name of a GPIO is typically its bank name followed by a number from 0.
448 * For example A0 is the first GPIO in bank A. Each bank is a separate driver
449 * model device.
450 *
451 * @name:	Name to look up
452 * @desc:	Returns description, on success
453 * Return: 0 if OK, -ve on error
454 */
455int dm_gpio_lookup_name(const char *name, struct gpio_desc *desc);
456
457/**
458 * gpio_hog_lookup_name() - Look up a named GPIO and return the gpio descr.
459 *
460 * @name:	Name to look up
461 * @desc:	Returns GPIO description, on success, else NULL
462 * @return:	Returns 0 if OK, else -ENODEV
463 */
464int gpio_hog_lookup_name(const char *name, struct gpio_desc **desc);
465
466/**
467 * gpio_lookup_name - Look up a GPIO name and return its details
468 *
469 * This is used to convert a named GPIO into a device, offset and GPIO
470 * number.
471 *
472 * @name: GPIO name to look up
473 * @devp: Returns pointer to device which contains this GPIO
474 * @offsetp: Returns the offset number within this device
475 * @gpiop: Returns the absolute GPIO number, numbered from 0
476 */
477int gpio_lookup_name(const char *name, struct udevice **devp,
478		     unsigned int *offsetp, unsigned int *gpiop);
479
480/**
481 * gpio_get_values_as_int() - Turn the values of a list of GPIOs into an int
482 *
483 * This puts the value of the first GPIO into bit 0, the second into bit 1,
484 * etc. then returns the resulting integer.
485 *
486 * @gpio_list: List of GPIOs to collect
487 * Return: resulting integer value, or -ve on error
488 */
489int gpio_get_values_as_int(const int *gpio_list);
490
491/**
492 * dm_gpio_get_values_as_int() - Turn the values of a list of GPIOs into an int
493 *
494 * This puts the value of the first GPIO into bit 0, the second into bit 1,
495 * etc. then returns the resulting integer.
496 *
497 * @desc_list: List of GPIOs to collect
498 * @count: Number of GPIOs
499 * Return: resulting integer value, or -ve on error
500 */
501int dm_gpio_get_values_as_int(const struct gpio_desc *desc_list, int count);
502
503/**
504 * dm_gpio_get_values_as_int_base3() - Create a base-3 int from a list of GPIOs
505 *
506 * This uses pull-ups/pull-downs to figure out whether a GPIO line is externally
507 * pulled down, pulled up or floating. This allows three different strap values
508 * for each pin:
509 *    0 : external pull-down
510 *    1 : external pull-up
511 *    2 : floating
512 *
513 * With this it is possible to obtain more combinations from the same number of
514 * strapping pins, when compared to dm_gpio_get_values_as_int(). The external
515 * pull resistors should be made stronger that the internal SoC pull resistors,
516 * for this to work.
517 *
518 * With 2 pins, 6 combinations are possible, compared with 4
519 * With 3 pins, 27 are possible, compared with 8
520 *
521 * @desc_list: List of GPIOs to collect
522 * @count: Number of GPIOs
523 * Return: resulting integer value, or -ve on error
524 */
525int dm_gpio_get_values_as_int_base3(struct gpio_desc *desc_list,
526				    int count);
527
528/**
529 * gpio_claim_vector() - claim a number of GPIOs for input
530 *
531 * @gpio_num_array:	array of gpios to claim, terminated by -1
532 * @fmt:		format string for GPIO names, e.g. "board_id%d"
533 * Return: 0 if OK, -ve on error
534 */
535int gpio_claim_vector(const int *gpio_num_array, const char *fmt);
536
537/**
538 * gpio_request_by_name() - Locate and request a GPIO by name
539 *
540 * This operates by looking up the given list name in the device (device
541 * tree property) and requesting the GPIO for use. The property must exist
542 * in @dev's node.
543 *
544 * Use @flags to specify whether the GPIO should be an input or output. In
545 * principle this can also come from the device tree binding but most
546 * bindings don't provide this information. Specifically, when the GPIO uclass
547 * calls the xlate() method, it can return default flags, which are then
548 * ORed with this @flags.
549 *
550 * If we find that requesting the GPIO is not always needed we could add a
551 * new function or a new GPIOD_NO_REQUEST flag.
