Commit | Line | Data |
---|---|---|
d2876d08 DB |
1 | #include <linux/kernel.h> |
2 | #include <linux/module.h> | |
ff77c352 | 3 | #include <linux/interrupt.h> |
d2876d08 DB |
4 | #include <linux/irq.h> |
5 | #include <linux/spinlock.h> | |
1a989d0f | 6 | #include <linux/list.h> |
d8f388d8 DB |
7 | #include <linux/device.h> |
8 | #include <linux/err.h> | |
9 | #include <linux/debugfs.h> | |
10 | #include <linux/seq_file.h> | |
11 | #include <linux/gpio.h> | |
391c970c | 12 | #include <linux/of_gpio.h> |
ff77c352 | 13 | #include <linux/idr.h> |
5a0e3ad6 | 14 | #include <linux/slab.h> |
7b199811 | 15 | #include <linux/acpi.h> |
53e7cac3 | 16 | #include <linux/gpio/driver.h> |
0a6d3158 | 17 | #include <linux/gpio/machine.h> |
c771c2f4 | 18 | #include <linux/pinctrl/consumer.h> |
ff2b1359 | 19 | #include <linux/idr.h> |
3c702e99 LW |
20 | #include <linux/cdev.h> |
21 | #include <linux/fs.h> | |
22 | #include <linux/uaccess.h> | |
23 | #include <uapi/linux/gpio.h> | |
d2876d08 | 24 | |
664e3e5a MW |
25 | #include "gpiolib.h" |
26 | ||
3f397c21 UKK |
27 | #define CREATE_TRACE_POINTS |
28 | #include <trace/events/gpio.h> | |
d2876d08 | 29 | |
79a9becd | 30 | /* Implementation infrastructure for GPIO interfaces. |
d2876d08 | 31 | * |
79a9becd AC |
32 | * The GPIO programming interface allows for inlining speed-critical |
33 | * get/set operations for common cases, so that access to SOC-integrated | |
34 | * GPIOs can sometimes cost only an instruction or two per bit. | |
d2876d08 DB |
35 | */ |
36 | ||
37 | ||
38 | /* When debugging, extend minimal trust to callers and platform code. | |
39 | * Also emit diagnostic messages that may help initial bringup, when | |
40 | * board setup or driver bugs are most common. | |
41 | * | |
42 | * Otherwise, minimize overhead in what may be bitbanging codepaths. | |
43 | */ | |
44 | #ifdef DEBUG | |
45 | #define extra_checks 1 | |
46 | #else | |
47 | #define extra_checks 0 | |
48 | #endif | |
49 | ||
ff2b1359 LW |
50 | /* Device and char device-related information */ |
51 | static DEFINE_IDA(gpio_ida); | |
3c702e99 LW |
52 | static dev_t gpio_devt; |
53 | #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */ | |
54 | static struct bus_type gpio_bus_type = { | |
55 | .name = "gpio", | |
56 | }; | |
ff2b1359 | 57 | |
d2876d08 DB |
58 | /* gpio_lock prevents conflicts during gpio_desc[] table updates. |
59 | * While any GPIO is requested, its gpio_chip is not removable; | |
60 | * each GPIO's "requested" flag serves as a lock and refcount. | |
61 | */ | |
0eb4c6c2 | 62 | DEFINE_SPINLOCK(gpio_lock); |
d2876d08 | 63 | |
bae48da2 AC |
64 | static DEFINE_MUTEX(gpio_lookup_lock); |
65 | static LIST_HEAD(gpio_lookup_list); | |
ff2b1359 | 66 | LIST_HEAD(gpio_devices); |
6d86750c JH |
67 | |
68 | static void gpiochip_free_hogs(struct gpio_chip *chip); | |
69 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); | |
70 | ||
71 | ||
d2876d08 DB |
72 | static inline void desc_set_label(struct gpio_desc *d, const char *label) |
73 | { | |
d2876d08 | 74 | d->label = label; |
d2876d08 DB |
75 | } |
76 | ||
372e722e AC |
77 | /** |
78 | * Convert a GPIO number to its descriptor | |
79 | */ | |
79a9becd | 80 | struct gpio_desc *gpio_to_desc(unsigned gpio) |
372e722e | 81 | { |
ff2b1359 | 82 | struct gpio_device *gdev; |
14e85c0e AC |
83 | unsigned long flags; |
84 | ||
85 | spin_lock_irqsave(&gpio_lock, flags); | |
86 | ||
ff2b1359 LW |
87 | list_for_each_entry(gdev, &gpio_devices, list) { |
88 | if (gdev->chip->base <= gpio && | |
89 | gdev->chip->base + gdev->chip->ngpio > gpio) { | |
14e85c0e | 90 | spin_unlock_irqrestore(&gpio_lock, flags); |
ff2b1359 | 91 | return &gdev->chip->desc[gpio - gdev->chip->base]; |
14e85c0e AC |
92 | } |
93 | } | |
94 | ||
95 | spin_unlock_irqrestore(&gpio_lock, flags); | |
96 | ||
0e9a5edf AC |
97 | if (!gpio_is_valid(gpio)) |
98 | WARN(1, "invalid GPIO %d\n", gpio); | |
99 | ||
14e85c0e | 100 | return NULL; |
372e722e | 101 | } |
79a9becd | 102 | EXPORT_SYMBOL_GPL(gpio_to_desc); |
372e722e | 103 | |
d468bf9e | 104 | /** |
bb1e88cc | 105 | * Get the GPIO descriptor corresponding to the given hw number for this chip. |
d468bf9e | 106 | */ |
bb1e88cc AC |
107 | struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, |
108 | u16 hwnum) | |
d468bf9e | 109 | { |
bb1e88cc | 110 | if (hwnum >= chip->ngpio) |
b7d0a28a | 111 | return ERR_PTR(-EINVAL); |
d468bf9e | 112 | |
bb1e88cc | 113 | return &chip->desc[hwnum]; |
d468bf9e | 114 | } |
372e722e AC |
115 | |
116 | /** | |
117 | * Convert a GPIO descriptor to the integer namespace. | |
118 | * This should disappear in the future but is needed since we still | |
119 | * use GPIO numbers for error messages and sysfs nodes | |
120 | */ | |
79a9becd | 121 | int desc_to_gpio(const struct gpio_desc *desc) |
372e722e | 122 | { |
14e85c0e | 123 | return desc->chip->base + (desc - &desc->chip->desc[0]); |
372e722e | 124 | } |
79a9becd | 125 | EXPORT_SYMBOL_GPL(desc_to_gpio); |
372e722e AC |
126 | |
127 | ||
79a9becd AC |
128 | /** |
129 | * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs | |
130 | * @desc: descriptor to return the chip of | |
131 | */ | |
132 | struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) | |
372e722e | 133 | { |
bcabdef1 | 134 | return desc ? desc->chip : NULL; |
372e722e | 135 | } |
79a9becd | 136 | EXPORT_SYMBOL_GPL(gpiod_to_chip); |
d2876d08 | 137 | |
8d0aab2f AV |
138 | /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ |
139 | static int gpiochip_find_base(int ngpio) | |
140 | { | |
ff2b1359 | 141 | struct gpio_device *gdev; |
83cabe33 | 142 | int base = ARCH_NR_GPIOS - ngpio; |
8d0aab2f | 143 | |
ff2b1359 | 144 | list_for_each_entry_reverse(gdev, &gpio_devices, list) { |
83cabe33 | 145 | /* found a free space? */ |
ff2b1359 | 146 | if (gdev->chip->base + gdev->chip->ngpio <= base) |
83cabe33 AC |
147 | break; |
148 | else | |
149 | /* nope, check the space right before the chip */ | |
ff2b1359 | 150 | base = gdev->chip->base - ngpio; |
8d0aab2f AV |
151 | } |
152 | ||
83cabe33 | 153 | if (gpio_is_valid(base)) { |
8d0aab2f | 154 | pr_debug("%s: found new base at %d\n", __func__, base); |
83cabe33 AC |
155 | return base; |
156 | } else { | |
157 | pr_err("%s: cannot find free range\n", __func__); | |
158 | return -ENOSPC; | |
169b6a7a | 159 | } |
169b6a7a AV |
160 | } |
161 | ||
79a9becd AC |
162 | /** |
163 | * gpiod_get_direction - return the current direction of a GPIO | |
164 | * @desc: GPIO to get the direction of | |
165 | * | |
166 | * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error. | |
167 | * | |
168 | * This function may sleep if gpiod_cansleep() is true. | |
169 | */ | |
8e53b0f1 | 170 | int gpiod_get_direction(struct gpio_desc *desc) |
80b0a602 MN |
171 | { |
172 | struct gpio_chip *chip; | |
372e722e | 173 | unsigned offset; |
80b0a602 MN |
174 | int status = -EINVAL; |
175 | ||
372e722e AC |
176 | chip = gpiod_to_chip(desc); |
177 | offset = gpio_chip_hwgpio(desc); | |
80b0a602 MN |
178 | |
179 | if (!chip->get_direction) | |
180 | return status; | |
181 | ||
372e722e | 182 | status = chip->get_direction(chip, offset); |
80b0a602 MN |
183 | if (status > 0) { |
184 | /* GPIOF_DIR_IN, or other positive */ | |
185 | status = 1; | |
8e53b0f1 | 186 | clear_bit(FLAG_IS_OUT, &desc->flags); |
80b0a602 MN |
187 | } |
188 | if (status == 0) { | |
