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Commit | Line | Data |
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d2876d08 DB |
1 | #include <linux/kernel.h> |
2 | #include <linux/module.h> | |
ff77c352 | 3 | #include <linux/interrupt.h> |
d2876d08 DB |
4 | #include <linux/irq.h> |
5 | #include <linux/spinlock.h> | |
1a989d0f | 6 | #include <linux/list.h> |
d8f388d8 DB |
7 | #include <linux/device.h> |
8 | #include <linux/err.h> | |
9 | #include <linux/debugfs.h> | |
10 | #include <linux/seq_file.h> | |
11 | #include <linux/gpio.h> | |
391c970c | 12 | #include <linux/of_gpio.h> |
ff77c352 | 13 | #include <linux/idr.h> |
5a0e3ad6 | 14 | #include <linux/slab.h> |
7b199811 | 15 | #include <linux/acpi.h> |
53e7cac3 | 16 | #include <linux/gpio/driver.h> |
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 LW |
166 | /** |
167 | * Convert an offset on a certain chip to a corresponding descriptor | |
168 | */ | |
169 | static struct gpio_desc *gpiochip_offset_to_desc(struct gpio_chip *chip, | |
170 | unsigned int offset) | |
171 | { | |
b7d0a28a AC |
172 | if (offset >= chip->ngpio) |
173 | return ERR_PTR(-EINVAL); | |
d468bf9e | 174 | |
b7d0a28a | 175 | return &chip->desc[offset]; |
d468bf9e | 176 | } |
372e722e AC |
177 | |
178 | /** | |
179 | * Convert a GPIO descriptor to the integer namespace. | |
180 | * This should disappear in the future but is needed since we still | |
181 | * use GPIO numbers for error messages and sysfs nodes | |
182 | */ | |
79a9becd | 183 | int desc_to_gpio(const struct gpio_desc *desc) |
372e722e | 184 | { |
8c0fca81 | 185 | return desc - &gpio_desc[0]; |
372e722e | 186 | } |
79a9becd | 187 | EXPORT_SYMBOL_GPL(desc_to_gpio); |
372e722e AC |
188 | |
189 | ||
d2876d08 DB |
190 | /* Warn when drivers omit gpio_request() calls -- legal but ill-advised |
191 | * when setting direction, and otherwise illegal. Until board setup code | |
192 | * and drivers use explicit requests everywhere (which won't happen when | |
193 | * those calls have no teeth) we can't avoid autorequesting. This nag | |
35e8bb51 DB |
194 | * message should motivate switching to explicit requests... so should |
195 | * the weaker cleanup after faults, compared to gpio_request(). | |
8a0cecff DB |
196 | * |
197 | * NOTE: the autorequest mechanism is going away; at this point it's | |
198 | * only "legal" in the sense that (old) code using it won't break yet, | |
199 | * but instead only triggers a WARN() stack dump. | |
d2876d08 | 200 | */ |
372e722e | 201 | static int gpio_ensure_requested(struct gpio_desc *desc) |
d2876d08 | 202 | { |
8a0cecff | 203 | const struct gpio_chip *chip = desc->chip; |
372e722e | 204 | const int gpio = desc_to_gpio(desc); |
35e8bb51 | 205 | |
8a0cecff DB |
206 | if (WARN(test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0, |
207 | "autorequest GPIO-%d\n", gpio)) { | |
35e8bb51 | 208 | if (!try_module_get(chip->owner)) { |
7589e59f AS |
209 | gpiod_err(desc, "%s: module can't be gotten\n", |
210 | __func__); | |
35e8bb51 DB |
211 | clear_bit(FLAG_REQUESTED, &desc->flags); |
212 | /* lose */ | |
213 | return -EIO; | |
214 | } | |
d2876d08 | 215 | desc_set_label(desc, "[auto]"); |
35e8bb51 DB |
216 | /* caller must chip->request() w/o spinlock */ |
217 | if (chip->request) | |
218 | return 1; | |
d2876d08 | 219 | } |
35e8bb51 | 220 | return 0; |
d2876d08 DB |
221 | } |
222 | ||
79a9becd AC |
223 | /** |
224 | * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs | |
225 | * @desc: descriptor to return the chip of | |
226 | */ | |
227 | struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) | |
372e722e | 228 | { |
bcabdef1 | 229 | return desc ? desc->chip : NULL; |
372e722e | 230 | } |
79a9becd | 231 | EXPORT_SYMBOL_GPL(gpiod_to_chip); |
d2876d08 | 232 | |
8d0aab2f AV |
233 | /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ |
234 | static int gpiochip_find_base(int ngpio) | |
235 | { | |
83cabe33 AC |
236 | struct gpio_chip *chip; |
237 | int base = ARCH_NR_GPIOS - ngpio; | |
8d0aab2f | 238 | |
83cabe33 AC |
239 | list_for_each_entry_reverse(chip, &gpio_chips, list) { |
240 | /* found a free space? */ | |
241 | if (chip->base + chip->ngpio <= base) | |
242 | break; | |
243 | else | |
244 | /* nope, check the space right before the chip */ | |
245 | base = chip->base - ngpio; | |
8d0aab2f AV |
246 | } |
247 | ||
83cabe33 | 248 | if (gpio_is_valid(base)) { |
8d0aab2f | 249 | pr_debug("%s: found new base at %d\n", __func__, base); |
83cabe33 AC |
250 | return base; |
251 | } else { | |
252 | pr_err("%s: cannot find free range\n", __func__); | |
253 | return -ENOSPC; | |
169b6a7a | 254 | } |
169b6a7a AV |
255 | } |
256 | ||
79a9becd AC |
257 | /** |
258 | * gpiod_get_direction - return the current direction of a GPIO | |
259 | * @desc: GPIO to get the direction of | |
260 | * | |
261 | * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error. | |
262 | * | |
263 | * This function may sleep if gpiod_cansleep() is true. | |
264 | */ | |
265 | int gpiod_get_direction(const struct gpio_desc *desc) | |
80b0a602 MN |
266 | { |
267 | struct gpio_chip *chip; | |
372e722e | 268 | unsigned offset; |
80b0a602 MN |
269 | int status = -EINVAL; |
270 | ||
372e722e AC |
271 | chip = gpiod_to_chip(desc); |
272 | offset = gpio_chip_hwgpio(desc); | |
80b0a602 MN |
273 | |
274 | if (!chip->get_direction) | |
275 | return status; | |
276 | ||
372e722e | 277 | status = chip->get_direction(chip, offset); |
80b0a602 MN |
278 | if (status > 0) { |
279 | /* GPIOF_DIR_IN, or other positive */ | |
280 | status = 1; | |
def63433 AC |
281 | /* FLAG_IS_OUT is just a cache of the result of get_direction(), |
282 | * so it does not affect constness per se */ | |
283 | clear_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); | |
80b0a602 MN |
284 | } |
285 | if (status == 0) { | |
286 | /* GPIOF_DIR_OUT */ | |
def63433 | 287 | set_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); |
80b0a602 MN |
288 | } |
289 | return status; | |
290 | } | |
79a9becd | 291 | EXPORT_SYMBOL_GPL(gpiod_get_direction); |
80b0a602 | 292 | |
d8f388d8 DB |
293 | #ifdef CONFIG_GPIO_SYSFS |
294 | ||
295 | /* lock protects against unexport_gpio() being called while | |
296 | * sysfs files are active. | |
297 | */ | |
298 | static DEFINE_MUTEX(sysfs_lock); | |
299 | ||
300 | /* | |
301 | * /sys/class/gpio/gpioN... only for GPIOs that are exported | |
302 | * /direction | |
303 | * * MAY BE OMITTED if kernel won't allow direction changes | |
304 | * * is read/write as "in" or "out" | |
305 | * * may also be written as "high" or "low", initializing | |
306 | * output value as specified ("out" implies "low") | |
307 | * /value | |
308 | * * always readable, subject to hardware behavior | |
309 | * * may be writable, as zero/nonzero | |
ff77c352 DG |
310 | * /edge |
311 | * * configures behavior of poll(2) on /value | |
312 | * * available only if pin can generate IRQs on input | |
313 | * * is read/write as "none", "falling", "rising", or "both" | |
07697461 JN |
314 | * /active_low |
315 | * * configures polarity of /value | |
316 | * * is read/write as zero/nonzero | |
317 | * * also affects existing and subsequent "falling" and "rising" | |
318 | * /edge configuration | |
d8f388d8 DB |
319 | */ |
320 | ||
321 | static ssize_t gpio_direction_show(struct device *dev, | |
322 | struct device_attribute *attr, char *buf) | |
323 | { | |
def63433 | 324 | const struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
325 | ssize_t status; |
326 | ||
327 | mutex_lock(&sysfs_lock); | |
328 | ||
476171ce | 329 | if (!test_bit(FLAG_EXPORT, &desc->flags)) { |
d8f388d8 | 330 | status = -EIO; |
476171ce | 331 | } else { |
372e722e | 332 | gpiod_get_direction(desc); |
d8f388d8 DB |
333 | status = sprintf(buf, "%s\n", |
334 | test_bit(FLAG_IS_OUT, &desc->flags) | |
335 | ? "out" : "in"); | |
476171ce | 336 | } |
d8f388d8 DB |
337 | |
338 | mutex_unlock(&sysfs_lock); | |
339 | return status; | |
340 | } | |
341 | ||
342 | static ssize_t gpio_direction_store(struct device *dev, | |
343 | struct device_attribute *attr, const char *buf, size_t size) | |
344 | { | |
372e722e | 345 | struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
346 | ssize_t status; |
347 | ||
348 | mutex_lock(&sysfs_lock); | |
349 | ||
350 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
351 | status = -EIO; | |
352 | else if (sysfs_streq(buf, "high")) | |
ef70bbe1 | 353 | status = gpiod_direction_output_raw(desc, 1); |
d8f388d8 | 354 | else if (sysfs_streq(buf, "out") || sysfs_streq(buf, "low")) |
ef70bbe1 | 355 | status = gpiod_direction_output_raw(desc, 0); |
d8f388d8 | 356 | else if (sysfs_streq(buf, "in")) |
372e722e | 357 | status = gpiod_direction_input(desc); |
d8f388d8 DB |
358 | else |
359 | status = -EINVAL; | |
360 | ||
361 | mutex_unlock(&sysfs_lock); | |
362 | return status ? : size; | |
363 | } | |
364 | ||
07697461 | 365 | static /* const */ DEVICE_ATTR(direction, 0644, |
d8f388d8 DB |
366 | gpio_direction_show, gpio_direction_store); |
367 | ||
368 | static ssize_t gpio_value_show(struct device *dev, | |
369 | struct device_attribute *attr, char *buf) | |
370 | { | |
372e722e | 371 | struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
372 | ssize_t status; |
373 | ||
374 | mutex_lock(&sysfs_lock); | |
375 | ||
79a9becd | 376 | if (!test_bit(FLAG_EXPORT, &desc->flags)) |
d8f388d8 | 377 | status = -EIO; |
79a9becd AC |
378 | else |
379 | status = sprintf(buf, "%d\n", gpiod_get_value_cansleep(desc)); | |
d8f388d8 DB |
380 | |
381 | mutex_unlock(&sysfs_lock); | |
382 | return status; | |
383 | } | |
384 | ||
385 | static ssize_t gpio_value_store(struct device *dev, | |
386 | struct device_attribute *attr, const char *buf, size_t size) | |
387 | { | |
372e722e | 388 | struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
389 | ssize_t status; |
390 | ||
391 | mutex_lock(&sysfs_lock); | |
392 | ||
393 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
394 | status = -EIO; | |
395 | else if (!test_bit(FLAG_IS_OUT, &desc->flags)) | |
396 | status = -EPERM; | |
397 | else { | |
398 | long value; | |
399 | ||
a3d88c92 | 400 | status = kstrtol(buf, 0, &value); |
d8f388d8 | 401 | if (status == 0) { |
79a9becd | 402 | gpiod_set_value_cansleep(desc, value); |
d8f388d8 DB |
403 | status = size; |
404 | } | |
405 | } | |
406 | ||
407 | mutex_unlock(&sysfs_lock); | |
408 | return status; | |
409 | } | |
410 | ||
07697461 | 411 | static const DEVICE_ATTR(value, 0644, |
d8f388d8 DB |
412 | gpio_value_show, gpio_value_store); |
413 | ||
ff77c352 DG |
414 | static irqreturn_t gpio_sysfs_irq(int irq, void *priv) |
415 | { | |
324a56e1 | 416 | struct kernfs_node *value_sd = priv; |
ff77c352 | 417 | |
5ba1821d | 418 | sysfs_notify_dirent(value_sd); |
ff77c352 DG |
419 | return IRQ_HANDLED; |
420 | } | |
421 | ||
ff77c352 DG |
422 | static int gpio_setup_irq(struct gpio_desc *desc, struct device *dev, |
423 | unsigned long gpio_flags) | |
424 | { | |
324a56e1 | 425 | struct kernfs_node *value_sd; |
ff77c352 DG |
426 | unsigned long irq_flags; |
427 | int ret, irq, id; | |
428 | ||
429 | if ((desc->flags & GPIO_TRIGGER_MASK) == gpio_flags) | |
430 | return 0; | |
431 | ||
372e722e | 432 | irq = gpiod_to_irq(desc); |
ff77c352 DG |
433 | if (irq < 0) |
434 | return -EIO; | |
435 | ||
5ba1821d DG |
436 | id = desc->flags >> ID_SHIFT; |
437 | value_sd = idr_find(&dirent_idr, id); | |
438 | if (value_sd) | |
439 | free_irq(irq, value_sd); | |
ff77c352 DG |
440 | |
441 | desc->flags &= ~GPIO_TRIGGER_MASK; | |
442 | ||
443 | if (!gpio_flags) { | |
d468bf9e | 444 | gpiod_unlock_as_irq(desc); |
ff77c352 | 445 | ret = 0; |
5ba1821d | 446 | goto free_id; |
ff77c352 DG |
447 | } |
448 | ||
449 | irq_flags = IRQF_SHARED; | |
450 | if (test_bit(FLAG_TRIG_FALL, &gpio_flags)) | |
07697461 JN |
451 | irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? |
452 | IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING; | |
ff77c352 | 453 | if (test_bit(FLAG_TRIG_RISE, &gpio_flags)) |
07697461 JN |
