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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> |
81f59e9d | 13 | #include <linux/acpi_gpio.h> |
ff77c352 | 14 | #include <linux/idr.h> |
5a0e3ad6 | 15 | #include <linux/slab.h> |
7b199811 | 16 | #include <linux/acpi.h> |
53e7cac3 | 17 | #include <linux/gpio/driver.h> |
d2876d08 | 18 | |
3f397c21 UKK |
19 | #define CREATE_TRACE_POINTS |
20 | #include <trace/events/gpio.h> | |
d2876d08 | 21 | |
79a9becd | 22 | /* Implementation infrastructure for GPIO interfaces. |
d2876d08 | 23 | * |
79a9becd AC |
24 | * The GPIO programming interface allows for inlining speed-critical |
25 | * get/set operations for common cases, so that access to SOC-integrated | |
26 | * GPIOs can sometimes cost only an instruction or two per bit. | |
d2876d08 DB |
27 | */ |
28 | ||
29 | ||
30 | /* When debugging, extend minimal trust to callers and platform code. | |
31 | * Also emit diagnostic messages that may help initial bringup, when | |
32 | * board setup or driver bugs are most common. | |
33 | * | |
34 | * Otherwise, minimize overhead in what may be bitbanging codepaths. | |
35 | */ | |
36 | #ifdef DEBUG | |
37 | #define extra_checks 1 | |
38 | #else | |
39 | #define extra_checks 0 | |
40 | #endif | |
41 | ||
42 | /* gpio_lock prevents conflicts during gpio_desc[] table updates. | |
43 | * While any GPIO is requested, its gpio_chip is not removable; | |
44 | * each GPIO's "requested" flag serves as a lock and refcount. | |
45 | */ | |
46 | static DEFINE_SPINLOCK(gpio_lock); | |
47 | ||
48 | struct gpio_desc { | |
49 | struct gpio_chip *chip; | |
50 | unsigned long flags; | |
51 | /* flag symbols are bit numbers */ | |
52 | #define FLAG_REQUESTED 0 | |
53 | #define FLAG_IS_OUT 1 | |
710b40ea AC |
54 | #define FLAG_EXPORT 2 /* protected by sysfs_lock */ |
55 | #define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */ | |
56 | #define FLAG_TRIG_FALL 4 /* trigger on falling edge */ | |
57 | #define FLAG_TRIG_RISE 5 /* trigger on rising edge */ | |
79a9becd | 58 | #define FLAG_ACTIVE_LOW 6 /* value has active low */ |
710b40ea AC |
59 | #define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */ |
60 | #define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */ | |
d468bf9e | 61 | #define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */ |
ff77c352 | 62 | |
5ba1821d | 63 | #define ID_SHIFT 16 /* add new flags before this one */ |
ff77c352 | 64 | |
5ba1821d | 65 | #define GPIO_FLAGS_MASK ((1 << ID_SHIFT) - 1) |
ff77c352 | 66 | #define GPIO_TRIGGER_MASK (BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE)) |
d2876d08 DB |
67 | |
68 | #ifdef CONFIG_DEBUG_FS | |
69 | const char *label; | |
70 | #endif | |
71 | }; | |
72 | static struct gpio_desc gpio_desc[ARCH_NR_GPIOS]; | |
73 | ||
6c0b4e6c AC |
74 | #define GPIO_OFFSET_VALID(chip, offset) (offset >= 0 && offset < chip->ngpio) |
75 | ||
bae48da2 AC |
76 | static DEFINE_MUTEX(gpio_lookup_lock); |
77 | static LIST_HEAD(gpio_lookup_list); | |
1a989d0f AC |
78 | static LIST_HEAD(gpio_chips); |
79 | ||
ff77c352 | 80 | #ifdef CONFIG_GPIO_SYSFS |
5ba1821d | 81 | static DEFINE_IDR(dirent_idr); |
ff77c352 DG |
82 | #endif |
83 | ||
372e722e AC |
84 | static int gpiod_request(struct gpio_desc *desc, const char *label); |
85 | static void gpiod_free(struct gpio_desc *desc); | |
372e722e | 86 | |
7b17b59f MB |
87 | #ifdef CONFIG_DEBUG_FS |
88 | #define gpiod_emerg(desc, fmt, ...) \ | |
89 | pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \ | |
90 | ##__VA_ARGS__) | |
91 | #define gpiod_crit(desc, fmt, ...) \ | |
92 | pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \ | |
93 | ##__VA_ARGS__) | |
94 | #define gpiod_err(desc, fmt, ...) \ | |
95 | pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \ | |
96 | ##__VA_ARGS__) | |
97 | #define gpiod_warn(desc, fmt, ...) \ | |
98 | pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \ | |
99 | ##__VA_ARGS__) | |
100 | #define gpiod_info(desc, fmt, ...) \ | |
101 | pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \ | |
102 | ##__VA_ARGS__) | |
103 | #define gpiod_dbg(desc, fmt, ...) \ | |
104 | pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label, \ | |
105 | ##__VA_ARGS__) | |
106 | #else | |
6424de5a MB |
107 | #define gpiod_emerg(desc, fmt, ...) \ |
108 | pr_emerg("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) | |
109 | #define gpiod_crit(desc, fmt, ...) \ | |
110 | pr_crit("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) | |
111 | #define gpiod_err(desc, fmt, ...) \ | |
112 | pr_err("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) | |
113 | #define gpiod_warn(desc, fmt, ...) \ | |
114 | pr_warn("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) | |
115 | #define gpiod_info(desc, fmt, ...) \ | |
116 | pr_info("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) | |
117 | #define gpiod_dbg(desc, fmt, ...) \ | |
118 | pr_debug("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) | |
7b17b59f | 119 | #endif |
372e722e | 120 | |
d2876d08 DB |
121 | static inline void desc_set_label(struct gpio_desc *d, const char *label) |
122 | { | |
123 | #ifdef CONFIG_DEBUG_FS | |
124 | d->label = label; | |
125 | #endif | |
126 | } | |
127 | ||
372e722e AC |
128 | /* |
129 | * Return the GPIO number of the passed descriptor relative to its chip | |
130 | */ | |
131 | static int gpio_chip_hwgpio(const struct gpio_desc *desc) | |
132 | { | |
6c0b4e6c | 133 | return desc - &desc->chip->desc[0]; |
372e722e AC |
134 | } |
135 | ||
136 | /** | |
137 | * Convert a GPIO number to its descriptor | |
138 | */ | |
79a9becd | 139 | struct gpio_desc *gpio_to_desc(unsigned gpio) |
372e722e AC |
140 | { |
141 | if (WARN(!gpio_is_valid(gpio), "invalid GPIO %d\n", gpio)) | |
142 | return NULL; | |
143 | else | |
144 | return &gpio_desc[gpio]; | |
145 | } | |
79a9becd | 146 | EXPORT_SYMBOL_GPL(gpio_to_desc); |
372e722e | 147 | |
d468bf9e LW |
148 | /** |
149 | * Convert an offset on a certain chip to a corresponding descriptor | |
150 | */ | |
151 | static struct gpio_desc *gpiochip_offset_to_desc(struct gpio_chip *chip, | |
152 | unsigned int offset) | |
153 | { | |
154 | unsigned int gpio = chip->base + offset; | |
155 | ||
156 | return gpio_to_desc(gpio); | |
157 | } | |
372e722e AC |
158 | |
159 | /** | |
160 | * Convert a GPIO descriptor to the integer namespace. | |
161 | * This should disappear in the future but is needed since we still | |
162 | * use GPIO numbers for error messages and sysfs nodes | |
163 | */ | |
79a9becd | 164 | int desc_to_gpio(const struct gpio_desc *desc) |
372e722e | 165 | { |
8c0fca81 | 166 | return desc - &gpio_desc[0]; |
372e722e | 167 | } |
79a9becd | 168 | EXPORT_SYMBOL_GPL(desc_to_gpio); |
372e722e AC |
169 | |
170 | ||
d2876d08 DB |
171 | /* Warn when drivers omit gpio_request() calls -- legal but ill-advised |
172 | * when setting direction, and otherwise illegal. Until board setup code | |
173 | * and drivers use explicit requests everywhere (which won't happen when | |
174 | * those calls have no teeth) we can't avoid autorequesting. This nag | |
35e8bb51 DB |
175 | * message should motivate switching to explicit requests... so should |
176 | * the weaker cleanup after faults, compared to gpio_request(). | |
8a0cecff DB |
177 | * |
178 | * NOTE: the autorequest mechanism is going away; at this point it's | |
179 | * only "legal" in the sense that (old) code using it won't break yet, | |
180 | * but instead only triggers a WARN() stack dump. | |
d2876d08 | 181 | */ |
372e722e | 182 | static int gpio_ensure_requested(struct gpio_desc *desc) |
d2876d08 | 183 | { |
8a0cecff | 184 | const struct gpio_chip *chip = desc->chip; |
372e722e | 185 | const int gpio = desc_to_gpio(desc); |
35e8bb51 | 186 | |
8a0cecff DB |
187 | if (WARN(test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0, |
188 | "autorequest GPIO-%d\n", gpio)) { | |
35e8bb51 DB |
189 | if (!try_module_get(chip->owner)) { |
190 | pr_err("GPIO-%d: module can't be gotten \n", gpio); | |
191 | clear_bit(FLAG_REQUESTED, &desc->flags); | |
192 | /* lose */ | |
193 | return -EIO; | |
194 | } | |
d2876d08 | 195 | desc_set_label(desc, "[auto]"); |
35e8bb51 DB |
196 | /* caller must chip->request() w/o spinlock */ |
197 | if (chip->request) | |
198 | return 1; | |
d2876d08 | 199 | } |
35e8bb51 | 200 | return 0; |
d2876d08 DB |
201 | } |
202 | ||
79a9becd AC |
203 | /** |
204 | * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs | |
205 | * @desc: descriptor to return the chip of | |
206 | */ | |
207 | struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) | |
372e722e | 208 | { |
bcabdef1 | 209 | return desc ? desc->chip : NULL; |
372e722e | 210 | } |
79a9becd | 211 | EXPORT_SYMBOL_GPL(gpiod_to_chip); |
d2876d08 | 212 | |
8d0aab2f AV |
213 | /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ |
214 | static int gpiochip_find_base(int ngpio) | |
215 | { | |
83cabe33 AC |
216 | struct gpio_chip *chip; |
217 | int base = ARCH_NR_GPIOS - ngpio; | |
8d0aab2f | 218 | |
83cabe33 AC |
219 | list_for_each_entry_reverse(chip, &gpio_chips, list) { |
220 | /* found a free space? */ | |
221 | if (chip->base + chip->ngpio <= base) | |
222 | break; | |
223 | else | |
224 | /* nope, check the space right before the chip */ | |
225 | base = chip->base - ngpio; | |
8d0aab2f AV |
226 | } |
227 | ||
83cabe33 | 228 | if (gpio_is_valid(base)) { |
8d0aab2f | 229 | pr_debug("%s: found new base at %d\n", __func__, base); |
83cabe33 AC |
230 | return base; |
231 | } else { | |
232 | pr_err("%s: cannot find free range\n", __func__); | |
233 | return -ENOSPC; | |
169b6a7a | 234 | } |
169b6a7a AV |
235 | } |
236 | ||
79a9becd AC |
237 | /** |
238 | * gpiod_get_direction - return the current direction of a GPIO | |
239 | * @desc: GPIO to get the direction of | |
240 | * | |
241 | * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error. | |
242 | * | |
243 | * This function may sleep if gpiod_cansleep() is true. | |
244 | */ | |
245 | int gpiod_get_direction(const struct gpio_desc *desc) | |
80b0a602 MN |
246 | { |
247 | struct gpio_chip *chip; | |
372e722e | 248 | unsigned offset; |
80b0a602 MN |
249 | int status = -EINVAL; |
250 | ||
372e722e AC |
251 | chip = gpiod_to_chip(desc); |
252 | offset = gpio_chip_hwgpio(desc); | |
80b0a602 MN |
253 | |
254 | if (!chip->get_direction) | |
255 | return status; | |
256 | ||
372e722e | 257 | status = chip->get_direction(chip, offset); |
80b0a602 MN |
258 | if (status > 0) { |
259 | /* GPIOF_DIR_IN, or other positive */ | |
260 | status = 1; | |
def63433 AC |
261 | /* FLAG_IS_OUT is just a cache of the result of get_direction(), |
262 | * so it does not affect constness per se */ | |
263 | clear_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); | |
80b0a602 MN |
264 | } |
265 | if (status == 0) { | |
266 | /* GPIOF_DIR_OUT */ | |
def63433 | 267 | set_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); |
80b0a602 MN |
268 | } |
269 | return status; | |
270 | } | |
79a9becd | 271 | EXPORT_SYMBOL_GPL(gpiod_get_direction); |
80b0a602 | 272 | |
d8f388d8 DB |
273 | #ifdef CONFIG_GPIO_SYSFS |
274 | ||
275 | /* lock protects against unexport_gpio() being called while | |
276 | * sysfs files are active. | |
277 | */ | |
278 | static DEFINE_MUTEX(sysfs_lock); | |
279 | ||
280 | /* | |
281 | * /sys/class/gpio/gpioN... only for GPIOs that are exported | |
282 | * /direction | |
283 | * * MAY BE OMITTED if kernel won't allow direction changes | |
284 | * * is read/write as "in" or "out" | |
285 | * * may also be written as "high" or "low", initializing | |
286 | * output value as specified ("out" implies "low") | |
287 | * /value | |
288 | * * always readable, subject to hardware behavior | |
289 | * * may be writable, as zero/nonzero | |
ff77c352 DG |
290 | * /edge |
291 | * * configures behavior of poll(2) on /value | |
292 | * * available only if pin can generate IRQs on input | |
293 | * * is read/write as "none", "falling", "rising", or "both" | |
07697461 JN |
294 | * /active_low |
295 | * * configures polarity of /value | |
296 | * * is read/write as zero/nonzero | |
297 | * * also affects existing and subsequent "falling" and "rising" | |
298 | * /edge configuration | |
d8f388d8 DB |
299 | */ |
300 | ||
301 | static ssize_t gpio_direction_show(struct device *dev, | |
302 | struct device_attribute *attr, char *buf) | |
