Commit | Line | Data |
---|---|---|
d2876d08 DB |
1 | #include <linux/kernel.h> |
2 | #include <linux/module.h> | |
ff77c352 | 3 | #include <linux/interrupt.h> |
d2876d08 DB |
4 | #include <linux/irq.h> |
5 | #include <linux/spinlock.h> | |
1a989d0f | 6 | #include <linux/list.h> |
d8f388d8 DB |
7 | #include <linux/device.h> |
8 | #include <linux/err.h> | |
9 | #include <linux/debugfs.h> | |
10 | #include <linux/seq_file.h> | |
11 | #include <linux/gpio.h> | |
391c970c | 12 | #include <linux/of_gpio.h> |
ff77c352 | 13 | #include <linux/idr.h> |
5a0e3ad6 | 14 | #include <linux/slab.h> |
7b199811 | 15 | #include <linux/acpi.h> |
53e7cac3 | 16 | #include <linux/gpio/driver.h> |
0a6d3158 | 17 | #include <linux/gpio/machine.h> |
d2876d08 | 18 | |
664e3e5a MW |
19 | #include "gpiolib.h" |
20 | ||
3f397c21 UKK |
21 | #define CREATE_TRACE_POINTS |
22 | #include <trace/events/gpio.h> | |
d2876d08 | 23 | |
79a9becd | 24 | /* Implementation infrastructure for GPIO interfaces. |
d2876d08 | 25 | * |
79a9becd AC |
26 | * The GPIO programming interface allows for inlining speed-critical |
27 | * get/set operations for common cases, so that access to SOC-integrated | |
28 | * GPIOs can sometimes cost only an instruction or two per bit. | |
d2876d08 DB |
29 | */ |
30 | ||
31 | ||
32 | /* When debugging, extend minimal trust to callers and platform code. | |
33 | * Also emit diagnostic messages that may help initial bringup, when | |
34 | * board setup or driver bugs are most common. | |
35 | * | |
36 | * Otherwise, minimize overhead in what may be bitbanging codepaths. | |
37 | */ | |
38 | #ifdef DEBUG | |
39 | #define extra_checks 1 | |
40 | #else | |
41 | #define extra_checks 0 | |
42 | #endif | |
43 | ||
44 | /* gpio_lock prevents conflicts during gpio_desc[] table updates. | |
45 | * While any GPIO is requested, its gpio_chip is not removable; | |
46 | * each GPIO's "requested" flag serves as a lock and refcount. | |
47 | */ | |
0eb4c6c2 | 48 | DEFINE_SPINLOCK(gpio_lock); |
d2876d08 | 49 | |
6c0b4e6c AC |
50 | #define GPIO_OFFSET_VALID(chip, offset) (offset >= 0 && offset < chip->ngpio) |
51 | ||
bae48da2 AC |
52 | static DEFINE_MUTEX(gpio_lookup_lock); |
53 | static LIST_HEAD(gpio_lookup_list); | |
0eb4c6c2 | 54 | LIST_HEAD(gpio_chips); |
1a2a99c6 | 55 | |
6d86750c JH |
56 | |
57 | static void gpiochip_free_hogs(struct gpio_chip *chip); | |
58 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); | |
59 | ||
60 | ||
d2876d08 DB |
61 | static inline void desc_set_label(struct gpio_desc *d, const char *label) |
62 | { | |
d2876d08 | 63 | d->label = label; |
d2876d08 DB |
64 | } |
65 | ||
372e722e AC |
66 | /** |
67 | * Convert a GPIO number to its descriptor | |
68 | */ | |
79a9becd | 69 | struct gpio_desc *gpio_to_desc(unsigned gpio) |
372e722e | 70 | { |
14e85c0e AC |
71 | struct gpio_chip *chip; |
72 | unsigned long flags; | |
73 | ||
74 | spin_lock_irqsave(&gpio_lock, flags); | |
75 | ||
76 | list_for_each_entry(chip, &gpio_chips, list) { | |
77 | if (chip->base <= gpio && chip->base + chip->ngpio > gpio) { | |
78 | spin_unlock_irqrestore(&gpio_lock, flags); | |
79 | return &chip->desc[gpio - chip->base]; | |
80 | } | |
81 | } | |
82 | ||
83 | spin_unlock_irqrestore(&gpio_lock, flags); | |
84 | ||
0e9a5edf AC |
85 | if (!gpio_is_valid(gpio)) |
86 | WARN(1, "invalid GPIO %d\n", gpio); | |
87 | ||
14e85c0e | 88 | return NULL; |
372e722e | 89 | } |
79a9becd | 90 | EXPORT_SYMBOL_GPL(gpio_to_desc); |
372e722e | 91 | |
d468bf9e | 92 | /** |
bb1e88cc | 93 | * Get the GPIO descriptor corresponding to the given hw number for this chip. |
d468bf9e | 94 | */ |
bb1e88cc AC |
95 | struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, |
96 | u16 hwnum) | |
d468bf9e | 97 | { |
bb1e88cc | 98 | if (hwnum >= chip->ngpio) |
b7d0a28a | 99 | return ERR_PTR(-EINVAL); |
d468bf9e | 100 | |
bb1e88cc | 101 | return &chip->desc[hwnum]; |
d468bf9e | 102 | } |
372e722e AC |
103 | |
104 | /** | |
105 | * Convert a GPIO descriptor to the integer namespace. | |
106 | * This should disappear in the future but is needed since we still | |
107 | * use GPIO numbers for error messages and sysfs nodes | |
108 | */ | |
79a9becd | 109 | int desc_to_gpio(const struct gpio_desc *desc) |
372e722e | 110 | { |
14e85c0e | 111 | return desc->chip->base + (desc - &desc->chip->desc[0]); |
372e722e | 112 | } |
79a9becd | 113 | EXPORT_SYMBOL_GPL(desc_to_gpio); |
372e722e AC |
114 | |
115 | ||
79a9becd AC |
116 | /** |
117 | * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs | |
118 | * @desc: descriptor to return the chip of | |
119 | */ | |
120 | struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) | |
372e722e | 121 | { |
bcabdef1 | 122 | return desc ? desc->chip : NULL; |
372e722e | 123 | } |
79a9becd | 124 | EXPORT_SYMBOL_GPL(gpiod_to_chip); |
d2876d08 | 125 | |
8d0aab2f AV |
126 | /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ |
127 | static int gpiochip_find_base(int ngpio) | |
128 | { | |
83cabe33 AC |
129 | struct gpio_chip *chip; |
130 | int base = ARCH_NR_GPIOS - ngpio; | |
8d0aab2f | 131 | |
83cabe33 AC |
132 | list_for_each_entry_reverse(chip, &gpio_chips, list) { |
133 | /* found a free space? */ | |
134 | if (chip->base + chip->ngpio <= base) | |
135 | break; | |
136 | else | |
137 | /* nope, check the space right before the chip */ | |
138 | base = chip->base - ngpio; | |
8d0aab2f AV |
139 | } |
140 | ||
83cabe33 | 141 | if (gpio_is_valid(base)) { |
8d0aab2f | 142 | pr_debug("%s: found new base at %d\n", __func__, base); |
83cabe33 AC |
143 | return base; |
144 | } else { | |
145 | pr_err("%s: cannot find free range\n", __func__); | |
146 | return -ENOSPC; | |
169b6a7a | 147 | } |
169b6a7a AV |
148 | } |
149 | ||
79a9becd AC |
150 | /** |
151 | * gpiod_get_direction - return the current direction of a GPIO | |
152 | * @desc: GPIO to get the direction of | |
153 | * | |
154 | * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error. | |
155 | * | |
156 | * This function may sleep if gpiod_cansleep() is true. | |
157 | */ | |
8e53b0f1 | 158 | int gpiod_get_direction(struct gpio_desc *desc) |
80b0a602 MN |
159 | { |
160 | struct gpio_chip *chip; | |
372e722e | 161 | unsigned offset; |
80b0a602 MN |
162 | int status = -EINVAL; |
163 | ||
372e722e AC |
164 | chip = gpiod_to_chip(desc); |
165 | offset = gpio_chip_hwgpio(desc); | |
80b0a602 MN |
166 | |
167 | if (!chip->get_direction) | |
168 | return status; | |
169 | ||
372e722e | 170 | status = chip->get_direction(chip, offset); |
80b0a602 MN |
171 | if (status > 0) { |
172 | /* GPIOF_DIR_IN, or other positive */ | |
173 | status = 1; | |
8e53b0f1 | 174 | clear_bit(FLAG_IS_OUT, &desc->flags); |
80b0a602 MN |
175 | } |
176 | if (status == 0) { | |
177 | /* GPIOF_DIR_OUT */ | |
8e53b0f1 | 178 | set_bit(FLAG_IS_OUT, &desc->flags); |
80b0a602 MN |
179 | } |
180 | return status; | |
181 | } | |
79a9becd | 182 | EXPORT_SYMBOL_GPL(gpiod_get_direction); |
80b0a602 | 183 | |
1a989d0f AC |
184 | /* |
185 | * Add a new chip to the global chips list, keeping the list of chips sorted | |
186 | * by base order. | |
187 | * | |
188 | * Return -EBUSY if the new chip overlaps with some other chip's integer | |
189 | * space. | |
190 | */ | |
191 | static int gpiochip_add_to_list(struct gpio_chip *chip) | |
192 | { | |
193 | struct list_head *pos = &gpio_chips; | |
194 | struct gpio_chip *_chip; | |
195 | int err = 0; | |
196 | ||
197 | /* find where to insert our chip */ | |
198 | list_for_each(pos, &gpio_chips) { | |
199 | _chip = list_entry(pos, struct gpio_chip, list); | |
200 | /* shall we insert before _chip? */ | |
201 | if (_chip->base >= chip->base + chip->ngpio) | |
202 | break; | |
203 | } | |
204 | ||
205 | /* are we stepping on the chip right before? */ | |
206 | if (pos != &gpio_chips && pos->prev != &gpio_chips) { | |
207 | _chip = list_entry(pos->prev, struct gpio_chip, list); | |
208 | if (_chip->base + _chip->ngpio > chip->base) { | |
209 | dev_err(chip->dev, | |
210 | "GPIO integer space overlap, cannot add chip\n"); | |
211 | err = -EBUSY; | |
212 | } | |
213 | } | |
214 | ||
215 | if (!err) | |
216 | list_add_tail(&chip->list, pos); | |
217 | ||
218 | return err; | |
219 | } | |
220 | ||
d2876d08 DB |
221 | /** |
222 | * gpiochip_add() - register a gpio_chip | |
223 | * @chip: the chip to register, with chip->base initialized | |
14e85c0e | 224 | * Context: potentially before irqs will work |
d2876d08 DB |
225 | * |
226 | * Returns a negative errno if the chip can't be registered, such as | |
227 | * because the chip->base is invalid or already associated with a | |
228 | * different chip. Otherwise it returns zero as a success code. | |
8d0aab2f | 229 | * |
d8f388d8 DB |
230 | * When gpiochip_add() is called very early during boot, so that GPIOs |
231 | * can be freely used, the chip->dev device must be registered before | |
232 | * the gpio framework's arch_initcall(). Otherwise sysfs initialization | |
233 | * for GPIOs will fail rudely. | |
234 | * | |
8d0aab2f AV |
235 | * If chip->base is negative, this requests dynamic assignment of |
236 | * a range of valid GPIOs. | |
d2876d08 DB |
237 | */ |
238 | int gpiochip_add(struct gpio_chip *chip) | |
239 | { | |
240 | unsigned long flags; | |
241 | int status = 0; | |
242 | unsigned id; | |
8d0aab2f | 243 | int base = chip->base; |
14e85c0e | 244 | struct gpio_desc *descs; |
d2876d08 | 245 | |
14e85c0e AC |
246 | descs = kcalloc(chip->ngpio, sizeof(descs[0]), GFP_KERNEL); |
247 | if (!descs) | |
248 | return -ENOMEM; | |
d2876d08 DB |
249 | |
250 | spin_lock_irqsave(&gpio_lock, flags); | |
251 | ||
8d0aab2f AV |
252 | if (base < 0) { |
253 | base = gpiochip_find_base(chip->ngpio); | |
254 | if (base < 0) { | |
255 | status = base; | |
225fce83 JH |
256 | spin_unlock_irqrestore(&gpio_lock, flags); |
257 | goto err_free_descs; | |
8d0aab2f AV |
258 | } |
259 | chip->base = base; | |
260 | } | |
261 | ||
1a989d0f | 262 | status = gpiochip_add_to_list(chip); |
05aa5203 JH |
263 | if (status) { |
264 | spin_unlock_irqrestore(&gpio_lock, flags); | |
265 | goto err_free_descs; | |
266 | } | |
1a989d0f | 267 | |
05aa5203 JH |
268 | for (id = 0; id < chip->ngpio; id++) { |
269 | struct gpio_desc *desc = &descs[id]; | |
270 | ||
271 | desc->chip = chip; | |
272 | ||
273 | /* REVISIT: most hardware initializes GPIOs as inputs (often | |
274 | * with pullups enabled) so power usage is minimized. Linux | |
275 | * code should set the gpio direction first thing; but until | |
276 | * it does, and in case chip->get_direction is not set, we may | |
277 | * expose the wrong direction in sysfs. | |
278 | */ | |
279 | desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0; | |
d2876d08 DB |
280 | } |
281 | ||
14e85c0e AC |
282 | chip->desc = descs; |
283 | ||
3bae4811 ZG |
284 | spin_unlock_irqrestore(&gpio_lock, flags); |
285 | ||
f23f1516 SH |
286 | #ifdef CONFIG_PINCTRL |
287 | INIT_LIST_HEAD(&chip->pin_ranges); | |
288 | #endif | |
289 | ||
3726960e GS |
290 | if (!chip->owner && chip->dev && chip->dev->driver) |
291 | chip->owner = chip->dev->driver->owner; | |
292 | ||
391c970c | 293 | of_gpiochip_add(chip); |
664e3e5a | 294 | acpi_gpiochip_add(chip); |
391c970c | 295 | |
426577bd | 296 | status = gpiochip_sysfs_register(chip); |
225fce83 JH |
297 | if (status) |
298 | goto err_remove_chip; | |
cedb1881 | 299 | |
7589e59f | 300 | pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__, |
64842aad GL |
301 | chip->base, chip->base + chip->ngpio - 1, |
302 | chip->label ? : "generic"); | |
303 | ||
cedb1881 | 304 | return 0; |
3bae4811 | 305 | |
225fce83 JH |
306 | err_remove_chip: |
307 | acpi_gpiochip_remove(chip); | |
6d86750c | 308 | gpiochip_free_hogs(chip); |
225fce83 JH |
309 | of_gpiochip_remove(chip); |
310 | spin_lock_irqsave(&gpio_lock, flags); | |
311 | list_del(&chip->list); | |
3bae4811 | 312 | spin_unlock_irqrestore(&gpio_lock, flags); |
05aa5203 | 313 | chip->desc = NULL; |
225fce83 | 314 | err_free_descs: |
14e85c0e | 315 | kfree(descs); |
14e85c0e | 316 | |
d2876d08 | 317 | /* failures here can mean systems won't boot... */ |
