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Simon Glass9c35f0e2011-10-07 13:53:50 +00001/*
2 * Copyright (c) 2011 The Chromium OS Authors.
Joe Hershberger334b2322011-11-11 15:55:35 -06003 * Copyright (c) 2011, NVIDIA Corp. All rights reserved.
Wolfgang Denkd79de1d2013-07-08 09:37:19 +02004 * SPDX-License-Identifier: GPL-2.0+
Simon Glass9c35f0e2011-10-07 13:53:50 +00005 */
6
Joe Hershberger334b2322011-11-11 15:55:35 -06007#ifndef _ASM_GENERIC_GPIO_H_
8#define _ASM_GENERIC_GPIO_H_
9
Simon Glass9c35f0e2011-10-07 13:53:50 +000010/*
11 * Generic GPIO API for U-Boot
12 *
Simon Glassaf0bb3e2015-01-05 20:05:30 -070013 * --
14 * NB: This is deprecated. Please use the driver model functions instead:
15 *
16 * - gpio_request_by_name()
17 * - dm_gpio_get_value() etc.
18 *
19 * For now we need a dm_ prefix on some functions to avoid name collision.
20 * --
21 *
Simon Glass9c35f0e2011-10-07 13:53:50 +000022 * GPIOs are numbered from 0 to GPIO_COUNT-1 which value is defined
23 * by the SOC/architecture.
24 *
25 * Each GPIO can be an input or output. If an input then its value can
26 * be read as 0 or 1. If an output then its value can be set to 0 or 1.
27 * If you try to write an input then the value is undefined. If you try
28 * to read an output, barring something very unusual, you will get
29 * back the value of the output that you previously set.
30 *
31 * In some cases the operation may fail, for example if the GPIO number
32 * is out of range, or the GPIO is not available because its pin is
33 * being used by another function. In that case, functions may return
34 * an error value of -1.
35 */
Joe Hershberger334b2322011-11-11 15:55:35 -060036
37/**
Simon Glassaf0bb3e2015-01-05 20:05:30 -070038 * @deprecated Please use driver model instead
Marcel Ziswiler8a523c52014-10-10 17:31:41 +020039 * Request a GPIO. This should be called before any of the other functions
40 * are used on this GPIO.
Joe Hershberger334b2322011-11-11 15:55:35 -060041 *
Simon Glass0f4517d2014-10-04 11:29:42 -060042 * Note: With driver model, the label is allocated so there is no need for
43 * the caller to preserve it.
44 *
Nikita Kiryanovd9a67172012-11-26 23:06:32 +000045 * @param gp GPIO number
46 * @param label User label for this GPIO
Joe Hershberger334b2322011-11-11 15:55:35 -060047 * @return 0 if ok, -1 on error
48 */
49int gpio_request(unsigned gpio, const char *label);
Simon Glass9c35f0e2011-10-07 13:53:50 +000050
51/**
Simon Glassaf0bb3e2015-01-05 20:05:30 -070052 * @deprecated Please use driver model instead
Joe Hershberger334b2322011-11-11 15:55:35 -060053 * Stop using the GPIO. This function should not alter pin configuration.
54 *
55 * @param gpio GPIO number
56 * @return 0 if ok, -1 on error
57 */
58int gpio_free(unsigned gpio);
59
60/**
Simon Glassaf0bb3e2015-01-05 20:05:30 -070061 * @deprecated Please use driver model instead
Simon Glass9c35f0e2011-10-07 13:53:50 +000062 * Make a GPIO an input.
63 *
Joe Hershberger334b2322011-11-11 15:55:35 -060064 * @param gpio GPIO number
Simon Glass9c35f0e2011-10-07 13:53:50 +000065 * @return 0 if ok, -1 on error
66 */
Joe Hershberger334b2322011-11-11 15:55:35 -060067int gpio_direction_input(unsigned gpio);
Simon Glass9c35f0e2011-10-07 13:53:50 +000068
69/**
Simon Glassaf0bb3e2015-01-05 20:05:30 -070070 * @deprecated Please use driver model instead
Simon Glass9c35f0e2011-10-07 13:53:50 +000071 * Make a GPIO an output, and set its value.