303 | { | |
def63433 | 304 | const struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
305 | ssize_t status; |
306 | ||
307 | mutex_lock(&sysfs_lock); | |
308 | ||
476171ce | 309 | if (!test_bit(FLAG_EXPORT, &desc->flags)) { |
d8f388d8 | 310 | status = -EIO; |
476171ce | 311 | } else { |
372e722e | 312 | gpiod_get_direction(desc); |
d8f388d8 DB |
313 | status = sprintf(buf, "%s\n", |
314 | test_bit(FLAG_IS_OUT, &desc->flags) | |
315 | ? "out" : "in"); | |
476171ce | 316 | } |
d8f388d8 DB |
317 | |
318 | mutex_unlock(&sysfs_lock); | |
319 | return status; | |
320 | } | |
321 | ||
322 | static ssize_t gpio_direction_store(struct device *dev, | |
323 | struct device_attribute *attr, const char *buf, size_t size) | |
324 | { | |
372e722e | 325 | struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
326 | ssize_t status; |
327 | ||
328 | mutex_lock(&sysfs_lock); | |
329 | ||
330 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
331 | status = -EIO; | |
332 | else if (sysfs_streq(buf, "high")) | |
372e722e | 333 | status = gpiod_direction_output(desc, 1); |
d8f388d8 | 334 | else if (sysfs_streq(buf, "out") || sysfs_streq(buf, "low")) |
372e722e | 335 | status = gpiod_direction_output(desc, 0); |
d8f388d8 | 336 | else if (sysfs_streq(buf, "in")) |
372e722e | 337 | status = gpiod_direction_input(desc); |
d8f388d8 DB |
338 | else |
339 | status = -EINVAL; | |
340 | ||
341 | mutex_unlock(&sysfs_lock); | |
342 | return status ? : size; | |
343 | } | |
344 | ||
07697461 | 345 | static /* const */ DEVICE_ATTR(direction, 0644, |
d8f388d8 DB |
346 | gpio_direction_show, gpio_direction_store); |
347 | ||
348 | static ssize_t gpio_value_show(struct device *dev, | |
349 | struct device_attribute *attr, char *buf) | |
350 | { | |
372e722e | 351 | struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
352 | ssize_t status; |
353 | ||
354 | mutex_lock(&sysfs_lock); | |
355 | ||
79a9becd | 356 | if (!test_bit(FLAG_EXPORT, &desc->flags)) |
d8f388d8 | 357 | status = -EIO; |
79a9becd AC |
358 | else |
359 | status = sprintf(buf, "%d\n", gpiod_get_value_cansleep(desc)); | |
d8f388d8 DB |
360 | |
361 | mutex_unlock(&sysfs_lock); | |
362 | return status; | |
363 | } | |
364 | ||
365 | static ssize_t gpio_value_store(struct device *dev, | |
366 | struct device_attribute *attr, const char *buf, size_t size) | |
367 | { | |
372e722e | 368 | struct gpio_desc *desc = dev_get_drvdata(dev); |
d8f388d8 DB |
369 | ssize_t status; |
370 | ||
371 | mutex_lock(&sysfs_lock); | |
372 | ||
373 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
374 | status = -EIO; | |
375 | else if (!test_bit(FLAG_IS_OUT, &desc->flags)) | |
376 | status = -EPERM; | |
377 | else { | |
378 | long value; | |
379 | ||
a3d88c92 | 380 | status = kstrtol(buf, 0, &value); |
d8f388d8 | 381 | if (status == 0) { |
79a9becd | 382 | gpiod_set_value_cansleep(desc, value); |
d8f388d8 DB |
383 | status = size; |
384 | } | |
385 | } | |
386 | ||
387 | mutex_unlock(&sysfs_lock); | |
388 | return status; | |
389 | } | |
390 | ||
07697461 | 391 | static const DEVICE_ATTR(value, 0644, |
d8f388d8 DB |
392 | gpio_value_show, gpio_value_store); |
393 | ||
ff77c352 DG |
394 | static irqreturn_t gpio_sysfs_irq(int irq, void *priv) |
395 | { | |
5ba1821d | 396 | struct sysfs_dirent *value_sd = priv; |
ff77c352 | 397 | |
5ba1821d | 398 | sysfs_notify_dirent(value_sd); |
ff77c352 DG |
399 | return IRQ_HANDLED; |
400 | } | |
401 | ||
ff77c352 DG |
402 | static int gpio_setup_irq(struct gpio_desc *desc, struct device *dev, |
403 | unsigned long gpio_flags) | |
404 | { | |
5ba1821d | 405 | struct sysfs_dirent *value_sd; |
ff77c352 DG |
406 | unsigned long irq_flags; |
407 | int ret, irq, id; | |
408 | ||
409 | if ((desc->flags & GPIO_TRIGGER_MASK) == gpio_flags) | |
410 | return 0; | |
411 | ||
372e722e | 412 | irq = gpiod_to_irq(desc); |
ff77c352 DG |
413 | if (irq < 0) |
414 | return -EIO; | |
415 | ||
5ba1821d DG |
416 | id = desc->flags >> ID_SHIFT; |
417 | value_sd = idr_find(&dirent_idr, id); | |
418 | if (value_sd) | |
419 | free_irq(irq, value_sd); | |
ff77c352 DG |
420 | |
421 | desc->flags &= ~GPIO_TRIGGER_MASK; | |
422 | ||
423 | if (!gpio_flags) { | |
d468bf9e | 424 | gpiod_unlock_as_irq(desc); |
ff77c352 | 425 | ret = 0; |
5ba1821d | 426 | goto free_id; |
ff77c352 DG |
427 | } |
428 | ||
429 | irq_flags = IRQF_SHARED; | |
430 | if (test_bit(FLAG_TRIG_FALL, &gpio_flags)) | |
07697461 JN |
431 | irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? |
432 | IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING; | |
ff77c352 | 433 | if (test_bit(FLAG_TRIG_RISE, &gpio_flags)) |
07697461 JN |
434 | irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? |
435 | IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING; | |
ff77c352 | 436 | |
5ba1821d | 437 | if (!value_sd) { |
388975cc | 438 | value_sd = sysfs_get_dirent(dev->kobj.sd, "value"); |
5ba1821d DG |
439 | if (!value_sd) { |
440 | ret = -ENODEV; | |
ff77c352 DG |
441 | goto err_out; |
442 | } | |
443 | ||
62f516b8 TH |
444 | ret = idr_alloc(&dirent_idr, value_sd, 1, 0, GFP_KERNEL); |
445 | if (ret < 0) | |
5ba1821d | 446 | goto free_sd; |
62f516b8 | 447 | id = ret; |
ff77c352 DG |
448 | |
449 | desc->flags &= GPIO_FLAGS_MASK; | |
5ba1821d | 450 | desc->flags |= (unsigned long)id << ID_SHIFT; |
ff77c352 | 451 | |
5ba1821d | 452 | if (desc->flags >> ID_SHIFT != id) { |
ff77c352 DG |
453 | ret = -ERANGE; |
454 | goto free_id; | |
455 | } | |
ff77c352 DG |
456 | } |
457 | ||
364fadb3 | 458 | ret = request_any_context_irq(irq, gpio_sysfs_irq, irq_flags, |
5ba1821d | 459 | "gpiolib", value_sd); |
364fadb3 | 460 | if (ret < 0) |
5ba1821d | 461 | goto free_id; |
ff77c352 | 462 | |
d468bf9e LW |
463 | ret = gpiod_lock_as_irq(desc); |
464 | if (ret < 0) { | |
465 | gpiod_warn(desc, "failed to flag the GPIO for IRQ\n"); | |
466 | goto free_id; | |
467 | } | |
468 | ||
ff77c352 DG |
469 | desc->flags |= gpio_flags; |
470 | return 0; | |
471 | ||
ff77c352 | 472 | free_id: |
5ba1821d | 473 | idr_remove(&dirent_idr, id); |
ff77c352 | 474 | desc->flags &= GPIO_FLAGS_MASK; |
5ba1821d DG |
475 | free_sd: |
476 | if (value_sd) | |
477 | sysfs_put(value_sd); | |
ff77c352 DG |
478 | err_out: |
479 | return ret; | |
480 | } | |
481 | ||
482 | static const struct { | |
483 | const char *name; | |
484 | unsigned long flags; | |
485 | } trigger_types[] = { | |
486 | { "none", 0 }, | |
487 | { "falling", BIT(FLAG_TRIG_FALL) }, | |
488 | { "rising", BIT(FLAG_TRIG_RISE) }, | |
489 | { "both", BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE) }, | |
490 | }; | |
491 | ||
492 | static ssize_t gpio_edge_show(struct device *dev, | |
493 | struct device_attribute *attr, char *buf) | |
494 | { | |
495 | const struct gpio_desc *desc = dev_get_drvdata(dev); | |
496 | ssize_t status; | |
497 | ||
498 | mutex_lock(&sysfs_lock); | |
499 | ||
500 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
501 | status = -EIO; | |
502 | else { | |
503 | int i; | |
504 | ||
505 | status = 0; | |
506 | for (i = 0; i < ARRAY_SIZE(trigger_types); i++) | |
507 | if ((desc->flags & GPIO_TRIGGER_MASK) | |
508 | == trigger_types[i].flags) { | |
509 | status = sprintf(buf, "%s\n", | |
510 | trigger_types[i].name); | |
511 | break; | |
512 | } | |
513 | } | |
514 | ||
515 | mutex_unlock(&sysfs_lock); | |
516 | return status; | |
517 | } | |
518 | ||
519 | static ssize_t gpio_edge_store(struct device *dev, | |
520 | struct device_attribute *attr, const char *buf, size_t size) | |
521 | { | |
522 | struct gpio_desc *desc = dev_get_drvdata(dev); | |
523 | ssize_t status; | |
524 | int i; | |
525 | ||
526 | for (i = 0; i < ARRAY_SIZE(trigger_types); i++) | |
527 | if (sysfs_streq(trigger_types[i].name, buf)) | |
528 | goto found; | |
529 | return -EINVAL; | |
530 | ||
531 | found: | |
532 | mutex_lock(&sysfs_lock); | |
533 | ||
534 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
535 | status = -EIO; | |
536 | else { | |
537 | status = gpio_setup_irq(desc, dev, trigger_types[i].flags); | |
538 | if (!status) | |
539 | status = size; | |
540 | } | |
541 | ||
542 | mutex_unlock(&sysfs_lock); | |
543 | ||
544 | return status; | |
545 | } | |
546 | ||
547 | static DEVICE_ATTR(edge, 0644, gpio_edge_show, gpio_edge_store); | |
548 | ||
07697461 JN |
549 | static int sysfs_set_active_low(struct gpio_desc *desc, struct device *dev, |
550 | int value) | |
551 | { | |
552 | int status = 0; | |
553 | ||
554 | if (!!test_bit(FLAG_ACTIVE_LOW, &desc->flags) == !!value) | |
555 | return 0; | |
556 | ||
557 | if (value) | |
558 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
559 | else | |
560 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
561 | ||
562 | /* reconfigure poll(2) support if enabled on one edge only */ | |
563 | if (dev != NULL && (!!test_bit(FLAG_TRIG_RISE, &desc->flags) ^ | |
564 | !!test_bit(FLAG_TRIG_FALL, &desc->flags))) { | |
565 | unsigned long trigger_flags = desc->flags & GPIO_TRIGGER_MASK; | |
566 | ||
567 | gpio_setup_irq(desc, dev, 0); | |
568 | status = gpio_setup_irq(desc, dev, trigger_flags); | |
569 | } | |
570 | ||
571 | return status; | |
572 | } | |
573 | ||
574 | static ssize_t gpio_active_low_show(struct device *dev, | |
575 | struct device_attribute *attr, char *buf) | |
576 | { | |
577 | const struct gpio_desc *desc = dev_get_drvdata(dev); | |
578 | ssize_t status; | |
579 | ||
580 | mutex_lock(&sysfs_lock); | |
581 | ||
582 | if (!test_bit(FLAG_EXPORT, &desc->flags)) | |
583 | status = -EIO; | |
584 | else | |
585 | status = sprintf(buf, "%d\n", | |
586 | !!test_bit(FLAG_ACTIVE_LOW, &desc->flags)); | |
587 | ||
588 | mutex_unlock(&sysfs_lock); | |
589 | ||
590 | return status; | |
591 | } | |
592 | ||
593 | static ssize_t gpio_active_low_store(struct device *dev, | |
594 | struct device_attribute *attr, const char *buf, size_t size) | |
595 | { | |
596 | struct gpio_desc *desc = dev_get_drvdata(dev); | |
597 | ssize_t status; | |
598 | ||
599 | mutex_lock(&sysfs_lock); | |
600 | ||
601 | if (!test_bit(FLAG_EXPORT, &desc->flags)) { | |
602 | status = -EIO; | |
603 | } else { | |
604 | long value; | |
605 | ||
a3d88c92 | 606 | status = kstrtol(buf, 0, &value); |
07697461 JN |
607 | if (status == 0) |
608 | status = sysfs_set_active_low(desc, dev, value != 0); | |
609 | } | |
610 | ||
611 | mutex_unlock(&sysfs_lock); | |
612 | ||
613 | return status ? : size; | |
614 | } | |
615 | ||
616 | static const DEVICE_ATTR(active_low, 0644, | |
617 | gpio_active_low_show, gpio_active_low_store); | |
618 | ||
d8f388d8 | 619 | static const struct attribute *gpio_attrs[] = { |
d8f388d8 | 620 | &dev_attr_value.attr, |
07697461 | 621 | &dev_attr_active_low.attr, |
d8f388d8 DB |
622 | NULL, |
623 | }; | |
624 | ||
625 | static const struct attribute_group gpio_attr_group = { | |
626 | .attrs = (struct attribute **) gpio_attrs, | |
627 | }; | |
628 | ||
629 | /* | |
630 | * /sys/class/gpio/gpiochipN/ | |
631 | * /base ... matching gpio_chip.base (N) | |
632 | * /label ... matching gpio_chip.label | |
633 | * /ngpio ... matching gpio_chip.ngpio | |
634 | */ | |
635 | ||
636 | static ssize_t chip_base_show(struct device *dev, | |
637 | struct device_attribute *attr, char *buf) | |
638 | { | |
639 | const struct gpio_chip *chip = dev_get_drvdata(dev); | |
640 | ||
641 | return sprintf(buf, "%d\n", chip->base); | |
642 | } | |
643 | static DEVICE_ATTR(base, 0444, chip_base_show, NULL); | |
644 | ||
645 | static ssize_t chip_label_show(struct device *dev, | |
646 | struct device_attribute *attr, char *buf) | |
647 | { | |
648 | const struct gpio_chip *chip = dev_get_drvdata(dev); | |
649 | ||
650 | return sprintf(buf, "%s\n", chip->label ? : ""); | |
651 | } | |
652 | static DEVICE_ATTR(label, 0444, chip_label_show, NULL); | |
653 | ||
654 | static ssize_t chip_ngpio_show(struct device *dev, | |
655 | struct device_attribute *attr, char *buf) | |
656 | { | |
657 | const struct gpio_chip *chip = dev_get_drvdata(dev); | |
658 | ||
659 | return sprintf(buf, "%u\n", chip->ngpio); | |
660 | } | |
661 | static DEVICE_ATTR(ngpio, 0444, chip_ngpio_show, NULL); | |
662 | ||
663 | static const struct attribute *gpiochip_attrs[] = { | |
664 | &dev_attr_base.attr, | |
665 | &dev_attr_label.attr, | |
666 | &dev_attr_ngpio.attr, | |
667 | NULL, | |
668 | }; | |
669 | ||
670 | static const struct attribute_group gpiochip_attr_group = { | |
