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> |
d2876d08 | 17 | |
664e3e5a MW |
18 | #include "gpiolib.h" |
19 | ||
3f397c21 UKK |
20 | #define CREATE_TRACE_POINTS |
21 | #include <trace/events/gpio.h> | |
d2876d08 | 22 | |
79a9becd | 23 | /* Implementation infrastructure for GPIO interfaces. |
d2876d08 | 24 | * |
79a9becd AC |
25 | * The GPIO programming interface allows for inlining speed-critical |
26 | * get/set operations for common cases, so that access to SOC-integrated | |
27 | * GPIOs can sometimes cost only an instruction or two per bit. | |
d2876d08 DB |
28 | */ |
29 | ||
30 | ||
31 | /* When debugging, extend minimal trust to callers and platform code. | |
32 | * Also emit diagnostic messages that may help initial bringup, when | |
33 | * board setup or driver bugs are most common. | |
34 | * | |
35 | * Otherwise, minimize overhead in what may be bitbanging codepaths. | |
36 | */ | |
37 | #ifdef DEBUG | |
38 | #define extra_checks 1 | |
39 | #else | |
40 | #define extra_checks 0 | |
41 | #endif | |
42 | ||
43 | /* gpio_lock prevents conflicts during gpio_desc[] table updates. | |
44 | * While any GPIO is requested, its gpio_chip is not removable; | |
45 | * each GPIO's "requested" flag serves as a lock and refcount. | |
46 | */ | |
47 | static DEFINE_SPINLOCK(gpio_lock); | |
48 | ||
49 | struct gpio_desc { | |
50 | struct gpio_chip *chip; | |
51 | unsigned long flags; | |
52 | /* flag symbols are bit numbers */ | |
53 | #define FLAG_REQUESTED 0 | |
54 | #define FLAG_IS_OUT 1 | |
710b40ea AC |
55 | #define FLAG_EXPORT 2 /* protected by sysfs_lock */ |
56 | #define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */ | |
57 | #define FLAG_TRIG_FALL 4 /* trigger on falling edge */ | |
58 | #define FLAG_TRIG_RISE 5 /* trigger on rising edge */ | |
79a9becd | 59 | #define FLAG_ACTIVE_LOW 6 /* value has active low */ |
710b40ea AC |
60 | #define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */ |
61 | #define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */ | |
d468bf9e | 62 | #define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */ |
ff77c352 | 63 | |
5ba1821d | 64 | #define ID_SHIFT 16 /* add new flags before this one */ |
ff77c352 | 65 | |
5ba1821d | 66 | #define GPIO_FLAGS_MASK ((1 << ID_SHIFT) - 1) |
ff77c352 | 67 | #define GPIO_TRIGGER_MASK (BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE)) |
d2876d08 DB |
68 | |
69 | #ifdef CONFIG_DEBUG_FS | |
70 | const char *label; | |
71 | #endif | |
72 | }; | |
73 | static struct gpio_desc gpio_desc[ARCH_NR_GPIOS]; | |
74 | ||
6c0b4e6c AC |
75 | #define GPIO_OFFSET_VALID(chip, offset) (offset >= 0 && offset < chip->ngpio) |
76 | ||
bae48da2 AC |
77 | static DEFINE_MUTEX(gpio_lookup_lock); |
78 | static LIST_HEAD(gpio_lookup_list); | |
1a989d0f AC |
79 | static LIST_HEAD(gpio_chips); |
80 | ||
ff77c352 | 81 | #ifdef CONFIG_GPIO_SYSFS |
5ba1821d | 82 | static DEFINE_IDR(dirent_idr); |
ff77c352 DG |
83 | #endif |
84 | ||
372e722e AC |
85 | static int gpiod_request(struct gpio_desc *desc, const char *label); |
86 | static void gpiod_free(struct gpio_desc *desc); | |
372e722e | 87 | |
1a2a99c6 AS |
88 | /* With descriptor prefix */ |
89 | ||
7b17b59f | 90 | #ifdef CONFIG_DEBUG_FS |
7589e59f AS |
91 | #define gpiod_emerg(desc, fmt, ...) \ |
92 | pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\ | |
7b17b59f | 93 | ##__VA_ARGS__) |
7589e59f AS |
94 | #define gpiod_crit(desc, fmt, ...) \ |
95 | pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ | |
7b17b59f | 96 | ##__VA_ARGS__) |
7589e59f AS |
97 | #define gpiod_err(desc, fmt, ...) \ |
98 | pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ | |
7b17b59f | 99 | ##__VA_ARGS__) |
7589e59f AS |
100 | #define gpiod_warn(desc, fmt, ...) \ |
101 | pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ | |
7b17b59f | 102 | ##__VA_ARGS__) |
7589e59f AS |
103 | #define gpiod_info(desc, fmt, ...) \ |
104 | pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ | |
7b17b59f | 105 | ##__VA_ARGS__) |
7589e59f AS |
106 | #define gpiod_dbg(desc, fmt, ...) \ |
107 | pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\ | |
7b17b59f MB |
108 | ##__VA_ARGS__) |
109 | #else | |
7589e59f | 110 | #define gpiod_emerg(desc, fmt, ...) \ |
6424de5a | 111 | pr_emerg("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
7589e59f | 112 | #define gpiod_crit(desc, fmt, ...) \ |
6424de5a | 113 | pr_crit("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
7589e59f | 114 | #define gpiod_err(desc, fmt, ...) \ |
6424de5a | 115 | pr_err("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
7589e59f | 116 | #define gpiod_warn(desc, fmt, ...) \ |
6424de5a | 117 | pr_warn("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
7589e59f | 118 | #define gpiod_info(desc, fmt, ...) \ |
6424de5a | 119 | pr_info("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
7589e59f | 120 | #define gpiod_dbg(desc, fmt, ...) \ |
6424de5a | 121 | pr_debug("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
7b17b59f | 122 | #endif |
372e722e | 123 | |
1a2a99c6 AS |
124 | /* With chip prefix */ |
125 | ||
126 | #define chip_emerg(chip, fmt, ...) \ | |
127 | pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) | |
128 | #define chip_crit(chip, fmt, ...) \ | |
129 | pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) | |
130 | #define chip_err(chip, fmt, ...) \ | |
131 | pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) | |
132 | #define chip_warn(chip, fmt, ...) \ | |
133 | pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) | |
134 | #define chip_info(chip, fmt, ...) \ | |
135 | pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) | |
136 | #define chip_dbg(chip, fmt, ...) \ | |
137 | pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) | |
138 | ||
d2876d08 DB |
139 | static inline void desc_set_label(struct gpio_desc *d, const char *label) |
140 | { | |
141 | #ifdef CONFIG_DEBUG_FS | |
142 | d->label = label; | |
143 | #endif | |
144 | } | |
145 | ||
372e722e AC |
146 | /* |
147 | * Return the GPIO number of the passed descriptor relative to its chip | |
148 | */ | |
149 | static int gpio_chip_hwgpio(const struct gpio_desc *desc) | |
150 | { | |
6c0b4e6c | 151 | return desc - &desc->chip->desc[0]; |
372e722e AC |
152 | } |
153 | ||
154 | /** | |
155 | * Convert a GPIO number to its descriptor | |
156 | */ | |
79a9becd | 157 | struct gpio_desc *gpio_to_desc(unsigned gpio) |
372e722e AC |
158 | { |
159 | if (WARN(!gpio_is_valid(gpio), "invalid GPIO %d\n", gpio)) | |
160 | return NULL; | |
161 | else | |
162 | return &gpio_desc[gpio]; | |
163 | } | |
79a9becd | 164 | EXPORT_SYMBOL_GPL(gpio_to_desc); |
372e722e | 165 | |
d468bf9e | 166 | /** |
bb1e88cc | 167 | * Get the GPIO descriptor corresponding to the given hw number for this chip. |
d468bf9e | 168 | */ |
bb1e88cc AC |
169 | struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, |
170 | u16 hwnum) | |
d468bf9e | 171 | { |
bb1e88cc | 172 | if (hwnum >= chip->ngpio) |
b7d0a28a | 173 | return ERR_PTR(-EINVAL); |
d468bf9e | 174 | |
bb1e88cc | 175 | return &chip->desc[hwnum]; |
d468bf9e | 176 | } |
bb1e88cc | 177 | EXPORT_SYMBOL_GPL(gpiochip_get_desc); |
372e722e AC |
178 | |
179 | /** | |
180 | * Convert a GPIO descriptor to the integer namespace. | |
181 | * This should disappear in the future but is needed since we still | |
182 | * use GPIO numbers for error messages and sysfs nodes | |
183 | */ | |
79a9becd | 184 | int desc_to_gpio(const struct gpio_desc *desc) |
372e722e | 185 | { |
8c0fca81 | 186 | return desc - &gpio_desc[0]; |
372e722e | 187 | } |
79a9becd | 188 | EXPORT_SYMBOL_GPL(desc_to_gpio); |
372e722e AC |
189 | |
190 | ||
d2876d08 DB |
191 | /* Warn when drivers omit gpio_request() calls -- legal but ill-advised |
192 | * when setting direction, and otherwise illegal. Until board setup code | |
193 | * and drivers use explicit requests everywhere (which won't happen when | |
194 | * those calls have no teeth) we can't avoid autorequesting. This nag | |
35e8bb51 DB |
195 | * message should motivate switching to explicit requests... so should |
196 | * the weaker cleanup after faults, compared to gpio_request(). | |
8a0cecff DB |
197 | * |
198 | * NOTE: the autorequest mechanism is going away; at this point it's | |
199 | * only "legal" in the sense that (old) code using it won't break yet, | |
200 | * but instead only triggers a WARN() stack dump. | |
d2876d08 | 201 | */ |
372e722e | 202 | static int gpio_ensure_requested(struct gpio_desc *desc) |
d2876d08 | 203 | { |
8a0cecff | 204 | const struct gpio_chip *chip = desc->chip; |
372e722e | 205 | const int gpio = desc_to_gpio(desc); |
35e8bb51 | 206 | |
8a0cecff DB |
207 | if (WARN(test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0, |
208 | "autorequest GPIO-%d\n", gpio)) { | |
35e8bb51 | 209 | if (!try_module_get(chip->owner)) { |
7589e59f AS |
210 | gpiod_err(desc, "%s: module can't be gotten\n", |
211 | __func__); | |
35e8bb51 DB |
212 | clear_bit(FLAG_REQUESTED, &desc->flags); |
213 | /* lose */ | |
214 | return -EIO; | |
215 | } | |
d2876d08 | 216 | desc_set_label(desc, "[auto]"); |
35e8bb51 DB |
217 | /* caller must chip->request() w/o spinlock */ |
218 | if (chip->request) | |
219 | return 1; | |
d2876d08 | 220 | } |
35e8bb51 | 221 | return 0; |
d2876d08 DB |
222 | } |
223 | ||
79a9becd AC |
224 | /** |
225 | * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs | |
226 | * @desc: descriptor to return the chip of | |
227 | */ | |
228 | struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) | |
372e722e | 229 | { |
bcabdef1 | 230 | return desc ? desc->chip : NULL; |
372e722e | 231 | } |
79a9becd | 232 | EXPORT_SYMBOL_GPL(gpiod_to_chip); |
d2876d08 | 233 | |
8d0aab2f AV |
234 | /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ |
235 | static int gpiochip_find_base(int ngpio) | |
236 | { | |
83cabe33 AC |
237 | struct gpio_chip *chip; |
238 | int base = ARCH_NR_GPIOS - ngpio; | |
8d0aab2f | 239 | |
83cabe33 AC |
240 | list_for_each_entry_reverse(chip, &gpio_chips, list) { |
241 | /* found a free space? */ | |
242 | if (chip->base + chip->ngpio <= base) | |
243 | break; | |
244 | else | |
245 | /* nope, check the space right before the chip */ | |
246 | base = chip->base - ngpio; | |
8d0aab2f AV |
247 | } |
248 | ||
83cabe33 | 249 | if (gpio_is_valid(base)) { |
8d0aab2f | 250 | pr_debug("%s: found new base at %d\n", __func__, base); |
83cabe33 AC |
251 | return base; |
252 | } else { | |
253 | pr_err("%s: cannot find free range\n", __func__); | |
254 | return -ENOSPC; | |
169b6a7a | 255 | } |
169b6a7a AV |
256 | } |
257 | ||
79a9becd AC |
258 | /** |
259 | * gpiod_get_direction - return the current direction of a GPIO | |
260 | * @desc: GPIO to get the direction of | |
261 | * | |
262 | * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error. | |
263 | * | |
264 | * This function may sleep if gpiod_cansleep() is true. | |
265 | */ | |
266 | int gpiod_get_direction(const struct gpio_desc *desc) | |
80b0a602 MN |
267 | { |
268 | struct gpio_chip *chip; | |
372e722e | 269 | unsigned offset; |
80b0a602 MN |
270 | int status = -EINVAL; |
271 | ||
372e722e AC |
272 | chip = gpiod_to_chip(desc); |
273 | offset = gpio_chip_hwgpio(desc); | |
80b0a602 MN |
274 | |
275 | if (!chip->get_direction) | |
276 | return status; | |
277 | ||
372e722e | 278 | status = chip->get_direction(chip, offset); |
80b0a602 MN |
279 | if (status > 0) { |
280 | /* GPIOF_DIR_IN, or other positive */ | |
281 | status = 1; | |
def63433 AC |
282 | /* FLAG_IS_OUT is just a cache of the result of get_direction(), |
283 | * so it does not affect constness per se */ | |
284 | clear_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); | |
80b0a602 MN |
285 | } |
286 | if (status == 0) { | |
287 | /* GPIOF_DIR_OUT */ | |
def63433 | 288 | set_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); |
80b0a602 MN |
289 | } |
290 | return status; | |
291 | } | |
79a9becd | 292 | EXPORT_SYMBOL_GPL(gpiod_get_direction); |
80b0a602 | 293 | |
d8f388d8 DB |
294 | #ifdef CONFIG_GPIO_SYSFS |
295 | ||
296 | /* lock protects against unexport_gpio() being called while | |
297 | * sysfs files are active. | |
298 | */ | |
299 | static DEFINE_MUTEX(sysfs_lock); | |
300 | ||
301 | /* | |
302 | * /sys/class/gpio/gpioN... only for GPIOs that are exported | |
303 | * /direction | |
304 | * * MAY BE OMITTED if kernel won't allow direction changes | |
305 | * * is read/write as "in" or "out" | |
306 | * * may also be written as "high" or "low", initializing | |
307 | * output value as specified ("out" implies "low") | |
308 | * /value | |
309 | * * always readable, subject to hardware behavior | |
310 | * * may be writable, as zero/nonzero | |
ff77c352 DG |
311 | * /edge |
312 | * * configures behavior of poll(2) on /value | |
313 | * * available only if pin can generate IRQs on input | |
314 | * * is read/write as "none", "falling", "rising", or "both" | |
07697461 JN |
315 | * /active_low |
316 | * * configures polarity of /value | |
317 | * * is read/write as zero/nonzero | |
318 | * * also affects existing and subsequent "falling" and "rising" | |
319 | * /edge configuration | |
d8f388d8 DB |
320 | */ |
321 | ||
322 | static ssize_t gpio_direction_show(struct device *dev, | |
323 | struct device_attribute *attr, char *buf) | |
324 | { | |
def63433 | 325 | const struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
326 | ssize_t status; |
327 | ||
328 | mutex_lock(&sysfs_lock); | |
329 | ||
476171ce | 330 | if (!test_bit(FLAG_EXPORT, &desc->flags)) { |
d8f388d8 | 331 | status = -EIO; |
476171ce | 332 | } else { |
372e722e | 333 | gpiod_get_direction(desc); |
d8f388d8 DB |
334 | status = sprintf(buf, "%s\n", |
335 | test_bit(FLAG_IS_OUT, &desc->flags) | |
336 | ? "out" : "in"); | |
476171ce | 337 | } |
d8f388d8 DB |
338 | |
339 | mutex_unlock(&sysfs_lock); | |
340 | return status; | |
341 | } | |