72 *
Joe Hershberger334b2322011-11-11 15:55:35 -060073 * @param gpio GPIO number
Simon Glass9c35f0e2011-10-07 13:53:50 +000074 * @param value GPIO value (0 for low or 1 for high)
75 * @return 0 if ok, -1 on error
76 */
Joe Hershberger334b2322011-11-11 15:55:35 -060077int gpio_direction_output(unsigned gpio, int value);
Simon Glass9c35f0e2011-10-07 13:53:50 +000078
79/**
Simon Glassaf0bb3e2015-01-05 20:05:30 -070080 * @deprecated Please use driver model instead
Simon Glass9c35f0e2011-10-07 13:53:50 +000081 * Get a GPIO's value. This will work whether the GPIO is an input
82 * or an output.
83 *
Joe Hershberger334b2322011-11-11 15:55:35 -060084 * @param gpio GPIO number
Simon Glass9c35f0e2011-10-07 13:53:50 +000085 * @return 0 if low, 1 if high, -1 on error
86 */
Joe Hershberger334b2322011-11-11 15:55:35 -060087int gpio_get_value(unsigned gpio);
Simon Glass9c35f0e2011-10-07 13:53:50 +000088
89/**
Simon Glassaf0bb3e2015-01-05 20:05:30 -070090 * @deprecated Please use driver model instead
Joe Hershberger334b2322011-11-11 15:55:35 -060091 * Set an output GPIO's value. The GPIO must already be an output or
Simon Glass9c35f0e2011-10-07 13:53:50 +000092 * this function may have no effect.
93 *
Joe Hershberger334b2322011-11-11 15:55:35 -060094 * @param gpio GPIO number
Simon Glass9c35f0e2011-10-07 13:53:50 +000095 * @param value GPIO value (0 for low or 1 for high)
96 * @return 0 if ok, -1 on error
97 */
Joe Hershberger334b2322011-11-11 15:55:35 -060098int gpio_set_value(unsigned gpio, int value);
Simon Glasse821d182014-02-26 15:59:24 -070099
Simon Glass2d6b9232014-08-11 09:23:52 -0600100/* State of a GPIO, as reported by get_function() */
Simon Glass6e5e6dd2014-10-04 11:29:43 -0600101enum gpio_func_t {
Simon Glasse821d182014-02-26 15:59:24 -0700102 GPIOF_INPUT = 0,
103 GPIOF_OUTPUT,
Simon Glass2d6b9232014-08-11 09:23:52 -0600104 GPIOF_UNUSED, /* Not claimed */
105 GPIOF_UNKNOWN, /* Not known */
106 GPIOF_FUNC, /* Not used as a GPIO */
107
108 GPIOF_COUNT,
Simon Glasse821d182014-02-26 15:59:24 -0700109};
110
Heiko Schocherb74fcb42014-05-22 12:43:05 +0200111struct udevice;
Simon Glasse821d182014-02-26 15:59:24 -0700112
Simon Glassce555292015-01-05 20:05:27 -0700113struct gpio_desc {
114 struct udevice *dev; /* Device, NULL for invalid GPIO */
115 unsigned long flags;
116#define GPIOD_REQUESTED (1 << 0) /* Requested/claimed */
117#define GPIOD_IS_OUT (1 << 1) /* GPIO is an output */
Simon Glass518827e2015-05-04 11:31:01 -0600118#define GPIOD_IS_IN (1 << 2) /* GPIO is an input */
Simon Glassce555292015-01-05 20:05:27 -0700119#define GPIOD_ACTIVE_LOW (1 << 3) /* value has active low */
120#define GPIOD_IS_OUT_ACTIVE (1 << 4) /* set output active */
121
122 uint offset; /* GPIO offset within the device */
123 /*
124 * We could consider adding the GPIO label in here. Possibly we could
125 * use this structure for internal GPIO information.
