Commit | Line | Data |
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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 | |
d2876d08 DB |
50 | static struct gpio_desc gpio_desc[ARCH_NR_GPIOS]; |
51 | ||
6c0b4e6c AC |
52 | #define GPIO_OFFSET_VALID(chip, offset) (offset >= 0 && offset < chip->ngpio) |
53 | ||
bae48da2 AC |
54 | static DEFINE_MUTEX(gpio_lookup_lock); |
55 | static LIST_HEAD(gpio_lookup_list); | |
0eb4c6c2 | 56 | LIST_HEAD(gpio_chips); |
1a2a99c6 | 57 | |
d2876d08 DB |
58 | static inline void desc_set_label(struct gpio_desc *d, const char *label) |
59 | { | |
d2876d08 | 60 | d->label = label; |
d2876d08 DB |
61 | } |
62 | ||
372e722e AC |
63 | /** |
64 | * Convert a GPIO number to its descriptor | |
65 | */ | |
79a9becd | 66 | struct gpio_desc *gpio_to_desc(unsigned gpio) |
372e722e AC |
67 | { |
68 | if (WARN(!gpio_is_valid(gpio), "invalid GPIO %d\n", gpio)) | |
69 | return NULL; | |
70 | else | |
71 | return &gpio_desc[gpio]; | |
72 | } | |
79a9becd | 73 | EXPORT_SYMBOL_GPL(gpio_to_desc); |
372e722e | 74 | |
d468bf9e | 75 | /** |
bb1e88cc | 76 | * Get the GPIO descriptor corresponding to the given hw number for this chip. |
d468bf9e | 77 | */ |
bb1e88cc AC |
78 | struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, |
79 | u16 hwnum) | |
d468bf9e | 80 | { |
bb1e88cc | 81 | if (hwnum >= chip->ngpio) |
b7d0a28a | 82 | return ERR_PTR(-EINVAL); |
d468bf9e | 83 | |
bb1e88cc | 84 | return &chip->desc[hwnum]; |
d468bf9e | 85 | } |
372e722e AC |
86 | |
87 | /** | |
88 | * Convert a GPIO descriptor to the integer namespace. | |
89 | * This should disappear in the future but is needed since we still | |
90 | * use GPIO numbers for error messages and sysfs nodes | |
91 | */ | |
79a9becd | 92 | int desc_to_gpio(const struct gpio_desc *desc) |
372e722e | 93 | { |
8c0fca81 | 94 | return desc - &gpio_desc[0]; |
372e722e | 95 | } |
79a9becd | 96 | EXPORT_SYMBOL_GPL(desc_to_gpio); |
372e722e AC |
97 | |
98 | ||
79a9becd AC |
99 | /** |
100 | * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs | |
101 | * @desc: descriptor to return the chip of | |
102 | */ | |
103 | struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) | |
372e722e | 104 | { |
bcabdef1 | 105 | return desc ? desc->chip : NULL; |
372e722e | 106 | } |
79a9becd | 107 | EXPORT_SYMBOL_GPL(gpiod_to_chip); |
d2876d08 | 108 | |
8d0aab2f AV |
109 | /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ |
110 | static int gpiochip_find_base(int ngpio) | |
111 | { | |
83cabe33 AC |
112 | struct gpio_chip *chip; |
113 | int base = ARCH_NR_GPIOS - ngpio; | |
8d0aab2f | 114 | |
83cabe33 AC |
115 | list_for_each_entry_reverse(chip, &gpio_chips, list) { |
116 | /* found a free space? */ | |
117 | if (chip->base + chip->ngpio <= base) | |
118 | break; | |
119 | else | |
120 | /* nope, check the space right before the chip */ | |
121 | base = chip->base - ngpio; | |
8d0aab2f AV |
122 | } |
123 | ||
83cabe33 | 124 | if (gpio_is_valid(base)) { |
8d0aab2f | 125 | pr_debug("%s: found new base at %d\n", __func__, base); |
83cabe33 AC |
126 | return base; |
127 | } else { | |
128 | pr_err("%s: cannot find free range\n", __func__); | |
129 | return -ENOSPC; | |
169b6a7a | 130 | } |
169b6a7a AV |
131 | } |
132 | ||
79a9becd AC |
133 | /** |
134 | * gpiod_get_direction - return the current direction of a GPIO | |
135 | * @desc: GPIO to get the direction of | |
136 | * | |
137 | * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error. | |
138 | * | |
139 | * This function may sleep if gpiod_cansleep() is true. | |
140 | */ | |
141 | int gpiod_get_direction(const struct gpio_desc *desc) | |
80b0a602 MN |
142 | { |
143 | struct gpio_chip *chip; | |
372e722e | 144 | unsigned offset; |
80b0a602 MN |
145 | int status = -EINVAL; |
146 | ||
372e722e AC |
147 | chip = gpiod_to_chip(desc); |
148 | offset = gpio_chip_hwgpio(desc); | |
80b0a602 MN |
149 | |
150 | if (!chip->get_direction) | |
151 | return status; | |
152 | ||
372e722e | 153 | status = chip->get_direction(chip, offset); |
80b0a602 MN |
154 | if (status > 0) { |
155 | /* GPIOF_DIR_IN, or other positive */ | |
156 | status = 1; | |
def63433 AC |
157 | /* FLAG_IS_OUT is just a cache of the result of get_direction(), |
158 | * so it does not affect constness per se */ | |
159 | clear_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); | |
80b0a602 MN |
160 | } |
161 | if (status == 0) { | |
162 | /* GPIOF_DIR_OUT */ | |
def63433 | 163 | set_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); |
80b0a602 MN |
164 | } |
165 | return status; | |
166 | } | |
79a9becd | 167 | EXPORT_SYMBOL_GPL(gpiod_get_direction); |
80b0a602 | 168 | |
1a989d0f AC |
169 | /* |
170 | * Add a new chip to the global chips list, keeping the list of chips sorted | |
171 | * by base order. | |
172 | * | |
173 | * Return -EBUSY if the new chip overlaps with some other chip's integer | |
174 | * space. | |
175 | */ | |
176 | static int gpiochip_add_to_list(struct gpio_chip *chip) | |
177 | { | |
178 | struct list_head *pos = &gpio_chips; | |
179 | struct gpio_chip *_chip; | |
180 | int err = 0; | |
181 | ||
182 | /* find where to insert our chip */ | |
183 | list_for_each(pos, &gpio_chips) { | |
184 | _chip = list_entry(pos, struct gpio_chip, list); | |
185 | /* shall we insert before _chip? */ | |
186 | if (_chip->base >= chip->base + chip->ngpio) | |
187 | break; | |
188 | } | |
189 | ||
190 | /* are we stepping on the chip right before? */ | |
191 | if (pos != &gpio_chips && pos->prev != &gpio_chips) { | |
192 | _chip = list_entry(pos->prev, struct gpio_chip, list); | |
193 | if (_chip->base + _chip->ngpio > chip->base) { | |
194 | dev_err(chip->dev, | |
195 | "GPIO integer space overlap, cannot add chip\n"); | |
196 | err = -EBUSY; | |
197 | } | |
198 | } | |
199 | ||
200 | if (!err) | |
201 | list_add_tail(&chip->list, pos); | |
202 | ||
203 | return err; | |
204 | } | |
205 | ||
d2876d08 DB |
206 | /** |
207 | * gpiochip_add() - register a gpio_chip | |
208 | * @chip: the chip to register, with chip->base initialized | |
209 | * Context: potentially before irqs or kmalloc will work | |
210 | * | |
211 | * Returns a negative errno if the chip can't be registered, such as | |
212 | * because the chip->base is invalid or already associated with a | |
213 | * different chip. Otherwise it returns zero as a success code. | |
8d0aab2f | 214 | * |
d8f388d8 DB |
215 | * When gpiochip_add() is called very early during boot, so that GPIOs |
216 | * can be freely used, the chip->dev device must be registered before | |
217 | * the gpio framework's arch_initcall(). Otherwise sysfs initialization | |
218 | * for GPIOs will fail rudely. | |
219 | * | |
8d0aab2f AV |
220 | * If chip->base is negative, this requests dynamic assignment of |
221 | * a range of valid GPIOs. | |
d2876d08 DB |
222 | */ |
223 | int gpiochip_add(struct gpio_chip *chip) | |
224 | { | |
225 | unsigned long flags; | |
226 | int status = 0; | |
227 | unsigned id; | |
8d0aab2f | 228 | int base = chip->base; |
d2876d08 | 229 | |
bff5fda9 | 230 | if ((!gpio_is_valid(base) || !gpio_is_valid(base + chip->ngpio - 1)) |
8d0aab2f | 231 | && base >= 0) { |
d2876d08 DB |
232 | status = -EINVAL; |
233 | goto fail; | |
234 | } | |
235 | ||
236 | spin_lock_irqsave(&gpio_lock, flags); | |
237 | ||
8d0aab2f AV |
238 | if (base < 0) { |
239 | base = gpiochip_find_base(chip->ngpio); | |
240 | if (base < 0) { | |
241 | status = base; | |
d8f388d8 | 242 | goto unlock; |
8d0aab2f AV |
243 | } |
244 | chip->base = base; | |
245 | } | |
246 | ||
1a989d0f AC |
247 | status = gpiochip_add_to_list(chip); |
248 | ||
d2876d08 | 249 | if (status == 0) { |
6c0b4e6c AC |
250 | chip->desc = &gpio_desc[chip->base]; |
251 | ||
252 | for (id = 0; id < chip->ngpio; id++) { | |
253 | struct gpio_desc *desc = &chip->desc[id]; | |
254 | desc->chip = chip; | |
d8f388d8 DB |
255 | |
256 | /* REVISIT: most hardware initializes GPIOs as | |
257 | * inputs (often with pullups enabled) so power | |
258 | * usage is minimized. Linux code should set the | |
259 | * gpio direction first thing; but until it does, | |
80b0a602 | 260 | * and in case chip->get_direction is not set, |
d8f388d8 DB |
261 | * we may expose the wrong direction in sysfs. |
262 | */ | |
6c0b4e6c | 263 | desc->flags = !chip->direction_input |
d8f388d8 DB |
264 | ? (1 << FLAG_IS_OUT) |
265 | : 0; | |
d2876d08 DB |
266 | } |
267 | } | |
268 | ||
3bae4811 ZG |
269 | spin_unlock_irqrestore(&gpio_lock, flags); |
270 | ||
f23f1516 SH |
271 | #ifdef CONFIG_PINCTRL |
272 | INIT_LIST_HEAD(&chip->pin_ranges); | |
273 | #endif | |
274 | ||
391c970c | 275 | of_gpiochip_add(chip); |
664e3e5a | 276 | acpi_gpiochip_add(chip); |
391c970c | 277 | |
cedb1881 AV |
278 | if (status) |
279 | goto fail; | |
280 | ||
281 | status = gpiochip_export(chip); | |
282 | if (status) | |
283 | goto fail; | |
284 | ||
7589e59f | 285 | pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__, |
64842aad GL |
286 | chip->base, chip->base + chip->ngpio - 1, |
287 | chip->label ? : "generic"); | |
288 | ||
cedb1881 | 289 | return 0; |
3bae4811 ZG |
290 | |
291 | unlock: | |