7589e59f | 318 | pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__, |
cedb1881 AV |
319 | chip->base, chip->base + chip->ngpio - 1, |
320 | chip->label ? : "generic"); | |
d2876d08 DB |
321 | return status; |
322 | } | |
323 | EXPORT_SYMBOL_GPL(gpiochip_add); | |
324 | ||
325 | /** | |
326 | * gpiochip_remove() - unregister a gpio_chip | |
327 | * @chip: the chip to unregister | |
328 | * | |
329 | * A gpio_chip with any GPIOs still requested may not be removed. | |
330 | */ | |
e1db1706 | 331 | void gpiochip_remove(struct gpio_chip *chip) |
d2876d08 | 332 | { |
fab28b89 | 333 | struct gpio_desc *desc; |
d2876d08 | 334 | unsigned long flags; |
d2876d08 | 335 | unsigned id; |
fab28b89 | 336 | bool requested = false; |
d2876d08 | 337 | |
426577bd | 338 | gpiochip_sysfs_unregister(chip); |
01cca93a | 339 | |
00acc3dc JH |
340 | gpiochip_irqchip_remove(chip); |
341 | ||
6072b9dc | 342 | acpi_gpiochip_remove(chip); |
9ef0d6f7 | 343 | gpiochip_remove_pin_ranges(chip); |
f625d460 | 344 | gpiochip_free_hogs(chip); |
391c970c AV |
345 | of_gpiochip_remove(chip); |
346 | ||
6798acaa | 347 | spin_lock_irqsave(&gpio_lock, flags); |
6c0b4e6c | 348 | for (id = 0; id < chip->ngpio; id++) { |
fab28b89 JH |
349 | desc = &chip->desc[id]; |
350 | desc->chip = NULL; | |
351 | if (test_bit(FLAG_REQUESTED, &desc->flags)) | |
352 | requested = true; | |
d2876d08 | 353 | } |
e1db1706 | 354 | list_del(&chip->list); |
d2876d08 | 355 | spin_unlock_irqrestore(&gpio_lock, flags); |
14e85c0e | 356 | |
fab28b89 JH |
357 | if (requested) |
358 | dev_crit(chip->dev, "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n"); | |
359 | ||
14e85c0e AC |
360 | kfree(chip->desc); |
361 | chip->desc = NULL; | |
d2876d08 DB |
362 | } |
363 | EXPORT_SYMBOL_GPL(gpiochip_remove); | |
364 | ||
594fa265 GL |
365 | /** |
366 | * gpiochip_find() - iterator for locating a specific gpio_chip | |
367 | * @data: data to pass to match function | |
368 | * @callback: Callback function to check gpio_chip | |
369 | * | |
370 | * Similar to bus_find_device. It returns a reference to a gpio_chip as | |
371 | * determined by a user supplied @match callback. The callback should return | |
372 | * 0 if the device doesn't match and non-zero if it does. If the callback is | |
373 | * non-zero, this function will return to the caller and not iterate over any | |
374 | * more gpio_chips. | |
375 | */ | |
07ce8ec7 | 376 | struct gpio_chip *gpiochip_find(void *data, |
6e2cf651 | 377 | int (*match)(struct gpio_chip *chip, |
3d0f7cf0 | 378 | void *data)) |
594fa265 | 379 | { |
125eef96 | 380 | struct gpio_chip *chip; |
594fa265 | 381 | unsigned long flags; |
594fa265 GL |
382 | |
383 | spin_lock_irqsave(&gpio_lock, flags); | |
125eef96 AC |
384 | list_for_each_entry(chip, &gpio_chips, list) |
385 | if (match(chip, data)) | |
594fa265 | 386 | break; |
125eef96 AC |
387 | |
388 | /* No match? */ | |
389 | if (&chip->list == &gpio_chips) | |
390 | chip = NULL; | |
594fa265 GL |
391 | spin_unlock_irqrestore(&gpio_lock, flags); |
392 | ||
393 | return chip; | |
394 | } | |
8fa0c9bf | 395 | EXPORT_SYMBOL_GPL(gpiochip_find); |
d2876d08 | 396 | |
79697ef9 AC |
397 | static int gpiochip_match_name(struct gpio_chip *chip, void *data) |
398 | { | |
399 | const char *name = data; | |
400 | ||
401 | return !strcmp(chip->label, name); | |
402 | } | |
403 | ||
404 | static struct gpio_chip *find_chip_by_name(const char *name) | |
405 | { | |
406 | return gpiochip_find((void *)name, gpiochip_match_name); | |
407 | } | |
408 | ||
14250520 LW |
409 | #ifdef CONFIG_GPIOLIB_IRQCHIP |
410 | ||
411 | /* | |
412 | * The following is irqchip helper code for gpiochips. | |
413 | */ | |
414 | ||
415 | /** | |
3f97d5fc LW |
416 | * gpiochip_set_chained_irqchip() - sets a chained irqchip to a gpiochip |
417 | * @gpiochip: the gpiochip to set the irqchip chain to | |
418 | * @irqchip: the irqchip to chain to the gpiochip | |
14250520 LW |
419 | * @parent_irq: the irq number corresponding to the parent IRQ for this |
420 | * chained irqchip | |
421 | * @parent_handler: the parent interrupt handler for the accumulated IRQ | |
3f97d5fc LW |
422 | * coming out of the gpiochip. If the interrupt is nested rather than |
423 | * cascaded, pass NULL in this handler argument | |
14250520 LW |
424 | */ |
425 | void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, | |
426 | struct irq_chip *irqchip, | |
427 | int parent_irq, | |
428 | irq_flow_handler_t parent_handler) | |
429 | { | |
83141a77 LW |
430 | unsigned int offset; |
431 | ||
83141a77 LW |
432 | if (!gpiochip->irqdomain) { |
433 | chip_err(gpiochip, "called %s before setting up irqchip\n", | |
434 | __func__); | |
1c8732bb LW |
435 | return; |
436 | } | |
437 | ||
3f97d5fc LW |
438 | if (parent_handler) { |
439 | if (gpiochip->can_sleep) { | |
440 | chip_err(gpiochip, | |
441 | "you cannot have chained interrupts on a " | |
442 | "chip that may sleep\n"); | |
443 | return; | |
444 | } | |
3f97d5fc LW |
445 | /* |
446 | * The parent irqchip is already using the chip_data for this | |
447 | * irqchip, so our callbacks simply use the handler_data. | |
448 | */ | |
f7f87753 TG |
449 | irq_set_chained_handler_and_data(parent_irq, parent_handler, |
450 | gpiochip); | |
25e4fe92 DES |
451 | |
452 | gpiochip->irq_parent = parent_irq; | |
3f97d5fc | 453 | } |
83141a77 LW |
454 | |
455 | /* Set the parent IRQ for all affected IRQs */ | |
456 | for (offset = 0; offset < gpiochip->ngpio; offset++) | |
457 | irq_set_parent(irq_find_mapping(gpiochip->irqdomain, offset), | |
458 | parent_irq); | |
14250520 LW |
459 | } |
460 | EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip); | |
461 | ||
e45d1c80 LW |
462 | /* |
463 | * This lock class tells lockdep that GPIO irqs are in a different | |
464 | * category than their parents, so it won't report false recursion. | |
465 | */ | |
466 | static struct lock_class_key gpiochip_irq_lock_class; | |
467 | ||
14250520 LW |
468 | /** |
469 | * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip | |
470 | * @d: the irqdomain used by this irqchip | |
471 | * @irq: the global irq number used by this GPIO irqchip irq | |
472 | * @hwirq: the local IRQ/GPIO line offset on this gpiochip | |
473 | * | |
474 | * This function will set up the mapping for a certain IRQ line on a | |
475 | * gpiochip by assigning the gpiochip as chip data, and using the irqchip | |
476 | * stored inside the gpiochip. | |
477 | */ | |
478 | static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, | |
479 | irq_hw_number_t hwirq) | |
480 | { | |
481 | struct gpio_chip *chip = d->host_data; | |
482 | ||
14250520 | 483 | irq_set_chip_data(irq, chip); |
e45d1c80 | 484 | irq_set_lockdep_class(irq, &gpiochip_irq_lock_class); |
7633fb95 | 485 | irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler); |
1c8732bb | 486 | /* Chips that can sleep need nested thread handlers */ |
295494af | 487 | if (chip->can_sleep && !chip->irq_not_threaded) |
1c8732bb | 488 | irq_set_nested_thread(irq, 1); |
14250520 LW |
489 | #ifdef CONFIG_ARM |
490 | set_irq_flags(irq, IRQF_VALID); | |
491 | #else | |
492 | irq_set_noprobe(irq); | |
493 | #endif | |
1333b90f LW |
494 | /* |
495 | * No set-up of the hardware will happen if IRQ_TYPE_NONE | |
496 | * is passed as default type. | |
497 | */ | |
498 | if (chip->irq_default_type != IRQ_TYPE_NONE) | |
499 | irq_set_irq_type(irq, chip->irq_default_type); | |
14250520 LW |
500 | |
501 | return 0; | |
502 | } | |
503 | ||
c3626fde LW |
504 | static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) |
505 | { | |
1c8732bb LW |
506 | struct gpio_chip *chip = d->host_data; |
507 | ||
c3626fde LW |
508 | #ifdef CONFIG_ARM |
509 | set_irq_flags(irq, 0); | |
510 | #endif | |
1c8732bb LW |
511 | if (chip->can_sleep) |
512 | irq_set_nested_thread(irq, 0); | |
c3626fde LW |
513 | irq_set_chip_and_handler(irq, NULL, NULL); |
514 | irq_set_chip_data(irq, NULL); | |
515 | } | |
516 | ||
14250520 LW |
517 | static const struct irq_domain_ops gpiochip_domain_ops = { |
518 | .map = gpiochip_irq_map, | |
c3626fde | 519 | .unmap = gpiochip_irq_unmap, |
14250520 LW |
520 | /* Virtually all GPIO irqchips are twocell:ed */ |
521 | .xlate = irq_domain_xlate_twocell, | |
522 | }; | |
523 | ||
524 | static int gpiochip_irq_reqres(struct irq_data *d) | |
525 | { | |
526 | struct gpio_chip *chip = irq_data_get_irq_chip_data(d); | |
527 | ||
5b76e79c GS |
528 | if (!try_module_get(chip->owner)) |
529 | return -ENODEV; | |
530 | ||
e3a2e878 | 531 | if (gpiochip_lock_as_irq(chip, d->hwirq)) { |
14250520 LW |
532 | chip_err(chip, |
533 | "unable to lock HW IRQ %lu for IRQ\n", | |
534 | d->hwirq); | |
5b76e79c | 535 | module_put(chip->owner); |
14250520 LW |
536 | return -EINVAL; |
537 | } | |
538 | return 0; | |
539 | } | |
540 | ||
541 | static void gpiochip_irq_relres(struct irq_data *d) | |
542 | { | |
543 | struct gpio_chip *chip = irq_data_get_irq_chip_data(d); | |
544 | ||
e3a2e878 | 545 | gpiochip_unlock_as_irq(chip, d->hwirq); |
5b76e79c | 546 | module_put(chip->owner); |
14250520 LW |
547 | } |
548 | ||
549 | static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) | |
550 | { | |
551 | return irq_find_mapping(chip->irqdomain, offset); | |
552 | } | |
553 | ||
554 | /** | |
555 | * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip | |
556 | * @gpiochip: the gpiochip to remove the irqchip from | |
557 | * | |
558 | * This is called only from gpiochip_remove() | |
559 | */ | |
560 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) | |
561 | { | |
c3626fde LW |
562 | unsigned int offset; |
563 | ||
afa82fab MW |
564 | acpi_gpiochip_free_interrupts(gpiochip); |
565 | ||
25e4fe92 DES |
566 | if (gpiochip->irq_parent) { |
567 | irq_set_chained_handler(gpiochip->irq_parent, NULL); | |
568 | irq_set_handler_data(gpiochip->irq_parent, NULL); | |
569 | } | |
570 | ||
c3626fde LW |
571 | /* Remove all IRQ mappings and delete the domain */ |
572 | if (gpiochip->irqdomain) { | |
573 | for (offset = 0; offset < gpiochip->ngpio; offset++) | |
e3893386 GS |
574 | irq_dispose_mapping( |
575 | irq_find_mapping(gpiochip->irqdomain, offset)); | |
14250520 | 576 | irq_domain_remove(gpiochip->irqdomain); |
c3626fde | 577 | } |
14250520 LW |
578 | |
579 | if (gpiochip->irqchip) { | |
580 | gpiochip->irqchip->irq_request_resources = NULL; | |
581 | gpiochip->irqchip->irq_release_resources = NULL; | |
582 | gpiochip->irqchip = NULL; | |
583 | } | |
584 | } | |
585 | ||
586 | /** | |
587 | * gpiochip_irqchip_add() - adds an irqchip to a gpiochip | |
588 | * @gpiochip: the gpiochip to add the irqchip to | |
589 | * @irqchip: the irqchip to add to the gpiochip | |
590 | * @first_irq: if not dynamically assigned, the base (first) IRQ to | |
591 | * allocate gpiochip irqs from | |
592 | * @handler: the irq handler to use (often a predefined irq core function) | |
1333b90f LW |
593 | * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE |
594 | * to have the core avoid setting up any default type in the hardware. | |
14250520 LW |
595 | * |
596 | * This function closely associates a certain irqchip with a certain | |
597 | * gpiochip, providing an irq domain to translate the local IRQs to | |
598 | * global irqs in the gpiolib core, and making sure that the gpiochip | |
599 | * is passed as chip data to all related functions. Driver callbacks | |
600 | * need to use container_of() to get their local state containers back | |
601 | * from the gpiochip passed as chip data. An irqdomain will be stored | |
602 | * in the gpiochip that shall be used by the driver to handle IRQ number | |
603 | * translation. The gpiochip will need to be initialized and registered | |
604 | * before calling this function. | |
605 | * | |
c3626fde LW |
606 | * This function will handle two cell:ed simple IRQs and assumes all |
607 | * the pins on the gpiochip can generate a unique IRQ. Everything else | |
14250520 LW |
608 | * need to be open coded. |
609 | */ | |
610 | int gpiochip_irqchip_add(struct gpio_chip *gpiochip, | |
611 | struct irq_chip *irqchip, | |