189 | /* GPIOF_DIR_OUT */ | |
8e53b0f1 | 190 | set_bit(FLAG_IS_OUT, &desc->flags); |
80b0a602 MN |
191 | } |
192 | return status; | |
193 | } | |
79a9becd | 194 | EXPORT_SYMBOL_GPL(gpiod_get_direction); |
80b0a602 | 195 | |
1a989d0f AC |
196 | /* |
197 | * Add a new chip to the global chips list, keeping the list of chips sorted | |
ef7c7553 | 198 | * by range(means [base, base + ngpio - 1]) order. |
1a989d0f AC |
199 | * |
200 | * Return -EBUSY if the new chip overlaps with some other chip's integer | |
201 | * space. | |
202 | */ | |
ff2b1359 | 203 | static int gpiodev_add_to_list(struct gpio_device *gdev) |
1a989d0f | 204 | { |
ff2b1359 LW |
205 | struct gpio_device *iterator; |
206 | struct gpio_device *previous = NULL; | |
207 | ||
208 | if (!gdev->chip) | |
209 | return -EINVAL; | |
1a989d0f | 210 | |
ff2b1359 LW |
211 | if (list_empty(&gpio_devices)) { |
212 | list_add_tail(&gdev->list, &gpio_devices); | |
e28ecca6 | 213 | return 0; |
1a989d0f AC |
214 | } |
215 | ||
ff2b1359 LW |
216 | list_for_each_entry(iterator, &gpio_devices, list) { |
217 | /* | |
218 | * The list may contain dangling GPIO devices with no | |
219 | * live chip assigned. | |
220 | */ | |
221 | if (!iterator->chip) | |
222 | continue; | |
223 | if (iterator->chip->base >= | |
224 | gdev->chip->base + gdev->chip->ngpio) { | |
ef7c7553 BJZ |
225 | /* |
226 | * Iterator is the first GPIO chip so there is no | |
227 | * previous one | |
228 | */ | |
e28ecca6 | 229 | if (!previous) { |
ef7c7553 BJZ |
230 | goto found; |
231 | } else { | |
232 | /* | |
233 | * We found a valid range(means | |
234 | * [base, base + ngpio - 1]) between previous | |
235 | * and iterator chip. | |
236 | */ | |
ff2b1359 LW |
237 | if (previous->chip->base + previous->chip->ngpio |
238 | <= gdev->chip->base) | |
ef7c7553 BJZ |
239 | goto found; |
240 | } | |
1a989d0f | 241 | } |
ef7c7553 | 242 | previous = iterator; |
1a989d0f AC |
243 | } |
244 | ||
e28ecca6 SM |
245 | /* |
246 | * We are beyond the last chip in the list and iterator now | |
247 | * points to the head. | |
248 | * Let iterator point to the last chip in the list. | |
249 | */ | |
250 | ||
ff2b1359 LW |
251 | iterator = list_last_entry(&gpio_devices, struct gpio_device, list); |
252 | if (iterator->chip->base + iterator->chip->ngpio <= gdev->chip->base) { | |
253 | list_add(&gdev->list, &iterator->list); | |
96098df1 | 254 | return 0; |
1a989d0f AC |
255 | } |
256 | ||
ff2b1359 | 257 | dev_err(&gdev->dev, |
ef7c7553 BJZ |
258 | "GPIO integer space overlap, cannot add chip\n"); |
259 | return -EBUSY; | |
1a989d0f | 260 | |
ef7c7553 | 261 | found: |
ff2b1359 | 262 | list_add_tail(&gdev->list, &iterator->list); |
ef7c7553 | 263 | return 0; |
1a989d0f AC |
264 | } |
265 | ||
f881bab0 LW |
266 | /** |
267 | * Convert a GPIO name to its descriptor | |
268 | */ | |
269 | static struct gpio_desc *gpio_name_to_desc(const char * const name) | |
270 | { | |
ff2b1359 | 271 | struct gpio_device *gdev; |
f881bab0 LW |
272 | unsigned long flags; |
273 | ||
274 | spin_lock_irqsave(&gpio_lock, flags); | |
275 | ||
ff2b1359 | 276 | list_for_each_entry(gdev, &gpio_devices, list) { |
f881bab0 LW |
277 | int i; |
278 | ||
ff2b1359 LW |
279 | for (i = 0; i != gdev->chip->ngpio; ++i) { |
280 | struct gpio_desc *gpio = &gdev->chip->desc[i]; | |
f881bab0 | 281 | |
d06165b3 | 282 | if (!gpio->name || !name) |
f881bab0 LW |
283 | continue; |
284 | ||
285 | if (!strcmp(gpio->name, name)) { | |
286 | spin_unlock_irqrestore(&gpio_lock, flags); | |
287 | return gpio; | |
288 | } | |
289 | } | |
290 | } | |
291 | ||
292 | spin_unlock_irqrestore(&gpio_lock, flags); | |
293 | ||
294 | return NULL; | |
295 | } | |
296 | ||
5f3ca732 MP |
297 | /* |
298 | * Takes the names from gc->names and checks if they are all unique. If they | |
299 | * are, they are assigned to their gpio descriptors. | |
300 | * | |
ed37915c | 301 | * Warning if one of the names is already used for a different GPIO. |
5f3ca732 MP |
302 | */ |
303 | static int gpiochip_set_desc_names(struct gpio_chip *gc) | |
304 | { | |
305 | int i; | |
306 | ||
307 | if (!gc->names) | |
308 | return 0; | |
309 | ||
310 | /* First check all names if they are unique */ | |
311 | for (i = 0; i != gc->ngpio; ++i) { | |
312 | struct gpio_desc *gpio; | |
313 | ||
314 | gpio = gpio_name_to_desc(gc->names[i]); | |
f881bab0 | 315 | if (gpio) |
34ffd85d LW |
316 | dev_warn(&gc->gpiodev->dev, |
317 | "Detected name collision for GPIO name '%s'\n", | |
f881bab0 | 318 | gc->names[i]); |
5f3ca732 MP |
319 | } |
320 | ||
321 | /* Then add all names to the GPIO descriptors */ | |
322 | for (i = 0; i != gc->ngpio; ++i) | |
323 | gc->desc[i].name = gc->names[i]; | |
324 | ||
325 | return 0; | |
326 | } | |
327 | ||
3c702e99 LW |
328 | /** |
329 | * gpio_ioctl() - ioctl handler for the GPIO chardev | |
330 | */ | |
331 | static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) | |
332 | { | |
333 | struct gpio_device *gdev = filp->private_data; | |
334 | struct gpio_chip *chip = gdev->chip; | |
335 | int __user *ip = (int __user *)arg; | |
336 | struct gpiochip_info chipinfo; | |
337 | ||
338 | /* We fail any subsequent ioctl():s when the chip is gone */ | |
339 | if (!chip) | |
340 | return -ENODEV; | |
341 | ||
342 | if (cmd == GPIO_GET_CHIPINFO_IOCTL) { | |
343 | /* Fill in the struct and pass to userspace */ | |
344 | strncpy(chipinfo.name, dev_name(&gdev->dev), | |
345 | sizeof(chipinfo.name)); | |
346 | chipinfo.name[sizeof(chipinfo.name)-1] = '\0'; | |
347 | chipinfo.lines = chip->ngpio; | |
348 | if (copy_to_user(ip, &chipinfo, sizeof(chipinfo))) | |
349 | return -EFAULT; | |
350 | return 0; | |
351 | } | |
352 | return -EINVAL; | |
353 | } | |
354 | ||
355 | /** | |
356 | * gpio_chrdev_open() - open the chardev for ioctl operations | |
357 | * @inode: inode for this chardev | |
358 | * @filp: file struct for storing private data | |
359 | * Returns 0 on success | |
360 | */ | |
361 | static int gpio_chrdev_open(struct inode *inode, struct file *filp) | |
362 | { | |
363 | struct gpio_device *gdev = container_of(inode->i_cdev, | |
364 | struct gpio_device, chrdev); | |
365 | ||
366 | /* Fail on open if the backing gpiochip is gone */ | |
367 | if (!gdev || !gdev->chip) | |
368 | return -ENODEV; | |
369 | get_device(&gdev->dev); | |
370 | filp->private_data = gdev; | |
371 | return 0; | |
372 | } | |
373 | ||
374 | /** | |
375 | * gpio_chrdev_release() - close chardev after ioctl operations | |
376 | * @inode: inode for this chardev | |
377 | * @filp: file struct for storing private data | |
378 | * Returns 0 on success | |
379 | */ | |
380 | static int gpio_chrdev_release(struct inode *inode, struct file *filp) | |
381 | { | |
382 | struct gpio_device *gdev = container_of(inode->i_cdev, | |
383 | struct gpio_device, chrdev); | |
384 | ||
385 | if (!gdev) | |
386 | return -ENODEV; | |
387 | put_device(&gdev->dev); | |
388 | return 0; | |
389 | } | |
390 | ||
391 | ||
392 | static const struct file_operations gpio_fileops = { | |
393 | .release = gpio_chrdev_release, | |
394 | .open = gpio_chrdev_open, | |
395 | .owner = THIS_MODULE, | |
396 | .llseek = noop_llseek, | |
397 | .unlocked_ioctl = gpio_ioctl, | |
398 | .compat_ioctl = gpio_ioctl, | |
399 | }; | |
400 | ||
ff2b1359 LW |
401 | static void gpiodevice_release(struct device *dev) |
402 | { | |