292 | spin_unlock_irqrestore(&gpio_lock, flags); | |
d2876d08 DB |
293 | fail: |
294 | /* failures here can mean systems won't boot... */ | |
7589e59f | 295 | pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__, |
cedb1881 AV |
296 | chip->base, chip->base + chip->ngpio - 1, |
297 | chip->label ? : "generic"); | |
d2876d08 DB |
298 | return status; |
299 | } | |
300 | EXPORT_SYMBOL_GPL(gpiochip_add); | |
301 | ||
14250520 LW |
302 | /* Forward-declaration */ |
303 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); | |
304 | ||
d2876d08 DB |
305 | /** |
306 | * gpiochip_remove() - unregister a gpio_chip | |
307 | * @chip: the chip to unregister | |
308 | * | |
309 | * A gpio_chip with any GPIOs still requested may not be removed. | |
310 | */ | |
311 | int gpiochip_remove(struct gpio_chip *chip) | |
312 | { | |
313 | unsigned long flags; | |
314 | int status = 0; | |
315 | unsigned id; | |
316 | ||
6072b9dc MW |
317 | acpi_gpiochip_remove(chip); |
318 | ||
d2876d08 DB |
319 | spin_lock_irqsave(&gpio_lock, flags); |
320 | ||
14250520 | 321 | gpiochip_irqchip_remove(chip); |
9ef0d6f7 | 322 | gpiochip_remove_pin_ranges(chip); |
391c970c AV |
323 | of_gpiochip_remove(chip); |
324 | ||
6c0b4e6c AC |
325 | for (id = 0; id < chip->ngpio; id++) { |
326 | if (test_bit(FLAG_REQUESTED, &chip->desc[id].flags)) { | |
d2876d08 DB |
327 | status = -EBUSY; |
328 | break; | |
329 | } | |
330 | } | |
331 | if (status == 0) { | |
6c0b4e6c AC |
332 | for (id = 0; id < chip->ngpio; id++) |
333 | chip->desc[id].chip = NULL; | |
1a989d0f AC |
334 | |
335 | list_del(&chip->list); | |
d2876d08 DB |
336 | } |
337 | ||
338 | spin_unlock_irqrestore(&gpio_lock, flags); | |
d8f388d8 DB |
339 | |
340 | if (status == 0) | |
341 | gpiochip_unexport(chip); | |
342 | ||
d2876d08 DB |
343 | return status; |
344 | } | |
345 | EXPORT_SYMBOL_GPL(gpiochip_remove); | |
346 | ||
594fa265 GL |
347 | /** |
348 | * gpiochip_find() - iterator for locating a specific gpio_chip | |
349 | * @data: data to pass to match function | |
350 | * @callback: Callback function to check gpio_chip | |
351 | * | |
352 | * Similar to bus_find_device. It returns a reference to a gpio_chip as | |
353 | * determined by a user supplied @match callback. The callback should return | |
354 | * 0 if the device doesn't match and non-zero if it does. If the callback is | |
355 | * non-zero, this function will return to the caller and not iterate over any | |
356 | * more gpio_chips. | |
357 | */ | |
07ce8ec7 | 358 | struct gpio_chip *gpiochip_find(void *data, |
6e2cf651 | 359 | int (*match)(struct gpio_chip *chip, |
3d0f7cf0 | 360 | void *data)) |
594fa265 | 361 | { |
125eef96 | 362 | struct gpio_chip *chip; |
594fa265 | 363 | unsigned long flags; |
594fa265 GL |
364 | |
365 | spin_lock_irqsave(&gpio_lock, flags); | |
125eef96 AC |
366 | list_for_each_entry(chip, &gpio_chips, list) |
367 | if (match(chip, data)) | |
594fa265 | 368 | break; |
125eef96 AC |
369 | |
370 | /* No match? */ | |
371 | if (&chip->list == &gpio_chips) | |
372 | chip = NULL; | |
594fa265 GL |
373 | spin_unlock_irqrestore(&gpio_lock, flags); |
374 | ||
375 | return chip; | |
376 | } | |
8fa0c9bf | 377 | EXPORT_SYMBOL_GPL(gpiochip_find); |
d2876d08 | 378 | |
79697ef9 AC |
379 | static int gpiochip_match_name(struct gpio_chip *chip, void *data) |
380 | { | |
381 | const char *name = data; | |
382 | ||
383 | return !strcmp(chip->label, name); | |
384 | } | |
385 | ||
386 | static struct gpio_chip *find_chip_by_name(const char *name) | |
387 | { | |
388 | return gpiochip_find((void *)name, gpiochip_match_name); | |
389 | } | |
390 | ||
14250520 LW |
391 | #ifdef CONFIG_GPIOLIB_IRQCHIP |
392 | ||
393 | /* | |
394 | * The following is irqchip helper code for gpiochips. | |
395 | */ | |
396 | ||
397 | /** | |
398 | * gpiochip_add_chained_irqchip() - adds a chained irqchip to a gpiochip | |
399 | * @gpiochip: the gpiochip to add the irqchip to | |
400 | * @irqchip: the irqchip to add to the gpiochip | |
401 | * @parent_irq: the irq number corresponding to the parent IRQ for this | |
402 | * chained irqchip | |
403 | * @parent_handler: the parent interrupt handler for the accumulated IRQ | |
404 | * coming out of the gpiochip | |
405 | */ | |
406 | void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, | |
407 | struct irq_chip *irqchip, | |
408 | int parent_irq, | |
409 | irq_flow_handler_t parent_handler) | |
410 | { | |
1c8732bb LW |
411 | if (gpiochip->can_sleep) { |
412 | chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n"); | |
413 | return; | |
414 | } | |
415 | ||
14250520 LW |
416 | irq_set_chained_handler(parent_irq, parent_handler); |
417 | /* | |
418 | * The parent irqchip is already using the chip_data for this | |
419 | * irqchip, so our callbacks simply use the handler_data. | |
420 | */ | |
421 | irq_set_handler_data(parent_irq, gpiochip); | |
422 | } | |
423 | EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip); | |
424 | ||
e45d1c80 LW |
425 | /* |
426 | * This lock class tells lockdep that GPIO irqs are in a different | |
427 | * category than their parents, so it won't report false recursion. | |
428 | */ | |
429 | static struct lock_class_key gpiochip_irq_lock_class; | |
430 | ||
14250520 LW |
431 | /** |
432 | * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip | |
433 | * @d: the irqdomain used by this irqchip | |
434 | * @irq: the global irq number used by this GPIO irqchip irq | |
435 | * @hwirq: the local IRQ/GPIO line offset on this gpiochip | |
436 | * | |
437 | * This function will set up the mapping for a certain IRQ line on a | |
438 | * gpiochip by assigning the gpiochip as chip data, and using the irqchip | |
439 | * stored inside the gpiochip. | |
440 | */ | |
441 | static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, | |
442 | irq_hw_number_t hwirq) | |
443 | { | |
444 | struct gpio_chip *chip = d->host_data; | |
445 | ||
14250520 | 446 | irq_set_chip_data(irq, chip); |
e45d1c80 | 447 | irq_set_lockdep_class(irq, &gpiochip_irq_lock_class); |
7633fb95 | 448 | irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler); |
1c8732bb LW |
449 | /* Chips that can sleep need nested thread handlers */ |
450 | if (chip->can_sleep) | |
451 | irq_set_nested_thread(irq, 1); | |
14250520 LW |
452 | #ifdef CONFIG_ARM |
453 | set_irq_flags(irq, IRQF_VALID); | |
454 | #else | |
455 | irq_set_noprobe(irq); | |
456 | #endif | |
1333b90f LW |
457 | /* |
458 | * No set-up of the hardware will happen if IRQ_TYPE_NONE | |
459 | * is passed as default type. | |
460 | */ | |
461 | if (chip->irq_default_type != IRQ_TYPE_NONE) | |
462 | irq_set_irq_type(irq, chip->irq_default_type); | |
14250520 LW |
463 | |
464 | return 0; | |
465 | } | |
466 | ||
c3626fde LW |
467 | static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) |
468 | { | |
1c8732bb LW |
469 | struct gpio_chip *chip = d->host_data; |
470 | ||
c3626fde LW |
471 | #ifdef CONFIG_ARM |
472 | set_irq_flags(irq, 0); | |
473 | #endif | |
1c8732bb LW |
474 | if (chip->can_sleep) |
475 | irq_set_nested_thread(irq, 0); | |
c3626fde LW |
476 | irq_set_chip_and_handler(irq, NULL, NULL); |
477 | irq_set_chip_data(irq, NULL); | |
478 | } | |
479 | ||
14250520 LW |
480 | static const struct irq_domain_ops gpiochip_domain_ops = { |
481 | .map = gpiochip_irq_map, | |
c3626fde | 482 | .unmap = gpiochip_irq_unmap, |
14250520 LW |
483 | /* Virtually all GPIO irqchips are twocell:ed */ |
484 | .xlate = irq_domain_xlate_twocell, | |
485 | }; | |
486 | ||
487 | static int gpiochip_irq_reqres(struct irq_data *d) | |
488 | { | |
489 | struct gpio_chip *chip = irq_data_get_irq_chip_data(d); | |
490 | ||
491 | if (gpio_lock_as_irq(chip, d->hwirq)) { | |
492 | chip_err(chip, | |
493 | "unable to lock HW IRQ %lu for IRQ\n", | |
494 | d->hwirq); | |
495 | return -EINVAL; | |
496 | } | |
497 | return 0; | |
498 | } | |
499 | ||
500 | static void gpiochip_irq_relres(struct irq_data *d) | |
501 | { | |
502 | struct gpio_chip *chip = irq_data_get_irq_chip_data(d); | |
503 | ||
504 | gpio_unlock_as_irq(chip, d->hwirq); | |
505 | } | |
506 | ||
507 | static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) | |
508 | { | |
509 | return irq_find_mapping(chip->irqdomain, offset); | |
510 | } | |
511 | ||
512 | /** | |
513 | * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip | |
514 | * @gpiochip: the gpiochip to remove the irqchip from | |
515 | * | |
516 | * This is called only from gpiochip_remove() | |
517 | */ | |
518 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) | |
519 | { | |
c3626fde LW |
520 | unsigned int offset; |
521 | ||
afa82fab MW |
522 | acpi_gpiochip_free_interrupts(gpiochip); |
523 | ||
c3626fde LW |
524 | /* Remove all IRQ mappings and delete the domain */ |
525 | if (gpiochip->irqdomain) { | |
526 | for (offset = 0; offset < gpiochip->ngpio; offset++) | |
527 | irq_dispose_mapping(gpiochip->irq_base + offset); | |
14250520 | 528 | irq_domain_remove(gpiochip->irqdomain); |
c3626fde | 529 | } |
14250520 LW |
530 | |
531 | if (gpiochip->irqchip) { | |
532 | gpiochip->irqchip->irq_request_resources = NULL; | |
