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
12 struct ofnode_phandle_args;
13
14 /*
15 * Generic GPIO API for U-Boot
16 *
17 * --
18 * NB: This is deprecated. Please use the driver model functions instead:
19 *
20 * - gpio_request_by_name()
21 * - dm_gpio_get_value() etc.
22 *
23 * For now we need a dm_ prefix on some functions to avoid name collision.
24 * --
25 *
26 * GPIOs are numbered from 0 to GPIO_COUNT-1 which value is defined
27 * by the SOC/architecture.
28 *
29 * Each GPIO can be an input or output. If an input then its value can
30 * be read as 0 or 1. If an output then its value can be set to 0 or 1.
31 * If you try to write an input then the value is undefined. If you try
32 * to read an output, barring something very unusual, you will get
33 * back the value of the output that you previously set.
34 *
35 * In some cases the operation may fail, for example if the GPIO number
36 * is out of range, or the GPIO is not available because its pin is
37 * being used by another function. In that case, functions may return
38 * an error value of -1.
39 */
40
41 /**
42 * @deprecated Please use driver model instead
43 * Request a GPIO. This should be called before any of the other functions
44 * are used on this GPIO.
45 *
46 * Note: With driver model, the label is allocated so there is no need for
47 * the caller to preserve it.
48 *
49 * @param gpio GPIO number
50 * @param label User label for this GPIO
51 * @return 0 if ok, -1 on error
52 */
53 int gpio_request(unsigned gpio, const char *label);
54
55 /**
56 * @deprecated Please use driver model instead
57 * Stop using the GPIO. This function should not alter pin configuration.
58 *
59 * @param gpio GPIO number
60 * @return 0 if ok, -1 on error
61 */
62 int gpio_free(unsigned gpio);
63
64 /**
65 * @deprecated Please use driver model instead
66 * Make a GPIO an input.
67 *
68 * @param gpio GPIO number
69 * @return 0 if ok, -1 on error
70 */
71 int gpio_direction_input(unsigned gpio);
72
73 /**
74 * @deprecated Please use driver model instead
75 * Make a GPIO an output, and set its value.
76 *
77 * @param gpio GPIO number
78 * @param value GPIO value (0 for low or 1 for high)
79 * @return 0 if ok, -1 on error
80 */
81 int gpio_direction_output(unsigned gpio, int value);
82
83 /**
84 * @deprecated Please use driver model instead
85 * Get a GPIO's value. This will work whether the GPIO is an input
86 * or an output.
87 *
88 * @param gpio GPIO number
89 * @return 0 if low, 1 if high, -1 on error
90 */
91 int gpio_get_value(unsigned gpio);
92
93 /**
94 * @deprecated Please use driver model instead
95 * Set an output GPIO's value. The GPIO must already be an output or
96 * this function may have no effect.
97 *
98 * @param gpio GPIO number
99 * @param value GPIO value (0 for low or 1 for high)
100 * @return 0 if ok, -1 on error
101 */
102 int gpio_set_value(unsigned gpio, int value);
103
104 /* State of a GPIO, as reported by get_function() */
105 enum gpio_func_t {
106 GPIOF_INPUT = 0,
107 GPIOF_OUTPUT,
108 GPIOF_UNUSED, /* Not claimed */
109 GPIOF_UNKNOWN, /* Not known */
110 GPIOF_FUNC, /* Not used as a GPIO */
111
112 GPIOF_COUNT,
113 };
114
115 struct udevice;
116
117 struct gpio_desc {
118 struct udevice *dev; /* Device, NULL for invalid GPIO */
119 unsigned long flags;
120 #define GPIOD_REQUESTED (1 << 0) /* Requested/claimed */
121 #define GPIOD_IS_OUT (1 << 1) /* GPIO is an output */
122 #define GPIOD_IS_IN (1 << 2) /* GPIO is an input */
123 #define GPIOD_ACTIVE_LOW (1 << 3) /* value has active low */
124 #define GPIOD_IS_OUT_ACTIVE (1 << 4) /* set output active */
125
126 uint offset; /* GPIO offset within the device */
127 /*
128 * We could consider adding the GPIO label in here. Possibly we could
129 * use this structure for internal GPIO information.
