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 | { | |
d1aceb80 | 193 | struct list_head *pos; |
1a989d0f AC |
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 | ||
28355f81 TV |
293 | status = of_gpiochip_add(chip); |
294 | if (status) | |
295 | goto err_remove_chip; | |
296 | ||
664e3e5a | 297 | acpi_gpiochip_add(chip); |
391c970c | 298 | |
426577bd | 299 | status = gpiochip_sysfs_register(chip); |
225fce83 JH |
300 | if (status) |
301 | goto err_remove_chip; | |
cedb1881 | 302 | |
7589e59f | 303 | pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__, |
64842aad GL |
304 | chip->base, chip->base + chip->ngpio - 1, |
305 | chip->label ? : "generic"); | |
306 | ||
cedb1881 | 307 | return 0; |
3bae4811 | 308 | |
225fce83 JH |
309 | err_remove_chip: |
310 | acpi_gpiochip_remove(chip); | |
6d86750c | 311 | gpiochip_free_hogs(chip); |
225fce83 JH |
312 | of_gpiochip_remove(chip); |
313 | spin_lock_irqsave(&gpio_lock, flags); | |
314 | list_del(&chip->list); | |
3bae4811 | 315 | spin_unlock_irqrestore(&gpio_lock, flags); |
05aa5203 | 316 | chip->desc = NULL; |
225fce83 | 317 | err_free_descs: |
14e85c0e | 318 | kfree(descs); |
14e85c0e | 319 | |
d2876d08 | 320 | /* failures here can mean systems won't boot... */ |
7589e59f | 321 | pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__, |
cedb1881 AV |
322 | chip->base, chip->base + chip->ngpio - 1, |
323 | chip->label ? : "generic"); | |
d2876d08 DB |
324 | return status; |
325 | } | |
326 | EXPORT_SYMBOL_GPL(gpiochip_add); | |
327 | ||
328 | /** | |
329 | * gpiochip_remove() - unregister a gpio_chip | |
330 | * @chip: the chip to unregister | |
331 | * | |
332 | * A gpio_chip with any GPIOs still requested may not be removed. | |
333 | */ | |
e1db1706 | 334 | void gpiochip_remove(struct gpio_chip *chip) |
d2876d08 | 335 | { |
fab28b89 | 336 | struct gpio_desc *desc; |
d2876d08 | 337 | unsigned long flags; |
d2876d08 | 338 | unsigned id; |
fab28b89 | 339 | bool requested = false; |
d2876d08 | 340 | |
426577bd | 341 | gpiochip_sysfs_unregister(chip); |
01cca93a | 342 | |
00acc3dc JH |
343 | gpiochip_irqchip_remove(chip); |
344 | ||
6072b9dc | 345 | acpi_gpiochip_remove(chip); |
9ef0d6f7 | 346 | gpiochip_remove_pin_ranges(chip); |
f625d460 | 347 | gpiochip_free_hogs(chip); |
391c970c AV |
348 | of_gpiochip_remove(chip); |
349 | ||
6798acaa | 350 | spin_lock_irqsave(&gpio_lock, flags); |
6c0b4e6c | 351 | for (id = 0; id < chip->ngpio; id++) { |
fab28b89 JH |
352 | desc = &chip->desc[id]; |
353 | desc->chip = NULL; | |
354 | if (test_bit(FLAG_REQUESTED, &desc->flags)) | |
355 | requested = true; | |
d2876d08 | 356 | } |
e1db1706 | 357 | list_del(&chip->list); |
d2876d08 | 358 | spin_unlock_irqrestore(&gpio_lock, flags); |
14e85c0e | 359 | |
fab28b89 JH |
360 | if (requested) |
361 | dev_crit(chip->dev, "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n"); | |
362 | ||
14e85c0e AC |
363 | kfree(chip->desc); |
364 | chip->desc = NULL; | |
d2876d08 DB |
365 | } |
366 | EXPORT_SYMBOL_GPL(gpiochip_remove); | |
367 | ||
594fa265 GL |
368 | /** |
369 | * gpiochip_find() - iterator for locating a specific gpio_chip | |
370 | * @data: data to pass to match function | |
371 | * @callback: Callback function to check gpio_chip | |
372 | * | |
373 | * Similar to bus_find_device. It returns a reference to a gpio_chip as | |
374 | * determined by a user supplied @match callback. The callback should return | |
375 | * 0 if the device doesn't match and non-zero if it does. If the callback is | |
376 | * non-zero, this function will return to the caller and not iterate over any | |
377 | * more gpio_chips. | |
378 | */ | |
07ce8ec7 | 379 | struct gpio_chip *gpiochip_find(void *data, |
6e2cf651 | 380 | int (*match)(struct gpio_chip *chip, |
3d0f7cf0 | 381 | void *data)) |
594fa265 | 382 | { |
125eef96 | 383 | struct gpio_chip *chip; |
594fa265 | 384 | unsigned long flags; |
594fa265 GL |
385 | |
386 | spin_lock_irqsave(&gpio_lock, flags); | |
125eef96 AC |
387 | list_for_each_entry(chip, &gpio_chips, list) |
388 | if (match(chip, data)) | |
594fa265 | 389 | break; |
125eef96 AC |
390 | |
391 | /* No match? */ | |
392 | if (&chip->list == &gpio_chips) | |
393 | chip = NULL; | |
594fa265 GL |
394 | spin_unlock_irqrestore(&gpio_lock, flags); |
395 | ||
396 | return chip; | |
397 | } | |
8fa0c9bf | 398 | EXPORT_SYMBOL_GPL(gpiochip_find); |
d2876d08 | 399 | |
79697ef9 AC |
400 | static int gpiochip_match_name(struct gpio_chip *chip, void *data) |
401 | { | |
402 | const char *name = data; | |
403 | ||
404 | return !strcmp(chip->label, name); | |
405 | } | |
406 | ||
407 | static struct gpio_chip *find_chip_by_name(const char *name) | |
408 | { | |
409 | return gpiochip_find((void *)name, gpiochip_match_name); | |
410 | } | |
411 | ||
14250520 LW |
412 | #ifdef CONFIG_GPIOLIB_IRQCHIP |
413 | ||
414 | /* | |
415 | * The following is irqchip helper code for gpiochips. | |
416 | */ | |
417 | ||
418 | /** | |
3f97d5fc LW |
419 | * gpiochip_set_chained_irqchip() - sets a chained irqchip to a gpiochip |
420 | * @gpiochip: the gpiochip to set the irqchip chain to | |
421 | * @irqchip: the irqchip to chain to the gpiochip | |
14250520 LW |
422 | * @parent_irq: the irq number corresponding to the parent IRQ for this |
423 | * chained irqchip | |
424 | * @parent_handler: the parent interrupt handler for the accumulated IRQ | |
3f97d5fc LW |
425 | * coming out of the gpiochip. If the interrupt is nested rather than |
426 | * cascaded, pass NULL in this handler argument | |
14250520 LW |
427 | */ |
428 | void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, | |
429 | struct irq_chip *irqchip, | |
430 | int parent_irq, | |
431 | irq_flow_handler_t parent_handler) | |
432 | { | |
83141a77 LW |
433 | unsigned int offset; |
434 | ||
83141a77 LW |
435 | if (!gpiochip->irqdomain) { |
436 | chip_err(gpiochip, "called %s before setting up irqchip\n", | |
437 | __func__); | |
1c8732bb LW |
438 | return; |
439 | } | |
440 | ||
3f97d5fc LW |
441 | if (parent_handler) { |
442 | if (gpiochip->can_sleep) { | |
443 | chip_err(gpiochip, | |
444 | "you cannot have chained interrupts on a " | |
445 | "chip that may sleep\n"); | |
446 | return; | |
447 | } | |
3f97d5fc LW |
448 | /* |
449 | * The parent irqchip is already using the chip_data for this | |
450 | * irqchip, so our callbacks simply use the handler_data. | |
451 | */ | |
f7f87753 TG |
452 | irq_set_chained_handler_and_data(parent_irq, parent_handler, |
453 | gpiochip); | |
25e4fe92 DES |
454 | |
455 | gpiochip->irq_parent = parent_irq; | |
3f97d5fc | 456 | } |
83141a77 LW |
457 | |
458 | /* Set the parent IRQ for all affected IRQs */ | |
459 | for (offset = 0; offset < gpiochip->ngpio; offset++) | |
460 | irq_set_parent(irq_find_mapping(gpiochip->irqdomain, offset), | |
461 | parent_irq); | |
14250520 LW |
462 | } |
463 | EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip); | |
464 | ||
465 | /** | |
466 | * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip | |
467 | * @d: the irqdomain used by this irqchip | |
468 | * @irq: the global irq number used by this GPIO irqchip irq | |
469 | * @hwirq: the local IRQ/GPIO line offset on this gpiochip | |
470 | * | |
471 | * This function will set up the mapping for a certain IRQ line on a | |
472 | * gpiochip by assigning the gpiochip as chip data, and using the irqchip | |
473 | * stored inside the gpiochip. | |
474 | */ | |
475 | static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, | |
476 | irq_hw_number_t hwirq) | |
477 | { | |
478 | struct gpio_chip *chip = d->host_data; | |
479 | ||
14250520 | 480 | irq_set_chip_data(irq, chip); |
a0a8bcf4 GS |
481 | /* |
482 | * This lock class tells lockdep that GPIO irqs are in a different | |
483 | * category than their parents, so it won't report false recursion. | |
484 | */ | |
485 | irq_set_lockdep_class(irq, chip->lock_key); | |
7633fb95 | 486 | irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler); |
1c8732bb | 487 | /* Chips that can sleep need nested thread handlers */ |
295494af | 488 | if (chip->can_sleep && !chip->irq_not_threaded) |
1c8732bb | 489 | irq_set_nested_thread(irq, 1); |
14250520 | 490 | irq_set_noprobe(irq); |
23393d49 | 491 | |
1333b90f LW |
492 | /* |
493 | * No set-up of the hardware will happen if IRQ_TYPE_NONE | |
494 | * is passed as default type. | |
495 | */ | |
496 | if (chip->irq_default_type != IRQ_TYPE_NONE) | |
497 | irq_set_irq_type(irq, chip->irq_default_type); | |
14250520 LW |
498 | |
499 | return 0; | |
500 | } | |
501 | ||
c3626fde LW |
502 | static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) |
503 | { | |
1c8732bb LW |
504 | struct gpio_chip *chip = d->host_data; |
505 | ||
1c8732bb LW |
506 | if (chip->can_sleep) |
507 | irq_set_nested_thread(irq, 0); | |
c3626fde LW |
508 | irq_set_chip_and_handler(irq, NULL, NULL); |
509 | irq_set_chip_data(irq, NULL); | |
510 | } | |
511 | ||
14250520 LW |
512 | static const struct irq_domain_ops gpiochip_domain_ops = { |
513 | .map = gpiochip_irq_map, | |
c3626fde | 514 | .unmap = gpiochip_irq_unmap, |
14250520 LW |
515 | /* Virtually all GPIO irqchips are twocell:ed */ |
516 | .xlate = irq_domain_xlate_twocell, | |
517 | }; | |
518 | ||
519 | static int gpiochip_irq_reqres(struct irq_data *d) | |
520 | { | |
521 | struct gpio_chip *chip = irq_data_get_irq_chip_data(d); | |
522 | ||
5b76e79c GS |
523 | if (!try_module_get(chip->owner)) |
524 | return -ENODEV; | |
525 | ||
e3a2e878 | 526 | if (gpiochip_lock_as_irq(chip, d->hwirq)) { |
14250520 LW |
527 | chip_err(chip, |
528 | "unable to lock HW IRQ %lu for IRQ\n", | |
529 | d->hwirq); | |
5b76e79c | 530 | module_put(chip->owner); |
14250520 LW |
531 | return -EINVAL; |
532 | } | |
533 | return 0; | |
534 | } | |
535 | ||
536 | static void gpiochip_irq_relres(struct irq_data *d) | |
537 | { | |
538 | struct gpio_chip *chip = irq_data_get_irq_chip_data(d); | |
539 | ||
e3a2e878 | 540 | gpiochip_unlock_as_irq(chip, d->hwirq); |
5b76e79c | 541 | module_put(chip->owner); |
14250520 LW |
542 | } |
543 | ||
544 | static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) | |
545 | { | |
546 | return irq_find_mapping(chip->irqdomain, offset); | |
547 | } | |
548 | ||
549 | /** | |
550 | * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip | |
551 | * @gpiochip: the gpiochip to remove the irqchip from | |
552 | * | |
553 | * This is called only from gpiochip_remove() | |
554 | */ | |
555 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) | |
556 | { | |
c3626fde LW |
557 | unsigned int offset; |
558 | ||
afa82fab MW |
559 | acpi_gpiochip_free_interrupts(gpiochip); |
560 | ||
25e4fe92 DES |
561 | if (gpiochip->irq_parent) { |
562 | irq_set_chained_handler(gpiochip->irq_parent, NULL); | |
563 | irq_set_handler_data(gpiochip->irq_parent, NULL); | |