671 | .attrs = (struct attribute **) gpiochip_attrs, | |
672 | }; | |
673 | ||
674 | /* | |
675 | * /sys/class/gpio/export ... write-only | |
676 | * integer N ... number of GPIO to export (full access) | |
677 | * /sys/class/gpio/unexport ... write-only | |
678 | * integer N ... number of GPIO to unexport | |
679 | */ | |
28812fe1 AK |
680 | static ssize_t export_store(struct class *class, |
681 | struct class_attribute *attr, | |
682 | const char *buf, size_t len) | |
d8f388d8 | 683 | { |
372e722e AC |
684 | long gpio; |
685 | struct gpio_desc *desc; | |
686 | int status; | |
d8f388d8 | 687 | |
a3d88c92 | 688 | status = kstrtol(buf, 0, &gpio); |
d8f388d8 DB |
689 | if (status < 0) |
690 | goto done; | |
691 | ||
372e722e | 692 | desc = gpio_to_desc(gpio); |
bcabdef1 AC |
693 | /* reject invalid GPIOs */ |
694 | if (!desc) { | |
695 | pr_warn("%s: invalid GPIO %ld\n", __func__, gpio); | |
696 | return -EINVAL; | |
697 | } | |
372e722e | 698 | |
d8f388d8 DB |
699 | /* No extra locking here; FLAG_SYSFS just signifies that the |
700 | * request and export were done by on behalf of userspace, so | |
701 | * they may be undone on its behalf too. | |
702 | */ | |
703 | ||
372e722e | 704 | status = gpiod_request(desc, "sysfs"); |
ad2fab36 MN |
705 | if (status < 0) { |
706 | if (status == -EPROBE_DEFER) | |
707 | status = -ENODEV; | |
d8f388d8 | 708 | goto done; |
ad2fab36 | 709 | } |
372e722e | 710 | status = gpiod_export(desc, true); |
d8f388d8 | 711 | if (status < 0) |
372e722e | 712 | gpiod_free(desc); |
d8f388d8 | 713 | else |
372e722e | 714 | set_bit(FLAG_SYSFS, &desc->flags); |
d8f388d8 DB |
715 | |
716 | done: | |
717 | if (status) | |
718 | pr_debug("%s: status %d\n", __func__, status); | |
719 | return status ? : len; | |
720 | } | |
721 | ||
28812fe1 AK |
722 | static ssize_t unexport_store(struct class *class, |
723 | struct class_attribute *attr, | |
724 | const char *buf, size_t len) | |
d8f388d8 | 725 | { |
372e722e AC |
726 | long gpio; |
727 | struct gpio_desc *desc; | |
728 | int status; | |
d8f388d8 | 729 | |
a3d88c92 | 730 | status = kstrtol(buf, 0, &gpio); |
d8f388d8 DB |
731 | if (status < 0) |
732 | goto done; | |
733 | ||
372e722e | 734 | desc = gpio_to_desc(gpio); |
d8f388d8 | 735 | /* reject bogus commands (gpio_unexport ignores them) */ |
bcabdef1 AC |
736 | if (!desc) { |
737 | pr_warn("%s: invalid GPIO %ld\n", __func__, gpio); | |
738 | return -EINVAL; | |
739 | } | |
740 | ||
741 | status = -EINVAL; | |
d8f388d8 DB |
742 | |
743 | /* No extra locking here; FLAG_SYSFS just signifies that the | |
744 | * request and export were done by on behalf of userspace, so | |
745 | * they may be undone on its behalf too. | |
746 | */ | |
372e722e | 747 | if (test_and_clear_bit(FLAG_SYSFS, &desc->flags)) { |
d8f388d8 | 748 | status = 0; |
372e722e | 749 | gpiod_free(desc); |
d8f388d8 DB |
750 | } |
751 | done: | |
752 | if (status) | |
753 | pr_debug("%s: status %d\n", __func__, status); | |
754 | return status ? : len; | |
755 | } | |
756 | ||
757 | static struct class_attribute gpio_class_attrs[] = { | |
758 | __ATTR(export, 0200, NULL, export_store), | |
759 | __ATTR(unexport, 0200, NULL, unexport_store), | |
760 | __ATTR_NULL, | |
761 | }; | |
762 | ||
763 | static struct class gpio_class = { | |
764 | .name = "gpio", | |
765 | .owner = THIS_MODULE, | |
766 | ||
767 | .class_attrs = gpio_class_attrs, | |
768 | }; | |
769 | ||
770 | ||
771 | /** | |
79a9becd | 772 | * gpiod_export - export a GPIO through sysfs |
d8f388d8 DB |
773 | * @gpio: gpio to make available, already requested |
774 | * @direction_may_change: true if userspace may change gpio direction | |
775 | * Context: arch_initcall or later | |
776 | * | |
777 | * When drivers want to make a GPIO accessible to userspace after they | |
778 | * have requested it -- perhaps while debugging, or as part of their | |
779 | * public interface -- they may use this routine. If the GPIO can | |
780 | * change direction (some can't) and the caller allows it, userspace | |
781 | * will see "direction" sysfs attribute which may be used to change | |
782 | * the gpio's direction. A "value" attribute will always be provided. | |
783 | * | |
784 | * Returns zero on success, else an error. | |
785 | */ | |
79a9becd | 786 | int gpiod_export(struct gpio_desc *desc, bool direction_may_change) |
d8f388d8 DB |
787 | { |
788 | unsigned long flags; | |
fc4e2514 | 789 | int status; |
62154991 | 790 | const char *ioname = NULL; |
fc4e2514 | 791 | struct device *dev; |
372e722e | 792 | int offset; |
d8f388d8 DB |
793 | |
794 | /* can't export until sysfs is available ... */ | |
795 | if (!gpio_class.p) { | |
796 | pr_debug("%s: called too early!\n", __func__); | |
797 | return -ENOENT; | |
798 | } | |
799 | ||
372e722e AC |
800 | if (!desc) { |
801 | pr_debug("%s: invalid gpio descriptor\n", __func__); | |
fc4e2514 RM |
802 | return -EINVAL; |
803 | } | |
d8f388d8 DB |
804 | |
805 | mutex_lock(&sysfs_lock); | |
806 | ||
807 | spin_lock_irqsave(&gpio_lock, flags); | |
fc4e2514 RM |
808 | if (!test_bit(FLAG_REQUESTED, &desc->flags) || |
809 | test_bit(FLAG_EXPORT, &desc->flags)) { | |
810 | spin_unlock_irqrestore(&gpio_lock, flags); | |
811 | pr_debug("%s: gpio %d unavailable (requested=%d, exported=%d)\n", | |
372e722e | 812 | __func__, desc_to_gpio(desc), |
fc4e2514 RM |
813 | test_bit(FLAG_REQUESTED, &desc->flags), |
814 | test_bit(FLAG_EXPORT, &desc->flags)); | |
529f2ad5 DC |
815 | status = -EPERM; |
816 | goto fail_unlock; | |
d8f388d8 | 817 | } |
fc4e2514 RM |
818 | |
819 | if (!desc->chip->direction_input || !desc->chip->direction_output) | |
820 | direction_may_change = false; | |
d8f388d8 DB |
821 | spin_unlock_irqrestore(&gpio_lock, flags); |
822 | ||
372e722e AC |
823 | offset = gpio_chip_hwgpio(desc); |
824 | if (desc->chip->names && desc->chip->names[offset]) | |
825 | ioname = desc->chip->names[offset]; | |
926b663c | 826 | |
fc4e2514 | 827 | dev = device_create(&gpio_class, desc->chip->dev, MKDEV(0, 0), |
372e722e AC |
828 | desc, ioname ? ioname : "gpio%u", |
829 | desc_to_gpio(desc)); | |
fc4e2514 RM |
830 | if (IS_ERR(dev)) { |
831 | status = PTR_ERR(dev); | |
832 | goto fail_unlock; | |
d8f388d8 DB |
833 | } |
834 | ||
fc4e2514 | 835 | status = sysfs_create_group(&dev->kobj, &gpio_attr_group); |
d8f388d8 | 836 | if (status) |
fc4e2514 | 837 | goto fail_unregister_device; |
d8f388d8 | 838 | |
fc4e2514 RM |
839 | if (direction_may_change) { |
840 | status = device_create_file(dev, &dev_attr_direction); | |
841 | if (status) | |
842 | goto fail_unregister_device; | |
843 | } | |
844 | ||
372e722e | 845 | if (gpiod_to_irq(desc) >= 0 && (direction_may_change || |
fc4e2514 RM |
846 | !test_bit(FLAG_IS_OUT, &desc->flags))) { |
847 | status = device_create_file(dev, &dev_attr_edge); | |
848 | if (status) | |
849 | goto fail_unregister_device; | |
850 | } | |
d8f388d8 | 851 | |
fc4e2514 RM |
852 | set_bit(FLAG_EXPORT, &desc->flags); |
853 | mutex_unlock(&sysfs_lock); | |
854 | return 0; | |
855 | ||
856 | fail_unregister_device: | |
857 | device_unregister(dev); | |
858 | fail_unlock: | |
859 | mutex_unlock(&sysfs_lock); | |
372e722e AC |
860 | pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc), |
861 | status); | |
d8f388d8 DB |
862 | return status; |
863 | } | |
79a9becd | 864 | EXPORT_SYMBOL_GPL(gpiod_export); |
d8f388d8 | 865 | |
9f3b795a | 866 | static int match_export(struct device *dev, const void *data) |
d8f388d8 DB |
867 | { |
868 | return dev_get_drvdata(dev) == data; | |
869 | } | |
870 | ||
a4177ee7 | 871 | /** |
79a9becd | 872 | * gpiod_export_link - create a sysfs link to an exported GPIO node |
a4177ee7 JN |
873 | * @dev: device under which to create symlink |
874 | * @name: name of the symlink | |
875 | * @gpio: gpio to create symlink to, already exported | |
876 | * | |
877 | * Set up a symlink from /sys/.../dev/name to /sys/class/gpio/gpioN | |
878 | * node. Caller is responsible for unlinking. | |
879 | * | |
880 | * Returns zero on success, else an error. | |
881 | */ | |
79a9becd AC |
882 | int gpiod_export_link(struct device *dev, const char *name, |
883 | struct gpio_desc *desc) | |
a4177ee7 | 884 | { |
a4177ee7 JN |
885 | int status = -EINVAL; |
886 | ||
bcabdef1 AC |
887 | if (!desc) { |
888 | pr_warn("%s: invalid GPIO\n", __func__); | |
889 | return -EINVAL; | |
890 | } | |
a4177ee7 JN |
891 | |
892 | mutex_lock(&sysfs_lock); | |
893 | ||
a4177ee7 JN |
894 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
895 | struct device *tdev; | |
896 | ||
897 | tdev = class_find_device(&gpio_class, NULL, desc, match_export); | |
898 | if (tdev != NULL) { | |
899 | status = sysfs_create_link(&dev->kobj, &tdev->kobj, | |
900 | name); | |
901 | } else { | |
902 | status = -ENODEV; | |
903 | } | |
904 | } | |
905 | ||
906 | mutex_unlock(&sysfs_lock); | |
907 | ||
a4177ee7 | 908 | if (status) |
372e722e AC |
909 | pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc), |
910 | status); | |
a4177ee7 JN |
911 | |
912 | return status; | |
913 | } | |
79a9becd | 914 | EXPORT_SYMBOL_GPL(gpiod_export_link); |
07697461 JN |
915 | |
916 | /** | |
79a9becd | 917 | * gpiod_sysfs_set_active_low - set the polarity of gpio sysfs value |
07697461 JN |
918 | * @gpio: gpio to change |
919 | * @value: non-zero to use active low, i.e. inverted values | |
920 | * | |
921 | * Set the polarity of /sys/class/gpio/gpioN/value sysfs attribute. | |
922 | * The GPIO does not have to be exported yet. If poll(2) support has | |
923 | * been enabled for either rising or falling edge, it will be | |
924 | * reconfigured to follow the new polarity. | |
925 | * | |
926 | * Returns zero on success, else an error. | |
927 | */ | |
79a9becd | 928 | int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value) |
07697461 | 929 | { |
07697461 JN |
930 | struct device *dev = NULL; |
931 | int status = -EINVAL; | |
932 | ||
bcabdef1 AC |
933 | if (!desc) { |
934 | pr_warn("%s: invalid GPIO\n", __func__); | |
935 | return -EINVAL; | |
936 | } | |
07697461 JN |
937 | |
938 | mutex_lock(&sysfs_lock); | |
939 | ||
07697461 | 940 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
07697461 JN |
941 | dev = class_find_device(&gpio_class, NULL, desc, match_export); |
942 | if (dev == NULL) { | |
943 | status = -ENODEV; | |
944 | goto unlock; | |
945 | } | |
946 | } | |
947 | ||
948 | status = sysfs_set_active_low(desc, dev, value); | |
949 | ||
950 | unlock: | |
951 | mutex_unlock(&sysfs_lock); | |
952 | ||
07697461 | 953 | if (status) |
372e722e AC |
954 | pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc), |
955 | status); | |
07697461 JN |
956 | |
957 | return status; | |
958 | } | |
79a9becd | 959 | EXPORT_SYMBOL_GPL(gpiod_sysfs_set_active_low); |
07697461 | 960 | |
d8f388d8 | 961 | /** |
79a9becd | 962 | * gpiod_unexport - reverse effect of gpio_export() |
d8f388d8 DB |
963 | * @gpio: gpio to make unavailable |
964 | * | |
965 | * This is implicit on gpio_free(). | |
966 | */ | |
79a9becd | 967 | void gpiod_unexport(struct gpio_desc *desc) |
d8f388d8 | 968 | { |
6a99ad4a | 969 | int status = 0; |
864533ce | 970 | struct device *dev = NULL; |
d8f388d8 | 971 | |
372e722e | 972 | if (!desc) { |
bcabdef1 AC |
973 | pr_warn("%s: invalid GPIO\n", __func__); |
974 | return; | |
6a99ad4a | 975 | } |
d8f388d8 DB |
976 | |
977 | mutex_lock(&sysfs_lock); | |
978 | ||
d8f388d8 | 979 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
d8f388d8 DB |
980 | |
981 | dev = class_find_device(&gpio_class, NULL, desc, match_export); | |
982 | if (dev) { | |
ff77c352 | 983 | gpio_setup_irq(desc, dev, 0); |
d8f388d8 | 984 | clear_bit(FLAG_EXPORT, &desc->flags); |
d8f388d8 DB |
985 | } else |
986 | status = -ENODEV; | |
987 | } | |
988 | ||
989 | mutex_unlock(&sysfs_lock); | |
372e722e | 990 | |
864533ce ML |
991 | if (dev) { |
992 | device_unregister(dev); | |
993 | put_device(dev); | |
994 | } | |
bcabdef1 | 995 | |
d8f388d8 | 996 | if (status) |
372e722e AC |
997 | pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc), |
998 | status); | |
999 | } | |
79a9becd | 1000 | EXPORT_SYMBOL_GPL(gpiod_unexport); |
d8f388d8 DB |
1001 | |
1002 | static int gpiochip_export(struct gpio_chip *chip) | |
1003 | { | |
1004 | int status; | |
1005 | struct device *dev; | |
1006 | ||
1007 | /* Many systems register gpio chips for SOC support very early, | |