130 */
131 };
132
133 /**
134 * dm_gpio_is_valid() - Check if a GPIO is valid
135 *
136 * @desc: GPIO description containing device, offset and flags,
137 * previously returned by gpio_request_by_name()
138 * @return true if valid, false if not
139 */
dm_gpio_is_valid(const struct gpio_desc * desc)140 static inline bool dm_gpio_is_valid(const struct gpio_desc *desc)
141 {
142 return desc->dev != NULL;
143 }
144
145 /**
146 * gpio_get_status() - get the current GPIO status as a string
147 *
148 * Obtain the current GPIO status as a string which can be presented to the
149 * user. A typical string is:
150 *
151 * "b4: in: 1 [x] sdmmc_cd"
152 *
153 * which means this is GPIO bank b, offset 4, currently set to input, current
154 * value 1, [x] means that it is requested and the owner is 'sdmmc_cd'
155 *
156 * TODO(sjg@chromium.org): This should use struct gpio_desc
157 *
158 * @dev: Device to check
159 * @offset: Offset of device GPIO to check
160 * @buf: Place to put string
161 * @buffsize: Size of string including \0
162 */
163 int gpio_get_status(struct udevice *dev, int offset, char *buf, int buffsize);
164
165 /**
166 * gpio_get_function() - get the current function for a GPIO pin
167 *
168 * Note this returns GPIOF_UNUSED if the GPIO is not requested.
169 *
170 * TODO(sjg@chromium.org): This should use struct gpio_desc
171 *
172 * @dev: Device to check
173 * @offset: Offset of device GPIO to check
174 * @namep: If non-NULL, this is set to the name given when the GPIO
175 * was requested, or -1 if it has not been requested
176 * @return -ENODATA if the driver returned an unknown function,
177 * -ENODEV if the device is not active, -EINVAL if the offset is invalid.
178 * GPIOF_UNUSED if the GPIO has not been requested. Otherwise returns the
179 * function from enum gpio_func_t.
180 */
181 int gpio_get_function(struct udevice *dev, int offset, const char **namep);
182
183 /**
184 * gpio_get_raw_function() - get the current raw function for a GPIO pin
185 *
186 * Note this does not return GPIOF_UNUSED - it will always return the GPIO
187 * driver's view of a pin function, even if it is not correctly set up.
188 *
189 * TODO(sjg@chromium.org): This should use struct gpio_desc
190 *
191 * @dev: Device to check
192 * @offset: Offset of device GPIO to check
193 * @namep: If non-NULL, this is set to the name given when the GPIO
194 * was requested, or -1 if it has not been requested
195 * @return -ENODATA if the driver returned an unknown function,
196 * -ENODEV if the device is not active, -EINVAL if the offset is invalid.
197 * Otherwise returns the function from enum gpio_func_t.
198 */
199 int gpio_get_raw_function(struct udevice *dev, int offset, const char **namep);
200
201 /**
202 * gpio_requestf() - request a GPIO using a format string for the owner
203 *
204 * This is a helper function for gpio_request(). It allows you to provide
205 * a printf()-format string for the GPIO owner. It calls gpio_request() with
206 * the string that is created
207 */
208 int gpio_requestf(unsigned gpio, const char *fmt, ...)
209 __attribute__ ((format (__printf__, 2, 3)));
210
211 struct fdtdec_phandle_args;
212
213 /**
214 * gpio_xlate_offs_flags() - implementation for common use of dm_gpio_ops.xlate
215 *
216 * This routine sets the offset field to args[0] and the flags field to
217 * GPIOD_ACTIVE_LOW if the GPIO_ACTIVE_LOW flag is present in args[1].
218 */
219 int gpio_xlate_offs_flags(struct udevice *dev, struct gpio_desc *desc,
220 struct ofnode_phandle_args *args);
221
222 /**
223 * struct struct dm_gpio_ops - Driver model GPIO operations
224 *
225 * Refer to functions above for description. These function largely copy
226 * the old API.
227 *
228 * This is trying to be close to Linux GPIO API. Once the U-Boot uses the
229 * new DM GPIO API, this should be really easy to flip over to the Linux
230 * GPIO API-alike interface.
231 *
232 * Also it would be useful to standardise additional functions like
233 * pullup, slew rate and drive strength.
234 *
235 * gpio_request() and gpio_free() are optional - if NULL then they will
236 * not be called.