403 | struct gpio_device *gdev = dev_get_drvdata(dev); | |
404 | ||
3c702e99 | 405 | cdev_del(&gdev->chrdev); |
ff2b1359 LW |
406 | list_del(&gdev->list); |
407 | ida_simple_remove(&gpio_ida, gdev->id); | |
9efd9e69 | 408 | kfree(gdev); |
ff2b1359 LW |
409 | } |
410 | ||
d2876d08 | 411 | /** |
b08ea35a | 412 | * gpiochip_add_data() - register a gpio_chip |
d2876d08 | 413 | * @chip: the chip to register, with chip->base initialized |
14e85c0e | 414 | * Context: potentially before irqs will work |
d2876d08 DB |
415 | * |
416 | * Returns a negative errno if the chip can't be registered, such as | |
417 | * because the chip->base is invalid or already associated with a | |
418 | * different chip. Otherwise it returns zero as a success code. | |
8d0aab2f | 419 | * |
b08ea35a | 420 | * When gpiochip_add_data() is called very early during boot, so that GPIOs |
c88402c2 | 421 | * can be freely used, the chip->parent device must be registered before |
d8f388d8 DB |
422 | * the gpio framework's arch_initcall(). Otherwise sysfs initialization |
423 | * for GPIOs will fail rudely. | |
424 | * | |
8d0aab2f AV |
425 | * If chip->base is negative, this requests dynamic assignment of |
426 | * a range of valid GPIOs. | |
d2876d08 | 427 | */ |
b08ea35a | 428 | int gpiochip_add_data(struct gpio_chip *chip, void *data) |
d2876d08 DB |
429 | { |
430 | unsigned long flags; | |
431 | int status = 0; | |
ff2b1359 | 432 | unsigned i; |
8d0aab2f | 433 | int base = chip->base; |
14e85c0e | 434 | struct gpio_desc *descs; |
ff2b1359 | 435 | struct gpio_device *gdev; |
d2876d08 | 436 | |
ff2b1359 LW |
437 | /* |
438 | * First: allocate and populate the internal stat container, and | |
439 | * set up the struct device. | |
440 | */ | |
441 | gdev = kmalloc(sizeof(*gdev), GFP_KERNEL); | |
442 | if (!gdev) | |
14e85c0e | 443 | return -ENOMEM; |
3c702e99 | 444 | gdev->dev.bus = &gpio_bus_type; |
ff2b1359 LW |
445 | gdev->chip = chip; |
446 | chip->gpiodev = gdev; | |
447 | if (chip->parent) { | |
448 | gdev->dev.parent = chip->parent; | |
449 | gdev->dev.of_node = chip->parent->of_node; | |
450 | } else { | |
451 | #ifdef CONFIG_OF_GPIO | |
452 | /* If the gpiochip has an assigned OF node this takes precedence */ | |
453 | if (chip->of_node) | |
454 | gdev->dev.of_node = chip->of_node; | |
455 | #endif | |
456 | } | |
457 | gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL); | |
458 | if (gdev->id < 0) { | |
459 | status = gdev->id; | |
460 | goto err_free_gdev; | |
461 | } | |
462 | dev_set_name(&gdev->dev, "gpiochip%d", gdev->id); | |
463 | device_initialize(&gdev->dev); | |
464 | dev_set_drvdata(&gdev->dev, gdev); | |
465 | if (chip->parent && chip->parent->driver) | |
466 | gdev->owner = chip->parent->driver->owner; | |
467 | else if (chip->owner) | |
468 | /* TODO: remove chip->owner */ | |
469 | gdev->owner = chip->owner; | |
470 | else | |
471 | gdev->owner = THIS_MODULE; | |
d2876d08 | 472 | |
ff2b1359 LW |
473 | /* FIXME: devm_kcalloc() these and move to gpio_device */ |
474 | descs = kcalloc(chip->ngpio, sizeof(descs[0]), GFP_KERNEL); | |
475 | if (!descs) { | |
476 | status = -ENOMEM; | |
477 | goto err_free_gdev; | |
478 | } | |
479 | ||
480 | /* FIXME: move driver data into gpio_device dev_set_drvdata() */ | |
b08ea35a LW |
481 | chip->data = data; |
482 | ||
5ed41cc4 BJZ |
483 | if (chip->ngpio == 0) { |
484 | chip_err(chip, "tried to insert a GPIO chip with zero lines\n"); | |
ff2b1359 LW |
485 | status = -EINVAL; |
486 | goto err_free_descs; | |
5ed41cc4 BJZ |
487 | } |
488 | ||
d2876d08 DB |
489 | spin_lock_irqsave(&gpio_lock, flags); |
490 | ||
8d0aab2f AV |
491 | if (base < 0) { |
492 | base = gpiochip_find_base(chip->ngpio); | |
493 | if (base < 0) { | |
494 | status = base; | |
225fce83 JH |
495 | spin_unlock_irqrestore(&gpio_lock, flags); |
496 | goto err_free_descs; | |
8d0aab2f AV |
497 | } |
498 | chip->base = base; | |
499 | } | |
500 | ||
ff2b1359 | 501 | status = gpiodev_add_to_list(gdev); |
05aa5203 JH |
502 | if (status) { |
503 | spin_unlock_irqrestore(&gpio_lock, flags); | |
504 | goto err_free_descs; | |
505 | } | |
1a989d0f | 506 | |
ff2b1359 LW |
507 | for (i = 0; i < chip->ngpio; i++) { |
508 | struct gpio_desc *desc = &descs[i]; | |
05aa5203 | 509 | |
ff2b1359 | 510 | /* REVISIT: maybe a pointer to gpio_device is better */ |
05aa5203 JH |
511 | desc->chip = chip; |
512 | ||
513 | /* REVISIT: most hardware initializes GPIOs as inputs (often | |
514 | * with pullups enabled) so power usage is minimized. Linux | |
515 | * code should set the gpio direction first thing; but until | |
516 | * it does, and in case chip->get_direction is not set, we may | |
517 | * expose the wrong direction in sysfs. | |
518 | */ | |
519 | desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0; | |
d2876d08 | 520 | } |
14e85c0e AC |
521 | chip->desc = descs; |
522 | ||
3bae4811 ZG |
523 | spin_unlock_irqrestore(&gpio_lock, flags); |
524 | ||
f23f1516 | 525 | #ifdef CONFIG_PINCTRL |
ff2b1359 | 526 | /* FIXME: move pin ranges to gpio_device */ |
f23f1516 SH |
527 | INIT_LIST_HEAD(&chip->pin_ranges); |
528 | #endif | |
529 | ||
5f3ca732 MP |
530 | status = gpiochip_set_desc_names(chip); |
531 | if (status) | |
532 | goto err_remove_from_list; | |
533 | ||
28355f81 TV |
534 | status = of_gpiochip_add(chip); |
535 | if (status) | |
536 | goto err_remove_chip; | |
537 | ||
664e3e5a | 538 | acpi_gpiochip_add(chip); |
391c970c | 539 | |
3c702e99 LW |
540 | /* |
541 | * By first adding the chardev, and then adding the device, | |
542 | * we get a device node entry in sysfs under | |
543 | * /sys/bus/gpio/devices/gpiochipN/dev that can be used for | |
544 | * coldplug of device nodes and other udev business. | |
545 | */ | |
546 | cdev_init(&gdev->chrdev, &gpio_fileops); | |
547 | gdev->chrdev.owner = THIS_MODULE; | |
548 | gdev->chrdev.kobj.parent = &gdev->dev.kobj; | |
549 | gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id); | |
550 | status = cdev_add(&gdev->chrdev, gdev->dev.devt, 1); | |
551 | if (status < 0) | |
552 | chip_warn(chip, "failed to add char device %d:%d\n", | |
553 | MAJOR(gpio_devt), gdev->id); | |
554 | else | |
555 | chip_dbg(chip, "added GPIO chardev (%d:%d)\n", | |
556 | MAJOR(gpio_devt), gdev->id); | |
ff2b1359 | 557 | status = device_add(&gdev->dev); |
225fce83 | 558 | if (status) |
3c702e99 | 559 | goto err_remove_chardev; |
cedb1881 | 560 | |
ff2b1359 LW |
561 | status = gpiochip_sysfs_register(chip); |
562 | if (status) | |
563 | goto err_remove_device; | |
564 | ||
565 | /* From this point, the .release() function cleans up gpio_device */ | |
566 | gdev->dev.release = gpiodevice_release; | |
567 | get_device(&gdev->dev); | |
7589e59f | 568 | pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__, |
64842aad GL |
569 | chip->base, chip->base + chip->ngpio - 1, |
570 | chip->label ? : "generic"); | |
571 | ||
cedb1881 | 572 | return 0; |
3bae4811 | 573 | |
ff2b1359 LW |
574 | err_remove_device: |
575 | device_del(&gdev->dev); | |
3c702e99 LW |
576 | err_remove_chardev: |
577 | cdev_del(&gdev->chrdev); | |
225fce83 JH |
578 | err_remove_chip: |
579 | acpi_gpiochip_remove(chip); | |
6d86750c | 580 | gpiochip_free_hogs(chip); |
225fce83 | 581 | of_gpiochip_remove(chip); |
5f3ca732 | 582 | err_remove_from_list: |
225fce83 | 583 | spin_lock_irqsave(&gpio_lock, flags); |
ff2b1359 | 584 | list_del(&gdev->list); |