454 | irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? |
455 | IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING; | |
ff77c352 | 456 | |
5ba1821d | 457 | if (!value_sd) { |
388975cc | 458 | value_sd = sysfs_get_dirent(dev->kobj.sd, "value"); |
5ba1821d DG |
459 | if (!value_sd) { |
460 | ret = -ENODEV; | |
ff77c352 DG |
461 | goto err_out; |
462 | } | |
463 | ||
62f516b8 TH |
464 | ret = idr_alloc(&dirent_idr, value_sd, 1, 0, GFP_KERNEL); |
465 | if (ret < 0) | |
5ba1821d | 466 | goto free_sd; |
62f516b8 | 467 | id = ret; |
ff77c352 DG |
468 | |
469 | desc->flags &= GPIO_FLAGS_MASK; | |
5ba1821d | 470 | desc->flags |= (unsigned long)id << ID_SHIFT; |
ff77c352 | 471 | |
5ba1821d | 472 | if (desc->flags >> ID_SHIFT != id) { |
ff77c352 DG |
473 | ret = -ERANGE; |
474 | goto free_id; | |
475 | } | |
ff77c352 DG |
476 | } |
477 | ||
364fadb3 | 478 | ret = request_any_context_irq(irq, gpio_sysfs_irq, irq_flags, |
5ba1821d | 479 | "gpiolib", value_sd); |
364fadb3 | 480 | if (ret < 0) |
5ba1821d | 481 | goto free_id; |
ff77c352 | 482 | |
d468bf9e LW |
483 | ret = gpiod_lock_as_irq(desc); |
484 | if (ret < 0) { | |
485 | gpiod_warn(desc, "failed to flag the GPIO for IRQ\n"); | |
486 | goto free_id; | |
487 | } | |
488 | ||
ff77c352 DG |
489 | desc->flags |= gpio_flags; |
490 | return 0; | |
491 | ||
ff77c352 | 492 | free_id: |
5ba1821d | 493 | idr_remove(&dirent_idr, id); |
ff77c352 | 494 | desc->flags &= GPIO_FLAGS_MASK; |
5ba1821d DG |
495 | free_sd: |
496 | if (value_sd) | |
497 | sysfs_put(value_sd); | |
ff77c352 DG |
498 | err_out: |
499 | return ret; | |
500 | } | |
501 | ||
502 | static const struct { | |
503 | const char *name; | |
504 | unsigned long flags; | |
505 | } trigger_types[] = { | |
506 | { "none", 0 }, | |
507 | { "falling", BIT(FLAG_TRIG_FALL) }, | |
508 | { "rising", BIT(FLAG_TRIG_RISE) }, | |
509 | { "both", BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE) }, | |
510 | }; | |
511 | ||
512 | static ssize_t gpio_edge_show(struct device *dev, | |
513 | struct device_attribute *attr, char *buf) | |
514 | { | |
515 | const struct gpio_desc *desc = dev_get_drvdata(dev); | |
516 | ssize_t status; | |
517 | ||
518 | mutex_lock(&sysfs_lock); | |
519 | ||
520 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
521 | status = -EIO; | |
522 | else { | |
523 | int i; | |
524 | ||
525 | status = 0; | |
526 | for (i = 0; i < ARRAY_SIZE(trigger_types); i++) | |
527 | if ((desc->flags & GPIO_TRIGGER_MASK) | |
528 | == trigger_types[i].flags) { | |
529 | status = sprintf(buf, "%s\n", | |
530 | trigger_types[i].name); | |
531 | break; | |
532 | } | |
533 | } | |
534 | ||
535 | mutex_unlock(&sysfs_lock); | |
536 | return status; | |
537 | } | |
538 | ||
539 | static ssize_t gpio_edge_store(struct device *dev, | |
540 | struct device_attribute *attr, const char *buf, size_t size) | |
541 | { | |
542 | struct gpio_desc *desc = dev_get_drvdata(dev); | |
543 | ssize_t status; | |
544 | int i; | |
545 | ||
546 | for (i = 0; i < ARRAY_SIZE(trigger_types); i++) | |
547 | if (sysfs_streq(trigger_types[i].name, buf)) | |
548 | goto found; | |
549 | return -EINVAL; | |
550 | ||
551 | found: | |
552 | mutex_lock(&sysfs_lock); | |
553 | ||
554 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
555 | status = -EIO; | |
556 | else { | |
557 | status = gpio_setup_irq(desc, dev, trigger_types[i].flags); | |
558 | if (!status) | |
559 | status = size; | |
560 | } | |
561 | ||
562 | mutex_unlock(&sysfs_lock); | |
563 | ||
564 | return status; | |
565 | } | |
566 | ||
567 | static DEVICE_ATTR(edge, 0644, gpio_edge_show, gpio_edge_store); | |
568 | ||
07697461 JN |
569 | static int sysfs_set_active_low(struct gpio_desc *desc, struct device *dev, |
570 | int value) | |
571 | { | |
572 | int status = 0; | |
573 | ||
574 | if (!!test_bit(FLAG_ACTIVE_LOW, &desc->flags) == !!value) | |
575 | return 0; | |
576 | ||
577 | if (value) | |
578 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
579 | else | |
580 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
581 | ||
582 | /* reconfigure poll(2) support if enabled on one edge only */ | |
583 | if (dev != NULL && (!!test_bit(FLAG_TRIG_RISE, &desc->flags) ^ | |
584 | !!test_bit(FLAG_TRIG_FALL, &desc->flags))) { | |
585 | unsigned long trigger_flags = desc->flags & GPIO_TRIGGER_MASK; | |
586 | ||
587 | gpio_setup_irq(desc, dev, 0); | |
588 | status = gpio_setup_irq(desc, dev, trigger_flags); | |
589 | } | |
590 | ||
591 | return status; | |
592 | } | |
593 | ||
594 | static ssize_t gpio_active_low_show(struct device *dev, | |
595 | struct device_attribute *attr, char *buf) | |
596 | { | |
597 | const struct gpio_desc *desc = dev_get_drvdata(dev); | |
598 | ssize_t status; | |
599 | ||
600 | mutex_lock(&sysfs_lock); | |
601 | ||
602 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
603 | status = -EIO; | |
604 | else | |
605 | status = sprintf(buf, "%d\n", | |
606 | !!test_bit(FLAG_ACTIVE_LOW, &desc->flags)); | |
607 | ||
608 | mutex_unlock(&sysfs_lock); | |
609 | ||
610 | return status; | |
611 | } | |
612 | ||
613 | static ssize_t gpio_active_low_store(struct device *dev, | |
614 | struct device_attribute *attr, const char *buf, size_t size) | |
615 | { | |
616 | struct gpio_desc *desc = dev_get_drvdata(dev); | |
617 | ssize_t status; | |
618 | ||
619 | mutex_lock(&sysfs_lock); | |
620 | ||
621 | if (!test_bit(FLAG_EXPORT, &desc->flags)) { | |
622 | status = -EIO; | |
623 | } else { | |
624 | long value; | |
625 | ||
a3d88c92 | 626 | status = kstrtol(buf, 0, &value); |
07697461 JN |
627 | if (status == 0) |
628 | status = sysfs_set_active_low(desc, dev, value != 0); | |
629 | } | |
630 | ||
631 | mutex_unlock(&sysfs_lock); | |
632 | ||
633 | return status ? : size; | |
634 | } | |
635 | ||
636 | static const DEVICE_ATTR(active_low, 0644, | |
637 | gpio_active_low_show, gpio_active_low_store); | |
638 | ||
d8f388d8 | 639 | static const struct attribute *gpio_attrs[] = { |
d8f388d8 | 640 | &dev_attr_value.attr, |
07697461 | 641 | &dev_attr_active_low.attr, |
d8f388d8 DB |
642 | NULL, |
643 | }; | |
644 | ||
645 | static const struct attribute_group gpio_attr_group = { | |
646 | .attrs = (struct attribute **) gpio_attrs, | |
647 | }; | |
648 | ||
649 | /* | |
650 | * /sys/class/gpio/gpiochipN/ | |
651 | * /base ... matching gpio_chip.base (N) | |
652 | * /label ... matching gpio_chip.label | |
653 | * /ngpio ... matching gpio_chip.ngpio | |
654 | */ | |
655 | ||
656 | static ssize_t chip_base_show(struct device *dev, | |
657 | struct device_attribute *attr, char *buf) | |
658 | { | |
659 | const struct gpio_chip *chip = dev_get_drvdata(dev); | |
660 | ||
661 | return sprintf(buf, "%d\n", chip->base); | |
662 | } | |
663 | static DEVICE_ATTR(base, 0444, chip_base_show, NULL); | |
664 | ||
665 | static ssize_t chip_label_show(struct device *dev, | |
666 | struct device_attribute *attr, char *buf) | |
667 | { | |
668 | const struct gpio_chip *chip = dev_get_drvdata(dev); | |
669 | ||
670 | return sprintf(buf, "%s\n", chip->label ? : ""); | |
671 | } | |
672 | static DEVICE_ATTR(label, 0444, chip_label_show, NULL); | |
673 | ||
674 | static ssize_t chip_ngpio_show(struct device *dev, | |
675 | struct device_attribute *attr, char *buf) | |
676 | { | |
677 | const struct gpio_chip *chip = dev_get_drvdata(dev); | |
678 | ||
679 | return sprintf(buf, "%u\n", chip->ngpio); | |
680 | } | |
681 | static DEVICE_ATTR(ngpio, 0444, chip_ngpio_show, NULL); | |
682 | ||
683 | static const struct attribute *gpiochip_attrs[] = { | |
684 | &dev_attr_base.attr, | |
685 | &dev_attr_label.attr, | |
686 | &dev_attr_ngpio.attr, | |
687 | NULL, | |
688 | }; | |
689 | ||
690 | static const struct attribute_group gpiochip_attr_group = { | |
691 | .attrs = (struct attribute **) gpiochip_attrs, | |
692 | }; | |
693 | ||
694 | /* | |
695 | * /sys/class/gpio/export ... write-only | |
696 | * integer N ... number of GPIO to export (full access) | |
697 | * /sys/class/gpio/unexport ... write-only | |
698 | * integer N ... number of GPIO to unexport | |
699 | */ | |
28812fe1 AK |
700 | static ssize_t export_store(struct class *class, |
701 | struct class_attribute *attr, | |
702 | const char *buf, size_t len) | |
d8f388d8 | 703 | { |
372e722e AC |
704 | long gpio; |
705 | struct gpio_desc *desc; | |
706 | int status; | |
d8f388d8 | 707 | |
a3d88c92 | 708 | status = kstrtol(buf, 0, &gpio); |
d8f388d8 DB |
709 | if (status < 0) |
710 | goto done; | |
711 | ||
372e722e | 712 | desc = gpio_to_desc(gpio); |
bcabdef1 AC |
713 | /* reject invalid GPIOs */ |
714 | if (!desc) { | |
715 | pr_warn("%s: invalid GPIO %ld\n", __func__, gpio); | |
716 | return -EINVAL; | |
717 | } | |
372e722e | 718 | |
d8f388d8 DB |
719 | /* No extra locking here; FLAG_SYSFS just signifies that the |
720 | * request and export were done by on behalf of userspace, so | |
721 | * they may be undone on its behalf too. | |
722 | */ | |
723 | ||
372e722e | 724 | status = gpiod_request(desc, "sysfs"); |
ad2fab36 MN |
725 | if (status < 0) { |
726 | if (status == -EPROBE_DEFER) | |
727 | status = -ENODEV; | |
d8f388d8 | 728 | goto done; |
ad2fab36 | 729 | } |
372e722e | 730 | status = gpiod_export(desc, true); |
d8f388d8 | 731 | if (status < 0) |
372e722e | 732 | gpiod_free(desc); |
d8f388d8 | 733 | else |
372e722e | 734 | set_bit(FLAG_SYSFS, &desc->flags); |
d8f388d8 DB |
735 | |
736 | done: | |
737 | if (status) | |
738 | pr_debug("%s: status %d\n", __func__, status); | |
739 | return status ? : len; | |
740 | } | |
741 | ||
28812fe1 AK |
742 | static ssize_t unexport_store(struct class *class, |
743 | struct class_attribute *attr, | |
744 | const char *buf, size_t len) | |
d8f388d8 | 745 | { |
372e722e AC |
746 | long gpio; |
747 | struct gpio_desc *desc; | |
748 | int status; | |
d8f388d8 | 749 | |
a3d88c92 | 750 | status = kstrtol(buf, 0, &gpio); |
d8f388d8 DB |
751 | if (status < 0) |
752 | goto done; | |
753 | ||
372e722e | 754 | desc = gpio_to_desc(gpio); |
d8f388d8 | 755 | /* reject bogus commands (gpio_unexport ignores them) */ |
bcabdef1 AC |
756 | if (!desc) { |
757 | pr_warn("%s: invalid GPIO %ld\n", __func__, gpio); | |
758 | return -EINVAL; | |
759 | } | |
760 | ||
761 | status = -EINVAL; | |
d8f388d8 DB |
762 | |
763 | /* No extra locking here; FLAG_SYSFS just signifies that the | |
764 | * request and export were done by on behalf of userspace, so | |
765 | * they may be undone on its behalf too. | |
766 | */ | |
372e722e | 767 | if (test_and_clear_bit(FLAG_SYSFS, &desc->flags)) { |
d8f388d8 | 768 | status = 0; |
372e722e | 769 | gpiod_free(desc); |
d8f388d8 DB |
770 | } |
771 | done: | |
772 | if (status) | |
773 | pr_debug("%s: status %d\n", __func__, status); | |
774 | return status ? : len; | |
775 | } | |
776 | ||
777 | static struct class_attribute gpio_class_attrs[] = { | |
778 | __ATTR(export, 0200, NULL, export_store), | |
779 | __ATTR(unexport, 0200, NULL, unexport_store), | |
780 | __ATTR_NULL, | |
781 | }; | |
782 | ||
783 | static struct class gpio_class = { | |
784 | .name = "gpio", | |
785 | .owner = THIS_MODULE, | |
786 | ||
787 | .class_attrs = gpio_class_attrs, | |
788 | }; | |
789 | ||
790 | ||
791 | /** | |
79a9becd | 792 | * gpiod_export - export a GPIO through sysfs |
d8f388d8 DB |
793 | * @gpio: gpio to make available, already requested |
794 | * @direction_may_change: true if userspace may change gpio direction | |
795 | * Context: arch_initcall or later | |
796 | * | |
797 | * When drivers want to make a GPIO accessible to userspace after they | |
798 | * have requested it -- perhaps while debugging, or as part of their | |
799 | * public interface -- they may use this routine. If the GPIO can | |
800 | * change direction (some can't) and the caller allows it, userspace | |
801 | * will see "direction" sysfs attribute which may be used to change | |
802 | * the gpio's direction. A "value" attribute will always be provided. | |
803 | * | |
804 | * Returns zero on success, else an error. | |
805 | */ | |
79a9becd | 806 | int gpiod_export(struct gpio_desc *desc, bool direction_may_change) |