533 | gpiochip->irqchip->irq_release_resources = NULL; | |
534 | gpiochip->irqchip = NULL; | |
535 | } | |
536 | } | |
537 | ||
538 | /** | |
539 | * gpiochip_irqchip_add() - adds an irqchip to a gpiochip | |
540 | * @gpiochip: the gpiochip to add the irqchip to | |
541 | * @irqchip: the irqchip to add to the gpiochip | |
542 | * @first_irq: if not dynamically assigned, the base (first) IRQ to | |
543 | * allocate gpiochip irqs from | |
544 | * @handler: the irq handler to use (often a predefined irq core function) | |
1333b90f LW |
545 | * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE |
546 | * to have the core avoid setting up any default type in the hardware. | |
14250520 LW |
547 | * |
548 | * This function closely associates a certain irqchip with a certain | |
549 | * gpiochip, providing an irq domain to translate the local IRQs to | |
550 | * global irqs in the gpiolib core, and making sure that the gpiochip | |
551 | * is passed as chip data to all related functions. Driver callbacks | |
552 | * need to use container_of() to get their local state containers back | |
553 | * from the gpiochip passed as chip data. An irqdomain will be stored | |
554 | * in the gpiochip that shall be used by the driver to handle IRQ number | |
555 | * translation. The gpiochip will need to be initialized and registered | |
556 | * before calling this function. | |
557 | * | |
c3626fde LW |
558 | * This function will handle two cell:ed simple IRQs and assumes all |
559 | * the pins on the gpiochip can generate a unique IRQ. Everything else | |
14250520 LW |
560 | * need to be open coded. |
561 | */ | |
562 | int gpiochip_irqchip_add(struct gpio_chip *gpiochip, | |
563 | struct irq_chip *irqchip, | |
564 | unsigned int first_irq, | |
565 | irq_flow_handler_t handler, | |
566 | unsigned int type) | |
567 | { | |
568 | struct device_node *of_node; | |
569 | unsigned int offset; | |
c3626fde | 570 | unsigned irq_base = 0; |
14250520 LW |
571 | |
572 | if (!gpiochip || !irqchip) | |
573 | return -EINVAL; | |
574 | ||
575 | if (!gpiochip->dev) { | |
576 | pr_err("missing gpiochip .dev parent pointer\n"); | |
577 | return -EINVAL; | |
578 | } | |
579 | of_node = gpiochip->dev->of_node; | |
580 | #ifdef CONFIG_OF_GPIO | |
581 | /* | |
582 | * If the gpiochip has an assigned OF node this takes precendence | |
583 | * FIXME: get rid of this and use gpiochip->dev->of_node everywhere | |
584 | */ | |
585 | if (gpiochip->of_node) | |
586 | of_node = gpiochip->of_node; | |
587 | #endif | |
588 | gpiochip->irqchip = irqchip; | |
589 | gpiochip->irq_handler = handler; | |
590 | gpiochip->irq_default_type = type; | |
591 | gpiochip->to_irq = gpiochip_to_irq; | |
592 | gpiochip->irqdomain = irq_domain_add_simple(of_node, | |
593 | gpiochip->ngpio, first_irq, | |
594 | &gpiochip_domain_ops, gpiochip); | |
595 | if (!gpiochip->irqdomain) { | |
596 | gpiochip->irqchip = NULL; | |
597 | return -EINVAL; | |
598 | } | |
599 | irqchip->irq_request_resources = gpiochip_irq_reqres; | |
600 | irqchip->irq_release_resources = gpiochip_irq_relres; | |
601 | ||
602 | /* | |
603 | * Prepare the mapping since the irqchip shall be orthogonal to | |
604 | * any gpiochip calls. If the first_irq was zero, this is | |
605 | * necessary to allocate descriptors for all IRQs. | |
606 | */ | |
c3626fde LW |
607 | for (offset = 0; offset < gpiochip->ngpio; offset++) { |
608 | irq_base = irq_create_mapping(gpiochip->irqdomain, offset); | |
609 | if (offset == 0) | |
610 | /* | |
611 | * Store the base into the gpiochip to be used when | |
612 | * unmapping the irqs. | |
613 | */ | |
614 | gpiochip->irq_base = irq_base; | |
615 | } | |
14250520 | 616 | |
afa82fab MW |
617 | acpi_gpiochip_request_interrupts(gpiochip); |
618 | ||
14250520 LW |
619 | return 0; |
620 | } | |
621 | EXPORT_SYMBOL_GPL(gpiochip_irqchip_add); | |
622 | ||
623 | #else /* CONFIG_GPIOLIB_IRQCHIP */ | |
624 | ||
625 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {} | |
626 | ||
627 | #endif /* CONFIG_GPIOLIB_IRQCHIP */ | |
628 | ||
f23f1516 | 629 | #ifdef CONFIG_PINCTRL |
165adc9c | 630 | |
586a87e6 CR |
631 | /** |
632 | * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping | |
633 | * @chip: the gpiochip to add the range for | |
634 | * @pinctrl: the dev_name() of the pin controller to map to | |
635 | * @gpio_offset: the start offset in the current gpio_chip number space | |
636 | * @pin_group: name of the pin group inside the pin controller | |
637 | */ | |
638 | int gpiochip_add_pingroup_range(struct gpio_chip *chip, | |
639 | struct pinctrl_dev *pctldev, | |
640 | unsigned int gpio_offset, const char *pin_group) | |
641 | { | |
642 | struct gpio_pin_range *pin_range; | |
643 | int ret; | |
644 | ||
645 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); | |
646 | if (!pin_range) { | |
1a2a99c6 | 647 | chip_err(chip, "failed to allocate pin ranges\n"); |
586a87e6 CR |
648 | return -ENOMEM; |
649 | } | |
650 | ||
651 | /* Use local offset as range ID */ | |
652 | pin_range->range.id = gpio_offset; | |
653 | pin_range->range.gc = chip; | |
654 | pin_range->range.name = chip->label; | |
655 | pin_range->range.base = chip->base + gpio_offset; | |
656 | pin_range->pctldev = pctldev; | |
657 | ||
658 | ret = pinctrl_get_group_pins(pctldev, pin_group, | |
659 | &pin_range->range.pins, | |
660 | &pin_range->range.npins); | |
61c6375d MN |
661 | if (ret < 0) { |
662 | kfree(pin_range); | |
586a87e6 | 663 | return ret; |
61c6375d | 664 | } |
586a87e6 CR |
665 | |
666 | pinctrl_add_gpio_range(pctldev, &pin_range->range); | |
667 | ||
1a2a99c6 AS |
668 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n", |
669 | gpio_offset, gpio_offset + pin_range->range.npins - 1, | |
586a87e6 CR |
670 | pinctrl_dev_get_devname(pctldev), pin_group); |
671 | ||
672 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
673 | ||
674 | return 0; | |
675 | } | |
676 | EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); | |
677 | ||
3f0f8670 LW |
678 | /** |
679 | * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping | |
680 | * @chip: the gpiochip to add the range for | |
681 | * @pinctrl_name: the dev_name() of the pin controller to map to | |
316511c0 LW |
682 | * @gpio_offset: the start offset in the current gpio_chip number space |
683 | * @pin_offset: the start offset in the pin controller number space | |
3f0f8670 LW |
684 | * @npins: the number of pins from the offset of each pin space (GPIO and |
685 | * pin controller) to accumulate in this range | |
686 | */ | |
1e63d7b9 | 687 | int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, |
316511c0 | 688 | unsigned int gpio_offset, unsigned int pin_offset, |
3f0f8670 | 689 | unsigned int npins) |
f23f1516 SH |
690 | { |
691 | struct gpio_pin_range *pin_range; | |
b4d4b1f0 | 692 | int ret; |
f23f1516 | 693 | |
3f0f8670 | 694 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); |
f23f1516 | 695 | if (!pin_range) { |
1a2a99c6 | 696 | chip_err(chip, "failed to allocate pin ranges\n"); |
1e63d7b9 | 697 | return -ENOMEM; |
f23f1516 SH |
698 | } |
699 | ||
3f0f8670 | 700 | /* Use local offset as range ID */ |
316511c0 | 701 | pin_range->range.id = gpio_offset; |
3f0f8670 | 702 | pin_range->range.gc = chip; |
f23f1516 | 703 | pin_range->range.name = chip->label; |
316511c0 LW |
704 | pin_range->range.base = chip->base + gpio_offset; |
705 | pin_range->range.pin_base = pin_offset; | |
f23f1516 | 706 | pin_range->range.npins = npins; |
192c369c | 707 | pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, |
f23f1516 | 708 | &pin_range->range); |
8f23ca1a | 709 | if (IS_ERR(pin_range->pctldev)) { |
b4d4b1f0 | 710 | ret = PTR_ERR(pin_range->pctldev); |
1a2a99c6 | 711 | chip_err(chip, "could not create pin range\n"); |
3f0f8670 | 712 | kfree(pin_range); |
b4d4b1f0 | 713 | return ret; |
3f0f8670 | 714 | } |
1a2a99c6 AS |
715 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n", |
716 | gpio_offset, gpio_offset + npins - 1, | |
316511c0 LW |
717 | pinctl_name, |
718 | pin_offset, pin_offset + npins - 1); | |
f23f1516 SH |
719 | |
720 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
1e63d7b9 LW |
721 | |
722 | return 0; | |
f23f1516 | 723 | } |
165adc9c | 724 | EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); |
f23f1516 | 725 | |
3f0f8670 LW |
726 | /** |
727 | * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings | |
728 | * @chip: the chip to remove all the mappings for | |
729 | */ | |
f23f1516 SH |
730 | void gpiochip_remove_pin_ranges(struct gpio_chip *chip) |
731 | { | |
732 | struct gpio_pin_range *pin_range, *tmp; | |
733 | ||
734 | list_for_each_entry_safe(pin_range, tmp, &chip->pin_ranges, node) { | |
735 | list_del(&pin_range->node); | |
736 | pinctrl_remove_gpio_range(pin_range->pctldev, | |
737 | &pin_range->range); | |
3f0f8670 | 738 | kfree(pin_range); |
f23f1516 SH |
739 | } |
740 | } | |
165adc9c LW |
741 | EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); |
742 | ||
743 | #endif /* CONFIG_PINCTRL */ | |
f23f1516 | 744 | |
d2876d08 DB |
745 | /* These "optional" allocation calls help prevent drivers from stomping |