612 | unsigned int first_irq, | |
613 | irq_flow_handler_t handler, | |
614 | unsigned int type) | |
615 | { | |
616 | struct device_node *of_node; | |
617 | unsigned int offset; | |
c3626fde | 618 | unsigned irq_base = 0; |
14250520 LW |
619 | |
620 | if (!gpiochip || !irqchip) | |
621 | return -EINVAL; | |
622 | ||
623 | if (!gpiochip->dev) { | |
624 | pr_err("missing gpiochip .dev parent pointer\n"); | |
625 | return -EINVAL; | |
626 | } | |
627 | of_node = gpiochip->dev->of_node; | |
628 | #ifdef CONFIG_OF_GPIO | |
629 | /* | |
20a8a968 | 630 | * If the gpiochip has an assigned OF node this takes precedence |
14250520 LW |
631 | * FIXME: get rid of this and use gpiochip->dev->of_node everywhere |
632 | */ | |
633 | if (gpiochip->of_node) | |
634 | of_node = gpiochip->of_node; | |
635 | #endif | |
636 | gpiochip->irqchip = irqchip; | |
637 | gpiochip->irq_handler = handler; | |
638 | gpiochip->irq_default_type = type; | |
639 | gpiochip->to_irq = gpiochip_to_irq; | |
640 | gpiochip->irqdomain = irq_domain_add_simple(of_node, | |
641 | gpiochip->ngpio, first_irq, | |
642 | &gpiochip_domain_ops, gpiochip); | |
643 | if (!gpiochip->irqdomain) { | |
644 | gpiochip->irqchip = NULL; | |
645 | return -EINVAL; | |
646 | } | |
647 | irqchip->irq_request_resources = gpiochip_irq_reqres; | |
648 | irqchip->irq_release_resources = gpiochip_irq_relres; | |
649 | ||
650 | /* | |
651 | * Prepare the mapping since the irqchip shall be orthogonal to | |
652 | * any gpiochip calls. If the first_irq was zero, this is | |
653 | * necessary to allocate descriptors for all IRQs. | |
654 | */ | |
c3626fde LW |
655 | for (offset = 0; offset < gpiochip->ngpio; offset++) { |
656 | irq_base = irq_create_mapping(gpiochip->irqdomain, offset); | |
657 | if (offset == 0) | |
658 | /* | |
659 | * Store the base into the gpiochip to be used when | |
660 | * unmapping the irqs. | |
661 | */ | |
662 | gpiochip->irq_base = irq_base; | |
663 | } | |
14250520 | 664 | |
afa82fab MW |
665 | acpi_gpiochip_request_interrupts(gpiochip); |
666 | ||
14250520 LW |
667 | return 0; |
668 | } | |
669 | EXPORT_SYMBOL_GPL(gpiochip_irqchip_add); | |
670 | ||
671 | #else /* CONFIG_GPIOLIB_IRQCHIP */ | |
672 | ||
673 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {} | |
674 | ||
675 | #endif /* CONFIG_GPIOLIB_IRQCHIP */ | |
676 | ||
f23f1516 | 677 | #ifdef CONFIG_PINCTRL |
165adc9c | 678 | |
586a87e6 CR |
679 | /** |
680 | * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping | |
681 | * @chip: the gpiochip to add the range for | |
d32651f6 | 682 | * @pctldev: the pin controller to map to |
586a87e6 CR |
683 | * @gpio_offset: the start offset in the current gpio_chip number space |
684 | * @pin_group: name of the pin group inside the pin controller | |
685 | */ | |
686 | int gpiochip_add_pingroup_range(struct gpio_chip *chip, | |
687 | struct pinctrl_dev *pctldev, | |
688 | unsigned int gpio_offset, const char *pin_group) | |
689 | { | |
690 | struct gpio_pin_range *pin_range; | |
691 | int ret; | |
692 | ||
693 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); | |
694 | if (!pin_range) { | |
1a2a99c6 | 695 | chip_err(chip, "failed to allocate pin ranges\n"); |
586a87e6 CR |
696 | return -ENOMEM; |
697 | } | |
698 | ||
699 | /* Use local offset as range ID */ | |
700 | pin_range->range.id = gpio_offset; | |
701 | pin_range->range.gc = chip; | |
702 | pin_range->range.name = chip->label; | |
703 | pin_range->range.base = chip->base + gpio_offset; | |
704 | pin_range->pctldev = pctldev; | |
705 | ||
706 | ret = pinctrl_get_group_pins(pctldev, pin_group, | |
707 | &pin_range->range.pins, | |
708 | &pin_range->range.npins); | |
61c6375d MN |
709 | if (ret < 0) { |
710 | kfree(pin_range); | |
586a87e6 | 711 | return ret; |
61c6375d | 712 | } |
586a87e6 CR |
713 | |
714 | pinctrl_add_gpio_range(pctldev, &pin_range->range); | |
715 | ||
1a2a99c6 AS |
716 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n", |
717 | gpio_offset, gpio_offset + pin_range->range.npins - 1, | |
586a87e6 CR |
718 | pinctrl_dev_get_devname(pctldev), pin_group); |
719 | ||
720 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
721 | ||
722 | return 0; | |
723 | } | |
724 | EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); | |
725 | ||
3f0f8670 LW |
726 | /** |
727 | * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping | |
728 | * @chip: the gpiochip to add the range for | |
729 | * @pinctrl_name: the dev_name() of the pin controller to map to | |
316511c0 LW |
730 | * @gpio_offset: the start offset in the current gpio_chip number space |
731 | * @pin_offset: the start offset in the pin controller number space | |
3f0f8670 LW |
732 | * @npins: the number of pins from the offset of each pin space (GPIO and |
733 | * pin controller) to accumulate in this range | |
734 | */ | |
1e63d7b9 | 735 | int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, |
316511c0 | 736 | unsigned int gpio_offset, unsigned int pin_offset, |
3f0f8670 | 737 | unsigned int npins) |
f23f1516 SH |
738 | { |
739 | struct gpio_pin_range *pin_range; | |
b4d4b1f0 | 740 | int ret; |
f23f1516 | 741 | |
3f0f8670 | 742 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); |
f23f1516 | 743 | if (!pin_range) { |
1a2a99c6 | 744 | chip_err(chip, "failed to allocate pin ranges\n"); |
1e63d7b9 | 745 | return -ENOMEM; |
f23f1516 SH |
746 | } |
747 | ||
3f0f8670 | 748 | /* Use local offset as range ID */ |
316511c0 | 749 | pin_range->range.id = gpio_offset; |
3f0f8670 | 750 | pin_range->range.gc = chip; |
f23f1516 | 751 | pin_range->range.name = chip->label; |
316511c0 LW |
752 | pin_range->range.base = chip->base + gpio_offset; |
753 | pin_range->range.pin_base = pin_offset; | |
f23f1516 | 754 | pin_range->range.npins = npins; |
192c369c | 755 | pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, |
f23f1516 | 756 | &pin_range->range); |
8f23ca1a | 757 | if (IS_ERR(pin_range->pctldev)) { |
b4d4b1f0 | 758 | ret = PTR_ERR(pin_range->pctldev); |
1a2a99c6 | 759 | chip_err(chip, "could not create pin range\n"); |
3f0f8670 | 760 | kfree(pin_range); |
b4d4b1f0 | 761 | return ret; |
3f0f8670 | 762 | } |
1a2a99c6 AS |
763 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n", |
764 | gpio_offset, gpio_offset + npins - 1, | |
316511c0 LW |
765 | pinctl_name, |
766 | pin_offset, pin_offset + npins - 1); | |
f23f1516 SH |
767 | |
768 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
1e63d7b9 LW |
769 | |
770 | return 0; | |
f23f1516 | 771 | } |
165adc9c | 772 | EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); |
f23f1516 | 773 | |
3f0f8670 LW |
774 | /** |
775 | * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings | |
776 | * @chip: the chip to remove all the mappings for | |
777 | */ | |
f23f1516 SH |
778 | void gpiochip_remove_pin_ranges(struct gpio_chip *chip) |
779 | { | |
780 | struct gpio_pin_range *pin_range, *tmp; | |
781 | ||
782 | list_for_each_entry_safe(pin_range, tmp, &chip->pin_ranges, node) { | |
783 | list_del(&pin_range->node); | |
784 | pinctrl_remove_gpio_range(pin_range->pctldev, | |
785 | &pin_range->range); | |
3f0f8670 | 786 | kfree(pin_range); |
f23f1516 SH |
787 | } |
788 | } | |
165adc9c LW |
789 | EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); |
790 | ||
791 | #endif /* CONFIG_PINCTRL */ | |
f23f1516 | 792 | |
d2876d08 DB |
793 | /* These "optional" allocation calls help prevent drivers from stomping |
794 | * on each other, and help provide better diagnostics in debugfs. | |
795 | * They're called even less than the "set direction" calls. | |
796 | */ | |
77c2d792 | 797 | static int __gpiod_request(struct gpio_desc *desc, const char *label) |
d2876d08 | 798 | { |
77c2d792 MW |
799 | struct gpio_chip *chip = desc->chip; |
800 | int status; | |
d2876d08 DB |
801 | unsigned long flags; |
802 | ||
bcabdef1 AC |
803 | spin_lock_irqsave(&gpio_lock, flags); |
804 | ||
d2876d08 | 805 | /* NOTE: gpio_request() can be called in early boot, |
35e8bb51 | 806 | * before IRQs are enabled, for non-sleeping (SOC) GPIOs. |
d2876d08 DB |
807 | */ |
808 | ||
809 | if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { | |
810 | desc_set_label(desc, label ? : "?"); | |
811 | status = 0; | |
438d8908 | 812 | } else { |
d2876d08 | 813 | status = -EBUSY; |
7460db56 | 814 | goto done; |
35e8bb51 DB |
815 | } |
816 | ||
817 | if (chip->request) { | |
818 | /* chip->request may sleep */ | |
819 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 820 | status = chip->request(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
821 | spin_lock_irqsave(&gpio_lock, flags); |
822 | ||
823 | if (status < 0) { | |
824 | desc_set_label(desc, NULL); | |
35e8bb51 | 825 | clear_bit(FLAG_REQUESTED, &desc->flags); |
80b0a602 | 826 | goto done; |
35e8bb51 | 827 | } |
438d8908 | 828 | } |
80b0a602 MN |
829 | if (chip->get_direction) { |
830 | /* chip->get_direction may sleep */ | |
831 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 832 | gpiod_get_direction(desc); |
80b0a602 MN |
833 | spin_lock_irqsave(&gpio_lock, flags); |
834 | } | |
77c2d792 MW |
835 | done: |
836 | spin_unlock_irqrestore(&gpio_lock, flags); | |
837 | return status; | |
838 | } | |
839 | ||
0eb4c6c2 | 840 | int gpiod_request(struct gpio_desc *desc, const char *label) |
77c2d792 MW |
841 | { |
842 | int status = -EPROBE_DEFER; | |
843 | struct gpio_chip *chip; | |
844 | ||
845 | if (!desc) { | |
846 | pr_warn("%s: invalid GPIO\n", __func__); | |
847 | return -EINVAL; | |
848 | } | |
849 | ||
850 | chip = desc->chip; | |
851 | if (!chip) | |
852 | goto done; | |
853 | ||
854 | if (try_module_get(chip->owner)) { | |
855 | status = __gpiod_request(desc, label); | |
856 | if (status < 0) | |
857 | module_put(chip->owner); | |
858 | } | |
859 | ||
d2876d08 DB |
860 | done: |
861 | if (status) | |
7589e59f | 862 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
77c2d792 | 863 | |
d2876d08 DB |
864 | return status; |
865 | } | |
372e722e | 866 | |
77c2d792 | 867 | static bool __gpiod_free(struct gpio_desc *desc) |
d2876d08 | 868 | { |
77c2d792 | 869 | bool ret = false; |
d2876d08 | 870 | unsigned long flags; |
35e8bb51 | 871 | struct gpio_chip *chip; |
d2876d08 | 872 | |
3d599d1c UKK |
873 | might_sleep(); |
874 | ||
372e722e | 875 | gpiod_unexport(desc); |
d8f388d8 | 876 | |
d2876d08 DB |
877 | spin_lock_irqsave(&gpio_lock, flags); |
878 | ||
35e8bb51 DB |
879 | chip = desc->chip; |
880 | if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { | |
881 | if (chip->free) { | |
882 | spin_unlock_irqrestore(&gpio_lock, flags); | |
9c4ba946 | 883 | might_sleep_if(chip->can_sleep); |
372e722e | 884 | chip->free(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
885 | spin_lock_irqsave(&gpio_lock, flags); |
886 | } | |
d2876d08 | 887 | desc_set_label(desc, NULL); |
07697461 | 888 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); |
35e8bb51 | 889 | clear_bit(FLAG_REQUESTED, &desc->flags); |
aca5ce14 | 890 | clear_bit(FLAG_OPEN_DRAIN, &desc->flags); |
25553ff0 | 891 | clear_bit(FLAG_OPEN_SOURCE, &desc->flags); |
f625d460 | 892 | clear_bit(FLAG_IS_HOGGED, &desc->flags); |
77c2d792 MW |
893 | ret = true; |
894 | } | |
d2876d08 DB |
895 | |
896 | spin_unlock_irqrestore(&gpio_lock, flags); | |
77c2d792 MW |
897 | return ret; |
898 | } | |
899 | ||
0eb4c6c2 | 900 | void gpiod_free(struct gpio_desc *desc) |
77c2d792 MW |
901 | { |
902 | if (desc && __gpiod_free(desc)) | |
903 | module_put(desc->chip->owner); | |
904 | else | |
905 | WARN_ON(extra_checks); | |
d2876d08 | 906 | } |
372e722e | 907 | |
d2876d08 DB |
908 | /** |
909 | * gpiochip_is_requested - return string iff signal was requested | |
910 | * @chip: controller managing the signal | |
911 | * @offset: of signal within controller's 0..(ngpio - 1) range | |
912 | * | |
913 | * Returns NULL if the GPIO is not currently requested, else a string. | |
9c8318ff AC |
914 | * The string returned is the label passed to gpio_request(); if none has been |
915 | * passed it is a meaningless, non-NULL constant. | |
d2876d08 DB |
916 | * |
917 | * This function is for use by GPIO controller drivers. The label can | |