342 | ||
343 | static ssize_t gpio_direction_store(struct device *dev, | |
344 | struct device_attribute *attr, const char *buf, size_t size) | |
345 | { | |
372e722e | 346 | struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
347 | ssize_t status; |
348 | ||
349 | mutex_lock(&sysfs_lock); | |
350 | ||
351 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
352 | status = -EIO; | |
353 | else if (sysfs_streq(buf, "high")) | |
ef70bbe1 | 354 | status = gpiod_direction_output_raw(desc, 1); |
d8f388d8 | 355 | else if (sysfs_streq(buf, "out") || sysfs_streq(buf, "low")) |
ef70bbe1 | 356 | status = gpiod_direction_output_raw(desc, 0); |
d8f388d8 | 357 | else if (sysfs_streq(buf, "in")) |
372e722e | 358 | status = gpiod_direction_input(desc); |
d8f388d8 DB |
359 | else |
360 | status = -EINVAL; | |
361 | ||
362 | mutex_unlock(&sysfs_lock); | |
363 | return status ? : size; | |
364 | } | |
365 | ||
07697461 | 366 | static /* const */ DEVICE_ATTR(direction, 0644, |
d8f388d8 DB |
367 | gpio_direction_show, gpio_direction_store); |
368 | ||
369 | static ssize_t gpio_value_show(struct device *dev, | |
370 | struct device_attribute *attr, char *buf) | |
371 | { | |
372e722e | 372 | struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
373 | ssize_t status; |
374 | ||
375 | mutex_lock(&sysfs_lock); | |
376 | ||
79a9becd | 377 | if (!test_bit(FLAG_EXPORT, &desc->flags)) |
d8f388d8 | 378 | status = -EIO; |
79a9becd AC |
379 | else |
380 | status = sprintf(buf, "%d\n", gpiod_get_value_cansleep(desc)); | |
d8f388d8 DB |
381 | |
382 | mutex_unlock(&sysfs_lock); | |
383 | return status; | |
384 | } | |
385 | ||
386 | static ssize_t gpio_value_store(struct device *dev, | |
387 | struct device_attribute *attr, const char *buf, size_t size) | |
388 | { | |
372e722e | 389 | struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
390 | ssize_t status; |
391 | ||
392 | mutex_lock(&sysfs_lock); | |
393 | ||
394 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
395 | status = -EIO; | |
396 | else if (!test_bit(FLAG_IS_OUT, &desc->flags)) | |
397 | status = -EPERM; | |
398 | else { | |
399 | long value; | |
400 | ||
a3d88c92 | 401 | status = kstrtol(buf, 0, &value); |
d8f388d8 | 402 | if (status == 0) { |
79a9becd | 403 | gpiod_set_value_cansleep(desc, value); |
d8f388d8 DB |
404 | status = size; |
405 | } | |
406 | } | |
407 | ||
408 | mutex_unlock(&sysfs_lock); | |
409 | return status; | |
410 | } | |
411 | ||
07697461 | 412 | static const DEVICE_ATTR(value, 0644, |
d8f388d8 DB |
413 | gpio_value_show, gpio_value_store); |
414 | ||
ff77c352 DG |
415 | static irqreturn_t gpio_sysfs_irq(int irq, void *priv) |
416 | { | |
324a56e1 | 417 | struct kernfs_node *value_sd = priv; |
ff77c352 | 418 | |
5ba1821d | 419 | sysfs_notify_dirent(value_sd); |
ff77c352 DG |
420 | return IRQ_HANDLED; |
421 | } | |
422 | ||
ff77c352 DG |
423 | static int gpio_setup_irq(struct gpio_desc *desc, struct device *dev, |
424 | unsigned long gpio_flags) | |
425 | { | |
324a56e1 | 426 | struct kernfs_node *value_sd; |
ff77c352 DG |
427 | unsigned long irq_flags; |
428 | int ret, irq, id; | |
429 | ||
430 | if ((desc->flags & GPIO_TRIGGER_MASK) == gpio_flags) | |
431 | return 0; | |
432 | ||
372e722e | 433 | irq = gpiod_to_irq(desc); |
ff77c352 DG |
434 | if (irq < 0) |
435 | return -EIO; | |
436 | ||
5ba1821d DG |
437 | id = desc->flags >> ID_SHIFT; |
438 | value_sd = idr_find(&dirent_idr, id); | |
439 | if (value_sd) | |
440 | free_irq(irq, value_sd); | |
ff77c352 DG |
441 | |
442 | desc->flags &= ~GPIO_TRIGGER_MASK; | |
443 | ||
444 | if (!gpio_flags) { | |
d468bf9e | 445 | gpiod_unlock_as_irq(desc); |
ff77c352 | 446 | ret = 0; |
5ba1821d | 447 | goto free_id; |
ff77c352 DG |
448 | } |
449 | ||
450 | irq_flags = IRQF_SHARED; | |
451 | if (test_bit(FLAG_TRIG_FALL, &gpio_flags)) | |
07697461 JN |
452 | irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? |
453 | IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING; | |
ff77c352 | 454 | if (test_bit(FLAG_TRIG_RISE, &gpio_flags)) |
07697461 JN |
455 | irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? |
456 | IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING; | |
ff77c352 | 457 | |
5ba1821d | 458 | if (!value_sd) { |
388975cc | 459 | value_sd = sysfs_get_dirent(dev->kobj.sd, "value"); |
5ba1821d DG |
460 | if (!value_sd) { |
461 | ret = -ENODEV; | |
ff77c352 DG |
462 | goto err_out; |
463 | } | |
464 | ||
62f516b8 TH |
465 | ret = idr_alloc(&dirent_idr, value_sd, 1, 0, GFP_KERNEL); |
466 | if (ret < 0) | |
5ba1821d | 467 | goto free_sd; |
62f516b8 | 468 | id = ret; |
ff77c352 DG |
469 | |
470 | desc->flags &= GPIO_FLAGS_MASK; | |
5ba1821d | 471 | desc->flags |= (unsigned long)id << ID_SHIFT; |
ff77c352 | 472 | |
5ba1821d | 473 | if (desc->flags >> ID_SHIFT != id) { |
ff77c352 DG |
474 | ret = -ERANGE; |
475 | goto free_id; | |
476 | } | |
ff77c352 DG |
477 | } |
478 | ||
364fadb3 | 479 | ret = request_any_context_irq(irq, gpio_sysfs_irq, irq_flags, |
5ba1821d | 480 | "gpiolib", value_sd); |
364fadb3 | 481 | if (ret < 0) |
5ba1821d | 482 | goto free_id; |
ff77c352 | 483 | |
d468bf9e LW |
484 | ret = gpiod_lock_as_irq(desc); |
485 | if (ret < 0) { | |
486 | gpiod_warn(desc, "failed to flag the GPIO for IRQ\n"); | |
487 | goto free_id; | |
488 | } | |
489 | ||
ff77c352 DG |
490 | desc->flags |= gpio_flags; |
491 | return 0; | |
492 | ||
ff77c352 | 493 | free_id: |
5ba1821d | 494 | idr_remove(&dirent_idr, id); |
ff77c352 | 495 | desc->flags &= GPIO_FLAGS_MASK; |
5ba1821d DG |
496 | free_sd: |
497 | if (value_sd) | |
498 | sysfs_put(value_sd); | |
ff77c352 DG |
499 | err_out: |
500 | return ret; | |
501 | } | |
502 | ||
503 | static const struct { | |
504 | const char *name; | |
505 | unsigned long flags; | |
506 | } trigger_types[] = { | |
507 | { "none", 0 }, | |
508 | { "falling", BIT(FLAG_TRIG_FALL) }, | |
509 | { "rising", BIT(FLAG_TRIG_RISE) }, | |
510 | { "both", BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE) }, | |
511 | }; | |
512 | ||
513 | static ssize_t gpio_edge_show(struct device *dev, | |
514 | struct device_attribute *attr, char *buf) | |
515 | { | |
516 | const struct gpio_desc *desc = dev_get_drvdata(dev); | |
517 | ssize_t status; | |
518 | ||
519 | mutex_lock(&sysfs_lock); | |
520 | ||
521 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
522 | status = -EIO; | |
523 | else { | |
524 | int i; | |
525 | ||
526 | status = 0; | |
527 | for (i = 0; i < ARRAY_SIZE(trigger_types); i++) | |
528 | if ((desc->flags & GPIO_TRIGGER_MASK) | |
529 | == trigger_types[i].flags) { | |
530 | status = sprintf(buf, "%s\n", | |
531 | trigger_types[i].name); | |
532 | break; | |
533 | } | |
534 | } | |
535 | ||
536 | mutex_unlock(&sysfs_lock); | |
537 | return status; | |
538 | } | |
539 | ||
540 | static ssize_t gpio_edge_store(struct device *dev, | |
541 | struct device_attribute *attr, const char *buf, size_t size) | |
542 | { | |
543 | struct gpio_desc *desc = dev_get_drvdata(dev); | |
544 | ssize_t status; | |
545 | int i; | |
546 | ||
547 | for (i = 0; i < ARRAY_SIZE(trigger_types); i++) | |
548 | if (sysfs_streq(trigger_types[i].name, buf)) | |
549 | goto found; | |
550 | return -EINVAL; | |
551 | ||
552 | found: | |
553 | mutex_lock(&sysfs_lock); | |
554 | ||
555 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
556 | status = -EIO; | |
557 | else { | |
558 | status = gpio_setup_irq(desc, dev, trigger_types[i].flags); | |
559 | if (!status) | |
560 | status = size; | |
561 | } | |
562 | ||
563 | mutex_unlock(&sysfs_lock); | |
564 | ||
565 | return status; | |
566 | } | |
567 | ||
568 | static DEVICE_ATTR(edge, 0644, gpio_edge_show, gpio_edge_store); | |
569 | ||
07697461 JN |
570 | static int sysfs_set_active_low(struct gpio_desc *desc, struct device *dev, |
571 | int value) | |
572 | { | |
573 | int status = 0; | |
574 | ||
575 | if (!!test_bit(FLAG_ACTIVE_LOW, &desc->flags) == !!value) | |
576 | return 0; | |
577 | ||
578 | if (value) | |
579 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
580 | else | |
581 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
582 | ||
583 | /* reconfigure poll(2) support if enabled on one edge only */ | |
584 | if (dev != NULL && (!!test_bit(FLAG_TRIG_RISE, &desc->flags) ^ | |
585 | !!test_bit(FLAG_TRIG_FALL, &desc->flags))) { | |
586 | unsigned long trigger_flags = desc->flags & GPIO_TRIGGER_MASK; | |
587 | ||
588 | gpio_setup_irq(desc, dev, 0); | |
589 | status = gpio_setup_irq(desc, dev, trigger_flags); | |
590 | } | |
591 | ||
592 | return status; | |
593 | } | |
594 | ||
595 | static ssize_t gpio_active_low_show(struct device *dev, | |
596 | struct device_attribute *attr, char *buf) | |
597 | { | |
598 | const struct gpio_desc *desc = dev_get_drvdata(dev); | |
599 | ssize_t status; | |
600 | ||
601 | mutex_lock(&sysfs_lock); | |
602 | ||
603 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
604 | status = -EIO; | |
605 | else | |
606 | status = sprintf(buf, "%d\n", | |
607 | !!test_bit(FLAG_ACTIVE_LOW, &desc->flags)); | |
608 | ||
609 | mutex_unlock(&sysfs_lock); | |
610 | ||
611 | return status; | |
612 | } | |
613 | ||
614 | static ssize_t gpio_active_low_store(struct device *dev, | |
615 | struct device_attribute *attr, const char *buf, size_t size) | |
616 | { | |
617 | struct gpio_desc *desc = dev_get_drvdata(dev); | |
618 | ssize_t status; | |
619 | ||
620 | mutex_lock(&sysfs_lock); | |
621 | ||
622 | if (!test_bit(FLAG_EXPORT, &desc->flags)) { | |
623 | status = -EIO; | |
624 | } else { | |
625 | long value; | |
626 | ||
a3d88c92 | 627 | status = kstrtol(buf, 0, &value); |
07697461 JN |
628 | if (status == 0) |
629 | status = sysfs_set_active_low(desc, dev, value != 0); | |
630 | } | |
631 | ||
632 | mutex_unlock(&sysfs_lock); | |
633 | ||
634 | return status ? : size; | |
635 | } | |
636 | ||
637 | static const DEVICE_ATTR(active_low, 0644, | |
638 | gpio_active_low_show, gpio_active_low_store); | |
639 | ||
d8f388d8 | 640 | static const struct attribute *gpio_attrs[] = { |
d8f388d8 | 641 | &dev_attr_value.attr, |
07697461 | 642 | &dev_attr_active_low.attr, |
d8f388d8 DB |
643 | NULL, |
644 | }; | |
645 | ||
646 | static const struct attribute_group gpio_attr_group = { | |
647 | .attrs = (struct attribute **) gpio_attrs, | |
648 | }; | |
649 | ||
650 | /* | |
651 | * /sys/class/gpio/gpiochipN/ | |
652 | * /base ... matching gpio_chip.base (N) | |
653 | * /label ... matching gpio_chip.label | |
654 | * /ngpio ... matching gpio_chip.ngpio | |
655 | */ | |
656 | ||
657 | static ssize_t chip_base_show(struct device *dev, | |
658 | struct device_attribute *attr, char *buf) | |
659 | { | |
660 | const struct gpio_chip *chip = dev_get_drvdata(dev); | |
661 | ||
662 | return sprintf(buf, "%d\n", chip->base); | |
663 | } | |
664 | static DEVICE_ATTR(base, 0444, chip_base_show, NULL); | |
665 | ||
666 | static ssize_t chip_label_show(struct device *dev, | |
667 | struct device_attribute *attr, char *buf) | |
668 | { | |
669 | const struct gpio_chip *chip = dev_get_drvdata(dev); | |
670 | ||
671 | return sprintf(buf, "%s\n", chip->label ? : ""); | |
672 | } | |
673 | static DEVICE_ATTR(label, 0444, chip_label_show, NULL); | |
674 | ||
675 | static ssize_t chip_ngpio_show(struct device *dev, | |
676 | struct device_attribute *attr, char *buf) | |
677 | { | |
678 | const struct gpio_chip *chip = dev_get_drvdata(dev); | |
679 | ||
680 | return sprintf(buf, "%u\n", chip->ngpio); | |
681 | } | |
682 | static DEVICE_ATTR(ngpio, 0444, chip_ngpio_show, NULL); | |
683 | ||
684 | static const struct attribute *gpiochip_attrs[] = { | |
685 | &dev_attr_base.attr, | |
686 | &dev_attr_label.attr, | |
687 | &dev_attr_ngpio.attr, | |
688 | NULL, | |
689 | }; | |
690 | ||
691 | static const struct attribute_group gpiochip_attr_group = { | |
692 | .attrs = (struct attribute **) gpiochip_attrs, | |
693 | }; | |
694 | ||
695 | /* | |
696 | * /sys/class/gpio/export ... write-only | |
697 | * integer N ... number of GPIO to export (full access) | |
698 | * /sys/class/gpio/unexport ... write-only | |
699 | * integer N ... number of GPIO to unexport | |
700 | */ | |
28812fe1 AK |
701 | static ssize_t export_store(struct class *class, |
702 | struct class_attribute *attr, | |
703 | const char *buf, size_t len) | |
d8f388d8 | 704 | { |
372e722e AC |
705 | long gpio; |
706 | struct gpio_desc *desc; | |
707 | int status; | |
d8f388d8 | 708 | |
a3d88c92 | 709 | status = kstrtol(buf, 0, &gpio); |
d8f388d8 DB |
710 | if (status < 0) |
711 | goto done; | |
712 | ||
372e722e | 713 | desc = gpio_to_desc(gpio); |
bcabdef1 AC |
714 | /* reject invalid GPIOs */ |
715 | if (!desc) { | |
716 | pr_warn("%s: invalid GPIO %ld\n", __func__, gpio); | |
717 | return -EINVAL; | |
718 | } | |
372e722e | 719 | |
d8f388d8 DB |
720 | /* No extra locking here; FLAG_SYSFS just signifies that the |
721 | * request and export were done by on behalf of userspace, so | |
722 | * they may be undone on its behalf too. | |
723 | */ | |
724 | ||
372e722e | 725 | status = gpiod_request(desc, "sysfs"); |
ad2fab36 MN |
726 | if (status < 0) { |
727 | if (status == -EPROBE_DEFER) | |
728 | status = -ENODEV; | |
d8f388d8 | 729 | goto done; |
ad2fab36 | 730 | } |
372e722e | 731 | status = gpiod_export(desc, true); |
d8f388d8 | 732 | if (status < 0) |
372e722e | 733 | gpiod_free(desc); |
d8f388d8 | 734 | else |
372e722e | 735 | set_bit(FLAG_SYSFS, &desc->flags); |
d8f388d8 DB |
736 | |
737 | done: | |
738 | if (status) | |
739 | pr_debug("%s: status %d\n", __func__, status); | |
740 | return status ? : len; | |
741 | } | |
742 | ||
28812fe1 AK |
743 | static ssize_t unexport_store(struct class *class, |
744 | struct class_attribute *attr, | |
745 | const char *buf, size_t len) | |
d8f388d8 | 746 | { |
372e722e AC |
747 | long gpio; |
748 | struct gpio_desc *desc; | |
749 | int status; | |
d8f388d8 | 750 | |
a3d88c92 | 751 | status = kstrtol(buf, 0, &gpio); |