126 */
127};
128
Simon Glasse821d182014-02-26 15:59:24 -0700129/**
Simon Glass16e10402015-01-05 20:05:29 -0700130 * dm_gpio_is_valid() - Check if a GPIO is gpio_is_valie
131 *
132 * @desc: GPIO description containing device, offset and flags,
133 * previously returned by gpio_request_by_name()
134 * @return true if valid, false if not
135 */
136static inline bool dm_gpio_is_valid(struct gpio_desc *desc)
137{
138 return desc->dev != NULL;
139}
140
141/**
Simon Glass6b1ef592014-10-04 11:29:44 -0600142 * gpio_get_status() - get the current GPIO status as a string
143 *
144 * Obtain the current GPIO status as a string which can be presented to the
145 * user. A typical string is:
146 *
147 * "b4: in: 1 [x] sdmmc_cd"
148 *
149 * which means this is GPIO bank b, offset 4, currently set to input, current
150 * value 1, [x] means that it is requested and the owner is 'sdmmc_cd'
151 *
Simon Glassaf0bb3e2015-01-05 20:05:30 -0700152 * TODO(sjg@chromium.org): This should use struct gpio_desc
153 *
Simon Glass6b1ef592014-10-04 11:29:44 -0600154 * @dev: Device to check
155 * @offset: Offset of device GPIO to check
156 * @buf: Place to put string
157 * @buffsize: Size of string including \0
158 */
159int gpio_get_status(struct udevice *dev, int offset, char *buf, int buffsize);
160
161/**
Simon Glass6e5e6dd2014-10-04 11:29:43 -0600162 * gpio_get_function() - get the current function for a GPIO pin
163 *
164 * Note this returns GPIOF_UNUSED if the GPIO is not requested.
165 *
Simon Glassaf0bb3e2015-01-05 20:05:30 -0700166 * TODO(sjg@chromium.org): This should use struct gpio_desc
167 *
Simon Glass6e5e6dd2014-10-04 11:29:43 -0600168 * @dev: Device to check
169 * @offset: Offset of device GPIO to check
170 * @namep: If non-NULL, this is set to the nane given when the GPIO
171 * was requested, or -1 if it has not been requested
172 * @return -ENODATA if the driver returned an unknown function,
173 * -ENODEV if the device is not active, -EINVAL if the offset is invalid.
174 * GPIOF_UNUSED if the GPIO has not been requested. Otherwise returns the
175 * function from enum gpio_func_t.
176 */
177int gpio_get_function(struct udevice *dev, int offset, const char **namep);
178
179/**
180 * gpio_get_raw_function() - get the current raw function for a GPIO pin
181 *
182 * Note this does not return GPIOF_UNUSED - it will always return the GPIO
183 * driver's view of a pin function, even if it is not correctly set up.
184 *
Simon Glassaf0bb3e2015-01-05 20:05:30 -0700185 * TODO(sjg@chromium.org): This should use struct gpio_desc
186 *
Simon Glass6e5e6dd2014-10-04 11:29:43 -0600187 * @dev: Device to check
188 * @offset: Offset of device GPIO to check
189 * @namep: If non-NULL, this is set to the nane given when the GPIO
190 * was requested, or -1 if it has not been requested
191 * @return -ENODATA if the driver returned an unknown function,
192 * -ENODEV if the device is not active, -EINVAL if the offset is invalid.
193 * Otherwise returns the function from enum gpio_func_t.
194 */
195int gpio_get_raw_function(struct udevice *dev, int offset, const char **namep);
196
197/**
Simon Glass1b27d602014-10-04 11:29:49 -0600198 * gpio_requestf() - request a GPIO using a format string for the owner
199 *
200 * This is a helper function for gpio_request(). It allows you to provide
201 * a printf()-format string for the GPIO owner. It calls gpio_request() with
202 * the string that is created
203 */
204int gpio_requestf(unsigned gpio, const char *fmt, ...)