918 | * help with diagnostics, and knowing that the signal is used as a GPIO | |
919 | * can help avoid accidentally multiplexing it to another controller. | |
920 | */ | |
921 | const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) | |
922 | { | |
6c0b4e6c | 923 | struct gpio_desc *desc; |
d2876d08 | 924 | |
6c0b4e6c | 925 | if (!GPIO_OFFSET_VALID(chip, offset)) |
d2876d08 | 926 | return NULL; |
6c0b4e6c AC |
927 | |
928 | desc = &chip->desc[offset]; | |
929 | ||
372e722e | 930 | if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) |
d2876d08 | 931 | return NULL; |
372e722e | 932 | return desc->label; |
d2876d08 DB |
933 | } |
934 | EXPORT_SYMBOL_GPL(gpiochip_is_requested); | |
935 | ||
77c2d792 MW |
936 | /** |
937 | * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor | |
938 | * @desc: GPIO descriptor to request | |
939 | * @label: label for the GPIO | |
940 | * | |
941 | * Function allows GPIO chip drivers to request and use their own GPIO | |
942 | * descriptors via gpiolib API. Difference to gpiod_request() is that this | |
943 | * function will not increase reference count of the GPIO chip module. This | |
944 | * allows the GPIO chip module to be unloaded as needed (we assume that the | |
945 | * GPIO chip driver handles freeing the GPIOs it has requested). | |
946 | */ | |
abdc08a3 AC |
947 | struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum, |
948 | const char *label) | |
77c2d792 | 949 | { |
abdc08a3 AC |
950 | struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum); |
951 | int err; | |
77c2d792 | 952 | |
abdc08a3 AC |
953 | if (IS_ERR(desc)) { |
954 | chip_err(chip, "failed to get GPIO descriptor\n"); | |
955 | return desc; | |
956 | } | |
957 | ||
958 | err = __gpiod_request(desc, label); | |
959 | if (err < 0) | |
960 | return ERR_PTR(err); | |
77c2d792 | 961 | |
abdc08a3 | 962 | return desc; |
77c2d792 | 963 | } |
f7d4ad98 | 964 | EXPORT_SYMBOL_GPL(gpiochip_request_own_desc); |
77c2d792 MW |
965 | |
966 | /** | |
967 | * gpiochip_free_own_desc - Free GPIO requested by the chip driver | |
968 | * @desc: GPIO descriptor to free | |
969 | * | |
970 | * Function frees the given GPIO requested previously with | |
971 | * gpiochip_request_own_desc(). | |
972 | */ | |
973 | void gpiochip_free_own_desc(struct gpio_desc *desc) | |
974 | { | |
975 | if (desc) | |
976 | __gpiod_free(desc); | |
977 | } | |
f7d4ad98 | 978 | EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); |
d2876d08 DB |
979 | |
980 | /* Drivers MUST set GPIO direction before making get/set calls. In | |
981 | * some cases this is done in early boot, before IRQs are enabled. | |
982 | * | |
983 | * As a rule these aren't called more than once (except for drivers | |
984 | * using the open-drain emulation idiom) so these are natural places | |
985 | * to accumulate extra debugging checks. Note that we can't (yet) | |
986 | * rely on gpio_request() having been called beforehand. | |
987 | */ | |
988 | ||
79a9becd AC |
989 | /** |
990 | * gpiod_direction_input - set the GPIO direction to input | |
991 | * @desc: GPIO to set to input | |
992 | * | |
993 | * Set the direction of the passed GPIO to input, such as gpiod_get_value() can | |
994 | * be called safely on it. | |
995 | * | |
996 | * Return 0 in case of success, else an error code. | |
997 | */ | |
998 | int gpiod_direction_input(struct gpio_desc *desc) | |
d2876d08 | 999 | { |
d2876d08 | 1000 | struct gpio_chip *chip; |
d2876d08 DB |
1001 | int status = -EINVAL; |
1002 | ||
be1a4b13 | 1003 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1004 | pr_warn("%s: invalid GPIO\n", __func__); |
1005 | return -EINVAL; | |
1006 | } | |
1007 | ||
be1a4b13 LW |
1008 | chip = desc->chip; |
1009 | if (!chip->get || !chip->direction_input) { | |
6424de5a MB |
1010 | gpiod_warn(desc, |
1011 | "%s: missing get() or direction_input() operations\n", | |
7589e59f | 1012 | __func__); |
be1a4b13 LW |
1013 | return -EIO; |
1014 | } | |
1015 | ||
d82da797 | 1016 | status = chip->direction_input(chip, gpio_chip_hwgpio(desc)); |
d2876d08 DB |
1017 | if (status == 0) |
1018 | clear_bit(FLAG_IS_OUT, &desc->flags); | |
3f397c21 | 1019 | |
372e722e | 1020 | trace_gpio_direction(desc_to_gpio(desc), 1, status); |
d82da797 | 1021 | |
d2876d08 DB |
1022 | return status; |
1023 | } | |
79a9becd | 1024 | EXPORT_SYMBOL_GPL(gpiod_direction_input); |
372e722e | 1025 | |
ef70bbe1 | 1026 | static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) |
d2876d08 | 1027 | { |
d2876d08 | 1028 | struct gpio_chip *chip; |
d2876d08 DB |
1029 | int status = -EINVAL; |
1030 | ||
d468bf9e LW |
1031 | /* GPIOs used for IRQs shall not be set as output */ |
1032 | if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) { | |
1033 | gpiod_err(desc, | |
1034 | "%s: tried to set a GPIO tied to an IRQ as output\n", | |
1035 | __func__); | |
1036 | return -EIO; | |
1037 | } | |
1038 | ||
aca5ce14 LD |
1039 | /* Open drain pin should not be driven to 1 */ |
1040 | if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
372e722e | 1041 | return gpiod_direction_input(desc); |
aca5ce14 | 1042 | |
25553ff0 LD |
1043 | /* Open source pin should not be driven to 0 */ |
1044 | if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
372e722e | 1045 | return gpiod_direction_input(desc); |
25553ff0 | 1046 | |
be1a4b13 LW |
1047 | chip = desc->chip; |
1048 | if (!chip->set || !chip->direction_output) { | |
6424de5a MB |
1049 | gpiod_warn(desc, |
1050 | "%s: missing set() or direction_output() operations\n", | |
1051 | __func__); | |
be1a4b13 LW |
1052 | return -EIO; |
1053 | } | |
1054 | ||
d82da797 | 1055 | status = chip->direction_output(chip, gpio_chip_hwgpio(desc), value); |
d2876d08 DB |
1056 | if (status == 0) |
1057 | set_bit(FLAG_IS_OUT, &desc->flags); | |
372e722e AC |
1058 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
1059 | trace_gpio_direction(desc_to_gpio(desc), 0, status); | |
d2876d08 DB |
1060 | return status; |
1061 | } | |
ef70bbe1 PZ |
1062 | |
1063 | /** | |
1064 | * gpiod_direction_output_raw - set the GPIO direction to output | |
1065 | * @desc: GPIO to set to output | |
1066 | * @value: initial output value of the GPIO | |
1067 | * | |
1068 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
1069 | * be called safely on it. The initial value of the output must be specified | |
1070 | * as raw value on the physical line without regard for the ACTIVE_LOW status. | |
1071 | * | |
1072 | * Return 0 in case of success, else an error code. | |
1073 | */ | |
1074 | int gpiod_direction_output_raw(struct gpio_desc *desc, int value) | |
1075 | { | |
1076 | if (!desc || !desc->chip) { | |
1077 | pr_warn("%s: invalid GPIO\n", __func__); | |
1078 | return -EINVAL; | |
1079 | } | |
1080 | return _gpiod_direction_output_raw(desc, value); | |
1081 | } | |
1082 | EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); | |
1083 | ||
1084 | /** | |
90df4fe0 | 1085 | * gpiod_direction_output - set the GPIO direction to output |
ef70bbe1 PZ |
1086 | * @desc: GPIO to set to output |
1087 | * @value: initial output value of the GPIO | |
1088 | * | |
1089 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
1090 | * be called safely on it. The initial value of the output must be specified | |
1091 | * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1092 | * account. | |
1093 | * | |
1094 | * Return 0 in case of success, else an error code. | |
1095 | */ | |
1096 | int gpiod_direction_output(struct gpio_desc *desc, int value) | |
1097 | { | |
1098 | if (!desc || !desc->chip) { | |
1099 | pr_warn("%s: invalid GPIO\n", __func__); | |
1100 | return -EINVAL; | |
1101 | } | |
1102 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1103 | value = !value; | |
1104 | return _gpiod_direction_output_raw(desc, value); | |
1105 | } | |
79a9becd | 1106 | EXPORT_SYMBOL_GPL(gpiod_direction_output); |
d2876d08 | 1107 | |
c4b5be98 | 1108 | /** |
79a9becd | 1109 | * gpiod_set_debounce - sets @debounce time for a @gpio |
c4b5be98 FB |
1110 | * @gpio: the gpio to set debounce time |
1111 | * @debounce: debounce time is microseconds | |
65d87656 LW |
1112 | * |
1113 | * returns -ENOTSUPP if the controller does not support setting | |
1114 | * debounce. | |
c4b5be98 | 1115 | */ |
79a9becd | 1116 | int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) |
c4b5be98 | 1117 | { |
c4b5be98 | 1118 | struct gpio_chip *chip; |
c4b5be98 | 1119 | |
be1a4b13 | 1120 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1121 | pr_warn("%s: invalid GPIO\n", __func__); |
1122 | return -EINVAL; | |
1123 | } | |
1124 | ||
c4b5be98 | 1125 | chip = desc->chip; |
be1a4b13 | 1126 | if (!chip->set || !chip->set_debounce) { |
6424de5a MB |
1127 | gpiod_dbg(desc, |
1128 | "%s: missing set() or set_debounce() operations\n", | |
1129 | __func__); | |
65d87656 | 1130 | return -ENOTSUPP; |
be1a4b13 LW |
1131 | } |
1132 | ||
d82da797 | 1133 | return chip->set_debounce(chip, gpio_chip_hwgpio(desc), debounce); |
c4b5be98 | 1134 | } |
79a9becd | 1135 | EXPORT_SYMBOL_GPL(gpiod_set_debounce); |
372e722e | 1136 | |
79a9becd AC |
1137 | /** |
1138 | * gpiod_is_active_low - test whether a GPIO is active-low or not | |
1139 | * @desc: the gpio descriptor to test | |
1140 | * | |
1141 | * Returns 1 if the GPIO is active-low, 0 otherwise. | |
1142 | */ | |
1143 | int gpiod_is_active_low(const struct gpio_desc *desc) | |
372e722e | 1144 | { |
79a9becd | 1145 | return test_bit(FLAG_ACTIVE_LOW, &desc->flags); |
372e722e | 1146 | } |
79a9becd | 1147 | EXPORT_SYMBOL_GPL(gpiod_is_active_low); |
d2876d08 DB |
1148 | |
1149 | /* I/O calls are only valid after configuration completed; the relevant | |
1150 | * "is this a valid GPIO" error checks should already have been done. | |
1151 | * | |
1152 | * "Get" operations are often inlinable as reading a pin value register, | |
1153 | * and masking the relevant bit in that register. | |
1154 | * | |
1155 | * When "set" operations are inlinable, they involve writing that mask to | |
1156 | * one register to set a low value, or a different register to set it high. | |
1157 | * Otherwise locking is needed, so there may be little value to inlining. | |
1158 | * | |
1159 | *------------------------------------------------------------------------ | |
1160 | * | |
1161 | * IMPORTANT!!! The hot paths -- get/set value -- assume that callers | |
1162 | * have requested the GPIO. That can include implicit requesting by | |
1163 | * a direction setting call. Marking a gpio as requested locks its chip | |
1164 | * in memory, guaranteeing that these table lookups need no more locking | |
1165 | * and that gpiochip_remove() will fail. | |
1166 | * | |
1167 | * REVISIT when debugging, consider adding some instrumentation to ensure | |
1168 | * that the GPIO was actually requested. | |
1169 | */ | |
1170 | ||
23600969 | 1171 | static bool _gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 DB |
1172 | { |
1173 | struct gpio_chip *chip; | |
23600969 | 1174 | bool value; |
372e722e | 1175 | int offset; |
d2876d08 | 1176 | |
372e722e AC |
1177 | chip = desc->chip; |
1178 | offset = gpio_chip_hwgpio(desc); | |
23600969 | 1179 | value = chip->get ? chip->get(chip, offset) : false; |
372e722e | 1180 | trace_gpio_value(desc_to_gpio(desc), 1, value); |
3f397c21 | 1181 | return value; |
d2876d08 | 1182 | } |
372e722e | 1183 | |
d2876d08 | 1184 | /** |
79a9becd AC |
1185 | * gpiod_get_raw_value() - return a gpio's raw value |
1186 | * @desc: gpio whose value will be returned | |
d2876d08 | 1187 | * |
79a9becd AC |
1188 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding |
1189 | * its ACTIVE_LOW status. | |
1190 | * | |
1191 | * This function should be called from contexts where we cannot sleep, and will | |
1192 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1193 | */ |
79a9becd | 1194 | int gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 | 1195 | { |
bcabdef1 AC |
1196 | if (!desc) |
1197 | return 0; | |
e4e449e8 | 1198 | /* Should be using gpio_get_value_cansleep() */ |