746 | * on each other, and help provide better diagnostics in debugfs. | |
747 | * They're called even less than the "set direction" calls. | |
748 | */ | |
77c2d792 | 749 | static int __gpiod_request(struct gpio_desc *desc, const char *label) |
d2876d08 | 750 | { |
77c2d792 MW |
751 | struct gpio_chip *chip = desc->chip; |
752 | int status; | |
d2876d08 DB |
753 | unsigned long flags; |
754 | ||
bcabdef1 AC |
755 | spin_lock_irqsave(&gpio_lock, flags); |
756 | ||
d2876d08 | 757 | /* NOTE: gpio_request() can be called in early boot, |
35e8bb51 | 758 | * before IRQs are enabled, for non-sleeping (SOC) GPIOs. |
d2876d08 DB |
759 | */ |
760 | ||
761 | if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { | |
762 | desc_set_label(desc, label ? : "?"); | |
763 | status = 0; | |
438d8908 | 764 | } else { |
d2876d08 | 765 | status = -EBUSY; |
7460db56 | 766 | goto done; |
35e8bb51 DB |
767 | } |
768 | ||
769 | if (chip->request) { | |
770 | /* chip->request may sleep */ | |
771 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 772 | status = chip->request(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
773 | spin_lock_irqsave(&gpio_lock, flags); |
774 | ||
775 | if (status < 0) { | |
776 | desc_set_label(desc, NULL); | |
35e8bb51 | 777 | clear_bit(FLAG_REQUESTED, &desc->flags); |
80b0a602 | 778 | goto done; |
35e8bb51 | 779 | } |
438d8908 | 780 | } |
80b0a602 MN |
781 | if (chip->get_direction) { |
782 | /* chip->get_direction may sleep */ | |
783 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 784 | gpiod_get_direction(desc); |
80b0a602 MN |
785 | spin_lock_irqsave(&gpio_lock, flags); |
786 | } | |
77c2d792 MW |
787 | done: |
788 | spin_unlock_irqrestore(&gpio_lock, flags); | |
789 | return status; | |
790 | } | |
791 | ||
0eb4c6c2 | 792 | int gpiod_request(struct gpio_desc *desc, const char *label) |
77c2d792 MW |
793 | { |
794 | int status = -EPROBE_DEFER; | |
795 | struct gpio_chip *chip; | |
796 | ||
797 | if (!desc) { | |
798 | pr_warn("%s: invalid GPIO\n", __func__); | |
799 | return -EINVAL; | |
800 | } | |
801 | ||
802 | chip = desc->chip; | |
803 | if (!chip) | |
804 | goto done; | |
805 | ||
806 | if (try_module_get(chip->owner)) { | |
807 | status = __gpiod_request(desc, label); | |
808 | if (status < 0) | |
809 | module_put(chip->owner); | |
810 | } | |
811 | ||
d2876d08 DB |
812 | done: |
813 | if (status) | |
7589e59f | 814 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
77c2d792 | 815 | |
d2876d08 DB |
816 | return status; |
817 | } | |
372e722e | 818 | |
77c2d792 | 819 | static bool __gpiod_free(struct gpio_desc *desc) |
d2876d08 | 820 | { |
77c2d792 | 821 | bool ret = false; |
d2876d08 | 822 | unsigned long flags; |
35e8bb51 | 823 | struct gpio_chip *chip; |
d2876d08 | 824 | |
3d599d1c UKK |
825 | might_sleep(); |
826 | ||
372e722e | 827 | gpiod_unexport(desc); |
d8f388d8 | 828 | |
d2876d08 DB |
829 | spin_lock_irqsave(&gpio_lock, flags); |
830 | ||
35e8bb51 DB |
831 | chip = desc->chip; |
832 | if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { | |
833 | if (chip->free) { | |
834 | spin_unlock_irqrestore(&gpio_lock, flags); | |
9c4ba946 | 835 | might_sleep_if(chip->can_sleep); |
372e722e | 836 | chip->free(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
837 | spin_lock_irqsave(&gpio_lock, flags); |
838 | } | |
d2876d08 | 839 | desc_set_label(desc, NULL); |
07697461 | 840 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); |
35e8bb51 | 841 | clear_bit(FLAG_REQUESTED, &desc->flags); |
aca5ce14 | 842 | clear_bit(FLAG_OPEN_DRAIN, &desc->flags); |
25553ff0 | 843 | clear_bit(FLAG_OPEN_SOURCE, &desc->flags); |
77c2d792 MW |
844 | ret = true; |
845 | } | |
d2876d08 DB |
846 | |
847 | spin_unlock_irqrestore(&gpio_lock, flags); | |
77c2d792 MW |
848 | return ret; |
849 | } | |
850 | ||
0eb4c6c2 | 851 | void gpiod_free(struct gpio_desc *desc) |
77c2d792 MW |
852 | { |
853 | if (desc && __gpiod_free(desc)) | |
854 | module_put(desc->chip->owner); | |
855 | else | |
856 | WARN_ON(extra_checks); | |
d2876d08 | 857 | } |
372e722e | 858 | |
d2876d08 DB |
859 | /** |
860 | * gpiochip_is_requested - return string iff signal was requested | |
861 | * @chip: controller managing the signal | |
862 | * @offset: of signal within controller's 0..(ngpio - 1) range | |
863 | * | |
864 | * Returns NULL if the GPIO is not currently requested, else a string. | |
9c8318ff AC |
865 | * The string returned is the label passed to gpio_request(); if none has been |
866 | * passed it is a meaningless, non-NULL constant. | |
d2876d08 DB |
867 | * |
868 | * This function is for use by GPIO controller drivers. The label can | |
869 | * help with diagnostics, and knowing that the signal is used as a GPIO | |
870 | * can help avoid accidentally multiplexing it to another controller. | |
871 | */ | |
872 | const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) | |
873 | { | |
6c0b4e6c | 874 | struct gpio_desc *desc; |
d2876d08 | 875 | |
6c0b4e6c | 876 | if (!GPIO_OFFSET_VALID(chip, offset)) |
d2876d08 | 877 | return NULL; |
6c0b4e6c AC |
878 | |
879 | desc = &chip->desc[offset]; | |
880 | ||
372e722e | 881 | if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) |
d2876d08 | 882 | return NULL; |
372e722e | 883 | return desc->label; |
d2876d08 DB |
884 | } |
885 | EXPORT_SYMBOL_GPL(gpiochip_is_requested); | |
886 | ||
77c2d792 MW |
887 | /** |
888 | * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor | |
889 | * @desc: GPIO descriptor to request | |
890 | * @label: label for the GPIO | |
891 | * | |
892 | * Function allows GPIO chip drivers to request and use their own GPIO | |
893 | * descriptors via gpiolib API. Difference to gpiod_request() is that this | |
894 | * function will not increase reference count of the GPIO chip module. This | |
895 | * allows the GPIO chip module to be unloaded as needed (we assume that the | |
896 | * GPIO chip driver handles freeing the GPIOs it has requested). | |
897 | */ | |
898 | int gpiochip_request_own_desc(struct gpio_desc *desc, const char *label) | |
899 | { | |
900 | if (!desc || !desc->chip) | |
901 | return -EINVAL; | |
902 | ||
903 | return __gpiod_request(desc, label); | |
904 | } | |
f7d4ad98 | 905 | EXPORT_SYMBOL_GPL(gpiochip_request_own_desc); |
77c2d792 MW |
906 | |
907 | /** | |
908 | * gpiochip_free_own_desc - Free GPIO requested by the chip driver | |
909 | * @desc: GPIO descriptor to free | |
910 | * | |
911 | * Function frees the given GPIO requested previously with | |
912 | * gpiochip_request_own_desc(). | |
913 | */ | |
914 | void gpiochip_free_own_desc(struct gpio_desc *desc) | |
915 | { | |
916 | if (desc) | |
917 | __gpiod_free(desc); | |
918 | } | |
f7d4ad98 | 919 | EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); |
d2876d08 DB |
920 | |
921 | /* Drivers MUST set GPIO direction before making get/set calls. In | |
922 | * some cases this is done in early boot, before IRQs are enabled. | |
923 | * | |
924 | * As a rule these aren't called more than once (except for drivers | |
925 | * using the open-drain emulation idiom) so these are natural places | |
926 | * to accumulate extra debugging checks. Note that we can't (yet) | |
927 | * rely on gpio_request() having been called beforehand. | |
928 | */ | |
929 | ||
79a9becd AC |
930 | /** |
931 | * gpiod_direction_input - set the GPIO direction to input | |
932 | * @desc: GPIO to set to input | |
933 | * | |
934 | * Set the direction of the passed GPIO to input, such as gpiod_get_value() can | |
935 | * be called safely on it. | |
936 | * | |
937 | * Return 0 in case of success, else an error code. | |
938 | */ | |
939 | int gpiod_direction_input(struct gpio_desc *desc) | |
d2876d08 | 940 | { |
d2876d08 | 941 | struct gpio_chip *chip; |
d2876d08 DB |
942 | int status = -EINVAL; |
943 | ||
be1a4b13 | 944 | if (!desc || !desc->chip) { |
bcabdef1 AC |
945 | pr_warn("%s: invalid GPIO\n", __func__); |
946 | return -EINVAL; | |
947 | } | |
948 | ||
be1a4b13 LW |
949 | chip = desc->chip; |
950 | if (!chip->get || !chip->direction_input) { | |
6424de5a MB |
951 | gpiod_warn(desc, |
952 | "%s: missing get() or direction_input() operations\n", | |
7589e59f | 953 | __func__); |
be1a4b13 LW |
954 | return -EIO; |
955 | } | |
956 | ||
d82da797 | 957 | status = chip->direction_input(chip, gpio_chip_hwgpio(desc)); |
d2876d08 DB |
958 | if (status == 0) |
959 | clear_bit(FLAG_IS_OUT, &desc->flags); | |
3f397c21 | 960 | |
372e722e | 961 | trace_gpio_direction(desc_to_gpio(desc), 1, status); |
d82da797 | 962 | |
d2876d08 DB |
963 | return status; |
964 | } | |
79a9becd | 965 | EXPORT_SYMBOL_GPL(gpiod_direction_input); |
372e722e | 966 | |
ef70bbe1 | 967 | static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) |
d2876d08 | 968 | { |
d2876d08 | 969 | struct gpio_chip *chip; |
d2876d08 DB |
970 | int status = -EINVAL; |
971 | ||
d468bf9e LW |
972 | /* GPIOs used for IRQs shall not be set as output */ |
973 | if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) { | |
974 | gpiod_err(desc, | |
975 | "%s: tried to set a GPIO tied to an IRQ as output\n", | |
976 | __func__); | |
977 | return -EIO; | |
978 | } | |
979 | ||