205 __attribute__ ((format (__printf__, 2, 3)));
206
Simon Glassd3322bb2015-01-05 20:05:28 -0700207struct fdtdec_phandle_args;
208
Simon Glass1b27d602014-10-04 11:29:49 -0600209/**
Simon Glasse821d182014-02-26 15:59:24 -0700210 * struct struct dm_gpio_ops - Driver model GPIO operations
211 *
212 * Refer to functions above for description. These function largely copy
213 * the old API.
214 *
215 * This is trying to be close to Linux GPIO API. Once the U-Boot uses the
216 * new DM GPIO API, this should be really easy to flip over to the Linux
217 * GPIO API-alike interface.
218 *
Marcel Ziswiler8a523c52014-10-10 17:31:41 +0200219 * Also it would be useful to standardise additional functions like
Simon Glasse821d182014-02-26 15:59:24 -0700220 * pullup, slew rate and drive strength.
221 *
222 * gpio_request)( and gpio_free() are optional - if NULL then they will
223 * not be called.
224 *
225 * Note that @offset is the offset from the base GPIO of the device. So
226 * offset 0 is the device's first GPIO and offset o-1 is the last GPIO,
227 * where o is the number of GPIO lines controlled by the device. A device
228 * is typically used to control a single bank of GPIOs. Within complex
229 * SoCs there may be many banks and therefore many devices all referring
230 * to the different IO addresses within the SoC.
231 *
Marcel Ziswiler8a523c52014-10-10 17:31:41 +0200232 * The uclass combines all GPIO devices together to provide a consistent
Simon Glasse821d182014-02-26 15:59:24 -0700233 * numbering from 0 to n-1, where n is the number of GPIOs in total across
234 * all devices. Be careful not to confuse offset with gpio in the parameters.
235 */
236struct dm_gpio_ops {
Heiko Schocherb74fcb42014-05-22 12:43:05 +0200237 int (*request)(struct udevice *dev, unsigned offset, const char *label);
238 int (*free)(struct udevice *dev, unsigned offset);
239 int (*direction_input)(struct udevice *dev, unsigned offset);
240 int (*direction_output)(struct udevice *dev, unsigned offset,
Simon Glasse821d182014-02-26 15:59:24 -0700241 int value);
Heiko Schocherb74fcb42014-05-22 12:43:05 +0200242 int (*get_value)(struct udevice *dev, unsigned offset);
243 int (*set_value)(struct udevice *dev, unsigned offset, int value);
Simon Glass2d6b9232014-08-11 09:23:52 -0600244 /**
245 * get_function() Get the GPIO function
246 *
247 * @dev: Device to check
248 * @offset: GPIO offset within that device
249 * @return current function - GPIOF_...
250 */
Heiko Schocherb74fcb42014-05-22 12:43:05 +0200251 int (*get_function)(struct udevice *dev, unsigned offset);
Simon Glassd3322bb2015-01-05 20:05:28 -0700252
253 /**
254 * xlate() - Translate phandle arguments into a GPIO description
255 *
256 * This function should set up the fields in desc according to the
257 * information in the arguments. The uclass will have set up:
258 *
259 * @desc->dev to @dev
260 * @desc->flags to 0
261 * @desc->offset to the value of the first argument in args, if any,
262 * otherwise -1 (which is invalid)
263 *
264 * This method is optional so if the above defaults suit it can be
265 * omitted. Typical behaviour is to set up the GPIOD_ACTIVE_LOW flag
266 * in desc->flags.
267 *
268 * Note that @dev is passed in as a parameter to follow driver model
269 * uclass conventions, even though it is already available as
270 * desc->dev.
271 *
272 * @dev: GPIO device
273 * @desc: Place to put GPIO description
274 * @args: Arguments provided in descripion
275 * @return 0 if OK, -ve on error
276 */
277 int (*xlate)(struct udevice *dev, struct gpio_desc *desc,
278 struct fdtdec_phandle_args *args);
Simon Glasse821d182014-02-26 15:59:24 -0700279};
280
281/**
282 * struct gpio_dev_priv - information about a device used by the uclass
283 *
284 * The uclass combines all active GPIO devices into a unified numbering
Marcel Ziswiler8a523c52014-10-10 17:31:41 +0200285 * scheme. To do this it maintains some private information about each
Simon Glasse821d182014-02-26 15:59:24 -0700286 * device.