3bae4811 | 585 | spin_unlock_irqrestore(&gpio_lock, flags); |
05aa5203 | 586 | chip->desc = NULL; |
225fce83 | 587 | err_free_descs: |
14e85c0e | 588 | kfree(descs); |
ff2b1359 LW |
589 | err_free_gdev: |
590 | ida_simple_remove(&gpio_ida, gdev->id); | |
591 | kfree(gdev); | |
d2876d08 | 592 | /* failures here can mean systems won't boot... */ |
7589e59f | 593 | pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__, |
cedb1881 AV |
594 | chip->base, chip->base + chip->ngpio - 1, |
595 | chip->label ? : "generic"); | |
d2876d08 DB |
596 | return status; |
597 | } | |
b08ea35a | 598 | EXPORT_SYMBOL_GPL(gpiochip_add_data); |
d2876d08 DB |
599 | |
600 | /** | |
601 | * gpiochip_remove() - unregister a gpio_chip | |
602 | * @chip: the chip to unregister | |
603 | * | |
604 | * A gpio_chip with any GPIOs still requested may not be removed. | |
605 | */ | |
e1db1706 | 606 | void gpiochip_remove(struct gpio_chip *chip) |
d2876d08 | 607 | { |
ff2b1359 | 608 | struct gpio_device *gdev = chip->gpiodev; |
fab28b89 | 609 | struct gpio_desc *desc; |
d2876d08 | 610 | unsigned long flags; |
d2876d08 | 611 | unsigned id; |
fab28b89 | 612 | bool requested = false; |
d2876d08 | 613 | |
ff2b1359 LW |
614 | /* Numb the device, cancelling all outstanding operations */ |
615 | gdev->chip = NULL; | |
01cca93a | 616 | |
ff2b1359 LW |
617 | /* FIXME: should the legacy sysfs handling be moved to gpio_device? */ |
618 | gpiochip_sysfs_unregister(chip); | |
00acc3dc | 619 | gpiochip_irqchip_remove(chip); |
6072b9dc | 620 | acpi_gpiochip_remove(chip); |
9ef0d6f7 | 621 | gpiochip_remove_pin_ranges(chip); |
f625d460 | 622 | gpiochip_free_hogs(chip); |
391c970c AV |
623 | of_gpiochip_remove(chip); |
624 | ||
6798acaa | 625 | spin_lock_irqsave(&gpio_lock, flags); |
6c0b4e6c | 626 | for (id = 0; id < chip->ngpio; id++) { |
fab28b89 JH |
627 | desc = &chip->desc[id]; |
628 | desc->chip = NULL; | |
629 | if (test_bit(FLAG_REQUESTED, &desc->flags)) | |
630 | requested = true; | |
d2876d08 | 631 | } |
d2876d08 | 632 | spin_unlock_irqrestore(&gpio_lock, flags); |
14e85c0e | 633 | |
fab28b89 | 634 | if (requested) |
34ffd85d | 635 | dev_crit(&chip->gpiodev->dev, |
58383c78 | 636 | "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n"); |
fab28b89 | 637 | |
ff2b1359 | 638 | /* FIXME: need to be moved to gpio_device and held there */ |
14e85c0e AC |
639 | kfree(chip->desc); |
640 | chip->desc = NULL; | |
ff2b1359 LW |
641 | |
642 | /* | |
643 | * The gpiochip side puts its use of the device to rest here: | |
644 | * if there are no userspace clients, the chardev and device will | |
645 | * be removed, else it will be dangling until the last user is | |
646 | * gone. | |
647 | */ | |
648 | put_device(&gdev->dev); | |
d2876d08 DB |
649 | } |
650 | EXPORT_SYMBOL_GPL(gpiochip_remove); | |
651 | ||
594fa265 GL |
652 | /** |
653 | * gpiochip_find() - iterator for locating a specific gpio_chip | |
654 | * @data: data to pass to match function | |
655 | * @callback: Callback function to check gpio_chip | |
656 | * | |
657 | * Similar to bus_find_device. It returns a reference to a gpio_chip as | |
658 | * determined by a user supplied @match callback. The callback should return | |
659 | * 0 if the device doesn't match and non-zero if it does. If the callback is | |
660 | * non-zero, this function will return to the caller and not iterate over any | |
661 | * more gpio_chips. | |
662 | */ | |
07ce8ec7 | 663 | struct gpio_chip *gpiochip_find(void *data, |
6e2cf651 | 664 | int (*match)(struct gpio_chip *chip, |
3d0f7cf0 | 665 | void *data)) |
594fa265 | 666 | { |
ff2b1359 | 667 | struct gpio_device *gdev; |
125eef96 | 668 | struct gpio_chip *chip; |
594fa265 | 669 | unsigned long flags; |
594fa265 GL |
670 | |
671 | spin_lock_irqsave(&gpio_lock, flags); | |
ff2b1359 LW |
672 | list_for_each_entry(gdev, &gpio_devices, list) |
673 | if (match(gdev->chip, data)) | |
594fa265 | 674 | break; |
125eef96 AC |
675 | |
676 | /* No match? */ | |
ff2b1359 | 677 | if (&gdev->list == &gpio_devices) |
125eef96 | 678 | chip = NULL; |
ff2b1359 LW |
679 | else |
680 | chip = gdev->chip; | |
681 | ||
594fa265 GL |
682 | spin_unlock_irqrestore(&gpio_lock, flags); |
683 | ||
684 | return chip; | |
685 | } | |
8fa0c9bf | 686 | EXPORT_SYMBOL_GPL(gpiochip_find); |
d2876d08 | 687 | |
79697ef9 AC |
688 | static int gpiochip_match_name(struct gpio_chip *chip, void *data) |
689 | { | |
690 | const char *name = data; | |
691 | ||
692 | return !strcmp(chip->label, name); | |
693 | } | |
694 | ||
695 | static struct gpio_chip *find_chip_by_name(const char *name) | |
696 | { | |
697 | return gpiochip_find((void *)name, gpiochip_match_name); | |
698 | } | |
699 | ||
14250520 LW |
700 | #ifdef CONFIG_GPIOLIB_IRQCHIP |
701 | ||
702 | /* | |
703 | * The following is irqchip helper code for gpiochips. | |
704 | */ | |
705 | ||
706 | /** | |
3f97d5fc LW |
707 | * gpiochip_set_chained_irqchip() - sets a chained irqchip to a gpiochip |
708 | * @gpiochip: the gpiochip to set the irqchip chain to | |
709 | * @irqchip: the irqchip to chain to the gpiochip | |
14250520 LW |
710 | * @parent_irq: the irq number corresponding to the parent IRQ for this |
711 | * chained irqchip | |
712 | * @parent_handler: the parent interrupt handler for the accumulated IRQ | |
3f97d5fc LW |
713 | * coming out of the gpiochip. If the interrupt is nested rather than |
714 | * cascaded, pass NULL in this handler argument | |
14250520 LW |
715 | */ |
716 | void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, | |
717 | struct irq_chip *irqchip, | |
718 | int parent_irq, | |
719 | irq_flow_handler_t parent_handler) | |
720 | { | |
83141a77 LW |
721 | unsigned int offset; |
722 | ||
83141a77 LW |
723 | if (!gpiochip->irqdomain) { |
724 | chip_err(gpiochip, "called %s before setting up irqchip\n", | |
725 | __func__); | |
1c8732bb LW |
726 | return; |
727 | } | |
728 | ||
3f97d5fc LW |
729 | if (parent_handler) { |
730 | if (gpiochip->can_sleep) { | |
731 | chip_err(gpiochip, | |
732 | "you cannot have chained interrupts on a " | |
733 | "chip that may sleep\n"); | |
734 | return; | |
735 | } | |
3f97d5fc LW |
736 | /* |
737 | * The parent irqchip is already using the chip_data for this | |
738 | * irqchip, so our callbacks simply use the handler_data. | |
739 | */ | |
f7f87753 TG |
740 | irq_set_chained_handler_and_data(parent_irq, parent_handler, |
741 | gpiochip); | |
25e4fe92 DES |
742 | |
743 | gpiochip->irq_parent = parent_irq; | |
3f97d5fc | 744 | } |
83141a77 LW |
745 | |
746 | /* Set the parent IRQ for all affected IRQs */ | |
747 | for (offset = 0; offset < gpiochip->ngpio; offset++) | |
748 | irq_set_parent(irq_find_mapping(gpiochip->irqdomain, offset), | |
749 | parent_irq); | |
14250520 LW |
750 | } |
751 | EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip); | |
752 | ||
753 | /** | |
754 | * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip | |
755 | * @d: the irqdomain used by this irqchip | |
756 | * @irq: the global irq number used by this GPIO irqchip irq | |
757 | * @hwirq: the local IRQ/GPIO line offset on this gpiochip | |
758 | * | |
759 | * This function will set up the mapping for a certain IRQ line on a | |
760 | * gpiochip by assigning the gpiochip as chip data, and using the irqchip | |
761 | * stored inside the gpiochip. | |
762 | */ | |