1008 | * before driver model support is available. In those cases we | |
1009 | * export this later, in gpiolib_sysfs_init() ... here we just | |
1010 | * verify that _some_ field of gpio_class got initialized. | |
1011 | */ | |
1012 | if (!gpio_class.p) | |
1013 | return 0; | |
1014 | ||
1015 | /* use chip->base for the ID; it's already known to be unique */ | |
1016 | mutex_lock(&sysfs_lock); | |
1017 | dev = device_create(&gpio_class, chip->dev, MKDEV(0, 0), chip, | |
1018 | "gpiochip%d", chip->base); | |
d62668e1 | 1019 | if (!IS_ERR(dev)) { |
d8f388d8 DB |
1020 | status = sysfs_create_group(&dev->kobj, |
1021 | &gpiochip_attr_group); | |
1022 | } else | |
d62668e1 | 1023 | status = PTR_ERR(dev); |
d8f388d8 DB |
1024 | chip->exported = (status == 0); |
1025 | mutex_unlock(&sysfs_lock); | |
1026 | ||
1027 | if (status) { | |
1028 | unsigned long flags; | |
1029 | unsigned gpio; | |
1030 | ||
1031 | spin_lock_irqsave(&gpio_lock, flags); | |
6c0b4e6c AC |
1032 | gpio = 0; |
1033 | while (gpio < chip->ngpio) | |
1034 | chip->desc[gpio++].chip = NULL; | |
d8f388d8 DB |
1035 | spin_unlock_irqrestore(&gpio_lock, flags); |
1036 | ||
1037 | pr_debug("%s: chip %s status %d\n", __func__, | |
1038 | chip->label, status); | |
1039 | } | |
1040 | ||
1041 | return status; | |
1042 | } | |
1043 | ||
1044 | static void gpiochip_unexport(struct gpio_chip *chip) | |
1045 | { | |
1046 | int status; | |
1047 | struct device *dev; | |
1048 | ||
1049 | mutex_lock(&sysfs_lock); | |
1050 | dev = class_find_device(&gpio_class, NULL, chip, match_export); | |
1051 | if (dev) { | |
1052 | put_device(dev); | |
1053 | device_unregister(dev); | |
1054 | chip->exported = 0; | |
1055 | status = 0; | |
1056 | } else | |
1057 | status = -ENODEV; | |
1058 | mutex_unlock(&sysfs_lock); | |
1059 | ||
1060 | if (status) | |
1061 | pr_debug("%s: chip %s status %d\n", __func__, | |
1062 | chip->label, status); | |
1063 | } | |
1064 | ||
1065 | static int __init gpiolib_sysfs_init(void) | |
1066 | { | |
1067 | int status; | |
1068 | unsigned long flags; | |
65493e3a | 1069 | struct gpio_chip *chip; |
d8f388d8 DB |
1070 | |
1071 | status = class_register(&gpio_class); | |
1072 | if (status < 0) | |
1073 | return status; | |
1074 | ||
1075 | /* Scan and register the gpio_chips which registered very | |
1076 | * early (e.g. before the class_register above was called). | |
1077 | * | |
1078 | * We run before arch_initcall() so chip->dev nodes can have | |
1079 | * registered, and so arch_initcall() can always gpio_export(). | |
1080 | */ | |
1081 | spin_lock_irqsave(&gpio_lock, flags); | |
65493e3a | 1082 | list_for_each_entry(chip, &gpio_chips, list) { |
d8f388d8 DB |
1083 | if (!chip || chip->exported) |
1084 | continue; | |
1085 | ||
1086 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1087 | status = gpiochip_export(chip); | |
1088 | spin_lock_irqsave(&gpio_lock, flags); | |
1089 | } | |
1090 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1091 | ||
1092 | ||
1093 | return status; | |
1094 | } | |
1095 | postcore_initcall(gpiolib_sysfs_init); | |
1096 | ||
1097 | #else | |
1098 | static inline int gpiochip_export(struct gpio_chip *chip) | |
1099 | { | |
1100 | return 0; | |
1101 | } | |
1102 | ||
1103 | static inline void gpiochip_unexport(struct gpio_chip *chip) | |
1104 | { | |
1105 | } | |
1106 | ||
1107 | #endif /* CONFIG_GPIO_SYSFS */ | |
1108 | ||
1a989d0f AC |
1109 | /* |
1110 | * Add a new chip to the global chips list, keeping the list of chips sorted | |
1111 | * by base order. | |
1112 | * | |
1113 | * Return -EBUSY if the new chip overlaps with some other chip's integer | |
1114 | * space. | |
1115 | */ | |
1116 | static int gpiochip_add_to_list(struct gpio_chip *chip) | |
1117 | { | |
1118 | struct list_head *pos = &gpio_chips; | |
1119 | struct gpio_chip *_chip; | |
1120 | int err = 0; | |
1121 | ||
1122 | /* find where to insert our chip */ | |
1123 | list_for_each(pos, &gpio_chips) { | |
1124 | _chip = list_entry(pos, struct gpio_chip, list); | |
1125 | /* shall we insert before _chip? */ | |
1126 | if (_chip->base >= chip->base + chip->ngpio) | |
1127 | break; | |
1128 | } | |
1129 | ||
1130 | /* are we stepping on the chip right before? */ | |
1131 | if (pos != &gpio_chips && pos->prev != &gpio_chips) { | |
1132 | _chip = list_entry(pos->prev, struct gpio_chip, list); | |
1133 | if (_chip->base + _chip->ngpio > chip->base) { | |
1134 | dev_err(chip->dev, | |
1135 | "GPIO integer space overlap, cannot add chip\n"); | |
1136 | err = -EBUSY; | |
1137 | } | |
1138 | } | |
1139 | ||
1140 | if (!err) | |
1141 | list_add_tail(&chip->list, pos); | |
1142 | ||
1143 | return err; | |
1144 | } | |
1145 | ||
d2876d08 DB |
1146 | /** |
1147 | * gpiochip_add() - register a gpio_chip | |
1148 | * @chip: the chip to register, with chip->base initialized | |
1149 | * Context: potentially before irqs or kmalloc will work | |
1150 | * | |
1151 | * Returns a negative errno if the chip can't be registered, such as | |
1152 | * because the chip->base is invalid or already associated with a | |
1153 | * different chip. Otherwise it returns zero as a success code. | |
8d0aab2f | 1154 | * |
d8f388d8 DB |
1155 | * When gpiochip_add() is called very early during boot, so that GPIOs |
1156 | * can be freely used, the chip->dev device must be registered before | |
1157 | * the gpio framework's arch_initcall(). Otherwise sysfs initialization | |
1158 | * for GPIOs will fail rudely. | |
1159 | * | |
8d0aab2f AV |
1160 | * If chip->base is negative, this requests dynamic assignment of |
1161 | * a range of valid GPIOs. | |
d2876d08 DB |
1162 | */ |
1163 | int gpiochip_add(struct gpio_chip *chip) | |
1164 | { | |
1165 | unsigned long flags; | |
1166 | int status = 0; | |
1167 | unsigned id; | |
8d0aab2f | 1168 | int base = chip->base; |
d2876d08 | 1169 | |
bff5fda9 | 1170 | if ((!gpio_is_valid(base) || !gpio_is_valid(base + chip->ngpio - 1)) |
8d0aab2f | 1171 | && base >= 0) { |
d2876d08 DB |
1172 | status = -EINVAL; |
1173 | goto fail; | |
1174 | } | |
1175 | ||
1176 | spin_lock_irqsave(&gpio_lock, flags); | |
1177 | ||
8d0aab2f AV |
1178 | if (base < 0) { |
1179 | base = gpiochip_find_base(chip->ngpio); | |
1180 | if (base < 0) { | |
1181 | status = base; | |
d8f388d8 | 1182 | goto unlock; |
8d0aab2f AV |
1183 | } |
1184 | chip->base = base; | |
1185 | } | |
1186 | ||
1a989d0f AC |
1187 | status = gpiochip_add_to_list(chip); |
1188 | ||
d2876d08 | 1189 | if (status == 0) { |
6c0b4e6c AC |
1190 | chip->desc = &gpio_desc[chip->base]; |
1191 | ||
1192 | for (id = 0; id < chip->ngpio; id++) { | |
1193 | struct gpio_desc *desc = &chip->desc[id]; | |
1194 | desc->chip = chip; | |
d8f388d8 DB |
1195 | |
1196 | /* REVISIT: most hardware initializes GPIOs as | |
1197 | * inputs (often with pullups enabled) so power | |
1198 | * usage is minimized. Linux code should set the | |
1199 | * gpio direction first thing; but until it does, | |
80b0a602 | 1200 | * and in case chip->get_direction is not set, |
d8f388d8 DB |
1201 | * we may expose the wrong direction in sysfs. |
1202 | */ | |
6c0b4e6c | 1203 | desc->flags = !chip->direction_input |
d8f388d8 DB |
1204 | ? (1 << FLAG_IS_OUT) |
1205 | : 0; | |
d2876d08 DB |
1206 | } |
1207 | } | |
1208 | ||
3bae4811 ZG |
1209 | spin_unlock_irqrestore(&gpio_lock, flags); |
1210 | ||
f23f1516 SH |
1211 | #ifdef CONFIG_PINCTRL |
1212 | INIT_LIST_HEAD(&chip->pin_ranges); | |
1213 | #endif | |
1214 | ||
391c970c AV |
1215 | of_gpiochip_add(chip); |
1216 | ||
cedb1881 AV |
1217 | if (status) |
1218 | goto fail; | |
1219 | ||
1220 | status = gpiochip_export(chip); | |
1221 | if (status) | |
1222 | goto fail; | |
1223 | ||
ee1c1e7d | 1224 | pr_debug("gpiochip_add: registered GPIOs %d to %d on device: %s\n", |
64842aad GL |
1225 | chip->base, chip->base + chip->ngpio - 1, |
1226 | chip->label ? : "generic"); | |
1227 | ||
cedb1881 | 1228 | return 0; |
3bae4811 ZG |
1229 | |
1230 | unlock: | |
1231 | spin_unlock_irqrestore(&gpio_lock, flags); | |
d2876d08 DB |
1232 | fail: |
1233 | /* failures here can mean systems won't boot... */ | |
cedb1881 AV |
1234 | pr_err("gpiochip_add: gpios %d..%d (%s) failed to register\n", |
1235 | chip->base, chip->base + chip->ngpio - 1, | |
1236 | chip->label ? : "generic"); | |
d2876d08 DB |
1237 | return status; |
1238 | } | |
1239 | EXPORT_SYMBOL_GPL(gpiochip_add); | |
1240 | ||
1241 | /** | |
1242 | * gpiochip_remove() - unregister a gpio_chip | |
1243 | * @chip: the chip to unregister | |
1244 | * | |
1245 | * A gpio_chip with any GPIOs still requested may not be removed. | |
1246 | */ | |
1247 | int gpiochip_remove(struct gpio_chip *chip) | |
1248 | { | |
1249 | unsigned long flags; | |
1250 | int status = 0; | |
1251 | unsigned id; | |
1252 | ||
1253 | spin_lock_irqsave(&gpio_lock, flags); | |
1254 | ||
9ef0d6f7 | 1255 | gpiochip_remove_pin_ranges(chip); |
391c970c AV |
1256 | of_gpiochip_remove(chip); |
1257 | ||
6c0b4e6c AC |
1258 | for (id = 0; id < chip->ngpio; id++) { |
1259 | if (test_bit(FLAG_REQUESTED, &chip->desc[id].flags)) { | |
d2876d08 DB |
1260 | status = -EBUSY; |
1261 | break; | |
1262 | } | |
1263 | } | |
1264 | if (status == 0) { | |
6c0b4e6c AC |
1265 | for (id = 0; id < chip->ngpio; id++) |
1266 | chip->desc[id].chip = NULL; | |
1a989d0f AC |
1267 | |
1268 | list_del(&chip->list); | |
d2876d08 DB |
1269 | } |
1270 | ||
1271 | spin_unlock_irqrestore(&gpio_lock, flags); | |
d8f388d8 DB |
1272 | |
1273 | if (status == 0) | |
1274 | gpiochip_unexport(chip); | |
1275 | ||
d2876d08 DB |
1276 | return status; |
1277 | } | |
1278 | EXPORT_SYMBOL_GPL(gpiochip_remove); | |
1279 | ||
594fa265 GL |
1280 | /** |
1281 | * gpiochip_find() - iterator for locating a specific gpio_chip | |
1282 | * @data: data to pass to match function | |
1283 | * @callback: Callback function to check gpio_chip | |
1284 | * | |
1285 | * Similar to bus_find_device. It returns a reference to a gpio_chip as | |
1286 | * determined by a user supplied @match callback. The callback should return | |
1287 | * 0 if the device doesn't match and non-zero if it does. If the callback is | |
1288 | * non-zero, this function will return to the caller and not iterate over any | |
1289 | * more gpio_chips. | |
1290 | */ | |
07ce8ec7 | 1291 | struct gpio_chip *gpiochip_find(void *data, |
6e2cf651 | 1292 | int (*match)(struct gpio_chip *chip, |
3d0f7cf0 | 1293 | void *data)) |
594fa265 | 1294 | { |
125eef96 | 1295 | struct gpio_chip *chip; |
594fa265 | 1296 | unsigned long flags; |
594fa265 GL |
1297 | |
1298 | spin_lock_irqsave(&gpio_lock, flags); | |
125eef96 AC |
1299 | list_for_each_entry(chip, &gpio_chips, list) |
1300 | if (match(chip, data)) | |
594fa265 | 1301 | break; |
125eef96 AC |
1302 | |
1303 | /* No match? */ | |
1304 | if (&chip->list == &gpio_chips) | |
1305 | chip = NULL; | |
594fa265 GL |
1306 | spin_unlock_irqrestore(&gpio_lock, flags); |
1307 | ||
1308 | return chip; | |
1309 | } | |
8fa0c9bf | 1310 | EXPORT_SYMBOL_GPL(gpiochip_find); |
d2876d08 | 1311 | |
79697ef9 AC |
1312 | static int gpiochip_match_name(struct gpio_chip *chip, void *data) |
1313 | { | |
1314 | const char *name = data; | |
1315 | ||
1316 | return !strcmp(chip->label, name); | |
1317 | } | |
1318 | ||
1319 | static struct gpio_chip *find_chip_by_name(const char *name) | |
1320 | { | |
1321 | return gpiochip_find((void *)name, gpiochip_match_name); | |
1322 | } | |
1323 | ||
f23f1516 | 1324 | #ifdef CONFIG_PINCTRL |
165adc9c | 1325 | |
586a87e6 CR |
1326 | /** |
1327 | * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping | |
1328 | * @chip: the gpiochip to add the range for | |
1329 | * @pinctrl: the dev_name() of the pin controller to map to | |
1330 | * @gpio_offset: the start offset in the current gpio_chip number space | |
1331 | * @pin_group: name of the pin group inside the pin controller | |
1332 | */ | |
1333 | int gpiochip_add_pingroup_range(struct gpio_chip *chip, | |
1334 | struct pinctrl_dev *pctldev, | |
1335 | unsigned int gpio_offset, const char *pin_group) | |
1336 | { | |
1337 | struct gpio_pin_range *pin_range; | |
1338 | int ret; | |
1339 | ||
1340 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); | |
1341 | if (!pin_range) { | |
1342 | pr_err("%s: GPIO chip: failed to allocate pin ranges\n", | |
1343 | chip->label); | |
1344 | return -ENOMEM; | |
1345 | } | |
1346 | ||
1347 | /* Use local offset as range ID */ | |