287 *
288 * To implement driver model support in your GPIO driver, add a probe
289 * handler, and set @gpio_count and @bank_name correctly in that handler.
290 * This tells the uclass the name of the GPIO bank and the number of GPIOs
291 * it contains.
292 *
293 * @bank_name: Name of the GPIO device (e.g 'a' means GPIOs will be called
294 * 'A0', 'A1', etc.
295 * @gpio_count: Number of GPIOs in this device
296 * @gpio_base: Base GPIO number for this device. For the first active device
297 * this will be 0; the numbering for others will follow sequentially so that
298 * @gpio_base for device 1 will equal the number of GPIOs in device 0.
Simon Glass0f4517d2014-10-04 11:29:42 -0600299 * @name: Array of pointers to the name for each GPIO in this bank. The
300 * value of the pointer will be NULL if the GPIO has not been claimed.
Simon Glasse821d182014-02-26 15:59:24 -0700301 */
302struct gpio_dev_priv {
303 const char *bank_name;
304 unsigned gpio_count;
305 unsigned gpio_base;
Simon Glass0f4517d2014-10-04 11:29:42 -0600306 char **name;
Simon Glasse821d182014-02-26 15:59:24 -0700307};
308
309/* Access the GPIO operations for a device */
310#define gpio_get_ops(dev) ((struct dm_gpio_ops *)(dev)->driver->ops)
311
312/**
313 * gpio_get_bank_info - Return information about a GPIO bank/device
314 *
315 * This looks up a device and returns both its GPIO base name and the number
316 * of GPIOs it controls.
317 *
318 * @dev: Device to look up
319 * @offset_count: Returns number of GPIOs within this bank
320 * @return bank name of this device
321 */
Heiko Schocherb74fcb42014-05-22 12:43:05 +0200322const char *gpio_get_bank_info(struct udevice *dev, int *offset_count);
Simon Glasse821d182014-02-26 15:59:24 -0700323
324/**
325 * gpio_lookup_name - Look up a GPIO name and return its details
326 *
327 * This is used to convert a named GPIO into a device, offset and GPIO
328 * number.
329 *
330 * @name: GPIO name to look up
331 * @devp: Returns pointer to device which contains this GPIO
332 * @offsetp: Returns the offset number within this device
333 * @gpiop: Returns the absolute GPIO number, numbered from 0
334 */
Heiko Schocherb74fcb42014-05-22 12:43:05 +0200335int gpio_lookup_name(const char *name, struct udevice **devp,
Simon Glasse821d182014-02-26 15:59:24 -0700336 unsigned int *offsetp, unsigned int *gpiop);
337
Simon Glass2c97a8f2014-11-10 18:00:21 -0700338/**
Simon Glassbef54db2015-04-14 21:03:20 -0600339 * gpio_get_values_as_int() - Turn the values of a list of GPIOs into an int
Simon Glass2c97a8f2014-11-10 18:00:21 -0700340 *
341 * This puts the value of the first GPIO into bit 0, the second into bit 1,
342 * etc. then returns the resulting integer.
343 *
344 * @gpio_list: List of GPIOs to collect
Simon Glassbef54db2015-04-14 21:03:20 -0600345 * @return resulting integer value, or -ve on error
346 */
347int gpio_get_values_as_int(const int *gpio_list);
348
349/**
350 * gpio_claim_vector() - claim a number of GPIOs for input
351 *
352 * @gpio_num_array: array of gpios to claim, terminated by -1
353 * @fmt: format string for GPIO names, e.g. "board_id%d"
354 * @return 0 if OK, -ve on error
Simon Glass2c97a8f2014-11-10 18:00:21 -0700355 */
Simon Glassbef54db2015-04-14 21:03:20 -0600356int gpio_claim_vector(const int *gpio_num_array, const char *fmt);
Jeroen Hofsteeb613b102014-10-08 22:58:03 +0200357
Simon Glass16e10402015-01-05 20:05:29 -0700358/**
359 * gpio_request_by_name() - Locate and request a GPIO by name
360 *
361 * This operates by looking up the given list name in the device (device
362 * tree property) and requesting the GPIO for use. The property must exist
363 * in @dev's node.