d8f388d8 DB |
752 | if (status < 0) |
753 | goto done; | |
754 | ||
372e722e | 755 | desc = gpio_to_desc(gpio); |
d8f388d8 | 756 | /* reject bogus commands (gpio_unexport ignores them) */ |
bcabdef1 AC |
757 | if (!desc) { |
758 | pr_warn("%s: invalid GPIO %ld\n", __func__, gpio); | |
759 | return -EINVAL; | |
760 | } | |
761 | ||
762 | status = -EINVAL; | |
d8f388d8 DB |
763 | |
764 | /* No extra locking here; FLAG_SYSFS just signifies that the | |
765 | * request and export were done by on behalf of userspace, so | |
766 | * they may be undone on its behalf too. | |
767 | */ | |
372e722e | 768 | if (test_and_clear_bit(FLAG_SYSFS, &desc->flags)) { |
d8f388d8 | 769 | status = 0; |
372e722e | 770 | gpiod_free(desc); |
d8f388d8 DB |
771 | } |
772 | done: | |
773 | if (status) | |
774 | pr_debug("%s: status %d\n", __func__, status); | |
775 | return status ? : len; | |
776 | } | |
777 | ||
778 | static struct class_attribute gpio_class_attrs[] = { | |
779 | __ATTR(export, 0200, NULL, export_store), | |
780 | __ATTR(unexport, 0200, NULL, unexport_store), | |
781 | __ATTR_NULL, | |
782 | }; | |
783 | ||
784 | static struct class gpio_class = { | |
785 | .name = "gpio", | |
786 | .owner = THIS_MODULE, | |
787 | ||
788 | .class_attrs = gpio_class_attrs, | |
789 | }; | |
790 | ||
791 | ||
792 | /** | |
79a9becd | 793 | * gpiod_export - export a GPIO through sysfs |
d8f388d8 DB |
794 | * @gpio: gpio to make available, already requested |
795 | * @direction_may_change: true if userspace may change gpio direction | |
796 | * Context: arch_initcall or later | |
797 | * | |
798 | * When drivers want to make a GPIO accessible to userspace after they | |
799 | * have requested it -- perhaps while debugging, or as part of their | |
800 | * public interface -- they may use this routine. If the GPIO can | |
801 | * change direction (some can't) and the caller allows it, userspace | |
802 | * will see "direction" sysfs attribute which may be used to change | |
803 | * the gpio's direction. A "value" attribute will always be provided. | |
804 | * | |
805 | * Returns zero on success, else an error. | |
806 | */ | |
79a9becd | 807 | int gpiod_export(struct gpio_desc *desc, bool direction_may_change) |
d8f388d8 DB |
808 | { |
809 | unsigned long flags; | |
fc4e2514 | 810 | int status; |
62154991 | 811 | const char *ioname = NULL; |
fc4e2514 | 812 | struct device *dev; |
372e722e | 813 | int offset; |
d8f388d8 DB |
814 | |
815 | /* can't export until sysfs is available ... */ | |
816 | if (!gpio_class.p) { | |
817 | pr_debug("%s: called too early!\n", __func__); | |
818 | return -ENOENT; | |
819 | } | |
820 | ||
372e722e AC |
821 | if (!desc) { |
822 | pr_debug("%s: invalid gpio descriptor\n", __func__); | |
fc4e2514 RM |
823 | return -EINVAL; |
824 | } | |
d8f388d8 DB |
825 | |
826 | mutex_lock(&sysfs_lock); | |
827 | ||
828 | spin_lock_irqsave(&gpio_lock, flags); | |
fc4e2514 RM |
829 | if (!test_bit(FLAG_REQUESTED, &desc->flags) || |
830 | test_bit(FLAG_EXPORT, &desc->flags)) { | |
831 | spin_unlock_irqrestore(&gpio_lock, flags); | |
7589e59f AS |
832 | gpiod_dbg(desc, "%s: unavailable (requested=%d, exported=%d)\n", |
833 | __func__, | |
fc4e2514 RM |
834 | test_bit(FLAG_REQUESTED, &desc->flags), |
835 | test_bit(FLAG_EXPORT, &desc->flags)); | |
529f2ad5 DC |
836 | status = -EPERM; |
837 | goto fail_unlock; | |
d8f388d8 | 838 | } |
fc4e2514 RM |
839 | |
840 | if (!desc->chip->direction_input || !desc->chip->direction_output) | |
841 | direction_may_change = false; | |
d8f388d8 DB |
842 | spin_unlock_irqrestore(&gpio_lock, flags); |
843 | ||
372e722e AC |
844 | offset = gpio_chip_hwgpio(desc); |
845 | if (desc->chip->names && desc->chip->names[offset]) | |
846 | ioname = desc->chip->names[offset]; | |
926b663c | 847 | |
fc4e2514 | 848 | dev = device_create(&gpio_class, desc->chip->dev, MKDEV(0, 0), |
372e722e AC |
849 | desc, ioname ? ioname : "gpio%u", |
850 | desc_to_gpio(desc)); | |
fc4e2514 RM |
851 | if (IS_ERR(dev)) { |
852 | status = PTR_ERR(dev); | |
853 | goto fail_unlock; | |
d8f388d8 DB |
854 | } |
855 | ||
fc4e2514 | 856 | status = sysfs_create_group(&dev->kobj, &gpio_attr_group); |
d8f388d8 | 857 | if (status) |
fc4e2514 | 858 | goto fail_unregister_device; |
d8f388d8 | 859 | |
fc4e2514 RM |
860 | if (direction_may_change) { |
861 | status = device_create_file(dev, &dev_attr_direction); | |
862 | if (status) | |
863 | goto fail_unregister_device; | |
864 | } | |
865 | ||
372e722e | 866 | if (gpiod_to_irq(desc) >= 0 && (direction_may_change || |
fc4e2514 RM |
867 | !test_bit(FLAG_IS_OUT, &desc->flags))) { |
868 | status = device_create_file(dev, &dev_attr_edge); | |
869 | if (status) | |
870 | goto fail_unregister_device; | |
871 | } | |
d8f388d8 | 872 | |
fc4e2514 RM |
873 | set_bit(FLAG_EXPORT, &desc->flags); |
874 | mutex_unlock(&sysfs_lock); | |
875 | return 0; | |
876 | ||
877 | fail_unregister_device: | |
878 | device_unregister(dev); | |
879 | fail_unlock: | |
880 | mutex_unlock(&sysfs_lock); | |
7589e59f | 881 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
d8f388d8 DB |
882 | return status; |
883 | } | |
79a9becd | 884 | EXPORT_SYMBOL_GPL(gpiod_export); |
d8f388d8 | 885 | |
9f3b795a | 886 | static int match_export(struct device *dev, const void *data) |
d8f388d8 DB |
887 | { |
888 | return dev_get_drvdata(dev) == data; | |
889 | } | |
890 | ||
a4177ee7 | 891 | /** |
79a9becd | 892 | * gpiod_export_link - create a sysfs link to an exported GPIO node |
a4177ee7 JN |
893 | * @dev: device under which to create symlink |
894 | * @name: name of the symlink | |
895 | * @gpio: gpio to create symlink to, already exported | |
896 | * | |
897 | * Set up a symlink from /sys/.../dev/name to /sys/class/gpio/gpioN | |
898 | * node. Caller is responsible for unlinking. | |
899 | * | |
900 | * Returns zero on success, else an error. | |
901 | */ | |
79a9becd AC |
902 | int gpiod_export_link(struct device *dev, const char *name, |
903 | struct gpio_desc *desc) | |
a4177ee7 | 904 | { |
a4177ee7 JN |
905 | int status = -EINVAL; |
906 | ||
bcabdef1 AC |
907 | if (!desc) { |
908 | pr_warn("%s: invalid GPIO\n", __func__); | |
909 | return -EINVAL; | |
910 | } | |
a4177ee7 JN |
911 | |
912 | mutex_lock(&sysfs_lock); | |
913 | ||
a4177ee7 JN |
914 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
915 | struct device *tdev; | |
916 | ||
917 | tdev = class_find_device(&gpio_class, NULL, desc, match_export); | |
918 | if (tdev != NULL) { | |
919 | status = sysfs_create_link(&dev->kobj, &tdev->kobj, | |
920 | name); | |
921 | } else { | |
922 | status = -ENODEV; | |
923 | } | |
924 | } | |
925 | ||
926 | mutex_unlock(&sysfs_lock); | |
927 | ||
a4177ee7 | 928 | if (status) |
7589e59f | 929 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
a4177ee7 JN |
930 | |
931 | return status; | |
932 | } | |
79a9becd | 933 | EXPORT_SYMBOL_GPL(gpiod_export_link); |
07697461 JN |
934 | |
935 | /** | |
79a9becd | 936 | * gpiod_sysfs_set_active_low - set the polarity of gpio sysfs value |
07697461 JN |
937 | * @gpio: gpio to change |
938 | * @value: non-zero to use active low, i.e. inverted values | |
939 | * | |
940 | * Set the polarity of /sys/class/gpio/gpioN/value sysfs attribute. | |
941 | * The GPIO does not have to be exported yet. If poll(2) support has | |
942 | * been enabled for either rising or falling edge, it will be | |
943 | * reconfigured to follow the new polarity. | |
944 | * | |
945 | * Returns zero on success, else an error. | |
946 | */ | |
79a9becd | 947 | int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value) |
07697461 | 948 | { |
07697461 JN |
949 | struct device *dev = NULL; |
950 | int status = -EINVAL; | |
951 | ||
bcabdef1 AC |
952 | if (!desc) { |
953 | pr_warn("%s: invalid GPIO\n", __func__); | |
954 | return -EINVAL; | |
955 | } | |
07697461 JN |
956 | |
957 | mutex_lock(&sysfs_lock); | |
958 | ||
07697461 | 959 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
07697461 JN |
960 | dev = class_find_device(&gpio_class, NULL, desc, match_export); |
961 | if (dev == NULL) { | |
962 | status = -ENODEV; | |
963 | goto unlock; | |
964 | } | |
965 | } | |
966 | ||
967 | status = sysfs_set_active_low(desc, dev, value); | |
968 | ||
969 | unlock: | |
970 | mutex_unlock(&sysfs_lock); | |
971 | ||
07697461 | 972 | if (status) |
7589e59f | 973 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
07697461 JN |
974 | |
975 | return status; | |
976 | } | |
79a9becd | 977 | EXPORT_SYMBOL_GPL(gpiod_sysfs_set_active_low); |
07697461 | 978 | |
d8f388d8 | 979 | /** |
79a9becd | 980 | * gpiod_unexport - reverse effect of gpio_export() |
d8f388d8 DB |
981 | * @gpio: gpio to make unavailable |
982 | * | |
983 | * This is implicit on gpio_free(). | |
984 | */ | |
79a9becd | 985 | void gpiod_unexport(struct gpio_desc *desc) |
d8f388d8 | 986 | { |
6a99ad4a | 987 | int status = 0; |
864533ce | 988 | struct device *dev = NULL; |
d8f388d8 | 989 | |
372e722e | 990 | if (!desc) { |
bcabdef1 AC |
991 | pr_warn("%s: invalid GPIO\n", __func__); |
992 | return; | |
6a99ad4a | 993 | } |
d8f388d8 DB |
994 | |
995 | mutex_lock(&sysfs_lock); | |
996 | ||
d8f388d8 | 997 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
d8f388d8 DB |
998 | |
999 | dev = class_find_device(&gpio_class, NULL, desc, match_export); | |
1000 | if (dev) { | |
ff77c352 | 1001 | gpio_setup_irq(desc, dev, 0); |
d8f388d8 | 1002 | clear_bit(FLAG_EXPORT, &desc->flags); |
d8f388d8 DB |
1003 | } else |
1004 | status = -ENODEV; | |
1005 | } | |
1006 | ||
1007 | mutex_unlock(&sysfs_lock); | |
372e722e | 1008 | |
864533ce ML |
1009 | if (dev) { |
1010 | device_unregister(dev); | |
1011 | put_device(dev); | |
1012 | } | |
bcabdef1 | 1013 | |
d8f388d8 | 1014 | if (status) |
7589e59f | 1015 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
372e722e | 1016 | } |
79a9becd | 1017 | EXPORT_SYMBOL_GPL(gpiod_unexport); |
d8f388d8 DB |
1018 | |
1019 | static int gpiochip_export(struct gpio_chip *chip) | |
1020 | { | |
1021 | int status; | |
1022 | struct device *dev; | |
1023 | ||
1024 | /* Many systems register gpio chips for SOC support very early, | |
1025 | * before driver model support is available. In those cases we | |
1026 | * export this later, in gpiolib_sysfs_init() ... here we just | |
1027 | * verify that _some_ field of gpio_class got initialized. | |
1028 | */ | |
1029 | if (!gpio_class.p) | |
1030 | return 0; | |
1031 | ||
1032 | /* use chip->base for the ID; it's already known to be unique */ | |
1033 | mutex_lock(&sysfs_lock); | |
1034 | dev = device_create(&gpio_class, chip->dev, MKDEV(0, 0), chip, | |
1035 | "gpiochip%d", chip->base); | |
d62668e1 | 1036 | if (!IS_ERR(dev)) { |
d8f388d8 DB |
1037 | status = sysfs_create_group(&dev->kobj, |
1038 | &gpiochip_attr_group); | |
1039 | } else | |
d62668e1 | 1040 | status = PTR_ERR(dev); |
d8f388d8 DB |
1041 | chip->exported = (status == 0); |
1042 | mutex_unlock(&sysfs_lock); | |
1043 | ||
1044 | if (status) { | |
1045 | unsigned long flags; | |
1046 | unsigned gpio; | |
1047 | ||
1048 | spin_lock_irqsave(&gpio_lock, flags); | |
6c0b4e6c AC |
1049 | gpio = 0; |
1050 | while (gpio < chip->ngpio) | |
1051 | chip->desc[gpio++].chip = NULL; | |
d8f388d8 DB |
1052 | spin_unlock_irqrestore(&gpio_lock, flags); |
1053 | ||
1a2a99c6 | 1054 | chip_dbg(chip, "%s: status %d\n", __func__, status); |
d8f388d8 DB |
1055 | } |
1056 | ||
1057 | return status; | |
1058 | } | |
1059 | ||
1060 | static void gpiochip_unexport(struct gpio_chip *chip) | |
1061 | { | |
1062 | int status; | |
1063 | struct device *dev; | |
1064 | ||
1065 | mutex_lock(&sysfs_lock); | |
1066 | dev = class_find_device(&gpio_class, NULL, chip, match_export); | |
1067 | if (dev) { | |
1068 | put_device(dev); | |
1069 | device_unregister(dev); | |
9fb1f39e | 1070 | chip->exported = false; |
d8f388d8 DB |
1071 | status = 0; |
1072 | } else | |
1073 | status = -ENODEV; | |
1074 | mutex_unlock(&sysfs_lock); | |
1075 | ||
1076 | if (status) | |
1a2a99c6 | 1077 | chip_dbg(chip, "%s: status %d\n", __func__, status); |
d8f388d8 DB |
1078 | } |
1079 | ||
1080 | static int __init gpiolib_sysfs_init(void) | |
1081 | { | |
1082 | int status; | |
1083 | unsigned long flags; | |
65493e3a | 1084 | struct gpio_chip *chip; |
d8f388d8 DB |
1085 | |
1086 | status = class_register(&gpio_class); | |
1087 | if (status < 0) | |
1088 | return status; | |
1089 | ||
1090 | /* Scan and register the gpio_chips which registered very | |
1091 | * early (e.g. before the class_register above was called). | |
1092 | * | |
1093 | * We run before arch_initcall() so chip->dev nodes can have | |
1094 | * registered, and so arch_initcall() can always gpio_export(). | |
1095 | */ | |
1096 | spin_lock_irqsave(&gpio_lock, flags); | |
65493e3a | 1097 | list_for_each_entry(chip, &gpio_chips, list) { |
d8f388d8 DB |
1098 | if (!chip || chip->exported) |
1099 | continue; | |
1100 | ||
1101 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1102 | status = gpiochip_export(chip); | |
1103 | spin_lock_irqsave(&gpio_lock, flags); | |
1104 | } | |
1105 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1106 | ||
1107 | ||
1108 | return status; | |
1109 | } | |
1110 | postcore_initcall(gpiolib_sysfs_init); | |
1111 | ||
1112 | #else | |
1113 | static inline int gpiochip_export(struct gpio_chip *chip) | |
1114 | { | |
1115 | return 0; | |
1116 | } | |
1117 | ||
1118 | static inline void gpiochip_unexport(struct gpio_chip *chip) | |
1119 | { | |
1120 | } | |
1121 | ||
1122 | #endif /* CONFIG_GPIO_SYSFS */ | |
1123 | ||
1a989d0f AC |
1124 | /* |
1125 | * Add a new chip to the global chips list, keeping the list of chips sorted | |
1126 | * by base order. | |
1127 | * | |
1128 | * Return -EBUSY if the new chip overlaps with some other chip's integer | |
1129 | * space. | |
1130 | */ | |
1131 | static int gpiochip_add_to_list(struct gpio_chip *chip) | |
1132 | { | |
1133 | struct list_head *pos = &gpio_chips; | |