1348 | pin_range->range.id = gpio_offset; | |
1349 | pin_range->range.gc = chip; | |
1350 | pin_range->range.name = chip->label; | |
1351 | pin_range->range.base = chip->base + gpio_offset; | |
1352 | pin_range->pctldev = pctldev; | |
1353 | ||
1354 | ret = pinctrl_get_group_pins(pctldev, pin_group, | |
1355 | &pin_range->range.pins, | |
1356 | &pin_range->range.npins); | |
61c6375d MN |
1357 | if (ret < 0) { |
1358 | kfree(pin_range); | |
586a87e6 | 1359 | return ret; |
61c6375d | 1360 | } |
586a87e6 CR |
1361 | |
1362 | pinctrl_add_gpio_range(pctldev, &pin_range->range); | |
1363 | ||
1364 | pr_debug("GPIO chip %s: created GPIO range %d->%d ==> %s PINGRP %s\n", | |
1365 | chip->label, gpio_offset, | |
1366 | gpio_offset + pin_range->range.npins - 1, | |
1367 | pinctrl_dev_get_devname(pctldev), pin_group); | |
1368 | ||
1369 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
1370 | ||
1371 | return 0; | |
1372 | } | |
1373 | EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); | |
1374 | ||
3f0f8670 LW |
1375 | /** |
1376 | * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping | |
1377 | * @chip: the gpiochip to add the range for | |
1378 | * @pinctrl_name: the dev_name() of the pin controller to map to | |
316511c0 LW |
1379 | * @gpio_offset: the start offset in the current gpio_chip number space |
1380 | * @pin_offset: the start offset in the pin controller number space | |
3f0f8670 LW |
1381 | * @npins: the number of pins from the offset of each pin space (GPIO and |
1382 | * pin controller) to accumulate in this range | |
1383 | */ | |
1e63d7b9 | 1384 | int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, |
316511c0 | 1385 | unsigned int gpio_offset, unsigned int pin_offset, |
3f0f8670 | 1386 | unsigned int npins) |
f23f1516 SH |
1387 | { |
1388 | struct gpio_pin_range *pin_range; | |
b4d4b1f0 | 1389 | int ret; |
f23f1516 | 1390 | |
3f0f8670 | 1391 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); |
f23f1516 SH |
1392 | if (!pin_range) { |
1393 | pr_err("%s: GPIO chip: failed to allocate pin ranges\n", | |
1394 | chip->label); | |
1e63d7b9 | 1395 | return -ENOMEM; |
f23f1516 SH |
1396 | } |
1397 | ||
3f0f8670 | 1398 | /* Use local offset as range ID */ |
316511c0 | 1399 | pin_range->range.id = gpio_offset; |
3f0f8670 | 1400 | pin_range->range.gc = chip; |
f23f1516 | 1401 | pin_range->range.name = chip->label; |
316511c0 LW |
1402 | pin_range->range.base = chip->base + gpio_offset; |
1403 | pin_range->range.pin_base = pin_offset; | |
f23f1516 | 1404 | pin_range->range.npins = npins; |
192c369c | 1405 | pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, |
f23f1516 | 1406 | &pin_range->range); |
8f23ca1a | 1407 | if (IS_ERR(pin_range->pctldev)) { |
b4d4b1f0 | 1408 | ret = PTR_ERR(pin_range->pctldev); |
3f0f8670 LW |
1409 | pr_err("%s: GPIO chip: could not create pin range\n", |
1410 | chip->label); | |
1411 | kfree(pin_range); | |
b4d4b1f0 | 1412 | return ret; |
3f0f8670 | 1413 | } |
316511c0 LW |
1414 | pr_debug("GPIO chip %s: created GPIO range %d->%d ==> %s PIN %d->%d\n", |
1415 | chip->label, gpio_offset, gpio_offset + npins - 1, | |
1416 | pinctl_name, | |
1417 | pin_offset, pin_offset + npins - 1); | |
f23f1516 SH |
1418 | |
1419 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
1e63d7b9 LW |
1420 | |
1421 | return 0; | |
f23f1516 | 1422 | } |
165adc9c | 1423 | EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); |
f23f1516 | 1424 | |
3f0f8670 LW |
1425 | /** |
1426 | * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings | |
1427 | * @chip: the chip to remove all the mappings for | |
1428 | */ | |
f23f1516 SH |
1429 | void gpiochip_remove_pin_ranges(struct gpio_chip *chip) |
1430 | { | |
1431 | struct gpio_pin_range *pin_range, *tmp; | |
1432 | ||
1433 | list_for_each_entry_safe(pin_range, tmp, &chip->pin_ranges, node) { | |
1434 | list_del(&pin_range->node); | |
1435 | pinctrl_remove_gpio_range(pin_range->pctldev, | |
1436 | &pin_range->range); | |
3f0f8670 | 1437 | kfree(pin_range); |
f23f1516 SH |
1438 | } |
1439 | } | |
165adc9c LW |
1440 | EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); |
1441 | ||
1442 | #endif /* CONFIG_PINCTRL */ | |
f23f1516 | 1443 | |
d2876d08 DB |
1444 | /* These "optional" allocation calls help prevent drivers from stomping |
1445 | * on each other, and help provide better diagnostics in debugfs. | |
1446 | * They're called even less than the "set direction" calls. | |
1447 | */ | |
372e722e | 1448 | static int gpiod_request(struct gpio_desc *desc, const char *label) |
d2876d08 | 1449 | { |
35e8bb51 | 1450 | struct gpio_chip *chip; |
e9354576 | 1451 | int status = -EPROBE_DEFER; |
d2876d08 DB |
1452 | unsigned long flags; |
1453 | ||
0204df47 | 1454 | if (!desc) { |
bcabdef1 AC |
1455 | pr_warn("%s: invalid GPIO\n", __func__); |
1456 | return -EINVAL; | |
ad2fab36 | 1457 | } |
bcabdef1 AC |
1458 | |
1459 | spin_lock_irqsave(&gpio_lock, flags); | |
1460 | ||
35e8bb51 | 1461 | chip = desc->chip; |
0204df47 AC |
1462 | if (chip == NULL) |
1463 | goto done; | |
d2876d08 | 1464 | |
35e8bb51 | 1465 | if (!try_module_get(chip->owner)) |
438d8908 GL |
1466 | goto done; |
1467 | ||
d2876d08 | 1468 | /* NOTE: gpio_request() can be called in early boot, |
35e8bb51 | 1469 | * before IRQs are enabled, for non-sleeping (SOC) GPIOs. |
d2876d08 DB |
1470 | */ |
1471 | ||
1472 | if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { | |
1473 | desc_set_label(desc, label ? : "?"); | |
1474 | status = 0; | |
438d8908 | 1475 | } else { |
d2876d08 | 1476 | status = -EBUSY; |
35e8bb51 | 1477 | module_put(chip->owner); |
7460db56 | 1478 | goto done; |
35e8bb51 DB |
1479 | } |
1480 | ||
1481 | if (chip->request) { | |
1482 | /* chip->request may sleep */ | |
1483 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 1484 | status = chip->request(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
1485 | spin_lock_irqsave(&gpio_lock, flags); |
1486 | ||
1487 | if (status < 0) { | |
1488 | desc_set_label(desc, NULL); | |
1489 | module_put(chip->owner); | |
1490 | clear_bit(FLAG_REQUESTED, &desc->flags); | |
80b0a602 | 1491 | goto done; |
35e8bb51 | 1492 | } |
438d8908 | 1493 | } |
80b0a602 MN |
1494 | if (chip->get_direction) { |
1495 | /* chip->get_direction may sleep */ | |
1496 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 1497 | gpiod_get_direction(desc); |
80b0a602 MN |
1498 | spin_lock_irqsave(&gpio_lock, flags); |
1499 | } | |
d2876d08 DB |
1500 | done: |
1501 | if (status) | |
372e722e | 1502 | pr_debug("_gpio_request: gpio-%d (%s) status %d\n", |
bcabdef1 | 1503 | desc_to_gpio(desc), label ? : "?", status); |
d2876d08 DB |
1504 | spin_unlock_irqrestore(&gpio_lock, flags); |
1505 | return status; | |
1506 | } | |
372e722e AC |
1507 | |
1508 | int gpio_request(unsigned gpio, const char *label) | |
1509 | { | |
1510 | return gpiod_request(gpio_to_desc(gpio), label); | |
1511 | } | |
d2876d08 DB |
1512 | EXPORT_SYMBOL_GPL(gpio_request); |
1513 | ||
372e722e | 1514 | static void gpiod_free(struct gpio_desc *desc) |
d2876d08 DB |
1515 | { |
1516 | unsigned long flags; | |
35e8bb51 | 1517 | struct gpio_chip *chip; |
d2876d08 | 1518 | |
3d599d1c UKK |
1519 | might_sleep(); |
1520 | ||
372e722e | 1521 | if (!desc) { |
d2876d08 DB |
1522 | WARN_ON(extra_checks); |
1523 | return; | |
1524 | } | |
1525 | ||
372e722e | 1526 | gpiod_unexport(desc); |
d8f388d8 | 1527 | |
d2876d08 DB |
1528 | spin_lock_irqsave(&gpio_lock, flags); |
1529 | ||
35e8bb51 DB |
1530 | chip = desc->chip; |
1531 | if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { | |
1532 | if (chip->free) { | |
1533 | spin_unlock_irqrestore(&gpio_lock, flags); | |
9c4ba946 | 1534 | might_sleep_if(chip->can_sleep); |
372e722e | 1535 | chip->free(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
1536 | spin_lock_irqsave(&gpio_lock, flags); |
1537 | } | |
d2876d08 | 1538 | desc_set_label(desc, NULL); |
438d8908 | 1539 | module_put(desc->chip->owner); |
07697461 | 1540 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); |
35e8bb51 | 1541 | clear_bit(FLAG_REQUESTED, &desc->flags); |
aca5ce14 | 1542 | clear_bit(FLAG_OPEN_DRAIN, &desc->flags); |
25553ff0 | 1543 | clear_bit(FLAG_OPEN_SOURCE, &desc->flags); |
438d8908 | 1544 | } else |
d2876d08 DB |
1545 | WARN_ON(extra_checks); |
1546 | ||
1547 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1548 | } | |
372e722e AC |
1549 | |
1550 | void gpio_free(unsigned gpio) | |
1551 | { | |
1552 | gpiod_free(gpio_to_desc(gpio)); | |
1553 | } | |
d2876d08 DB |
1554 | EXPORT_SYMBOL_GPL(gpio_free); |
1555 | ||
3e45f1d1 EM |
1556 | /** |
1557 | * gpio_request_one - request a single GPIO with initial configuration | |
1558 | * @gpio: the GPIO number | |
1559 | * @flags: GPIO configuration as specified by GPIOF_* | |
1560 | * @label: a literal description string of this GPIO | |
1561 | */ | |
1562 | int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) | |
1563 | { | |
372e722e | 1564 | struct gpio_desc *desc; |
3e45f1d1 EM |
1565 | int err; |
1566 | ||
372e722e AC |
1567 | desc = gpio_to_desc(gpio); |
1568 | ||
1569 | err = gpiod_request(desc, label); | |
3e45f1d1 EM |
1570 | if (err) |
1571 | return err; | |
1572 | ||
aca5ce14 | 1573 | if (flags & GPIOF_OPEN_DRAIN) |
372e722e | 1574 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); |
aca5ce14 | 1575 | |
25553ff0 | 1576 | if (flags & GPIOF_OPEN_SOURCE) |
372e722e | 1577 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); |
25553ff0 | 1578 | |
3e45f1d1 | 1579 | if (flags & GPIOF_DIR_IN) |
372e722e | 1580 | err = gpiod_direction_input(desc); |
3e45f1d1 | 1581 | else |
372e722e | 1582 | err = gpiod_direction_output(desc, |
3e45f1d1 EM |
1583 | (flags & GPIOF_INIT_HIGH) ? 1 : 0); |
1584 | ||
e254811c | 1585 | if (err) |
fc3a1f04 WS |
1586 | goto free_gpio; |
1587 | ||
1588 | if (flags & GPIOF_EXPORT) { | |
372e722e | 1589 | err = gpiod_export(desc, flags & GPIOF_EXPORT_CHANGEABLE); |
fc3a1f04 WS |
1590 | if (err) |
1591 | goto free_gpio; | |
1592 | } | |
1593 | ||
1594 | return 0; | |
e254811c | 1595 | |
fc3a1f04 | 1596 | free_gpio: |
372e722e | 1597 | gpiod_free(desc); |
3e45f1d1 EM |
1598 | return err; |
1599 | } | |
1600 | EXPORT_SYMBOL_GPL(gpio_request_one); | |
1601 | ||
1602 | /** | |
1603 | * gpio_request_array - request multiple GPIOs in a single call | |
1604 | * @array: array of the 'struct gpio' | |
1605 | * @num: how many GPIOs in the array | |
1606 | */ | |
7c295975 | 1607 | int gpio_request_array(const struct gpio *array, size_t num) |
3e45f1d1 EM |
1608 | { |
1609 | int i, err; | |
1610 | ||
1611 | for (i = 0; i < num; i++, array++) { | |
1612 | err = gpio_request_one(array->gpio, array->flags, array->label); | |
1613 | if (err) | |
1614 | goto err_free; | |
1615 | } | |
1616 | return 0; | |
1617 | ||
1618 | err_free: | |
1619 | while (i--) | |
1620 | gpio_free((--array)->gpio); | |
1621 | return err; | |
1622 | } | |
1623 | EXPORT_SYMBOL_GPL(gpio_request_array); | |
1624 | ||
1625 | /** | |
1626 | * gpio_free_array - release multiple GPIOs in a single call | |
1627 | * @array: array of the 'struct gpio' | |
1628 | * @num: how many GPIOs in the array | |
1629 | */ | |
7c295975 | 1630 | void gpio_free_array(const struct gpio *array, size_t num) |
3e45f1d1 EM |
1631 | { |
1632 | while (num--) | |
1633 | gpio_free((array++)->gpio); | |
1634 | } | |
1635 | EXPORT_SYMBOL_GPL(gpio_free_array); | |
d2876d08 DB |
1636 | |
1637 | /** | |
1638 | * gpiochip_is_requested - return string iff signal was requested | |
1639 | * @chip: controller managing the signal | |
1640 | * @offset: of signal within controller's 0..(ngpio - 1) range | |
1641 | * | |
1642 | * Returns NULL if the GPIO is not currently requested, else a string. | |
1643 | * If debugfs support is enabled, the string returned is the label passed | |
1644 | * to gpio_request(); otherwise it is a meaningless constant. | |
1645 | * | |
1646 | * This function is for use by GPIO controller drivers. The label can | |
1647 | * help with diagnostics, and knowing that the signal is used as a GPIO | |
1648 | * can help avoid accidentally multiplexing it to another controller. | |
1649 | */ | |
1650 | const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) | |
1651 | { | |
6c0b4e6c | 1652 | struct gpio_desc *desc; |
d2876d08 | 1653 | |
6c0b4e6c | 1654 | if (!GPIO_OFFSET_VALID(chip, offset)) |