364 *
365 * Use @flags to specify whether the GPIO should be an input or output. In
366 * principle this can also come from the device tree binding but most
367 * bindings don't provide this information. Specifically, when the GPIO uclass
368 * calls the xlate() method, it can return default flags, which are then
369 * ORed with this @flags.
370 *
371 * If we find that requesting the GPIO is not always needed we could add a
372 * new function or a new GPIOD_NO_REQUEST flag.
373 *
374 * At present driver model has no reference counting so if one device
375 * requests a GPIO which subsequently is unbound, the @desc->dev pointer
376 * will be invalid. However this will only happen if the GPIO device is
377 * unbound, not if it is removed, so this seems like a reasonable limitation
378 * for now. There is no real use case for unbinding drivers in normal
379 * operation.
380 *
381 * The device tree binding is doc/device-tree-bindings/gpio/gpio.txt in
382 * generate terms and each specific device may add additional details in
383 * a binding file in the same directory.
384 *
385 * @dev: Device requesting the GPIO
386 * @list_name: Name of GPIO list (e.g. "board-id-gpios")
387 * @index: Index number of the GPIO in that list use request (0=first)
388 * @desc: Returns GPIO description information. If there is no such
389 * GPIO, dev->dev will be NULL.
390 * @flags: Indicates the GPIO input/output settings (GPIOD_...)
391 * @return 0 if OK, -ENOENT if the GPIO does not exist, -EINVAL if there is
392 * something wrong with the list, or other -ve for another error (e.g.
393 * -EBUSY if a GPIO was already requested)
394 */
395int gpio_request_by_name(struct udevice *dev, const char *list_name,
396 int index, struct gpio_desc *desc, int flags);
397
398/**
399 * gpio_request_list_by_name() - Request a list of GPIOs
400 *
401 * Reads all the GPIOs from a list and requetss them. See
402 * gpio_request_by_name() for additional details. Lists should not be
403 * misused to hold unrelated or optional GPIOs. They should only be used
404 * for things like parallel data lines. A zero phandle terminates the list
405 * the list.
406 *
407 * This function will either succeed, and request all GPIOs in the list, or
408 * fail and request none (it will free already-requested GPIOs in case of
409 * an error part-way through).
410 *
411 * @dev: Device requesting the GPIO
412 * @list_name: Name of GPIO list (e.g. "board-id-gpios")
413 * @desc_list: Returns a list of GPIO description information
414 * @max_count: Maximum number of GPIOs to return (@desc_list must be at least
415 * this big)
416 * @flags: Indicates the GPIO input/output settings (GPIOD_...)
417 * @return number of GPIOs requested, or -ve on error
418 */
419int gpio_request_list_by_name(struct udevice *dev, const char *list_name,
420 struct gpio_desc *desc_list, int max_count,
421 int flags);
422
423/**
424 * gpio_get_list_count() - Returns the number of GPIOs in a list
425 *
426 * Counts the GPIOs in a list. See gpio_request_by_name() for additional
427 * details.