237 *
238 * Note that @offset is the offset from the base GPIO of the device. So
239 * offset 0 is the device's first GPIO and offset o-1 is the last GPIO,
240 * where o is the number of GPIO lines controlled by the device. A device
241 * is typically used to control a single bank of GPIOs. Within complex
242 * SoCs there may be many banks and therefore many devices all referring
243 * to the different IO addresses within the SoC.
244 *
245 * The uclass combines all GPIO devices together to provide a consistent
246 * numbering from 0 to n-1, where n is the number of GPIOs in total across
247 * all devices. Be careful not to confuse offset with gpio in the parameters.
248 */
249 struct dm_gpio_ops {
250 int (*request)(struct udevice *dev, unsigned offset, const char *label);
251 int (*free)(struct udevice *dev, unsigned offset);
252 int (*direction_input)(struct udevice *dev, unsigned offset);
253 int (*direction_output)(struct udevice *dev, unsigned offset,
254 int value);
255 int (*get_value)(struct udevice *dev, unsigned offset);
256 int (*set_value)(struct udevice *dev, unsigned offset, int value);
257 int (*get_open_drain)(struct udevice *dev, unsigned offset);
258 int (*set_open_drain)(struct udevice *dev, unsigned offset, int value);
259 /**
260 * get_function() Get the GPIO function
261 *
262 * @dev: Device to check
263 * @offset: GPIO offset within that device
264 * @return current function - GPIOF_...
265 */
266 int (*get_function)(struct udevice *dev, unsigned offset);
267
268 /**
269 * xlate() - Translate phandle arguments into a GPIO description
270 *
271 * This function should set up the fields in desc according to the
272 * information in the arguments. The uclass will have set up:
273 *
274 * @desc->dev to @dev
275 * @desc->flags to 0
276 * @desc->offset to 0
277 *
278 * This method is optional and defaults to gpio_xlate_offs_flags,
279 * which will parse offset and the GPIO_ACTIVE_LOW flag in the first
280 * two arguments.
281 *
282 * Note that @dev is passed in as a parameter to follow driver model
283 * uclass conventions, even though it is already available as
284 * desc->dev.
285 *
286 * @dev: GPIO device
287 * @desc: Place to put GPIO description
288 * @args: Arguments provided in description
289 * @return 0 if OK, -ve on error
290 */
291 int (*xlate)(struct udevice *dev, struct gpio_desc *desc,
292 struct ofnode_phandle_args *args);
293 };
294
295 /**
296 * struct gpio_dev_priv - information about a device used by the uclass
297 *
298 * The uclass combines all active GPIO devices into a unified numbering
299 * scheme. To do this it maintains some private information about each
300 * device.
301 *
302 * To implement driver model support in your GPIO driver, add a probe
303 * handler, and set @gpio_count and @bank_name correctly in that handler.
304 * This tells the uclass the name of the GPIO bank and the number of GPIOs
305 * it contains.
306 *
307 * @bank_name: Name of the GPIO device (e.g 'a' means GPIOs will be called
308 * 'A0', 'A1', etc.
309 * @gpio_count: Number of GPIOs in this device
310 * @gpio_base: Base GPIO number for this device. For the first active device
311 * this will be 0; the numbering for others will follow sequentially so that
312 * @gpio_base for device 1 will equal the number of GPIOs in device 0.
313 * @name: Array of pointers to the name for each GPIO in this bank. The
314 * value of the pointer will be NULL if the GPIO has not been claimed.
315 */
316 struct gpio_dev_priv {
317 const char *bank_name;
318 unsigned gpio_count;
319 unsigned gpio_base;
320 char **name;
321 };
322
323 /* Access the GPIO operations for a device */
324 #define gpio_get_ops(dev) ((struct dm_gpio_ops *)(dev)->driver->ops)
325
326 /**
327 * gpio_get_bank_info - Return information about a GPIO bank/device
328 *
329 * This looks up a device and returns both its GPIO base name and the number
330 * of GPIOs it controls.
331 *
332 * @dev: Device to look up
333 * @offset_count: Returns number of GPIOs within this bank
334 * @return bank name of this device
335 */
336 const char *gpio_get_bank_info(struct udevice *dev, int *offset_count);
337
338 /**
339 * dm_gpio_lookup_name() - Look up a named GPIO and return its description
340 *
341 * The name of a GPIO is typically its bank name followed by a number from 0.
342 * For example A0 is the first GPIO in bank A. Each bank is a separate driver
343 * model device.