d2876d08 | 1655 | return NULL; |
6c0b4e6c AC |
1656 | |
1657 | desc = &chip->desc[offset]; | |
1658 | ||
372e722e | 1659 | if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) |
d2876d08 DB |
1660 | return NULL; |
1661 | #ifdef CONFIG_DEBUG_FS | |
372e722e | 1662 | return desc->label; |
d2876d08 DB |
1663 | #else |
1664 | return "?"; | |
1665 | #endif | |
1666 | } | |
1667 | EXPORT_SYMBOL_GPL(gpiochip_is_requested); | |
1668 | ||
1669 | ||
1670 | /* Drivers MUST set GPIO direction before making get/set calls. In | |
1671 | * some cases this is done in early boot, before IRQs are enabled. | |
1672 | * | |
1673 | * As a rule these aren't called more than once (except for drivers | |
1674 | * using the open-drain emulation idiom) so these are natural places | |
1675 | * to accumulate extra debugging checks. Note that we can't (yet) | |
1676 | * rely on gpio_request() having been called beforehand. | |
1677 | */ | |
1678 | ||
79a9becd AC |
1679 | /** |
1680 | * gpiod_direction_input - set the GPIO direction to input | |
1681 | * @desc: GPIO to set to input | |
1682 | * | |
1683 | * Set the direction of the passed GPIO to input, such as gpiod_get_value() can | |
1684 | * be called safely on it. | |
1685 | * | |
1686 | * Return 0 in case of success, else an error code. | |
1687 | */ | |
1688 | int gpiod_direction_input(struct gpio_desc *desc) | |
d2876d08 DB |
1689 | { |
1690 | unsigned long flags; | |
1691 | struct gpio_chip *chip; | |
d2876d08 | 1692 | int status = -EINVAL; |
372e722e | 1693 | int offset; |
d2876d08 | 1694 | |
be1a4b13 | 1695 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1696 | pr_warn("%s: invalid GPIO\n", __func__); |
1697 | return -EINVAL; | |
1698 | } | |
1699 | ||
be1a4b13 LW |
1700 | chip = desc->chip; |
1701 | if (!chip->get || !chip->direction_input) { | |
6424de5a MB |
1702 | gpiod_warn(desc, |
1703 | "%s: missing get() or direction_input() operations\n", | |
1704 | __func__); | |
be1a4b13 LW |
1705 | return -EIO; |
1706 | } | |
1707 | ||
d2876d08 DB |
1708 | spin_lock_irqsave(&gpio_lock, flags); |
1709 | ||
372e722e | 1710 | status = gpio_ensure_requested(desc); |
35e8bb51 DB |
1711 | if (status < 0) |
1712 | goto fail; | |
d2876d08 DB |
1713 | |
1714 | /* now we know the gpio is valid and chip won't vanish */ | |
1715 | ||
1716 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1717 | ||
9c4ba946 | 1718 | might_sleep_if(chip->can_sleep); |
d2876d08 | 1719 | |
372e722e | 1720 | offset = gpio_chip_hwgpio(desc); |
35e8bb51 | 1721 | if (status) { |
372e722e | 1722 | status = chip->request(chip, offset); |
35e8bb51 | 1723 | if (status < 0) { |
6424de5a | 1724 | gpiod_dbg(desc, "chip request fail, %d\n", status); |
35e8bb51 DB |
1725 | /* and it's not available to anyone else ... |
1726 | * gpio_request() is the fully clean solution. | |
1727 | */ | |
1728 | goto lose; | |
1729 | } | |
1730 | } | |
1731 | ||
372e722e | 1732 | status = chip->direction_input(chip, offset); |
d2876d08 DB |
1733 | if (status == 0) |
1734 | clear_bit(FLAG_IS_OUT, &desc->flags); | |
3f397c21 | 1735 | |
372e722e | 1736 | trace_gpio_direction(desc_to_gpio(desc), 1, status); |
35e8bb51 | 1737 | lose: |
d2876d08 DB |
1738 | return status; |
1739 | fail: | |
1740 | spin_unlock_irqrestore(&gpio_lock, flags); | |
bcabdef1 | 1741 | if (status) |
6424de5a | 1742 | gpiod_dbg(desc, "%s status %d\n", __func__, status); |
d2876d08 DB |
1743 | return status; |
1744 | } | |
79a9becd | 1745 | EXPORT_SYMBOL_GPL(gpiod_direction_input); |
372e722e | 1746 | |
79a9becd AC |
1747 | /** |
1748 | * gpiod_direction_output - set the GPIO direction to input | |
1749 | * @desc: GPIO to set to output | |
1750 | * @value: initial output value of the GPIO | |
1751 | * | |
1752 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
1753 | * be called safely on it. The initial value of the output must be specified. | |
1754 | * | |
1755 | * Return 0 in case of success, else an error code. | |
1756 | */ | |
1757 | int gpiod_direction_output(struct gpio_desc *desc, int value) | |
d2876d08 DB |
1758 | { |
1759 | unsigned long flags; | |
1760 | struct gpio_chip *chip; | |
d2876d08 | 1761 | int status = -EINVAL; |
372e722e | 1762 | int offset; |
d2876d08 | 1763 | |
be1a4b13 | 1764 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1765 | pr_warn("%s: invalid GPIO\n", __func__); |
1766 | return -EINVAL; | |
1767 | } | |
1768 | ||
d468bf9e LW |
1769 | /* GPIOs used for IRQs shall not be set as output */ |
1770 | if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) { | |
1771 | gpiod_err(desc, | |
1772 | "%s: tried to set a GPIO tied to an IRQ as output\n", | |
1773 | __func__); | |
1774 | return -EIO; | |
1775 | } | |
1776 | ||
aca5ce14 LD |
1777 | /* Open drain pin should not be driven to 1 */ |
1778 | if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
372e722e | 1779 | return gpiod_direction_input(desc); |
aca5ce14 | 1780 | |
25553ff0 LD |
1781 | /* Open source pin should not be driven to 0 */ |
1782 | if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
372e722e | 1783 | return gpiod_direction_input(desc); |
25553ff0 | 1784 | |
be1a4b13 LW |
1785 | chip = desc->chip; |
1786 | if (!chip->set || !chip->direction_output) { | |
6424de5a MB |
1787 | gpiod_warn(desc, |
1788 | "%s: missing set() or direction_output() operations\n", | |
1789 | __func__); | |
be1a4b13 LW |
1790 | return -EIO; |
1791 | } | |
1792 | ||
d2876d08 DB |
1793 | spin_lock_irqsave(&gpio_lock, flags); |
1794 | ||
372e722e | 1795 | status = gpio_ensure_requested(desc); |
35e8bb51 DB |
1796 | if (status < 0) |
1797 | goto fail; | |
d2876d08 DB |
1798 | |
1799 | /* now we know the gpio is valid and chip won't vanish */ | |
1800 | ||
1801 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1802 | ||
9c4ba946 | 1803 | might_sleep_if(chip->can_sleep); |
d2876d08 | 1804 | |
372e722e | 1805 | offset = gpio_chip_hwgpio(desc); |
35e8bb51 | 1806 | if (status) { |
372e722e | 1807 | status = chip->request(chip, offset); |
35e8bb51 | 1808 | if (status < 0) { |
6424de5a | 1809 | gpiod_dbg(desc, "chip request fail, %d\n", status); |
35e8bb51 DB |
1810 | /* and it's not available to anyone else ... |
1811 | * gpio_request() is the fully clean solution. | |
1812 | */ | |
1813 | goto lose; | |
1814 | } | |
1815 | } | |
1816 | ||
372e722e | 1817 | status = chip->direction_output(chip, offset, value); |
d2876d08 DB |
1818 | if (status == 0) |
1819 | set_bit(FLAG_IS_OUT, &desc->flags); | |
372e722e AC |
1820 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
1821 | trace_gpio_direction(desc_to_gpio(desc), 0, status); | |
35e8bb51 | 1822 | lose: |
d2876d08 DB |
1823 | return status; |
1824 | fail: | |
1825 | spin_unlock_irqrestore(&gpio_lock, flags); | |
bcabdef1 | 1826 | if (status) |
6424de5a | 1827 | gpiod_dbg(desc, "%s: gpio status %d\n", __func__, status); |
d2876d08 DB |
1828 | return status; |
1829 | } | |
79a9becd | 1830 | EXPORT_SYMBOL_GPL(gpiod_direction_output); |
d2876d08 | 1831 | |
c4b5be98 | 1832 | /** |
79a9becd | 1833 | * gpiod_set_debounce - sets @debounce time for a @gpio |
c4b5be98 FB |
1834 | * @gpio: the gpio to set debounce time |
1835 | * @debounce: debounce time is microseconds | |
65d87656 LW |
1836 | * |
1837 | * returns -ENOTSUPP if the controller does not support setting | |
1838 | * debounce. | |
c4b5be98 | 1839 | */ |
79a9becd | 1840 | int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) |
c4b5be98 FB |
1841 | { |
1842 | unsigned long flags; | |
1843 | struct gpio_chip *chip; | |
c4b5be98 | 1844 | int status = -EINVAL; |
372e722e | 1845 | int offset; |
c4b5be98 | 1846 | |
be1a4b13 | 1847 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1848 | pr_warn("%s: invalid GPIO\n", __func__); |
1849 | return -EINVAL; | |
1850 | } | |
1851 | ||
c4b5be98 | 1852 | chip = desc->chip; |
be1a4b13 | 1853 | if (!chip->set || !chip->set_debounce) { |
6424de5a MB |
1854 | gpiod_dbg(desc, |
1855 | "%s: missing set() or set_debounce() operations\n", | |
1856 | __func__); | |
65d87656 | 1857 | return -ENOTSUPP; |
be1a4b13 LW |
1858 | } |
1859 | ||
1860 | spin_lock_irqsave(&gpio_lock, flags); | |
372e722e AC |
1861 | |
1862 | status = gpio_ensure_requested(desc); | |
c4b5be98 FB |
1863 | if (status < 0) |
1864 | goto fail; | |
1865 | ||
1866 | /* now we know the gpio is valid and chip won't vanish */ | |
1867 | ||
1868 | spin_unlock_irqrestore(&gpio_lock, flags); | |
1869 | ||
9c4ba946 | 1870 | might_sleep_if(chip->can_sleep); |
c4b5be98 | 1871 | |
372e722e AC |
1872 | offset = gpio_chip_hwgpio(desc); |
1873 | return chip->set_debounce(chip, offset, debounce); | |
c4b5be98 FB |
1874 | |
1875 | fail: | |
1876 | spin_unlock_irqrestore(&gpio_lock, flags); | |
bcabdef1 | 1877 | if (status) |
6424de5a | 1878 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
c4b5be98 FB |
1879 | |
1880 | return status; | |
1881 | } | |
79a9becd | 1882 | EXPORT_SYMBOL_GPL(gpiod_set_debounce); |
372e722e | 1883 | |
79a9becd AC |
1884 | /** |
1885 | * gpiod_is_active_low - test whether a GPIO is active-low or not | |
1886 | * @desc: the gpio descriptor to test | |
1887 | * | |
1888 | * Returns 1 if the GPIO is active-low, 0 otherwise. | |
1889 | */ | |
1890 | int gpiod_is_active_low(const struct gpio_desc *desc) | |
372e722e | 1891 | { |
79a9becd | 1892 | return test_bit(FLAG_ACTIVE_LOW, &desc->flags); |
372e722e | 1893 | } |
79a9becd | 1894 | EXPORT_SYMBOL_GPL(gpiod_is_active_low); |
d2876d08 DB |
1895 | |
1896 | /* I/O calls are only valid after configuration completed; the relevant | |
1897 | * "is this a valid GPIO" error checks should already have been done. | |
1898 | * | |
1899 | * "Get" operations are often inlinable as reading a pin value register, | |
1900 | * and masking the relevant bit in that register. | |
1901 | * | |
1902 | * When "set" operations are inlinable, they involve writing that mask to | |
1903 | * one register to set a low value, or a different register to set it high. | |
1904 | * Otherwise locking is needed, so there may be little value to inlining. | |
1905 | * | |
1906 | *------------------------------------------------------------------------ | |
1907 | * | |
1908 | * IMPORTANT!!! The hot paths -- get/set value -- assume that callers | |
1909 | * have requested the GPIO. That can include implicit requesting by | |
1910 | * a direction setting call. Marking a gpio as requested locks its chip | |
1911 | * in memory, guaranteeing that these table lookups need no more locking | |
1912 | * and that gpiochip_remove() will fail. | |
1913 | * | |
1914 | * REVISIT when debugging, consider adding some instrumentation to ensure | |
1915 | * that the GPIO was actually requested. | |
1916 | */ | |
1917 | ||
79a9becd | 1918 | static int _gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 DB |
1919 | { |
1920 | struct gpio_chip *chip; | |
3f397c21 | 1921 | int value; |
372e722e | 1922 | int offset; |
d2876d08 | 1923 | |
372e722e AC |
1924 | chip = desc->chip; |
1925 | offset = gpio_chip_hwgpio(desc); | |
372e722e AC |
1926 | value = chip->get ? chip->get(chip, offset) : 0; |
1927 | trace_gpio_value(desc_to_gpio(desc), 1, value); | |
3f397c21 | 1928 | return value; |
d2876d08 | 1929 | } |
372e722e | 1930 | |
d2876d08 | 1931 | /** |
79a9becd AC |
1932 | * gpiod_get_raw_value() - return a gpio's raw value |
1933 | * @desc: gpio whose value will be returned | |
d2876d08 | 1934 | * |
79a9becd AC |
1935 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding |
1936 | * its ACTIVE_LOW status. | |
1937 | * | |
1938 | * This function should be called from contexts where we cannot sleep, and will | |
1939 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1940 | */ |
79a9becd | 1941 | int gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 | 1942 | { |
bcabdef1 AC |
1943 | if (!desc) |
1944 | return 0; | |
e4e449e8 | 1945 | /* Should be using gpio_get_value_cansleep() */ |
d8e0ac08 | 1946 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 1947 | return _gpiod_get_raw_value(desc); |
d2876d08 | 1948 | } |
79a9becd | 1949 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value); |
372e722e | 1950 | |
79a9becd AC |
1951 | /** |
1952 | * gpiod_get_value() - return a gpio's value | |
1953 | * @desc: gpio whose value will be returned | |
1954 | * | |
1955 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
1956 | * account. | |
1957 | * | |