d8e0ac08 | 1199 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 1200 | return _gpiod_get_raw_value(desc); |
d2876d08 | 1201 | } |
79a9becd | 1202 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value); |
372e722e | 1203 | |
79a9becd AC |
1204 | /** |
1205 | * gpiod_get_value() - return a gpio's value | |
1206 | * @desc: gpio whose value will be returned | |
1207 | * | |
1208 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
1209 | * account. | |
1210 | * | |
1211 | * This function should be called from contexts where we cannot sleep, and will | |
1212 | * complain if the GPIO chip functions potentially sleep. | |
1213 | */ | |
1214 | int gpiod_get_value(const struct gpio_desc *desc) | |
372e722e | 1215 | { |
79a9becd AC |
1216 | int value; |
1217 | if (!desc) | |
1218 | return 0; | |
1219 | /* Should be using gpio_get_value_cansleep() */ | |
1220 | WARN_ON(desc->chip->can_sleep); | |
1221 | ||
1222 | value = _gpiod_get_raw_value(desc); | |
1223 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1224 | value = !value; | |
1225 | ||
1226 | return value; | |
372e722e | 1227 | } |
79a9becd | 1228 | EXPORT_SYMBOL_GPL(gpiod_get_value); |
d2876d08 | 1229 | |
aca5ce14 LD |
1230 | /* |
1231 | * _gpio_set_open_drain_value() - Set the open drain gpio's value. | |
79a9becd | 1232 | * @desc: gpio descriptor whose state need to be set. |
20a8a968 | 1233 | * @value: Non-zero for setting it HIGH otherwise it will set to LOW. |
aca5ce14 | 1234 | */ |
23600969 | 1235 | static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value) |
aca5ce14 LD |
1236 | { |
1237 | int err = 0; | |
372e722e AC |
1238 | struct gpio_chip *chip = desc->chip; |
1239 | int offset = gpio_chip_hwgpio(desc); | |
1240 | ||
aca5ce14 | 1241 | if (value) { |
372e722e | 1242 | err = chip->direction_input(chip, offset); |
aca5ce14 | 1243 | if (!err) |
372e722e | 1244 | clear_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 1245 | } else { |
372e722e | 1246 | err = chip->direction_output(chip, offset, 0); |
aca5ce14 | 1247 | if (!err) |
372e722e | 1248 | set_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 1249 | } |
372e722e | 1250 | trace_gpio_direction(desc_to_gpio(desc), value, err); |
aca5ce14 | 1251 | if (err < 0) |
6424de5a MB |
1252 | gpiod_err(desc, |
1253 | "%s: Error in set_value for open drain err %d\n", | |
1254 | __func__, err); | |
aca5ce14 LD |
1255 | } |
1256 | ||
25553ff0 | 1257 | /* |
79a9becd AC |
1258 | * _gpio_set_open_source_value() - Set the open source gpio's value. |
1259 | * @desc: gpio descriptor whose state need to be set. | |
20a8a968 | 1260 | * @value: Non-zero for setting it HIGH otherwise it will set to LOW. |
25553ff0 | 1261 | */ |
23600969 | 1262 | static void _gpio_set_open_source_value(struct gpio_desc *desc, bool value) |
25553ff0 LD |
1263 | { |
1264 | int err = 0; | |
372e722e AC |
1265 | struct gpio_chip *chip = desc->chip; |
1266 | int offset = gpio_chip_hwgpio(desc); | |
1267 | ||
25553ff0 | 1268 | if (value) { |
372e722e | 1269 | err = chip->direction_output(chip, offset, 1); |
25553ff0 | 1270 | if (!err) |
372e722e | 1271 | set_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 1272 | } else { |
372e722e | 1273 | err = chip->direction_input(chip, offset); |
25553ff0 | 1274 | if (!err) |
372e722e | 1275 | clear_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 1276 | } |
372e722e | 1277 | trace_gpio_direction(desc_to_gpio(desc), !value, err); |
25553ff0 | 1278 | if (err < 0) |
6424de5a MB |
1279 | gpiod_err(desc, |
1280 | "%s: Error in set_value for open source err %d\n", | |
1281 | __func__, err); | |
25553ff0 LD |
1282 | } |
1283 | ||
23600969 | 1284 | static void _gpiod_set_raw_value(struct gpio_desc *desc, bool value) |
d2876d08 DB |
1285 | { |
1286 | struct gpio_chip *chip; | |
1287 | ||
372e722e | 1288 | chip = desc->chip; |
372e722e AC |
1289 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
1290 | if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
1291 | _gpio_set_open_drain_value(desc, value); | |
1292 | else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
1293 | _gpio_set_open_source_value(desc, value); | |
aca5ce14 | 1294 | else |
372e722e AC |
1295 | chip->set(chip, gpio_chip_hwgpio(desc), value); |
1296 | } | |
1297 | ||
5f424243 RI |
1298 | /* |
1299 | * set multiple outputs on the same chip; | |
1300 | * use the chip's set_multiple function if available; | |
1301 | * otherwise set the outputs sequentially; | |
1302 | * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word | |
1303 | * defines which outputs are to be changed | |
1304 | * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word | |
1305 | * defines the values the outputs specified by mask are to be set to | |
1306 | */ | |
1307 | static void gpio_chip_set_multiple(struct gpio_chip *chip, | |
1308 | unsigned long *mask, unsigned long *bits) | |
1309 | { | |
1310 | if (chip->set_multiple) { | |
1311 | chip->set_multiple(chip, mask, bits); | |
1312 | } else { | |
1313 | int i; | |
1314 | for (i = 0; i < chip->ngpio; i++) { | |
1315 | if (mask[BIT_WORD(i)] == 0) { | |
1316 | /* no more set bits in this mask word; | |
1317 | * skip ahead to the next word */ | |
1318 | i = (BIT_WORD(i) + 1) * BITS_PER_LONG - 1; | |
1319 | continue; | |
1320 | } | |
1321 | /* set outputs if the corresponding mask bit is set */ | |
38e003f4 | 1322 | if (__test_and_clear_bit(i, mask)) |
5f424243 | 1323 | chip->set(chip, i, test_bit(i, bits)); |
5f424243 RI |
1324 | } |
1325 | } | |
1326 | } | |
1327 | ||
3fff99bc RI |
1328 | static void gpiod_set_array_value_priv(bool raw, bool can_sleep, |
1329 | unsigned int array_size, | |
1330 | struct gpio_desc **desc_array, | |
1331 | int *value_array) | |
5f424243 RI |
1332 | { |
1333 | int i = 0; | |
1334 | ||
1335 | while (i < array_size) { | |
1336 | struct gpio_chip *chip = desc_array[i]->chip; | |
1337 | unsigned long mask[BITS_TO_LONGS(chip->ngpio)]; | |
1338 | unsigned long bits[BITS_TO_LONGS(chip->ngpio)]; | |
1339 | int count = 0; | |
1340 | ||
38e003f4 | 1341 | if (!can_sleep) |
5f424243 | 1342 | WARN_ON(chip->can_sleep); |
38e003f4 | 1343 | |
5f424243 RI |
1344 | memset(mask, 0, sizeof(mask)); |
1345 | do { | |
1346 | struct gpio_desc *desc = desc_array[i]; | |
1347 | int hwgpio = gpio_chip_hwgpio(desc); | |
1348 | int value = value_array[i]; | |
1349 | ||
1350 | if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1351 | value = !value; | |
1352 | trace_gpio_value(desc_to_gpio(desc), 0, value); | |
1353 | /* | |
1354 | * collect all normal outputs belonging to the same chip | |
1355 | * open drain and open source outputs are set individually | |
1356 | */ | |
1357 | if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { | |
38e003f4 | 1358 | _gpio_set_open_drain_value(desc, value); |
5f424243 RI |
1359 | } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) { |
1360 | _gpio_set_open_source_value(desc, value); | |
1361 | } else { | |
1362 | __set_bit(hwgpio, mask); | |
38e003f4 | 1363 | if (value) |
5f424243 | 1364 | __set_bit(hwgpio, bits); |
38e003f4 | 1365 | else |
5f424243 | 1366 | __clear_bit(hwgpio, bits); |
5f424243 RI |
1367 | count++; |
1368 | } | |
1369 | i++; | |
1370 | } while ((i < array_size) && (desc_array[i]->chip == chip)); | |
1371 | /* push collected bits to outputs */ | |
38e003f4 | 1372 | if (count != 0) |
5f424243 | 1373 | gpio_chip_set_multiple(chip, mask, bits); |
5f424243 RI |
1374 | } |
1375 | } | |
1376 | ||
d2876d08 | 1377 | /** |
79a9becd AC |
1378 | * gpiod_set_raw_value() - assign a gpio's raw value |
1379 | * @desc: gpio whose value will be assigned | |
d2876d08 | 1380 | * @value: value to assign |
d2876d08 | 1381 | * |
79a9becd AC |
1382 | * Set the raw value of the GPIO, i.e. the value of its physical line without |
1383 | * regard for its ACTIVE_LOW status. | |
1384 | * | |
1385 | * This function should be called from contexts where we cannot sleep, and will | |
1386 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1387 | */ |
79a9becd | 1388 | void gpiod_set_raw_value(struct gpio_desc *desc, int value) |
372e722e | 1389 | { |
bcabdef1 AC |
1390 | if (!desc) |
1391 | return; | |
e4e449e8 | 1392 | /* Should be using gpio_set_value_cansleep() */ |
d8e0ac08 | 1393 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 1394 | _gpiod_set_raw_value(desc, value); |
d2876d08 | 1395 | } |
79a9becd | 1396 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value); |
d2876d08 DB |
1397 | |
1398 | /** | |
79a9becd AC |
1399 | * gpiod_set_value() - assign a gpio's value |
1400 | * @desc: gpio whose value will be assigned | |
1401 | * @value: value to assign | |
1402 | * | |
1403 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1404 | * account | |
d2876d08 | 1405 | * |
79a9becd AC |
1406 | * This function should be called from contexts where we cannot sleep, and will |
1407 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1408 | */ |
79a9becd | 1409 | void gpiod_set_value(struct gpio_desc *desc, int value) |
d2876d08 | 1410 | { |
bcabdef1 | 1411 | if (!desc) |
79a9becd AC |
1412 | return; |
1413 | /* Should be using gpio_set_value_cansleep() */ | |
1414 | WARN_ON(desc->chip->can_sleep); | |
1415 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1416 | value = !value; | |
1417 | _gpiod_set_raw_value(desc, value); | |
372e722e | 1418 | } |
79a9becd | 1419 | EXPORT_SYMBOL_GPL(gpiod_set_value); |
d2876d08 | 1420 | |
5f424243 | 1421 | /** |
3fff99bc | 1422 | * gpiod_set_raw_array_value() - assign values to an array of GPIOs |
5f424243 RI |
1423 | * @array_size: number of elements in the descriptor / value arrays |
1424 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1425 | * @value_array: array of values to assign | |
1426 | * | |
1427 | * Set the raw values of the GPIOs, i.e. the values of the physical lines | |
1428 | * without regard for their ACTIVE_LOW status. | |
1429 | * | |
1430 | * This function should be called from contexts where we cannot sleep, and will | |
1431 | * complain if the GPIO chip functions potentially sleep. | |
1432 | */ | |
3fff99bc | 1433 | void gpiod_set_raw_array_value(unsigned int array_size, |
5f424243 RI |
1434 | struct gpio_desc **desc_array, int *value_array) |
1435 | { | |
1436 | if (!desc_array) | |
1437 | return; | |
3fff99bc RI |
1438 | gpiod_set_array_value_priv(true, false, array_size, desc_array, |
1439 | value_array); | |
5f424243 | 1440 | } |
3fff99bc | 1441 | EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value); |
5f424243 RI |
1442 | |
1443 | /** | |
3fff99bc | 1444 | * gpiod_set_array_value() - assign values to an array of GPIOs |
5f424243 RI |
1445 | * @array_size: number of elements in the descriptor / value arrays |
1446 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1447 | * @value_array: array of values to assign | |
1448 | * | |
1449 | * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status | |
1450 | * into account. | |
1451 | * | |
1452 | * This function should be called from contexts where we cannot sleep, and will | |
1453 | * complain if the GPIO chip functions potentially sleep. | |
1454 | */ | |
3fff99bc RI |
1455 | void gpiod_set_array_value(unsigned int array_size, |
1456 | struct gpio_desc **desc_array, int *value_array) | |
5f424243 RI |
1457 | { |
1458 | if (!desc_array) | |
1459 | return; | |
3fff99bc RI |
1460 | gpiod_set_array_value_priv(false, false, array_size, desc_array, |
1461 | value_array); | |
5f424243 | 1462 | } |
3fff99bc | 1463 | EXPORT_SYMBOL_GPL(gpiod_set_array_value); |
5f424243 | 1464 | |
d2876d08 | 1465 | /** |
79a9becd AC |
1466 | * gpiod_cansleep() - report whether gpio value access may sleep |
1467 | * @desc: gpio to check | |
d2876d08 | 1468 | * |
d2876d08 | 1469 | */ |
79a9becd | 1470 | int gpiod_cansleep(const struct gpio_desc *desc) |
372e722e | 1471 | { |
bcabdef1 AC |
1472 | if (!desc) |
1473 | return 0; | |
372e722e | 1474 | return desc->chip->can_sleep; |
d2876d08 | 1475 | } |
79a9becd | 1476 | EXPORT_SYMBOL_GPL(gpiod_cansleep); |
d2876d08 | 1477 | |
0f6d504e | 1478 | /** |
79a9becd AC |
1479 | * gpiod_to_irq() - return the IRQ corresponding to a GPIO |