564 | } | |
565 | ||
c3626fde LW |
566 | /* Remove all IRQ mappings and delete the domain */ |
567 | if (gpiochip->irqdomain) { | |
568 | for (offset = 0; offset < gpiochip->ngpio; offset++) | |
e3893386 GS |
569 | irq_dispose_mapping( |
570 | irq_find_mapping(gpiochip->irqdomain, offset)); | |
14250520 | 571 | irq_domain_remove(gpiochip->irqdomain); |
c3626fde | 572 | } |
14250520 LW |
573 | |
574 | if (gpiochip->irqchip) { | |
575 | gpiochip->irqchip->irq_request_resources = NULL; | |
576 | gpiochip->irqchip->irq_release_resources = NULL; | |
577 | gpiochip->irqchip = NULL; | |
578 | } | |
579 | } | |
580 | ||
581 | /** | |
582 | * gpiochip_irqchip_add() - adds an irqchip to a gpiochip | |
583 | * @gpiochip: the gpiochip to add the irqchip to | |
584 | * @irqchip: the irqchip to add to the gpiochip | |
585 | * @first_irq: if not dynamically assigned, the base (first) IRQ to | |
586 | * allocate gpiochip irqs from | |
587 | * @handler: the irq handler to use (often a predefined irq core function) | |
1333b90f LW |
588 | * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE |
589 | * to have the core avoid setting up any default type in the hardware. | |
a0a8bcf4 | 590 | * @lock_key: lockdep class |
14250520 LW |
591 | * |
592 | * This function closely associates a certain irqchip with a certain | |
593 | * gpiochip, providing an irq domain to translate the local IRQs to | |
594 | * global irqs in the gpiolib core, and making sure that the gpiochip | |
595 | * is passed as chip data to all related functions. Driver callbacks | |
596 | * need to use container_of() to get their local state containers back | |
597 | * from the gpiochip passed as chip data. An irqdomain will be stored | |
598 | * in the gpiochip that shall be used by the driver to handle IRQ number | |
599 | * translation. The gpiochip will need to be initialized and registered | |
600 | * before calling this function. | |
601 | * | |
c3626fde LW |
602 | * This function will handle two cell:ed simple IRQs and assumes all |
603 | * the pins on the gpiochip can generate a unique IRQ. Everything else | |
14250520 LW |
604 | * need to be open coded. |
605 | */ | |
a0a8bcf4 GS |
606 | int _gpiochip_irqchip_add(struct gpio_chip *gpiochip, |
607 | struct irq_chip *irqchip, | |
608 | unsigned int first_irq, | |
609 | irq_flow_handler_t handler, | |
610 | unsigned int type, | |
611 | struct lock_class_key *lock_key) | |
14250520 LW |
612 | { |
613 | struct device_node *of_node; | |
614 | unsigned int offset; | |
c3626fde | 615 | unsigned irq_base = 0; |
14250520 LW |
616 | |
617 | if (!gpiochip || !irqchip) | |
618 | return -EINVAL; | |
619 | ||
620 | if (!gpiochip->dev) { | |
621 | pr_err("missing gpiochip .dev parent pointer\n"); | |
622 | return -EINVAL; | |
623 | } | |
624 | of_node = gpiochip->dev->of_node; | |
625 | #ifdef CONFIG_OF_GPIO | |
626 | /* | |
20a8a968 | 627 | * If the gpiochip has an assigned OF node this takes precedence |
14250520 LW |
628 | * FIXME: get rid of this and use gpiochip->dev->of_node everywhere |
629 | */ | |
630 | if (gpiochip->of_node) | |
631 | of_node = gpiochip->of_node; | |
632 | #endif | |
633 | gpiochip->irqchip = irqchip; | |
634 | gpiochip->irq_handler = handler; | |
635 | gpiochip->irq_default_type = type; | |
636 | gpiochip->to_irq = gpiochip_to_irq; | |
a0a8bcf4 | 637 | gpiochip->lock_key = lock_key; |
14250520 LW |
638 | gpiochip->irqdomain = irq_domain_add_simple(of_node, |
639 | gpiochip->ngpio, first_irq, | |
640 | &gpiochip_domain_ops, gpiochip); | |
641 | if (!gpiochip->irqdomain) { | |
642 | gpiochip->irqchip = NULL; | |
643 | return -EINVAL; | |
644 | } | |
8b67a1f0 RV |
645 | |
646 | /* | |
647 | * It is possible for a driver to override this, but only if the | |
648 | * alternative functions are both implemented. | |
649 | */ | |
650 | if (!irqchip->irq_request_resources && | |
651 | !irqchip->irq_release_resources) { | |
652 | irqchip->irq_request_resources = gpiochip_irq_reqres; | |
653 | irqchip->irq_release_resources = gpiochip_irq_relres; | |
654 | } | |
14250520 LW |
655 | |
656 | /* | |
657 | * Prepare the mapping since the irqchip shall be orthogonal to | |
658 | * any gpiochip calls. If the first_irq was zero, this is | |
659 | * necessary to allocate descriptors for all IRQs. | |
660 | */ | |
c3626fde LW |
661 | for (offset = 0; offset < gpiochip->ngpio; offset++) { |
662 | irq_base = irq_create_mapping(gpiochip->irqdomain, offset); | |
663 | if (offset == 0) | |
664 | /* | |
665 | * Store the base into the gpiochip to be used when | |
666 | * unmapping the irqs. | |
667 | */ | |
668 | gpiochip->irq_base = irq_base; | |
669 | } | |
14250520 | 670 | |
afa82fab MW |
671 | acpi_gpiochip_request_interrupts(gpiochip); |
672 | ||
14250520 LW |
673 | return 0; |
674 | } | |
a0a8bcf4 | 675 | EXPORT_SYMBOL_GPL(_gpiochip_irqchip_add); |
14250520 LW |
676 | |
677 | #else /* CONFIG_GPIOLIB_IRQCHIP */ | |
678 | ||
679 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {} | |
680 | ||
681 | #endif /* CONFIG_GPIOLIB_IRQCHIP */ | |
682 | ||
f23f1516 | 683 | #ifdef CONFIG_PINCTRL |
165adc9c | 684 | |
586a87e6 CR |
685 | /** |
686 | * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping | |
687 | * @chip: the gpiochip to add the range for | |
d32651f6 | 688 | * @pctldev: the pin controller to map to |
586a87e6 CR |
689 | * @gpio_offset: the start offset in the current gpio_chip number space |
690 | * @pin_group: name of the pin group inside the pin controller | |
691 | */ | |
692 | int gpiochip_add_pingroup_range(struct gpio_chip *chip, | |
693 | struct pinctrl_dev *pctldev, | |
694 | unsigned int gpio_offset, const char *pin_group) | |
695 | { | |
696 | struct gpio_pin_range *pin_range; | |
697 | int ret; | |
698 | ||
699 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); | |
700 | if (!pin_range) { | |
1a2a99c6 | 701 | chip_err(chip, "failed to allocate pin ranges\n"); |
586a87e6 CR |
702 | return -ENOMEM; |
703 | } | |
704 | ||
705 | /* Use local offset as range ID */ | |
706 | pin_range->range.id = gpio_offset; | |
707 | pin_range->range.gc = chip; | |
708 | pin_range->range.name = chip->label; | |
709 | pin_range->range.base = chip->base + gpio_offset; | |
710 | pin_range->pctldev = pctldev; | |
711 | ||
712 | ret = pinctrl_get_group_pins(pctldev, pin_group, | |
713 | &pin_range->range.pins, | |
714 | &pin_range->range.npins); | |
61c6375d MN |
715 | if (ret < 0) { |
716 | kfree(pin_range); | |
586a87e6 | 717 | return ret; |
61c6375d | 718 | } |
586a87e6 CR |
719 | |
720 | pinctrl_add_gpio_range(pctldev, &pin_range->range); | |
721 | ||
1a2a99c6 AS |
722 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n", |
723 | gpio_offset, gpio_offset + pin_range->range.npins - 1, | |
586a87e6 CR |
724 | pinctrl_dev_get_devname(pctldev), pin_group); |
725 | ||
726 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
727 | ||
728 | return 0; | |
729 | } | |
730 | EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); | |
731 | ||
3f0f8670 LW |
732 | /** |
733 | * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping | |
734 | * @chip: the gpiochip to add the range for | |
735 | * @pinctrl_name: the dev_name() of the pin controller to map to | |
316511c0 LW |
736 | * @gpio_offset: the start offset in the current gpio_chip number space |
737 | * @pin_offset: the start offset in the pin controller number space | |
3f0f8670 LW |
738 | * @npins: the number of pins from the offset of each pin space (GPIO and |
739 | * pin controller) to accumulate in this range | |
740 | */ | |
1e63d7b9 | 741 | int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, |
316511c0 | 742 | unsigned int gpio_offset, unsigned int pin_offset, |
3f0f8670 | 743 | unsigned int npins) |
f23f1516 SH |
744 | { |
745 | struct gpio_pin_range *pin_range; | |
b4d4b1f0 | 746 | int ret; |
f23f1516 | 747 | |
3f0f8670 | 748 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); |
f23f1516 | 749 | if (!pin_range) { |
1a2a99c6 | 750 | chip_err(chip, "failed to allocate pin ranges\n"); |
1e63d7b9 | 751 | return -ENOMEM; |
f23f1516 SH |
752 | } |
753 | ||
3f0f8670 | 754 | /* Use local offset as range ID */ |
316511c0 | 755 | pin_range->range.id = gpio_offset; |
3f0f8670 | 756 | pin_range->range.gc = chip; |
f23f1516 | 757 | pin_range->range.name = chip->label; |
316511c0 LW |
758 | pin_range->range.base = chip->base + gpio_offset; |
759 | pin_range->range.pin_base = pin_offset; | |
f23f1516 | 760 | pin_range->range.npins = npins; |
192c369c | 761 | pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, |
f23f1516 | 762 | &pin_range->range); |
8f23ca1a | 763 | if (IS_ERR(pin_range->pctldev)) { |
b4d4b1f0 | 764 | ret = PTR_ERR(pin_range->pctldev); |
1a2a99c6 | 765 | chip_err(chip, "could not create pin range\n"); |
3f0f8670 | 766 | kfree(pin_range); |
b4d4b1f0 | 767 | return ret; |
3f0f8670 | 768 | } |
1a2a99c6 AS |
769 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n", |
770 | gpio_offset, gpio_offset + npins - 1, | |
316511c0 LW |
771 | pinctl_name, |
772 | pin_offset, pin_offset + npins - 1); | |
f23f1516 SH |
773 | |
774 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
1e63d7b9 LW |
775 | |
776 | return 0; | |
f23f1516 | 777 | } |
165adc9c | 778 | EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); |
f23f1516 | 779 | |
3f0f8670 LW |
780 | /** |
781 | * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings | |
782 | * @chip: the chip to remove all the mappings for | |
783 | */ | |
f23f1516 SH |
784 | void gpiochip_remove_pin_ranges(struct gpio_chip *chip) |
785 | { | |
786 | struct gpio_pin_range *pin_range, *tmp; | |
787 | ||
788 | list_for_each_entry_safe(pin_range, tmp, &chip->pin_ranges, node) { | |
789 | list_del(&pin_range->node); | |
790 | pinctrl_remove_gpio_range(pin_range->pctldev, | |
791 | &pin_range->range); | |
3f0f8670 | 792 | kfree(pin_range); |
f23f1516 SH |
793 | } |
794 | } | |
165adc9c LW |
795 | EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); |
796 | ||
797 | #endif /* CONFIG_PINCTRL */ | |
f23f1516 | 798 | |
d2876d08 DB |
799 | /* These "optional" allocation calls help prevent drivers from stomping |
800 | * on each other, and help provide better diagnostics in debugfs. | |
801 | * They're called even less than the "set direction" calls. | |
802 | */ | |
77c2d792 | 803 | static int __gpiod_request(struct gpio_desc *desc, const char *label) |
d2876d08 | 804 | { |
77c2d792 MW |
805 | struct gpio_chip *chip = desc->chip; |
806 | int status; | |
d2876d08 DB |
807 | unsigned long flags; |
808 | ||
bcabdef1 AC |
809 | spin_lock_irqsave(&gpio_lock, flags); |
810 | ||
d2876d08 | 811 | /* NOTE: gpio_request() can be called in early boot, |
35e8bb51 | 812 | * before IRQs are enabled, for non-sleeping (SOC) GPIOs. |
d2876d08 DB |
813 | */ |
814 | ||