1134 | struct gpio_chip *_chip; | |
1135 | int err = 0; | |
1136 | ||
1137 | /* find where to insert our chip */ | |
1138 | list_for_each(pos, &gpio_chips) { | |
1139 | _chip = list_entry(pos, struct gpio_chip, list); | |
1140 | /* shall we insert before _chip? */ | |
1141 | if (_chip->base >= chip->base + chip->ngpio) | |
1142 | break; | |
1143 | } | |
1144 | ||
1145 | /* are we stepping on the chip right before? */ | |
1146 | if (pos != &gpio_chips && pos->prev != &gpio_chips) { | |
1147 | _chip = list_entry(pos->prev, struct gpio_chip, list); | |
1148 | if (_chip->base + _chip->ngpio > chip->base) { | |
1149 | dev_err(chip->dev, | |
1150 | "GPIO integer space overlap, cannot add chip\n"); | |
1151 | err = -EBUSY; | |
1152 | } | |
1153 | } | |
1154 | ||
1155 | if (!err) | |
1156 | list_add_tail(&chip->list, pos); | |
1157 | ||
1158 | return err; | |
1159 | } | |
1160 | ||
d2876d08 DB |
1161 | /** |
1162 | * gpiochip_add() - register a gpio_chip | |
1163 | * @chip: the chip to register, with chip->base initialized | |
1164 | * Context: potentially before irqs or kmalloc will work | |
1165 | * | |
1166 | * Returns a negative errno if the chip can't be registered, such as | |
1167 | * because the chip->base is invalid or already associated with a | |
1168 | * different chip. Otherwise it returns zero as a success code. | |
8d0aab2f | 1169 | * |
d8f388d8 DB |
1170 | * When gpiochip_add() is called very early during boot, so that GPIOs |
1171 | * can be freely used, the chip->dev device must be registered before | |
1172 | * the gpio framework's arch_initcall(). Otherwise sysfs initialization | |
1173 | * for GPIOs will fail rudely. | |
1174 | * | |
8d0aab2f AV |
1175 | * If chip->base is negative, this requests dynamic assignment of |
1176 | * a range of valid GPIOs. | |
d2876d08 DB |
1177 | */ |
1178 | int gpiochip_add(struct gpio_chip *chip) | |
1179 | { | |
1180 | unsigned long flags; | |
1181 | int status = 0; | |
1182 | unsigned id; | |
8d0aab2f | 1183 | int base = chip->base; |
d2876d08 | 1184 | |
bff5fda9 | 1185 | if ((!gpio_is_valid(base) || !gpio_is_valid(base + chip->ngpio - 1)) |
8d0aab2f | 1186 | && base >= 0) { |
d2876d08 DB |
1187 | status = -EINVAL; |
1188 | goto fail; | |
1189 | } | |
1190 | ||
1191 | spin_lock_irqsave(&gpio_lock, flags); | |
1192 | ||
8d0aab2f AV |
1193 | if (base < 0) { |
1194 | base = gpiochip_find_base(chip->ngpio); | |
1195 | if (base < 0) { | |
1196 | status = base; | |
d8f388d8 | 1197 | goto unlock; |
8d0aab2f AV |
1198 | } |
1199 | chip->base = base; | |
1200 | } | |
1201 | ||
1a989d0f AC |
1202 | status = gpiochip_add_to_list(chip); |
1203 | ||
d2876d08 | 1204 | if (status == 0) { |
6c0b4e6c AC |
1205 | chip->desc = &gpio_desc[chip->base]; |
1206 | ||
1207 | for (id = 0; id < chip->ngpio; id++) { | |
1208 | struct gpio_desc *desc = &chip->desc[id]; | |
1209 | desc->chip = chip; | |
d8f388d8 DB |
1210 | |
1211 | /* REVISIT: most hardware initializes GPIOs as | |
1212 | * inputs (often with pullups enabled) so power | |
1213 | * usage is minimized. Linux code should set the | |
1214 | * gpio direction first thing; but until it does, | |
80b0a602 | 1215 | * and in case chip->get_direction is not set, |
d8f388d8 DB |
1216 | * we may expose the wrong direction in sysfs. |
1217 | */ | |
6c0b4e6c | 1218 | desc->flags = !chip->direction_input |
d8f388d8 DB |
1219 | ? (1 << FLAG_IS_OUT) |
1220 | : 0; | |
d2876d08 DB |
1221 | } |
1222 | } | |
1223 | ||
3bae4811 ZG |
1224 | spin_unlock_irqrestore(&gpio_lock, flags); |
1225 | ||
f23f1516 SH |
1226 | #ifdef CONFIG_PINCTRL |
1227 | INIT_LIST_HEAD(&chip->pin_ranges); | |
1228 | #endif | |
1229 | ||
391c970c | 1230 | of_gpiochip_add(chip); |
664e3e5a | 1231 | acpi_gpiochip_add(chip); |
391c970c | 1232 | |
cedb1881 AV |
1233 | if (status) |
1234 | goto fail; | |
1235 | ||
1236 | status = gpiochip_export(chip); | |
1237 | if (status) | |
1238 | goto fail; | |
1239 | ||
7589e59f | 1240 | pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__, |
64842aad GL |
1241 | chip->base, chip->base + chip->ngpio - 1, |
1242 | chip->label ? : "generic"); | |
1243 | ||
cedb1881 | 1244 | return 0; |
3bae4811 ZG |
1245 | |
1246 | unlock: | |
1247 | spin_unlock_irqrestore(&gpio_lock, flags); | |
d2876d08 DB |
1248 | fail: |
1249 | /* failures here can mean systems won't boot... */ | |
7589e59f | 1250 | pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__, |
cedb1881 AV |
1251 | chip->base, chip->base + chip->ngpio - 1, |
1252 | chip->label ? : "generic"); | |
d2876d08 DB |
1253 | return status; |
1254 | } | |
1255 | EXPORT_SYMBOL_GPL(gpiochip_add); | |
1256 | ||
14250520 LW |
1257 | /* Forward-declaration */ |
1258 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); | |
1259 | ||
d2876d08 DB |
1260 | /** |
1261 | * gpiochip_remove() - unregister a gpio_chip | |
1262 | * @chip: the chip to unregister | |
1263 | * | |
1264 | * A gpio_chip with any GPIOs still requested may not be removed. | |
1265 | */ | |
1266 | int gpiochip_remove(struct gpio_chip *chip) | |
1267 | { | |
1268 | unsigned long flags; | |
1269 | int status = 0; | |
1270 | unsigned id; | |
1271 | ||
6072b9dc MW |
1272 | acpi_gpiochip_remove(chip); |
1273 | ||
d2876d08 DB |
1274 | spin_lock_irqsave(&gpio_lock, flags); |
1275 | ||
14250520 | 1276 | gpiochip_irqchip_remove(chip); |
9ef0d6f7 | 1277 | gpiochip_remove_pin_ranges(chip); |
391c970c AV |
1278 | of_gpiochip_remove(chip); |
1279 | ||
6c0b4e6c AC |
1280 | for (id = 0; id < chip->ngpio; id++) { |
1281 | if (test_bit(FLAG_REQUESTED, &chip->desc[id].flags)) { | |
d2876d08 DB |
1282 | status = -EBUSY; |
1283 | break; | |
1284 | } | |
1285 | } | |
1286 | if (status == 0) { | |
6c0b4e6c AC |
1287 | for (id = 0; id < chip->ngpio; id++) |
1288 | chip->desc[id].chip = NULL; | |
1a989d0f AC |
1289 | |
1290 | list_del(&chip->list); | |
d2876d08 DB |
1291 | } |
1292 | ||
1293 | spin_unlock_irqrestore(&gpio_lock, flags); | |
d8f388d8 DB |
1294 | |
1295 | if (status == 0) | |
1296 | gpiochip_unexport(chip); | |
1297 | ||
d2876d08 DB |
1298 | return status; |
1299 | } | |
1300 | EXPORT_SYMBOL_GPL(gpiochip_remove); | |
1301 | ||
594fa265 GL |
1302 | /** |
1303 | * gpiochip_find() - iterator for locating a specific gpio_chip | |
1304 | * @data: data to pass to match function | |
1305 | * @callback: Callback function to check gpio_chip | |
1306 | * | |
1307 | * Similar to bus_find_device. It returns a reference to a gpio_chip as | |
1308 | * determined by a user supplied @match callback. The callback should return | |
1309 | * 0 if the device doesn't match and non-zero if it does. If the callback is | |
1310 | * non-zero, this function will return to the caller and not iterate over any | |
1311 | * more gpio_chips. | |
1312 | */ | |
07ce8ec7 | 1313 | struct gpio_chip *gpiochip_find(void *data, |
6e2cf651 | 1314 | int (*match)(struct gpio_chip *chip, |
3d0f7cf0 | 1315 | void *data)) |
594fa265 | 1316 | { |
125eef96 | 1317 | struct gpio_chip *chip; |
594fa265 | 1318 | unsigned long flags; |
594fa265 GL |
1319 | |
1320 | spin_lock_irqsave(&gpio_lock, flags); | |
125eef96 AC |
1321 | list_for_each_entry(chip, &gpio_chips, list) |
1322 | if (match(chip, data)) | |
594fa265 | 1323 | break; |
125eef96 AC |
1324 | |
1325 | /* No match? */ | |
1326 | if (&chip->list == &gpio_chips) | |
1327 | chip = NULL; | |
594fa265 GL |
1328 | spin_unlock_irqrestore(&gpio_lock, flags); |
1329 | ||
1330 | return chip; | |
1331 | } | |
8fa0c9bf | 1332 | EXPORT_SYMBOL_GPL(gpiochip_find); |
d2876d08 | 1333 | |
79697ef9 AC |
1334 | static int gpiochip_match_name(struct gpio_chip *chip, void *data) |
1335 | { | |
1336 | const char *name = data; | |
1337 | ||
1338 | return !strcmp(chip->label, name); | |
1339 | } | |
1340 | ||
1341 | static struct gpio_chip *find_chip_by_name(const char *name) | |
1342 | { | |
1343 | return gpiochip_find((void *)name, gpiochip_match_name); | |
1344 | } | |
1345 | ||
14250520 LW |
1346 | #ifdef CONFIG_GPIOLIB_IRQCHIP |
1347 | ||
1348 | /* | |
1349 | * The following is irqchip helper code for gpiochips. | |
1350 | */ | |
1351 | ||
1352 | /** | |
1353 | * gpiochip_add_chained_irqchip() - adds a chained irqchip to a gpiochip | |
1354 | * @gpiochip: the gpiochip to add the irqchip to | |
1355 | * @irqchip: the irqchip to add to the gpiochip | |
1356 | * @parent_irq: the irq number corresponding to the parent IRQ for this | |
1357 | * chained irqchip | |
1358 | * @parent_handler: the parent interrupt handler for the accumulated IRQ | |
1359 | * coming out of the gpiochip | |
1360 | */ | |
1361 | void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, | |
1362 | struct irq_chip *irqchip, | |
1363 | int parent_irq, | |
1364 | irq_flow_handler_t parent_handler) | |
1365 | { | |
1366 | irq_set_chained_handler(parent_irq, parent_handler); | |
1367 | /* | |
1368 | * The parent irqchip is already using the chip_data for this | |
1369 | * irqchip, so our callbacks simply use the handler_data. | |
1370 | */ | |
1371 | irq_set_handler_data(parent_irq, gpiochip); | |
1372 | } | |
1373 | EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip); | |
1374 | ||
1375 | /** | |
1376 | * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip | |
1377 | * @d: the irqdomain used by this irqchip | |
1378 | * @irq: the global irq number used by this GPIO irqchip irq | |
1379 | * @hwirq: the local IRQ/GPIO line offset on this gpiochip | |
1380 | * | |
1381 | * This function will set up the mapping for a certain IRQ line on a | |
1382 | * gpiochip by assigning the gpiochip as chip data, and using the irqchip | |
1383 | * stored inside the gpiochip. | |
1384 | */ | |
1385 | static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, | |
1386 | irq_hw_number_t hwirq) | |
1387 | { | |
1388 | struct gpio_chip *chip = d->host_data; | |
1389 | ||
1390 | irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler); | |
1391 | irq_set_chip_data(irq, chip); | |
1392 | #ifdef CONFIG_ARM | |
1393 | set_irq_flags(irq, IRQF_VALID); | |
1394 | #else | |
1395 | irq_set_noprobe(irq); | |
1396 | #endif | |
1397 | irq_set_irq_type(irq, chip->irq_default_type); | |
1398 | ||
1399 | return 0; | |
1400 | } | |
1401 | ||
1402 | static const struct irq_domain_ops gpiochip_domain_ops = { | |
1403 | .map = gpiochip_irq_map, | |
1404 | /* Virtually all GPIO irqchips are twocell:ed */ | |
1405 | .xlate = irq_domain_xlate_twocell, | |
1406 | }; | |
1407 | ||
1408 | static int gpiochip_irq_reqres(struct irq_data *d) | |
1409 | { | |
1410 | struct gpio_chip *chip = irq_data_get_irq_chip_data(d); | |
1411 | ||
1412 | if (gpio_lock_as_irq(chip, d->hwirq)) { | |
1413 | chip_err(chip, | |
1414 | "unable to lock HW IRQ %lu for IRQ\n", | |
1415 | d->hwirq); | |
1416 | return -EINVAL; | |
1417 | } | |
1418 | return 0; | |
1419 | } | |
1420 | ||
1421 | static void gpiochip_irq_relres(struct irq_data *d) | |
1422 | { | |
1423 | struct gpio_chip *chip = irq_data_get_irq_chip_data(d); | |
1424 | ||
1425 | gpio_unlock_as_irq(chip, d->hwirq); | |
1426 | } | |
1427 | ||
1428 | static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) | |
1429 | { | |
1430 | return irq_find_mapping(chip->irqdomain, offset); | |
1431 | } | |
1432 | ||
1433 | /** | |
1434 | * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip | |
1435 | * @gpiochip: the gpiochip to remove the irqchip from | |
1436 | * | |
1437 | * This is called only from gpiochip_remove() | |
1438 | */ | |
1439 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) | |
1440 | { | |
1441 | if (gpiochip->irqdomain) | |
1442 | irq_domain_remove(gpiochip->irqdomain); | |
1443 | ||
1444 | if (gpiochip->irqchip) { | |
1445 | gpiochip->irqchip->irq_request_resources = NULL; | |
1446 | gpiochip->irqchip->irq_release_resources = NULL; | |
1447 | gpiochip->irqchip = NULL; | |
1448 | } | |
1449 | } | |
1450 | ||
1451 | /** | |
1452 | * gpiochip_irqchip_add() - adds an irqchip to a gpiochip | |
1453 | * @gpiochip: the gpiochip to add the irqchip to | |
1454 | * @irqchip: the irqchip to add to the gpiochip | |
1455 | * @first_irq: if not dynamically assigned, the base (first) IRQ to | |
1456 | * allocate gpiochip irqs from | |
1457 | * @handler: the irq handler to use (often a predefined irq core function) | |
1458 | * @type: the default type for IRQs on this irqchip | |
1459 | * | |
1460 | * This function closely associates a certain irqchip with a certain | |
1461 | * gpiochip, providing an irq domain to translate the local IRQs to | |
1462 | * global irqs in the gpiolib core, and making sure that the gpiochip | |
1463 | * is passed as chip data to all related functions. Driver callbacks | |
1464 | * need to use container_of() to get their local state containers back | |
1465 | * from the gpiochip passed as chip data. An irqdomain will be stored | |
1466 | * in the gpiochip that shall be used by the driver to handle IRQ number | |
1467 | * translation. The gpiochip will need to be initialized and registered | |
1468 | * before calling this function. | |
1469 | * | |
1470 | * This function will handle two cell:ed simple IRQs. Everything else | |
1471 | * need to be open coded. | |
1472 | */ | |
1473 | int gpiochip_irqchip_add(struct gpio_chip *gpiochip, | |
1474 | struct irq_chip *irqchip, | |
1475 | unsigned int first_irq, | |
1476 | irq_flow_handler_t handler, | |
1477 | unsigned int type) | |
1478 | { | |
1479 | struct device_node *of_node; | |
1480 | unsigned int offset; | |
1481 | ||
1482 | if (!gpiochip || !irqchip) | |
1483 | return -EINVAL; | |
1484 | ||
1485 | if (!gpiochip->dev) { | |
1486 | pr_err("missing gpiochip .dev parent pointer\n"); | |
1487 | return -EINVAL; | |
1488 | } | |
1489 | of_node = gpiochip->dev->of_node; | |
1490 | #ifdef CONFIG_OF_GPIO | |
1491 | /* | |
1492 | * If the gpiochip has an assigned OF node this takes precendence | |
1493 | * FIXME: get rid of this and use gpiochip->dev->of_node everywhere | |