1480 | * @desc: gpio whose IRQ will be returned (already requested) | |
0f6d504e | 1481 | * |
79a9becd AC |
1482 | * Return the IRQ corresponding to the passed GPIO, or an error code in case of |
1483 | * error. | |
0f6d504e | 1484 | */ |
79a9becd | 1485 | int gpiod_to_irq(const struct gpio_desc *desc) |
0f6d504e DB |
1486 | { |
1487 | struct gpio_chip *chip; | |
372e722e | 1488 | int offset; |
0f6d504e | 1489 | |
bcabdef1 AC |
1490 | if (!desc) |
1491 | return -EINVAL; | |
372e722e AC |
1492 | chip = desc->chip; |
1493 | offset = gpio_chip_hwgpio(desc); | |
1494 | return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO; | |
0f6d504e | 1495 | } |
79a9becd | 1496 | EXPORT_SYMBOL_GPL(gpiod_to_irq); |
0f6d504e | 1497 | |
d468bf9e | 1498 | /** |
e3a2e878 | 1499 | * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ |
d74be6df AC |
1500 | * @chip: the chip the GPIO to lock belongs to |
1501 | * @offset: the offset of the GPIO to lock as IRQ | |
d468bf9e LW |
1502 | * |
1503 | * This is used directly by GPIO drivers that want to lock down | |
f438acdf | 1504 | * a certain GPIO line to be used for IRQs. |
d468bf9e | 1505 | */ |
e3a2e878 | 1506 | int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset) |
372e722e | 1507 | { |
d74be6df | 1508 | if (offset >= chip->ngpio) |
d468bf9e LW |
1509 | return -EINVAL; |
1510 | ||
d74be6df AC |
1511 | if (test_bit(FLAG_IS_OUT, &chip->desc[offset].flags)) { |
1512 | chip_err(chip, | |
d468bf9e LW |
1513 | "%s: tried to flag a GPIO set as output for IRQ\n", |
1514 | __func__); | |
1515 | return -EIO; | |
1516 | } | |
1517 | ||
d74be6df | 1518 | set_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags); |
d468bf9e | 1519 | return 0; |
372e722e | 1520 | } |
e3a2e878 | 1521 | EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq); |
d2876d08 | 1522 | |
d468bf9e | 1523 | /** |
e3a2e878 | 1524 | * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ |
d74be6df AC |
1525 | * @chip: the chip the GPIO to lock belongs to |
1526 | * @offset: the offset of the GPIO to lock as IRQ | |
d468bf9e LW |
1527 | * |
1528 | * This is used directly by GPIO drivers that want to indicate | |
1529 | * that a certain GPIO is no longer used exclusively for IRQ. | |
d2876d08 | 1530 | */ |
e3a2e878 | 1531 | void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) |
d468bf9e | 1532 | { |
d74be6df | 1533 | if (offset >= chip->ngpio) |
d468bf9e | 1534 | return; |
d2876d08 | 1535 | |
d74be6df | 1536 | clear_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags); |
d468bf9e | 1537 | } |
e3a2e878 | 1538 | EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq); |
d468bf9e | 1539 | |
79a9becd AC |
1540 | /** |
1541 | * gpiod_get_raw_value_cansleep() - return a gpio's raw value | |
1542 | * @desc: gpio whose value will be returned | |
1543 | * | |
1544 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding | |
1545 | * its ACTIVE_LOW status. | |
1546 | * | |
1547 | * This function is to be called from contexts that can sleep. | |
d2876d08 | 1548 | */ |
79a9becd | 1549 | int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) |
d2876d08 | 1550 | { |
d2876d08 | 1551 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1552 | if (!desc) |
1553 | return 0; | |
79a9becd | 1554 | return _gpiod_get_raw_value(desc); |
d2876d08 | 1555 | } |
79a9becd | 1556 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); |
372e722e | 1557 | |
79a9becd AC |
1558 | /** |
1559 | * gpiod_get_value_cansleep() - return a gpio's value | |
1560 | * @desc: gpio whose value will be returned | |
1561 | * | |
1562 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
1563 | * account. | |
1564 | * | |
1565 | * This function is to be called from contexts that can sleep. | |
1566 | */ | |
1567 | int gpiod_get_value_cansleep(const struct gpio_desc *desc) | |
d2876d08 | 1568 | { |
3f397c21 | 1569 | int value; |
d2876d08 DB |
1570 | |
1571 | might_sleep_if(extra_checks); | |
bcabdef1 AC |
1572 | if (!desc) |
1573 | return 0; | |
79a9becd AC |
1574 | |
1575 | value = _gpiod_get_raw_value(desc); | |
1576 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1577 | value = !value; | |
1578 | ||
3f397c21 | 1579 | return value; |
d2876d08 | 1580 | } |
79a9becd | 1581 | EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); |
372e722e | 1582 | |
79a9becd AC |
1583 | /** |
1584 | * gpiod_set_raw_value_cansleep() - assign a gpio's raw value | |
1585 | * @desc: gpio whose value will be assigned | |
1586 | * @value: value to assign | |
1587 | * | |
1588 | * Set the raw value of the GPIO, i.e. the value of its physical line without | |
1589 | * regard for its ACTIVE_LOW status. | |
1590 | * | |
1591 | * This function is to be called from contexts that can sleep. | |
1592 | */ | |
1593 | void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) | |
372e722e | 1594 | { |
d2876d08 | 1595 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1596 | if (!desc) |
1597 | return; | |
79a9becd | 1598 | _gpiod_set_raw_value(desc, value); |
372e722e | 1599 | } |
79a9becd | 1600 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); |
d2876d08 | 1601 | |
79a9becd AC |
1602 | /** |
1603 | * gpiod_set_value_cansleep() - assign a gpio's value | |
1604 | * @desc: gpio whose value will be assigned | |
1605 | * @value: value to assign | |
1606 | * | |
1607 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1608 | * account | |
1609 | * | |
1610 | * This function is to be called from contexts that can sleep. | |
1611 | */ | |
1612 | void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) | |
d2876d08 | 1613 | { |
d2876d08 | 1614 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1615 | if (!desc) |
1616 | return; | |
79a9becd AC |
1617 | |
1618 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1619 | value = !value; | |
1620 | _gpiod_set_raw_value(desc, value); | |
372e722e | 1621 | } |
79a9becd | 1622 | EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); |
d2876d08 | 1623 | |
5f424243 | 1624 | /** |
3fff99bc | 1625 | * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs |
5f424243 RI |
1626 | * @array_size: number of elements in the descriptor / value arrays |
1627 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1628 | * @value_array: array of values to assign | |
1629 | * | |
1630 | * Set the raw values of the GPIOs, i.e. the values of the physical lines | |
1631 | * without regard for their ACTIVE_LOW status. | |
1632 | * | |
1633 | * This function is to be called from contexts that can sleep. | |
1634 | */ | |
3fff99bc RI |
1635 | void gpiod_set_raw_array_value_cansleep(unsigned int array_size, |
1636 | struct gpio_desc **desc_array, | |
1637 | int *value_array) | |
5f424243 RI |
1638 | { |
1639 | might_sleep_if(extra_checks); | |
1640 | if (!desc_array) | |
1641 | return; | |
3fff99bc RI |
1642 | gpiod_set_array_value_priv(true, true, array_size, desc_array, |
1643 | value_array); | |
5f424243 | 1644 | } |
3fff99bc | 1645 | EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep); |
5f424243 RI |
1646 | |
1647 | /** | |
3fff99bc | 1648 | * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs |
5f424243 RI |
1649 | * @array_size: number of elements in the descriptor / value arrays |
1650 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1651 | * @value_array: array of values to assign | |
1652 | * | |
1653 | * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status | |
1654 | * into account. | |
1655 | * | |
1656 | * This function is to be called from contexts that can sleep. | |
1657 | */ | |
3fff99bc RI |
1658 | void gpiod_set_array_value_cansleep(unsigned int array_size, |
1659 | struct gpio_desc **desc_array, | |
1660 | int *value_array) | |
5f424243 RI |
1661 | { |
1662 | might_sleep_if(extra_checks); | |
1663 | if (!desc_array) | |
1664 | return; | |
3fff99bc RI |
1665 | gpiod_set_array_value_priv(false, true, array_size, desc_array, |
1666 | value_array); | |
5f424243 | 1667 | } |
3fff99bc | 1668 | EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep); |
5f424243 | 1669 | |
bae48da2 | 1670 | /** |
ad824783 AC |
1671 | * gpiod_add_lookup_table() - register GPIO device consumers |
1672 | * @table: table of consumers to register | |
bae48da2 | 1673 | */ |
ad824783 | 1674 | void gpiod_add_lookup_table(struct gpiod_lookup_table *table) |
bae48da2 AC |
1675 | { |
1676 | mutex_lock(&gpio_lookup_lock); | |
1677 | ||
ad824783 | 1678 | list_add_tail(&table->list, &gpio_lookup_list); |
bae48da2 AC |
1679 | |
1680 | mutex_unlock(&gpio_lookup_lock); | |
1681 | } | |
1682 | ||
bae48da2 | 1683 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, |
53e7cac3 AC |
1684 | unsigned int idx, |
1685 | enum gpio_lookup_flags *flags) | |
bae48da2 AC |
1686 | { |
1687 | char prop_name[32]; /* 32 is max size of property name */ | |
1688 | enum of_gpio_flags of_flags; | |
1689 | struct gpio_desc *desc; | |
dd34c37a | 1690 | unsigned int i; |
bae48da2 | 1691 | |
7f2e553a | 1692 | for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { |
dd34c37a | 1693 | if (con_id) |
9e089246 | 1694 | snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id, |
7f2e553a | 1695 | gpio_suffixes[i]); |
dd34c37a | 1696 | else |
9e089246 | 1697 | snprintf(prop_name, sizeof(prop_name), "%s", |
7f2e553a | 1698 | gpio_suffixes[i]); |
bae48da2 | 1699 | |
dd34c37a TR |
1700 | desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx, |
1701 | &of_flags); | |
06fc3b70 | 1702 | if (!IS_ERR(desc) || (PTR_ERR(desc) == -EPROBE_DEFER)) |
dd34c37a TR |
1703 | break; |
1704 | } | |
bae48da2 AC |
1705 | |
1706 | if (IS_ERR(desc)) | |
1707 | return desc; | |
1708 | ||
1709 | if (of_flags & OF_GPIO_ACTIVE_LOW) | |
53e7cac3 | 1710 | *flags |= GPIO_ACTIVE_LOW; |
bae48da2 AC |
1711 | |
1712 | return desc; | |
1713 | } | |
d2876d08 | 1714 | |
81f59e9d | 1715 | static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id, |
53e7cac3 AC |
1716 | unsigned int idx, |
1717 | enum gpio_lookup_flags *flags) | |
372e722e | 1718 | { |
0d9a693c | 1719 | struct acpi_device *adev = ACPI_COMPANION(dev); |
e01f440a MW |
1720 | struct acpi_gpio_info info; |
1721 | struct gpio_desc *desc; | |
0d9a693c MW |
1722 | char propname[32]; |
1723 | int i; | |
e01f440a | 1724 | |
0d9a693c | 1725 | /* Try first from _DSD */ |
7f2e553a | 1726 | for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { |
0d9a693c MW |
1727 | if (con_id && strcmp(con_id, "gpios")) { |
1728 | snprintf(propname, sizeof(propname), "%s-%s", | |
7f2e553a | 1729 | con_id, gpio_suffixes[i]); |
0d9a693c MW |
1730 | } else { |
1731 | snprintf(propname, sizeof(propname), "%s", | |
7f2e553a | 1732 | gpio_suffixes[i]); |
0d9a693c MW |
1733 | } |
1734 | ||
1735 | desc = acpi_get_gpiod_by_index(adev, propname, idx, &info); | |
1736 | if (!IS_ERR(desc) || (PTR_ERR(desc) == -EPROBE_DEFER)) | |
1737 | break; | |
1738 | } | |
1739 | ||
1740 | /* Then from plain _CRS GPIOs */ | |
1741 | if (IS_ERR(desc)) { | |
1742 | desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info); | |
1743 | if (IS_ERR(desc)) | |
1744 | return desc; | |
1745 | } | |
e01f440a | 1746 | |
0d9a693c | 1747 | if (info.active_low) |
53e7cac3 | 1748 | *flags |= GPIO_ACTIVE_LOW; |
e01f440a MW |
1749 | |
1750 | return desc; | |
81f59e9d MW |
1751 | } |
1752 | ||
ad824783 | 1753 | static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) |
bae48da2 AC |
1754 | { |
1755 | const char *dev_id = dev ? dev_name(dev) : NULL; | |
ad824783 | 1756 | struct gpiod_lookup_table *table; |
bae48da2 AC |
1757 | |
1758 | mutex_lock(&gpio_lookup_lock); | |
1759 | ||
ad824783 AC |
1760 | list_for_each_entry(table, &gpio_lookup_list, list) { |
1761 | if (table->dev_id && dev_id) { | |
1762 | /* | |
1763 | * Valid strings on both ends, must be identical to have | |
1764 | * a match | |
1765 | */ | |
1766 | if (!strcmp(table->dev_id, dev_id)) | |
1767 | goto found; | |
1768 | } else { | |
1769 | /* | |
1770 | * One of the pointers is NULL, so both must be to have | |
1771 | * a match | |
1772 | */ | |
1773 | if (dev_id == table->dev_id) | |
1774 | goto found; | |