d8f388d8 DB |
807 | { |
808 | unsigned long flags; | |
fc4e2514 | 809 | int status; |
62154991 | 810 | const char *ioname = NULL; |
fc4e2514 | 811 | struct device *dev; |
372e722e | 812 | int offset; |
d8f388d8 DB |
813 | |
814 | /* can't export until sysfs is available ... */ | |
815 | if (!gpio_class.p) { | |
816 | pr_debug("%s: called too early!\n", __func__); | |
817 | return -ENOENT; | |
818 | } | |
819 | ||
372e722e AC |
820 | if (!desc) { |
821 | pr_debug("%s: invalid gpio descriptor\n", __func__); | |
fc4e2514 RM |
822 | return -EINVAL; |
823 | } | |
d8f388d8 DB |
824 | |
825 | mutex_lock(&sysfs_lock); | |
826 | ||
827 | spin_lock_irqsave(&gpio_lock, flags); | |
fc4e2514 RM |
828 | if (!test_bit(FLAG_REQUESTED, &desc->flags) || |
829 | test_bit(FLAG_EXPORT, &desc->flags)) { | |
830 | spin_unlock_irqrestore(&gpio_lock, flags); | |
7589e59f AS |
831 | gpiod_dbg(desc, "%s: unavailable (requested=%d, exported=%d)\n", |
832 | __func__, | |
fc4e2514 RM |
833 | test_bit(FLAG_REQUESTED, &desc->flags), |
834 | test_bit(FLAG_EXPORT, &desc->flags)); | |
529f2ad5 DC |
835 | status = -EPERM; |
836 | goto fail_unlock; | |
d8f388d8 | 837 | } |
fc4e2514 RM |
838 | |
839 | if (!desc->chip->direction_input || !desc->chip->direction_output) | |
840 | direction_may_change = false; | |
d8f388d8 DB |
841 | spin_unlock_irqrestore(&gpio_lock, flags); |
842 | ||
372e722e AC |
843 | offset = gpio_chip_hwgpio(desc); |
844 | if (desc->chip->names && desc->chip->names[offset]) | |
845 | ioname = desc->chip->names[offset]; | |
926b663c | 846 | |
fc4e2514 | 847 | dev = device_create(&gpio_class, desc->chip->dev, MKDEV(0, 0), |
372e722e AC |
848 | desc, ioname ? ioname : "gpio%u", |
849 | desc_to_gpio(desc)); | |
fc4e2514 RM |
850 | if (IS_ERR(dev)) { |
851 | status = PTR_ERR(dev); | |
852 | goto fail_unlock; | |
d8f388d8 DB |
853 | } |
854 | ||
fc4e2514 | 855 | status = sysfs_create_group(&dev->kobj, &gpio_attr_group); |
d8f388d8 | 856 | if (status) |
fc4e2514 | 857 | goto fail_unregister_device; |
d8f388d8 | 858 | |
fc4e2514 RM |
859 | if (direction_may_change) { |
860 | status = device_create_file(dev, &dev_attr_direction); | |
861 | if (status) | |
862 | goto fail_unregister_device; | |
863 | } | |
864 | ||
372e722e | 865 | if (gpiod_to_irq(desc) >= 0 && (direction_may_change || |
fc4e2514 RM |
866 | !test_bit(FLAG_IS_OUT, &desc->flags))) { |
867 | status = device_create_file(dev, &dev_attr_edge); | |
868 | if (status) | |
869 | goto fail_unregister_device; | |
870 | } | |
d8f388d8 | 871 | |
fc4e2514 RM |
872 | set_bit(FLAG_EXPORT, &desc->flags); |
873 | mutex_unlock(&sysfs_lock); | |
874 | return 0; | |
875 | ||
876 | fail_unregister_device: | |
877 | device_unregister(dev); | |
878 | fail_unlock: | |
879 | mutex_unlock(&sysfs_lock); | |
7589e59f | 880 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
d8f388d8 DB |
881 | return status; |
882 | } | |
79a9becd | 883 | EXPORT_SYMBOL_GPL(gpiod_export); |
d8f388d8 | 884 | |
9f3b795a | 885 | static int match_export(struct device *dev, const void *data) |
d8f388d8 DB |
886 | { |
887 | return dev_get_drvdata(dev) == data; | |
888 | } | |
889 | ||
a4177ee7 | 890 | /** |
79a9becd | 891 | * gpiod_export_link - create a sysfs link to an exported GPIO node |
a4177ee7 JN |
892 | * @dev: device under which to create symlink |
893 | * @name: name of the symlink | |
894 | * @gpio: gpio to create symlink to, already exported | |
895 | * | |
896 | * Set up a symlink from /sys/.../dev/name to /sys/class/gpio/gpioN | |
897 | * node. Caller is responsible for unlinking. | |
898 | * | |
899 | * Returns zero on success, else an error. | |
900 | */ | |
79a9becd AC |
901 | int gpiod_export_link(struct device *dev, const char *name, |
902 | struct gpio_desc *desc) | |
a4177ee7 | 903 | { |
a4177ee7 JN |
904 | int status = -EINVAL; |
905 | ||
bcabdef1 AC |
906 | if (!desc) { |
907 | pr_warn("%s: invalid GPIO\n", __func__); | |
908 | return -EINVAL; | |
909 | } | |
a4177ee7 JN |
910 | |
911 | mutex_lock(&sysfs_lock); | |
912 | ||
a4177ee7 JN |
913 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
914 | struct device *tdev; | |
915 | ||
916 | tdev = class_find_device(&gpio_class, NULL, desc, match_export); | |
917 | if (tdev != NULL) { | |
918 | status = sysfs_create_link(&dev->kobj, &tdev->kobj, | |
919 | name); | |
920 | } else { | |
921 | status = -ENODEV; | |
922 | } | |
923 | } | |
924 | ||
925 | mutex_unlock(&sysfs_lock); | |
926 | ||
a4177ee7 | 927 | if (status) |
7589e59f | 928 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
a4177ee7 JN |
929 | |
930 | return status; | |
931 | } | |
79a9becd | 932 | EXPORT_SYMBOL_GPL(gpiod_export_link); |
07697461 JN |
933 | |
934 | /** | |
79a9becd | 935 | * gpiod_sysfs_set_active_low - set the polarity of gpio sysfs value |
07697461 JN |
936 | * @gpio: gpio to change |
937 | * @value: non-zero to use active low, i.e. inverted values | |
938 | * | |
939 | * Set the polarity of /sys/class/gpio/gpioN/value sysfs attribute. | |
940 | * The GPIO does not have to be exported yet. If poll(2) support has | |
941 | * been enabled for either rising or falling edge, it will be | |
942 | * reconfigured to follow the new polarity. | |
943 | * | |
944 | * Returns zero on success, else an error. | |
945 | */ | |
79a9becd | 946 | int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value) |
07697461 | 947 | { |
07697461 JN |
948 | struct device *dev = NULL; |
949 | int status = -EINVAL; | |
950 | ||
bcabdef1 AC |
951 | if (!desc) { |
952 | pr_warn("%s: invalid GPIO\n", __func__); | |
953 | return -EINVAL; | |
954 | } | |
07697461 JN |
955 | |
956 | mutex_lock(&sysfs_lock); | |
957 | ||
07697461 | 958 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
07697461 JN |
959 | dev = class_find_device(&gpio_class, NULL, desc, match_export); |
960 | if (dev == NULL) { | |
961 | status = -ENODEV; | |
962 | goto unlock; | |
963 | } | |
964 | } | |
965 | ||
966 | status = sysfs_set_active_low(desc, dev, value); | |
967 | ||
968 | unlock: | |
969 | mutex_unlock(&sysfs_lock); | |
970 | ||
07697461 | 971 | if (status) |
7589e59f | 972 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
07697461 JN |
973 | |
974 | return status; | |
975 | } | |
79a9becd | 976 | EXPORT_SYMBOL_GPL(gpiod_sysfs_set_active_low); |
07697461 | 977 | |
d8f388d8 | 978 | /** |
79a9becd | 979 | * gpiod_unexport - reverse effect of gpio_export() |
d8f388d8 DB |
980 | * @gpio: gpio to make unavailable |
981 | * | |
982 | * This is implicit on gpio_free(). | |
983 | */ | |
79a9becd | 984 | void gpiod_unexport(struct gpio_desc *desc) |
d8f388d8 | 985 | { |
6a99ad4a | 986 | int status = 0; |
864533ce | 987 | struct device *dev = NULL; |
d8f388d8 | 988 | |
372e722e | 989 | if (!desc) { |
bcabdef1 AC |
990 | pr_warn("%s: invalid GPIO\n", __func__); |
991 | return; | |
6a99ad4a | 992 | } |
d8f388d8 DB |
993 | |
994 | mutex_lock(&sysfs_lock); | |
995 | ||
d8f388d8 | 996 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
d8f388d8 DB |
997 | |
998 | dev = class_find_device(&gpio_class, NULL, desc, match_export); | |
999 | if (dev) { | |
ff77c352 | 1000 | gpio_setup_irq(desc, dev, 0); |
d8f388d8 | 1001 | clear_bit(FLAG_EXPORT, &desc->flags); |
d8f388d8 DB |
1002 | } else |
1003 | status = -ENODEV; | |
1004 | } | |
1005 | ||
1006 | mutex_unlock(&sysfs_lock); | |
372e722e | 1007 | |
864533ce ML |
1008 | if (dev) { |
1009 | device_unregister(dev); | |
1010 | put_device(dev); | |
1011 | } | |
bcabdef1 | 1012 | |
d8f388d8 | 1013 | if (status) |
7589e59f | 1014 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
372e722e | 1015 | } |
79a9becd | 1016 | EXPORT_SYMBOL_GPL(gpiod_unexport); |
d8f388d8 DB |
1017 | |
1018 | static int gpiochip_export(struct gpio_chip *chip) | |
1019 | { | |
1020 | int status; | |
1021 | struct device *dev; | |
1022 | ||
1023 | /* Many systems register gpio chips for SOC support very early, | |
1024 | * before driver model support is available. In those cases we | |
1025 | * export this later, in gpiolib_sysfs_init() ... here we just | |
1026 | * verify that _some_ field of gpio_class got initialized. | |
1027 | */ | |
1028 | if (!gpio_class.p) | |
1029 | return 0; | |
1030 | ||
1031 | /* use chip->base for the ID; it's already known to be unique */ | |
1032 | mutex_lock(&sysfs_lock); | |
1033 | dev = device_create(&gpio_class, chip->dev, MKDEV(0, 0), chip, | |
1034 | "gpiochip%d", chip->base); | |
d62668e1 | 1035 | if (!IS_ERR(dev)) { |
d8f388d8 DB |
1036 | status = sysfs_create_group(&dev->kobj, |
1037 | &gpiochip_attr_group); | |
1038 | } else | |
d62668e1 | 1039 | status = PTR_ERR(dev); |
d8f388d8 DB |
1040 | chip->exported = (status == 0); |
1041 | mutex_unlock(&sysfs_lock); | |
1042 | ||
1043 | if (status) { | |
1044 | unsigned long flags; | |
1045 | unsigned gpio; | |
1046 | ||
1047 | spin_lock_irqsave(&gpio_lock, flags); | |
6c0b4e6c AC |
1048 | gpio = 0; |
1049 | while (gpio < chip->ngpio) | |
1050 | chip->desc[gpio++].chip = NULL; | |
d8f388d8 DB |
1051 | spin_unlock_irqrestore(&gpio_lock, flags); |
1052 | ||
1a2a99c6 | 1053 | chip_dbg(chip, "%s: status %d\n", __func__, status); |
d8f388d8 DB |
1054 | } |
1055 | ||
1056 | return status; | |
1057 | } | |
1058 | ||
1059 | static void gpiochip_unexport(struct gpio_chip *chip) | |
1060 | { | |
1061 | int status; | |
1062 | struct device *dev; | |
1063 | ||
1064 | mutex_lock(&sysfs_lock); | |
1065 | dev = class_find_device(&gpio_class, NULL, chip, match_export); | |
1066 | if (dev) { | |
1067 | put_device(dev); | |
1068 | device_unregister(dev); | |
9fb1f39e | 1069 | chip->exported = false; |
d8f388d8 DB |
1070 | status = 0; |
1071 | } else | |
1072 | status = -ENODEV; | |
1073 | mutex_unlock(&sysfs_lock); | |
1074 | ||
1075 | if (status) | |
1a2a99c6 | 1076 | chip_dbg(chip, "%s: status %d\n", __func__, status); |
d8f388d8 DB |
1077 | } |
1078 | ||
1079 | static int __init gpiolib_sysfs_init(void) | |
1080 | { | |
1081 | int status; | |
1082 | unsigned long flags; | |
65493e3a | 1083 | struct gpio_chip *chip; |
d8f388d8 DB |
1084 | |
1085 | status = class_register(&gpio_class); | |
1086 | if (status < 0) | |
1087 | return status; | |
1088 | ||
1089 | /* Scan and register the gpio_chips which registered very | |
1090 | * early (e.g. before the class_register above was called). | |
1091 | * | |
1092 | * We run before arch_initcall() so chip->dev nodes can have | |
1093 | * registered, and so arch_initcall() can always gpio_export(). | |
1094 | */ | |
1095 | spin_lock_irqsave(&gpio_lock, flags); | |
65493e3a | 1096 | list_for_each_entry(chip, &gpio_chips, list) { |
d8f388d8 DB |
1097 | if (!chip || chip->exported) |
1098 | continue; | |
1099 | ||
1100 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1101 | status = gpiochip_export(chip); | |
1102 | spin_lock_irqsave(&gpio_lock, flags); | |
1103 | } | |
1104 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1105 | ||
1106 | ||
1107 | return status; | |
1108 | } | |
1109 | postcore_initcall(gpiolib_sysfs_init); | |
1110 | ||
1111 | #else | |
1112 | static inline int gpiochip_export(struct gpio_chip *chip) | |
1113 | { | |
1114 | return 0; | |
1115 | } | |
1116 | ||
1117 | static inline void gpiochip_unexport(struct gpio_chip *chip) | |
1118 | { | |
1119 | } | |
1120 | ||
1121 | #endif /* CONFIG_GPIO_SYSFS */ | |
1122 | ||
1a989d0f AC |
1123 | /* |
1124 | * Add a new chip to the global chips list, keeping the list of chips sorted | |
1125 | * by base order. | |
1126 | * | |
1127 | * Return -EBUSY if the new chip overlaps with some other chip's integer | |
1128 | * space. | |
1129 | */ | |
1130 | static int gpiochip_add_to_list(struct gpio_chip *chip) | |
1131 | { | |
1132 | struct list_head *pos = &gpio_chips; | |
1133 | struct gpio_chip *_chip; | |
1134 | int err = 0; | |
1135 | ||
1136 | /* find where to insert our chip */ | |
1137 | list_for_each(pos, &gpio_chips) { | |
1138 | _chip = list_entry(pos, struct gpio_chip, list); | |
1139 | /* shall we insert before _chip? */ | |
1140 | if (_chip->base >= chip->base + chip->ngpio) | |