815 | if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { | |
816 | desc_set_label(desc, label ? : "?"); | |
817 | status = 0; | |
438d8908 | 818 | } else { |
d2876d08 | 819 | status = -EBUSY; |
7460db56 | 820 | goto done; |
35e8bb51 DB |
821 | } |
822 | ||
823 | if (chip->request) { | |
824 | /* chip->request may sleep */ | |
825 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 826 | status = chip->request(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
827 | spin_lock_irqsave(&gpio_lock, flags); |
828 | ||
829 | if (status < 0) { | |
830 | desc_set_label(desc, NULL); | |
35e8bb51 | 831 | clear_bit(FLAG_REQUESTED, &desc->flags); |
80b0a602 | 832 | goto done; |
35e8bb51 | 833 | } |
438d8908 | 834 | } |
80b0a602 MN |
835 | if (chip->get_direction) { |
836 | /* chip->get_direction may sleep */ | |
837 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 838 | gpiod_get_direction(desc); |
80b0a602 MN |
839 | spin_lock_irqsave(&gpio_lock, flags); |
840 | } | |
77c2d792 MW |
841 | done: |
842 | spin_unlock_irqrestore(&gpio_lock, flags); | |
843 | return status; | |
844 | } | |
845 | ||
0eb4c6c2 | 846 | int gpiod_request(struct gpio_desc *desc, const char *label) |
77c2d792 MW |
847 | { |
848 | int status = -EPROBE_DEFER; | |
849 | struct gpio_chip *chip; | |
850 | ||
851 | if (!desc) { | |
852 | pr_warn("%s: invalid GPIO\n", __func__); | |
853 | return -EINVAL; | |
854 | } | |
855 | ||
856 | chip = desc->chip; | |
857 | if (!chip) | |
858 | goto done; | |
859 | ||
860 | if (try_module_get(chip->owner)) { | |
861 | status = __gpiod_request(desc, label); | |
862 | if (status < 0) | |
863 | module_put(chip->owner); | |
864 | } | |
865 | ||
d2876d08 DB |
866 | done: |
867 | if (status) | |
7589e59f | 868 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
77c2d792 | 869 | |
d2876d08 DB |
870 | return status; |
871 | } | |
372e722e | 872 | |
77c2d792 | 873 | static bool __gpiod_free(struct gpio_desc *desc) |
d2876d08 | 874 | { |
77c2d792 | 875 | bool ret = false; |
d2876d08 | 876 | unsigned long flags; |
35e8bb51 | 877 | struct gpio_chip *chip; |
d2876d08 | 878 | |
3d599d1c UKK |
879 | might_sleep(); |
880 | ||
372e722e | 881 | gpiod_unexport(desc); |
d8f388d8 | 882 | |
d2876d08 DB |
883 | spin_lock_irqsave(&gpio_lock, flags); |
884 | ||
35e8bb51 DB |
885 | chip = desc->chip; |
886 | if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { | |
887 | if (chip->free) { | |
888 | spin_unlock_irqrestore(&gpio_lock, flags); | |
9c4ba946 | 889 | might_sleep_if(chip->can_sleep); |
372e722e | 890 | chip->free(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
891 | spin_lock_irqsave(&gpio_lock, flags); |
892 | } | |
d2876d08 | 893 | desc_set_label(desc, NULL); |
07697461 | 894 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); |
35e8bb51 | 895 | clear_bit(FLAG_REQUESTED, &desc->flags); |
aca5ce14 | 896 | clear_bit(FLAG_OPEN_DRAIN, &desc->flags); |
25553ff0 | 897 | clear_bit(FLAG_OPEN_SOURCE, &desc->flags); |
f625d460 | 898 | clear_bit(FLAG_IS_HOGGED, &desc->flags); |
77c2d792 MW |
899 | ret = true; |
900 | } | |
d2876d08 DB |
901 | |
902 | spin_unlock_irqrestore(&gpio_lock, flags); | |
77c2d792 MW |
903 | return ret; |
904 | } | |
905 | ||
0eb4c6c2 | 906 | void gpiod_free(struct gpio_desc *desc) |
77c2d792 MW |
907 | { |
908 | if (desc && __gpiod_free(desc)) | |
909 | module_put(desc->chip->owner); | |
910 | else | |
911 | WARN_ON(extra_checks); | |
d2876d08 | 912 | } |
372e722e | 913 | |
d2876d08 DB |
914 | /** |
915 | * gpiochip_is_requested - return string iff signal was requested | |
916 | * @chip: controller managing the signal | |
917 | * @offset: of signal within controller's 0..(ngpio - 1) range | |
918 | * | |
919 | * Returns NULL if the GPIO is not currently requested, else a string. | |
9c8318ff AC |
920 | * The string returned is the label passed to gpio_request(); if none has been |
921 | * passed it is a meaningless, non-NULL constant. | |
d2876d08 DB |
922 | * |
923 | * This function is for use by GPIO controller drivers. The label can | |
924 | * help with diagnostics, and knowing that the signal is used as a GPIO | |
925 | * can help avoid accidentally multiplexing it to another controller. | |
926 | */ | |
927 | const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) | |
928 | { | |
6c0b4e6c | 929 | struct gpio_desc *desc; |
d2876d08 | 930 | |
6c0b4e6c | 931 | if (!GPIO_OFFSET_VALID(chip, offset)) |
d2876d08 | 932 | return NULL; |
6c0b4e6c AC |
933 | |
934 | desc = &chip->desc[offset]; | |
935 | ||
372e722e | 936 | if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) |
d2876d08 | 937 | return NULL; |
372e722e | 938 | return desc->label; |
d2876d08 DB |
939 | } |
940 | EXPORT_SYMBOL_GPL(gpiochip_is_requested); | |
941 | ||
77c2d792 MW |
942 | /** |
943 | * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor | |
944 | * @desc: GPIO descriptor to request | |
945 | * @label: label for the GPIO | |
946 | * | |
947 | * Function allows GPIO chip drivers to request and use their own GPIO | |
948 | * descriptors via gpiolib API. Difference to gpiod_request() is that this | |
949 | * function will not increase reference count of the GPIO chip module. This | |
950 | * allows the GPIO chip module to be unloaded as needed (we assume that the | |
951 | * GPIO chip driver handles freeing the GPIOs it has requested). | |
952 | */ | |
abdc08a3 AC |
953 | struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum, |
954 | const char *label) | |
77c2d792 | 955 | { |
abdc08a3 AC |
956 | struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum); |
957 | int err; | |
77c2d792 | 958 | |
abdc08a3 AC |
959 | if (IS_ERR(desc)) { |
960 | chip_err(chip, "failed to get GPIO descriptor\n"); | |
961 | return desc; | |
962 | } | |
963 | ||
964 | err = __gpiod_request(desc, label); | |
965 | if (err < 0) | |
966 | return ERR_PTR(err); | |
77c2d792 | 967 | |
abdc08a3 | 968 | return desc; |
77c2d792 | 969 | } |
f7d4ad98 | 970 | EXPORT_SYMBOL_GPL(gpiochip_request_own_desc); |
77c2d792 MW |
971 | |
972 | /** | |
973 | * gpiochip_free_own_desc - Free GPIO requested by the chip driver | |
974 | * @desc: GPIO descriptor to free | |
975 | * | |
976 | * Function frees the given GPIO requested previously with | |
977 | * gpiochip_request_own_desc(). | |
978 | */ | |
979 | void gpiochip_free_own_desc(struct gpio_desc *desc) | |
980 | { | |
981 | if (desc) | |
982 | __gpiod_free(desc); | |
983 | } | |
f7d4ad98 | 984 | EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); |
d2876d08 DB |
985 | |
986 | /* Drivers MUST set GPIO direction before making get/set calls. In | |
987 | * some cases this is done in early boot, before IRQs are enabled. | |
988 | * | |
989 | * As a rule these aren't called more than once (except for drivers | |
990 | * using the open-drain emulation idiom) so these are natural places | |
991 | * to accumulate extra debugging checks. Note that we can't (yet) | |
992 | * rely on gpio_request() having been called beforehand. | |
993 | */ | |
994 | ||
79a9becd AC |
995 | /** |
996 | * gpiod_direction_input - set the GPIO direction to input | |
997 | * @desc: GPIO to set to input | |
998 | * | |
999 | * Set the direction of the passed GPIO to input, such as gpiod_get_value() can | |
1000 | * be called safely on it. | |
1001 | * | |
1002 | * Return 0 in case of success, else an error code. | |
1003 | */ | |
1004 | int gpiod_direction_input(struct gpio_desc *desc) | |
d2876d08 | 1005 | { |
d2876d08 | 1006 | struct gpio_chip *chip; |
d2876d08 DB |
1007 | int status = -EINVAL; |
1008 | ||
be1a4b13 | 1009 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1010 | pr_warn("%s: invalid GPIO\n", __func__); |
1011 | return -EINVAL; | |
1012 | } | |
1013 | ||
be1a4b13 LW |
1014 | chip = desc->chip; |
1015 | if (!chip->get || !chip->direction_input) { | |
6424de5a MB |
1016 | gpiod_warn(desc, |
1017 | "%s: missing get() or direction_input() operations\n", | |
7589e59f | 1018 | __func__); |
be1a4b13 LW |
1019 | return -EIO; |
1020 | } | |
1021 | ||
d82da797 | 1022 | status = chip->direction_input(chip, gpio_chip_hwgpio(desc)); |
d2876d08 DB |
1023 | if (status == 0) |
1024 | clear_bit(FLAG_IS_OUT, &desc->flags); | |
3f397c21 | 1025 | |
372e722e | 1026 | trace_gpio_direction(desc_to_gpio(desc), 1, status); |
d82da797 | 1027 | |
d2876d08 DB |
1028 | return status; |
1029 | } | |
79a9becd | 1030 | EXPORT_SYMBOL_GPL(gpiod_direction_input); |
372e722e | 1031 | |
ef70bbe1 | 1032 | static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) |
d2876d08 | 1033 | { |
d2876d08 | 1034 | struct gpio_chip *chip; |
d2876d08 DB |
1035 | int status = -EINVAL; |
1036 | ||
d468bf9e LW |
1037 | /* GPIOs used for IRQs shall not be set as output */ |
1038 | if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) { | |
1039 | gpiod_err(desc, | |
1040 | "%s: tried to set a GPIO tied to an IRQ as output\n", | |
1041 | __func__); | |
1042 | return -EIO; | |
1043 | } | |
1044 | ||
aca5ce14 LD |
1045 | /* Open drain pin should not be driven to 1 */ |
1046 | if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
372e722e | 1047 | return gpiod_direction_input(desc); |
aca5ce14 | 1048 | |
25553ff0 LD |
1049 | /* Open source pin should not be driven to 0 */ |
1050 | if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
372e722e | 1051 | return gpiod_direction_input(desc); |
25553ff0 | 1052 | |
be1a4b13 LW |
1053 | chip = desc->chip; |
1054 | if (!chip->set || !chip->direction_output) { | |
6424de5a MB |
1055 | gpiod_warn(desc, |
1056 | "%s: missing set() or direction_output() operations\n", | |
1057 | __func__); | |
be1a4b13 LW |
1058 | return -EIO; |
1059 | } | |
1060 | ||
d82da797 | 1061 | status = chip->direction_output(chip, gpio_chip_hwgpio(desc), value); |
d2876d08 DB |
1062 | if (status == 0) |
1063 | set_bit(FLAG_IS_OUT, &desc->flags); | |
372e722e AC |
1064 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
1065 | trace_gpio_direction(desc_to_gpio(desc), 0, status); | |
d2876d08 DB |
1066 | return status; |
1067 | } | |
ef70bbe1 PZ |
1068 | |
1069 | /** | |
1070 | * gpiod_direction_output_raw - set the GPIO direction to output | |
1071 | * @desc: GPIO to set to output | |
1072 | * @value: initial output value of the GPIO | |
1073 | * | |
1074 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
1075 | * be called safely on it. The initial value of the output must be specified | |
1076 | * as raw value on the physical line without regard for the ACTIVE_LOW status. | |
1077 | * | |
1078 | * Return 0 in case of success, else an error code. | |
1079 | */ | |
1080 | int gpiod_direction_output_raw(struct gpio_desc *desc, int value) | |
1081 | { | |
1082 | if (!desc || !desc->chip) { | |
1083 | pr_warn("%s: invalid GPIO\n", __func__); | |
1084 | return -EINVAL; | |
1085 | } | |