1775 | } | |
1776 | } | |
1777 | table = NULL; | |
bae48da2 | 1778 | |
ad824783 AC |
1779 | found: |
1780 | mutex_unlock(&gpio_lookup_lock); | |
1781 | return table; | |
1782 | } | |
bae48da2 | 1783 | |
ad824783 AC |
1784 | static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, |
1785 | unsigned int idx, | |
1786 | enum gpio_lookup_flags *flags) | |
1787 | { | |
2a3cf6a3 | 1788 | struct gpio_desc *desc = ERR_PTR(-ENOENT); |
ad824783 AC |
1789 | struct gpiod_lookup_table *table; |
1790 | struct gpiod_lookup *p; | |
bae48da2 | 1791 | |
ad824783 AC |
1792 | table = gpiod_find_lookup_table(dev); |
1793 | if (!table) | |
1794 | return desc; | |
bae48da2 | 1795 | |
ad824783 AC |
1796 | for (p = &table->table[0]; p->chip_label; p++) { |
1797 | struct gpio_chip *chip; | |
bae48da2 | 1798 | |
ad824783 | 1799 | /* idx must always match exactly */ |
bae48da2 AC |
1800 | if (p->idx != idx) |
1801 | continue; | |
1802 | ||
ad824783 AC |
1803 | /* If the lookup entry has a con_id, require exact match */ |
1804 | if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) | |
1805 | continue; | |
bae48da2 | 1806 | |
ad824783 | 1807 | chip = find_chip_by_name(p->chip_label); |
bae48da2 | 1808 | |
ad824783 | 1809 | if (!chip) { |
2a3cf6a3 AC |
1810 | dev_err(dev, "cannot find GPIO chip %s\n", |
1811 | p->chip_label); | |
1812 | return ERR_PTR(-ENODEV); | |
ad824783 | 1813 | } |
bae48da2 | 1814 | |
ad824783 | 1815 | if (chip->ngpio <= p->chip_hwnum) { |
2a3cf6a3 AC |
1816 | dev_err(dev, |
1817 | "requested GPIO %d is out of range [0..%d] for chip %s\n", | |
1818 | idx, chip->ngpio, chip->label); | |
1819 | return ERR_PTR(-EINVAL); | |
bae48da2 | 1820 | } |
bae48da2 | 1821 | |
bb1e88cc | 1822 | desc = gpiochip_get_desc(chip, p->chip_hwnum); |
ad824783 | 1823 | *flags = p->flags; |
bae48da2 | 1824 | |
2a3cf6a3 | 1825 | return desc; |
bae48da2 AC |
1826 | } |
1827 | ||
bae48da2 AC |
1828 | return desc; |
1829 | } | |
1830 | ||
66858527 RI |
1831 | static int dt_gpio_count(struct device *dev, const char *con_id) |
1832 | { | |
1833 | int ret; | |
1834 | char propname[32]; | |
1835 | unsigned int i; | |
1836 | ||
1837 | for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { | |
1838 | if (con_id) | |
1839 | snprintf(propname, sizeof(propname), "%s-%s", | |
1840 | con_id, gpio_suffixes[i]); | |
1841 | else | |
1842 | snprintf(propname, sizeof(propname), "%s", | |
1843 | gpio_suffixes[i]); | |
1844 | ||
1845 | ret = of_gpio_named_count(dev->of_node, propname); | |
1846 | if (ret >= 0) | |
1847 | break; | |
1848 | } | |
1849 | return ret; | |
1850 | } | |
1851 | ||
1852 | static int platform_gpio_count(struct device *dev, const char *con_id) | |
1853 | { | |
1854 | struct gpiod_lookup_table *table; | |
1855 | struct gpiod_lookup *p; | |
1856 | unsigned int count = 0; | |
1857 | ||
1858 | table = gpiod_find_lookup_table(dev); | |
1859 | if (!table) | |
1860 | return -ENOENT; | |
1861 | ||
1862 | for (p = &table->table[0]; p->chip_label; p++) { | |
1863 | if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) || | |
1864 | (!con_id && !p->con_id)) | |
1865 | count++; | |
1866 | } | |
1867 | if (!count) | |
1868 | return -ENOENT; | |
1869 | ||
1870 | return count; | |
1871 | } | |
1872 | ||
1873 | /** | |
1874 | * gpiod_count - return the number of GPIOs associated with a device / function | |
1875 | * or -ENOENT if no GPIO has been assigned to the requested function | |
1876 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
1877 | * @con_id: function within the GPIO consumer | |
1878 | */ | |
1879 | int gpiod_count(struct device *dev, const char *con_id) | |
1880 | { | |
1881 | int count = -ENOENT; | |
1882 | ||
1883 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) | |
1884 | count = dt_gpio_count(dev, con_id); | |
1885 | else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) | |
1886 | count = acpi_gpio_count(dev, con_id); | |
1887 | ||
1888 | if (count < 0) | |
1889 | count = platform_gpio_count(dev, con_id); | |
1890 | ||
1891 | return count; | |
1892 | } | |
1893 | EXPORT_SYMBOL_GPL(gpiod_count); | |
1894 | ||
bae48da2 | 1895 | /** |
0879162f | 1896 | * gpiod_get - obtain a GPIO for a given GPIO function |
ad824783 | 1897 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 | 1898 | * @con_id: function within the GPIO consumer |
39b2bbe3 | 1899 | * @flags: optional GPIO initialization flags |
bae48da2 AC |
1900 | * |
1901 | * Return the GPIO descriptor corresponding to the function con_id of device | |
2a3cf6a3 | 1902 | * dev, -ENOENT if no GPIO has been assigned to the requested function, or |
20a8a968 | 1903 | * another IS_ERR() code if an error occurred while trying to acquire the GPIO. |
bae48da2 | 1904 | */ |
b17d1bf1 | 1905 | struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id, |
39b2bbe3 | 1906 | enum gpiod_flags flags) |
bae48da2 | 1907 | { |
39b2bbe3 | 1908 | return gpiod_get_index(dev, con_id, 0, flags); |
bae48da2 | 1909 | } |
b17d1bf1 | 1910 | EXPORT_SYMBOL_GPL(gpiod_get); |
bae48da2 | 1911 | |
29a1f233 TR |
1912 | /** |
1913 | * gpiod_get_optional - obtain an optional GPIO for a given GPIO function | |
1914 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
1915 | * @con_id: function within the GPIO consumer | |
39b2bbe3 | 1916 | * @flags: optional GPIO initialization flags |
29a1f233 TR |
1917 | * |
1918 | * This is equivalent to gpiod_get(), except that when no GPIO was assigned to | |
1919 | * the requested function it will return NULL. This is convenient for drivers | |
1920 | * that need to handle optional GPIOs. | |
1921 | */ | |
b17d1bf1 | 1922 | struct gpio_desc *__must_check gpiod_get_optional(struct device *dev, |
39b2bbe3 AC |
1923 | const char *con_id, |
1924 | enum gpiod_flags flags) | |
29a1f233 | 1925 | { |
39b2bbe3 | 1926 | return gpiod_get_index_optional(dev, con_id, 0, flags); |
29a1f233 | 1927 | } |
b17d1bf1 | 1928 | EXPORT_SYMBOL_GPL(gpiod_get_optional); |
29a1f233 | 1929 | |
f625d460 BP |
1930 | |
1931 | /** | |
1932 | * gpiod_configure_flags - helper function to configure a given GPIO | |
1933 | * @desc: gpio whose value will be assigned | |
1934 | * @con_id: function within the GPIO consumer | |
1935 | * @lflags: gpio_lookup_flags - returned from of_find_gpio() or | |
1936 | * of_get_gpio_hog() | |
1937 | * @dflags: gpiod_flags - optional GPIO initialization flags | |
1938 | * | |
1939 | * Return 0 on success, -ENOENT if no GPIO has been assigned to the | |
1940 | * requested function and/or index, or another IS_ERR() code if an error | |
1941 | * occurred while trying to acquire the GPIO. | |
1942 | */ | |
1943 | static int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, | |
1944 | unsigned long lflags, enum gpiod_flags dflags) | |
1945 | { | |
1946 | int status; | |
1947 | ||
1948 | if (lflags & GPIO_ACTIVE_LOW) | |
1949 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
1950 | if (lflags & GPIO_OPEN_DRAIN) | |
1951 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); | |
1952 | if (lflags & GPIO_OPEN_SOURCE) | |
1953 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); | |
1954 | ||
1955 | /* No particular flag request, return here... */ | |
1956 | if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) { | |
1957 | pr_debug("no flags found for %s\n", con_id); | |
1958 | return 0; | |
1959 | } | |
1960 | ||
1961 | /* Process flags */ | |
1962 | if (dflags & GPIOD_FLAGS_BIT_DIR_OUT) | |
1963 | status = gpiod_direction_output(desc, | |
1964 | dflags & GPIOD_FLAGS_BIT_DIR_VAL); | |
1965 | else | |
1966 | status = gpiod_direction_input(desc); | |
1967 | ||
1968 | return status; | |
1969 | } | |
1970 | ||
bae48da2 AC |
1971 | /** |
1972 | * gpiod_get_index - obtain a GPIO from a multi-index GPIO function | |
fdd6a5fe | 1973 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 AC |
1974 | * @con_id: function within the GPIO consumer |
1975 | * @idx: index of the GPIO to obtain in the consumer | |
39b2bbe3 | 1976 | * @flags: optional GPIO initialization flags |
bae48da2 AC |
1977 | * |
1978 | * This variant of gpiod_get() allows to access GPIOs other than the first | |
1979 | * defined one for functions that define several GPIOs. | |
1980 | * | |
2a3cf6a3 AC |
1981 | * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the |
1982 | * requested function and/or index, or another IS_ERR() code if an error | |
20a8a968 | 1983 | * occurred while trying to acquire the GPIO. |
bae48da2 | 1984 | */ |
b17d1bf1 | 1985 | struct gpio_desc *__must_check gpiod_get_index(struct device *dev, |
bae48da2 | 1986 | const char *con_id, |
39b2bbe3 AC |
1987 | unsigned int idx, |
1988 | enum gpiod_flags flags) | |
bae48da2 | 1989 | { |
35c5d7fd | 1990 | struct gpio_desc *desc = NULL; |
bae48da2 | 1991 | int status; |
39b2bbe3 | 1992 | enum gpio_lookup_flags lookupflags = 0; |
bae48da2 AC |
1993 | |
1994 | dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); | |
1995 | ||
4d8440b9 RW |
1996 | if (dev) { |
1997 | /* Using device tree? */ | |
1998 | if (IS_ENABLED(CONFIG_OF) && dev->of_node) { | |
1999 | dev_dbg(dev, "using device tree for GPIO lookup\n"); | |
2000 | desc = of_find_gpio(dev, con_id, idx, &lookupflags); | |
2001 | } else if (ACPI_COMPANION(dev)) { | |
2002 | dev_dbg(dev, "using ACPI for GPIO lookup\n"); | |
2003 | desc = acpi_find_gpio(dev, con_id, idx, &lookupflags); | |
2004 | } | |
35c5d7fd AC |
2005 | } |
2006 | ||
2007 | /* | |
2008 | * Either we are not using DT or ACPI, or their lookup did not return | |
2009 | * a result. In that case, use platform lookup as a fallback. | |
2010 | */ | |
2a3cf6a3 | 2011 | if (!desc || desc == ERR_PTR(-ENOENT)) { |
43a8785a | 2012 | dev_dbg(dev, "using lookup tables for GPIO lookup\n"); |
39b2bbe3 | 2013 | desc = gpiod_find(dev, con_id, idx, &lookupflags); |
bae48da2 AC |
2014 | } |
2015 | ||
2016 | if (IS_ERR(desc)) { | |
351cfe0f | 2017 | dev_dbg(dev, "lookup for GPIO %s failed\n", con_id); |
bae48da2 AC |
2018 | return desc; |
2019 | } | |
2020 | ||
2021 | status = gpiod_request(desc, con_id); | |
bae48da2 AC |
2022 | if (status < 0) |
2023 | return ERR_PTR(status); | |
2024 | ||
f625d460 | 2025 | status = gpiod_configure_flags(desc, con_id, lookupflags, flags); |
39b2bbe3 AC |
2026 | if (status < 0) { |
2027 | dev_dbg(dev, "setup of GPIO %s failed\n", con_id); | |
2028 | gpiod_put(desc); | |
2029 | return ERR_PTR(status); | |
2030 | } | |
2031 | ||
bae48da2 AC |
2032 | return desc; |
2033 | } | |
b17d1bf1 | 2034 | EXPORT_SYMBOL_GPL(gpiod_get_index); |
bae48da2 | 2035 | |
40b73183 MW |
2036 | /** |
2037 | * fwnode_get_named_gpiod - obtain a GPIO from firmware node | |
2038 | * @fwnode: handle of the firmware node | |
2039 | * @propname: name of the firmware property representing the GPIO | |
2040 | * | |
2041 | * This function can be used for drivers that get their configuration | |
2042 | * from firmware. | |
2043 | * | |
2044 | * Function properly finds the corresponding GPIO using whatever is the | |
2045 | * underlying firmware interface and then makes sure that the GPIO | |
2046 | * descriptor is requested before it is returned to the caller. | |
2047 | * | |
2048 | * In case of error an ERR_PTR() is returned. | |
2049 | */ | |
2050 | struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, | |
2051 | const char *propname) | |
2052 | { | |
2053 | struct gpio_desc *desc = ERR_PTR(-ENODEV); | |
2054 | bool active_low = false; | |
2055 | int ret; | |
2056 | ||
2057 | if (!fwnode) | |
2058 | return ERR_PTR(-EINVAL); | |
2059 | ||
2060 | if (is_of_node(fwnode)) { | |
2061 | enum of_gpio_flags flags; | |
2062 | ||
c181fb3e | 2063 | desc = of_get_named_gpiod_flags(to_of_node(fwnode), propname, 0, |
40b73183 MW |
2064 | &flags); |
2065 | if (!IS_ERR(desc)) | |
2066 | active_low = flags & OF_GPIO_ACTIVE_LOW; | |
2067 | } else if (is_acpi_node(fwnode)) { | |
2068 | struct acpi_gpio_info info; | |
2069 | ||
c181fb3e | 2070 | desc = acpi_get_gpiod_by_index(to_acpi_node(fwnode), propname, 0, |
40b73183 MW |
2071 | &info); |
2072 | if (!IS_ERR(desc)) | |
2073 | active_low = info.active_low; | |
2074 | } | |
2075 | ||