1141 | break; | |
1142 | } | |
1143 | ||
1144 | /* are we stepping on the chip right before? */ | |
1145 | if (pos != &gpio_chips && pos->prev != &gpio_chips) { | |
1146 | _chip = list_entry(pos->prev, struct gpio_chip, list); | |
1147 | if (_chip->base + _chip->ngpio > chip->base) { | |
1148 | dev_err(chip->dev, | |
1149 | "GPIO integer space overlap, cannot add chip\n"); | |
1150 | err = -EBUSY; | |
1151 | } | |
1152 | } | |
1153 | ||
1154 | if (!err) | |
1155 | list_add_tail(&chip->list, pos); | |
1156 | ||
1157 | return err; | |
1158 | } | |
1159 | ||
d2876d08 DB |
1160 | /** |
1161 | * gpiochip_add() - register a gpio_chip | |
1162 | * @chip: the chip to register, with chip->base initialized | |
1163 | * Context: potentially before irqs or kmalloc will work | |
1164 | * | |
1165 | * Returns a negative errno if the chip can't be registered, such as | |
1166 | * because the chip->base is invalid or already associated with a | |
1167 | * different chip. Otherwise it returns zero as a success code. | |
8d0aab2f | 1168 | * |
d8f388d8 DB |
1169 | * When gpiochip_add() is called very early during boot, so that GPIOs |
1170 | * can be freely used, the chip->dev device must be registered before | |
1171 | * the gpio framework's arch_initcall(). Otherwise sysfs initialization | |
1172 | * for GPIOs will fail rudely. | |
1173 | * | |
8d0aab2f AV |
1174 | * If chip->base is negative, this requests dynamic assignment of |
1175 | * a range of valid GPIOs. | |
d2876d08 DB |
1176 | */ |
1177 | int gpiochip_add(struct gpio_chip *chip) | |
1178 | { | |
1179 | unsigned long flags; | |
1180 | int status = 0; | |
1181 | unsigned id; | |
8d0aab2f | 1182 | int base = chip->base; |
d2876d08 | 1183 | |
bff5fda9 | 1184 | if ((!gpio_is_valid(base) || !gpio_is_valid(base + chip->ngpio - 1)) |
8d0aab2f | 1185 | && base >= 0) { |
d2876d08 DB |
1186 | status = -EINVAL; |
1187 | goto fail; | |
1188 | } | |
1189 | ||
1190 | spin_lock_irqsave(&gpio_lock, flags); | |
1191 | ||
8d0aab2f AV |
1192 | if (base < 0) { |
1193 | base = gpiochip_find_base(chip->ngpio); | |
1194 | if (base < 0) { | |
1195 | status = base; | |
d8f388d8 | 1196 | goto unlock; |
8d0aab2f AV |
1197 | } |
1198 | chip->base = base; | |
1199 | } | |
1200 | ||
1a989d0f AC |
1201 | status = gpiochip_add_to_list(chip); |
1202 | ||
d2876d08 | 1203 | if (status == 0) { |
6c0b4e6c AC |
1204 | chip->desc = &gpio_desc[chip->base]; |
1205 | ||
1206 | for (id = 0; id < chip->ngpio; id++) { | |
1207 | struct gpio_desc *desc = &chip->desc[id]; | |
1208 | desc->chip = chip; | |
d8f388d8 DB |
1209 | |
1210 | /* REVISIT: most hardware initializes GPIOs as | |
1211 | * inputs (often with pullups enabled) so power | |
1212 | * usage is minimized. Linux code should set the | |
1213 | * gpio direction first thing; but until it does, | |
80b0a602 | 1214 | * and in case chip->get_direction is not set, |
d8f388d8 DB |
1215 | * we may expose the wrong direction in sysfs. |
1216 | */ | |
6c0b4e6c | 1217 | desc->flags = !chip->direction_input |
d8f388d8 DB |
1218 | ? (1 << FLAG_IS_OUT) |
1219 | : 0; | |
d2876d08 DB |
1220 | } |
1221 | } | |
1222 | ||
3bae4811 ZG |
1223 | spin_unlock_irqrestore(&gpio_lock, flags); |
1224 | ||
f23f1516 SH |
1225 | #ifdef CONFIG_PINCTRL |
1226 | INIT_LIST_HEAD(&chip->pin_ranges); | |
1227 | #endif | |
1228 | ||
391c970c | 1229 | of_gpiochip_add(chip); |
664e3e5a | 1230 | acpi_gpiochip_add(chip); |
391c970c | 1231 | |
cedb1881 AV |
1232 | if (status) |
1233 | goto fail; | |
1234 | ||
1235 | status = gpiochip_export(chip); | |
1236 | if (status) | |
1237 | goto fail; | |
1238 | ||
7589e59f | 1239 | pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__, |
64842aad GL |
1240 | chip->base, chip->base + chip->ngpio - 1, |
1241 | chip->label ? : "generic"); | |
1242 | ||
cedb1881 | 1243 | return 0; |
3bae4811 ZG |
1244 | |
1245 | unlock: | |
1246 | spin_unlock_irqrestore(&gpio_lock, flags); | |
d2876d08 DB |
1247 | fail: |
1248 | /* failures here can mean systems won't boot... */ | |
7589e59f | 1249 | pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__, |
cedb1881 AV |
1250 | chip->base, chip->base + chip->ngpio - 1, |
1251 | chip->label ? : "generic"); | |
d2876d08 DB |
1252 | return status; |
1253 | } | |
1254 | EXPORT_SYMBOL_GPL(gpiochip_add); | |
1255 | ||
1256 | /** | |
1257 | * gpiochip_remove() - unregister a gpio_chip | |
1258 | * @chip: the chip to unregister | |
1259 | * | |
1260 | * A gpio_chip with any GPIOs still requested may not be removed. | |
1261 | */ | |
1262 | int gpiochip_remove(struct gpio_chip *chip) | |
1263 | { | |
1264 | unsigned long flags; | |
1265 | int status = 0; | |
1266 | unsigned id; | |
1267 | ||
1268 | spin_lock_irqsave(&gpio_lock, flags); | |
1269 | ||
9ef0d6f7 | 1270 | gpiochip_remove_pin_ranges(chip); |
391c970c | 1271 | of_gpiochip_remove(chip); |
664e3e5a | 1272 | acpi_gpiochip_remove(chip); |
391c970c | 1273 | |
6c0b4e6c AC |
1274 | for (id = 0; id < chip->ngpio; id++) { |
1275 | if (test_bit(FLAG_REQUESTED, &chip->desc[id].flags)) { | |
d2876d08 DB |
1276 | status = -EBUSY; |
1277 | break; | |
1278 | } | |
1279 | } | |
1280 | if (status == 0) { | |
6c0b4e6c AC |
1281 | for (id = 0; id < chip->ngpio; id++) |
1282 | chip->desc[id].chip = NULL; | |
1a989d0f AC |
1283 | |
1284 | list_del(&chip->list); | |
d2876d08 DB |
1285 | } |
1286 | ||
1287 | spin_unlock_irqrestore(&gpio_lock, flags); | |
d8f388d8 DB |
1288 | |
1289 | if (status == 0) | |
1290 | gpiochip_unexport(chip); | |
1291 | ||
d2876d08 DB |
1292 | return status; |
1293 | } | |
1294 | EXPORT_SYMBOL_GPL(gpiochip_remove); | |
1295 | ||
594fa265 GL |
1296 | /** |
1297 | * gpiochip_find() - iterator for locating a specific gpio_chip | |
1298 | * @data: data to pass to match function | |
1299 | * @callback: Callback function to check gpio_chip | |
1300 | * | |
1301 | * Similar to bus_find_device. It returns a reference to a gpio_chip as | |
1302 | * determined by a user supplied @match callback. The callback should return | |
1303 | * 0 if the device doesn't match and non-zero if it does. If the callback is | |
1304 | * non-zero, this function will return to the caller and not iterate over any | |
1305 | * more gpio_chips. | |
1306 | */ | |
07ce8ec7 | 1307 | struct gpio_chip *gpiochip_find(void *data, |
6e2cf651 | 1308 | int (*match)(struct gpio_chip *chip, |
3d0f7cf0 | 1309 | void *data)) |
594fa265 | 1310 | { |
125eef96 | 1311 | struct gpio_chip *chip; |
594fa265 | 1312 | unsigned long flags; |
594fa265 GL |
1313 | |
1314 | spin_lock_irqsave(&gpio_lock, flags); | |
125eef96 AC |
1315 | list_for_each_entry(chip, &gpio_chips, list) |
1316 | if (match(chip, data)) | |
594fa265 | 1317 | break; |
125eef96 AC |
1318 | |
1319 | /* No match? */ | |
1320 | if (&chip->list == &gpio_chips) | |
1321 | chip = NULL; | |
594fa265 GL |
1322 | spin_unlock_irqrestore(&gpio_lock, flags); |
1323 | ||
1324 | return chip; | |
1325 | } | |
8fa0c9bf | 1326 | EXPORT_SYMBOL_GPL(gpiochip_find); |
d2876d08 | 1327 | |
79697ef9 AC |
1328 | static int gpiochip_match_name(struct gpio_chip *chip, void *data) |
1329 | { | |
1330 | const char *name = data; | |
1331 | ||
1332 | return !strcmp(chip->label, name); | |
1333 | } | |
1334 | ||
1335 | static struct gpio_chip *find_chip_by_name(const char *name) | |
1336 | { | |
1337 | return gpiochip_find((void *)name, gpiochip_match_name); | |
1338 | } | |
1339 | ||
f23f1516 | 1340 | #ifdef CONFIG_PINCTRL |
165adc9c | 1341 | |
586a87e6 CR |
1342 | /** |
1343 | * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping | |
1344 | * @chip: the gpiochip to add the range for | |
1345 | * @pinctrl: the dev_name() of the pin controller to map to | |
1346 | * @gpio_offset: the start offset in the current gpio_chip number space | |
1347 | * @pin_group: name of the pin group inside the pin controller | |
1348 | */ | |
1349 | int gpiochip_add_pingroup_range(struct gpio_chip *chip, | |
1350 | struct pinctrl_dev *pctldev, | |
1351 | unsigned int gpio_offset, const char *pin_group) | |
1352 | { | |
1353 | struct gpio_pin_range *pin_range; | |
1354 | int ret; | |
1355 | ||
1356 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); | |
1357 | if (!pin_range) { | |
1a2a99c6 | 1358 | chip_err(chip, "failed to allocate pin ranges\n"); |
586a87e6 CR |
1359 | return -ENOMEM; |
1360 | } | |
1361 | ||
1362 | /* Use local offset as range ID */ | |
1363 | pin_range->range.id = gpio_offset; | |
1364 | pin_range->range.gc = chip; | |
1365 | pin_range->range.name = chip->label; | |
1366 | pin_range->range.base = chip->base + gpio_offset; | |
1367 | pin_range->pctldev = pctldev; | |
1368 | ||
1369 | ret = pinctrl_get_group_pins(pctldev, pin_group, | |
1370 | &pin_range->range.pins, | |
1371 | &pin_range->range.npins); | |
61c6375d MN |
1372 | if (ret < 0) { |
1373 | kfree(pin_range); | |
586a87e6 | 1374 | return ret; |
61c6375d | 1375 | } |
586a87e6 CR |
1376 | |
1377 | pinctrl_add_gpio_range(pctldev, &pin_range->range); | |
1378 | ||
1a2a99c6 AS |
1379 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n", |
1380 | gpio_offset, gpio_offset + pin_range->range.npins - 1, | |
586a87e6 CR |
1381 | pinctrl_dev_get_devname(pctldev), pin_group); |
1382 | ||
1383 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
1384 | ||
1385 | return 0; | |
1386 | } | |
1387 | EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); | |
1388 | ||
3f0f8670 LW |
1389 | /** |
1390 | * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping | |
1391 | * @chip: the gpiochip to add the range for | |
1392 | * @pinctrl_name: the dev_name() of the pin controller to map to | |
316511c0 LW |
1393 | * @gpio_offset: the start offset in the current gpio_chip number space |
1394 | * @pin_offset: the start offset in the pin controller number space | |
3f0f8670 LW |
1395 | * @npins: the number of pins from the offset of each pin space (GPIO and |
1396 | * pin controller) to accumulate in this range | |
1397 | */ | |
1e63d7b9 | 1398 | int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, |
316511c0 | 1399 | unsigned int gpio_offset, unsigned int pin_offset, |
3f0f8670 | 1400 | unsigned int npins) |
f23f1516 SH |
1401 | { |
1402 | struct gpio_pin_range *pin_range; | |
b4d4b1f0 | 1403 | int ret; |
f23f1516 | 1404 | |
3f0f8670 | 1405 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); |
f23f1516 | 1406 | if (!pin_range) { |
1a2a99c6 | 1407 | chip_err(chip, "failed to allocate pin ranges\n"); |
1e63d7b9 | 1408 | return -ENOMEM; |
f23f1516 SH |
1409 | } |
1410 | ||
3f0f8670 | 1411 | /* Use local offset as range ID */ |
316511c0 | 1412 | pin_range->range.id = gpio_offset; |
3f0f8670 | 1413 | pin_range->range.gc = chip; |
f23f1516 | 1414 | pin_range->range.name = chip->label; |
316511c0 LW |
1415 | pin_range->range.base = chip->base + gpio_offset; |
1416 | pin_range->range.pin_base = pin_offset; | |
f23f1516 | 1417 | pin_range->range.npins = npins; |
192c369c | 1418 | pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, |
f23f1516 | 1419 | &pin_range->range); |
8f23ca1a | 1420 | if (IS_ERR(pin_range->pctldev)) { |
b4d4b1f0 | 1421 | ret = PTR_ERR(pin_range->pctldev); |
1a2a99c6 | 1422 | chip_err(chip, "could not create pin range\n"); |
3f0f8670 | 1423 | kfree(pin_range); |
b4d4b1f0 | 1424 | return ret; |
3f0f8670 | 1425 | } |
1a2a99c6 AS |
1426 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n", |
1427 | gpio_offset, gpio_offset + npins - 1, | |
316511c0 LW |
1428 | pinctl_name, |
1429 | pin_offset, pin_offset + npins - 1); | |
f23f1516 SH |
1430 | |
1431 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
1e63d7b9 LW |
1432 | |
1433 | return 0; | |
f23f1516 | 1434 | } |
165adc9c | 1435 | EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); |
f23f1516 | 1436 | |
3f0f8670 LW |
1437 | /** |
1438 | * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings | |
1439 | * @chip: the chip to remove all the mappings for | |
1440 | */ | |
f23f1516 SH |
1441 | void gpiochip_remove_pin_ranges(struct gpio_chip *chip) |
1442 | { | |
1443 | struct gpio_pin_range *pin_range, *tmp; | |