344 *
345 * @name: Name to look up
346 * @desc: Returns description, on success
347 * @return 0 if OK, -ve on error
348 */
349 int dm_gpio_lookup_name(const char *name, struct gpio_desc *desc);
350
351 /**
352 * gpio_hog_lookup_name() - Look up a named GPIO and return the gpio descr.
353 *
354 * @name: Name to look up
355 * @desc: Returns GPIO description, on success, else NULL
356 * @return: Returns 0 if OK, else -ENODEV
357 */
358 int gpio_hog_lookup_name(const char *name, struct gpio_desc **desc);
359
360 /**
361 * gpio_hog_probe_all() - probe all gpio devices with
362 * gpio-hog subnodes.
363 *
364 * @return: Returns return value from device_probe()
365 */
366 int gpio_hog_probe_all(void);
367
368 /**
369 * gpio_lookup_name - Look up a GPIO name and return its details
370 *
371 * This is used to convert a named GPIO into a device, offset and GPIO
372 * number.
373 *
374 * @name: GPIO name to look up
375 * @devp: Returns pointer to device which contains this GPIO
376 * @offsetp: Returns the offset number within this device
377 * @gpiop: Returns the absolute GPIO number, numbered from 0
378 */
379 int gpio_lookup_name(const char *name, struct udevice **devp,
380 unsigned int *offsetp, unsigned int *gpiop);
381
382 /**
383 * gpio_get_values_as_int() - Turn the values of a list of GPIOs into an int
384 *
385 * This puts the value of the first GPIO into bit 0, the second into bit 1,
386 * etc. then returns the resulting integer.
387 *
388 * @gpio_list: List of GPIOs to collect
389 * @return resulting integer value, or -ve on error
390 */
391 int gpio_get_values_as_int(const int *gpio_list);
392
393 /**
394 * dm_gpio_get_values_as_int() - Turn the values of a list of GPIOs into an int
395 *
396 * This puts the value of the first GPIO into bit 0, the second into bit 1,
397 * etc. then returns the resulting integer.
398 *
399 * @desc_list: List of GPIOs to collect
400 * @count: Number of GPIOs
401 * @return resulting integer value, or -ve on error
402 */
403 int dm_gpio_get_values_as_int(const struct gpio_desc *desc_list, int count);
404
405 /**
406 * gpio_claim_vector() - claim a number of GPIOs for input
407 *
408 * @gpio_num_array: array of gpios to claim, terminated by -1
409 * @fmt: format string for GPIO names, e.g. "board_id%d"
410 * @return 0 if OK, -ve on error
411 */
412 int gpio_claim_vector(const int *gpio_num_array, const char *fmt);
413
414 /**
415 * gpio_request_by_name() - Locate and request a GPIO by name
416 *
417 * This operates by looking up the given list name in the device (device
418 * tree property) and requesting the GPIO for use. The property must exist
419 * in @dev's node.
420 *
421 * Use @flags to specify whether the GPIO should be an input or output. In
422 * principle this can also come from the device tree binding but most
423 * bindings don't provide this information. Specifically, when the GPIO uclass
424 * calls the xlate() method, it can return default flags, which are then
425 * ORed with this @flags.
426 *
427 * If we find that requesting the GPIO is not always needed we could add a
428 * new function or a new GPIOD_NO_REQUEST flag.
429 *
430 * At present driver model has no reference counting so if one device
431 * requests a GPIO which subsequently is unbound, the @desc->dev pointer
432 * will be invalid. However this will only happen if the GPIO device is
433 * unbound, not if it is removed, so this seems like a reasonable limitation
434 * for now. There is no real use case for unbinding drivers in normal
435 * operation.
436 *
437 * The device tree binding is doc/device-tree-bindings/gpio/gpio.txt in
438 * generate terms and each specific device may add additional details in
439 * a binding file in the same directory.
440 *
441 * @dev: Device requesting the GPIO
442 * @list_name: Name of GPIO list (e.g. "board-id-gpios")
443 * @index: Index number of the GPIO in that list use request (0=first)
444 * @desc: Returns GPIO description information. If there is no such
445 * GPIO, dev->dev will be NULL.
446 * @flags: Indicates the GPIO input/output settings (GPIOD_...)