2076 | if (IS_ERR(desc)) | |
2077 | return desc; | |
2078 | ||
2079 | ret = gpiod_request(desc, NULL); | |
2080 | if (ret) | |
2081 | return ERR_PTR(ret); | |
2082 | ||
2083 | /* Only value flag can be set from both DT and ACPI is active_low */ | |
2084 | if (active_low) | |
2085 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
2086 | ||
2087 | return desc; | |
2088 | } | |
2089 | EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod); | |
2090 | ||
29a1f233 TR |
2091 | /** |
2092 | * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO | |
2093 | * function | |
2094 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
2095 | * @con_id: function within the GPIO consumer | |
2096 | * @index: index of the GPIO to obtain in the consumer | |
39b2bbe3 | 2097 | * @flags: optional GPIO initialization flags |
29a1f233 TR |
2098 | * |
2099 | * This is equivalent to gpiod_get_index(), except that when no GPIO with the | |
2100 | * specified index was assigned to the requested function it will return NULL. | |
2101 | * This is convenient for drivers that need to handle optional GPIOs. | |
2102 | */ | |
b17d1bf1 | 2103 | struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev, |
29a1f233 | 2104 | const char *con_id, |
39b2bbe3 AC |
2105 | unsigned int index, |
2106 | enum gpiod_flags flags) | |
29a1f233 TR |
2107 | { |
2108 | struct gpio_desc *desc; | |
2109 | ||
39b2bbe3 | 2110 | desc = gpiod_get_index(dev, con_id, index, flags); |
29a1f233 TR |
2111 | if (IS_ERR(desc)) { |
2112 | if (PTR_ERR(desc) == -ENOENT) | |
2113 | return NULL; | |
2114 | } | |
2115 | ||
2116 | return desc; | |
2117 | } | |
b17d1bf1 | 2118 | EXPORT_SYMBOL_GPL(gpiod_get_index_optional); |
29a1f233 | 2119 | |
f625d460 BP |
2120 | /** |
2121 | * gpiod_hog - Hog the specified GPIO desc given the provided flags | |
2122 | * @desc: gpio whose value will be assigned | |
2123 | * @name: gpio line name | |
2124 | * @lflags: gpio_lookup_flags - returned from of_find_gpio() or | |
2125 | * of_get_gpio_hog() | |
2126 | * @dflags: gpiod_flags - optional GPIO initialization flags | |
2127 | */ | |
2128 | int gpiod_hog(struct gpio_desc *desc, const char *name, | |
2129 | unsigned long lflags, enum gpiod_flags dflags) | |
2130 | { | |
2131 | struct gpio_chip *chip; | |
2132 | struct gpio_desc *local_desc; | |
2133 | int hwnum; | |
2134 | int status; | |
2135 | ||
2136 | chip = gpiod_to_chip(desc); | |
2137 | hwnum = gpio_chip_hwgpio(desc); | |
2138 | ||
2139 | local_desc = gpiochip_request_own_desc(chip, hwnum, name); | |
2140 | if (IS_ERR(local_desc)) { | |
a713890d LW |
2141 | pr_err("requesting hog GPIO %s (chip %s, offset %d) failed\n", |
2142 | name, chip->label, hwnum); | |
f625d460 BP |
2143 | return PTR_ERR(local_desc); |
2144 | } | |
2145 | ||
2146 | status = gpiod_configure_flags(desc, name, lflags, dflags); | |
2147 | if (status < 0) { | |
a713890d LW |
2148 | pr_err("setup of hog GPIO %s (chip %s, offset %d) failed\n", |
2149 | name, chip->label, hwnum); | |
f625d460 BP |
2150 | gpiochip_free_own_desc(desc); |
2151 | return status; | |
2152 | } | |
2153 | ||
2154 | /* Mark GPIO as hogged so it can be identified and removed later */ | |
2155 | set_bit(FLAG_IS_HOGGED, &desc->flags); | |
2156 | ||
2157 | pr_info("GPIO line %d (%s) hogged as %s%s\n", | |
2158 | desc_to_gpio(desc), name, | |
2159 | (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input", | |
2160 | (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? | |
2161 | (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":""); | |
2162 | ||
2163 | return 0; | |
2164 | } | |
2165 | ||
2166 | /** | |
2167 | * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog | |
2168 | * @chip: gpio chip to act on | |
2169 | * | |
2170 | * This is only used by of_gpiochip_remove to free hogged gpios | |
2171 | */ | |
2172 | static void gpiochip_free_hogs(struct gpio_chip *chip) | |
2173 | { | |
2174 | int id; | |
2175 | ||
2176 | for (id = 0; id < chip->ngpio; id++) { | |
2177 | if (test_bit(FLAG_IS_HOGGED, &chip->desc[id].flags)) | |
2178 | gpiochip_free_own_desc(&chip->desc[id]); | |
2179 | } | |
2180 | } | |
2181 | ||
66858527 RI |
2182 | /** |
2183 | * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function | |
2184 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
2185 | * @con_id: function within the GPIO consumer | |
2186 | * @flags: optional GPIO initialization flags | |
2187 | * | |
2188 | * This function acquires all the GPIOs defined under a given function. | |
2189 | * | |
2190 | * Return a struct gpio_descs containing an array of descriptors, -ENOENT if | |
2191 | * no GPIO has been assigned to the requested function, or another IS_ERR() | |
2192 | * code if an error occurred while trying to acquire the GPIOs. | |
2193 | */ | |
2194 | struct gpio_descs *__must_check gpiod_get_array(struct device *dev, | |
2195 | const char *con_id, | |
2196 | enum gpiod_flags flags) | |
2197 | { | |
2198 | struct gpio_desc *desc; | |
2199 | struct gpio_descs *descs; | |
2200 | int count; | |
2201 | ||
2202 | count = gpiod_count(dev, con_id); | |
2203 | if (count < 0) | |
2204 | return ERR_PTR(count); | |
2205 | ||
2206 | descs = kzalloc(sizeof(*descs) + sizeof(descs->desc[0]) * count, | |
2207 | GFP_KERNEL); | |
2208 | if (!descs) | |
2209 | return ERR_PTR(-ENOMEM); | |
2210 | ||
2211 | for (descs->ndescs = 0; descs->ndescs < count; ) { | |
2212 | desc = gpiod_get_index(dev, con_id, descs->ndescs, flags); | |
2213 | if (IS_ERR(desc)) { | |
2214 | gpiod_put_array(descs); | |
2215 | return ERR_CAST(desc); | |
2216 | } | |
2217 | descs->desc[descs->ndescs] = desc; | |
2218 | descs->ndescs++; | |
2219 | } | |
2220 | return descs; | |
2221 | } | |
2222 | EXPORT_SYMBOL_GPL(gpiod_get_array); | |
2223 | ||
2224 | /** | |
2225 | * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO | |
2226 | * function | |
2227 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
2228 | * @con_id: function within the GPIO consumer | |
2229 | * @flags: optional GPIO initialization flags | |
2230 | * | |
2231 | * This is equivalent to gpiod_get_array(), except that when no GPIO was | |
2232 | * assigned to the requested function it will return NULL. | |
2233 | */ | |
2234 | struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev, | |
2235 | const char *con_id, | |
2236 | enum gpiod_flags flags) | |
2237 | { | |
2238 | struct gpio_descs *descs; | |
2239 | ||
2240 | descs = gpiod_get_array(dev, con_id, flags); | |
2241 | if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT)) | |
2242 | return NULL; | |
2243 | ||
2244 | return descs; | |
2245 | } | |
2246 | EXPORT_SYMBOL_GPL(gpiod_get_array_optional); | |
2247 | ||
bae48da2 AC |
2248 | /** |
2249 | * gpiod_put - dispose of a GPIO descriptor | |
2250 | * @desc: GPIO descriptor to dispose of | |
2251 | * | |
2252 | * No descriptor can be used after gpiod_put() has been called on it. | |
2253 | */ | |
2254 | void gpiod_put(struct gpio_desc *desc) | |
2255 | { | |
2256 | gpiod_free(desc); | |
372e722e | 2257 | } |
bae48da2 | 2258 | EXPORT_SYMBOL_GPL(gpiod_put); |
d2876d08 | 2259 | |
66858527 RI |
2260 | /** |
2261 | * gpiod_put_array - dispose of multiple GPIO descriptors | |
2262 | * @descs: struct gpio_descs containing an array of descriptors | |
2263 | */ | |
2264 | void gpiod_put_array(struct gpio_descs *descs) | |
2265 | { | |
2266 | unsigned int i; | |
2267 | ||
2268 | for (i = 0; i < descs->ndescs; i++) | |
2269 | gpiod_put(descs->desc[i]); | |
2270 | ||
2271 | kfree(descs); | |
2272 | } | |
2273 | EXPORT_SYMBOL_GPL(gpiod_put_array); | |
2274 | ||
d2876d08 DB |
2275 | #ifdef CONFIG_DEBUG_FS |
2276 | ||
d2876d08 DB |
2277 | static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip) |
2278 | { | |
2279 | unsigned i; | |
2280 | unsigned gpio = chip->base; | |
6c0b4e6c | 2281 | struct gpio_desc *gdesc = &chip->desc[0]; |
d2876d08 | 2282 | int is_out; |
d468bf9e | 2283 | int is_irq; |
d2876d08 DB |
2284 | |
2285 | for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) { | |
2286 | if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) | |
2287 | continue; | |
2288 | ||
372e722e | 2289 | gpiod_get_direction(gdesc); |
d2876d08 | 2290 | is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); |
d468bf9e LW |
2291 | is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); |
2292 | seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s", | |
d2876d08 DB |
2293 | gpio, gdesc->label, |
2294 | is_out ? "out" : "in ", | |
2295 | chip->get | |
2296 | ? (chip->get(chip, i) ? "hi" : "lo") | |
d468bf9e LW |
2297 | : "? ", |
2298 | is_irq ? "IRQ" : " "); | |
d2876d08 DB |
2299 | seq_printf(s, "\n"); |
2300 | } | |
2301 | } | |
2302 | ||
f9c4a31f | 2303 | static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) |
d2876d08 | 2304 | { |
362432ae | 2305 | unsigned long flags; |
f9c4a31f | 2306 | struct gpio_chip *chip = NULL; |
cb1650d4 | 2307 | loff_t index = *pos; |
d2876d08 | 2308 | |
f9c4a31f | 2309 | s->private = ""; |
d2876d08 | 2310 | |
362432ae | 2311 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 | 2312 | list_for_each_entry(chip, &gpio_chips, list) |
362432ae GL |
2313 | if (index-- == 0) { |
2314 | spin_unlock_irqrestore(&gpio_lock, flags); | |
cb1650d4 | 2315 | return chip; |
f9c4a31f | 2316 | } |
362432ae | 2317 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f | 2318 | |
cb1650d4 | 2319 | return NULL; |
f9c4a31f TR |
2320 | } |
2321 | ||
2322 | static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
2323 | { | |
362432ae | 2324 | unsigned long flags; |
f9c4a31f | 2325 | struct gpio_chip *chip = v; |
f9c4a31f TR |
2326 | void *ret = NULL; |
2327 | ||
362432ae | 2328 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 AC |
2329 | if (list_is_last(&chip->list, &gpio_chips)) |
2330 | ret = NULL; | |
2331 | else | |
2332 | ret = list_entry(chip->list.next, struct gpio_chip, list); | |
362432ae | 2333 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f TR |
2334 | |
2335 | s->private = "\n"; | |
2336 | ++*pos; | |
2337 | ||
2338 | return ret; | |
2339 | } | |
2340 | ||
2341 | static void gpiolib_seq_stop(struct seq_file *s, void *v) | |
2342 | { | |
2343 | } | |
2344 | ||
2345 | static int gpiolib_seq_show(struct seq_file *s, void *v) | |
2346 | { | |
2347 | struct gpio_chip *chip = v; | |
2348 | struct device *dev; | |
2349 | ||
2350 | seq_printf(s, "%sGPIOs %d-%d", (char *)s->private, | |
2351 | chip->base, chip->base + chip->ngpio - 1); | |
2352 | dev = chip->dev; | |
2353 | if (dev) | |
2354 | seq_printf(s, ", %s/%s", dev->bus ? dev->bus->name : "no-bus", | |
2355 | dev_name(dev)); | |
2356 | if (chip->label) | |
2357 | seq_printf(s, ", %s", chip->label); | |
2358 | if (chip->can_sleep) | |
2359 | seq_printf(s, ", can sleep"); | |
2360 | seq_printf(s, ":\n"); | |
2361 | ||
2362 | if (chip->dbg_show) | |
2363 | chip->dbg_show(s, chip); | |
2364 | else | |
2365 | gpiolib_dbg_show(s, chip); | |
2366 | ||
d2876d08 DB |
2367 | return 0; |
2368 | } | |
2369 | ||
f9c4a31f TR |
2370 | static const struct seq_operations gpiolib_seq_ops = { |
2371 | .start = gpiolib_seq_start, | |
2372 | .next = gpiolib_seq_next, | |
2373 | .stop = gpiolib_seq_stop, | |
2374 | .show = gpiolib_seq_show, | |
2375 | }; | |
2376 | ||
d2876d08 DB |
2377 | static int gpiolib_open(struct inode *inode, struct file *file) |
2378 | { | |
f9c4a31f | 2379 | return seq_open(file, &gpiolib_seq_ops); |
d2876d08 DB |
2380 | } |
2381 | ||
828c0950 | 2382 | static const struct file_operations gpiolib_operations = { |
f9c4a31f | 2383 | .owner = THIS_MODULE, |
d2876d08 DB |
2384 | .open = gpiolib_open, |
2385 | .read = seq_read, | |
2386 | .llseek = seq_lseek, | |
f9c4a31f | 2387 | .release = seq_release, |
d2876d08 DB |
2388 | }; |
2389 | ||
2390 | static int __init gpiolib_debugfs_init(void) | |
2391 | { | |
2392 | /* /sys/kernel/debug/gpio */ | |
2393 | (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO, | |
2394 | NULL, NULL, &gpiolib_operations); | |
2395 | return 0; | |
2396 | } | |
2397 | subsys_initcall(gpiolib_debugfs_init); | |
2398 | ||
2399 | #endif /* DEBUG_FS */ |