aca5ce14 LD |
980 | /* Open drain pin should not be driven to 1 */ |
981 | if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
372e722e | 982 | return gpiod_direction_input(desc); |
aca5ce14 | 983 | |
25553ff0 LD |
984 | /* Open source pin should not be driven to 0 */ |
985 | if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
372e722e | 986 | return gpiod_direction_input(desc); |
25553ff0 | 987 | |
be1a4b13 LW |
988 | chip = desc->chip; |
989 | if (!chip->set || !chip->direction_output) { | |
6424de5a MB |
990 | gpiod_warn(desc, |
991 | "%s: missing set() or direction_output() operations\n", | |
992 | __func__); | |
be1a4b13 LW |
993 | return -EIO; |
994 | } | |
995 | ||
d82da797 | 996 | status = chip->direction_output(chip, gpio_chip_hwgpio(desc), value); |
d2876d08 DB |
997 | if (status == 0) |
998 | set_bit(FLAG_IS_OUT, &desc->flags); | |
372e722e AC |
999 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
1000 | trace_gpio_direction(desc_to_gpio(desc), 0, status); | |
d2876d08 DB |
1001 | return status; |
1002 | } | |
ef70bbe1 PZ |
1003 | |
1004 | /** | |
1005 | * gpiod_direction_output_raw - set the GPIO direction to output | |
1006 | * @desc: GPIO to set to output | |
1007 | * @value: initial output value of the GPIO | |
1008 | * | |
1009 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
1010 | * be called safely on it. The initial value of the output must be specified | |
1011 | * as raw value on the physical line without regard for the ACTIVE_LOW status. | |
1012 | * | |
1013 | * Return 0 in case of success, else an error code. | |
1014 | */ | |
1015 | int gpiod_direction_output_raw(struct gpio_desc *desc, int value) | |
1016 | { | |
1017 | if (!desc || !desc->chip) { | |
1018 | pr_warn("%s: invalid GPIO\n", __func__); | |
1019 | return -EINVAL; | |
1020 | } | |
1021 | return _gpiod_direction_output_raw(desc, value); | |
1022 | } | |
1023 | EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); | |
1024 | ||
1025 | /** | |
90df4fe0 | 1026 | * gpiod_direction_output - set the GPIO direction to output |
ef70bbe1 PZ |
1027 | * @desc: GPIO to set to output |
1028 | * @value: initial output value of the GPIO | |
1029 | * | |
1030 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
1031 | * be called safely on it. The initial value of the output must be specified | |
1032 | * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1033 | * account. | |
1034 | * | |
1035 | * Return 0 in case of success, else an error code. | |
1036 | */ | |
1037 | int gpiod_direction_output(struct gpio_desc *desc, int value) | |
1038 | { | |
1039 | if (!desc || !desc->chip) { | |
1040 | pr_warn("%s: invalid GPIO\n", __func__); | |
1041 | return -EINVAL; | |
1042 | } | |
1043 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1044 | value = !value; | |
1045 | return _gpiod_direction_output_raw(desc, value); | |
1046 | } | |
79a9becd | 1047 | EXPORT_SYMBOL_GPL(gpiod_direction_output); |
d2876d08 | 1048 | |
c4b5be98 | 1049 | /** |
79a9becd | 1050 | * gpiod_set_debounce - sets @debounce time for a @gpio |
c4b5be98 FB |
1051 | * @gpio: the gpio to set debounce time |
1052 | * @debounce: debounce time is microseconds | |
65d87656 LW |
1053 | * |
1054 | * returns -ENOTSUPP if the controller does not support setting | |
1055 | * debounce. | |
c4b5be98 | 1056 | */ |
79a9becd | 1057 | int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) |
c4b5be98 | 1058 | { |
c4b5be98 | 1059 | struct gpio_chip *chip; |
c4b5be98 | 1060 | |
be1a4b13 | 1061 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1062 | pr_warn("%s: invalid GPIO\n", __func__); |
1063 | return -EINVAL; | |
1064 | } | |
1065 | ||
c4b5be98 | 1066 | chip = desc->chip; |
be1a4b13 | 1067 | if (!chip->set || !chip->set_debounce) { |
6424de5a MB |
1068 | gpiod_dbg(desc, |
1069 | "%s: missing set() or set_debounce() operations\n", | |
1070 | __func__); | |
65d87656 | 1071 | return -ENOTSUPP; |
be1a4b13 LW |
1072 | } |
1073 | ||
d82da797 | 1074 | return chip->set_debounce(chip, gpio_chip_hwgpio(desc), debounce); |
c4b5be98 | 1075 | } |
79a9becd | 1076 | EXPORT_SYMBOL_GPL(gpiod_set_debounce); |
372e722e | 1077 | |
79a9becd AC |
1078 | /** |
1079 | * gpiod_is_active_low - test whether a GPIO is active-low or not | |
1080 | * @desc: the gpio descriptor to test | |
1081 | * | |
1082 | * Returns 1 if the GPIO is active-low, 0 otherwise. | |
1083 | */ | |
1084 | int gpiod_is_active_low(const struct gpio_desc *desc) | |
372e722e | 1085 | { |
79a9becd | 1086 | return test_bit(FLAG_ACTIVE_LOW, &desc->flags); |
372e722e | 1087 | } |
79a9becd | 1088 | EXPORT_SYMBOL_GPL(gpiod_is_active_low); |
d2876d08 DB |
1089 | |
1090 | /* I/O calls are only valid after configuration completed; the relevant | |
1091 | * "is this a valid GPIO" error checks should already have been done. | |
1092 | * | |
1093 | * "Get" operations are often inlinable as reading a pin value register, | |
1094 | * and masking the relevant bit in that register. | |
1095 | * | |
1096 | * When "set" operations are inlinable, they involve writing that mask to | |
1097 | * one register to set a low value, or a different register to set it high. | |
1098 | * Otherwise locking is needed, so there may be little value to inlining. | |
1099 | * | |
1100 | *------------------------------------------------------------------------ | |
1101 | * | |
1102 | * IMPORTANT!!! The hot paths -- get/set value -- assume that callers | |
1103 | * have requested the GPIO. That can include implicit requesting by | |
1104 | * a direction setting call. Marking a gpio as requested locks its chip | |
1105 | * in memory, guaranteeing that these table lookups need no more locking | |
1106 | * and that gpiochip_remove() will fail. | |
1107 | * | |
1108 | * REVISIT when debugging, consider adding some instrumentation to ensure | |
1109 | * that the GPIO was actually requested. | |
1110 | */ | |
1111 | ||
23600969 | 1112 | static bool _gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 DB |
1113 | { |
1114 | struct gpio_chip *chip; | |
23600969 | 1115 | bool value; |
372e722e | 1116 | int offset; |
d2876d08 | 1117 | |
372e722e AC |
1118 | chip = desc->chip; |
1119 | offset = gpio_chip_hwgpio(desc); | |
23600969 | 1120 | value = chip->get ? chip->get(chip, offset) : false; |
372e722e | 1121 | trace_gpio_value(desc_to_gpio(desc), 1, value); |
3f397c21 | 1122 | return value; |
d2876d08 | 1123 | } |
372e722e | 1124 | |
d2876d08 | 1125 | /** |
79a9becd AC |
1126 | * gpiod_get_raw_value() - return a gpio's raw value |
1127 | * @desc: gpio whose value will be returned | |
d2876d08 | 1128 | * |
79a9becd AC |
1129 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding |
1130 | * its ACTIVE_LOW status. | |
1131 | * | |
1132 | * This function should be called from contexts where we cannot sleep, and will | |
1133 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1134 | */ |
79a9becd | 1135 | int gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 | 1136 | { |
bcabdef1 AC |
1137 | if (!desc) |
1138 | return 0; | |
e4e449e8 | 1139 | /* Should be using gpio_get_value_cansleep() */ |
d8e0ac08 | 1140 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 1141 | return _gpiod_get_raw_value(desc); |
d2876d08 | 1142 | } |
79a9becd | 1143 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value); |
372e722e | 1144 | |
79a9becd AC |
1145 | /** |
1146 | * gpiod_get_value() - return a gpio's value | |
1147 | * @desc: gpio whose value will be returned | |
1148 | * | |
1149 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
1150 | * account. | |
1151 | * | |
1152 | * This function should be called from contexts where we cannot sleep, and will | |
1153 | * complain if the GPIO chip functions potentially sleep. | |
1154 | */ | |
1155 | int gpiod_get_value(const struct gpio_desc *desc) | |
372e722e | 1156 | { |
79a9becd AC |
1157 | int value; |
1158 | if (!desc) | |
1159 | return 0; | |
1160 | /* Should be using gpio_get_value_cansleep() */ | |
1161 | WARN_ON(desc->chip->can_sleep); | |
1162 | ||
1163 | value = _gpiod_get_raw_value(desc); | |
1164 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1165 | value = !value; | |
1166 | ||
1167 | return value; | |
372e722e | 1168 | } |
79a9becd | 1169 | EXPORT_SYMBOL_GPL(gpiod_get_value); |
d2876d08 | 1170 | |
aca5ce14 LD |
1171 | /* |
1172 | * _gpio_set_open_drain_value() - Set the open drain gpio's value. | |
79a9becd | 1173 | * @desc: gpio descriptor whose state need to be set. |
aca5ce14 LD |
1174 | * @value: Non-zero for setting it HIGH otherise it will set to LOW. |
1175 | */ | |
23600969 | 1176 | static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value) |
aca5ce14 LD |
1177 | { |
1178 | int err = 0; | |
372e722e AC |
1179 | struct gpio_chip *chip = desc->chip; |
1180 | int offset = gpio_chip_hwgpio(desc); | |
1181 | ||
aca5ce14 | 1182 | if (value) { |
372e722e | 1183 | err = chip->direction_input(chip, offset); |
aca5ce14 | 1184 | if (!err) |
372e722e | 1185 | clear_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 1186 | } else { |
372e722e | 1187 | err = chip->direction_output(chip, offset, 0); |