1086 | return _gpiod_direction_output_raw(desc, value); | |
1087 | } | |
1088 | EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); | |
1089 | ||
1090 | /** | |
90df4fe0 | 1091 | * gpiod_direction_output - set the GPIO direction to output |
ef70bbe1 PZ |
1092 | * @desc: GPIO to set to output |
1093 | * @value: initial output value of the GPIO | |
1094 | * | |
1095 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
1096 | * be called safely on it. The initial value of the output must be specified | |
1097 | * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1098 | * account. | |
1099 | * | |
1100 | * Return 0 in case of success, else an error code. | |
1101 | */ | |
1102 | int gpiod_direction_output(struct gpio_desc *desc, int value) | |
1103 | { | |
1104 | if (!desc || !desc->chip) { | |
1105 | pr_warn("%s: invalid GPIO\n", __func__); | |
1106 | return -EINVAL; | |
1107 | } | |
1108 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1109 | value = !value; | |
1110 | return _gpiod_direction_output_raw(desc, value); | |
1111 | } | |
79a9becd | 1112 | EXPORT_SYMBOL_GPL(gpiod_direction_output); |
d2876d08 | 1113 | |
c4b5be98 | 1114 | /** |
79a9becd | 1115 | * gpiod_set_debounce - sets @debounce time for a @gpio |
c4b5be98 FB |
1116 | * @gpio: the gpio to set debounce time |
1117 | * @debounce: debounce time is microseconds | |
65d87656 LW |
1118 | * |
1119 | * returns -ENOTSUPP if the controller does not support setting | |
1120 | * debounce. | |
c4b5be98 | 1121 | */ |
79a9becd | 1122 | int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) |
c4b5be98 | 1123 | { |
c4b5be98 | 1124 | struct gpio_chip *chip; |
c4b5be98 | 1125 | |
be1a4b13 | 1126 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1127 | pr_warn("%s: invalid GPIO\n", __func__); |
1128 | return -EINVAL; | |
1129 | } | |
1130 | ||
c4b5be98 | 1131 | chip = desc->chip; |
be1a4b13 | 1132 | if (!chip->set || !chip->set_debounce) { |
6424de5a MB |
1133 | gpiod_dbg(desc, |
1134 | "%s: missing set() or set_debounce() operations\n", | |
1135 | __func__); | |
65d87656 | 1136 | return -ENOTSUPP; |
be1a4b13 LW |
1137 | } |
1138 | ||
d82da797 | 1139 | return chip->set_debounce(chip, gpio_chip_hwgpio(desc), debounce); |
c4b5be98 | 1140 | } |
79a9becd | 1141 | EXPORT_SYMBOL_GPL(gpiod_set_debounce); |
372e722e | 1142 | |
79a9becd AC |
1143 | /** |
1144 | * gpiod_is_active_low - test whether a GPIO is active-low or not | |
1145 | * @desc: the gpio descriptor to test | |
1146 | * | |
1147 | * Returns 1 if the GPIO is active-low, 0 otherwise. | |
1148 | */ | |
1149 | int gpiod_is_active_low(const struct gpio_desc *desc) | |
372e722e | 1150 | { |
79a9becd | 1151 | return test_bit(FLAG_ACTIVE_LOW, &desc->flags); |
372e722e | 1152 | } |
79a9becd | 1153 | EXPORT_SYMBOL_GPL(gpiod_is_active_low); |
d2876d08 DB |
1154 | |
1155 | /* I/O calls are only valid after configuration completed; the relevant | |
1156 | * "is this a valid GPIO" error checks should already have been done. | |
1157 | * | |
1158 | * "Get" operations are often inlinable as reading a pin value register, | |
1159 | * and masking the relevant bit in that register. | |
1160 | * | |
1161 | * When "set" operations are inlinable, they involve writing that mask to | |
1162 | * one register to set a low value, or a different register to set it high. | |
1163 | * Otherwise locking is needed, so there may be little value to inlining. | |
1164 | * | |
1165 | *------------------------------------------------------------------------ | |
1166 | * | |
1167 | * IMPORTANT!!! The hot paths -- get/set value -- assume that callers | |
1168 | * have requested the GPIO. That can include implicit requesting by | |
1169 | * a direction setting call. Marking a gpio as requested locks its chip | |
1170 | * in memory, guaranteeing that these table lookups need no more locking | |
1171 | * and that gpiochip_remove() will fail. | |
1172 | * | |
1173 | * REVISIT when debugging, consider adding some instrumentation to ensure | |
1174 | * that the GPIO was actually requested. | |
1175 | */ | |
1176 | ||
23600969 | 1177 | static bool _gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 DB |
1178 | { |
1179 | struct gpio_chip *chip; | |
23600969 | 1180 | bool value; |
372e722e | 1181 | int offset; |
d2876d08 | 1182 | |
372e722e AC |
1183 | chip = desc->chip; |
1184 | offset = gpio_chip_hwgpio(desc); | |
23600969 | 1185 | value = chip->get ? chip->get(chip, offset) : false; |
372e722e | 1186 | trace_gpio_value(desc_to_gpio(desc), 1, value); |
3f397c21 | 1187 | return value; |
d2876d08 | 1188 | } |
372e722e | 1189 | |
d2876d08 | 1190 | /** |
79a9becd AC |
1191 | * gpiod_get_raw_value() - return a gpio's raw value |
1192 | * @desc: gpio whose value will be returned | |
d2876d08 | 1193 | * |
79a9becd AC |
1194 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding |
1195 | * its ACTIVE_LOW status. | |
1196 | * | |
1197 | * This function should be called from contexts where we cannot sleep, and will | |
1198 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1199 | */ |
79a9becd | 1200 | int gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 | 1201 | { |
bcabdef1 AC |
1202 | if (!desc) |
1203 | return 0; | |
e4e449e8 | 1204 | /* Should be using gpio_get_value_cansleep() */ |
d8e0ac08 | 1205 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 1206 | return _gpiod_get_raw_value(desc); |
d2876d08 | 1207 | } |
79a9becd | 1208 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value); |
372e722e | 1209 | |
79a9becd AC |
1210 | /** |
1211 | * gpiod_get_value() - return a gpio's value | |
1212 | * @desc: gpio whose value will be returned | |
1213 | * | |
1214 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
1215 | * account. | |
1216 | * | |
1217 | * This function should be called from contexts where we cannot sleep, and will | |
1218 | * complain if the GPIO chip functions potentially sleep. | |
1219 | */ | |
1220 | int gpiod_get_value(const struct gpio_desc *desc) | |
372e722e | 1221 | { |
79a9becd AC |
1222 | int value; |
1223 | if (!desc) | |
1224 | return 0; | |
1225 | /* Should be using gpio_get_value_cansleep() */ | |
1226 | WARN_ON(desc->chip->can_sleep); | |
1227 | ||
1228 | value = _gpiod_get_raw_value(desc); | |
1229 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1230 | value = !value; | |
1231 | ||
1232 | return value; | |
372e722e | 1233 | } |
79a9becd | 1234 | EXPORT_SYMBOL_GPL(gpiod_get_value); |
d2876d08 | 1235 | |
aca5ce14 LD |
1236 | /* |
1237 | * _gpio_set_open_drain_value() - Set the open drain gpio's value. | |
79a9becd | 1238 | * @desc: gpio descriptor whose state need to be set. |
20a8a968 | 1239 | * @value: Non-zero for setting it HIGH otherwise it will set to LOW. |
aca5ce14 | 1240 | */ |
23600969 | 1241 | static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value) |
aca5ce14 LD |
1242 | { |
1243 | int err = 0; | |
372e722e AC |
1244 | struct gpio_chip *chip = desc->chip; |
1245 | int offset = gpio_chip_hwgpio(desc); | |
1246 | ||
aca5ce14 | 1247 | if (value) { |
372e722e | 1248 | err = chip->direction_input(chip, offset); |
aca5ce14 | 1249 | if (!err) |
372e722e | 1250 | clear_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 1251 | } else { |
372e722e | 1252 | err = chip->direction_output(chip, offset, 0); |
aca5ce14 | 1253 | if (!err) |
372e722e | 1254 | set_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 1255 | } |
372e722e | 1256 | trace_gpio_direction(desc_to_gpio(desc), value, err); |
aca5ce14 | 1257 | if (err < 0) |
6424de5a MB |
1258 | gpiod_err(desc, |
1259 | "%s: Error in set_value for open drain err %d\n", | |
1260 | __func__, err); | |
aca5ce14 LD |
1261 | } |
1262 | ||
25553ff0 | 1263 | /* |
79a9becd AC |
1264 | * _gpio_set_open_source_value() - Set the open source gpio's value. |
1265 | * @desc: gpio descriptor whose state need to be set. | |
20a8a968 | 1266 | * @value: Non-zero for setting it HIGH otherwise it will set to LOW. |
25553ff0 | 1267 | */ |
23600969 | 1268 | static void _gpio_set_open_source_value(struct gpio_desc *desc, bool value) |
25553ff0 LD |
1269 | { |
1270 | int err = 0; | |
372e722e AC |
1271 | struct gpio_chip *chip = desc->chip; |
1272 | int offset = gpio_chip_hwgpio(desc); | |
1273 | ||
25553ff0 | 1274 | if (value) { |
372e722e | 1275 | err = chip->direction_output(chip, offset, 1); |
25553ff0 | 1276 | if (!err) |
372e722e | 1277 | set_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 1278 | } else { |
372e722e | 1279 | err = chip->direction_input(chip, offset); |
25553ff0 | 1280 | if (!err) |
372e722e | 1281 | clear_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 1282 | } |
372e722e | 1283 | trace_gpio_direction(desc_to_gpio(desc), !value, err); |
25553ff0 | 1284 | if (err < 0) |
6424de5a MB |
1285 | gpiod_err(desc, |
1286 | "%s: Error in set_value for open source err %d\n", | |
1287 | __func__, err); | |
25553ff0 LD |
1288 | } |
1289 | ||
23600969 | 1290 | static void _gpiod_set_raw_value(struct gpio_desc *desc, bool value) |
d2876d08 DB |
1291 | { |
1292 | struct gpio_chip *chip; | |
1293 | ||
372e722e | 1294 | chip = desc->chip; |
372e722e AC |
1295 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
1296 | if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
1297 | _gpio_set_open_drain_value(desc, value); | |
1298 | else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
1299 | _gpio_set_open_source_value(desc, value); | |
aca5ce14 | 1300 | else |
372e722e AC |
1301 | chip->set(chip, gpio_chip_hwgpio(desc), value); |
1302 | } | |
1303 | ||
5f424243 RI |
1304 | /* |
1305 | * set multiple outputs on the same chip; | |
1306 | * use the chip's set_multiple function if available; | |
1307 | * otherwise set the outputs sequentially; | |
1308 | * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word | |
1309 | * defines which outputs are to be changed | |
1310 | * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word | |
1311 | * defines the values the outputs specified by mask are to be set to | |
1312 | */ | |
1313 | static void gpio_chip_set_multiple(struct gpio_chip *chip, | |
1314 | unsigned long *mask, unsigned long *bits) | |
1315 | { | |
1316 | if (chip->set_multiple) { | |
1317 | chip->set_multiple(chip, mask, bits); | |
1318 | } else { | |
1319 | int i; | |
1320 | for (i = 0; i < chip->ngpio; i++) { | |
1321 | if (mask[BIT_WORD(i)] == 0) { | |
1322 | /* no more set bits in this mask word; | |
1323 | * skip ahead to the next word */ | |
1324 | i = (BIT_WORD(i) + 1) * BITS_PER_LONG - 1; | |
1325 | continue; | |
1326 | } | |
1327 | /* set outputs if the corresponding mask bit is set */ | |
38e003f4 | 1328 | if (__test_and_clear_bit(i, mask)) |
5f424243 | 1329 | chip->set(chip, i, test_bit(i, bits)); |
5f424243 RI |
1330 | } |
1331 | } | |
1332 | } | |
1333 | ||
3fff99bc RI |