447 * @return 0 if OK, -ENOENT if the GPIO does not exist, -EINVAL if there is
448 * something wrong with the list, or other -ve for another error (e.g.
449 * -EBUSY if a GPIO was already requested)
450 */
451 int gpio_request_by_name(struct udevice *dev, const char *list_name,
452 int index, struct gpio_desc *desc, int flags);
453
454 /**
455 * gpio_request_list_by_name() - Request a list of GPIOs
456 *
457 * Reads all the GPIOs from a list and requests them. See
458 * gpio_request_by_name() for additional details. Lists should not be
459 * misused to hold unrelated or optional GPIOs. They should only be used
460 * for things like parallel data lines. A zero phandle terminates the list
461 * the list.
462 *
463 * This function will either succeed, and request all GPIOs in the list, or
464 * fail and request none (it will free already-requested GPIOs in case of
465 * an error part-way through).
466 *
467 * @dev: Device requesting the GPIO
468 * @list_name: Name of GPIO list (e.g. "board-id-gpios")
469 * @desc_list: Returns a list of GPIO description information
470 * @max_count: Maximum number of GPIOs to return (@desc_list must be at least
471 * this big)
472 * @flags: Indicates the GPIO input/output settings (GPIOD_...)
473 * @return number of GPIOs requested, or -ve on error
474 */
475 int gpio_request_list_by_name(struct udevice *dev, const char *list_name,
476 struct gpio_desc *desc_list, int max_count,
477 int flags);
478
479 /**
480 * dm_gpio_request() - manually request a GPIO
481 *
482 * Note: This function should only be used for testing / debugging. Instead.
483 * use gpio_request_by_name() to pull GPIOs from the device tree.
484 *
485 * @desc: GPIO description of GPIO to request (see dm_gpio_lookup_name())
486 * @label: Label to attach to the GPIO while claimed
487 * @return 0 if OK, -ve on error
488 */
489 int dm_gpio_request(struct gpio_desc *desc, const char *label);
490
491 /**
492 * gpio_get_list_count() - Returns the number of GPIOs in a list
493 *
494 * Counts the GPIOs in a list. See gpio_request_by_name() for additional
495 * details.
496 *
497 * @dev: Device requesting the GPIO
498 * @list_name: Name of GPIO list (e.g. "board-id-gpios")
499 * @return number of GPIOs (0 for an empty property) or -ENOENT if the list
500 * does not exist
501 */
502 int gpio_get_list_count(struct udevice *dev, const char *list_name);
503
504 /**
505 * gpio_request_by_name_nodev() - request GPIOs without a device
506 *
507 * This is a version of gpio_request_list_by_name() that does not use a
508 * device. Avoid it unless the caller is not yet using driver model
509 */
510 int gpio_request_by_name_nodev(ofnode node, const char *list_name, int index,
511 struct gpio_desc *desc, int flags);
512
513 /**
514 * gpio_request_list_by_name_nodev() - request GPIOs without a device
515 *
516 * This is a version of gpio_request_list_by_name() that does not use a
517 * device. Avoid it unless the caller is not yet using driver model
518 */
519 int gpio_request_list_by_name_nodev(ofnode node, const char *list_name,
520 struct gpio_desc *desc_list, int max_count,
521 int flags);
522
523 /**
524 * gpio_dev_request_index() - request single GPIO from gpio device
525 *
526 * @dev: GPIO device
527 * @nodename: Name of node for which gpio gets requested, used
528 * for the gpio label name
529 * @list_name: Name of GPIO list (e.g. "board-id-gpios")
530 * @index: Index number of the GPIO in that list use request (0=first)
531 * @flags: GPIOD_* flags
532 * @dtflags: GPIO flags read from DT defined see GPIOD_*
533 * @desc: returns GPIO descriptor filled from this function
534 * @return: return value from gpio_request_tail()
535 */
536 int gpio_dev_request_index(struct udevice *dev, const char *nodename,
537 char *list_name, int index, int flags,
538 int dtflags, struct gpio_desc *desc);
539
540 /**
541 * dm_gpio_free() - Free a single GPIO
542 *
543 * This frees a single GPIOs previously returned from gpio_request_by_name().
544 *
545 * @dev: Device which requested the GPIO
546 * @desc: GPIO to free
547 * @return 0 if OK, -ve on error
548 */
549 int dm_gpio_free(struct udevice *dev, struct gpio_desc *desc);
550
551 /**
552 * gpio_free_list() - Free a list of GPIOs
553 *
554 * This frees a list of GPIOs previously returned from
555 * gpio_request_list_by_name().