1494 | */ | |
1495 | if (gpiochip->of_node) | |
1496 | of_node = gpiochip->of_node; | |
1497 | #endif | |
1498 | gpiochip->irqchip = irqchip; | |
1499 | gpiochip->irq_handler = handler; | |
1500 | gpiochip->irq_default_type = type; | |
1501 | gpiochip->to_irq = gpiochip_to_irq; | |
1502 | gpiochip->irqdomain = irq_domain_add_simple(of_node, | |
1503 | gpiochip->ngpio, first_irq, | |
1504 | &gpiochip_domain_ops, gpiochip); | |
1505 | if (!gpiochip->irqdomain) { | |
1506 | gpiochip->irqchip = NULL; | |
1507 | return -EINVAL; | |
1508 | } | |
1509 | irqchip->irq_request_resources = gpiochip_irq_reqres; | |
1510 | irqchip->irq_release_resources = gpiochip_irq_relres; | |
1511 | ||
1512 | /* | |
1513 | * Prepare the mapping since the irqchip shall be orthogonal to | |
1514 | * any gpiochip calls. If the first_irq was zero, this is | |
1515 | * necessary to allocate descriptors for all IRQs. | |
1516 | */ | |
1517 | for (offset = 0; offset < gpiochip->ngpio; offset++) | |
1518 | irq_create_mapping(gpiochip->irqdomain, offset); | |
1519 | ||
1520 | return 0; | |
1521 | } | |
1522 | EXPORT_SYMBOL_GPL(gpiochip_irqchip_add); | |
1523 | ||
1524 | #else /* CONFIG_GPIOLIB_IRQCHIP */ | |
1525 | ||
1526 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {} | |
1527 | ||
1528 | #endif /* CONFIG_GPIOLIB_IRQCHIP */ | |
1529 | ||
f23f1516 | 1530 | #ifdef CONFIG_PINCTRL |
165adc9c | 1531 | |
586a87e6 CR |
1532 | /** |
1533 | * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping | |
1534 | * @chip: the gpiochip to add the range for | |
1535 | * @pinctrl: the dev_name() of the pin controller to map to | |
1536 | * @gpio_offset: the start offset in the current gpio_chip number space | |
1537 | * @pin_group: name of the pin group inside the pin controller | |
1538 | */ | |
1539 | int gpiochip_add_pingroup_range(struct gpio_chip *chip, | |
1540 | struct pinctrl_dev *pctldev, | |
1541 | unsigned int gpio_offset, const char *pin_group) | |
1542 | { | |
1543 | struct gpio_pin_range *pin_range; | |
1544 | int ret; | |
1545 | ||
1546 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); | |
1547 | if (!pin_range) { | |
1a2a99c6 | 1548 | chip_err(chip, "failed to allocate pin ranges\n"); |
586a87e6 CR |
1549 | return -ENOMEM; |
1550 | } | |
1551 | ||
1552 | /* Use local offset as range ID */ | |
1553 | pin_range->range.id = gpio_offset; | |
1554 | pin_range->range.gc = chip; | |
1555 | pin_range->range.name = chip->label; | |
1556 | pin_range->range.base = chip->base + gpio_offset; | |
1557 | pin_range->pctldev = pctldev; | |
1558 | ||
1559 | ret = pinctrl_get_group_pins(pctldev, pin_group, | |
1560 | &pin_range->range.pins, | |
1561 | &pin_range->range.npins); | |
61c6375d MN |
1562 | if (ret < 0) { |
1563 | kfree(pin_range); | |
586a87e6 | 1564 | return ret; |
61c6375d | 1565 | } |
586a87e6 CR |
1566 | |
1567 | pinctrl_add_gpio_range(pctldev, &pin_range->range); | |
1568 | ||
1a2a99c6 AS |
1569 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n", |
1570 | gpio_offset, gpio_offset + pin_range->range.npins - 1, | |
586a87e6 CR |
1571 | pinctrl_dev_get_devname(pctldev), pin_group); |
1572 | ||
1573 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
1574 | ||
1575 | return 0; | |
1576 | } | |
1577 | EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); | |
1578 | ||
3f0f8670 LW |
1579 | /** |
1580 | * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping | |
1581 | * @chip: the gpiochip to add the range for | |
1582 | * @pinctrl_name: the dev_name() of the pin controller to map to | |
316511c0 LW |
1583 | * @gpio_offset: the start offset in the current gpio_chip number space |
1584 | * @pin_offset: the start offset in the pin controller number space | |
3f0f8670 LW |
1585 | * @npins: the number of pins from the offset of each pin space (GPIO and |
1586 | * pin controller) to accumulate in this range | |
1587 | */ | |
1e63d7b9 | 1588 | int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, |
316511c0 | 1589 | unsigned int gpio_offset, unsigned int pin_offset, |
3f0f8670 | 1590 | unsigned int npins) |
f23f1516 SH |
1591 | { |
1592 | struct gpio_pin_range *pin_range; | |
b4d4b1f0 | 1593 | int ret; |
f23f1516 | 1594 | |
3f0f8670 | 1595 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); |
f23f1516 | 1596 | if (!pin_range) { |
1a2a99c6 | 1597 | chip_err(chip, "failed to allocate pin ranges\n"); |
1e63d7b9 | 1598 | return -ENOMEM; |
f23f1516 SH |
1599 | } |
1600 | ||
3f0f8670 | 1601 | /* Use local offset as range ID */ |
316511c0 | 1602 | pin_range->range.id = gpio_offset; |
3f0f8670 | 1603 | pin_range->range.gc = chip; |
f23f1516 | 1604 | pin_range->range.name = chip->label; |
316511c0 LW |
1605 | pin_range->range.base = chip->base + gpio_offset; |
1606 | pin_range->range.pin_base = pin_offset; | |
f23f1516 | 1607 | pin_range->range.npins = npins; |
192c369c | 1608 | pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, |
f23f1516 | 1609 | &pin_range->range); |
8f23ca1a | 1610 | if (IS_ERR(pin_range->pctldev)) { |
b4d4b1f0 | 1611 | ret = PTR_ERR(pin_range->pctldev); |
1a2a99c6 | 1612 | chip_err(chip, "could not create pin range\n"); |
3f0f8670 | 1613 | kfree(pin_range); |
b4d4b1f0 | 1614 | return ret; |
3f0f8670 | 1615 | } |
1a2a99c6 AS |
1616 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n", |
1617 | gpio_offset, gpio_offset + npins - 1, | |
316511c0 LW |
1618 | pinctl_name, |
1619 | pin_offset, pin_offset + npins - 1); | |
f23f1516 SH |
1620 | |
1621 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
1e63d7b9 LW |
1622 | |
1623 | return 0; | |
f23f1516 | 1624 | } |
165adc9c | 1625 | EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); |
f23f1516 | 1626 | |
3f0f8670 LW |
1627 | /** |
1628 | * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings | |
1629 | * @chip: the chip to remove all the mappings for | |
1630 | */ | |
f23f1516 SH |
1631 | void gpiochip_remove_pin_ranges(struct gpio_chip *chip) |
1632 | { | |
1633 | struct gpio_pin_range *pin_range, *tmp; | |
1634 | ||
1635 | list_for_each_entry_safe(pin_range, tmp, &chip->pin_ranges, node) { | |
1636 | list_del(&pin_range->node); | |
1637 | pinctrl_remove_gpio_range(pin_range->pctldev, | |
1638 | &pin_range->range); | |
3f0f8670 | 1639 | kfree(pin_range); |
f23f1516 SH |
1640 | } |
1641 | } | |
165adc9c LW |
1642 | EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); |
1643 | ||
1644 | #endif /* CONFIG_PINCTRL */ | |
f23f1516 | 1645 | |
d2876d08 DB |
1646 | /* These "optional" allocation calls help prevent drivers from stomping |
1647 | * on each other, and help provide better diagnostics in debugfs. | |
1648 | * They're called even less than the "set direction" calls. | |
1649 | */ | |
77c2d792 | 1650 | static int __gpiod_request(struct gpio_desc *desc, const char *label) |
d2876d08 | 1651 | { |
77c2d792 MW |
1652 | struct gpio_chip *chip = desc->chip; |
1653 | int status; | |
d2876d08 DB |
1654 | unsigned long flags; |
1655 | ||
bcabdef1 AC |
1656 | spin_lock_irqsave(&gpio_lock, flags); |
1657 | ||
d2876d08 | 1658 | /* NOTE: gpio_request() can be called in early boot, |
35e8bb51 | 1659 | * before IRQs are enabled, for non-sleeping (SOC) GPIOs. |
d2876d08 DB |
1660 | */ |
1661 | ||
1662 | if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { | |
1663 | desc_set_label(desc, label ? : "?"); | |
1664 | status = 0; | |
438d8908 | 1665 | } else { |
d2876d08 | 1666 | status = -EBUSY; |
7460db56 | 1667 | goto done; |
35e8bb51 DB |
1668 | } |
1669 | ||
1670 | if (chip->request) { | |
1671 | /* chip->request may sleep */ | |
1672 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 1673 | status = chip->request(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
1674 | spin_lock_irqsave(&gpio_lock, flags); |
1675 | ||
1676 | if (status < 0) { | |
1677 | desc_set_label(desc, NULL); | |
35e8bb51 | 1678 | clear_bit(FLAG_REQUESTED, &desc->flags); |
80b0a602 | 1679 | goto done; |
35e8bb51 | 1680 | } |
438d8908 | 1681 | } |
80b0a602 MN |
1682 | if (chip->get_direction) { |
1683 | /* chip->get_direction may sleep */ | |
1684 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 1685 | gpiod_get_direction(desc); |
80b0a602 MN |
1686 | spin_lock_irqsave(&gpio_lock, flags); |
1687 | } | |
77c2d792 MW |
1688 | done: |
1689 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1690 | return status; | |
1691 | } | |
1692 | ||
1693 | static int gpiod_request(struct gpio_desc *desc, const char *label) | |
1694 | { | |
1695 | int status = -EPROBE_DEFER; | |
1696 | struct gpio_chip *chip; | |
1697 | ||
1698 | if (!desc) { | |
1699 | pr_warn("%s: invalid GPIO\n", __func__); | |
1700 | return -EINVAL; | |
1701 | } | |
1702 | ||
1703 | chip = desc->chip; | |
1704 | if (!chip) | |
1705 | goto done; | |
1706 | ||
1707 | if (try_module_get(chip->owner)) { | |
1708 | status = __gpiod_request(desc, label); | |
1709 | if (status < 0) | |
1710 | module_put(chip->owner); | |
1711 | } | |
1712 | ||
d2876d08 DB |
1713 | done: |
1714 | if (status) | |
7589e59f | 1715 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
77c2d792 | 1716 | |
d2876d08 DB |
1717 | return status; |
1718 | } | |
372e722e AC |
1719 | |
1720 | int gpio_request(unsigned gpio, const char *label) | |
1721 | { | |
1722 | return gpiod_request(gpio_to_desc(gpio), label); | |
1723 | } | |
d2876d08 DB |
1724 | EXPORT_SYMBOL_GPL(gpio_request); |
1725 | ||
77c2d792 | 1726 | static bool __gpiod_free(struct gpio_desc *desc) |
d2876d08 | 1727 | { |
77c2d792 | 1728 | bool ret = false; |
d2876d08 | 1729 | unsigned long flags; |
35e8bb51 | 1730 | struct gpio_chip *chip; |
d2876d08 | 1731 | |
3d599d1c UKK |
1732 | might_sleep(); |
1733 | ||
372e722e | 1734 | gpiod_unexport(desc); |
d8f388d8 | 1735 | |
d2876d08 DB |
1736 | spin_lock_irqsave(&gpio_lock, flags); |
1737 | ||
35e8bb51 DB |
1738 | chip = desc->chip; |
1739 | if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { | |
1740 | if (chip->free) { | |
1741 | spin_unlock_irqrestore(&gpio_lock, flags); | |
9c4ba946 | 1742 | might_sleep_if(chip->can_sleep); |
372e722e | 1743 | chip->free(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
1744 | spin_lock_irqsave(&gpio_lock, flags); |
1745 | } | |
d2876d08 | 1746 | desc_set_label(desc, NULL); |
07697461 | 1747 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); |
35e8bb51 | 1748 | clear_bit(FLAG_REQUESTED, &desc->flags); |
aca5ce14 | 1749 | clear_bit(FLAG_OPEN_DRAIN, &desc->flags); |
25553ff0 | 1750 | clear_bit(FLAG_OPEN_SOURCE, &desc->flags); |
77c2d792 MW |
1751 | ret = true; |
1752 | } | |
d2876d08 DB |
1753 | |
1754 | spin_unlock_irqrestore(&gpio_lock, flags); | |
77c2d792 MW |
1755 | return ret; |
1756 | } | |
1757 | ||
1758 | static void gpiod_free(struct gpio_desc *desc) | |
1759 | { | |
1760 | if (desc && __gpiod_free(desc)) | |
1761 | module_put(desc->chip->owner); | |
1762 | else | |
1763 | WARN_ON(extra_checks); | |
d2876d08 | 1764 | } |
372e722e AC |
1765 | |
1766 | void gpio_free(unsigned gpio) | |
1767 | { | |
1768 | gpiod_free(gpio_to_desc(gpio)); | |
1769 | } | |
d2876d08 DB |
1770 | EXPORT_SYMBOL_GPL(gpio_free); |
1771 | ||
3e45f1d1 EM |
1772 | /** |
1773 | * gpio_request_one - request a single GPIO with initial configuration | |
1774 | * @gpio: the GPIO number | |
1775 | * @flags: GPIO configuration as specified by GPIOF_* | |
1776 | * @label: a literal description string of this GPIO | |
1777 | */ | |
1778 | int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) | |
1779 | { | |
372e722e | 1780 | struct gpio_desc *desc; |
3e45f1d1 EM |
1781 | int err; |
1782 | ||
372e722e AC |
1783 | desc = gpio_to_desc(gpio); |
1784 | ||
1785 | err = gpiod_request(desc, label); | |
3e45f1d1 EM |
1786 | if (err) |
1787 | return err; | |
1788 | ||
aca5ce14 | 1789 | if (flags & GPIOF_OPEN_DRAIN) |
372e722e | 1790 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); |
aca5ce14 | 1791 | |
25553ff0 | 1792 | if (flags & GPIOF_OPEN_SOURCE) |
372e722e | 1793 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); |
25553ff0 | 1794 | |
3e45f1d1 | 1795 | if (flags & GPIOF_DIR_IN) |
372e722e | 1796 | err = gpiod_direction_input(desc); |
3e45f1d1 | 1797 | else |
ef70bbe1 | 1798 | err = gpiod_direction_output_raw(desc, |
3e45f1d1 EM |
1799 | (flags & GPIOF_INIT_HIGH) ? 1 : 0); |
1800 | ||
e254811c | 1801 | if (err) |
fc3a1f04 WS |
1802 | goto free_gpio; |
1803 | ||
1804 | if (flags & GPIOF_EXPORT) { | |
372e722e | 1805 | err = gpiod_export(desc, flags & GPIOF_EXPORT_CHANGEABLE); |
fc3a1f04 WS |
1806 | if (err) |
1807 | goto free_gpio; | |
1808 | } | |
1809 | ||
1810 | return 0; | |
e254811c | 1811 | |
fc3a1f04 | 1812 | free_gpio: |
372e722e | 1813 | gpiod_free(desc); |
3e45f1d1 EM |
1814 | return err; |
1815 | } | |
1816 | EXPORT_SYMBOL_GPL(gpio_request_one); | |
1817 | ||
1818 | /** | |
1819 | * gpio_request_array - request multiple GPIOs in a single call | |
1820 | * @array: array of the 'struct gpio' | |
1821 | * @num: how many GPIOs in the array | |
1822 | */ | |
7c295975 | 1823 | int gpio_request_array(const struct gpio *array, size_t num) |
3e45f1d1 EM |
1824 | { |
1825 | int i, err; | |
1826 | ||
1827 | for (i = 0; i < num; i++, array++) { | |
1828 | err = gpio_request_one(array->gpio, array->flags, array->label); | |
1829 | if (err) | |
1830 | goto err_free; | |
1831 | } | |
1832 | return 0; | |
1833 | ||
1834 | err_free: | |
1835 | while (i--) | |
1836 | gpio_free((--array)->gpio); | |
1837 | return err; | |
1838 | } | |
1839 | EXPORT_SYMBOL_GPL(gpio_request_array); | |
1840 | ||
1841 | /** | |
1842 | * gpio_free_array - release multiple GPIOs in a single call | |
1843 | * @array: array of the 'struct gpio' | |
1844 | * @num: how many GPIOs in the array | |
1845 | */ | |
7c295975 | 1846 | void gpio_free_array(const struct gpio *array, size_t num) |
3e45f1d1 EM |
1847 | { |
1848 | while (num--) | |
1849 | gpio_free((array++)->gpio); | |
1850 | } | |
1851 | EXPORT_SYMBOL_GPL(gpio_free_array); | |