552 *
553 * At present driver model has no reference counting so if one device
554 * requests a GPIO which subsequently is unbound, the @desc->dev pointer
555 * will be invalid. However this will only happen if the GPIO device is
556 * unbound, not if it is removed, so this seems like a reasonable limitation
557 * for now. There is no real use case for unbinding drivers in normal
558 * operation.
559 *
560 * The device tree binding is doc/device-tree-bindings/gpio/gpio.txt in
561 * generate terms and each specific device may add additional details in
562 * a binding file in the same directory.
563 *
564 * @dev:	Device requesting the GPIO
565 * @list_name:	Name of GPIO list (e.g. "board-id-gpios")
566 * @index:	Index number of the GPIO in that list use request (0=first)
567 * @desc:	Returns GPIO description information. If there is no such
568 *		GPIO, @desc->dev will be NULL.
569 * @flags:	Indicates the GPIO input/output settings (GPIOD_...)
570 * Return: 0 if OK, -ENOENT if the GPIO does not exist, -EINVAL if there is
571 * something wrong with the list, or other -ve for another error (e.g.
572 * -EBUSY if a GPIO was already requested)
573 */
574int gpio_request_by_name(struct udevice *dev, const char *list_name,
575			 int index, struct gpio_desc *desc, int flags);
576
577/* gpio_request_by_line_name - Locate and request a GPIO by line name
578 *
579 * Request a GPIO using the offset of the provided line name in the
580 * gpio-line-names property found in the OF node of the GPIO udevice.
581 *
582 * This allows boards to implement common behaviours using GPIOs while not
583 * requiring specific GPIO offsets be used.
584 *
585 * @dev:        An instance of a GPIO controller udevice, or NULL to search
586 *              all GPIO controller devices
587 * @line_name:	The name of the GPIO (e.g. "bmc-secure-boot")
588 * @desc:	A GPIO descriptor that is populated with the requested GPIO
589 *              upon return
590 * @flags:	The GPIO settings apply to the request
591 * @return 0 if the named line was found and requested successfully, or a
592 * negative error code if the GPIO cannot be found or the request failed.
593 */
594int gpio_request_by_line_name(struct udevice *dev, const char *line_name,
595			      struct gpio_desc *desc, int flags);
596
597/**
598 * gpio_request_list_by_name() - Request a list of GPIOs
599 *
600 * Reads all the GPIOs from a list and requests them. See
601 * gpio_request_by_name() for additional details. Lists should not be
602 * misused to hold unrelated or optional GPIOs. They should only be used
603 * for things like parallel data lines. A zero phandle terminates the list
604 * the list.
605 *
606 * This function will either succeed, and request all GPIOs in the list, or
607 * fail and request none (it will free already-requested GPIOs in case of
608 * an error part-way through).
609 *
610 * @dev:	Device requesting the GPIO
611 * @list_name:	Name of GPIO list (e.g. "board-id-gpios")
612 * @desc_list:	Returns a list of GPIO description information
613 * @max_count:	Maximum number of GPIOs to return (@desc_list must be at least
614 *		this big)
615 * @flags:	Indicates the GPIO input/output settings (GPIOD_...)
616 * Return: number of GPIOs requested, or -ve on error
617 */
618int gpio_request_list_by_name(struct udevice *dev, const char *list_name,
619			      struct gpio_desc *desc_list, int max_count,
620			      int flags);
621
622/**
623 * dm_gpio_request() - manually request a GPIO
624 *
625 * Note: This function should only be used for testing / debugging. Instead.
626 * use gpio_request_by_name() to pull GPIOs from the device tree.
627 *
628 * @desc:	GPIO description of GPIO to request (see dm_gpio_lookup_name())
629 * @label:	Label to attach to the GPIO while claimed
630 * Return: 0 if OK, -ve on error
631 */
632int dm_gpio_request(struct gpio_desc *desc, const char *label);
633
634struct phandle_2_arg;
635int gpio_request_by_phandle(struct udevice *dev,
636			    const struct phandle_2_arg *cells,
637			    struct gpio_desc *desc, int flags);
638
639/**
640 * gpio_get_list_count() - Returns the number of GPIOs in a list
641 *
642 * Counts the GPIOs in a list. See gpio_request_by_name() for additional
643 * details.