763 | static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, | |
764 | irq_hw_number_t hwirq) | |
765 | { | |
766 | struct gpio_chip *chip = d->host_data; | |
767 | ||
14250520 | 768 | irq_set_chip_data(irq, chip); |
a0a8bcf4 GS |
769 | /* |
770 | * This lock class tells lockdep that GPIO irqs are in a different | |
771 | * category than their parents, so it won't report false recursion. | |
772 | */ | |
773 | irq_set_lockdep_class(irq, chip->lock_key); | |
7633fb95 | 774 | irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler); |
1c8732bb | 775 | /* Chips that can sleep need nested thread handlers */ |
295494af | 776 | if (chip->can_sleep && !chip->irq_not_threaded) |
1c8732bb | 777 | irq_set_nested_thread(irq, 1); |
14250520 | 778 | irq_set_noprobe(irq); |
23393d49 | 779 | |
1333b90f LW |
780 | /* |
781 | * No set-up of the hardware will happen if IRQ_TYPE_NONE | |
782 | * is passed as default type. | |
783 | */ | |
784 | if (chip->irq_default_type != IRQ_TYPE_NONE) | |
785 | irq_set_irq_type(irq, chip->irq_default_type); | |
14250520 LW |
786 | |
787 | return 0; | |
788 | } | |
789 | ||
c3626fde LW |
790 | static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) |
791 | { | |
1c8732bb LW |
792 | struct gpio_chip *chip = d->host_data; |
793 | ||
1c8732bb LW |
794 | if (chip->can_sleep) |
795 | irq_set_nested_thread(irq, 0); | |
c3626fde LW |
796 | irq_set_chip_and_handler(irq, NULL, NULL); |
797 | irq_set_chip_data(irq, NULL); | |
798 | } | |
799 | ||
14250520 LW |
800 | static const struct irq_domain_ops gpiochip_domain_ops = { |
801 | .map = gpiochip_irq_map, | |
c3626fde | 802 | .unmap = gpiochip_irq_unmap, |
14250520 LW |
803 | /* Virtually all GPIO irqchips are twocell:ed */ |
804 | .xlate = irq_domain_xlate_twocell, | |
805 | }; | |
806 | ||
807 | static int gpiochip_irq_reqres(struct irq_data *d) | |
808 | { | |
809 | struct gpio_chip *chip = irq_data_get_irq_chip_data(d); | |
810 | ||
ff2b1359 | 811 | if (!try_module_get(chip->gpiodev->owner)) |
5b76e79c GS |
812 | return -ENODEV; |
813 | ||
e3a2e878 | 814 | if (gpiochip_lock_as_irq(chip, d->hwirq)) { |
14250520 LW |
815 | chip_err(chip, |
816 | "unable to lock HW IRQ %lu for IRQ\n", | |
817 | d->hwirq); | |
ff2b1359 | 818 | module_put(chip->gpiodev->owner); |
14250520 LW |
819 | return -EINVAL; |
820 | } | |
821 | return 0; | |
822 | } | |
823 | ||
824 | static void gpiochip_irq_relres(struct irq_data *d) | |
825 | { | |
826 | struct gpio_chip *chip = irq_data_get_irq_chip_data(d); | |
827 | ||
e3a2e878 | 828 | gpiochip_unlock_as_irq(chip, d->hwirq); |
ff2b1359 | 829 | module_put(chip->gpiodev->owner); |
14250520 LW |
830 | } |
831 | ||
832 | static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) | |
833 | { | |
834 | return irq_find_mapping(chip->irqdomain, offset); | |
835 | } | |
836 | ||
837 | /** | |
838 | * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip | |
839 | * @gpiochip: the gpiochip to remove the irqchip from | |
840 | * | |
841 | * This is called only from gpiochip_remove() | |
842 | */ | |
843 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) | |
844 | { | |
c3626fde LW |
845 | unsigned int offset; |
846 | ||
afa82fab MW |
847 | acpi_gpiochip_free_interrupts(gpiochip); |
848 | ||
25e4fe92 DES |
849 | if (gpiochip->irq_parent) { |
850 | irq_set_chained_handler(gpiochip->irq_parent, NULL); | |
851 | irq_set_handler_data(gpiochip->irq_parent, NULL); | |
852 | } | |
853 | ||
c3626fde LW |
854 | /* Remove all IRQ mappings and delete the domain */ |
855 | if (gpiochip->irqdomain) { | |
856 | for (offset = 0; offset < gpiochip->ngpio; offset++) | |
e3893386 GS |
857 | irq_dispose_mapping( |
858 | irq_find_mapping(gpiochip->irqdomain, offset)); | |
14250520 | 859 | irq_domain_remove(gpiochip->irqdomain); |
c3626fde | 860 | } |
14250520 LW |
861 | |
862 | if (gpiochip->irqchip) { | |
863 | gpiochip->irqchip->irq_request_resources = NULL; | |
864 | gpiochip->irqchip->irq_release_resources = NULL; | |
865 | gpiochip->irqchip = NULL; | |
866 | } | |
867 | } | |
868 | ||
869 | /** | |
870 | * gpiochip_irqchip_add() - adds an irqchip to a gpiochip | |
871 | * @gpiochip: the gpiochip to add the irqchip to | |
872 | * @irqchip: the irqchip to add to the gpiochip | |
873 | * @first_irq: if not dynamically assigned, the base (first) IRQ to | |
874 | * allocate gpiochip irqs from | |
875 | * @handler: the irq handler to use (often a predefined irq core function) | |
1333b90f LW |
876 | * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE |
877 | * to have the core avoid setting up any default type in the hardware. | |
a0a8bcf4 | 878 | * @lock_key: lockdep class |
14250520 LW |
879 | * |
880 | * This function closely associates a certain irqchip with a certain | |
881 | * gpiochip, providing an irq domain to translate the local IRQs to | |
882 | * global irqs in the gpiolib core, and making sure that the gpiochip | |
883 | * is passed as chip data to all related functions. Driver callbacks | |
09dd5f9e | 884 | * need to use gpiochip_get_data() to get their local state containers back |
14250520 LW |
885 | * from the gpiochip passed as chip data. An irqdomain will be stored |
886 | * in the gpiochip that shall be used by the driver to handle IRQ number | |
887 | * translation. The gpiochip will need to be initialized and registered | |
888 | * before calling this function. | |
889 | * | |
c3626fde LW |
890 | * This function will handle two cell:ed simple IRQs and assumes all |
891 | * the pins on the gpiochip can generate a unique IRQ. Everything else | |
14250520 LW |
892 | * need to be open coded. |
893 | */ | |
a0a8bcf4 GS |
894 | int _gpiochip_irqchip_add(struct gpio_chip *gpiochip, |
895 | struct irq_chip *irqchip, | |
896 | unsigned int first_irq, | |
897 | irq_flow_handler_t handler, | |
898 | unsigned int type, | |
899 | struct lock_class_key *lock_key) | |
14250520 LW |
900 | { |
901 | struct device_node *of_node; | |
902 | unsigned int offset; | |
c3626fde | 903 | unsigned irq_base = 0; |
14250520 LW |
904 | |
905 | if (!gpiochip || !irqchip) | |
906 | return -EINVAL; | |
907 | ||
58383c78 | 908 | if (!gpiochip->parent) { |
14250520 LW |
909 | pr_err("missing gpiochip .dev parent pointer\n"); |
910 | return -EINVAL; | |
911 | } | |
58383c78 | 912 | of_node = gpiochip->parent->of_node; |
14250520 LW |
913 | #ifdef CONFIG_OF_GPIO |
914 | /* | |
20a8a968 | 915 | * If the gpiochip has an assigned OF node this takes precedence |
c88402c2 BJZ |
916 | * FIXME: get rid of this and use gpiochip->parent->of_node |
917 | * everywhere | |
14250520 LW |
918 | */ |
919 | if (gpiochip->of_node) | |
920 | of_node = gpiochip->of_node; | |
921 | #endif | |
922 | gpiochip->irqchip = irqchip; | |
923 | gpiochip->irq_handler = handler; | |
924 | gpiochip->irq_default_type = type; | |
925 | gpiochip->to_irq = gpiochip_to_irq; | |
a0a8bcf4 | 926 | gpiochip->lock_key = lock_key; |
14250520 LW |
927 | gpiochip->irqdomain = irq_domain_add_simple(of_node, |
928 | gpiochip->ngpio, first_irq, | |
929 | &gpiochip_domain_ops, gpiochip); | |
930 | if (!gpiochip->irqdomain) { | |
931 | gpiochip->irqchip = NULL; | |
932 | return -EINVAL; | |
933 | } | |
8b67a1f0 RV |
934 | |
935 | /* | |
936 | * It is possible for a driver to override this, but only if the | |
937 | * alternative functions are both implemented. | |
938 | */ | |
939 | if (!irqchip->irq_request_resources && | |