1334 | static void gpiod_set_array_value_priv(bool raw, bool can_sleep, |
1335 | unsigned int array_size, | |
1336 | struct gpio_desc **desc_array, | |
1337 | int *value_array) | |
5f424243 RI |
1338 | { |
1339 | int i = 0; | |
1340 | ||
1341 | while (i < array_size) { | |
1342 | struct gpio_chip *chip = desc_array[i]->chip; | |
1343 | unsigned long mask[BITS_TO_LONGS(chip->ngpio)]; | |
1344 | unsigned long bits[BITS_TO_LONGS(chip->ngpio)]; | |
1345 | int count = 0; | |
1346 | ||
38e003f4 | 1347 | if (!can_sleep) |
5f424243 | 1348 | WARN_ON(chip->can_sleep); |
38e003f4 | 1349 | |
5f424243 RI |
1350 | memset(mask, 0, sizeof(mask)); |
1351 | do { | |
1352 | struct gpio_desc *desc = desc_array[i]; | |
1353 | int hwgpio = gpio_chip_hwgpio(desc); | |
1354 | int value = value_array[i]; | |
1355 | ||
1356 | if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1357 | value = !value; | |
1358 | trace_gpio_value(desc_to_gpio(desc), 0, value); | |
1359 | /* | |
1360 | * collect all normal outputs belonging to the same chip | |
1361 | * open drain and open source outputs are set individually | |
1362 | */ | |
1363 | if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { | |
38e003f4 | 1364 | _gpio_set_open_drain_value(desc, value); |
5f424243 RI |
1365 | } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) { |
1366 | _gpio_set_open_source_value(desc, value); | |
1367 | } else { | |
1368 | __set_bit(hwgpio, mask); | |
38e003f4 | 1369 | if (value) |
5f424243 | 1370 | __set_bit(hwgpio, bits); |
38e003f4 | 1371 | else |
5f424243 | 1372 | __clear_bit(hwgpio, bits); |
5f424243 RI |
1373 | count++; |
1374 | } | |
1375 | i++; | |
1376 | } while ((i < array_size) && (desc_array[i]->chip == chip)); | |
1377 | /* push collected bits to outputs */ | |
38e003f4 | 1378 | if (count != 0) |
5f424243 | 1379 | gpio_chip_set_multiple(chip, mask, bits); |
5f424243 RI |
1380 | } |
1381 | } | |
1382 | ||
d2876d08 | 1383 | /** |
79a9becd AC |
1384 | * gpiod_set_raw_value() - assign a gpio's raw value |
1385 | * @desc: gpio whose value will be assigned | |
d2876d08 | 1386 | * @value: value to assign |
d2876d08 | 1387 | * |
79a9becd AC |
1388 | * Set the raw value of the GPIO, i.e. the value of its physical line without |
1389 | * regard for its ACTIVE_LOW status. | |
1390 | * | |
1391 | * This function should be called from contexts where we cannot sleep, and will | |
1392 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1393 | */ |
79a9becd | 1394 | void gpiod_set_raw_value(struct gpio_desc *desc, int value) |
372e722e | 1395 | { |
bcabdef1 AC |
1396 | if (!desc) |
1397 | return; | |
e4e449e8 | 1398 | /* Should be using gpio_set_value_cansleep() */ |
d8e0ac08 | 1399 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 1400 | _gpiod_set_raw_value(desc, value); |
d2876d08 | 1401 | } |
79a9becd | 1402 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value); |
d2876d08 DB |
1403 | |
1404 | /** | |
79a9becd AC |
1405 | * gpiod_set_value() - assign a gpio's value |
1406 | * @desc: gpio whose value will be assigned | |
1407 | * @value: value to assign | |
1408 | * | |
1409 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1410 | * account | |
d2876d08 | 1411 | * |
79a9becd AC |
1412 | * This function should be called from contexts where we cannot sleep, and will |
1413 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1414 | */ |
79a9becd | 1415 | void gpiod_set_value(struct gpio_desc *desc, int value) |
d2876d08 | 1416 | { |
bcabdef1 | 1417 | if (!desc) |
79a9becd AC |
1418 | return; |
1419 | /* Should be using gpio_set_value_cansleep() */ | |
1420 | WARN_ON(desc->chip->can_sleep); | |
1421 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1422 | value = !value; | |
1423 | _gpiod_set_raw_value(desc, value); | |
372e722e | 1424 | } |
79a9becd | 1425 | EXPORT_SYMBOL_GPL(gpiod_set_value); |
d2876d08 | 1426 | |
5f424243 | 1427 | /** |
3fff99bc | 1428 | * gpiod_set_raw_array_value() - assign values to an array of GPIOs |
5f424243 RI |
1429 | * @array_size: number of elements in the descriptor / value arrays |
1430 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1431 | * @value_array: array of values to assign | |
1432 | * | |
1433 | * Set the raw values of the GPIOs, i.e. the values of the physical lines | |
1434 | * without regard for their ACTIVE_LOW status. | |
1435 | * | |
1436 | * This function should be called from contexts where we cannot sleep, and will | |
1437 | * complain if the GPIO chip functions potentially sleep. | |
1438 | */ | |
3fff99bc | 1439 | void gpiod_set_raw_array_value(unsigned int array_size, |
5f424243 RI |
1440 | struct gpio_desc **desc_array, int *value_array) |
1441 | { | |
1442 | if (!desc_array) | |
1443 | return; | |
3fff99bc RI |
1444 | gpiod_set_array_value_priv(true, false, array_size, desc_array, |
1445 | value_array); | |
5f424243 | 1446 | } |
3fff99bc | 1447 | EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value); |
5f424243 RI |
1448 | |
1449 | /** | |
3fff99bc | 1450 | * gpiod_set_array_value() - assign values to an array of GPIOs |
5f424243 RI |
1451 | * @array_size: number of elements in the descriptor / value arrays |
1452 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1453 | * @value_array: array of values to assign | |
1454 | * | |
1455 | * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status | |
1456 | * into account. | |
1457 | * | |
1458 | * This function should be called from contexts where we cannot sleep, and will | |
1459 | * complain if the GPIO chip functions potentially sleep. | |
1460 | */ | |
3fff99bc RI |
1461 | void gpiod_set_array_value(unsigned int array_size, |
1462 | struct gpio_desc **desc_array, int *value_array) | |
5f424243 RI |
1463 | { |
1464 | if (!desc_array) | |
1465 | return; | |
3fff99bc RI |
1466 | gpiod_set_array_value_priv(false, false, array_size, desc_array, |
1467 | value_array); | |
5f424243 | 1468 | } |
3fff99bc | 1469 | EXPORT_SYMBOL_GPL(gpiod_set_array_value); |
5f424243 | 1470 | |
d2876d08 | 1471 | /** |
79a9becd AC |
1472 | * gpiod_cansleep() - report whether gpio value access may sleep |
1473 | * @desc: gpio to check | |
d2876d08 | 1474 | * |
d2876d08 | 1475 | */ |
79a9becd | 1476 | int gpiod_cansleep(const struct gpio_desc *desc) |
372e722e | 1477 | { |
bcabdef1 AC |
1478 | if (!desc) |
1479 | return 0; | |
372e722e | 1480 | return desc->chip->can_sleep; |
d2876d08 | 1481 | } |
79a9becd | 1482 | EXPORT_SYMBOL_GPL(gpiod_cansleep); |
d2876d08 | 1483 | |
0f6d504e | 1484 | /** |
79a9becd AC |
1485 | * gpiod_to_irq() - return the IRQ corresponding to a GPIO |
1486 | * @desc: gpio whose IRQ will be returned (already requested) | |
0f6d504e | 1487 | * |
79a9becd AC |
1488 | * Return the IRQ corresponding to the passed GPIO, or an error code in case of |
1489 | * error. | |
0f6d504e | 1490 | */ |
79a9becd | 1491 | int gpiod_to_irq(const struct gpio_desc *desc) |
0f6d504e DB |
1492 | { |
1493 | struct gpio_chip *chip; | |
372e722e | 1494 | int offset; |
0f6d504e | 1495 | |
bcabdef1 AC |
1496 | if (!desc) |
1497 | return -EINVAL; | |
372e722e AC |
1498 | chip = desc->chip; |
1499 | offset = gpio_chip_hwgpio(desc); | |
1500 | return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO; | |
0f6d504e | 1501 | } |
79a9becd | 1502 | EXPORT_SYMBOL_GPL(gpiod_to_irq); |
0f6d504e | 1503 | |
d468bf9e | 1504 | /** |
e3a2e878 | 1505 | * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ |
d74be6df AC |
1506 | * @chip: the chip the GPIO to lock belongs to |
1507 | * @offset: the offset of the GPIO to lock as IRQ | |
d468bf9e LW |
1508 | * |
1509 | * This is used directly by GPIO drivers that want to lock down | |
f438acdf | 1510 | * a certain GPIO line to be used for IRQs. |
d468bf9e | 1511 | */ |
e3a2e878 | 1512 | int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset) |
372e722e | 1513 | { |
d74be6df | 1514 | if (offset >= chip->ngpio) |
d468bf9e LW |
1515 | return -EINVAL; |
1516 | ||
d74be6df AC |
1517 | if (test_bit(FLAG_IS_OUT, &chip->desc[offset].flags)) { |
1518 | chip_err(chip, | |
d468bf9e LW |
1519 | "%s: tried to flag a GPIO set as output for IRQ\n", |
1520 | __func__); | |
1521 | return -EIO; | |
1522 | } | |
1523 | ||
d74be6df | 1524 | set_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags); |
d468bf9e | 1525 | return 0; |
372e722e | 1526 | } |
e3a2e878 | 1527 | EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq); |
d2876d08 | 1528 | |
d468bf9e | 1529 | /** |
e3a2e878 | 1530 | * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ |
d74be6df AC |
1531 | * @chip: the chip the GPIO to lock belongs to |
1532 | * @offset: the offset of the GPIO to lock as IRQ | |
d468bf9e LW |
1533 | * |
1534 | * This is used directly by GPIO drivers that want to indicate | |
1535 | * that a certain GPIO is no longer used exclusively for IRQ. | |
d2876d08 | 1536 | */ |
e3a2e878 | 1537 | void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) |
d468bf9e | 1538 | { |
d74be6df | 1539 | if (offset >= chip->ngpio) |
d468bf9e | 1540 | return; |
d2876d08 | 1541 | |
d74be6df | 1542 | clear_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags); |
d468bf9e | 1543 | } |
e3a2e878 | 1544 | EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq); |
d468bf9e | 1545 | |
79a9becd AC |
1546 | /** |
1547 | * gpiod_get_raw_value_cansleep() - return a gpio's raw value | |
1548 | * @desc: gpio whose value will be returned | |
1549 | * | |
1550 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding | |
1551 | * its ACTIVE_LOW status. | |
1552 | * | |
1553 | * This function is to be called from contexts that can sleep. | |
d2876d08 | 1554 | */ |
79a9becd | 1555 | int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) |
d2876d08 | 1556 | { |
d2876d08 | 1557 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1558 | if (!desc) |
1559 | return 0; | |
79a9becd | 1560 | return _gpiod_get_raw_value(desc); |
d2876d08 | 1561 | } |
79a9becd | 1562 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); |
372e722e | 1563 | |
79a9becd AC |
1564 | /** |
1565 | * gpiod_get_value_cansleep() - return a gpio's value | |
1566 | * @desc: gpio whose value will be returned | |
1567 | * | |
1568 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
1569 | * account. | |
1570 | * | |
1571 | * This function is to be called from contexts that can sleep. | |
1572 | */ | |
1573 | int gpiod_get_value_cansleep(const struct gpio_desc *desc) | |
d2876d08 | 1574 | { |
3f397c21 | 1575 | int value; |
d2876d08 DB |
1576 | |
1577 | might_sleep_if(extra_checks); | |
bcabdef1 AC |
1578 | if (!desc) |
1579 | return 0; | |
79a9becd AC |
1580 | |
1581 | value = _gpiod_get_raw_value(desc); | |
1582 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1583 | value = !value; | |
1584 | ||
3f397c21 | 1585 | return value; |
d2876d08 | 1586 | } |