aca5ce14 | 1188 | if (!err) |
372e722e | 1189 | set_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 1190 | } |
372e722e | 1191 | trace_gpio_direction(desc_to_gpio(desc), value, err); |
aca5ce14 | 1192 | if (err < 0) |
6424de5a MB |
1193 | gpiod_err(desc, |
1194 | "%s: Error in set_value for open drain err %d\n", | |
1195 | __func__, err); | |
aca5ce14 LD |
1196 | } |
1197 | ||
25553ff0 | 1198 | /* |
79a9becd AC |
1199 | * _gpio_set_open_source_value() - Set the open source gpio's value. |
1200 | * @desc: gpio descriptor whose state need to be set. | |
25553ff0 LD |
1201 | * @value: Non-zero for setting it HIGH otherise it will set to LOW. |
1202 | */ | |
23600969 | 1203 | static void _gpio_set_open_source_value(struct gpio_desc *desc, bool value) |
25553ff0 LD |
1204 | { |
1205 | int err = 0; | |
372e722e AC |
1206 | struct gpio_chip *chip = desc->chip; |
1207 | int offset = gpio_chip_hwgpio(desc); | |
1208 | ||
25553ff0 | 1209 | if (value) { |
372e722e | 1210 | err = chip->direction_output(chip, offset, 1); |
25553ff0 | 1211 | if (!err) |
372e722e | 1212 | set_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 1213 | } else { |
372e722e | 1214 | err = chip->direction_input(chip, offset); |
25553ff0 | 1215 | if (!err) |
372e722e | 1216 | clear_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 1217 | } |
372e722e | 1218 | trace_gpio_direction(desc_to_gpio(desc), !value, err); |
25553ff0 | 1219 | if (err < 0) |
6424de5a MB |
1220 | gpiod_err(desc, |
1221 | "%s: Error in set_value for open source err %d\n", | |
1222 | __func__, err); | |
25553ff0 LD |
1223 | } |
1224 | ||
23600969 | 1225 | static void _gpiod_set_raw_value(struct gpio_desc *desc, bool value) |
d2876d08 DB |
1226 | { |
1227 | struct gpio_chip *chip; | |
1228 | ||
372e722e | 1229 | chip = desc->chip; |
372e722e AC |
1230 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
1231 | if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
1232 | _gpio_set_open_drain_value(desc, value); | |
1233 | else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
1234 | _gpio_set_open_source_value(desc, value); | |
aca5ce14 | 1235 | else |
372e722e AC |
1236 | chip->set(chip, gpio_chip_hwgpio(desc), value); |
1237 | } | |
1238 | ||
d2876d08 | 1239 | /** |
79a9becd AC |
1240 | * gpiod_set_raw_value() - assign a gpio's raw value |
1241 | * @desc: gpio whose value will be assigned | |
d2876d08 | 1242 | * @value: value to assign |
d2876d08 | 1243 | * |
79a9becd AC |
1244 | * Set the raw value of the GPIO, i.e. the value of its physical line without |
1245 | * regard for its ACTIVE_LOW status. | |
1246 | * | |
1247 | * This function should be called from contexts where we cannot sleep, and will | |
1248 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1249 | */ |
79a9becd | 1250 | void gpiod_set_raw_value(struct gpio_desc *desc, int value) |
372e722e | 1251 | { |
bcabdef1 AC |
1252 | if (!desc) |
1253 | return; | |
e4e449e8 | 1254 | /* Should be using gpio_set_value_cansleep() */ |
d8e0ac08 | 1255 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 1256 | _gpiod_set_raw_value(desc, value); |
d2876d08 | 1257 | } |
79a9becd | 1258 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value); |
d2876d08 DB |
1259 | |
1260 | /** | |
79a9becd AC |
1261 | * gpiod_set_value() - assign a gpio's value |
1262 | * @desc: gpio whose value will be assigned | |
1263 | * @value: value to assign | |
1264 | * | |
1265 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1266 | * account | |
d2876d08 | 1267 | * |
79a9becd AC |
1268 | * This function should be called from contexts where we cannot sleep, and will |
1269 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1270 | */ |
79a9becd | 1271 | void gpiod_set_value(struct gpio_desc *desc, int value) |
d2876d08 | 1272 | { |
bcabdef1 | 1273 | if (!desc) |
79a9becd AC |
1274 | return; |
1275 | /* Should be using gpio_set_value_cansleep() */ | |
1276 | WARN_ON(desc->chip->can_sleep); | |
1277 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1278 | value = !value; | |
1279 | _gpiod_set_raw_value(desc, value); | |
372e722e | 1280 | } |
79a9becd | 1281 | EXPORT_SYMBOL_GPL(gpiod_set_value); |
d2876d08 | 1282 | |
d2876d08 | 1283 | /** |
79a9becd AC |
1284 | * gpiod_cansleep() - report whether gpio value access may sleep |
1285 | * @desc: gpio to check | |
d2876d08 | 1286 | * |
d2876d08 | 1287 | */ |
79a9becd | 1288 | int gpiod_cansleep(const struct gpio_desc *desc) |
372e722e | 1289 | { |
bcabdef1 AC |
1290 | if (!desc) |
1291 | return 0; | |
372e722e | 1292 | return desc->chip->can_sleep; |
d2876d08 | 1293 | } |
79a9becd | 1294 | EXPORT_SYMBOL_GPL(gpiod_cansleep); |
d2876d08 | 1295 | |
0f6d504e | 1296 | /** |
79a9becd AC |
1297 | * gpiod_to_irq() - return the IRQ corresponding to a GPIO |
1298 | * @desc: gpio whose IRQ will be returned (already requested) | |
0f6d504e | 1299 | * |
79a9becd AC |
1300 | * Return the IRQ corresponding to the passed GPIO, or an error code in case of |
1301 | * error. | |
0f6d504e | 1302 | */ |
79a9becd | 1303 | int gpiod_to_irq(const struct gpio_desc *desc) |
0f6d504e DB |
1304 | { |
1305 | struct gpio_chip *chip; | |
372e722e | 1306 | int offset; |
0f6d504e | 1307 | |
bcabdef1 AC |
1308 | if (!desc) |
1309 | return -EINVAL; | |
372e722e AC |
1310 | chip = desc->chip; |
1311 | offset = gpio_chip_hwgpio(desc); | |
1312 | return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO; | |
0f6d504e | 1313 | } |
79a9becd | 1314 | EXPORT_SYMBOL_GPL(gpiod_to_irq); |
0f6d504e | 1315 | |
d468bf9e | 1316 | /** |
d74be6df AC |
1317 | * gpio_lock_as_irq() - lock a GPIO to be used as IRQ |
1318 | * @chip: the chip the GPIO to lock belongs to | |
1319 | * @offset: the offset of the GPIO to lock as IRQ | |
d468bf9e LW |
1320 | * |
1321 | * This is used directly by GPIO drivers that want to lock down | |
f438acdf | 1322 | * a certain GPIO line to be used for IRQs. |
d468bf9e | 1323 | */ |
d74be6df | 1324 | int gpio_lock_as_irq(struct gpio_chip *chip, unsigned int offset) |
372e722e | 1325 | { |
d74be6df | 1326 | if (offset >= chip->ngpio) |
d468bf9e LW |
1327 | return -EINVAL; |
1328 | ||
d74be6df AC |
1329 | if (test_bit(FLAG_IS_OUT, &chip->desc[offset].flags)) { |
1330 | chip_err(chip, | |
d468bf9e LW |
1331 | "%s: tried to flag a GPIO set as output for IRQ\n", |
1332 | __func__); | |
1333 | return -EIO; | |
1334 | } | |
1335 | ||
d74be6df | 1336 | set_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags); |
d468bf9e | 1337 | return 0; |
372e722e | 1338 | } |
d74be6df | 1339 | EXPORT_SYMBOL_GPL(gpio_lock_as_irq); |
d2876d08 | 1340 | |
d468bf9e | 1341 | /** |
d74be6df AC |
1342 | * gpio_unlock_as_irq() - unlock a GPIO used as IRQ |
1343 | * @chip: the chip the GPIO to lock belongs to | |
1344 | * @offset: the offset of the GPIO to lock as IRQ | |
d468bf9e LW |
1345 | * |
1346 | * This is used directly by GPIO drivers that want to indicate | |
1347 | * that a certain GPIO is no longer used exclusively for IRQ. | |
d2876d08 | 1348 | */ |
d74be6df | 1349 | void gpio_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) |
d468bf9e | 1350 | { |
d74be6df | 1351 | if (offset >= chip->ngpio) |
d468bf9e | 1352 | return; |
d2876d08 | 1353 | |
d74be6df | 1354 | clear_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags); |
d468bf9e | 1355 | } |
d74be6df | 1356 | EXPORT_SYMBOL_GPL(gpio_unlock_as_irq); |
d468bf9e | 1357 | |
79a9becd AC |
1358 | /** |
1359 | * gpiod_get_raw_value_cansleep() - return a gpio's raw value | |
1360 | * @desc: gpio whose value will be returned | |
1361 | * | |
1362 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding | |
1363 | * its ACTIVE_LOW status. | |
1364 | * | |
1365 | * This function is to be called from contexts that can sleep. | |
d2876d08 | 1366 | */ |
79a9becd | 1367 | int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) |
d2876d08 | 1368 | { |
d2876d08 | 1369 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1370 | if (!desc) |
1371 | return 0; | |
79a9becd | 1372 | return _gpiod_get_raw_value(desc); |
d2876d08 | 1373 | } |
79a9becd | 1374 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); |
372e722e | 1375 | |
79a9becd AC |
1376 | /** |
1377 | * gpiod_get_value_cansleep() - return a gpio's value | |
1378 | * @desc: gpio whose value will be returned | |
1379 | * | |
1380 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
1381 | * account. | |
1382 | * | |
1383 | * This function is to be called from contexts that can sleep. | |
1384 | */ | |
1385 | int gpiod_get_value_cansleep(const struct gpio_desc *desc) | |
d2876d08 | 1386 | { |
3f397c21 | 1387 | int value; |
d2876d08 DB |
1388 | |
1389 | might_sleep_if(extra_checks); | |
bcabdef1 AC |
1390 | if (!desc) |
1391 | return 0; | |
79a9becd AC |
1392 | |
1393 | value = _gpiod_get_raw_value(desc); | |
1394 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1395 | value = !value; | |
1396 | ||
3f397c21 | 1397 | return value; |
d2876d08 | 1398 | } |
79a9becd | 1399 | EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); |
372e722e | 1400 | |
79a9becd AC |
1401 | /** |
1402 | * gpiod_set_raw_value_cansleep() - assign a gpio's raw value | |