940 | !irqchip->irq_release_resources) { | |
941 | irqchip->irq_request_resources = gpiochip_irq_reqres; | |
942 | irqchip->irq_release_resources = gpiochip_irq_relres; | |
943 | } | |
14250520 LW |
944 | |
945 | /* | |
946 | * Prepare the mapping since the irqchip shall be orthogonal to | |
947 | * any gpiochip calls. If the first_irq was zero, this is | |
948 | * necessary to allocate descriptors for all IRQs. | |
949 | */ | |
c3626fde LW |
950 | for (offset = 0; offset < gpiochip->ngpio; offset++) { |
951 | irq_base = irq_create_mapping(gpiochip->irqdomain, offset); | |
952 | if (offset == 0) | |
953 | /* | |
954 | * Store the base into the gpiochip to be used when | |
955 | * unmapping the irqs. | |
956 | */ | |
957 | gpiochip->irq_base = irq_base; | |
958 | } | |
14250520 | 959 | |
afa82fab MW |
960 | acpi_gpiochip_request_interrupts(gpiochip); |
961 | ||
14250520 LW |
962 | return 0; |
963 | } | |
a0a8bcf4 | 964 | EXPORT_SYMBOL_GPL(_gpiochip_irqchip_add); |
14250520 LW |
965 | |
966 | #else /* CONFIG_GPIOLIB_IRQCHIP */ | |
967 | ||
968 | static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {} | |
969 | ||
970 | #endif /* CONFIG_GPIOLIB_IRQCHIP */ | |
971 | ||
c771c2f4 JG |
972 | /** |
973 | * gpiochip_generic_request() - request the gpio function for a pin | |
974 | * @chip: the gpiochip owning the GPIO | |
975 | * @offset: the offset of the GPIO to request for GPIO function | |
976 | */ | |
977 | int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset) | |
978 | { | |
979 | return pinctrl_request_gpio(chip->base + offset); | |
980 | } | |
981 | EXPORT_SYMBOL_GPL(gpiochip_generic_request); | |
982 | ||
983 | /** | |
984 | * gpiochip_generic_free() - free the gpio function from a pin | |
985 | * @chip: the gpiochip to request the gpio function for | |
986 | * @offset: the offset of the GPIO to free from GPIO function | |
987 | */ | |
988 | void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset) | |
989 | { | |
990 | pinctrl_free_gpio(chip->base + offset); | |
991 | } | |
992 | EXPORT_SYMBOL_GPL(gpiochip_generic_free); | |
993 | ||
f23f1516 | 994 | #ifdef CONFIG_PINCTRL |
165adc9c | 995 | |
586a87e6 CR |
996 | /** |
997 | * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping | |
998 | * @chip: the gpiochip to add the range for | |
d32651f6 | 999 | * @pctldev: the pin controller to map to |
586a87e6 CR |
1000 | * @gpio_offset: the start offset in the current gpio_chip number space |
1001 | * @pin_group: name of the pin group inside the pin controller | |
1002 | */ | |
1003 | int gpiochip_add_pingroup_range(struct gpio_chip *chip, | |
1004 | struct pinctrl_dev *pctldev, | |
1005 | unsigned int gpio_offset, const char *pin_group) | |
1006 | { | |
1007 | struct gpio_pin_range *pin_range; | |
1008 | int ret; | |
1009 | ||
1010 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); | |
1011 | if (!pin_range) { | |
1a2a99c6 | 1012 | chip_err(chip, "failed to allocate pin ranges\n"); |
586a87e6 CR |
1013 | return -ENOMEM; |
1014 | } | |
1015 | ||
1016 | /* Use local offset as range ID */ | |
1017 | pin_range->range.id = gpio_offset; | |
1018 | pin_range->range.gc = chip; | |
1019 | pin_range->range.name = chip->label; | |
1020 | pin_range->range.base = chip->base + gpio_offset; | |
1021 | pin_range->pctldev = pctldev; | |
1022 | ||
1023 | ret = pinctrl_get_group_pins(pctldev, pin_group, | |
1024 | &pin_range->range.pins, | |
1025 | &pin_range->range.npins); | |
61c6375d MN |
1026 | if (ret < 0) { |
1027 | kfree(pin_range); | |
586a87e6 | 1028 | return ret; |
61c6375d | 1029 | } |
586a87e6 CR |
1030 | |
1031 | pinctrl_add_gpio_range(pctldev, &pin_range->range); | |
1032 | ||
1a2a99c6 AS |
1033 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n", |
1034 | gpio_offset, gpio_offset + pin_range->range.npins - 1, | |
586a87e6 CR |
1035 | pinctrl_dev_get_devname(pctldev), pin_group); |
1036 | ||
1037 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
1038 | ||
1039 | return 0; | |
1040 | } | |
1041 | EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); | |
1042 | ||
3f0f8670 LW |
1043 | /** |
1044 | * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping | |
1045 | * @chip: the gpiochip to add the range for | |
1046 | * @pinctrl_name: the dev_name() of the pin controller to map to | |
316511c0 LW |
1047 | * @gpio_offset: the start offset in the current gpio_chip number space |
1048 | * @pin_offset: the start offset in the pin controller number space | |
3f0f8670 LW |
1049 | * @npins: the number of pins from the offset of each pin space (GPIO and |
1050 | * pin controller) to accumulate in this range | |
1051 | */ | |
1e63d7b9 | 1052 | int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, |
316511c0 | 1053 | unsigned int gpio_offset, unsigned int pin_offset, |
3f0f8670 | 1054 | unsigned int npins) |
f23f1516 SH |
1055 | { |
1056 | struct gpio_pin_range *pin_range; | |
b4d4b1f0 | 1057 | int ret; |
f23f1516 | 1058 | |
3f0f8670 | 1059 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); |
f23f1516 | 1060 | if (!pin_range) { |
1a2a99c6 | 1061 | chip_err(chip, "failed to allocate pin ranges\n"); |
1e63d7b9 | 1062 | return -ENOMEM; |
f23f1516 SH |
1063 | } |
1064 | ||
3f0f8670 | 1065 | /* Use local offset as range ID */ |
316511c0 | 1066 | pin_range->range.id = gpio_offset; |
3f0f8670 | 1067 | pin_range->range.gc = chip; |
f23f1516 | 1068 | pin_range->range.name = chip->label; |
316511c0 LW |
1069 | pin_range->range.base = chip->base + gpio_offset; |
1070 | pin_range->range.pin_base = pin_offset; | |
f23f1516 | 1071 | pin_range->range.npins = npins; |
192c369c | 1072 | pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, |
f23f1516 | 1073 | &pin_range->range); |
8f23ca1a | 1074 | if (IS_ERR(pin_range->pctldev)) { |
b4d4b1f0 | 1075 | ret = PTR_ERR(pin_range->pctldev); |
1a2a99c6 | 1076 | chip_err(chip, "could not create pin range\n"); |
3f0f8670 | 1077 | kfree(pin_range); |
b4d4b1f0 | 1078 | return ret; |
3f0f8670 | 1079 | } |
1a2a99c6 AS |
1080 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n", |
1081 | gpio_offset, gpio_offset + npins - 1, | |
316511c0 LW |
1082 | pinctl_name, |
1083 | pin_offset, pin_offset + npins - 1); | |
f23f1516 SH |
1084 | |
1085 | list_add_tail(&pin_range->node, &chip->pin_ranges); | |
1e63d7b9 LW |
1086 | |
1087 | return 0; | |
f23f1516 | 1088 | } |
165adc9c | 1089 | EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); |
f23f1516 | 1090 | |
3f0f8670 LW |
1091 | /** |
1092 | * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings | |
1093 | * @chip: the chip to remove all the mappings for | |
1094 | */ | |
f23f1516 SH |
1095 | void gpiochip_remove_pin_ranges(struct gpio_chip *chip) |
1096 | { | |
1097 | struct gpio_pin_range *pin_range, *tmp; | |
1098 | ||
1099 | list_for_each_entry_safe(pin_range, tmp, &chip->pin_ranges, node) { | |
1100 | list_del(&pin_range->node); | |
1101 | pinctrl_remove_gpio_range(pin_range->pctldev, | |
1102 | &pin_range->range); | |
3f0f8670 | 1103 | kfree(pin_range); |
f23f1516 SH |
1104 | } |
1105 | } | |
165adc9c LW |
1106 | EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); |
1107 | ||
1108 | #endif /* CONFIG_PINCTRL */ | |
f23f1516 | 1109 | |
d2876d08 DB |
1110 | /* These "optional" allocation calls help prevent drivers from stomping |
1111 | * on each other, and help provide better diagnostics in debugfs. | |