1444 | ||
1445 | list_for_each_entry_safe(pin_range, tmp, &chip->pin_ranges, node) { | |
1446 | list_del(&pin_range->node); | |
1447 | pinctrl_remove_gpio_range(pin_range->pctldev, | |
1448 | &pin_range->range); | |
3f0f8670 | 1449 | kfree(pin_range); |
f23f1516 SH |
1450 | } |
1451 | } | |
165adc9c LW |
1452 | EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); |
1453 | ||
1454 | #endif /* CONFIG_PINCTRL */ | |
f23f1516 | 1455 | |
d2876d08 DB |
1456 | /* These "optional" allocation calls help prevent drivers from stomping |
1457 | * on each other, and help provide better diagnostics in debugfs. | |
1458 | * They're called even less than the "set direction" calls. | |
1459 | */ | |
372e722e | 1460 | static int gpiod_request(struct gpio_desc *desc, const char *label) |
d2876d08 | 1461 | { |
35e8bb51 | 1462 | struct gpio_chip *chip; |
e9354576 | 1463 | int status = -EPROBE_DEFER; |
d2876d08 DB |
1464 | unsigned long flags; |
1465 | ||
0204df47 | 1466 | if (!desc) { |
bcabdef1 AC |
1467 | pr_warn("%s: invalid GPIO\n", __func__); |
1468 | return -EINVAL; | |
ad2fab36 | 1469 | } |
bcabdef1 AC |
1470 | |
1471 | spin_lock_irqsave(&gpio_lock, flags); | |
1472 | ||
35e8bb51 | 1473 | chip = desc->chip; |
0204df47 AC |
1474 | if (chip == NULL) |
1475 | goto done; | |
d2876d08 | 1476 | |
35e8bb51 | 1477 | if (!try_module_get(chip->owner)) |
438d8908 GL |
1478 | goto done; |
1479 | ||
d2876d08 | 1480 | /* NOTE: gpio_request() can be called in early boot, |
35e8bb51 | 1481 | * before IRQs are enabled, for non-sleeping (SOC) GPIOs. |
d2876d08 DB |
1482 | */ |
1483 | ||
1484 | if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { | |
1485 | desc_set_label(desc, label ? : "?"); | |
1486 | status = 0; | |
438d8908 | 1487 | } else { |
d2876d08 | 1488 | status = -EBUSY; |
35e8bb51 | 1489 | module_put(chip->owner); |
7460db56 | 1490 | goto done; |
35e8bb51 DB |
1491 | } |
1492 | ||
1493 | if (chip->request) { | |
1494 | /* chip->request may sleep */ | |
1495 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 1496 | status = chip->request(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
1497 | spin_lock_irqsave(&gpio_lock, flags); |
1498 | ||
1499 | if (status < 0) { | |
1500 | desc_set_label(desc, NULL); | |
1501 | module_put(chip->owner); | |
1502 | clear_bit(FLAG_REQUESTED, &desc->flags); | |
80b0a602 | 1503 | goto done; |
35e8bb51 | 1504 | } |
438d8908 | 1505 | } |
80b0a602 MN |
1506 | if (chip->get_direction) { |
1507 | /* chip->get_direction may sleep */ | |
1508 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 1509 | gpiod_get_direction(desc); |
80b0a602 MN |
1510 | spin_lock_irqsave(&gpio_lock, flags); |
1511 | } | |
d2876d08 DB |
1512 | done: |
1513 | if (status) | |
7589e59f | 1514 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
d2876d08 DB |
1515 | spin_unlock_irqrestore(&gpio_lock, flags); |
1516 | return status; | |
1517 | } | |
372e722e AC |
1518 | |
1519 | int gpio_request(unsigned gpio, const char *label) | |
1520 | { | |
1521 | return gpiod_request(gpio_to_desc(gpio), label); | |
1522 | } | |
d2876d08 DB |
1523 | EXPORT_SYMBOL_GPL(gpio_request); |
1524 | ||
372e722e | 1525 | static void gpiod_free(struct gpio_desc *desc) |
d2876d08 DB |
1526 | { |
1527 | unsigned long flags; | |
35e8bb51 | 1528 | struct gpio_chip *chip; |
d2876d08 | 1529 | |
3d599d1c UKK |
1530 | might_sleep(); |
1531 | ||
372e722e | 1532 | if (!desc) { |
d2876d08 DB |
1533 | WARN_ON(extra_checks); |
1534 | return; | |
1535 | } | |
1536 | ||
372e722e | 1537 | gpiod_unexport(desc); |
d8f388d8 | 1538 | |
d2876d08 DB |
1539 | spin_lock_irqsave(&gpio_lock, flags); |
1540 | ||
35e8bb51 DB |
1541 | chip = desc->chip; |
1542 | if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { | |
1543 | if (chip->free) { | |
1544 | spin_unlock_irqrestore(&gpio_lock, flags); | |
9c4ba946 | 1545 | might_sleep_if(chip->can_sleep); |
372e722e | 1546 | chip->free(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
1547 | spin_lock_irqsave(&gpio_lock, flags); |
1548 | } | |
d2876d08 | 1549 | desc_set_label(desc, NULL); |
438d8908 | 1550 | module_put(desc->chip->owner); |
07697461 | 1551 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); |
35e8bb51 | 1552 | clear_bit(FLAG_REQUESTED, &desc->flags); |
aca5ce14 | 1553 | clear_bit(FLAG_OPEN_DRAIN, &desc->flags); |
25553ff0 | 1554 | clear_bit(FLAG_OPEN_SOURCE, &desc->flags); |
438d8908 | 1555 | } else |
d2876d08 DB |
1556 | WARN_ON(extra_checks); |
1557 | ||
1558 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1559 | } | |
372e722e AC |
1560 | |
1561 | void gpio_free(unsigned gpio) | |
1562 | { | |
1563 | gpiod_free(gpio_to_desc(gpio)); | |
1564 | } | |
d2876d08 DB |
1565 | EXPORT_SYMBOL_GPL(gpio_free); |
1566 | ||
3e45f1d1 EM |
1567 | /** |
1568 | * gpio_request_one - request a single GPIO with initial configuration | |
1569 | * @gpio: the GPIO number | |
1570 | * @flags: GPIO configuration as specified by GPIOF_* | |
1571 | * @label: a literal description string of this GPIO | |
1572 | */ | |
1573 | int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) | |
1574 | { | |
372e722e | 1575 | struct gpio_desc *desc; |
3e45f1d1 EM |
1576 | int err; |
1577 | ||
372e722e AC |
1578 | desc = gpio_to_desc(gpio); |
1579 | ||
1580 | err = gpiod_request(desc, label); | |
3e45f1d1 EM |
1581 | if (err) |
1582 | return err; | |
1583 | ||
aca5ce14 | 1584 | if (flags & GPIOF_OPEN_DRAIN) |
372e722e | 1585 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); |
aca5ce14 | 1586 | |
25553ff0 | 1587 | if (flags & GPIOF_OPEN_SOURCE) |
372e722e | 1588 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); |
25553ff0 | 1589 | |
3e45f1d1 | 1590 | if (flags & GPIOF_DIR_IN) |
372e722e | 1591 | err = gpiod_direction_input(desc); |
3e45f1d1 | 1592 | else |
ef70bbe1 | 1593 | err = gpiod_direction_output_raw(desc, |
3e45f1d1 EM |
1594 | (flags & GPIOF_INIT_HIGH) ? 1 : 0); |
1595 | ||
e254811c | 1596 | if (err) |
fc3a1f04 WS |
1597 | goto free_gpio; |
1598 | ||
1599 | if (flags & GPIOF_EXPORT) { | |
372e722e | 1600 | err = gpiod_export(desc, flags & GPIOF_EXPORT_CHANGEABLE); |
fc3a1f04 WS |
1601 | if (err) |
1602 | goto free_gpio; | |
1603 | } | |
1604 | ||
1605 | return 0; | |
e254811c | 1606 | |
fc3a1f04 | 1607 | free_gpio: |
372e722e | 1608 | gpiod_free(desc); |
3e45f1d1 EM |
1609 | return err; |
1610 | } | |
1611 | EXPORT_SYMBOL_GPL(gpio_request_one); | |
1612 | ||
1613 | /** | |
1614 | * gpio_request_array - request multiple GPIOs in a single call | |
1615 | * @array: array of the 'struct gpio' | |
1616 | * @num: how many GPIOs in the array | |
1617 | */ | |
7c295975 | 1618 | int gpio_request_array(const struct gpio *array, size_t num) |
3e45f1d1 EM |
1619 | { |
1620 | int i, err; | |
1621 | ||
1622 | for (i = 0; i < num; i++, array++) { | |
1623 | err = gpio_request_one(array->gpio, array->flags, array->label); | |
1624 | if (err) | |
1625 | goto err_free; | |
1626 | } | |
1627 | return 0; | |
1628 | ||
1629 | err_free: | |
1630 | while (i--) | |
1631 | gpio_free((--array)->gpio); | |
1632 | return err; | |
1633 | } | |
1634 | EXPORT_SYMBOL_GPL(gpio_request_array); | |
1635 | ||
1636 | /** | |
1637 | * gpio_free_array - release multiple GPIOs in a single call | |
1638 | * @array: array of the 'struct gpio' | |
1639 | * @num: how many GPIOs in the array | |
1640 | */ | |
7c295975 | 1641 | void gpio_free_array(const struct gpio *array, size_t num) |
3e45f1d1 EM |
1642 | { |
1643 | while (num--) | |
1644 | gpio_free((array++)->gpio); | |
1645 | } | |
1646 | EXPORT_SYMBOL_GPL(gpio_free_array); | |
d2876d08 DB |
1647 | |
1648 | /** | |
1649 | * gpiochip_is_requested - return string iff signal was requested | |
1650 | * @chip: controller managing the signal | |
1651 | * @offset: of signal within controller's 0..(ngpio - 1) range | |
1652 | * | |
1653 | * Returns NULL if the GPIO is not currently requested, else a string. | |
1654 | * If debugfs support is enabled, the string returned is the label passed | |
1655 | * to gpio_request(); otherwise it is a meaningless constant. | |
1656 | * | |
1657 | * This function is for use by GPIO controller drivers. The label can | |
1658 | * help with diagnostics, and knowing that the signal is used as a GPIO | |
1659 | * can help avoid accidentally multiplexing it to another controller. | |
1660 | */ | |
1661 | const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) | |
1662 | { | |
6c0b4e6c | 1663 | struct gpio_desc *desc; |
d2876d08 | 1664 | |
6c0b4e6c | 1665 | if (!GPIO_OFFSET_VALID(chip, offset)) |
d2876d08 | 1666 | return NULL; |
6c0b4e6c AC |
1667 | |
1668 | desc = &chip->desc[offset]; | |
1669 | ||
372e722e | 1670 | if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) |
d2876d08 DB |
1671 | return NULL; |
1672 | #ifdef CONFIG_DEBUG_FS | |
372e722e | 1673 | return desc->label; |
d2876d08 DB |
1674 | #else |
1675 | return "?"; | |
1676 | #endif | |
1677 | } | |
1678 | EXPORT_SYMBOL_GPL(gpiochip_is_requested); | |
1679 | ||
1680 | ||
1681 | /* Drivers MUST set GPIO direction before making get/set calls. In | |
1682 | * some cases this is done in early boot, before IRQs are enabled. | |
1683 | * | |
1684 | * As a rule these aren't called more than once (except for drivers | |
1685 | * using the open-drain emulation idiom) so these are natural places | |
1686 | * to accumulate extra debugging checks. Note that we can't (yet) | |
1687 | * rely on gpio_request() having been called beforehand. | |
1688 | */ | |
1689 | ||
79a9becd AC |
1690 | /** |
1691 | * gpiod_direction_input - set the GPIO direction to input | |
1692 | * @desc: GPIO to set to input | |
1693 | * | |
1694 | * Set the direction of the passed GPIO to input, such as gpiod_get_value() can | |
1695 | * be called safely on it. | |
1696 | * | |
1697 | * Return 0 in case of success, else an error code. | |
1698 | */ | |
1699 | int gpiod_direction_input(struct gpio_desc *desc) | |
d2876d08 DB |
1700 | { |
1701 | unsigned long flags; | |
1702 | struct gpio_chip *chip; | |
d2876d08 | 1703 | int status = -EINVAL; |
372e722e | 1704 | int offset; |
d2876d08 | 1705 | |
be1a4b13 | 1706 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1707 | pr_warn("%s: invalid GPIO\n", __func__); |
1708 | return -EINVAL; | |
1709 | } | |
1710 | ||
be1a4b13 LW |
1711 | chip = desc->chip; |
1712 | if (!chip->get || !chip->direction_input) { | |
6424de5a MB |
1713 | gpiod_warn(desc, |
1714 | "%s: missing get() or direction_input() operations\n", | |
7589e59f | 1715 | __func__); |
be1a4b13 LW |
1716 | return -EIO; |
1717 | } | |
1718 | ||
d2876d08 DB |
1719 | spin_lock_irqsave(&gpio_lock, flags); |
1720 | ||
372e722e | 1721 | status = gpio_ensure_requested(desc); |
35e8bb51 DB |
1722 | if (status < 0) |
1723 | goto fail; | |
d2876d08 DB |
1724 | |
1725 | /* now we know the gpio is valid and chip won't vanish */ | |
1726 | ||
1727 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1728 | ||
9c4ba946 | 1729 | might_sleep_if(chip->can_sleep); |
d2876d08 | 1730 | |
372e722e | 1731 | offset = gpio_chip_hwgpio(desc); |
35e8bb51 | 1732 | if (status) { |
372e722e | 1733 | status = chip->request(chip, offset); |
35e8bb51 | 1734 | if (status < 0) { |
7589e59f AS |
1735 | gpiod_dbg(desc, "%s: chip request fail, %d\n", |
1736 | __func__, status); | |
35e8bb51 DB |
1737 | /* and it's not available to anyone else ... |
1738 | * gpio_request() is the fully clean solution. | |
1739 | */ | |
1740 | goto lose; | |
1741 | } | |
1742 | } | |
1743 | ||
372e722e | 1744 | status = chip->direction_input(chip, offset); |
d2876d08 DB |
1745 | if (status == 0) |
1746 | clear_bit(FLAG_IS_OUT, &desc->flags); | |
3f397c21 | 1747 | |
372e722e | 1748 | trace_gpio_direction(desc_to_gpio(desc), 1, status); |
35e8bb51 | 1749 | lose: |
d2876d08 DB |
1750 | return status; |
1751 | fail: | |
1752 | spin_unlock_irqrestore(&gpio_lock, flags); | |
bcabdef1 | 1753 | if (status) |
7589e59f | 1754 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
d2876d08 DB |
1755 | return status; |
1756 | } | |