1958 | * This function should be called from contexts where we cannot sleep, and will | |
1959 | * complain if the GPIO chip functions potentially sleep. | |
1960 | */ | |
1961 | int gpiod_get_value(const struct gpio_desc *desc) | |
372e722e | 1962 | { |
79a9becd AC |
1963 | int value; |
1964 | if (!desc) | |
1965 | return 0; | |
1966 | /* Should be using gpio_get_value_cansleep() */ | |
1967 | WARN_ON(desc->chip->can_sleep); | |
1968 | ||
1969 | value = _gpiod_get_raw_value(desc); | |
1970 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1971 | value = !value; | |
1972 | ||
1973 | return value; | |
372e722e | 1974 | } |
79a9becd | 1975 | EXPORT_SYMBOL_GPL(gpiod_get_value); |
d2876d08 | 1976 | |
aca5ce14 LD |
1977 | /* |
1978 | * _gpio_set_open_drain_value() - Set the open drain gpio's value. | |
79a9becd | 1979 | * @desc: gpio descriptor whose state need to be set. |
aca5ce14 LD |
1980 | * @value: Non-zero for setting it HIGH otherise it will set to LOW. |
1981 | */ | |
372e722e | 1982 | static void _gpio_set_open_drain_value(struct gpio_desc *desc, int value) |
aca5ce14 LD |
1983 | { |
1984 | int err = 0; | |
372e722e AC |
1985 | struct gpio_chip *chip = desc->chip; |
1986 | int offset = gpio_chip_hwgpio(desc); | |
1987 | ||
aca5ce14 | 1988 | if (value) { |
372e722e | 1989 | err = chip->direction_input(chip, offset); |
aca5ce14 | 1990 | if (!err) |
372e722e | 1991 | clear_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 1992 | } else { |
372e722e | 1993 | err = chip->direction_output(chip, offset, 0); |
aca5ce14 | 1994 | if (!err) |
372e722e | 1995 | set_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 1996 | } |
372e722e | 1997 | trace_gpio_direction(desc_to_gpio(desc), value, err); |
aca5ce14 | 1998 | if (err < 0) |
6424de5a MB |
1999 | gpiod_err(desc, |
2000 | "%s: Error in set_value for open drain err %d\n", | |
2001 | __func__, err); | |
aca5ce14 LD |
2002 | } |
2003 | ||
25553ff0 | 2004 | /* |
79a9becd AC |
2005 | * _gpio_set_open_source_value() - Set the open source gpio's value. |
2006 | * @desc: gpio descriptor whose state need to be set. | |
25553ff0 LD |
2007 | * @value: Non-zero for setting it HIGH otherise it will set to LOW. |
2008 | */ | |
372e722e | 2009 | static void _gpio_set_open_source_value(struct gpio_desc *desc, int value) |
25553ff0 LD |
2010 | { |
2011 | int err = 0; | |
372e722e AC |
2012 | struct gpio_chip *chip = desc->chip; |
2013 | int offset = gpio_chip_hwgpio(desc); | |
2014 | ||
25553ff0 | 2015 | if (value) { |
372e722e | 2016 | err = chip->direction_output(chip, offset, 1); |
25553ff0 | 2017 | if (!err) |
372e722e | 2018 | set_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 2019 | } else { |
372e722e | 2020 | err = chip->direction_input(chip, offset); |
25553ff0 | 2021 | if (!err) |
372e722e | 2022 | clear_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 2023 | } |
372e722e | 2024 | trace_gpio_direction(desc_to_gpio(desc), !value, err); |
25553ff0 | 2025 | if (err < 0) |
6424de5a MB |
2026 | gpiod_err(desc, |
2027 | "%s: Error in set_value for open source err %d\n", | |
2028 | __func__, err); | |
25553ff0 LD |
2029 | } |
2030 | ||
79a9becd | 2031 | static void _gpiod_set_raw_value(struct gpio_desc *desc, int value) |
d2876d08 DB |
2032 | { |
2033 | struct gpio_chip *chip; | |
2034 | ||
372e722e | 2035 | chip = desc->chip; |
372e722e AC |
2036 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
2037 | if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
2038 | _gpio_set_open_drain_value(desc, value); | |
2039 | else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
2040 | _gpio_set_open_source_value(desc, value); | |
aca5ce14 | 2041 | else |
372e722e AC |
2042 | chip->set(chip, gpio_chip_hwgpio(desc), value); |
2043 | } | |
2044 | ||
d2876d08 | 2045 | /** |
79a9becd AC |
2046 | * gpiod_set_raw_value() - assign a gpio's raw value |
2047 | * @desc: gpio whose value will be assigned | |
d2876d08 | 2048 | * @value: value to assign |
d2876d08 | 2049 | * |
79a9becd AC |
2050 | * Set the raw value of the GPIO, i.e. the value of its physical line without |
2051 | * regard for its ACTIVE_LOW status. | |
2052 | * | |
2053 | * This function should be called from contexts where we cannot sleep, and will | |
2054 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 2055 | */ |
79a9becd | 2056 | void gpiod_set_raw_value(struct gpio_desc *desc, int value) |
372e722e | 2057 | { |
bcabdef1 AC |
2058 | if (!desc) |
2059 | return; | |
e4e449e8 | 2060 | /* Should be using gpio_set_value_cansleep() */ |
d8e0ac08 | 2061 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 2062 | _gpiod_set_raw_value(desc, value); |
d2876d08 | 2063 | } |
79a9becd | 2064 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value); |
d2876d08 DB |
2065 | |
2066 | /** | |
79a9becd AC |
2067 | * gpiod_set_value() - assign a gpio's value |
2068 | * @desc: gpio whose value will be assigned | |
2069 | * @value: value to assign | |
2070 | * | |
2071 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
2072 | * account | |
d2876d08 | 2073 | * |
79a9becd AC |
2074 | * This function should be called from contexts where we cannot sleep, and will |
2075 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 2076 | */ |
79a9becd | 2077 | void gpiod_set_value(struct gpio_desc *desc, int value) |
d2876d08 | 2078 | { |
bcabdef1 | 2079 | if (!desc) |
79a9becd AC |
2080 | return; |
2081 | /* Should be using gpio_set_value_cansleep() */ | |
2082 | WARN_ON(desc->chip->can_sleep); | |
2083 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2084 | value = !value; | |
2085 | _gpiod_set_raw_value(desc, value); | |
372e722e | 2086 | } |
79a9becd | 2087 | EXPORT_SYMBOL_GPL(gpiod_set_value); |
d2876d08 | 2088 | |
d2876d08 | 2089 | /** |
79a9becd AC |
2090 | * gpiod_cansleep() - report whether gpio value access may sleep |
2091 | * @desc: gpio to check | |
d2876d08 | 2092 | * |
d2876d08 | 2093 | */ |
79a9becd | 2094 | int gpiod_cansleep(const struct gpio_desc *desc) |
372e722e | 2095 | { |
bcabdef1 AC |
2096 | if (!desc) |
2097 | return 0; | |
372e722e | 2098 | return desc->chip->can_sleep; |
d2876d08 | 2099 | } |
79a9becd | 2100 | EXPORT_SYMBOL_GPL(gpiod_cansleep); |
d2876d08 | 2101 | |
0f6d504e | 2102 | /** |
79a9becd AC |
2103 | * gpiod_to_irq() - return the IRQ corresponding to a GPIO |
2104 | * @desc: gpio whose IRQ will be returned (already requested) | |
0f6d504e | 2105 | * |
79a9becd AC |
2106 | * Return the IRQ corresponding to the passed GPIO, or an error code in case of |
2107 | * error. | |
0f6d504e | 2108 | */ |
79a9becd | 2109 | int gpiod_to_irq(const struct gpio_desc *desc) |
0f6d504e DB |
2110 | { |
2111 | struct gpio_chip *chip; | |
372e722e | 2112 | int offset; |
0f6d504e | 2113 | |
bcabdef1 AC |
2114 | if (!desc) |
2115 | return -EINVAL; | |
372e722e AC |
2116 | chip = desc->chip; |
2117 | offset = gpio_chip_hwgpio(desc); | |
2118 | return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO; | |
0f6d504e | 2119 | } |
79a9becd | 2120 | EXPORT_SYMBOL_GPL(gpiod_to_irq); |
0f6d504e | 2121 | |
d468bf9e LW |
2122 | /** |
2123 | * gpiod_lock_as_irq() - lock a GPIO to be used as IRQ | |
2124 | * @gpio: the GPIO line to lock as used for IRQ | |
2125 | * | |
2126 | * This is used directly by GPIO drivers that want to lock down | |
2127 | * a certain GPIO line to be used as IRQs, for example in the | |
2128 | * .to_irq() callback of their gpio_chip, or in the .irq_enable() | |
2129 | * of its irq_chip implementation if the GPIO is known from that | |
2130 | * code. | |
2131 | */ | |
79a9becd | 2132 | int gpiod_lock_as_irq(struct gpio_desc *desc) |
372e722e | 2133 | { |
d468bf9e LW |
2134 | if (!desc) |
2135 | return -EINVAL; | |
2136 | ||
2137 | if (test_bit(FLAG_IS_OUT, &desc->flags)) { | |
2138 | gpiod_err(desc, | |
2139 | "%s: tried to flag a GPIO set as output for IRQ\n", | |
2140 | __func__); | |
2141 | return -EIO; | |
2142 | } | |
2143 | ||
2144 | set_bit(FLAG_USED_AS_IRQ, &desc->flags); | |
2145 | return 0; | |
372e722e | 2146 | } |
79a9becd | 2147 | EXPORT_SYMBOL_GPL(gpiod_lock_as_irq); |
d2876d08 | 2148 | |
d468bf9e LW |
2149 | int gpio_lock_as_irq(struct gpio_chip *chip, unsigned int offset) |
2150 | { | |
2151 | return gpiod_lock_as_irq(gpiochip_offset_to_desc(chip, offset)); | |
2152 | } | |
2153 | EXPORT_SYMBOL_GPL(gpio_lock_as_irq); | |
d2876d08 | 2154 | |
d468bf9e LW |
2155 | /** |
2156 | * gpiod_unlock_as_irq() - unlock a GPIO used as IRQ | |
2157 | * @gpio: the GPIO line to unlock from IRQ usage | |
2158 | * | |
2159 | * This is used directly by GPIO drivers that want to indicate | |
2160 | * that a certain GPIO is no longer used exclusively for IRQ. | |
d2876d08 | 2161 | */ |
79a9becd | 2162 | void gpiod_unlock_as_irq(struct gpio_desc *desc) |
d468bf9e LW |
2163 | { |
2164 | if (!desc) | |
2165 | return; | |
d2876d08 | 2166 | |
d468bf9e LW |
2167 | clear_bit(FLAG_USED_AS_IRQ, &desc->flags); |
2168 | } | |
79a9becd | 2169 | EXPORT_SYMBOL_GPL(gpiod_unlock_as_irq); |
d468bf9e LW |
2170 | |
2171 | void gpio_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) | |
2172 | { | |
2173 | return gpiod_unlock_as_irq(gpiochip_offset_to_desc(chip, offset)); | |
2174 | } | |
2175 | EXPORT_SYMBOL_GPL(gpio_unlock_as_irq); | |
d2876d08 | 2176 | |
79a9becd AC |
2177 | /** |
2178 | * gpiod_get_raw_value_cansleep() - return a gpio's raw value | |
2179 | * @desc: gpio whose value will be returned | |
2180 | * | |
2181 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding | |
2182 | * its ACTIVE_LOW status. | |
2183 | * | |
2184 | * This function is to be called from contexts that can sleep. | |
d2876d08 | 2185 | */ |
79a9becd | 2186 | int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) |
d2876d08 | 2187 | { |
d2876d08 | 2188 | might_sleep_if(extra_checks); |
bcabdef1 AC |
2189 | if (!desc) |
2190 | return 0; | |
79a9becd | 2191 | return _gpiod_get_raw_value(desc); |
d2876d08 | 2192 | } |
79a9becd | 2193 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); |
372e722e | 2194 | |
79a9becd AC |
2195 | /** |
2196 | * gpiod_get_value_cansleep() - return a gpio's value | |
2197 | * @desc: gpio whose value will be returned | |
2198 | * | |
2199 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
2200 | * account. | |
2201 | * | |
2202 | * This function is to be called from contexts that can sleep. | |
2203 | */ | |
2204 | int gpiod_get_value_cansleep(const struct gpio_desc *desc) | |
d2876d08 | 2205 | { |
3f397c21 | 2206 | int value; |
d2876d08 DB |
2207 | |
2208 | might_sleep_if(extra_checks); | |
bcabdef1 AC |
2209 | if (!desc) |
2210 | return 0; | |
79a9becd AC |
2211 | |
2212 | value = _gpiod_get_raw_value(desc); | |
2213 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2214 | value = !value; | |
2215 | ||
3f397c21 | 2216 | return value; |
d2876d08 | 2217 | } |
79a9becd | 2218 | EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); |
372e722e | 2219 | |
79a9becd AC |
2220 | /** |
2221 | * gpiod_set_raw_value_cansleep() - assign a gpio's raw value | |
2222 | * @desc: gpio whose value will be assigned | |
2223 | * @value: value to assign | |
2224 | * | |
2225 | * Set the raw value of the GPIO, i.e. the value of its physical line without | |
2226 | * regard for its ACTIVE_LOW status. | |
2227 | * | |
2228 | * This function is to be called from contexts that can sleep. | |
2229 | */ | |
2230 | void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) | |
372e722e | 2231 | { |
d2876d08 | 2232 | might_sleep_if(extra_checks); |
bcabdef1 AC |
2233 | if (!desc) |
2234 | return; | |
79a9becd | 2235 | _gpiod_set_raw_value(desc, value); |
372e722e | 2236 | } |
79a9becd | 2237 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); |
d2876d08 | 2238 | |
79a9becd AC |
2239 | /** |
2240 | * gpiod_set_value_cansleep() - assign a gpio's value | |
2241 | * @desc: gpio whose value will be assigned | |
2242 | * @value: value to assign | |
2243 | * | |
2244 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
2245 | * account | |
2246 | * | |
2247 | * This function is to be called from contexts that can sleep. | |
2248 | */ | |
2249 | void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) | |
d2876d08 | 2250 | { |
d2876d08 | 2251 | might_sleep_if(extra_checks); |
bcabdef1 AC |
2252 | if (!desc) |
2253 | return; | |
79a9becd AC |
2254 | |
2255 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