79a9becd | 1587 | EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); |
372e722e | 1588 | |
79a9becd AC |
1589 | /** |
1590 | * gpiod_set_raw_value_cansleep() - assign a gpio's raw value | |
1591 | * @desc: gpio whose value will be assigned | |
1592 | * @value: value to assign | |
1593 | * | |
1594 | * Set the raw value of the GPIO, i.e. the value of its physical line without | |
1595 | * regard for its ACTIVE_LOW status. | |
1596 | * | |
1597 | * This function is to be called from contexts that can sleep. | |
1598 | */ | |
1599 | void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) | |
372e722e | 1600 | { |
d2876d08 | 1601 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1602 | if (!desc) |
1603 | return; | |
79a9becd | 1604 | _gpiod_set_raw_value(desc, value); |
372e722e | 1605 | } |
79a9becd | 1606 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); |
d2876d08 | 1607 | |
79a9becd AC |
1608 | /** |
1609 | * gpiod_set_value_cansleep() - assign a gpio's value | |
1610 | * @desc: gpio whose value will be assigned | |
1611 | * @value: value to assign | |
1612 | * | |
1613 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1614 | * account | |
1615 | * | |
1616 | * This function is to be called from contexts that can sleep. | |
1617 | */ | |
1618 | void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) | |
d2876d08 | 1619 | { |
d2876d08 | 1620 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1621 | if (!desc) |
1622 | return; | |
79a9becd AC |
1623 | |
1624 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1625 | value = !value; | |
1626 | _gpiod_set_raw_value(desc, value); | |
372e722e | 1627 | } |
79a9becd | 1628 | EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); |
d2876d08 | 1629 | |
5f424243 | 1630 | /** |
3fff99bc | 1631 | * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs |
5f424243 RI |
1632 | * @array_size: number of elements in the descriptor / value arrays |
1633 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1634 | * @value_array: array of values to assign | |
1635 | * | |
1636 | * Set the raw values of the GPIOs, i.e. the values of the physical lines | |
1637 | * without regard for their ACTIVE_LOW status. | |
1638 | * | |
1639 | * This function is to be called from contexts that can sleep. | |
1640 | */ | |
3fff99bc RI |
1641 | void gpiod_set_raw_array_value_cansleep(unsigned int array_size, |
1642 | struct gpio_desc **desc_array, | |
1643 | int *value_array) | |
5f424243 RI |
1644 | { |
1645 | might_sleep_if(extra_checks); | |
1646 | if (!desc_array) | |
1647 | return; | |
3fff99bc RI |
1648 | gpiod_set_array_value_priv(true, true, array_size, desc_array, |
1649 | value_array); | |
5f424243 | 1650 | } |
3fff99bc | 1651 | EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep); |
5f424243 RI |
1652 | |
1653 | /** | |
3fff99bc | 1654 | * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs |
5f424243 RI |
1655 | * @array_size: number of elements in the descriptor / value arrays |
1656 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1657 | * @value_array: array of values to assign | |
1658 | * | |
1659 | * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status | |
1660 | * into account. | |
1661 | * | |
1662 | * This function is to be called from contexts that can sleep. | |
1663 | */ | |
3fff99bc RI |
1664 | void gpiod_set_array_value_cansleep(unsigned int array_size, |
1665 | struct gpio_desc **desc_array, | |
1666 | int *value_array) | |
5f424243 RI |
1667 | { |
1668 | might_sleep_if(extra_checks); | |
1669 | if (!desc_array) | |
1670 | return; | |
3fff99bc RI |
1671 | gpiod_set_array_value_priv(false, true, array_size, desc_array, |
1672 | value_array); | |
5f424243 | 1673 | } |
3fff99bc | 1674 | EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep); |
5f424243 | 1675 | |
bae48da2 | 1676 | /** |
ad824783 AC |
1677 | * gpiod_add_lookup_table() - register GPIO device consumers |
1678 | * @table: table of consumers to register | |
bae48da2 | 1679 | */ |
ad824783 | 1680 | void gpiod_add_lookup_table(struct gpiod_lookup_table *table) |
bae48da2 AC |
1681 | { |
1682 | mutex_lock(&gpio_lookup_lock); | |
1683 | ||
ad824783 | 1684 | list_add_tail(&table->list, &gpio_lookup_list); |
bae48da2 AC |
1685 | |
1686 | mutex_unlock(&gpio_lookup_lock); | |
1687 | } | |
1688 | ||
be9015ab SK |
1689 | /** |
1690 | * gpiod_remove_lookup_table() - unregister GPIO device consumers | |
1691 | * @table: table of consumers to unregister | |
1692 | */ | |
1693 | void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) | |
1694 | { | |
1695 | mutex_lock(&gpio_lookup_lock); | |
1696 | ||
1697 | list_del(&table->list); | |
1698 | ||
1699 | mutex_unlock(&gpio_lookup_lock); | |
1700 | } | |
1701 | ||
bae48da2 | 1702 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, |
53e7cac3 AC |
1703 | unsigned int idx, |
1704 | enum gpio_lookup_flags *flags) | |
bae48da2 AC |
1705 | { |
1706 | char prop_name[32]; /* 32 is max size of property name */ | |
1707 | enum of_gpio_flags of_flags; | |
1708 | struct gpio_desc *desc; | |
dd34c37a | 1709 | unsigned int i; |
bae48da2 | 1710 | |
7f2e553a | 1711 | for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { |
dd34c37a | 1712 | if (con_id) |
9e089246 | 1713 | snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id, |
7f2e553a | 1714 | gpio_suffixes[i]); |
dd34c37a | 1715 | else |
9e089246 | 1716 | snprintf(prop_name, sizeof(prop_name), "%s", |
7f2e553a | 1717 | gpio_suffixes[i]); |
bae48da2 | 1718 | |
dd34c37a TR |
1719 | desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx, |
1720 | &of_flags); | |
06fc3b70 | 1721 | if (!IS_ERR(desc) || (PTR_ERR(desc) == -EPROBE_DEFER)) |
dd34c37a TR |
1722 | break; |
1723 | } | |
bae48da2 AC |
1724 | |
1725 | if (IS_ERR(desc)) | |
1726 | return desc; | |
1727 | ||
1728 | if (of_flags & OF_GPIO_ACTIVE_LOW) | |
53e7cac3 | 1729 | *flags |= GPIO_ACTIVE_LOW; |
bae48da2 AC |
1730 | |
1731 | return desc; | |
1732 | } | |
d2876d08 | 1733 | |
81f59e9d | 1734 | static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id, |
53e7cac3 AC |
1735 | unsigned int idx, |
1736 | enum gpio_lookup_flags *flags) | |
372e722e | 1737 | { |
0d9a693c | 1738 | struct acpi_device *adev = ACPI_COMPANION(dev); |
e01f440a MW |
1739 | struct acpi_gpio_info info; |
1740 | struct gpio_desc *desc; | |
0d9a693c MW |
1741 | char propname[32]; |
1742 | int i; | |
e01f440a | 1743 | |
0d9a693c | 1744 | /* Try first from _DSD */ |
7f2e553a | 1745 | for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { |
0d9a693c MW |
1746 | if (con_id && strcmp(con_id, "gpios")) { |
1747 | snprintf(propname, sizeof(propname), "%s-%s", | |
7f2e553a | 1748 | con_id, gpio_suffixes[i]); |
0d9a693c MW |
1749 | } else { |
1750 | snprintf(propname, sizeof(propname), "%s", | |
7f2e553a | 1751 | gpio_suffixes[i]); |
0d9a693c MW |
1752 | } |
1753 | ||
1754 | desc = acpi_get_gpiod_by_index(adev, propname, idx, &info); | |
1755 | if (!IS_ERR(desc) || (PTR_ERR(desc) == -EPROBE_DEFER)) | |
1756 | break; | |
1757 | } | |
1758 | ||
1759 | /* Then from plain _CRS GPIOs */ | |
1760 | if (IS_ERR(desc)) { | |
1761 | desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info); | |
1762 | if (IS_ERR(desc)) | |
1763 | return desc; | |
1764 | } | |
e01f440a | 1765 | |
0d9a693c | 1766 | if (info.active_low) |
53e7cac3 | 1767 | *flags |= GPIO_ACTIVE_LOW; |
e01f440a MW |
1768 | |
1769 | return desc; | |
81f59e9d MW |
1770 | } |
1771 | ||
ad824783 | 1772 | static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) |
bae48da2 AC |
1773 | { |
1774 | const char *dev_id = dev ? dev_name(dev) : NULL; | |
ad824783 | 1775 | struct gpiod_lookup_table *table; |
bae48da2 AC |
1776 | |
1777 | mutex_lock(&gpio_lookup_lock); | |
1778 | ||
ad824783 AC |
1779 | list_for_each_entry(table, &gpio_lookup_list, list) { |
1780 | if (table->dev_id && dev_id) { | |
1781 | /* | |
1782 | * Valid strings on both ends, must be identical to have | |
1783 | * a match | |
1784 | */ | |
1785 | if (!strcmp(table->dev_id, dev_id)) | |
1786 | goto found; | |
1787 | } else { | |
1788 | /* | |
1789 | * One of the pointers is NULL, so both must be to have | |
1790 | * a match | |
1791 | */ | |
1792 | if (dev_id == table->dev_id) | |
1793 | goto found; | |
1794 | } | |
1795 | } | |
1796 | table = NULL; | |
bae48da2 | 1797 | |
ad824783 AC |
1798 | found: |
1799 | mutex_unlock(&gpio_lookup_lock); | |
1800 | return table; | |
1801 | } | |
bae48da2 | 1802 | |
ad824783 AC |
1803 | static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, |
1804 | unsigned int idx, | |
1805 | enum gpio_lookup_flags *flags) | |
1806 | { | |
2a3cf6a3 | 1807 | struct gpio_desc *desc = ERR_PTR(-ENOENT); |
ad824783 AC |
1808 | struct gpiod_lookup_table *table; |
1809 | struct gpiod_lookup *p; | |
bae48da2 | 1810 | |
ad824783 AC |
1811 | table = gpiod_find_lookup_table(dev); |
1812 | if (!table) | |
1813 | return desc; | |
bae48da2 | 1814 | |
ad824783 AC |
1815 | for (p = &table->table[0]; p->chip_label; p++) { |
1816 | struct gpio_chip *chip; | |
bae48da2 | 1817 | |
ad824783 | 1818 | /* idx must always match exactly */ |
bae48da2 AC |
1819 | if (p->idx != idx) |
1820 | continue; | |
1821 | ||
ad824783 AC |
1822 | /* If the lookup entry has a con_id, require exact match */ |
1823 | if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) | |
1824 | continue; | |
bae48da2 | 1825 | |
ad824783 | 1826 | chip = find_chip_by_name(p->chip_label); |
bae48da2 | 1827 | |
ad824783 | 1828 | if (!chip) { |
2a3cf6a3 AC |
1829 | dev_err(dev, "cannot find GPIO chip %s\n", |
1830 | p->chip_label); | |
1831 | return ERR_PTR(-ENODEV); | |
ad824783 | 1832 | } |
bae48da2 | 1833 | |
ad824783 | 1834 | if (chip->ngpio <= p->chip_hwnum) { |
2a3cf6a3 AC |
1835 | dev_err(dev, |
1836 | "requested GPIO %d is out of range [0..%d] for chip %s\n", | |
1837 | idx, chip->ngpio, chip->label); | |
1838 | return ERR_PTR(-EINVAL); | |
bae48da2 | 1839 | } |
bae48da2 | 1840 | |
bb1e88cc | 1841 | desc = gpiochip_get_desc(chip, p->chip_hwnum); |
ad824783 | 1842 | *flags = p->flags; |
bae48da2 | 1843 | |
2a3cf6a3 | 1844 | return desc; |
bae48da2 AC |
1845 | } |
1846 | ||
bae48da2 AC |
1847 | return desc; |
1848 | } | |
1849 | ||
66858527 RI |
1850 | static int dt_gpio_count(struct device *dev, const char *con_id) |
1851 | { | |
1852 | int ret; | |
1853 | char propname[32]; | |
1854 | unsigned int i; | |
1855 | ||
1856 | for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { | |
1857 | if (con_id) | |
1858 | snprintf(propname, sizeof(propname), "%s-%s", | |
1859 | con_id, gpio_suffixes[i]); | |
1860 | else | |
1861 | snprintf(propname, sizeof(propname), "%s", | |
1862 | gpio_suffixes[i]); | |
1863 | ||
1864 | ret = of_gpio_named_count(dev->of_node, propname); | |
1865 | if (ret >= 0) | |
1866 | break; | |
1867 | } | |