556 *
557 * @dev: Device which requested the GPIOs
558 * @desc: List of GPIOs to free
559 * @count: Number of GPIOs in the list
560 * @return 0 if OK, -ve on error
561 */
562 int gpio_free_list(struct udevice *dev, struct gpio_desc *desc, int count);
563
564 /**
565 * gpio_free_list_nodev() - free GPIOs without a device
566 *
567 * This is a version of gpio_free_list() that does not use a
568 * device. Avoid it unless the caller is not yet using driver model
569 */
570 int gpio_free_list_nodev(struct gpio_desc *desc, int count);
571
572 /**
573 * dm_gpio_get_value() - Get the value of a GPIO
574 *
575 * This is the driver model version of the existing gpio_get_value() function
576 * and should be used instead of that.
577 *
578 * For now, these functions have a dm_ prefix since they conflict with
579 * existing names.
580 *
581 * @desc: GPIO description containing device, offset and flags,
582 * previously returned by gpio_request_by_name()
583 * @return GPIO value (0 for inactive, 1 for active) or -ve on error
584 */
585 int dm_gpio_get_value(const struct gpio_desc *desc);
586
587 int dm_gpio_set_value(const struct gpio_desc *desc, int value);
588
589 /**
590 * dm_gpio_get_open_drain() - Check if open-drain-mode of a GPIO is active
591 *
592 * This checks if open-drain-mode for a GPIO is enabled or not. This method is
593 * optional.
594 *
595 * @desc: GPIO description containing device, offset and flags,
596 * previously returned by gpio_request_by_name()
597 * @return Value of open drain mode for GPIO (0 for inactive, 1 for active) or
598 * -ve on error
599 */
600 int dm_gpio_get_open_drain(struct gpio_desc *desc);
601
602 /**
603 * dm_gpio_set_open_drain() - Switch open-drain-mode of a GPIO on or off
604 *
605 * This enables or disables open-drain mode for a GPIO. This method is
606 * optional; if the driver does not support it, nothing happens when the method
607 * is called.
608 *
609 * In open-drain mode, instead of actively driving the output (Push-pull
610 * output), the GPIO's pin is connected to the collector (for a NPN transistor)
611 * or the drain (for a MOSFET) of a transistor, respectively. The pin then
612 * either forms an open circuit or a connection to ground, depending on the
613 * state of the transistor.
614 *
615 * @desc: GPIO description containing device, offset and flags,
616 * previously returned by gpio_request_by_name()
617 * @return 0 if OK, -ve on error
618 */
619 int dm_gpio_set_open_drain(struct gpio_desc *desc, int value);
620
621 /**
622 * dm_gpio_set_dir() - Set the direction for a GPIO
623 *
624 * This sets up the direction according tot the provided flags. It will do
625 * nothing unless the direction is actually specified.
626 *
627 * @desc: GPIO description containing device, offset and flags,
628 * previously returned by gpio_request_by_name()
629 * @return 0 if OK, -ve on error
630 */
631 int dm_gpio_set_dir(struct gpio_desc *desc);
632
633 /**
634 * dm_gpio_set_dir_flags() - Set direction using specific flags
635 *
636 * This is like dm_gpio_set_dir() except that the flags value is provided
637 * instead of being used from desc->flags. This is needed because in many
638 * cases the GPIO description does not include direction information.
639 * Note that desc->flags is updated by this function.
640 *
641 * @desc: GPIO description containing device, offset and flags,
642 * previously returned by gpio_request_by_name()
643 * @flags: New flags to use
644 * @return 0 if OK, -ve on error, in which case desc->flags is not updated
645 */
646 int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags);
647
648 /**
649 * gpio_get_number() - Get the global GPIO number of a GPIO
650 *
651 * This should only be used for debugging or interest. It returns the number
652 * that should be used for gpio_get_value() etc. to access this GPIO.
653 *
654 * @desc: GPIO description containing device, offset and flags,
655 * previously returned by gpio_request_by_name()
656 * @return GPIO number, or -ve if not found
657 */
658 int gpio_get_number(const struct gpio_desc *desc);
659
660 #endif /* _ASM_GENERIC_GPIO_H_ */
661