1112 | * They're called even less than the "set direction" calls. | |
1113 | */ | |
77c2d792 | 1114 | static int __gpiod_request(struct gpio_desc *desc, const char *label) |
d2876d08 | 1115 | { |
77c2d792 MW |
1116 | struct gpio_chip *chip = desc->chip; |
1117 | int status; | |
d2876d08 DB |
1118 | unsigned long flags; |
1119 | ||
bcabdef1 AC |
1120 | spin_lock_irqsave(&gpio_lock, flags); |
1121 | ||
d2876d08 | 1122 | /* NOTE: gpio_request() can be called in early boot, |
35e8bb51 | 1123 | * before IRQs are enabled, for non-sleeping (SOC) GPIOs. |
d2876d08 DB |
1124 | */ |
1125 | ||
1126 | if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { | |
1127 | desc_set_label(desc, label ? : "?"); | |
1128 | status = 0; | |
438d8908 | 1129 | } else { |
d2876d08 | 1130 | status = -EBUSY; |
7460db56 | 1131 | goto done; |
35e8bb51 DB |
1132 | } |
1133 | ||
1134 | if (chip->request) { | |
1135 | /* chip->request may sleep */ | |
1136 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 1137 | status = chip->request(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
1138 | spin_lock_irqsave(&gpio_lock, flags); |
1139 | ||
1140 | if (status < 0) { | |
1141 | desc_set_label(desc, NULL); | |
35e8bb51 | 1142 | clear_bit(FLAG_REQUESTED, &desc->flags); |
80b0a602 | 1143 | goto done; |
35e8bb51 | 1144 | } |
438d8908 | 1145 | } |
80b0a602 MN |
1146 | if (chip->get_direction) { |
1147 | /* chip->get_direction may sleep */ | |
1148 | spin_unlock_irqrestore(&gpio_lock, flags); | |
372e722e | 1149 | gpiod_get_direction(desc); |
80b0a602 MN |
1150 | spin_lock_irqsave(&gpio_lock, flags); |
1151 | } | |
77c2d792 | 1152 | done: |
923b93e4 LP |
1153 | if (status < 0) { |
1154 | /* Clear flags that might have been set by the caller before | |
1155 | * requesting the GPIO. | |
1156 | */ | |
1157 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
1158 | clear_bit(FLAG_OPEN_DRAIN, &desc->flags); | |
1159 | clear_bit(FLAG_OPEN_SOURCE, &desc->flags); | |
1160 | } | |
77c2d792 MW |
1161 | spin_unlock_irqrestore(&gpio_lock, flags); |
1162 | return status; | |
1163 | } | |
1164 | ||
0eb4c6c2 | 1165 | int gpiod_request(struct gpio_desc *desc, const char *label) |
77c2d792 MW |
1166 | { |
1167 | int status = -EPROBE_DEFER; | |
1168 | struct gpio_chip *chip; | |
1169 | ||
1170 | if (!desc) { | |
1171 | pr_warn("%s: invalid GPIO\n", __func__); | |
1172 | return -EINVAL; | |
1173 | } | |
1174 | ||
1175 | chip = desc->chip; | |
1176 | if (!chip) | |
1177 | goto done; | |
1178 | ||
ff2b1359 | 1179 | if (try_module_get(chip->gpiodev->owner)) { |
77c2d792 MW |
1180 | status = __gpiod_request(desc, label); |
1181 | if (status < 0) | |
ff2b1359 | 1182 | module_put(chip->gpiodev->owner); |
77c2d792 MW |
1183 | } |
1184 | ||
d2876d08 DB |
1185 | done: |
1186 | if (status) | |
7589e59f | 1187 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
77c2d792 | 1188 | |
d2876d08 DB |
1189 | return status; |
1190 | } | |
372e722e | 1191 | |
77c2d792 | 1192 | static bool __gpiod_free(struct gpio_desc *desc) |
d2876d08 | 1193 | { |
77c2d792 | 1194 | bool ret = false; |
d2876d08 | 1195 | unsigned long flags; |
35e8bb51 | 1196 | struct gpio_chip *chip; |
d2876d08 | 1197 | |
3d599d1c UKK |
1198 | might_sleep(); |
1199 | ||
372e722e | 1200 | gpiod_unexport(desc); |
d8f388d8 | 1201 | |
d2876d08 DB |
1202 | spin_lock_irqsave(&gpio_lock, flags); |
1203 | ||
35e8bb51 DB |
1204 | chip = desc->chip; |
1205 | if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { | |
1206 | if (chip->free) { | |
1207 | spin_unlock_irqrestore(&gpio_lock, flags); | |
9c4ba946 | 1208 | might_sleep_if(chip->can_sleep); |
372e722e | 1209 | chip->free(chip, gpio_chip_hwgpio(desc)); |
35e8bb51 DB |
1210 | spin_lock_irqsave(&gpio_lock, flags); |
1211 | } | |
d2876d08 | 1212 | desc_set_label(desc, NULL); |
07697461 | 1213 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); |
35e8bb51 | 1214 | clear_bit(FLAG_REQUESTED, &desc->flags); |
aca5ce14 | 1215 | clear_bit(FLAG_OPEN_DRAIN, &desc->flags); |
25553ff0 | 1216 | clear_bit(FLAG_OPEN_SOURCE, &desc->flags); |
f625d460 | 1217 | clear_bit(FLAG_IS_HOGGED, &desc->flags); |
77c2d792 MW |
1218 | ret = true; |
1219 | } | |
d2876d08 DB |
1220 | |
1221 | spin_unlock_irqrestore(&gpio_lock, flags); | |
77c2d792 MW |
1222 | return ret; |
1223 | } | |
1224 | ||
0eb4c6c2 | 1225 | void gpiod_free(struct gpio_desc *desc) |
77c2d792 MW |
1226 | { |
1227 | if (desc && __gpiod_free(desc)) | |
ff2b1359 | 1228 | module_put(desc->chip->gpiodev->owner); |
77c2d792 MW |
1229 | else |
1230 | WARN_ON(extra_checks); | |
d2876d08 | 1231 | } |
372e722e | 1232 | |
d2876d08 DB |
1233 | /** |
1234 | * gpiochip_is_requested - return string iff signal was requested | |
1235 | * @chip: controller managing the signal | |
1236 | * @offset: of signal within controller's 0..(ngpio - 1) range | |
1237 | * | |
1238 | * Returns NULL if the GPIO is not currently requested, else a string. | |
9c8318ff AC |
1239 | * The string returned is the label passed to gpio_request(); if none has been |
1240 | * passed it is a meaningless, non-NULL constant. | |
d2876d08 DB |
1241 | * |
1242 | * This function is for use by GPIO controller drivers. The label can | |
1243 | * help with diagnostics, and knowing that the signal is used as a GPIO | |
1244 | * can help avoid accidentally multiplexing it to another controller. | |
1245 | */ | |
1246 | const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) | |
1247 | { | |
6c0b4e6c | 1248 | struct gpio_desc *desc; |
d2876d08 | 1249 | |
48b5953e | 1250 | if (offset >= chip->ngpio) |
d2876d08 | 1251 | return NULL; |
6c0b4e6c AC |
1252 | |
1253 | desc = &chip->desc[offset]; | |
1254 | ||
372e722e | 1255 | if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) |
d2876d08 | 1256 | return NULL; |
372e722e | 1257 | return desc->label; |
d2876d08 DB |
1258 | } |
1259 | EXPORT_SYMBOL_GPL(gpiochip_is_requested); | |
1260 | ||
77c2d792 MW |
1261 | /** |
1262 | * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor | |
1263 | * @desc: GPIO descriptor to request | |
1264 | * @label: label for the GPIO | |
1265 | * | |
1266 | * Function allows GPIO chip drivers to request and use their own GPIO | |
1267 | * descriptors via gpiolib API. Difference to gpiod_request() is that this | |
1268 | * function will not increase reference count of the GPIO chip module. This | |
1269 | * allows the GPIO chip module to be unloaded as needed (we assume that the | |
1270 | * GPIO chip driver handles freeing the GPIOs it has requested). | |
1271 | */ | |
abdc08a3 AC |
1272 | struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum, |
1273 | const char *label) | |
77c2d792 | 1274 | { |
abdc08a3 AC |
1275 | struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum); |
1276 | int err; | |
77c2d792 | 1277 | |
abdc08a3 AC |
1278 | if (IS_ERR(desc)) { |
1279 | chip_err(chip, "failed to get GPIO descriptor\n"); | |
1280 | return desc; | |
1281 | } | |
1282 | ||
1283 | err = __gpiod_request(desc, label); | |
1284 | if (err < 0) | |
1285 | return ERR_PTR(err); | |
77c2d792 | 1286 | |
abdc08a3 | 1287 | return desc; |
77c2d792 | 1288 | } |
f7d4ad98 | 1289 | EXPORT_SYMBOL_GPL(gpiochip_request_own_desc); |
77c2d792 MW |
1290 | |
1291 | /** | |
1292 | * gpiochip_free_own_desc - Free GPIO requested by the chip driver | |
1293 | * @desc: GPIO descriptor to free | |