79a9becd | 1757 | EXPORT_SYMBOL_GPL(gpiod_direction_input); |
372e722e | 1758 | |
ef70bbe1 | 1759 | static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) |
d2876d08 DB |
1760 | { |
1761 | unsigned long flags; | |
1762 | struct gpio_chip *chip; | |
d2876d08 | 1763 | int status = -EINVAL; |
372e722e | 1764 | int offset; |
d2876d08 | 1765 | |
d468bf9e LW |
1766 | /* GPIOs used for IRQs shall not be set as output */ |
1767 | if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) { | |
1768 | gpiod_err(desc, | |
1769 | "%s: tried to set a GPIO tied to an IRQ as output\n", | |
1770 | __func__); | |
1771 | return -EIO; | |
1772 | } | |
1773 | ||
aca5ce14 LD |
1774 | /* Open drain pin should not be driven to 1 */ |
1775 | if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
372e722e | 1776 | return gpiod_direction_input(desc); |
aca5ce14 | 1777 | |
25553ff0 LD |
1778 | /* Open source pin should not be driven to 0 */ |
1779 | if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
372e722e | 1780 | return gpiod_direction_input(desc); |
25553ff0 | 1781 | |
be1a4b13 LW |
1782 | chip = desc->chip; |
1783 | if (!chip->set || !chip->direction_output) { | |
6424de5a MB |
1784 | gpiod_warn(desc, |
1785 | "%s: missing set() or direction_output() operations\n", | |
1786 | __func__); | |
be1a4b13 LW |
1787 | return -EIO; |
1788 | } | |
1789 | ||
d2876d08 DB |
1790 | spin_lock_irqsave(&gpio_lock, flags); |
1791 | ||
372e722e | 1792 | status = gpio_ensure_requested(desc); |
35e8bb51 DB |
1793 | if (status < 0) |
1794 | goto fail; | |
d2876d08 DB |
1795 | |
1796 | /* now we know the gpio is valid and chip won't vanish */ | |
1797 | ||
1798 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1799 | ||
9c4ba946 | 1800 | might_sleep_if(chip->can_sleep); |
d2876d08 | 1801 | |
372e722e | 1802 | offset = gpio_chip_hwgpio(desc); |
35e8bb51 | 1803 | if (status) { |
372e722e | 1804 | status = chip->request(chip, offset); |
35e8bb51 | 1805 | if (status < 0) { |
7589e59f AS |
1806 | gpiod_dbg(desc, "%s: chip request fail, %d\n", |
1807 | __func__, status); | |
35e8bb51 DB |
1808 | /* and it's not available to anyone else ... |
1809 | * gpio_request() is the fully clean solution. | |
1810 | */ | |
1811 | goto lose; | |
1812 | } | |
1813 | } | |
1814 | ||
372e722e | 1815 | status = chip->direction_output(chip, offset, value); |
d2876d08 DB |
1816 | if (status == 0) |
1817 | set_bit(FLAG_IS_OUT, &desc->flags); | |
372e722e AC |
1818 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
1819 | trace_gpio_direction(desc_to_gpio(desc), 0, status); | |
35e8bb51 | 1820 | lose: |
d2876d08 DB |
1821 | return status; |
1822 | fail: | |
1823 | spin_unlock_irqrestore(&gpio_lock, flags); | |
bcabdef1 | 1824 | if (status) |
6424de5a | 1825 | gpiod_dbg(desc, "%s: gpio status %d\n", __func__, status); |
d2876d08 DB |
1826 | return status; |
1827 | } | |
ef70bbe1 PZ |
1828 | |
1829 | /** | |
1830 | * gpiod_direction_output_raw - set the GPIO direction to output | |
1831 | * @desc: GPIO to set to output | |
1832 | * @value: initial output value of the GPIO | |
1833 | * | |
1834 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
1835 | * be called safely on it. The initial value of the output must be specified | |
1836 | * as raw value on the physical line without regard for the ACTIVE_LOW status. | |
1837 | * | |
1838 | * Return 0 in case of success, else an error code. | |
1839 | */ | |
1840 | int gpiod_direction_output_raw(struct gpio_desc *desc, int value) | |
1841 | { | |
1842 | if (!desc || !desc->chip) { | |
1843 | pr_warn("%s: invalid GPIO\n", __func__); | |
1844 | return -EINVAL; | |
1845 | } | |
1846 | return _gpiod_direction_output_raw(desc, value); | |
1847 | } | |
1848 | EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); | |
1849 | ||
1850 | /** | |
90df4fe0 | 1851 | * gpiod_direction_output - set the GPIO direction to output |
ef70bbe1 PZ |
1852 | * @desc: GPIO to set to output |
1853 | * @value: initial output value of the GPIO | |
1854 | * | |
1855 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
1856 | * be called safely on it. The initial value of the output must be specified | |
1857 | * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1858 | * account. | |
1859 | * | |
1860 | * Return 0 in case of success, else an error code. | |
1861 | */ | |
1862 | int gpiod_direction_output(struct gpio_desc *desc, int value) | |
1863 | { | |
1864 | if (!desc || !desc->chip) { | |
1865 | pr_warn("%s: invalid GPIO\n", __func__); | |
1866 | return -EINVAL; | |
1867 | } | |
1868 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1869 | value = !value; | |
1870 | return _gpiod_direction_output_raw(desc, value); | |
1871 | } | |
79a9becd | 1872 | EXPORT_SYMBOL_GPL(gpiod_direction_output); |
d2876d08 | 1873 | |
c4b5be98 | 1874 | /** |
79a9becd | 1875 | * gpiod_set_debounce - sets @debounce time for a @gpio |
c4b5be98 FB |
1876 | * @gpio: the gpio to set debounce time |
1877 | * @debounce: debounce time is microseconds | |
65d87656 LW |
1878 | * |
1879 | * returns -ENOTSUPP if the controller does not support setting | |
1880 | * debounce. | |
c4b5be98 | 1881 | */ |
79a9becd | 1882 | int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) |
c4b5be98 FB |
1883 | { |
1884 | unsigned long flags; | |
1885 | struct gpio_chip *chip; | |
c4b5be98 | 1886 | int status = -EINVAL; |
372e722e | 1887 | int offset; |
c4b5be98 | 1888 | |
be1a4b13 | 1889 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1890 | pr_warn("%s: invalid GPIO\n", __func__); |
1891 | return -EINVAL; | |
1892 | } | |
1893 | ||
c4b5be98 | 1894 | chip = desc->chip; |
be1a4b13 | 1895 | if (!chip->set || !chip->set_debounce) { |
6424de5a MB |
1896 | gpiod_dbg(desc, |
1897 | "%s: missing set() or set_debounce() operations\n", | |
1898 | __func__); | |
65d87656 | 1899 | return -ENOTSUPP; |
be1a4b13 LW |
1900 | } |
1901 | ||
1902 | spin_lock_irqsave(&gpio_lock, flags); | |
372e722e AC |
1903 | |
1904 | status = gpio_ensure_requested(desc); | |
c4b5be98 FB |
1905 | if (status < 0) |
1906 | goto fail; | |
1907 | ||
1908 | /* now we know the gpio is valid and chip won't vanish */ | |
1909 | ||
1910 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1911 | ||
9c4ba946 | 1912 | might_sleep_if(chip->can_sleep); |
c4b5be98 | 1913 | |
372e722e AC |
1914 | offset = gpio_chip_hwgpio(desc); |
1915 | return chip->set_debounce(chip, offset, debounce); | |
c4b5be98 FB |
1916 | |
1917 | fail: | |
1918 | spin_unlock_irqrestore(&gpio_lock, flags); | |
bcabdef1 | 1919 | if (status) |
6424de5a | 1920 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
c4b5be98 FB |
1921 | |
1922 | return status; | |
1923 | } | |
79a9becd | 1924 | EXPORT_SYMBOL_GPL(gpiod_set_debounce); |
372e722e | 1925 | |
79a9becd AC |
1926 | /** |
1927 | * gpiod_is_active_low - test whether a GPIO is active-low or not | |
1928 | * @desc: the gpio descriptor to test | |
1929 | * | |
1930 | * Returns 1 if the GPIO is active-low, 0 otherwise. | |
1931 | */ | |
1932 | int gpiod_is_active_low(const struct gpio_desc *desc) | |
372e722e | 1933 | { |
79a9becd | 1934 | return test_bit(FLAG_ACTIVE_LOW, &desc->flags); |
372e722e | 1935 | } |
79a9becd | 1936 | EXPORT_SYMBOL_GPL(gpiod_is_active_low); |
d2876d08 DB |
1937 | |
1938 | /* I/O calls are only valid after configuration completed; the relevant | |
1939 | * "is this a valid GPIO" error checks should already have been done. | |
1940 | * | |
1941 | * "Get" operations are often inlinable as reading a pin value register, | |
1942 | * and masking the relevant bit in that register. | |
1943 | * | |
1944 | * When "set" operations are inlinable, they involve writing that mask to | |
1945 | * one register to set a low value, or a different register to set it high. | |
1946 | * Otherwise locking is needed, so there may be little value to inlining. | |
1947 | * | |
1948 | *------------------------------------------------------------------------ | |
1949 | * | |
1950 | * IMPORTANT!!! The hot paths -- get/set value -- assume that callers | |
1951 | * have requested the GPIO. That can include implicit requesting by | |
1952 | * a direction setting call. Marking a gpio as requested locks its chip | |
1953 | * in memory, guaranteeing that these table lookups need no more locking | |
1954 | * and that gpiochip_remove() will fail. | |
1955 | * | |
1956 | * REVISIT when debugging, consider adding some instrumentation to ensure | |
1957 | * that the GPIO was actually requested. | |
1958 | */ | |
1959 | ||
79a9becd | 1960 | static int _gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 DB |
1961 | { |
1962 | struct gpio_chip *chip; | |
3f397c21 | 1963 | int value; |
372e722e | 1964 | int offset; |
d2876d08 | 1965 | |
372e722e AC |
1966 | chip = desc->chip; |
1967 | offset = gpio_chip_hwgpio(desc); | |
372e722e AC |
1968 | value = chip->get ? chip->get(chip, offset) : 0; |
1969 | trace_gpio_value(desc_to_gpio(desc), 1, value); | |
3f397c21 | 1970 | return value; |
d2876d08 | 1971 | } |
372e722e | 1972 | |
d2876d08 | 1973 | /** |
79a9becd AC |
1974 | * gpiod_get_raw_value() - return a gpio's raw value |
1975 | * @desc: gpio whose value will be returned | |
d2876d08 | 1976 | * |
79a9becd AC |
1977 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding |
1978 | * its ACTIVE_LOW status. | |
1979 | * | |
1980 | * This function should be called from contexts where we cannot sleep, and will | |
1981 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1982 | */ |
79a9becd | 1983 | int gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 | 1984 | { |
bcabdef1 AC |
1985 | if (!desc) |
1986 | return 0; | |
e4e449e8 | 1987 | /* Should be using gpio_get_value_cansleep() */ |
d8e0ac08 | 1988 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 1989 | return _gpiod_get_raw_value(desc); |
d2876d08 | 1990 | } |
79a9becd | 1991 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value); |
372e722e | 1992 | |
79a9becd AC |
1993 | /** |
1994 | * gpiod_get_value() - return a gpio's value | |
1995 | * @desc: gpio whose value will be returned | |
1996 | * | |
1997 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
1998 | * account. | |
1999 | * | |
2000 | * This function should be called from contexts where we cannot sleep, and will | |
2001 | * complain if the GPIO chip functions potentially sleep. | |
2002 | */ | |
2003 | int gpiod_get_value(const struct gpio_desc *desc) | |
372e722e | 2004 | { |
79a9becd AC |
2005 | int value; |
2006 | if (!desc) | |
2007 | return 0; | |
2008 | /* Should be using gpio_get_value_cansleep() */ | |
2009 | WARN_ON(desc->chip->can_sleep); | |
2010 | ||
2011 | value = _gpiod_get_raw_value(desc); | |
2012 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2013 | value = !value; | |
2014 | ||
2015 | return value; | |
372e722e | 2016 | } |
79a9becd | 2017 | EXPORT_SYMBOL_GPL(gpiod_get_value); |
d2876d08 | 2018 | |
aca5ce14 LD |
2019 | /* |
2020 | * _gpio_set_open_drain_value() - Set the open drain gpio's value. | |
79a9becd | 2021 | * @desc: gpio descriptor whose state need to be set. |
aca5ce14 LD |
2022 | * @value: Non-zero for setting it HIGH otherise it will set to LOW. |
2023 | */ | |
372e722e | 2024 | static void _gpio_set_open_drain_value(struct gpio_desc *desc, int value) |
aca5ce14 LD |
2025 | { |
2026 | int err = 0; | |
372e722e AC |
2027 | struct gpio_chip *chip = desc->chip; |
2028 | int offset = gpio_chip_hwgpio(desc); | |
2029 | ||
aca5ce14 | 2030 | if (value) { |
372e722e | 2031 | err = chip->direction_input(chip, offset); |
aca5ce14 | 2032 | if (!err) |
372e722e | 2033 | clear_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 2034 | } else { |
372e722e | 2035 | err = chip->direction_output(chip, offset, 0); |
aca5ce14 | 2036 | if (!err) |
372e722e | 2037 | set_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 2038 | } |
372e722e | 2039 | trace_gpio_direction(desc_to_gpio(desc), value, err); |
aca5ce14 | 2040 | if (err < 0) |
6424de5a MB |
2041 | gpiod_err(desc, |
2042 | "%s: Error in set_value for open drain err %d\n", | |