d2876d08 DB |
1852 | |
1853 | /** | |
1854 | * gpiochip_is_requested - return string iff signal was requested | |
1855 | * @chip: controller managing the signal | |
1856 | * @offset: of signal within controller's 0..(ngpio - 1) range | |
1857 | * | |
1858 | * Returns NULL if the GPIO is not currently requested, else a string. | |
1859 | * If debugfs support is enabled, the string returned is the label passed | |
1860 | * to gpio_request(); otherwise it is a meaningless constant. | |
1861 | * | |
1862 | * This function is for use by GPIO controller drivers. The label can | |
1863 | * help with diagnostics, and knowing that the signal is used as a GPIO | |
1864 | * can help avoid accidentally multiplexing it to another controller. | |
1865 | */ | |
1866 | const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) | |
1867 | { | |
6c0b4e6c | 1868 | struct gpio_desc *desc; |
d2876d08 | 1869 | |
6c0b4e6c | 1870 | if (!GPIO_OFFSET_VALID(chip, offset)) |
d2876d08 | 1871 | return NULL; |
6c0b4e6c AC |
1872 | |
1873 | desc = &chip->desc[offset]; | |
1874 | ||
372e722e | 1875 | if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) |
d2876d08 DB |
1876 | return NULL; |
1877 | #ifdef CONFIG_DEBUG_FS | |
372e722e | 1878 | return desc->label; |
d2876d08 DB |
1879 | #else |
1880 | return "?"; | |
1881 | #endif | |
1882 | } | |
1883 | EXPORT_SYMBOL_GPL(gpiochip_is_requested); | |
1884 | ||
77c2d792 MW |
1885 | /** |
1886 | * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor | |
1887 | * @desc: GPIO descriptor to request | |
1888 | * @label: label for the GPIO | |
1889 | * | |
1890 | * Function allows GPIO chip drivers to request and use their own GPIO | |
1891 | * descriptors via gpiolib API. Difference to gpiod_request() is that this | |
1892 | * function will not increase reference count of the GPIO chip module. This | |
1893 | * allows the GPIO chip module to be unloaded as needed (we assume that the | |
1894 | * GPIO chip driver handles freeing the GPIOs it has requested). | |
1895 | */ | |
1896 | int gpiochip_request_own_desc(struct gpio_desc *desc, const char *label) | |
1897 | { | |
1898 | if (!desc || !desc->chip) | |
1899 | return -EINVAL; | |
1900 | ||
1901 | return __gpiod_request(desc, label); | |
1902 | } | |
1903 | ||
1904 | /** | |
1905 | * gpiochip_free_own_desc - Free GPIO requested by the chip driver | |
1906 | * @desc: GPIO descriptor to free | |
1907 | * | |
1908 | * Function frees the given GPIO requested previously with | |
1909 | * gpiochip_request_own_desc(). | |
1910 | */ | |
1911 | void gpiochip_free_own_desc(struct gpio_desc *desc) | |
1912 | { | |
1913 | if (desc) | |
1914 | __gpiod_free(desc); | |
1915 | } | |
d2876d08 DB |
1916 | |
1917 | /* Drivers MUST set GPIO direction before making get/set calls. In | |
1918 | * some cases this is done in early boot, before IRQs are enabled. | |
1919 | * | |
1920 | * As a rule these aren't called more than once (except for drivers | |
1921 | * using the open-drain emulation idiom) so these are natural places | |
1922 | * to accumulate extra debugging checks. Note that we can't (yet) | |
1923 | * rely on gpio_request() having been called beforehand. | |
1924 | */ | |
1925 | ||
79a9becd AC |
1926 | /** |
1927 | * gpiod_direction_input - set the GPIO direction to input | |
1928 | * @desc: GPIO to set to input | |
1929 | * | |
1930 | * Set the direction of the passed GPIO to input, such as gpiod_get_value() can | |
1931 | * be called safely on it. | |
1932 | * | |
1933 | * Return 0 in case of success, else an error code. | |
1934 | */ | |
1935 | int gpiod_direction_input(struct gpio_desc *desc) | |
d2876d08 DB |
1936 | { |
1937 | unsigned long flags; | |
1938 | struct gpio_chip *chip; | |
d2876d08 | 1939 | int status = -EINVAL; |
372e722e | 1940 | int offset; |
d2876d08 | 1941 | |
be1a4b13 | 1942 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1943 | pr_warn("%s: invalid GPIO\n", __func__); |
1944 | return -EINVAL; | |
1945 | } | |
1946 | ||
be1a4b13 LW |
1947 | chip = desc->chip; |
1948 | if (!chip->get || !chip->direction_input) { | |
6424de5a MB |
1949 | gpiod_warn(desc, |
1950 | "%s: missing get() or direction_input() operations\n", | |
7589e59f | 1951 | __func__); |
be1a4b13 LW |
1952 | return -EIO; |
1953 | } | |
1954 | ||
d2876d08 DB |
1955 | spin_lock_irqsave(&gpio_lock, flags); |
1956 | ||
372e722e | 1957 | status = gpio_ensure_requested(desc); |
35e8bb51 DB |
1958 | if (status < 0) |
1959 | goto fail; | |
d2876d08 DB |
1960 | |
1961 | /* now we know the gpio is valid and chip won't vanish */ | |
1962 | ||
1963 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1964 | ||
9c4ba946 | 1965 | might_sleep_if(chip->can_sleep); |
d2876d08 | 1966 | |
372e722e | 1967 | offset = gpio_chip_hwgpio(desc); |
35e8bb51 | 1968 | if (status) { |
372e722e | 1969 | status = chip->request(chip, offset); |
35e8bb51 | 1970 | if (status < 0) { |
7589e59f AS |
1971 | gpiod_dbg(desc, "%s: chip request fail, %d\n", |
1972 | __func__, status); | |
35e8bb51 DB |
1973 | /* and it's not available to anyone else ... |
1974 | * gpio_request() is the fully clean solution. | |
1975 | */ | |
1976 | goto lose; | |
1977 | } | |
1978 | } | |
1979 | ||
372e722e | 1980 | status = chip->direction_input(chip, offset); |
d2876d08 DB |
1981 | if (status == 0) |
1982 | clear_bit(FLAG_IS_OUT, &desc->flags); | |
3f397c21 | 1983 | |
372e722e | 1984 | trace_gpio_direction(desc_to_gpio(desc), 1, status); |
35e8bb51 | 1985 | lose: |
d2876d08 DB |
1986 | return status; |
1987 | fail: | |
1988 | spin_unlock_irqrestore(&gpio_lock, flags); | |
bcabdef1 | 1989 | if (status) |
7589e59f | 1990 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
d2876d08 DB |
1991 | return status; |
1992 | } | |
79a9becd | 1993 | EXPORT_SYMBOL_GPL(gpiod_direction_input); |
372e722e | 1994 | |
ef70bbe1 | 1995 | static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) |
d2876d08 DB |
1996 | { |
1997 | unsigned long flags; | |
1998 | struct gpio_chip *chip; | |
d2876d08 | 1999 | int status = -EINVAL; |
372e722e | 2000 | int offset; |
d2876d08 | 2001 | |
d468bf9e LW |
2002 | /* GPIOs used for IRQs shall not be set as output */ |
2003 | if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) { | |
2004 | gpiod_err(desc, | |
2005 | "%s: tried to set a GPIO tied to an IRQ as output\n", | |
2006 | __func__); | |
2007 | return -EIO; | |
2008 | } | |
2009 | ||
aca5ce14 LD |
2010 | /* Open drain pin should not be driven to 1 */ |
2011 | if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
372e722e | 2012 | return gpiod_direction_input(desc); |
aca5ce14 | 2013 | |
25553ff0 LD |
2014 | /* Open source pin should not be driven to 0 */ |
2015 | if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
372e722e | 2016 | return gpiod_direction_input(desc); |
25553ff0 | 2017 | |
be1a4b13 LW |
2018 | chip = desc->chip; |
2019 | if (!chip->set || !chip->direction_output) { | |
6424de5a MB |
2020 | gpiod_warn(desc, |
2021 | "%s: missing set() or direction_output() operations\n", | |
2022 | __func__); | |
be1a4b13 LW |
2023 | return -EIO; |
2024 | } | |
2025 | ||
d2876d08 DB |
2026 | spin_lock_irqsave(&gpio_lock, flags); |
2027 | ||
372e722e | 2028 | status = gpio_ensure_requested(desc); |
35e8bb51 DB |
2029 | if (status < 0) |
2030 | goto fail; | |
d2876d08 DB |
2031 | |
2032 | /* now we know the gpio is valid and chip won't vanish */ | |
2033 | ||
2034 | spin_unlock_irqrestore(&gpio_lock, flags); | |
2035 | ||
9c4ba946 | 2036 | might_sleep_if(chip->can_sleep); |
d2876d08 | 2037 | |
372e722e | 2038 | offset = gpio_chip_hwgpio(desc); |
35e8bb51 | 2039 | if (status) { |
372e722e | 2040 | status = chip->request(chip, offset); |
35e8bb51 | 2041 | if (status < 0) { |
7589e59f AS |
2042 | gpiod_dbg(desc, "%s: chip request fail, %d\n", |
2043 | __func__, status); | |
35e8bb51 DB |
2044 | /* and it's not available to anyone else ... |
2045 | * gpio_request() is the fully clean solution. | |
2046 | */ | |
2047 | goto lose; | |
2048 | } | |
2049 | } | |
2050 | ||
372e722e | 2051 | status = chip->direction_output(chip, offset, value); |
d2876d08 DB |
2052 | if (status == 0) |
2053 | set_bit(FLAG_IS_OUT, &desc->flags); | |
372e722e AC |
2054 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
2055 | trace_gpio_direction(desc_to_gpio(desc), 0, status); | |
35e8bb51 | 2056 | lose: |
d2876d08 DB |
2057 | return status; |
2058 | fail: | |
2059 | spin_unlock_irqrestore(&gpio_lock, flags); | |
bcabdef1 | 2060 | if (status) |
6424de5a | 2061 | gpiod_dbg(desc, "%s: gpio status %d\n", __func__, status); |
d2876d08 DB |
2062 | return status; |
2063 | } | |
ef70bbe1 PZ |
2064 | |
2065 | /** | |
2066 | * gpiod_direction_output_raw - set the GPIO direction to output | |
2067 | * @desc: GPIO to set to output | |
2068 | * @value: initial output value of the GPIO | |
2069 | * | |
2070 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
2071 | * be called safely on it. The initial value of the output must be specified | |
2072 | * as raw value on the physical line without regard for the ACTIVE_LOW status. | |
2073 | * | |
2074 | * Return 0 in case of success, else an error code. | |
2075 | */ | |
2076 | int gpiod_direction_output_raw(struct gpio_desc *desc, int value) | |
2077 | { | |
2078 | if (!desc || !desc->chip) { | |
2079 | pr_warn("%s: invalid GPIO\n", __func__); | |
2080 | return -EINVAL; | |
2081 | } | |
2082 | return _gpiod_direction_output_raw(desc, value); | |
2083 | } | |
2084 | EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); | |
2085 | ||
2086 | /** | |
90df4fe0 | 2087 | * gpiod_direction_output - set the GPIO direction to output |
ef70bbe1 PZ |
2088 | * @desc: GPIO to set to output |
2089 | * @value: initial output value of the GPIO | |
2090 | * | |
2091 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
2092 | * be called safely on it. The initial value of the output must be specified | |
2093 | * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
2094 | * account. | |
2095 | * | |
2096 | * Return 0 in case of success, else an error code. | |
2097 | */ | |
2098 | int gpiod_direction_output(struct gpio_desc *desc, int value) | |
2099 | { | |
2100 | if (!desc || !desc->chip) { | |
2101 | pr_warn("%s: invalid GPIO\n", __func__); | |
2102 | return -EINVAL; | |
2103 | } | |
2104 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2105 | value = !value; | |
2106 | return _gpiod_direction_output_raw(desc, value); | |
2107 | } | |
79a9becd | 2108 | EXPORT_SYMBOL_GPL(gpiod_direction_output); |
d2876d08 | 2109 | |
c4b5be98 | 2110 | /** |
79a9becd | 2111 | * gpiod_set_debounce - sets @debounce time for a @gpio |
c4b5be98 FB |
2112 | * @gpio: the gpio to set debounce time |
2113 | * @debounce: debounce time is microseconds | |
65d87656 LW |
2114 | * |
2115 | * returns -ENOTSUPP if the controller does not support setting | |
2116 | * debounce. | |
c4b5be98 | 2117 | */ |
79a9becd | 2118 | int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) |
c4b5be98 FB |
2119 | { |
2120 | unsigned long flags; | |
2121 | struct gpio_chip *chip; | |
c4b5be98 | 2122 | int status = -EINVAL; |
372e722e | 2123 | int offset; |
c4b5be98 | 2124 | |
be1a4b13 | 2125 | if (!desc || !desc->chip) { |
bcabdef1 AC |
2126 | pr_warn("%s: invalid GPIO\n", __func__); |
2127 | return -EINVAL; | |
2128 | } | |
2129 | ||
c4b5be98 | 2130 | chip = desc->chip; |
be1a4b13 | 2131 | if (!chip->set || !chip->set_debounce) { |
6424de5a MB |
2132 | gpiod_dbg(desc, |
2133 | "%s: missing set() or set_debounce() operations\n", | |
2134 | __func__); | |
65d87656 | 2135 | return -ENOTSUPP; |
be1a4b13 LW |
2136 | } |
2137 | ||
2138 | spin_lock_irqsave(&gpio_lock, flags); | |
372e722e AC |
2139 | |
2140 | status = gpio_ensure_requested(desc); | |
c4b5be98 FB |
2141 | if (status < 0) |
2142 | goto fail; | |
2143 | ||
2144 | /* now we know the gpio is valid and chip won't vanish */ | |
2145 | ||
2146 | spin_unlock_irqrestore(&gpio_lock, flags); | |
2147 | ||
9c4ba946 | 2148 | might_sleep_if(chip->can_sleep); |
c4b5be98 | 2149 | |
372e722e AC |
2150 | offset = gpio_chip_hwgpio(desc); |
2151 | return chip->set_debounce(chip, offset, debounce); | |
c4b5be98 FB |
2152 | |
2153 | fail: | |
2154 | spin_unlock_irqrestore(&gpio_lock, flags); | |
bcabdef1 | 2155 | if (status) |
6424de5a | 2156 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
c4b5be98 FB |
2157 | |
2158 | return status; | |
2159 | } | |
79a9becd | 2160 | EXPORT_SYMBOL_GPL(gpiod_set_debounce); |
372e722e | 2161 | |
79a9becd AC |
2162 | /** |
2163 | * gpiod_is_active_low - test whether a GPIO is active-low or not | |
2164 | * @desc: the gpio descriptor to test | |
2165 | * | |
2166 | * Returns 1 if the GPIO is active-low, 0 otherwise. | |
2167 | */ | |
2168 | int gpiod_is_active_low(const struct gpio_desc *desc) | |
372e722e | 2169 | { |
79a9becd | 2170 | return test_bit(FLAG_ACTIVE_LOW, &desc->flags); |
372e722e | 2171 | } |
79a9becd | 2172 | EXPORT_SYMBOL_GPL(gpiod_is_active_low); |
d2876d08 DB |
2173 | |
2174 | /* I/O calls are only valid after configuration completed; the relevant | |
2175 | * "is this a valid GPIO" error checks should already have been done. | |
2176 | * | |
2177 | * "Get" operations are often inlinable as reading a pin value register, | |
2178 | * and masking the relevant bit in that register. | |
2179 | * | |
2180 | * When "set" operations are inlinable, they involve writing that mask to | |
2181 | * one register to set a low value, or a different register to set it high. | |
2182 | * Otherwise locking is needed, so there may be little value to inlining. | |
2183 | * | |
2184 | *------------------------------------------------------------------------ | |
2185 | * | |
2186 | * IMPORTANT!!! The hot paths -- get/set value -- assume that callers | |
2187 | * have requested the GPIO. That can include implicit requesting by | |
2188 | * a direction setting call. Marking a gpio as requested locks its chip | |