1868 | return ret; | |
1869 | } | |
1870 | ||
1871 | static int platform_gpio_count(struct device *dev, const char *con_id) | |
1872 | { | |
1873 | struct gpiod_lookup_table *table; | |
1874 | struct gpiod_lookup *p; | |
1875 | unsigned int count = 0; | |
1876 | ||
1877 | table = gpiod_find_lookup_table(dev); | |
1878 | if (!table) | |
1879 | return -ENOENT; | |
1880 | ||
1881 | for (p = &table->table[0]; p->chip_label; p++) { | |
1882 | if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) || | |
1883 | (!con_id && !p->con_id)) | |
1884 | count++; | |
1885 | } | |
1886 | if (!count) | |
1887 | return -ENOENT; | |
1888 | ||
1889 | return count; | |
1890 | } | |
1891 | ||
1892 | /** | |
1893 | * gpiod_count - return the number of GPIOs associated with a device / function | |
1894 | * or -ENOENT if no GPIO has been assigned to the requested function | |
1895 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
1896 | * @con_id: function within the GPIO consumer | |
1897 | */ | |
1898 | int gpiod_count(struct device *dev, const char *con_id) | |
1899 | { | |
1900 | int count = -ENOENT; | |
1901 | ||
1902 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) | |
1903 | count = dt_gpio_count(dev, con_id); | |
1904 | else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) | |
1905 | count = acpi_gpio_count(dev, con_id); | |
1906 | ||
1907 | if (count < 0) | |
1908 | count = platform_gpio_count(dev, con_id); | |
1909 | ||
1910 | return count; | |
1911 | } | |
1912 | EXPORT_SYMBOL_GPL(gpiod_count); | |
1913 | ||
bae48da2 | 1914 | /** |
0879162f | 1915 | * gpiod_get - obtain a GPIO for a given GPIO function |
ad824783 | 1916 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 | 1917 | * @con_id: function within the GPIO consumer |
39b2bbe3 | 1918 | * @flags: optional GPIO initialization flags |
bae48da2 AC |
1919 | * |
1920 | * Return the GPIO descriptor corresponding to the function con_id of device | |
2a3cf6a3 | 1921 | * dev, -ENOENT if no GPIO has been assigned to the requested function, or |
20a8a968 | 1922 | * another IS_ERR() code if an error occurred while trying to acquire the GPIO. |
bae48da2 | 1923 | */ |
b17d1bf1 | 1924 | struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id, |
39b2bbe3 | 1925 | enum gpiod_flags flags) |
bae48da2 | 1926 | { |
39b2bbe3 | 1927 | return gpiod_get_index(dev, con_id, 0, flags); |
bae48da2 | 1928 | } |
b17d1bf1 | 1929 | EXPORT_SYMBOL_GPL(gpiod_get); |
bae48da2 | 1930 | |
29a1f233 TR |
1931 | /** |
1932 | * gpiod_get_optional - obtain an optional GPIO for a given GPIO function | |
1933 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
1934 | * @con_id: function within the GPIO consumer | |
39b2bbe3 | 1935 | * @flags: optional GPIO initialization flags |
29a1f233 TR |
1936 | * |
1937 | * This is equivalent to gpiod_get(), except that when no GPIO was assigned to | |
1938 | * the requested function it will return NULL. This is convenient for drivers | |
1939 | * that need to handle optional GPIOs. | |
1940 | */ | |
b17d1bf1 | 1941 | struct gpio_desc *__must_check gpiod_get_optional(struct device *dev, |
39b2bbe3 AC |
1942 | const char *con_id, |
1943 | enum gpiod_flags flags) | |
29a1f233 | 1944 | { |
39b2bbe3 | 1945 | return gpiod_get_index_optional(dev, con_id, 0, flags); |
29a1f233 | 1946 | } |
b17d1bf1 | 1947 | EXPORT_SYMBOL_GPL(gpiod_get_optional); |
29a1f233 | 1948 | |
f625d460 BP |
1949 | |
1950 | /** | |
1951 | * gpiod_configure_flags - helper function to configure a given GPIO | |
1952 | * @desc: gpio whose value will be assigned | |
1953 | * @con_id: function within the GPIO consumer | |
1954 | * @lflags: gpio_lookup_flags - returned from of_find_gpio() or | |
1955 | * of_get_gpio_hog() | |
1956 | * @dflags: gpiod_flags - optional GPIO initialization flags | |
1957 | * | |
1958 | * Return 0 on success, -ENOENT if no GPIO has been assigned to the | |
1959 | * requested function and/or index, or another IS_ERR() code if an error | |
1960 | * occurred while trying to acquire the GPIO. | |
1961 | */ | |
1962 | static int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, | |
1963 | unsigned long lflags, enum gpiod_flags dflags) | |
1964 | { | |
1965 | int status; | |
1966 | ||
1967 | if (lflags & GPIO_ACTIVE_LOW) | |
1968 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
1969 | if (lflags & GPIO_OPEN_DRAIN) | |
1970 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); | |
1971 | if (lflags & GPIO_OPEN_SOURCE) | |
1972 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); | |
1973 | ||
1974 | /* No particular flag request, return here... */ | |
1975 | if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) { | |
1976 | pr_debug("no flags found for %s\n", con_id); | |
1977 | return 0; | |
1978 | } | |
1979 | ||
1980 | /* Process flags */ | |
1981 | if (dflags & GPIOD_FLAGS_BIT_DIR_OUT) | |
1982 | status = gpiod_direction_output(desc, | |
1983 | dflags & GPIOD_FLAGS_BIT_DIR_VAL); | |
1984 | else | |
1985 | status = gpiod_direction_input(desc); | |
1986 | ||
1987 | return status; | |
1988 | } | |
1989 | ||
bae48da2 AC |
1990 | /** |
1991 | * gpiod_get_index - obtain a GPIO from a multi-index GPIO function | |
fdd6a5fe | 1992 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 AC |
1993 | * @con_id: function within the GPIO consumer |
1994 | * @idx: index of the GPIO to obtain in the consumer | |
39b2bbe3 | 1995 | * @flags: optional GPIO initialization flags |
bae48da2 AC |
1996 | * |
1997 | * This variant of gpiod_get() allows to access GPIOs other than the first | |
1998 | * defined one for functions that define several GPIOs. | |
1999 | * | |
2a3cf6a3 AC |
2000 | * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the |
2001 | * requested function and/or index, or another IS_ERR() code if an error | |
20a8a968 | 2002 | * occurred while trying to acquire the GPIO. |
bae48da2 | 2003 | */ |
b17d1bf1 | 2004 | struct gpio_desc *__must_check gpiod_get_index(struct device *dev, |
bae48da2 | 2005 | const char *con_id, |
39b2bbe3 AC |
2006 | unsigned int idx, |
2007 | enum gpiod_flags flags) | |
bae48da2 | 2008 | { |
35c5d7fd | 2009 | struct gpio_desc *desc = NULL; |
bae48da2 | 2010 | int status; |
39b2bbe3 | 2011 | enum gpio_lookup_flags lookupflags = 0; |
bae48da2 AC |
2012 | |
2013 | dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); | |
2014 | ||
4d8440b9 RW |
2015 | if (dev) { |
2016 | /* Using device tree? */ | |
2017 | if (IS_ENABLED(CONFIG_OF) && dev->of_node) { | |
2018 | dev_dbg(dev, "using device tree for GPIO lookup\n"); | |
2019 | desc = of_find_gpio(dev, con_id, idx, &lookupflags); | |
2020 | } else if (ACPI_COMPANION(dev)) { | |
2021 | dev_dbg(dev, "using ACPI for GPIO lookup\n"); | |
2022 | desc = acpi_find_gpio(dev, con_id, idx, &lookupflags); | |
2023 | } | |
35c5d7fd AC |
2024 | } |
2025 | ||
2026 | /* | |
2027 | * Either we are not using DT or ACPI, or their lookup did not return | |
2028 | * a result. In that case, use platform lookup as a fallback. | |
2029 | */ | |
2a3cf6a3 | 2030 | if (!desc || desc == ERR_PTR(-ENOENT)) { |
43a8785a | 2031 | dev_dbg(dev, "using lookup tables for GPIO lookup\n"); |
39b2bbe3 | 2032 | desc = gpiod_find(dev, con_id, idx, &lookupflags); |
bae48da2 AC |
2033 | } |
2034 | ||
2035 | if (IS_ERR(desc)) { | |
351cfe0f | 2036 | dev_dbg(dev, "lookup for GPIO %s failed\n", con_id); |
bae48da2 AC |
2037 | return desc; |
2038 | } | |
2039 | ||
2040 | status = gpiod_request(desc, con_id); | |
bae48da2 AC |
2041 | if (status < 0) |
2042 | return ERR_PTR(status); | |
2043 | ||
f625d460 | 2044 | status = gpiod_configure_flags(desc, con_id, lookupflags, flags); |
39b2bbe3 AC |
2045 | if (status < 0) { |
2046 | dev_dbg(dev, "setup of GPIO %s failed\n", con_id); | |
2047 | gpiod_put(desc); | |
2048 | return ERR_PTR(status); | |
2049 | } | |
2050 | ||
bae48da2 AC |
2051 | return desc; |
2052 | } | |
b17d1bf1 | 2053 | EXPORT_SYMBOL_GPL(gpiod_get_index); |
bae48da2 | 2054 | |
40b73183 MW |
2055 | /** |
2056 | * fwnode_get_named_gpiod - obtain a GPIO from firmware node | |
2057 | * @fwnode: handle of the firmware node | |
2058 | * @propname: name of the firmware property representing the GPIO | |
2059 | * | |
2060 | * This function can be used for drivers that get their configuration | |
2061 | * from firmware. | |
2062 | * | |
2063 | * Function properly finds the corresponding GPIO using whatever is the | |
2064 | * underlying firmware interface and then makes sure that the GPIO | |
2065 | * descriptor is requested before it is returned to the caller. | |
2066 | * | |
2067 | * In case of error an ERR_PTR() is returned. | |
2068 | */ | |
2069 | struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, | |
2070 | const char *propname) | |
2071 | { | |
2072 | struct gpio_desc *desc = ERR_PTR(-ENODEV); | |
2073 | bool active_low = false; | |
2074 | int ret; | |
2075 | ||
2076 | if (!fwnode) | |
2077 | return ERR_PTR(-EINVAL); | |
2078 | ||
2079 | if (is_of_node(fwnode)) { | |
2080 | enum of_gpio_flags flags; | |
2081 | ||
c181fb3e | 2082 | desc = of_get_named_gpiod_flags(to_of_node(fwnode), propname, 0, |
40b73183 MW |
2083 | &flags); |
2084 | if (!IS_ERR(desc)) | |
2085 | active_low = flags & OF_GPIO_ACTIVE_LOW; | |
2086 | } else if (is_acpi_node(fwnode)) { | |
2087 | struct acpi_gpio_info info; | |
2088 | ||
c181fb3e | 2089 | desc = acpi_get_gpiod_by_index(to_acpi_node(fwnode), propname, 0, |
40b73183 MW |
2090 | &info); |
2091 | if (!IS_ERR(desc)) | |
2092 | active_low = info.active_low; | |
2093 | } | |
2094 | ||
2095 | if (IS_ERR(desc)) | |
2096 | return desc; | |
2097 | ||
2098 | ret = gpiod_request(desc, NULL); | |
2099 | if (ret) | |
2100 | return ERR_PTR(ret); | |
2101 | ||
2102 | /* Only value flag can be set from both DT and ACPI is active_low */ | |
2103 | if (active_low) | |
2104 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
2105 | ||
2106 | return desc; | |
2107 | } | |
2108 | EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod); | |
2109 | ||
29a1f233 TR |
2110 | /** |
2111 | * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO | |
2112 | * function | |
2113 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
2114 | * @con_id: function within the GPIO consumer | |
2115 | * @index: index of the GPIO to obtain in the consumer | |
39b2bbe3 | 2116 | * @flags: optional GPIO initialization flags |
29a1f233 TR |
2117 | * |
2118 | * This is equivalent to gpiod_get_index(), except that when no GPIO with the | |
2119 | * specified index was assigned to the requested function it will return NULL. | |
2120 | * This is convenient for drivers that need to handle optional GPIOs. | |
2121 | */ | |
b17d1bf1 | 2122 | struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev, |
29a1f233 | 2123 | const char *con_id, |
39b2bbe3 AC |
2124 | unsigned int index, |