2043 | __func__, err); | |
aca5ce14 LD |
2044 | } |
2045 | ||
25553ff0 | 2046 | /* |
79a9becd AC |
2047 | * _gpio_set_open_source_value() - Set the open source gpio's value. |
2048 | * @desc: gpio descriptor whose state need to be set. | |
25553ff0 LD |
2049 | * @value: Non-zero for setting it HIGH otherise it will set to LOW. |
2050 | */ | |
372e722e | 2051 | static void _gpio_set_open_source_value(struct gpio_desc *desc, int value) |
25553ff0 LD |
2052 | { |
2053 | int err = 0; | |
372e722e AC |
2054 | struct gpio_chip *chip = desc->chip; |
2055 | int offset = gpio_chip_hwgpio(desc); | |
2056 | ||
25553ff0 | 2057 | if (value) { |
372e722e | 2058 | err = chip->direction_output(chip, offset, 1); |
25553ff0 | 2059 | if (!err) |
372e722e | 2060 | set_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 2061 | } else { |
372e722e | 2062 | err = chip->direction_input(chip, offset); |
25553ff0 | 2063 | if (!err) |
372e722e | 2064 | clear_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 2065 | } |
372e722e | 2066 | trace_gpio_direction(desc_to_gpio(desc), !value, err); |
25553ff0 | 2067 | if (err < 0) |
6424de5a MB |
2068 | gpiod_err(desc, |
2069 | "%s: Error in set_value for open source err %d\n", | |
2070 | __func__, err); | |
25553ff0 LD |
2071 | } |
2072 | ||
79a9becd | 2073 | static void _gpiod_set_raw_value(struct gpio_desc *desc, int value) |
d2876d08 DB |
2074 | { |
2075 | struct gpio_chip *chip; | |
2076 | ||
372e722e | 2077 | chip = desc->chip; |
372e722e AC |
2078 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
2079 | if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
2080 | _gpio_set_open_drain_value(desc, value); | |
2081 | else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
2082 | _gpio_set_open_source_value(desc, value); | |
aca5ce14 | 2083 | else |
372e722e AC |
2084 | chip->set(chip, gpio_chip_hwgpio(desc), value); |
2085 | } | |
2086 | ||
d2876d08 | 2087 | /** |
79a9becd AC |
2088 | * gpiod_set_raw_value() - assign a gpio's raw value |
2089 | * @desc: gpio whose value will be assigned | |
d2876d08 | 2090 | * @value: value to assign |
d2876d08 | 2091 | * |
79a9becd AC |
2092 | * Set the raw value of the GPIO, i.e. the value of its physical line without |
2093 | * regard for its ACTIVE_LOW status. | |
2094 | * | |
2095 | * This function should be called from contexts where we cannot sleep, and will | |
2096 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 2097 | */ |
79a9becd | 2098 | void gpiod_set_raw_value(struct gpio_desc *desc, int value) |
372e722e | 2099 | { |
bcabdef1 AC |
2100 | if (!desc) |
2101 | return; | |
e4e449e8 | 2102 | /* Should be using gpio_set_value_cansleep() */ |
d8e0ac08 | 2103 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 2104 | _gpiod_set_raw_value(desc, value); |
d2876d08 | 2105 | } |
79a9becd | 2106 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value); |
d2876d08 DB |
2107 | |
2108 | /** | |
79a9becd AC |
2109 | * gpiod_set_value() - assign a gpio's value |
2110 | * @desc: gpio whose value will be assigned | |
2111 | * @value: value to assign | |
2112 | * | |
2113 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
2114 | * account | |
d2876d08 | 2115 | * |
79a9becd AC |
2116 | * This function should be called from contexts where we cannot sleep, and will |
2117 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 2118 | */ |
79a9becd | 2119 | void gpiod_set_value(struct gpio_desc *desc, int value) |
d2876d08 | 2120 | { |
bcabdef1 | 2121 | if (!desc) |
79a9becd AC |
2122 | return; |
2123 | /* Should be using gpio_set_value_cansleep() */ | |
2124 | WARN_ON(desc->chip->can_sleep); | |
2125 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2126 | value = !value; | |
2127 | _gpiod_set_raw_value(desc, value); | |
372e722e | 2128 | } |
79a9becd | 2129 | EXPORT_SYMBOL_GPL(gpiod_set_value); |
d2876d08 | 2130 | |
d2876d08 | 2131 | /** |
79a9becd AC |
2132 | * gpiod_cansleep() - report whether gpio value access may sleep |
2133 | * @desc: gpio to check | |
d2876d08 | 2134 | * |
d2876d08 | 2135 | */ |
79a9becd | 2136 | int gpiod_cansleep(const struct gpio_desc *desc) |
372e722e | 2137 | { |
bcabdef1 AC |
2138 | if (!desc) |
2139 | return 0; | |
372e722e | 2140 | return desc->chip->can_sleep; |
d2876d08 | 2141 | } |
79a9becd | 2142 | EXPORT_SYMBOL_GPL(gpiod_cansleep); |
d2876d08 | 2143 | |
0f6d504e | 2144 | /** |
79a9becd AC |
2145 | * gpiod_to_irq() - return the IRQ corresponding to a GPIO |
2146 | * @desc: gpio whose IRQ will be returned (already requested) | |
0f6d504e | 2147 | * |
79a9becd AC |
2148 | * Return the IRQ corresponding to the passed GPIO, or an error code in case of |
2149 | * error. | |
0f6d504e | 2150 | */ |
79a9becd | 2151 | int gpiod_to_irq(const struct gpio_desc *desc) |
0f6d504e DB |
2152 | { |
2153 | struct gpio_chip *chip; | |
372e722e | 2154 | int offset; |
0f6d504e | 2155 | |
bcabdef1 AC |
2156 | if (!desc) |
2157 | return -EINVAL; | |
372e722e AC |
2158 | chip = desc->chip; |
2159 | offset = gpio_chip_hwgpio(desc); | |
2160 | return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO; | |
0f6d504e | 2161 | } |
79a9becd | 2162 | EXPORT_SYMBOL_GPL(gpiod_to_irq); |
0f6d504e | 2163 | |
d468bf9e LW |
2164 | /** |
2165 | * gpiod_lock_as_irq() - lock a GPIO to be used as IRQ | |
2166 | * @gpio: the GPIO line to lock as used for IRQ | |
2167 | * | |
2168 | * This is used directly by GPIO drivers that want to lock down | |
2169 | * a certain GPIO line to be used as IRQs, for example in the | |
2170 | * .to_irq() callback of their gpio_chip, or in the .irq_enable() | |
2171 | * of its irq_chip implementation if the GPIO is known from that | |
2172 | * code. | |
2173 | */ | |
79a9becd | 2174 | int gpiod_lock_as_irq(struct gpio_desc *desc) |
372e722e | 2175 | { |
d468bf9e LW |
2176 | if (!desc) |
2177 | return -EINVAL; | |
2178 | ||
2179 | if (test_bit(FLAG_IS_OUT, &desc->flags)) { | |
2180 | gpiod_err(desc, | |
2181 | "%s: tried to flag a GPIO set as output for IRQ\n", | |
2182 | __func__); | |
2183 | return -EIO; | |
2184 | } | |
2185 | ||
2186 | set_bit(FLAG_USED_AS_IRQ, &desc->flags); | |
2187 | return 0; | |
372e722e | 2188 | } |
79a9becd | 2189 | EXPORT_SYMBOL_GPL(gpiod_lock_as_irq); |
d2876d08 | 2190 | |
d468bf9e LW |
2191 | int gpio_lock_as_irq(struct gpio_chip *chip, unsigned int offset) |
2192 | { | |
2193 | return gpiod_lock_as_irq(gpiochip_offset_to_desc(chip, offset)); | |
2194 | } | |
2195 | EXPORT_SYMBOL_GPL(gpio_lock_as_irq); | |
d2876d08 | 2196 | |
d468bf9e LW |
2197 | /** |
2198 | * gpiod_unlock_as_irq() - unlock a GPIO used as IRQ | |
2199 | * @gpio: the GPIO line to unlock from IRQ usage | |
2200 | * | |
2201 | * This is used directly by GPIO drivers that want to indicate | |
2202 | * that a certain GPIO is no longer used exclusively for IRQ. | |
d2876d08 | 2203 | */ |
79a9becd | 2204 | void gpiod_unlock_as_irq(struct gpio_desc *desc) |
d468bf9e LW |
2205 | { |
2206 | if (!desc) | |
2207 | return; | |
d2876d08 | 2208 | |
d468bf9e LW |
2209 | clear_bit(FLAG_USED_AS_IRQ, &desc->flags); |
2210 | } | |
79a9becd | 2211 | EXPORT_SYMBOL_GPL(gpiod_unlock_as_irq); |
d468bf9e LW |
2212 | |
2213 | void gpio_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) | |
2214 | { | |
2215 | return gpiod_unlock_as_irq(gpiochip_offset_to_desc(chip, offset)); | |
2216 | } | |
2217 | EXPORT_SYMBOL_GPL(gpio_unlock_as_irq); | |
d2876d08 | 2218 | |
79a9becd AC |
2219 | /** |
2220 | * gpiod_get_raw_value_cansleep() - return a gpio's raw value | |
2221 | * @desc: gpio whose value will be returned | |
2222 | * | |
2223 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding | |
2224 | * its ACTIVE_LOW status. | |
2225 | * | |
2226 | * This function is to be called from contexts that can sleep. | |
d2876d08 | 2227 | */ |
79a9becd | 2228 | int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) |
d2876d08 | 2229 | { |
d2876d08 | 2230 | might_sleep_if(extra_checks); |
bcabdef1 AC |
2231 | if (!desc) |
2232 | return 0; | |
79a9becd | 2233 | return _gpiod_get_raw_value(desc); |
d2876d08 | 2234 | } |
79a9becd | 2235 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); |
372e722e | 2236 | |
79a9becd AC |
2237 | /** |
2238 | * gpiod_get_value_cansleep() - return a gpio's value | |
2239 | * @desc: gpio whose value will be returned | |
2240 | * | |
2241 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
2242 | * account. | |
2243 | * | |
2244 | * This function is to be called from contexts that can sleep. | |
2245 | */ | |
2246 | int gpiod_get_value_cansleep(const struct gpio_desc *desc) | |
d2876d08 | 2247 | { |
3f397c21 | 2248 | int value; |
d2876d08 DB |
2249 | |
2250 | might_sleep_if(extra_checks); | |
bcabdef1 AC |
2251 | if (!desc) |
2252 | return 0; | |
79a9becd AC |
2253 | |
2254 | value = _gpiod_get_raw_value(desc); | |
2255 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2256 | value = !value; | |
2257 | ||
3f397c21 | 2258 | return value; |
d2876d08 | 2259 | } |
79a9becd | 2260 | EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); |
372e722e | 2261 | |
79a9becd AC |
2262 | /** |
2263 | * gpiod_set_raw_value_cansleep() - assign a gpio's raw value | |
2264 | * @desc: gpio whose value will be assigned | |
2265 | * @value: value to assign | |
2266 | * | |
2267 | * Set the raw value of the GPIO, i.e. the value of its physical line without | |
2268 | * regard for its ACTIVE_LOW status. | |
2269 | * | |
2270 | * This function is to be called from contexts that can sleep. | |
2271 | */ | |
2272 | void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) | |
372e722e | 2273 | { |
d2876d08 | 2274 | might_sleep_if(extra_checks); |
bcabdef1 AC |
2275 | if (!desc) |
2276 | return; | |
79a9becd | 2277 | _gpiod_set_raw_value(desc, value); |
372e722e | 2278 | } |
79a9becd | 2279 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); |
d2876d08 | 2280 | |
79a9becd AC |
2281 | /** |
2282 | * gpiod_set_value_cansleep() - assign a gpio's value | |
2283 | * @desc: gpio whose value will be assigned | |
2284 | * @value: value to assign | |
2285 | * | |
2286 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
2287 | * account | |
2288 | * | |
2289 | * This function is to be called from contexts that can sleep. | |
2290 | */ | |
2291 | void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) | |
d2876d08 | 2292 | { |
d2876d08 | 2293 | might_sleep_if(extra_checks); |
bcabdef1 AC |
2294 | if (!desc) |
2295 | return; | |
79a9becd AC |
2296 | |
2297 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2298 | value = !value; | |
2299 | _gpiod_set_raw_value(desc, value); | |
372e722e | 2300 | } |
79a9becd | 2301 | EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); |
d2876d08 | 2302 | |
bae48da2 | 2303 | /** |
ad824783 AC |
2304 | * gpiod_add_lookup_table() - register GPIO device consumers |
2305 | * @table: table of consumers to register | |
bae48da2 | 2306 | */ |
ad824783 | 2307 | void gpiod_add_lookup_table(struct gpiod_lookup_table *table) |
bae48da2 AC |
2308 | { |
2309 | mutex_lock(&gpio_lookup_lock); | |
2310 | ||
ad824783 | 2311 | list_add_tail(&table->list, &gpio_lookup_list); |
bae48da2 AC |
2312 | |
2313 | mutex_unlock(&gpio_lookup_lock); | |
2314 | } | |
2315 | ||
bae48da2 AC |
2316 | #ifdef CONFIG_OF |
2317 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, | |
53e7cac3 AC |
2318 | unsigned int idx, |
2319 | enum gpio_lookup_flags *flags) | |
bae48da2 AC |
2320 | { |
2321 | char prop_name[32]; /* 32 is max size of property name */ | |
2322 | enum of_gpio_flags of_flags; | |
2323 | struct gpio_desc *desc; | |
2324 | ||
2325 | if (con_id) | |
2326 | snprintf(prop_name, 32, "%s-gpios", con_id); | |
aca5ce14 | 2327 | else |
bae48da2 AC |
2328 | snprintf(prop_name, 32, "gpios"); |
2329 | ||
2330 | desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx, | |
2331 | &of_flags); | |
2332 | ||
2333 | if (IS_ERR(desc)) | |
2334 | return desc; | |
2335 | ||
2336 | if (of_flags & OF_GPIO_ACTIVE_LOW) | |
53e7cac3 | 2337 | *flags |= GPIO_ACTIVE_LOW; |
bae48da2 AC |
2338 | |