1403 | * @desc: gpio whose value will be assigned | |
1404 | * @value: value to assign | |
1405 | * | |
1406 | * Set the raw value of the GPIO, i.e. the value of its physical line without | |
1407 | * regard for its ACTIVE_LOW status. | |
1408 | * | |
1409 | * This function is to be called from contexts that can sleep. | |
1410 | */ | |
1411 | void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) | |
372e722e | 1412 | { |
d2876d08 | 1413 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1414 | if (!desc) |
1415 | return; | |
79a9becd | 1416 | _gpiod_set_raw_value(desc, value); |
372e722e | 1417 | } |
79a9becd | 1418 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); |
d2876d08 | 1419 | |
79a9becd AC |
1420 | /** |
1421 | * gpiod_set_value_cansleep() - assign a gpio's value | |
1422 | * @desc: gpio whose value will be assigned | |
1423 | * @value: value to assign | |
1424 | * | |
1425 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1426 | * account | |
1427 | * | |
1428 | * This function is to be called from contexts that can sleep. | |
1429 | */ | |
1430 | void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) | |
d2876d08 | 1431 | { |
d2876d08 | 1432 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1433 | if (!desc) |
1434 | return; | |
79a9becd AC |
1435 | |
1436 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1437 | value = !value; | |
1438 | _gpiod_set_raw_value(desc, value); | |
372e722e | 1439 | } |
79a9becd | 1440 | EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); |
d2876d08 | 1441 | |
bae48da2 | 1442 | /** |
ad824783 AC |
1443 | * gpiod_add_lookup_table() - register GPIO device consumers |
1444 | * @table: table of consumers to register | |
bae48da2 | 1445 | */ |
ad824783 | 1446 | void gpiod_add_lookup_table(struct gpiod_lookup_table *table) |
bae48da2 AC |
1447 | { |
1448 | mutex_lock(&gpio_lookup_lock); | |
1449 | ||
ad824783 | 1450 | list_add_tail(&table->list, &gpio_lookup_list); |
bae48da2 AC |
1451 | |
1452 | mutex_unlock(&gpio_lookup_lock); | |
1453 | } | |
1454 | ||
bae48da2 | 1455 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, |
53e7cac3 AC |
1456 | unsigned int idx, |
1457 | enum gpio_lookup_flags *flags) | |
bae48da2 | 1458 | { |
dd34c37a | 1459 | static const char *suffixes[] = { "gpios", "gpio" }; |
bae48da2 AC |
1460 | char prop_name[32]; /* 32 is max size of property name */ |
1461 | enum of_gpio_flags of_flags; | |
1462 | struct gpio_desc *desc; | |
dd34c37a | 1463 | unsigned int i; |
bae48da2 | 1464 | |
dd34c37a TR |
1465 | for (i = 0; i < ARRAY_SIZE(suffixes); i++) { |
1466 | if (con_id) | |
1467 | snprintf(prop_name, 32, "%s-%s", con_id, suffixes[i]); | |
1468 | else | |
1469 | snprintf(prop_name, 32, "%s", suffixes[i]); | |
bae48da2 | 1470 | |
dd34c37a TR |
1471 | desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx, |
1472 | &of_flags); | |
06fc3b70 | 1473 | if (!IS_ERR(desc) || (PTR_ERR(desc) == -EPROBE_DEFER)) |
dd34c37a TR |
1474 | break; |
1475 | } | |
bae48da2 AC |
1476 | |
1477 | if (IS_ERR(desc)) | |
1478 | return desc; | |
1479 | ||
1480 | if (of_flags & OF_GPIO_ACTIVE_LOW) | |
53e7cac3 | 1481 | *flags |= GPIO_ACTIVE_LOW; |
bae48da2 AC |
1482 | |
1483 | return desc; | |
1484 | } | |
d2876d08 | 1485 | |
81f59e9d | 1486 | static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id, |
53e7cac3 AC |
1487 | unsigned int idx, |
1488 | enum gpio_lookup_flags *flags) | |
372e722e | 1489 | { |
e01f440a MW |
1490 | struct acpi_gpio_info info; |
1491 | struct gpio_desc *desc; | |
1492 | ||
1493 | desc = acpi_get_gpiod_by_index(dev, idx, &info); | |
1494 | if (IS_ERR(desc)) | |
1495 | return desc; | |
1496 | ||
1497 | if (info.gpioint && info.active_low) | |
53e7cac3 | 1498 | *flags |= GPIO_ACTIVE_LOW; |
e01f440a MW |
1499 | |
1500 | return desc; | |
81f59e9d MW |
1501 | } |
1502 | ||
ad824783 | 1503 | static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) |
bae48da2 AC |
1504 | { |
1505 | const char *dev_id = dev ? dev_name(dev) : NULL; | |
ad824783 | 1506 | struct gpiod_lookup_table *table; |
bae48da2 AC |
1507 | |
1508 | mutex_lock(&gpio_lookup_lock); | |
1509 | ||
ad824783 AC |
1510 | list_for_each_entry(table, &gpio_lookup_list, list) { |
1511 | if (table->dev_id && dev_id) { | |
1512 | /* | |
1513 | * Valid strings on both ends, must be identical to have | |
1514 | * a match | |
1515 | */ | |
1516 | if (!strcmp(table->dev_id, dev_id)) | |
1517 | goto found; | |
1518 | } else { | |
1519 | /* | |
1520 | * One of the pointers is NULL, so both must be to have | |
1521 | * a match | |
1522 | */ | |
1523 | if (dev_id == table->dev_id) | |
1524 | goto found; | |
1525 | } | |
1526 | } | |
1527 | table = NULL; | |
bae48da2 | 1528 | |
ad824783 AC |
1529 | found: |
1530 | mutex_unlock(&gpio_lookup_lock); | |
1531 | return table; | |
1532 | } | |
bae48da2 | 1533 | |
ad824783 AC |
1534 | static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, |
1535 | unsigned int idx, | |
1536 | enum gpio_lookup_flags *flags) | |
1537 | { | |
2a3cf6a3 | 1538 | struct gpio_desc *desc = ERR_PTR(-ENOENT); |
ad824783 AC |
1539 | struct gpiod_lookup_table *table; |
1540 | struct gpiod_lookup *p; | |
bae48da2 | 1541 | |
ad824783 AC |
1542 | table = gpiod_find_lookup_table(dev); |
1543 | if (!table) | |
1544 | return desc; | |
bae48da2 | 1545 | |
ad824783 AC |
1546 | for (p = &table->table[0]; p->chip_label; p++) { |
1547 | struct gpio_chip *chip; | |
bae48da2 | 1548 | |
ad824783 | 1549 | /* idx must always match exactly */ |
bae48da2 AC |
1550 | if (p->idx != idx) |
1551 | continue; | |
1552 | ||
ad824783 AC |
1553 | /* If the lookup entry has a con_id, require exact match */ |
1554 | if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) | |
1555 | continue; | |
bae48da2 | 1556 | |
ad824783 | 1557 | chip = find_chip_by_name(p->chip_label); |
bae48da2 | 1558 | |
ad824783 | 1559 | if (!chip) { |
2a3cf6a3 AC |
1560 | dev_err(dev, "cannot find GPIO chip %s\n", |
1561 | p->chip_label); | |
1562 | return ERR_PTR(-ENODEV); | |
ad824783 | 1563 | } |
bae48da2 | 1564 | |
ad824783 | 1565 | if (chip->ngpio <= p->chip_hwnum) { |
2a3cf6a3 AC |
1566 | dev_err(dev, |
1567 | "requested GPIO %d is out of range [0..%d] for chip %s\n", | |
1568 | idx, chip->ngpio, chip->label); | |
1569 | return ERR_PTR(-EINVAL); | |
bae48da2 | 1570 | } |
bae48da2 | 1571 | |
bb1e88cc | 1572 | desc = gpiochip_get_desc(chip, p->chip_hwnum); |
ad824783 | 1573 | *flags = p->flags; |
bae48da2 | 1574 | |
2a3cf6a3 | 1575 | return desc; |
bae48da2 AC |
1576 | } |
1577 | ||
bae48da2 AC |
1578 | return desc; |
1579 | } | |
1580 | ||
1581 | /** | |
0879162f | 1582 | * gpiod_get - obtain a GPIO for a given GPIO function |
ad824783 | 1583 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 | 1584 | * @con_id: function within the GPIO consumer |
39b2bbe3 | 1585 | * @flags: optional GPIO initialization flags |
bae48da2 AC |
1586 | * |
1587 | * Return the GPIO descriptor corresponding to the function con_id of device | |
2a3cf6a3 AC |
1588 | * dev, -ENOENT if no GPIO has been assigned to the requested function, or |
1589 | * another IS_ERR() code if an error occured while trying to acquire the GPIO. | |
bae48da2 | 1590 | */ |
39b2bbe3 AC |
1591 | struct gpio_desc *__must_check __gpiod_get(struct device *dev, const char *con_id, |
1592 | enum gpiod_flags flags) | |
bae48da2 | 1593 | { |
39b2bbe3 | 1594 | return gpiod_get_index(dev, con_id, 0, flags); |
bae48da2 | 1595 | } |
39b2bbe3 | 1596 | EXPORT_SYMBOL_GPL(__gpiod_get); |
bae48da2 | 1597 | |
29a1f233 TR |
1598 | /** |
1599 | * gpiod_get_optional - obtain an optional GPIO for a given GPIO function | |
1600 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
1601 | * @con_id: function within the GPIO consumer | |
39b2bbe3 | 1602 | * @flags: optional GPIO initialization flags |
29a1f233 TR |
1603 | * |
1604 | * This is equivalent to gpiod_get(), except that when no GPIO was assigned to | |
1605 | * the requested function it will return NULL. This is convenient for drivers | |
1606 | * that need to handle optional GPIOs. | |
1607 | */ | |
39b2bbe3 AC |
1608 | struct gpio_desc *__must_check __gpiod_get_optional(struct device *dev, |
1609 | const char *con_id, | |
1610 | enum gpiod_flags flags) | |
29a1f233 | 1611 | { |
39b2bbe3 | 1612 | return gpiod_get_index_optional(dev, con_id, 0, flags); |
29a1f233 | 1613 | } |
39b2bbe3 | 1614 | EXPORT_SYMBOL_GPL(__gpiod_get_optional); |
29a1f233 | 1615 | |
bae48da2 AC |
1616 | /** |
1617 | * gpiod_get_index - obtain a GPIO from a multi-index GPIO function | |
fdd6a5fe | 1618 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 AC |
1619 | * @con_id: function within the GPIO consumer |
1620 | * @idx: index of the GPIO to obtain in the consumer | |
39b2bbe3 | 1621 | * @flags: optional GPIO initialization flags |
bae48da2 AC |
1622 | * |
1623 | * This variant of gpiod_get() allows to access GPIOs other than the first | |
1624 | * defined one for functions that define several GPIOs. | |
1625 | * | |
2a3cf6a3 AC |
1626 | * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the |