2189 | * in memory, guaranteeing that these table lookups need no more locking | |
2190 | * and that gpiochip_remove() will fail. | |
2191 | * | |
2192 | * REVISIT when debugging, consider adding some instrumentation to ensure | |
2193 | * that the GPIO was actually requested. | |
2194 | */ | |
2195 | ||
23600969 | 2196 | static bool _gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 DB |
2197 | { |
2198 | struct gpio_chip *chip; | |
23600969 | 2199 | bool value; |
372e722e | 2200 | int offset; |
d2876d08 | 2201 | |
372e722e AC |
2202 | chip = desc->chip; |
2203 | offset = gpio_chip_hwgpio(desc); | |
23600969 | 2204 | value = chip->get ? chip->get(chip, offset) : false; |
372e722e | 2205 | trace_gpio_value(desc_to_gpio(desc), 1, value); |
3f397c21 | 2206 | return value; |
d2876d08 | 2207 | } |
372e722e | 2208 | |
d2876d08 | 2209 | /** |
79a9becd AC |
2210 | * gpiod_get_raw_value() - return a gpio's raw value |
2211 | * @desc: gpio whose value will be returned | |
d2876d08 | 2212 | * |
79a9becd AC |
2213 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding |
2214 | * its ACTIVE_LOW status. | |
2215 | * | |
2216 | * This function should be called from contexts where we cannot sleep, and will | |
2217 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 2218 | */ |
79a9becd | 2219 | int gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 | 2220 | { |
bcabdef1 AC |
2221 | if (!desc) |
2222 | return 0; | |
e4e449e8 | 2223 | /* Should be using gpio_get_value_cansleep() */ |
d8e0ac08 | 2224 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 2225 | return _gpiod_get_raw_value(desc); |
d2876d08 | 2226 | } |
79a9becd | 2227 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value); |
372e722e | 2228 | |
79a9becd AC |
2229 | /** |
2230 | * gpiod_get_value() - return a gpio's value | |
2231 | * @desc: gpio whose value will be returned | |
2232 | * | |
2233 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
2234 | * account. | |
2235 | * | |
2236 | * This function should be called from contexts where we cannot sleep, and will | |
2237 | * complain if the GPIO chip functions potentially sleep. | |
2238 | */ | |
2239 | int gpiod_get_value(const struct gpio_desc *desc) | |
372e722e | 2240 | { |
79a9becd AC |
2241 | int value; |
2242 | if (!desc) | |
2243 | return 0; | |
2244 | /* Should be using gpio_get_value_cansleep() */ | |
2245 | WARN_ON(desc->chip->can_sleep); | |
2246 | ||
2247 | value = _gpiod_get_raw_value(desc); | |
2248 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2249 | value = !value; | |
2250 | ||
2251 | return value; | |
372e722e | 2252 | } |
79a9becd | 2253 | EXPORT_SYMBOL_GPL(gpiod_get_value); |
d2876d08 | 2254 | |
aca5ce14 LD |
2255 | /* |
2256 | * _gpio_set_open_drain_value() - Set the open drain gpio's value. | |
79a9becd | 2257 | * @desc: gpio descriptor whose state need to be set. |
aca5ce14 LD |
2258 | * @value: Non-zero for setting it HIGH otherise it will set to LOW. |
2259 | */ | |
23600969 | 2260 | static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value) |
aca5ce14 LD |
2261 | { |
2262 | int err = 0; | |
372e722e AC |
2263 | struct gpio_chip *chip = desc->chip; |
2264 | int offset = gpio_chip_hwgpio(desc); | |
2265 | ||
aca5ce14 | 2266 | if (value) { |
372e722e | 2267 | err = chip->direction_input(chip, offset); |
aca5ce14 | 2268 | if (!err) |
372e722e | 2269 | clear_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 2270 | } else { |
372e722e | 2271 | err = chip->direction_output(chip, offset, 0); |
aca5ce14 | 2272 | if (!err) |
372e722e | 2273 | set_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 2274 | } |
372e722e | 2275 | trace_gpio_direction(desc_to_gpio(desc), value, err); |
aca5ce14 | 2276 | if (err < 0) |
6424de5a MB |
2277 | gpiod_err(desc, |
2278 | "%s: Error in set_value for open drain err %d\n", | |
2279 | __func__, err); | |
aca5ce14 LD |
2280 | } |
2281 | ||
25553ff0 | 2282 | /* |
79a9becd AC |
2283 | * _gpio_set_open_source_value() - Set the open source gpio's value. |
2284 | * @desc: gpio descriptor whose state need to be set. | |
25553ff0 LD |
2285 | * @value: Non-zero for setting it HIGH otherise it will set to LOW. |
2286 | */ | |
23600969 | 2287 | static void _gpio_set_open_source_value(struct gpio_desc *desc, bool value) |
25553ff0 LD |
2288 | { |
2289 | int err = 0; | |
372e722e AC |
2290 | struct gpio_chip *chip = desc->chip; |
2291 | int offset = gpio_chip_hwgpio(desc); | |
2292 | ||
25553ff0 | 2293 | if (value) { |
372e722e | 2294 | err = chip->direction_output(chip, offset, 1); |
25553ff0 | 2295 | if (!err) |
372e722e | 2296 | set_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 2297 | } else { |
372e722e | 2298 | err = chip->direction_input(chip, offset); |
25553ff0 | 2299 | if (!err) |
372e722e | 2300 | clear_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 2301 | } |
372e722e | 2302 | trace_gpio_direction(desc_to_gpio(desc), !value, err); |
25553ff0 | 2303 | if (err < 0) |
6424de5a MB |
2304 | gpiod_err(desc, |
2305 | "%s: Error in set_value for open source err %d\n", | |
2306 | __func__, err); | |
25553ff0 LD |
2307 | } |
2308 | ||
23600969 | 2309 | static void _gpiod_set_raw_value(struct gpio_desc *desc, bool value) |
d2876d08 DB |
2310 | { |
2311 | struct gpio_chip *chip; | |
2312 | ||
372e722e | 2313 | chip = desc->chip; |
372e722e AC |
2314 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
2315 | if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
2316 | _gpio_set_open_drain_value(desc, value); | |
2317 | else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
2318 | _gpio_set_open_source_value(desc, value); | |
aca5ce14 | 2319 | else |
372e722e AC |
2320 | chip->set(chip, gpio_chip_hwgpio(desc), value); |
2321 | } | |
2322 | ||
d2876d08 | 2323 | /** |
79a9becd AC |
2324 | * gpiod_set_raw_value() - assign a gpio's raw value |
2325 | * @desc: gpio whose value will be assigned | |
d2876d08 | 2326 | * @value: value to assign |
d2876d08 | 2327 | * |
79a9becd AC |
2328 | * Set the raw value of the GPIO, i.e. the value of its physical line without |
2329 | * regard for its ACTIVE_LOW status. | |
2330 | * | |
2331 | * This function should be called from contexts where we cannot sleep, and will | |
2332 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 2333 | */ |
79a9becd | 2334 | void gpiod_set_raw_value(struct gpio_desc *desc, int value) |
372e722e | 2335 | { |
bcabdef1 AC |
2336 | if (!desc) |
2337 | return; | |
e4e449e8 | 2338 | /* Should be using gpio_set_value_cansleep() */ |
d8e0ac08 | 2339 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 2340 | _gpiod_set_raw_value(desc, value); |
d2876d08 | 2341 | } |
79a9becd | 2342 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value); |
d2876d08 DB |
2343 | |
2344 | /** | |
79a9becd AC |
2345 | * gpiod_set_value() - assign a gpio's value |
2346 | * @desc: gpio whose value will be assigned | |
2347 | * @value: value to assign | |
2348 | * | |
2349 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
2350 | * account | |
d2876d08 | 2351 | * |
79a9becd AC |
2352 | * This function should be called from contexts where we cannot sleep, and will |
2353 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 2354 | */ |
79a9becd | 2355 | void gpiod_set_value(struct gpio_desc *desc, int value) |
d2876d08 | 2356 | { |
bcabdef1 | 2357 | if (!desc) |
79a9becd AC |
2358 | return; |
2359 | /* Should be using gpio_set_value_cansleep() */ | |
2360 | WARN_ON(desc->chip->can_sleep); | |
2361 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2362 | value = !value; | |
2363 | _gpiod_set_raw_value(desc, value); | |
372e722e | 2364 | } |
79a9becd | 2365 | EXPORT_SYMBOL_GPL(gpiod_set_value); |
d2876d08 | 2366 | |
d2876d08 | 2367 | /** |
79a9becd AC |
2368 | * gpiod_cansleep() - report whether gpio value access may sleep |
2369 | * @desc: gpio to check | |
d2876d08 | 2370 | * |
d2876d08 | 2371 | */ |
79a9becd | 2372 | int gpiod_cansleep(const struct gpio_desc *desc) |
372e722e | 2373 | { |
bcabdef1 AC |
2374 | if (!desc) |
2375 | return 0; | |
372e722e | 2376 | return desc->chip->can_sleep; |
d2876d08 | 2377 | } |
79a9becd | 2378 | EXPORT_SYMBOL_GPL(gpiod_cansleep); |
d2876d08 | 2379 | |
0f6d504e | 2380 | /** |
79a9becd AC |
2381 | * gpiod_to_irq() - return the IRQ corresponding to a GPIO |
2382 | * @desc: gpio whose IRQ will be returned (already requested) | |
0f6d504e | 2383 | * |
79a9becd AC |
2384 | * Return the IRQ corresponding to the passed GPIO, or an error code in case of |
2385 | * error. | |
0f6d504e | 2386 | */ |
79a9becd | 2387 | int gpiod_to_irq(const struct gpio_desc *desc) |
0f6d504e DB |
2388 | { |
2389 | struct gpio_chip *chip; | |
372e722e | 2390 | int offset; |
0f6d504e | 2391 | |
bcabdef1 AC |
2392 | if (!desc) |
2393 | return -EINVAL; | |
372e722e AC |
2394 | chip = desc->chip; |
2395 | offset = gpio_chip_hwgpio(desc); | |
2396 | return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO; | |
0f6d504e | 2397 | } |
79a9becd | 2398 | EXPORT_SYMBOL_GPL(gpiod_to_irq); |
0f6d504e | 2399 | |
d468bf9e LW |
2400 | /** |
2401 | * gpiod_lock_as_irq() - lock a GPIO to be used as IRQ | |
2402 | * @gpio: the GPIO line to lock as used for IRQ | |
2403 | * | |
2404 | * This is used directly by GPIO drivers that want to lock down | |
f438acdf | 2405 | * a certain GPIO line to be used for IRQs. |
d468bf9e | 2406 | */ |
79a9becd | 2407 | int gpiod_lock_as_irq(struct gpio_desc *desc) |
372e722e | 2408 | { |
d468bf9e LW |
2409 | if (!desc) |
2410 | return -EINVAL; | |
2411 | ||
2412 | if (test_bit(FLAG_IS_OUT, &desc->flags)) { | |
2413 | gpiod_err(desc, | |
2414 | "%s: tried to flag a GPIO set as output for IRQ\n", | |
2415 | __func__); | |
2416 | return -EIO; | |
2417 | } | |
2418 | ||
2419 | set_bit(FLAG_USED_AS_IRQ, &desc->flags); | |
2420 | return 0; | |
372e722e | 2421 | } |
79a9becd | 2422 | EXPORT_SYMBOL_GPL(gpiod_lock_as_irq); |
d2876d08 | 2423 | |
d468bf9e LW |
2424 | int gpio_lock_as_irq(struct gpio_chip *chip, unsigned int offset) |
2425 | { | |
bb1e88cc | 2426 | return gpiod_lock_as_irq(gpiochip_get_desc(chip, offset)); |
d468bf9e LW |
2427 | } |
2428 | EXPORT_SYMBOL_GPL(gpio_lock_as_irq); | |
d2876d08 | 2429 | |
d468bf9e LW |
2430 | /** |
2431 | * gpiod_unlock_as_irq() - unlock a GPIO used as IRQ | |
2432 | * @gpio: the GPIO line to unlock from IRQ usage | |
2433 | * | |
2434 | * This is used directly by GPIO drivers that want to indicate | |
2435 | * that a certain GPIO is no longer used exclusively for IRQ. | |
d2876d08 | 2436 | */ |
79a9becd | 2437 | void gpiod_unlock_as_irq(struct gpio_desc *desc) |
d468bf9e LW |
2438 | { |
2439 | if (!desc) | |
2440 | return; | |
d2876d08 | 2441 | |
d468bf9e LW |
2442 | clear_bit(FLAG_USED_AS_IRQ, &desc->flags); |
2443 | } | |
79a9becd | 2444 | EXPORT_SYMBOL_GPL(gpiod_unlock_as_irq); |
d468bf9e LW |
2445 | |
2446 | void gpio_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) | |
2447 | { | |
bb1e88cc | 2448 | return gpiod_unlock_as_irq(gpiochip_get_desc(chip, offset)); |
d468bf9e LW |
2449 | } |
2450 | EXPORT_SYMBOL_GPL(gpio_unlock_as_irq); | |
d2876d08 | 2451 | |
79a9becd AC |
2452 | /** |
2453 | * gpiod_get_raw_value_cansleep() - return a gpio's raw value | |
2454 | * @desc: gpio whose value will be returned | |
2455 | * | |
2456 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding | |
2457 | * its ACTIVE_LOW status. | |
2458 | * | |
2459 | * This function is to be called from contexts that can sleep. | |
d2876d08 | 2460 | */ |
79a9becd | 2461 | int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) |
d2876d08 | 2462 | { |
d2876d08 | 2463 | might_sleep_if(extra_checks); |
bcabdef1 AC |
2464 | if (!desc) |
2465 | return 0; | |
79a9becd | 2466 | return _gpiod_get_raw_value(desc); |
d2876d08 | 2467 | } |
79a9becd | 2468 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); |
372e722e | 2469 | |
79a9becd AC |
2470 | /** |
2471 | * gpiod_get_value_cansleep() - return a gpio's value | |
2472 | * @desc: gpio whose value will be returned | |
2473 | * | |
2474 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
2475 | * account. | |
2476 | * | |
2477 | * This function is to be called from contexts that can sleep. | |
2478 | */ | |
2479 | int gpiod_get_value_cansleep(const struct gpio_desc *desc) | |
d2876d08 | 2480 | { |
3f397c21 | 2481 | int value; |
d2876d08 DB |
2482 | |
2483 | might_sleep_if(extra_checks); | |
bcabdef1 AC |
2484 | if (!desc) |
2485 | return 0; | |
79a9becd AC |
2486 | |
2487 | value = _gpiod_get_raw_value(desc); | |
2488 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2489 | value = !value; | |
2490 | ||
3f397c21 | 2491 | return value; |
d2876d08 | 2492 | } |
79a9becd | 2493 | EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); |
372e722e | 2494 | |
79a9becd AC |
2495 | /** |
2496 | * gpiod_set_raw_value_cansleep() - assign a gpio's raw value | |
2497 | * @desc: gpio whose value will be assigned | |
2498 | * @value: value to assign | |
2499 | * | |
2500 | * Set the raw value of the GPIO, i.e. the value of its physical line without | |
2501 | * regard for its ACTIVE_LOW status. | |
2502 | * | |
2503 | * This function is to be called from contexts that can sleep. | |
2504 | */ | |
2505 | void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) | |
372e722e | 2506 | { |
d2876d08 | 2507 | might_sleep_if(extra_checks); |
bcabdef1 AC |
2508 | if (!desc) |
2509 | return; | |
79a9becd | 2510 | _gpiod_set_raw_value(desc, value); |
372e722e | 2511 | } |
79a9becd | 2512 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); |
d2876d08 | 2513 | |
79a9becd AC |
2514 | /** |
2515 | * gpiod_set_value_cansleep() - assign a gpio's value | |
2516 | * @desc: gpio whose value will be assigned | |
2517 | * @value: value to assign | |
2518 | * | |
2519 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
2520 | * account | |
2521 | * | |