2125 | enum gpiod_flags flags) | |
29a1f233 TR |
2126 | { |
2127 | struct gpio_desc *desc; | |
2128 | ||
39b2bbe3 | 2129 | desc = gpiod_get_index(dev, con_id, index, flags); |
29a1f233 TR |
2130 | if (IS_ERR(desc)) { |
2131 | if (PTR_ERR(desc) == -ENOENT) | |
2132 | return NULL; | |
2133 | } | |
2134 | ||
2135 | return desc; | |
2136 | } | |
b17d1bf1 | 2137 | EXPORT_SYMBOL_GPL(gpiod_get_index_optional); |
29a1f233 | 2138 | |
f625d460 BP |
2139 | /** |
2140 | * gpiod_hog - Hog the specified GPIO desc given the provided flags | |
2141 | * @desc: gpio whose value will be assigned | |
2142 | * @name: gpio line name | |
2143 | * @lflags: gpio_lookup_flags - returned from of_find_gpio() or | |
2144 | * of_get_gpio_hog() | |
2145 | * @dflags: gpiod_flags - optional GPIO initialization flags | |
2146 | */ | |
2147 | int gpiod_hog(struct gpio_desc *desc, const char *name, | |
2148 | unsigned long lflags, enum gpiod_flags dflags) | |
2149 | { | |
2150 | struct gpio_chip *chip; | |
2151 | struct gpio_desc *local_desc; | |
2152 | int hwnum; | |
2153 | int status; | |
2154 | ||
2155 | chip = gpiod_to_chip(desc); | |
2156 | hwnum = gpio_chip_hwgpio(desc); | |
2157 | ||
2158 | local_desc = gpiochip_request_own_desc(chip, hwnum, name); | |
2159 | if (IS_ERR(local_desc)) { | |
a713890d LW |
2160 | pr_err("requesting hog GPIO %s (chip %s, offset %d) failed\n", |
2161 | name, chip->label, hwnum); | |
f625d460 BP |
2162 | return PTR_ERR(local_desc); |
2163 | } | |
2164 | ||
2165 | status = gpiod_configure_flags(desc, name, lflags, dflags); | |
2166 | if (status < 0) { | |
a713890d LW |
2167 | pr_err("setup of hog GPIO %s (chip %s, offset %d) failed\n", |
2168 | name, chip->label, hwnum); | |
f625d460 BP |
2169 | gpiochip_free_own_desc(desc); |
2170 | return status; | |
2171 | } | |
2172 | ||
2173 | /* Mark GPIO as hogged so it can be identified and removed later */ | |
2174 | set_bit(FLAG_IS_HOGGED, &desc->flags); | |
2175 | ||
2176 | pr_info("GPIO line %d (%s) hogged as %s%s\n", | |
2177 | desc_to_gpio(desc), name, | |
2178 | (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input", | |
2179 | (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? | |
2180 | (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":""); | |
2181 | ||
2182 | return 0; | |
2183 | } | |
2184 | ||
2185 | /** | |
2186 | * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog | |
2187 | * @chip: gpio chip to act on | |
2188 | * | |
2189 | * This is only used by of_gpiochip_remove to free hogged gpios | |
2190 | */ | |
2191 | static void gpiochip_free_hogs(struct gpio_chip *chip) | |
2192 | { | |
2193 | int id; | |
2194 | ||
2195 | for (id = 0; id < chip->ngpio; id++) { | |
2196 | if (test_bit(FLAG_IS_HOGGED, &chip->desc[id].flags)) | |
2197 | gpiochip_free_own_desc(&chip->desc[id]); | |
2198 | } | |
2199 | } | |
2200 | ||
66858527 RI |
2201 | /** |
2202 | * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function | |
2203 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
2204 | * @con_id: function within the GPIO consumer | |
2205 | * @flags: optional GPIO initialization flags | |
2206 | * | |
2207 | * This function acquires all the GPIOs defined under a given function. | |
2208 | * | |
2209 | * Return a struct gpio_descs containing an array of descriptors, -ENOENT if | |
2210 | * no GPIO has been assigned to the requested function, or another IS_ERR() | |
2211 | * code if an error occurred while trying to acquire the GPIOs. | |
2212 | */ | |
2213 | struct gpio_descs *__must_check gpiod_get_array(struct device *dev, | |
2214 | const char *con_id, | |
2215 | enum gpiod_flags flags) | |
2216 | { | |
2217 | struct gpio_desc *desc; | |
2218 | struct gpio_descs *descs; | |
2219 | int count; | |
2220 | ||
2221 | count = gpiod_count(dev, con_id); | |
2222 | if (count < 0) | |
2223 | return ERR_PTR(count); | |
2224 | ||
2225 | descs = kzalloc(sizeof(*descs) + sizeof(descs->desc[0]) * count, | |
2226 | GFP_KERNEL); | |
2227 | if (!descs) | |
2228 | return ERR_PTR(-ENOMEM); | |
2229 | ||
2230 | for (descs->ndescs = 0; descs->ndescs < count; ) { | |
2231 | desc = gpiod_get_index(dev, con_id, descs->ndescs, flags); | |
2232 | if (IS_ERR(desc)) { | |
2233 | gpiod_put_array(descs); | |
2234 | return ERR_CAST(desc); | |
2235 | } | |
2236 | descs->desc[descs->ndescs] = desc; | |
2237 | descs->ndescs++; | |
2238 | } | |
2239 | return descs; | |
2240 | } | |
2241 | EXPORT_SYMBOL_GPL(gpiod_get_array); | |
2242 | ||
2243 | /** | |
2244 | * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO | |
2245 | * function | |
2246 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
2247 | * @con_id: function within the GPIO consumer | |
2248 | * @flags: optional GPIO initialization flags | |
2249 | * | |
2250 | * This is equivalent to gpiod_get_array(), except that when no GPIO was | |
2251 | * assigned to the requested function it will return NULL. | |
2252 | */ | |
2253 | struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev, | |
2254 | const char *con_id, | |
2255 | enum gpiod_flags flags) | |
2256 | { | |
2257 | struct gpio_descs *descs; | |
2258 | ||
2259 | descs = gpiod_get_array(dev, con_id, flags); | |
2260 | if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT)) | |
2261 | return NULL; | |
2262 | ||
2263 | return descs; | |
2264 | } | |
2265 | EXPORT_SYMBOL_GPL(gpiod_get_array_optional); | |
2266 | ||
bae48da2 AC |
2267 | /** |
2268 | * gpiod_put - dispose of a GPIO descriptor | |
2269 | * @desc: GPIO descriptor to dispose of | |
2270 | * | |
2271 | * No descriptor can be used after gpiod_put() has been called on it. | |
2272 | */ | |
2273 | void gpiod_put(struct gpio_desc *desc) | |
2274 | { | |
2275 | gpiod_free(desc); | |
372e722e | 2276 | } |
bae48da2 | 2277 | EXPORT_SYMBOL_GPL(gpiod_put); |
d2876d08 | 2278 | |
66858527 RI |
2279 | /** |
2280 | * gpiod_put_array - dispose of multiple GPIO descriptors | |
2281 | * @descs: struct gpio_descs containing an array of descriptors | |
2282 | */ | |
2283 | void gpiod_put_array(struct gpio_descs *descs) | |
2284 | { | |
2285 | unsigned int i; | |
2286 | ||
2287 | for (i = 0; i < descs->ndescs; i++) | |
2288 | gpiod_put(descs->desc[i]); | |
2289 | ||
2290 | kfree(descs); | |
2291 | } | |
2292 | EXPORT_SYMBOL_GPL(gpiod_put_array); | |
2293 | ||
d2876d08 DB |
2294 | #ifdef CONFIG_DEBUG_FS |
2295 | ||
d2876d08 DB |
2296 | static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip) |
2297 | { | |
2298 | unsigned i; | |
2299 | unsigned gpio = chip->base; | |
6c0b4e6c | 2300 | struct gpio_desc *gdesc = &chip->desc[0]; |
d2876d08 | 2301 | int is_out; |
d468bf9e | 2302 | int is_irq; |
d2876d08 DB |
2303 | |
2304 | for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) { | |
2305 | if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) | |
2306 | continue; | |
2307 | ||
372e722e | 2308 | gpiod_get_direction(gdesc); |
d2876d08 | 2309 | is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); |
d468bf9e LW |
2310 | is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); |
2311 | seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s", | |
d2876d08 DB |
2312 | gpio, gdesc->label, |
2313 | is_out ? "out" : "in ", | |
2314 | chip->get | |
2315 | ? (chip->get(chip, i) ? "hi" : "lo") | |
d468bf9e LW |
2316 | : "? ", |
2317 | is_irq ? "IRQ" : " "); | |
d2876d08 DB |
2318 | seq_printf(s, "\n"); |
2319 | } | |
2320 | } | |
2321 | ||
f9c4a31f | 2322 | static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) |
d2876d08 | 2323 | { |
362432ae | 2324 | unsigned long flags; |
f9c4a31f | 2325 | struct gpio_chip *chip = NULL; |
cb1650d4 | 2326 | loff_t index = *pos; |
d2876d08 | 2327 | |
f9c4a31f | 2328 | s->private = ""; |
d2876d08 | 2329 | |
362432ae | 2330 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 | 2331 | list_for_each_entry(chip, &gpio_chips, list) |
362432ae GL |
2332 | if (index-- == 0) { |
2333 | spin_unlock_irqrestore(&gpio_lock, flags); | |
cb1650d4 | 2334 | return chip; |
f9c4a31f | 2335 | } |
362432ae | 2336 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f | 2337 | |
cb1650d4 | 2338 | return NULL; |
f9c4a31f TR |
2339 | } |
2340 | ||
2341 | static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
2342 | { | |
362432ae | 2343 | unsigned long flags; |
f9c4a31f | 2344 | struct gpio_chip *chip = v; |
f9c4a31f TR |
2345 | void *ret = NULL; |
2346 | ||
362432ae | 2347 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 AC |
2348 | if (list_is_last(&chip->list, &gpio_chips)) |
2349 | ret = NULL; | |
2350 | else | |
2351 | ret = list_entry(chip->list.next, struct gpio_chip, list); | |
362432ae | 2352 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f TR |
2353 | |
2354 | s->private = "\n"; | |
2355 | ++*pos; | |
2356 | ||
2357 | return ret; | |
2358 | } | |
2359 | ||
2360 | static void gpiolib_seq_stop(struct seq_file *s, void *v) | |
2361 | { | |
2362 | } | |
2363 | ||
2364 | static int gpiolib_seq_show(struct seq_file *s, void *v) | |
2365 | { | |
2366 | struct gpio_chip *chip = v; | |
2367 | struct device *dev; | |
2368 | ||
2369 | seq_printf(s, "%sGPIOs %d-%d", (char *)s->private, | |
2370 | chip->base, chip->base + chip->ngpio - 1); | |
2371 | dev = chip->dev; | |
2372 | if (dev) | |
2373 | seq_printf(s, ", %s/%s", dev->bus ? dev->bus->name : "no-bus", | |
2374 | dev_name(dev)); | |
2375 | if (chip->label) | |
2376 | seq_printf(s, ", %s", chip->label); | |
2377 | if (chip->can_sleep) | |
2378 | seq_printf(s, ", can sleep"); | |
2379 | seq_printf(s, ":\n"); | |
2380 | ||
2381 | if (chip->dbg_show) | |
2382 | chip->dbg_show(s, chip); | |
2383 | else | |
2384 | gpiolib_dbg_show(s, chip); | |
2385 | ||
d2876d08 DB |
2386 | return 0; |
2387 | } | |
2388 | ||
f9c4a31f TR |
2389 | static const struct seq_operations gpiolib_seq_ops = { |
2390 | .start = gpiolib_seq_start, | |
2391 | .next = gpiolib_seq_next, | |
2392 | .stop = gpiolib_seq_stop, | |
2393 | .show = gpiolib_seq_show, | |
2394 | }; | |
2395 | ||
d2876d08 DB |
2396 | static int gpiolib_open(struct inode *inode, struct file *file) |
2397 | { | |
f9c4a31f | 2398 | return seq_open(file, &gpiolib_seq_ops); |
d2876d08 DB |
2399 | } |
2400 | ||
828c0950 | 2401 | static const struct file_operations gpiolib_operations = { |
f9c4a31f | 2402 | .owner = THIS_MODULE, |
d2876d08 DB |
2403 | .open = gpiolib_open, |
2404 | .read = seq_read, | |
2405 | .llseek = seq_lseek, | |
f9c4a31f | 2406 | .release = seq_release, |
d2876d08 DB |
2407 | }; |
2408 | ||
2409 | static int __init gpiolib_debugfs_init(void) | |
2410 | { | |
2411 | /* /sys/kernel/debug/gpio */ | |
2412 | (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO, | |
2413 | NULL, NULL, &gpiolib_operations); | |
2414 | return 0; | |
2415 | } | |
2416 | subsys_initcall(gpiolib_debugfs_init); | |
2417 | ||
2418 | #endif /* DEBUG_FS */ |