2339 | return desc; | |
2340 | } | |
2341 | #else | |
2342 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, | |
209e64f9 AC |
2343 | unsigned int idx, |
2344 | enum gpio_lookup_flags *flags) | |
bae48da2 AC |
2345 | { |
2346 | return ERR_PTR(-ENODEV); | |
d2876d08 | 2347 | } |
bae48da2 | 2348 | #endif |
d2876d08 | 2349 | |
81f59e9d | 2350 | static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id, |
53e7cac3 AC |
2351 | unsigned int idx, |
2352 | enum gpio_lookup_flags *flags) | |
372e722e | 2353 | { |
e01f440a MW |
2354 | struct acpi_gpio_info info; |
2355 | struct gpio_desc *desc; | |
2356 | ||
2357 | desc = acpi_get_gpiod_by_index(dev, idx, &info); | |
2358 | if (IS_ERR(desc)) | |
2359 | return desc; | |
2360 | ||
2361 | if (info.gpioint && info.active_low) | |
53e7cac3 | 2362 | *flags |= GPIO_ACTIVE_LOW; |
e01f440a MW |
2363 | |
2364 | return desc; | |
81f59e9d MW |
2365 | } |
2366 | ||
ad824783 | 2367 | static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) |
bae48da2 AC |
2368 | { |
2369 | const char *dev_id = dev ? dev_name(dev) : NULL; | |
ad824783 | 2370 | struct gpiod_lookup_table *table; |
bae48da2 AC |
2371 | |
2372 | mutex_lock(&gpio_lookup_lock); | |
2373 | ||
ad824783 AC |
2374 | list_for_each_entry(table, &gpio_lookup_list, list) { |
2375 | if (table->dev_id && dev_id) { | |
2376 | /* | |
2377 | * Valid strings on both ends, must be identical to have | |
2378 | * a match | |
2379 | */ | |
2380 | if (!strcmp(table->dev_id, dev_id)) | |
2381 | goto found; | |
2382 | } else { | |
2383 | /* | |
2384 | * One of the pointers is NULL, so both must be to have | |
2385 | * a match | |
2386 | */ | |
2387 | if (dev_id == table->dev_id) | |
2388 | goto found; | |
2389 | } | |
2390 | } | |
2391 | table = NULL; | |
bae48da2 | 2392 | |
ad824783 AC |
2393 | found: |
2394 | mutex_unlock(&gpio_lookup_lock); | |
2395 | return table; | |
2396 | } | |
bae48da2 | 2397 | |
ad824783 AC |
2398 | static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, |
2399 | unsigned int idx, | |
2400 | enum gpio_lookup_flags *flags) | |
2401 | { | |
2a3cf6a3 | 2402 | struct gpio_desc *desc = ERR_PTR(-ENOENT); |
ad824783 AC |
2403 | struct gpiod_lookup_table *table; |
2404 | struct gpiod_lookup *p; | |
bae48da2 | 2405 | |
ad824783 AC |
2406 | table = gpiod_find_lookup_table(dev); |
2407 | if (!table) | |
2408 | return desc; | |
bae48da2 | 2409 | |
ad824783 AC |
2410 | for (p = &table->table[0]; p->chip_label; p++) { |
2411 | struct gpio_chip *chip; | |
bae48da2 | 2412 | |
ad824783 | 2413 | /* idx must always match exactly */ |
bae48da2 AC |
2414 | if (p->idx != idx) |
2415 | continue; | |
2416 | ||
ad824783 AC |
2417 | /* If the lookup entry has a con_id, require exact match */ |
2418 | if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) | |
2419 | continue; | |
bae48da2 | 2420 | |
ad824783 | 2421 | chip = find_chip_by_name(p->chip_label); |
bae48da2 | 2422 | |
ad824783 | 2423 | if (!chip) { |
2a3cf6a3 AC |
2424 | dev_err(dev, "cannot find GPIO chip %s\n", |
2425 | p->chip_label); | |
2426 | return ERR_PTR(-ENODEV); | |
ad824783 | 2427 | } |
bae48da2 | 2428 | |
ad824783 | 2429 | if (chip->ngpio <= p->chip_hwnum) { |
2a3cf6a3 AC |
2430 | dev_err(dev, |
2431 | "requested GPIO %d is out of range [0..%d] for chip %s\n", | |
2432 | idx, chip->ngpio, chip->label); | |
2433 | return ERR_PTR(-EINVAL); | |
bae48da2 | 2434 | } |
bae48da2 | 2435 | |
ad824783 AC |
2436 | desc = gpiochip_offset_to_desc(chip, p->chip_hwnum); |
2437 | *flags = p->flags; | |
bae48da2 | 2438 | |
2a3cf6a3 | 2439 | return desc; |
bae48da2 AC |
2440 | } |
2441 | ||
bae48da2 AC |
2442 | return desc; |
2443 | } | |
2444 | ||
2445 | /** | |
2446 | * gpio_get - obtain a GPIO for a given GPIO function | |
ad824783 | 2447 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 AC |
2448 | * @con_id: function within the GPIO consumer |
2449 | * | |
2450 | * Return the GPIO descriptor corresponding to the function con_id of device | |
2a3cf6a3 AC |
2451 | * dev, -ENOENT if no GPIO has been assigned to the requested function, or |
2452 | * another IS_ERR() code if an error occured while trying to acquire the GPIO. | |
bae48da2 AC |
2453 | */ |
2454 | struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id) | |
2455 | { | |
2456 | return gpiod_get_index(dev, con_id, 0); | |
2457 | } | |
2458 | EXPORT_SYMBOL_GPL(gpiod_get); | |
2459 | ||
2460 | /** | |
2461 | * gpiod_get_index - obtain a GPIO from a multi-index GPIO function | |
fdd6a5fe | 2462 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 AC |
2463 | * @con_id: function within the GPIO consumer |
2464 | * @idx: index of the GPIO to obtain in the consumer | |
2465 | * | |
2466 | * This variant of gpiod_get() allows to access GPIOs other than the first | |
2467 | * defined one for functions that define several GPIOs. | |
2468 | * | |
2a3cf6a3 AC |
2469 | * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the |
2470 | * requested function and/or index, or another IS_ERR() code if an error | |
2471 | * occured while trying to acquire the GPIO. | |
bae48da2 AC |
2472 | */ |
2473 | struct gpio_desc *__must_check gpiod_get_index(struct device *dev, | |
2474 | const char *con_id, | |
2475 | unsigned int idx) | |
2476 | { | |
35c5d7fd | 2477 | struct gpio_desc *desc = NULL; |
bae48da2 | 2478 | int status; |
53e7cac3 | 2479 | enum gpio_lookup_flags flags = 0; |
bae48da2 AC |
2480 | |
2481 | dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); | |
2482 | ||
2483 | /* Using device tree? */ | |
2484 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) { | |
2485 | dev_dbg(dev, "using device tree for GPIO lookup\n"); | |
2486 | desc = of_find_gpio(dev, con_id, idx, &flags); | |
81f59e9d MW |
2487 | } else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) { |
2488 | dev_dbg(dev, "using ACPI for GPIO lookup\n"); | |
2489 | desc = acpi_find_gpio(dev, con_id, idx, &flags); | |
35c5d7fd AC |
2490 | } |
2491 | ||
2492 | /* | |
2493 | * Either we are not using DT or ACPI, or their lookup did not return | |
2494 | * a result. In that case, use platform lookup as a fallback. | |
2495 | */ | |
2a3cf6a3 | 2496 | if (!desc || desc == ERR_PTR(-ENOENT)) { |
bae48da2 | 2497 | dev_dbg(dev, "using lookup tables for GPIO lookup"); |
2a3cf6a3 | 2498 | desc = gpiod_find(dev, con_id, idx, &flags); |
bae48da2 AC |
2499 | } |
2500 | ||
2501 | if (IS_ERR(desc)) { | |
351cfe0f | 2502 | dev_dbg(dev, "lookup for GPIO %s failed\n", con_id); |
bae48da2 AC |
2503 | return desc; |
2504 | } | |
2505 | ||
2506 | status = gpiod_request(desc, con_id); | |
2507 | ||
2508 | if (status < 0) | |
2509 | return ERR_PTR(status); | |
2510 | ||
53e7cac3 | 2511 | if (flags & GPIO_ACTIVE_LOW) |
bae48da2 | 2512 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); |
53e7cac3 AC |
2513 | if (flags & GPIO_OPEN_DRAIN) |
2514 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); | |
2515 | if (flags & GPIO_OPEN_SOURCE) | |
2516 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); | |
bae48da2 AC |
2517 | |
2518 | return desc; | |
2519 | } | |
2520 | EXPORT_SYMBOL_GPL(gpiod_get_index); | |
2521 | ||
2522 | /** | |
2523 | * gpiod_put - dispose of a GPIO descriptor | |
2524 | * @desc: GPIO descriptor to dispose of | |
2525 | * | |
2526 | * No descriptor can be used after gpiod_put() has been called on it. | |
2527 | */ | |
2528 | void gpiod_put(struct gpio_desc *desc) | |
2529 | { | |
2530 | gpiod_free(desc); | |
372e722e | 2531 | } |
bae48da2 | 2532 | EXPORT_SYMBOL_GPL(gpiod_put); |
d2876d08 DB |
2533 | |
2534 | #ifdef CONFIG_DEBUG_FS | |
2535 | ||
d2876d08 DB |
2536 | static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip) |
2537 | { | |
2538 | unsigned i; | |
2539 | unsigned gpio = chip->base; | |
6c0b4e6c | 2540 | struct gpio_desc *gdesc = &chip->desc[0]; |
d2876d08 | 2541 | int is_out; |
d468bf9e | 2542 | int is_irq; |
d2876d08 DB |
2543 | |
2544 | for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) { | |
2545 | if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) | |
2546 | continue; | |
2547 | ||
372e722e | 2548 | gpiod_get_direction(gdesc); |
d2876d08 | 2549 | is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); |
d468bf9e LW |
2550 | is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); |
2551 | seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s", | |
d2876d08 DB |
2552 | gpio, gdesc->label, |
2553 | is_out ? "out" : "in ", | |
2554 | chip->get | |
2555 | ? (chip->get(chip, i) ? "hi" : "lo") | |
d468bf9e LW |
2556 | : "? ", |
2557 | is_irq ? "IRQ" : " "); | |
d2876d08 DB |
2558 | seq_printf(s, "\n"); |
2559 | } | |
2560 | } | |
2561 | ||
f9c4a31f | 2562 | static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) |
d2876d08 | 2563 | { |
362432ae | 2564 | unsigned long flags; |
f9c4a31f | 2565 | struct gpio_chip *chip = NULL; |
cb1650d4 | 2566 | loff_t index = *pos; |
d2876d08 | 2567 | |
f9c4a31f | 2568 | s->private = ""; |
d2876d08 | 2569 | |
362432ae | 2570 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 | 2571 | list_for_each_entry(chip, &gpio_chips, list) |
362432ae GL |
2572 | if (index-- == 0) { |
2573 | spin_unlock_irqrestore(&gpio_lock, flags); | |
cb1650d4 | 2574 | return chip; |
f9c4a31f | 2575 | } |
362432ae | 2576 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f | 2577 | |
cb1650d4 | 2578 | return NULL; |
f9c4a31f TR |
2579 | } |
2580 | ||
2581 | static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
2582 | { | |
362432ae | 2583 | unsigned long flags; |
f9c4a31f | 2584 | struct gpio_chip *chip = v; |
f9c4a31f TR |
2585 | void *ret = NULL; |
2586 | ||
362432ae | 2587 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 AC |
2588 | if (list_is_last(&chip->list, &gpio_chips)) |
2589 | ret = NULL; | |
2590 | else | |
2591 | ret = list_entry(chip->list.next, struct gpio_chip, list); | |
362432ae | 2592 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f TR |
2593 | |
2594 | s->private = "\n"; | |
2595 | ++*pos; | |
2596 | ||
2597 | return ret; | |
2598 | } | |
2599 | ||
2600 | static void gpiolib_seq_stop(struct seq_file *s, void *v) | |
2601 | { | |
2602 | } | |
2603 | ||
2604 | static int gpiolib_seq_show(struct seq_file *s, void *v) | |
2605 | { | |
2606 | struct gpio_chip *chip = v; | |
2607 | struct device *dev; | |
2608 | ||
2609 | seq_printf(s, "%sGPIOs %d-%d", (char *)s->private, | |
2610 | chip->base, chip->base + chip->ngpio - 1); | |
2611 | dev = chip->dev; | |
2612 | if (dev) | |
2613 | seq_printf(s, ", %s/%s", dev->bus ? dev->bus->name : "no-bus", | |
2614 | dev_name(dev)); | |
2615 | if (chip->label) | |
2616 | seq_printf(s, ", %s", chip->label); | |
2617 | if (chip->can_sleep) | |
2618 | seq_printf(s, ", can sleep"); | |
2619 | seq_printf(s, ":\n"); | |
2620 | ||
2621 | if (chip->dbg_show) | |
2622 | chip->dbg_show(s, chip); | |
2623 | else | |
2624 | gpiolib_dbg_show(s, chip); | |
2625 | ||
d2876d08 DB |
2626 | return 0; |
2627 | } | |
2628 | ||
f9c4a31f TR |
2629 | static const struct seq_operations gpiolib_seq_ops = { |
2630 | .start = gpiolib_seq_start, | |
2631 | .next = gpiolib_seq_next, | |
2632 | .stop = gpiolib_seq_stop, | |
2633 | .show = gpiolib_seq_show, | |
2634 | }; | |
2635 | ||
d2876d08 DB |
2636 | static int gpiolib_open(struct inode *inode, struct file *file) |
2637 | { | |
f9c4a31f | 2638 | return seq_open(file, &gpiolib_seq_ops); |
d2876d08 DB |
2639 | } |
2640 | ||
828c0950 | 2641 | static const struct file_operations gpiolib_operations = { |
f9c4a31f | 2642 | .owner = THIS_MODULE, |
d2876d08 DB |
2643 | .open = gpiolib_open, |
2644 | .read = seq_read, | |
2645 | .llseek = seq_lseek, | |
f9c4a31f | 2646 | .release = seq_release, |
d2876d08 DB |
2647 | }; |
2648 | ||
2649 | static int __init gpiolib_debugfs_init(void) | |
2650 | { | |
2651 | /* /sys/kernel/debug/gpio */ | |
2652 | (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO, | |
2653 | NULL, NULL, &gpiolib_operations); | |
2654 | return 0; | |
2655 | } | |
2656 | subsys_initcall(gpiolib_debugfs_init); | |
2657 | ||
2658 | #endif /* DEBUG_FS */ |