1627 | * requested function and/or index, or another IS_ERR() code if an error | |
1628 | * occured while trying to acquire the GPIO. | |
bae48da2 | 1629 | */ |
39b2bbe3 | 1630 | struct gpio_desc *__must_check __gpiod_get_index(struct device *dev, |
bae48da2 | 1631 | const char *con_id, |
39b2bbe3 AC |
1632 | unsigned int idx, |
1633 | enum gpiod_flags flags) | |
bae48da2 | 1634 | { |
35c5d7fd | 1635 | struct gpio_desc *desc = NULL; |
bae48da2 | 1636 | int status; |
39b2bbe3 | 1637 | enum gpio_lookup_flags lookupflags = 0; |
bae48da2 AC |
1638 | |
1639 | dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); | |
1640 | ||
1641 | /* Using device tree? */ | |
1642 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) { | |
1643 | dev_dbg(dev, "using device tree for GPIO lookup\n"); | |
39b2bbe3 | 1644 | desc = of_find_gpio(dev, con_id, idx, &lookupflags); |
81f59e9d MW |
1645 | } else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) { |
1646 | dev_dbg(dev, "using ACPI for GPIO lookup\n"); | |
39b2bbe3 | 1647 | desc = acpi_find_gpio(dev, con_id, idx, &lookupflags); |
35c5d7fd AC |
1648 | } |
1649 | ||
1650 | /* | |
1651 | * Either we are not using DT or ACPI, or their lookup did not return | |
1652 | * a result. In that case, use platform lookup as a fallback. | |
1653 | */ | |
2a3cf6a3 | 1654 | if (!desc || desc == ERR_PTR(-ENOENT)) { |
bae48da2 | 1655 | dev_dbg(dev, "using lookup tables for GPIO lookup"); |
39b2bbe3 | 1656 | desc = gpiod_find(dev, con_id, idx, &lookupflags); |
bae48da2 AC |
1657 | } |
1658 | ||
1659 | if (IS_ERR(desc)) { | |
351cfe0f | 1660 | dev_dbg(dev, "lookup for GPIO %s failed\n", con_id); |
bae48da2 AC |
1661 | return desc; |
1662 | } | |
1663 | ||
1664 | status = gpiod_request(desc, con_id); | |
1665 | ||
1666 | if (status < 0) | |
1667 | return ERR_PTR(status); | |
1668 | ||
39b2bbe3 | 1669 | if (lookupflags & GPIO_ACTIVE_LOW) |
bae48da2 | 1670 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); |
39b2bbe3 | 1671 | if (lookupflags & GPIO_OPEN_DRAIN) |
53e7cac3 | 1672 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); |
39b2bbe3 | 1673 | if (lookupflags & GPIO_OPEN_SOURCE) |
53e7cac3 | 1674 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); |
bae48da2 | 1675 | |
39b2bbe3 AC |
1676 | /* No particular flag request, return here... */ |
1677 | if (flags & GPIOD_FLAGS_BIT_DIR_SET) | |
1678 | return desc; | |
1679 | ||
1680 | /* Process flags */ | |
1681 | if (flags & GPIOD_FLAGS_BIT_DIR_OUT) | |
1682 | status = gpiod_direction_output(desc, | |
1683 | flags & GPIOD_FLAGS_BIT_DIR_VAL); | |
1684 | else | |
1685 | status = gpiod_direction_input(desc); | |
1686 | ||
1687 | if (status < 0) { | |
1688 | dev_dbg(dev, "setup of GPIO %s failed\n", con_id); | |
1689 | gpiod_put(desc); | |
1690 | return ERR_PTR(status); | |
1691 | } | |
1692 | ||
bae48da2 AC |
1693 | return desc; |
1694 | } | |
39b2bbe3 | 1695 | EXPORT_SYMBOL_GPL(__gpiod_get_index); |
bae48da2 | 1696 | |
29a1f233 TR |
1697 | /** |
1698 | * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO | |
1699 | * function | |
1700 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
1701 | * @con_id: function within the GPIO consumer | |
1702 | * @index: index of the GPIO to obtain in the consumer | |
39b2bbe3 | 1703 | * @flags: optional GPIO initialization flags |
29a1f233 TR |
1704 | * |
1705 | * This is equivalent to gpiod_get_index(), except that when no GPIO with the | |
1706 | * specified index was assigned to the requested function it will return NULL. | |
1707 | * This is convenient for drivers that need to handle optional GPIOs. | |
1708 | */ | |
39b2bbe3 | 1709 | struct gpio_desc *__must_check __gpiod_get_index_optional(struct device *dev, |
29a1f233 | 1710 | const char *con_id, |
39b2bbe3 AC |
1711 | unsigned int index, |
1712 | enum gpiod_flags flags) | |
29a1f233 TR |
1713 | { |
1714 | struct gpio_desc *desc; | |
1715 | ||
39b2bbe3 | 1716 | desc = gpiod_get_index(dev, con_id, index, flags); |
29a1f233 TR |
1717 | if (IS_ERR(desc)) { |
1718 | if (PTR_ERR(desc) == -ENOENT) | |
1719 | return NULL; | |
1720 | } | |
1721 | ||
1722 | return desc; | |
1723 | } | |
39b2bbe3 | 1724 | EXPORT_SYMBOL_GPL(__gpiod_get_index_optional); |
29a1f233 | 1725 | |
bae48da2 AC |
1726 | /** |
1727 | * gpiod_put - dispose of a GPIO descriptor | |
1728 | * @desc: GPIO descriptor to dispose of | |
1729 | * | |
1730 | * No descriptor can be used after gpiod_put() has been called on it. | |
1731 | */ | |
1732 | void gpiod_put(struct gpio_desc *desc) | |
1733 | { | |
1734 | gpiod_free(desc); | |
372e722e | 1735 | } |
bae48da2 | 1736 | EXPORT_SYMBOL_GPL(gpiod_put); |
d2876d08 DB |
1737 | |
1738 | #ifdef CONFIG_DEBUG_FS | |
1739 | ||
d2876d08 DB |
1740 | static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip) |
1741 | { | |
1742 | unsigned i; | |
1743 | unsigned gpio = chip->base; | |
6c0b4e6c | 1744 | struct gpio_desc *gdesc = &chip->desc[0]; |
d2876d08 | 1745 | int is_out; |
d468bf9e | 1746 | int is_irq; |
d2876d08 DB |
1747 | |
1748 | for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) { | |
1749 | if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) | |
1750 | continue; | |
1751 | ||
372e722e | 1752 | gpiod_get_direction(gdesc); |
d2876d08 | 1753 | is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); |
d468bf9e LW |
1754 | is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); |
1755 | seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s", | |
d2876d08 DB |
1756 | gpio, gdesc->label, |
1757 | is_out ? "out" : "in ", | |
1758 | chip->get | |
1759 | ? (chip->get(chip, i) ? "hi" : "lo") | |
d468bf9e LW |
1760 | : "? ", |
1761 | is_irq ? "IRQ" : " "); | |
d2876d08 DB |
1762 | seq_printf(s, "\n"); |
1763 | } | |
1764 | } | |
1765 | ||
f9c4a31f | 1766 | static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) |
d2876d08 | 1767 | { |
362432ae | 1768 | unsigned long flags; |
f9c4a31f | 1769 | struct gpio_chip *chip = NULL; |
cb1650d4 | 1770 | loff_t index = *pos; |
d2876d08 | 1771 | |
f9c4a31f | 1772 | s->private = ""; |
d2876d08 | 1773 | |
362432ae | 1774 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 | 1775 | list_for_each_entry(chip, &gpio_chips, list) |
362432ae GL |
1776 | if (index-- == 0) { |
1777 | spin_unlock_irqrestore(&gpio_lock, flags); | |
cb1650d4 | 1778 | return chip; |
f9c4a31f | 1779 | } |
362432ae | 1780 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f | 1781 | |
cb1650d4 | 1782 | return NULL; |
f9c4a31f TR |
1783 | } |
1784 | ||
1785 | static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
1786 | { | |
362432ae | 1787 | unsigned long flags; |
f9c4a31f | 1788 | struct gpio_chip *chip = v; |
f9c4a31f TR |
1789 | void *ret = NULL; |
1790 | ||
362432ae | 1791 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 AC |
1792 | if (list_is_last(&chip->list, &gpio_chips)) |
1793 | ret = NULL; | |
1794 | else | |
1795 | ret = list_entry(chip->list.next, struct gpio_chip, list); | |
362432ae | 1796 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f TR |
1797 | |
1798 | s->private = "\n"; | |
1799 | ++*pos; | |
1800 | ||
1801 | return ret; | |
1802 | } | |
1803 | ||
1804 | static void gpiolib_seq_stop(struct seq_file *s, void *v) | |
1805 | { | |
1806 | } | |
1807 | ||
1808 | static int gpiolib_seq_show(struct seq_file *s, void *v) | |
1809 | { | |
1810 | struct gpio_chip *chip = v; | |
1811 | struct device *dev; | |
1812 | ||
1813 | seq_printf(s, "%sGPIOs %d-%d", (char *)s->private, | |
1814 | chip->base, chip->base + chip->ngpio - 1); | |
1815 | dev = chip->dev; | |
1816 | if (dev) | |
1817 | seq_printf(s, ", %s/%s", dev->bus ? dev->bus->name : "no-bus", | |
1818 | dev_name(dev)); | |
1819 | if (chip->label) | |
1820 | seq_printf(s, ", %s", chip->label); | |
1821 | if (chip->can_sleep) | |
1822 | seq_printf(s, ", can sleep"); | |
1823 | seq_printf(s, ":\n"); | |
1824 | ||
1825 | if (chip->dbg_show) | |
1826 | chip->dbg_show(s, chip); | |
1827 | else | |
1828 | gpiolib_dbg_show(s, chip); | |
1829 | ||
d2876d08 DB |
1830 | return 0; |
1831 | } | |
1832 | ||
f9c4a31f TR |
1833 | static const struct seq_operations gpiolib_seq_ops = { |
1834 | .start = gpiolib_seq_start, | |
1835 | .next = gpiolib_seq_next, | |
1836 | .stop = gpiolib_seq_stop, | |
1837 | .show = gpiolib_seq_show, | |
1838 | }; | |
1839 | ||
d2876d08 DB |
1840 | static int gpiolib_open(struct inode *inode, struct file *file) |
1841 | { | |
f9c4a31f | 1842 | return seq_open(file, &gpiolib_seq_ops); |
d2876d08 DB |
1843 | } |
1844 | ||
828c0950 | 1845 | static const struct file_operations gpiolib_operations = { |
f9c4a31f | 1846 | .owner = THIS_MODULE, |
d2876d08 DB |
1847 | .open = gpiolib_open, |
1848 | .read = seq_read, | |
1849 | .llseek = seq_lseek, | |
f9c4a31f | 1850 | .release = seq_release, |
d2876d08 DB |
1851 | }; |
1852 | ||
1853 | static int __init gpiolib_debugfs_init(void) | |
1854 | { | |
1855 | /* /sys/kernel/debug/gpio */ | |
1856 | (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO, | |
1857 | NULL, NULL, &gpiolib_operations); | |
1858 | return 0; | |
1859 | } | |
1860 | subsys_initcall(gpiolib_debugfs_init); | |
1861 | ||
1862 | #endif /* DEBUG_FS */ |