644 *
645 * @dev:	Device requesting the GPIO
646 * @list_name:	Name of GPIO list (e.g. "board-id-gpios")
647 * Return: number of GPIOs (0 for an empty property) or -ENOENT if the list
648 * does not exist
649 */
650int gpio_get_list_count(struct udevice *dev, const char *list_name);
651
652/**
653 * gpio_request_by_name_nodev() - request GPIOs without a device
654 *
655 * This is a version of gpio_request_list_by_name() that does not use a
656 * device. Avoid it unless the caller is not yet using driver model
657 */
658int gpio_request_by_name_nodev(ofnode node, const char *list_name, int index,
659			       struct gpio_desc *desc, int flags);
660
661/**
662 * gpio_request_list_by_name_nodev() - request GPIOs without a device
663 *
664 * This is a version of gpio_request_list_by_name() that does not use a
665 * device. Avoid it unless the caller is not yet using driver model
666 */
667int gpio_request_list_by_name_nodev(ofnode node, const char *list_name,
668				    struct gpio_desc *desc_list, int max_count,
669				    int flags);
670
671/**
672 * gpio_dev_request_index() - request single GPIO from gpio device
673 *
674 * @dev:	GPIO device
675 * @nodename:	Name of node for which gpio gets requested, used
676 *		for the gpio label name
677 * @list_name:	Name of GPIO list (e.g. "board-id-gpios")
678 * @index:	Index number of the GPIO in that list use request (0=first)
679 * @flags:	GPIOD_* flags
680 * @dtflags:	GPIO flags read from DT defined see GPIOD_*
681 * @desc:	returns GPIO descriptor filled from this function
682 * @return:	return value from gpio_request_tail()
683 */
684int gpio_dev_request_index(struct udevice *dev, const char *nodename,
685			   char *list_name, int index, int flags,
686			   int dtflags, struct gpio_desc *desc);
687
688/**
689 * dm_gpio_free() - Free a single GPIO
690 *
691 * This frees a single GPIOs previously returned from gpio_request_by_name().
692 *
693 * @dev:	Device which requested the GPIO
694 * @desc:	GPIO to free
695 * Return: 0 if OK, -ve on error
696 */
697int dm_gpio_free(struct udevice *dev, struct gpio_desc *desc);
698
699/**
700 * gpio_free_list() - Free a list of GPIOs
701 *
702 * This frees a list of GPIOs previously returned from
703 * gpio_request_list_by_name().
704 *
705 * @dev:	Device which requested the GPIOs
706 * @desc:	List of GPIOs to free
707 * @count:	Number of GPIOs in the list
708 * Return: 0 if OK, -ve on error
709 */
710int gpio_free_list(struct udevice *dev, struct gpio_desc *desc, int count);
711
712/**
713 * gpio_free_list_nodev() - free GPIOs without a device
714 *
715 * This is a version of gpio_free_list() that does not use a
716 * device. Avoid it unless the caller is not yet using driver model
717 */
718int gpio_free_list_nodev(struct gpio_desc *desc, int count);
719
720/**
721 * dm_gpio_get_value() - Get the value of a GPIO
722 *
723 * This is the driver model version of the existing gpio_get_value() function
724 * and should be used instead of that.
725 *
726 * For now, these functions have a dm_ prefix since they conflict with
727 * existing names.
728 *
729 * @desc:	GPIO description containing device, offset and flags,
730 *		previously returned by gpio_request_by_name()
731 * Return: GPIO value (0 for inactive, 1 for active) or -ve on error
732 */
733int dm_gpio_get_value(const struct gpio_desc *desc);
734
735int dm_gpio_set_value(const struct gpio_desc *desc, int value);
736
737/**
738 * dm_gpio_clrset_flags() - Update flags
739 *
740 * This updates the flags as directled. Note that desc->flags is updated by this
741 * function on success. If any changes cannot be made, best efforts are made.
742 *
743 * By use of @clr and @set any of flags can be individually updated, or left
744 * alone
745 *
746 * @desc:	GPIO description containing device, offset and flags,
747 *		previously returned by gpio_request_by_name()
748 * @clr:	Flags to clear (GPIOD_...)
749 * @set:	Flags to set (GPIOD_...)
750 * Return: 0 if OK, -EINVAL if the flags had obvious conflicts,
751 * -ERECALLCONFLICT if there was a non-obvious hardware conflict when attempting
752 * to set the flags
753 */
754int dm_gpio_clrset_flags(struct gpio_desc *desc, ulong clr, ulong set);
755
756/**
757 * dm_gpio_set_dir_flags() - Set direction using description and added flags
758 *
759 * This sets up the direction according to the provided flags and the GPIO
760 * description (desc->flags) which include direction information.