2522 | * This function is to be called from contexts that can sleep. | |
2523 | */ | |
2524 | void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) | |
d2876d08 | 2525 | { |
d2876d08 | 2526 | might_sleep_if(extra_checks); |
bcabdef1 AC |
2527 | if (!desc) |
2528 | return; | |
79a9becd AC |
2529 | |
2530 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2531 | value = !value; | |
2532 | _gpiod_set_raw_value(desc, value); | |
372e722e | 2533 | } |
79a9becd | 2534 | EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); |
d2876d08 | 2535 | |
bae48da2 | 2536 | /** |
ad824783 AC |
2537 | * gpiod_add_lookup_table() - register GPIO device consumers |
2538 | * @table: table of consumers to register | |
bae48da2 | 2539 | */ |
ad824783 | 2540 | void gpiod_add_lookup_table(struct gpiod_lookup_table *table) |
bae48da2 AC |
2541 | { |
2542 | mutex_lock(&gpio_lookup_lock); | |
2543 | ||
ad824783 | 2544 | list_add_tail(&table->list, &gpio_lookup_list); |
bae48da2 AC |
2545 | |
2546 | mutex_unlock(&gpio_lookup_lock); | |
2547 | } | |
2548 | ||
bae48da2 AC |
2549 | #ifdef CONFIG_OF |
2550 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, | |
53e7cac3 AC |
2551 | unsigned int idx, |
2552 | enum gpio_lookup_flags *flags) | |
bae48da2 AC |
2553 | { |
2554 | char prop_name[32]; /* 32 is max size of property name */ | |
2555 | enum of_gpio_flags of_flags; | |
2556 | struct gpio_desc *desc; | |
2557 | ||
2558 | if (con_id) | |
2559 | snprintf(prop_name, 32, "%s-gpios", con_id); | |
aca5ce14 | 2560 | else |
bae48da2 AC |
2561 | snprintf(prop_name, 32, "gpios"); |
2562 | ||
2563 | desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx, | |
2564 | &of_flags); | |
2565 | ||
2566 | if (IS_ERR(desc)) | |
2567 | return desc; | |
2568 | ||
2569 | if (of_flags & OF_GPIO_ACTIVE_LOW) | |
53e7cac3 | 2570 | *flags |= GPIO_ACTIVE_LOW; |
bae48da2 AC |
2571 | |
2572 | return desc; | |
2573 | } | |
2574 | #else | |
2575 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, | |
209e64f9 AC |
2576 | unsigned int idx, |
2577 | enum gpio_lookup_flags *flags) | |
bae48da2 AC |
2578 | { |
2579 | return ERR_PTR(-ENODEV); | |
d2876d08 | 2580 | } |
bae48da2 | 2581 | #endif |
d2876d08 | 2582 | |
81f59e9d | 2583 | static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id, |
53e7cac3 AC |
2584 | unsigned int idx, |
2585 | enum gpio_lookup_flags *flags) | |
372e722e | 2586 | { |
e01f440a MW |
2587 | struct acpi_gpio_info info; |
2588 | struct gpio_desc *desc; | |
2589 | ||
2590 | desc = acpi_get_gpiod_by_index(dev, idx, &info); | |
2591 | if (IS_ERR(desc)) | |
2592 | return desc; | |
2593 | ||
2594 | if (info.gpioint && info.active_low) | |
53e7cac3 | 2595 | *flags |= GPIO_ACTIVE_LOW; |
e01f440a MW |
2596 | |
2597 | return desc; | |
81f59e9d MW |
2598 | } |
2599 | ||
ad824783 | 2600 | static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) |
bae48da2 AC |
2601 | { |
2602 | const char *dev_id = dev ? dev_name(dev) : NULL; | |
ad824783 | 2603 | struct gpiod_lookup_table *table; |
bae48da2 AC |
2604 | |
2605 | mutex_lock(&gpio_lookup_lock); | |
2606 | ||
ad824783 AC |
2607 | list_for_each_entry(table, &gpio_lookup_list, list) { |
2608 | if (table->dev_id && dev_id) { | |
2609 | /* | |
2610 | * Valid strings on both ends, must be identical to have | |
2611 | * a match | |
2612 | */ | |
2613 | if (!strcmp(table->dev_id, dev_id)) | |
2614 | goto found; | |
2615 | } else { | |
2616 | /* | |
2617 | * One of the pointers is NULL, so both must be to have | |
2618 | * a match | |
2619 | */ | |
2620 | if (dev_id == table->dev_id) | |
2621 | goto found; | |
2622 | } | |
2623 | } | |
2624 | table = NULL; | |
bae48da2 | 2625 | |
ad824783 AC |
2626 | found: |
2627 | mutex_unlock(&gpio_lookup_lock); | |
2628 | return table; | |
2629 | } | |
bae48da2 | 2630 | |
ad824783 AC |
2631 | static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, |
2632 | unsigned int idx, | |
2633 | enum gpio_lookup_flags *flags) | |
2634 | { | |
2a3cf6a3 | 2635 | struct gpio_desc *desc = ERR_PTR(-ENOENT); |
ad824783 AC |
2636 | struct gpiod_lookup_table *table; |
2637 | struct gpiod_lookup *p; | |
bae48da2 | 2638 | |
ad824783 AC |
2639 | table = gpiod_find_lookup_table(dev); |
2640 | if (!table) | |
2641 | return desc; | |
bae48da2 | 2642 | |
ad824783 AC |
2643 | for (p = &table->table[0]; p->chip_label; p++) { |
2644 | struct gpio_chip *chip; | |
bae48da2 | 2645 | |
ad824783 | 2646 | /* idx must always match exactly */ |
bae48da2 AC |
2647 | if (p->idx != idx) |
2648 | continue; | |
2649 | ||
ad824783 AC |
2650 | /* If the lookup entry has a con_id, require exact match */ |
2651 | if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) | |
2652 | continue; | |
bae48da2 | 2653 | |
ad824783 | 2654 | chip = find_chip_by_name(p->chip_label); |
bae48da2 | 2655 | |
ad824783 | 2656 | if (!chip) { |
2a3cf6a3 AC |
2657 | dev_err(dev, "cannot find GPIO chip %s\n", |
2658 | p->chip_label); | |
2659 | return ERR_PTR(-ENODEV); | |
ad824783 | 2660 | } |
bae48da2 | 2661 | |
ad824783 | 2662 | if (chip->ngpio <= p->chip_hwnum) { |
2a3cf6a3 AC |
2663 | dev_err(dev, |
2664 | "requested GPIO %d is out of range [0..%d] for chip %s\n", | |
2665 | idx, chip->ngpio, chip->label); | |
2666 | return ERR_PTR(-EINVAL); | |
bae48da2 | 2667 | } |
bae48da2 | 2668 | |
bb1e88cc | 2669 | desc = gpiochip_get_desc(chip, p->chip_hwnum); |
ad824783 | 2670 | *flags = p->flags; |
bae48da2 | 2671 | |
2a3cf6a3 | 2672 | return desc; |
bae48da2 AC |
2673 | } |
2674 | ||
bae48da2 AC |
2675 | return desc; |
2676 | } | |
2677 | ||
2678 | /** | |
2679 | * gpio_get - obtain a GPIO for a given GPIO function | |
ad824783 | 2680 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 AC |
2681 | * @con_id: function within the GPIO consumer |
2682 | * | |
2683 | * Return the GPIO descriptor corresponding to the function con_id of device | |
2a3cf6a3 AC |
2684 | * dev, -ENOENT if no GPIO has been assigned to the requested function, or |
2685 | * another IS_ERR() code if an error occured while trying to acquire the GPIO. | |
bae48da2 AC |
2686 | */ |
2687 | struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id) | |
2688 | { | |
2689 | return gpiod_get_index(dev, con_id, 0); | |
2690 | } | |
2691 | EXPORT_SYMBOL_GPL(gpiod_get); | |
2692 | ||
2693 | /** | |
2694 | * gpiod_get_index - obtain a GPIO from a multi-index GPIO function | |
fdd6a5fe | 2695 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 AC |
2696 | * @con_id: function within the GPIO consumer |
2697 | * @idx: index of the GPIO to obtain in the consumer | |
2698 | * | |
2699 | * This variant of gpiod_get() allows to access GPIOs other than the first | |
2700 | * defined one for functions that define several GPIOs. | |
2701 | * | |
2a3cf6a3 AC |
2702 | * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the |
2703 | * requested function and/or index, or another IS_ERR() code if an error | |
2704 | * occured while trying to acquire the GPIO. | |
bae48da2 AC |
2705 | */ |
2706 | struct gpio_desc *__must_check gpiod_get_index(struct device *dev, | |
2707 | const char *con_id, | |
2708 | unsigned int idx) | |
2709 | { | |
35c5d7fd | 2710 | struct gpio_desc *desc = NULL; |
bae48da2 | 2711 | int status; |
53e7cac3 | 2712 | enum gpio_lookup_flags flags = 0; |
bae48da2 AC |
2713 | |
2714 | dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); | |
2715 | ||
2716 | /* Using device tree? */ | |
2717 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) { | |
2718 | dev_dbg(dev, "using device tree for GPIO lookup\n"); | |
2719 | desc = of_find_gpio(dev, con_id, idx, &flags); | |
81f59e9d MW |
2720 | } else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) { |
2721 | dev_dbg(dev, "using ACPI for GPIO lookup\n"); | |
2722 | desc = acpi_find_gpio(dev, con_id, idx, &flags); | |
35c5d7fd AC |
2723 | } |
2724 | ||
2725 | /* | |
2726 | * Either we are not using DT or ACPI, or their lookup did not return | |
2727 | * a result. In that case, use platform lookup as a fallback. | |
2728 | */ | |
2a3cf6a3 | 2729 | if (!desc || desc == ERR_PTR(-ENOENT)) { |
bae48da2 | 2730 | dev_dbg(dev, "using lookup tables for GPIO lookup"); |
2a3cf6a3 | 2731 | desc = gpiod_find(dev, con_id, idx, &flags); |
bae48da2 AC |
2732 | } |
2733 | ||
2734 | if (IS_ERR(desc)) { | |
351cfe0f | 2735 | dev_dbg(dev, "lookup for GPIO %s failed\n", con_id); |
bae48da2 AC |
2736 | return desc; |
2737 | } | |
2738 | ||
2739 | status = gpiod_request(desc, con_id); | |
2740 | ||
2741 | if (status < 0) | |
2742 | return ERR_PTR(status); | |
2743 | ||
53e7cac3 | 2744 | if (flags & GPIO_ACTIVE_LOW) |
bae48da2 | 2745 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); |
53e7cac3 AC |
2746 | if (flags & GPIO_OPEN_DRAIN) |
2747 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); | |
2748 | if (flags & GPIO_OPEN_SOURCE) | |
2749 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); | |
bae48da2 AC |
2750 | |
2751 | return desc; | |
2752 | } | |
2753 | EXPORT_SYMBOL_GPL(gpiod_get_index); | |
2754 | ||
2755 | /** | |
2756 | * gpiod_put - dispose of a GPIO descriptor | |
2757 | * @desc: GPIO descriptor to dispose of | |
2758 | * | |
2759 | * No descriptor can be used after gpiod_put() has been called on it. | |
2760 | */ | |
2761 | void gpiod_put(struct gpio_desc *desc) | |
2762 | { | |
2763 | gpiod_free(desc); | |
372e722e | 2764 | } |
bae48da2 | 2765 | EXPORT_SYMBOL_GPL(gpiod_put); |
d2876d08 DB |
2766 | |
2767 | #ifdef CONFIG_DEBUG_FS | |
2768 | ||
d2876d08 DB |
2769 | static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip) |
2770 | { | |
2771 | unsigned i; | |
2772 | unsigned gpio = chip->base; | |
6c0b4e6c | 2773 | struct gpio_desc *gdesc = &chip->desc[0]; |
d2876d08 | 2774 | int is_out; |
d468bf9e | 2775 | int is_irq; |
d2876d08 DB |
2776 | |
2777 | for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) { | |
2778 | if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) | |
2779 | continue; | |
2780 | ||
372e722e | 2781 | gpiod_get_direction(gdesc); |
d2876d08 | 2782 | is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); |
d468bf9e LW |
2783 | is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); |
2784 | seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s", | |
d2876d08 DB |
2785 | gpio, gdesc->label, |
2786 | is_out ? "out" : "in ", | |
2787 | chip->get | |
2788 | ? (chip->get(chip, i) ? "hi" : "lo") | |
d468bf9e LW |
2789 | : "? ", |
2790 | is_irq ? "IRQ" : " "); | |
d2876d08 DB |
2791 | seq_printf(s, "\n"); |
2792 | } | |
2793 | } | |
2794 | ||
f9c4a31f | 2795 | static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) |
d2876d08 | 2796 | { |
362432ae | 2797 | unsigned long flags; |
f9c4a31f | 2798 | struct gpio_chip *chip = NULL; |
cb1650d4 | 2799 | loff_t index = *pos; |
d2876d08 | 2800 | |
f9c4a31f | 2801 | s->private = ""; |
d2876d08 | 2802 | |
362432ae | 2803 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 | 2804 | list_for_each_entry(chip, &gpio_chips, list) |
362432ae GL |
2805 | if (index-- == 0) { |
2806 | spin_unlock_irqrestore(&gpio_lock, flags); | |
cb1650d4 | 2807 | return chip; |
f9c4a31f | 2808 | } |
362432ae | 2809 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f | 2810 | |
cb1650d4 | 2811 | return NULL; |
f9c4a31f TR |
2812 | } |
2813 | ||
2814 | static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
2815 | { | |
362432ae | 2816 | unsigned long flags; |
f9c4a31f | 2817 | struct gpio_chip *chip = v; |
f9c4a31f TR |
2818 | void *ret = NULL; |
2819 | ||
362432ae | 2820 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 AC |
2821 | if (list_is_last(&chip->list, &gpio_chips)) |
2822 | ret = NULL; | |
2823 | else | |
2824 | ret = list_entry(chip->list.next, struct gpio_chip, list); | |
362432ae | 2825 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f TR |
2826 | |
2827 | s->private = "\n"; | |
2828 | ++*pos; | |
2829 | ||
2830 | return ret; | |
2831 | } | |
2832 | ||
2833 | static void gpiolib_seq_stop(struct seq_file *s, void *v) | |
2834 | { | |
2835 | } | |
2836 | ||
2837 | static int gpiolib_seq_show(struct seq_file *s, void *v) | |
2838 | { | |
2839 | struct gpio_chip *chip = v; | |
2840 | struct device *dev; | |
2841 | ||
2842 | seq_printf(s, "%sGPIOs %d-%d", (char *)s->private, | |
2843 | chip->base, chip->base + chip->ngpio - 1); | |
2844 | dev = chip->dev; | |
2845 | if (dev) | |
2846 | seq_printf(s, ", %s/%s", dev->bus ? dev->bus->name : "no-bus", | |
2847 | dev_name(dev)); | |
2848 | if (chip->label) | |
2849 | seq_printf(s, ", %s", chip->label); | |
2850 | if (chip->can_sleep) | |
2851 | seq_printf(s, ", can sleep"); | |
2852 | seq_printf(s, ":\n"); | |
2853 | ||
2854 | if (chip->dbg_show) | |
2855 | chip->dbg_show(s, chip); | |
2856 | else | |
2857 | gpiolib_dbg_show(s, chip); | |
2858 | ||
d2876d08 DB |
2859 | return 0; |
2860 | } | |
2861 | ||
f9c4a31f TR |
2862 | static const struct seq_operations gpiolib_seq_ops = { |
2863 | .start = gpiolib_seq_start, | |
2864 | .next = gpiolib_seq_next, | |
2865 | .stop = gpiolib_seq_stop, | |
2866 | .show = gpiolib_seq_show, | |
2867 | }; | |
2868 | ||
d2876d08 DB |
2869 | static int gpiolib_open(struct inode *inode, struct file *file) |
2870 | { | |
f9c4a31f | 2871 | return seq_open(file, &gpiolib_seq_ops); |
d2876d08 DB |
2872 | } |
2873 | ||
828c0950 | 2874 | static const struct file_operations gpiolib_operations = { |
f9c4a31f | 2875 | .owner = THIS_MODULE, |
d2876d08 DB |
2876 | .open = gpiolib_open, |
2877 | .read = seq_read, | |
2878 | .llseek = seq_lseek, | |
f9c4a31f | 2879 | .release = seq_release, |
d2876d08 DB |
2880 | }; |
2881 | ||
2882 | static int __init gpiolib_debugfs_init(void) | |
2883 | { | |
2884 | /* /sys/kernel/debug/gpio */ | |
2885 | (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO, | |
2886 | NULL, NULL, &gpiolib_operations); | |
2887 | return 0; | |
2888 | } | |
2889 | subsys_initcall(gpiolib_debugfs_init); | |
2890 | ||
2891 | #endif /* DEBUG_FS */ |