428 *
429 * @dev: Device requesting the GPIO
430 * @list_name: Name of GPIO list (e.g. "board-id-gpios")
431 * @return number of GPIOs (0 for an empty property) or -ENOENT if the list
432 * does not exist
433 */
434int gpio_get_list_count(struct udevice *dev, const char *list_name);
435
436/**
437 * gpio_request_by_name_nodev() - request GPIOs without a device
438 *
439 * This is a version of gpio_request_list_by_name() that does not use a
440 * device. Avoid it unless the caller is not yet using driver model
441 */
442int gpio_request_by_name_nodev(const void *blob, int node,
443 const char *list_name,
444 int index, struct gpio_desc *desc, int flags);
445
446/**
447 * gpio_request_list_by_name_nodev() - request GPIOs without a device
448 *
449 * This is a version of gpio_request_list_by_name() that does not use a
450 * device. Avoid it unless the caller is not yet using driver model
451 */
452int gpio_request_list_by_name_nodev(const void *blob, int node,
453 const char *list_name,
454 struct gpio_desc *desc_list, int max_count,
455 int flags);
456
457/**
458 * dm_gpio_free() - Free a single GPIO
459 *
460 * This frees a single GPIOs previously returned from gpio_request_by_name().
461 *
462 * @dev: Device which requested the GPIO
463 * @desc: GPIO to free
464 * @return 0 if OK, -ve on error
465 */
466int dm_gpio_free(struct udevice *dev, struct gpio_desc *desc);
467
468/**
469 * gpio_free_list() - Free a list of GPIOs
470 *
471 * This frees a list of GPIOs previously returned from
472 * gpio_request_list_by_name().
473 *
474 * @dev: Device which requested the GPIOs
475 * @desc: List of GPIOs to free
476 * @count: Number of GPIOs in the list
477 * @return 0 if OK, -ve on error
478 */
479int gpio_free_list(struct udevice *dev, struct gpio_desc *desc, int count);
480
481/**
482 * gpio_free_list_nodev() - free GPIOs without a device
483 *
484 * This is a version of gpio_free_list() that does not use a
485 * device. Avoid it unless the caller is not yet using driver model
486 */
487int gpio_free_list_nodev(struct gpio_desc *desc, int count);
488
489/**
490 * dm_gpio_get_value() - Get the value of a GPIO
491 *
492 * This is the driver model version of the existing gpio_get_value() function
493 * and should be used instead of that.
494 *
495 * For now, these functions have a dm_ prefix since they conflict with
496 * existing names.
497 *
498 * @desc: GPIO description containing device, offset and flags,
499 * previously returned by gpio_request_by_name()
500 * @return GPIO value (0 for inactive, 1 for active) or -ve on error
501 */
502int dm_gpio_get_value(struct gpio_desc *desc);
503
504int dm_gpio_set_value(struct gpio_desc *desc, int value);
505
506/**
507 * dm_gpio_set_dir() - Set the direction for a GPIO
508 *
509 * This sets up the direction according tot the provided flags. It will do
510 * nothing unless the direction is actually specified.
511 *
512 * @desc: GPIO description containing device, offset and flags,
513 * previously returned by gpio_request_by_name()
514 * @return 0 if OK, -ve on error
515 */
516int dm_gpio_set_dir(struct gpio_desc *desc);
517
518/**
519 * dm_gpio_set_dir_flags() - Set direction using specific flags
520 *
521 * This is like dm_gpio_set_dir() except that the flags value is provided
522 * instead of being used from desc->flags. This is needed because in many
523 * cases the GPIO description does not include direction information.
524 * Note that desc->flags is updated by this function.
525 *
526 * @desc: GPIO description containing device, offset and flags,
527 * previously returned by gpio_request_by_name()
528 * @flags: New flags to use
529 * @return 0 if OK, -ve on error, in which case desc->flags is not updated
530 */
531int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags);
532
533/**
534 * gpio_get_number() - Get the global GPIO number of a GPIO
535 *
536 * This should only be used for debugging or interest. It returns the nummber
537 * that should be used for gpio_get_value() etc. to access this GPIO.
538 *
539 * @desc: GPIO description containing device, offset and flags,
540 * previously returned by gpio_request_by_name()
541 * @return GPIO number, or -ve if not found
542 */
543int gpio_get_number(struct gpio_desc *desc);
544
Joe Hershberger334b2322011-11-11 15:55:35 -0600545#endif /* _ASM_GENERIC_GPIO_H_ */