2256 | value = !value; | |
2257 | _gpiod_set_raw_value(desc, value); | |
372e722e | 2258 | } |
79a9becd | 2259 | EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); |
d2876d08 | 2260 | |
bae48da2 AC |
2261 | /** |
2262 | * gpiod_add_table() - register GPIO device consumers | |
2263 | * @table: array of consumers to register | |
2264 | * @num: number of consumers in table | |
2265 | */ | |
2266 | void gpiod_add_table(struct gpiod_lookup *table, size_t size) | |
2267 | { | |
2268 | mutex_lock(&gpio_lookup_lock); | |
2269 | ||
2270 | while (size--) { | |
2271 | list_add_tail(&table->list, &gpio_lookup_list); | |
2272 | table++; | |
2273 | } | |
2274 | ||
2275 | mutex_unlock(&gpio_lookup_lock); | |
2276 | } | |
2277 | ||
bae48da2 AC |
2278 | #ifdef CONFIG_OF |
2279 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, | |
53e7cac3 AC |
2280 | unsigned int idx, |
2281 | enum gpio_lookup_flags *flags) | |
bae48da2 AC |
2282 | { |
2283 | char prop_name[32]; /* 32 is max size of property name */ | |
2284 | enum of_gpio_flags of_flags; | |
2285 | struct gpio_desc *desc; | |
2286 | ||
2287 | if (con_id) | |
2288 | snprintf(prop_name, 32, "%s-gpios", con_id); | |
aca5ce14 | 2289 | else |
bae48da2 AC |
2290 | snprintf(prop_name, 32, "gpios"); |
2291 | ||
2292 | desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx, | |
2293 | &of_flags); | |
2294 | ||
2295 | if (IS_ERR(desc)) | |
2296 | return desc; | |
2297 | ||
2298 | if (of_flags & OF_GPIO_ACTIVE_LOW) | |
53e7cac3 | 2299 | *flags |= GPIO_ACTIVE_LOW; |
bae48da2 AC |
2300 | |
2301 | return desc; | |
2302 | } | |
2303 | #else | |
2304 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, | |
209e64f9 AC |
2305 | unsigned int idx, |
2306 | enum gpio_lookup_flags *flags) | |
bae48da2 AC |
2307 | { |
2308 | return ERR_PTR(-ENODEV); | |
d2876d08 | 2309 | } |
bae48da2 | 2310 | #endif |
d2876d08 | 2311 | |
81f59e9d | 2312 | static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id, |
53e7cac3 AC |
2313 | unsigned int idx, |
2314 | enum gpio_lookup_flags *flags) | |
372e722e | 2315 | { |
e01f440a MW |
2316 | struct acpi_gpio_info info; |
2317 | struct gpio_desc *desc; | |
2318 | ||
2319 | desc = acpi_get_gpiod_by_index(dev, idx, &info); | |
2320 | if (IS_ERR(desc)) | |
2321 | return desc; | |
2322 | ||
2323 | if (info.gpioint && info.active_low) | |
53e7cac3 | 2324 | *flags |= GPIO_ACTIVE_LOW; |
e01f440a MW |
2325 | |
2326 | return desc; | |
81f59e9d MW |
2327 | } |
2328 | ||
bae48da2 | 2329 | static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, |
53e7cac3 AC |
2330 | unsigned int idx, |
2331 | enum gpio_lookup_flags *flags) | |
bae48da2 AC |
2332 | { |
2333 | const char *dev_id = dev ? dev_name(dev) : NULL; | |
2334 | struct gpio_desc *desc = ERR_PTR(-ENODEV); | |
2335 | unsigned int match, best = 0; | |
2336 | struct gpiod_lookup *p; | |
2337 | ||
2338 | mutex_lock(&gpio_lookup_lock); | |
2339 | ||
2340 | list_for_each_entry(p, &gpio_lookup_list, list) { | |
2341 | match = 0; | |
2342 | ||
2343 | if (p->dev_id) { | |
2344 | if (!dev_id || strcmp(p->dev_id, dev_id)) | |
2345 | continue; | |
2346 | ||
2347 | match += 2; | |
2348 | } | |
2349 | ||
2350 | if (p->con_id) { | |
2351 | if (!con_id || strcmp(p->con_id, con_id)) | |
2352 | continue; | |
2353 | ||
2354 | match += 1; | |
2355 | } | |
2356 | ||
2357 | if (p->idx != idx) | |
2358 | continue; | |
2359 | ||
2360 | if (match > best) { | |
2361 | struct gpio_chip *chip; | |
2362 | ||
2363 | chip = find_chip_by_name(p->chip_label); | |
2364 | ||
2365 | if (!chip) { | |
2366 | dev_warn(dev, "cannot find GPIO chip %s\n", | |
2367 | p->chip_label); | |
2368 | continue; | |
2369 | } | |
2370 | ||
7cc67b9c | 2371 | if (chip->ngpio <= p->chip_hwnum) { |
bae48da2 AC |
2372 | dev_warn(dev, "GPIO chip %s has %d GPIOs\n", |
2373 | chip->label, chip->ngpio); | |
2374 | continue; | |
2375 | } | |
2376 | ||
2377 | desc = gpio_to_desc(chip->base + p->chip_hwnum); | |
2378 | *flags = p->flags; | |
2379 | ||
2380 | if (match != 3) | |
2381 | best = match; | |
2382 | else | |
2383 | break; | |
2384 | } | |
2385 | } | |
2386 | ||
2387 | mutex_unlock(&gpio_lookup_lock); | |
2388 | ||
2389 | return desc; | |
2390 | } | |
2391 | ||
2392 | /** | |
2393 | * gpio_get - obtain a GPIO for a given GPIO function | |
2394 | * @dev: GPIO consumer | |
2395 | * @con_id: function within the GPIO consumer | |
2396 | * | |
2397 | * Return the GPIO descriptor corresponding to the function con_id of device | |
2398 | * dev, or an IS_ERR() condition if an error occured. | |
2399 | */ | |
2400 | struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id) | |
2401 | { | |
2402 | return gpiod_get_index(dev, con_id, 0); | |
2403 | } | |
2404 | EXPORT_SYMBOL_GPL(gpiod_get); | |
2405 | ||
2406 | /** | |
2407 | * gpiod_get_index - obtain a GPIO from a multi-index GPIO function | |
2408 | * @dev: GPIO consumer | |
2409 | * @con_id: function within the GPIO consumer | |
2410 | * @idx: index of the GPIO to obtain in the consumer | |
2411 | * | |
2412 | * This variant of gpiod_get() allows to access GPIOs other than the first | |
2413 | * defined one for functions that define several GPIOs. | |
2414 | * | |
2415 | * Return a valid GPIO descriptor, or an IS_ERR() condition in case of error. | |
2416 | */ | |
2417 | struct gpio_desc *__must_check gpiod_get_index(struct device *dev, | |
2418 | const char *con_id, | |
2419 | unsigned int idx) | |
2420 | { | |
35c5d7fd | 2421 | struct gpio_desc *desc = NULL; |
bae48da2 | 2422 | int status; |
53e7cac3 | 2423 | enum gpio_lookup_flags flags = 0; |
bae48da2 AC |
2424 | |
2425 | dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); | |
2426 | ||
2427 | /* Using device tree? */ | |
2428 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) { | |
2429 | dev_dbg(dev, "using device tree for GPIO lookup\n"); | |
2430 | desc = of_find_gpio(dev, con_id, idx, &flags); | |
81f59e9d MW |
2431 | } else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) { |
2432 | dev_dbg(dev, "using ACPI for GPIO lookup\n"); | |
2433 | desc = acpi_find_gpio(dev, con_id, idx, &flags); | |
35c5d7fd AC |
2434 | } |
2435 | ||
2436 | /* | |
2437 | * Either we are not using DT or ACPI, or their lookup did not return | |
2438 | * a result. In that case, use platform lookup as a fallback. | |
2439 | */ | |
2440 | if (!desc || IS_ERR(desc)) { | |
2441 | struct gpio_desc *pdesc; | |
bae48da2 | 2442 | dev_dbg(dev, "using lookup tables for GPIO lookup"); |
35c5d7fd AC |
2443 | pdesc = gpiod_find(dev, con_id, idx, &flags); |
2444 | /* If used as fallback, do not replace the previous error */ | |
2445 | if (!IS_ERR(pdesc) || !desc) | |
2446 | desc = pdesc; | |
bae48da2 AC |
2447 | } |
2448 | ||
2449 | if (IS_ERR(desc)) { | |
2450 | dev_warn(dev, "lookup for GPIO %s failed\n", con_id); | |
2451 | return desc; | |
2452 | } | |
2453 | ||
2454 | status = gpiod_request(desc, con_id); | |
2455 | ||
2456 | if (status < 0) | |
2457 | return ERR_PTR(status); | |
2458 | ||
53e7cac3 | 2459 | if (flags & GPIO_ACTIVE_LOW) |
bae48da2 | 2460 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); |
53e7cac3 AC |
2461 | if (flags & GPIO_OPEN_DRAIN) |
2462 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); | |
2463 | if (flags & GPIO_OPEN_SOURCE) | |
2464 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); | |
bae48da2 AC |
2465 | |
2466 | return desc; | |
2467 | } | |
2468 | EXPORT_SYMBOL_GPL(gpiod_get_index); | |
2469 | ||
2470 | /** | |
2471 | * gpiod_put - dispose of a GPIO descriptor | |
2472 | * @desc: GPIO descriptor to dispose of | |
2473 | * | |
2474 | * No descriptor can be used after gpiod_put() has been called on it. | |
2475 | */ | |
2476 | void gpiod_put(struct gpio_desc *desc) | |
2477 | { | |
2478 | gpiod_free(desc); | |
372e722e | 2479 | } |
bae48da2 | 2480 | EXPORT_SYMBOL_GPL(gpiod_put); |
d2876d08 DB |
2481 | |
2482 | #ifdef CONFIG_DEBUG_FS | |
2483 | ||
d2876d08 DB |
2484 | static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip) |
2485 | { | |
2486 | unsigned i; | |
2487 | unsigned gpio = chip->base; | |
6c0b4e6c | 2488 | struct gpio_desc *gdesc = &chip->desc[0]; |
d2876d08 | 2489 | int is_out; |
d468bf9e | 2490 | int is_irq; |
d2876d08 DB |
2491 | |
2492 | for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) { | |
2493 | if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) | |
2494 | continue; | |
2495 | ||
372e722e | 2496 | gpiod_get_direction(gdesc); |
d2876d08 | 2497 | is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); |
d468bf9e LW |
2498 | is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); |
2499 | seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s", | |
d2876d08 DB |
2500 | gpio, gdesc->label, |
2501 | is_out ? "out" : "in ", | |
2502 | chip->get | |
2503 | ? (chip->get(chip, i) ? "hi" : "lo") | |
d468bf9e LW |
2504 | : "? ", |
2505 | is_irq ? "IRQ" : " "); | |
d2876d08 DB |
2506 | seq_printf(s, "\n"); |
2507 | } | |
2508 | } | |
2509 | ||
f9c4a31f | 2510 | static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) |
d2876d08 | 2511 | { |
362432ae | 2512 | unsigned long flags; |
f9c4a31f | 2513 | struct gpio_chip *chip = NULL; |
cb1650d4 | 2514 | loff_t index = *pos; |
d2876d08 | 2515 | |
f9c4a31f | 2516 | s->private = ""; |
d2876d08 | 2517 | |
362432ae | 2518 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 | 2519 | list_for_each_entry(chip, &gpio_chips, list) |
362432ae GL |
2520 | if (index-- == 0) { |
2521 | spin_unlock_irqrestore(&gpio_lock, flags); | |
cb1650d4 | 2522 | return chip; |
f9c4a31f | 2523 | } |
362432ae | 2524 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f | 2525 | |
cb1650d4 | 2526 | return NULL; |
f9c4a31f TR |
2527 | } |
2528 | ||
2529 | static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
2530 | { | |
362432ae | 2531 | unsigned long flags; |
f9c4a31f | 2532 | struct gpio_chip *chip = v; |
f9c4a31f TR |
2533 | void *ret = NULL; |
2534 | ||
362432ae | 2535 | spin_lock_irqsave(&gpio_lock, flags); |
cb1650d4 AC |
2536 | if (list_is_last(&chip->list, &gpio_chips)) |
2537 | ret = NULL; | |
2538 | else | |
2539 | ret = list_entry(chip->list.next, struct gpio_chip, list); | |
362432ae | 2540 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f TR |
2541 | |
2542 | s->private = "\n"; | |
2543 | ++*pos; | |
2544 | ||
2545 | return ret; | |
2546 | } | |
2547 | ||
2548 | static void gpiolib_seq_stop(struct seq_file *s, void *v) | |
2549 | { | |
2550 | } | |
2551 | ||
2552 | static int gpiolib_seq_show(struct seq_file *s, void *v) | |
2553 | { | |
2554 | struct gpio_chip *chip = v; | |
2555 | struct device *dev; | |
2556 | ||
2557 | seq_printf(s, "%sGPIOs %d-%d", (char *)s->private, | |
2558 | chip->base, chip->base + chip->ngpio - 1); | |
2559 | dev = chip->dev; | |
2560 | if (dev) | |
2561 | seq_printf(s, ", %s/%s", dev->bus ? dev->bus->name : "no-bus", | |
2562 | dev_name(dev)); | |
2563 | if (chip->label) | |
2564 | seq_printf(s, ", %s", chip->label); | |
2565 | if (chip->can_sleep) | |
2566 | seq_printf(s, ", can sleep"); | |
2567 | seq_printf(s, ":\n"); | |
2568 | ||
2569 | if (chip->dbg_show) | |
2570 | chip->dbg_show(s, chip); | |
2571 | else | |
2572 | gpiolib_dbg_show(s, chip); | |
2573 | ||
d2876d08 DB |
2574 | return 0; |
2575 | } | |
2576 | ||
f9c4a31f TR |
2577 | static const struct seq_operations gpiolib_seq_ops = { |
2578 | .start = gpiolib_seq_start, | |
2579 | .next = gpiolib_seq_next, | |
2580 | .stop = gpiolib_seq_stop, | |
2581 | .show = gpiolib_seq_show, | |
2582 | }; | |
2583 | ||
d2876d08 DB |
2584 | static int gpiolib_open(struct inode *inode, struct file *file) |
2585 | { | |
f9c4a31f | 2586 | return seq_open(file, &gpiolib_seq_ops); |
d2876d08 DB |
2587 | } |
2588 | ||
828c0950 | 2589 | static const struct file_operations gpiolib_operations = { |
f9c4a31f | 2590 | .owner = THIS_MODULE, |
d2876d08 DB |
2591 | .open = gpiolib_open, |
2592 | .read = seq_read, | |
2593 | .llseek = seq_lseek, | |
f9c4a31f | 2594 | .release = seq_release, |
d2876d08 DB |
2595 | }; |
2596 | ||
2597 | static int __init gpiolib_debugfs_init(void) | |
2598 | { | |
2599 | /* /sys/kernel/debug/gpio */ | |
2600 | (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO, | |
2601 | NULL, NULL, &gpiolib_operations); | |
2602 | return 0; | |
2603 | } | |
2604 | subsys_initcall(gpiolib_debugfs_init); | |
2605 | ||
2606 | #endif /* DEBUG_FS */ |