761 * Note that desc->flags is updated by this function.
762 *
763 * @desc:	GPIO description containing device, offset and flags,
764 *		previously returned by gpio_request_by_name()
765 * @flags:	New flags to use
766 * Return: 0 if OK, -ve on error, in which case desc->flags is not updated
767 */
768int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags);
769
770/**
771 * dm_gpios_clrset_flags() - Sets flags for a set of GPIOs
772 *
773 * This clears and sets flags individually for each GPIO.
774 *
775 * @desc:	List of GPIOs to update
776 * @count:	Number of GPIOs in the list
777 * @clr:	Flags to clear (GPIOD_...), e.g. GPIOD_MASK_DIR if you are
778 *		changing the direction
779 * @set:	Flags to set (GPIOD_...)
780 * Return: 0 if OK, -ve on error
781 */
782int dm_gpios_clrset_flags(struct gpio_desc *desc, int count, ulong clr,
783			  ulong set);
784
785/**
786 * dm_gpio_get_flags() - Get flags
787 *
788 * Read the current flags
789 *
790 * @desc:	GPIO description containing device, offset and flags,
791 *		previously returned by gpio_request_by_name()
792 * @flags:	place to put the used flags
793 * Return: 0 if OK, -ve on error, in which case desc->flags is not updated
794 */
795int dm_gpio_get_flags(struct gpio_desc *desc, ulong *flags);
796
797/**
798 * gpio_get_number() - Get the global GPIO number of a GPIO
799 *
800 * This should only be used for debugging or interest. It returns the number
801 * that should be used for gpio_get_value() etc. to access this GPIO.
802 *
803 * @desc:	GPIO description containing device, offset and flags,
804 *		previously returned by gpio_request_by_name()
805 * Return: GPIO number, or -ve if not found
806 */
807int gpio_get_number(const struct gpio_desc *desc);
808
809/**
810 * gpio_get_acpi() - Get the ACPI pin for a GPIO
811 *
812 * This converts a GPIO to an ACPI pin number for adding to the ACPI
813 * tables. If the GPIO is invalid, the pin_count and pins[0] are set to 0
814 *
815 * @desc:	GPIO description to convert
816 * @gpio:	Output ACPI GPIO information
817 * Return: ACPI pin number or -ve on error
818 */
819int gpio_get_acpi(const struct gpio_desc *desc, struct acpi_gpio *gpio);
820
821/**
822 * devm_gpiod_get_index - Resource-managed gpiod_get()
823 * @dev:	GPIO consumer
824 * @con_id:	function within the GPIO consumer
825 * @index:	index of the GPIO to obtain in the consumer
826 * @flags:	optional GPIO initialization flags
827 *
828 * Managed gpiod_get(). GPIO descriptors returned from this function are
829 * automatically disposed on device unbind.
830 * Return the GPIO descriptor corresponding to the function con_id of device
831 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
832 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
833 */
834struct gpio_desc *devm_gpiod_get_index(struct udevice *dev, const char *id,
835				       unsigned int index, int flags);
836
837#define devm_gpiod_get(dev, id, flags) devm_gpiod_get_index(dev, id, 0, flags)
838/**
839 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
840 * @dev: GPIO consumer, can be NULL for system-global GPIOs
841 * @con_id: function within the GPIO consumer
842 * @index:	index of the GPIO to obtain in the consumer
843 * @flags: optional GPIO initialization flags
844 *
845 * This is equivalent to devm_gpiod_get(), except that when no GPIO was
846 * assigned to the requested function it will return NULL. This is convenient
847 * for drivers that need to handle optional GPIOs.
848 */
849struct gpio_desc *devm_gpiod_get_index_optional(struct udevice *dev,
850						const char *id,
851						unsigned int index,
852						int flags);
853
854#define devm_gpiod_get_optional(dev, id, flags) \
855	devm_gpiod_get_index_optional(dev, id, 0, flags)
856
857/**
858 * devm_gpiod_put - Resource-managed gpiod_put()
859 * @dev:	GPIO consumer
860 * @desc:	GPIO descriptor to dispose of
861 *
862 * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
863 * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
864 * will be disposed of by the resource management code.
865 */
866void devm_gpiod_put(struct udevice *dev, struct gpio_desc *desc);
867
868#endif	/* _ASM_GENERIC_GPIO_H_ */
869