1294 | * | |
1295 | * Function frees the given GPIO requested previously with | |
1296 | * gpiochip_request_own_desc(). | |
1297 | */ | |
1298 | void gpiochip_free_own_desc(struct gpio_desc *desc) | |
1299 | { | |
1300 | if (desc) | |
1301 | __gpiod_free(desc); | |
1302 | } | |
f7d4ad98 | 1303 | EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); |
d2876d08 DB |
1304 | |
1305 | /* Drivers MUST set GPIO direction before making get/set calls. In | |
1306 | * some cases this is done in early boot, before IRQs are enabled. | |
1307 | * | |
1308 | * As a rule these aren't called more than once (except for drivers | |
1309 | * using the open-drain emulation idiom) so these are natural places | |
1310 | * to accumulate extra debugging checks. Note that we can't (yet) | |
1311 | * rely on gpio_request() having been called beforehand. | |
1312 | */ | |
1313 | ||
79a9becd AC |
1314 | /** |
1315 | * gpiod_direction_input - set the GPIO direction to input | |
1316 | * @desc: GPIO to set to input | |
1317 | * | |
1318 | * Set the direction of the passed GPIO to input, such as gpiod_get_value() can | |
1319 | * be called safely on it. | |
1320 | * | |
1321 | * Return 0 in case of success, else an error code. | |
1322 | */ | |
1323 | int gpiod_direction_input(struct gpio_desc *desc) | |
d2876d08 | 1324 | { |
d2876d08 | 1325 | struct gpio_chip *chip; |
d2876d08 DB |
1326 | int status = -EINVAL; |
1327 | ||
be1a4b13 | 1328 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1329 | pr_warn("%s: invalid GPIO\n", __func__); |
1330 | return -EINVAL; | |
1331 | } | |
1332 | ||
be1a4b13 LW |
1333 | chip = desc->chip; |
1334 | if (!chip->get || !chip->direction_input) { | |
6424de5a MB |
1335 | gpiod_warn(desc, |
1336 | "%s: missing get() or direction_input() operations\n", | |
7589e59f | 1337 | __func__); |
be1a4b13 LW |
1338 | return -EIO; |
1339 | } | |
1340 | ||
d82da797 | 1341 | status = chip->direction_input(chip, gpio_chip_hwgpio(desc)); |
d2876d08 DB |
1342 | if (status == 0) |
1343 | clear_bit(FLAG_IS_OUT, &desc->flags); | |
3f397c21 | 1344 | |
372e722e | 1345 | trace_gpio_direction(desc_to_gpio(desc), 1, status); |
d82da797 | 1346 | |
d2876d08 DB |
1347 | return status; |
1348 | } | |
79a9becd | 1349 | EXPORT_SYMBOL_GPL(gpiod_direction_input); |
372e722e | 1350 | |
ef70bbe1 | 1351 | static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) |
d2876d08 | 1352 | { |
d2876d08 | 1353 | struct gpio_chip *chip; |
d2876d08 DB |
1354 | int status = -EINVAL; |
1355 | ||
d468bf9e LW |
1356 | /* GPIOs used for IRQs shall not be set as output */ |
1357 | if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) { | |
1358 | gpiod_err(desc, | |
1359 | "%s: tried to set a GPIO tied to an IRQ as output\n", | |
1360 | __func__); | |
1361 | return -EIO; | |
1362 | } | |
1363 | ||
aca5ce14 LD |
1364 | /* Open drain pin should not be driven to 1 */ |
1365 | if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
372e722e | 1366 | return gpiod_direction_input(desc); |
aca5ce14 | 1367 | |
25553ff0 LD |
1368 | /* Open source pin should not be driven to 0 */ |
1369 | if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
372e722e | 1370 | return gpiod_direction_input(desc); |
25553ff0 | 1371 | |
be1a4b13 LW |
1372 | chip = desc->chip; |
1373 | if (!chip->set || !chip->direction_output) { | |
6424de5a MB |
1374 | gpiod_warn(desc, |
1375 | "%s: missing set() or direction_output() operations\n", | |
1376 | __func__); | |
be1a4b13 LW |
1377 | return -EIO; |
1378 | } | |
1379 | ||
d82da797 | 1380 | status = chip->direction_output(chip, gpio_chip_hwgpio(desc), value); |
d2876d08 DB |
1381 | if (status == 0) |
1382 | set_bit(FLAG_IS_OUT, &desc->flags); | |
372e722e AC |
1383 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
1384 | trace_gpio_direction(desc_to_gpio(desc), 0, status); | |
d2876d08 DB |
1385 | return status; |
1386 | } | |
ef70bbe1 PZ |
1387 | |
1388 | /** | |
1389 | * gpiod_direction_output_raw - set the GPIO direction to output | |
1390 | * @desc: GPIO to set to output | |
1391 | * @value: initial output value of the GPIO | |
1392 | * | |
1393 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
1394 | * be called safely on it. The initial value of the output must be specified | |
1395 | * as raw value on the physical line without regard for the ACTIVE_LOW status. | |
1396 | * | |
1397 | * Return 0 in case of success, else an error code. | |
1398 | */ | |
1399 | int gpiod_direction_output_raw(struct gpio_desc *desc, int value) | |
1400 | { | |
1401 | if (!desc || !desc->chip) { | |
1402 | pr_warn("%s: invalid GPIO\n", __func__); | |
1403 | return -EINVAL; | |
1404 | } | |
1405 | return _gpiod_direction_output_raw(desc, value); | |
1406 | } | |
1407 | EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); | |
1408 | ||
1409 | /** | |
90df4fe0 | 1410 | * gpiod_direction_output - set the GPIO direction to output |
ef70bbe1 PZ |
1411 | * @desc: GPIO to set to output |
1412 | * @value: initial output value of the GPIO | |
1413 | * | |
1414 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can | |
1415 | * be called safely on it. The initial value of the output must be specified | |
1416 | * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1417 | * account. | |
1418 | * | |
1419 | * Return 0 in case of success, else an error code. | |
1420 | */ | |
1421 | int gpiod_direction_output(struct gpio_desc *desc, int value) | |
1422 | { | |
1423 | if (!desc || !desc->chip) { | |
1424 | pr_warn("%s: invalid GPIO\n", __func__); | |
1425 | return -EINVAL; | |
1426 | } | |
1427 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1428 | value = !value; | |
1429 | return _gpiod_direction_output_raw(desc, value); | |
1430 | } | |
79a9becd | 1431 | EXPORT_SYMBOL_GPL(gpiod_direction_output); |
d2876d08 | 1432 | |
c4b5be98 | 1433 | /** |
79a9becd | 1434 | * gpiod_set_debounce - sets @debounce time for a @gpio |
c4b5be98 FB |
1435 | * @gpio: the gpio to set debounce time |
1436 | * @debounce: debounce time is microseconds | |
65d87656 LW |
1437 | * |
1438 | * returns -ENOTSUPP if the controller does not support setting | |
1439 | * debounce. | |
c4b5be98 | 1440 | */ |
79a9becd | 1441 | int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) |
c4b5be98 | 1442 | { |
c4b5be98 | 1443 | struct gpio_chip *chip; |
c4b5be98 | 1444 | |
be1a4b13 | 1445 | if (!desc || !desc->chip) { |
bcabdef1 AC |
1446 | pr_warn("%s: invalid GPIO\n", __func__); |
1447 | return -EINVAL; | |
1448 | } | |
1449 | ||
c4b5be98 | 1450 | chip = desc->chip; |
be1a4b13 | 1451 | if (!chip->set || !chip->set_debounce) { |
6424de5a MB |
1452 | gpiod_dbg(desc, |
1453 | "%s: missing set() or set_debounce() operations\n", | |
1454 | __func__); | |
65d87656 | 1455 | return -ENOTSUPP; |
be1a4b13 LW |
1456 | } |
1457 | ||
d82da797 | 1458 | return chip->set_debounce(chip, gpio_chip_hwgpio(desc), debounce); |
c4b5be98 | 1459 | } |
79a9becd | 1460 | EXPORT_SYMBOL_GPL(gpiod_set_debounce); |
372e722e | 1461 | |
79a9becd AC |
1462 | /** |
1463 | * gpiod_is_active_low - test whether a GPIO is active-low or not | |
1464 | * @desc: the gpio descriptor to test | |
1465 | * | |
1466 | * Returns 1 if the GPIO is active-low, 0 otherwise. | |
1467 | */ | |
1468 | int gpiod_is_active_low(const struct gpio_desc *desc) | |
372e722e | 1469 | { |
79a9becd | 1470 | return test_bit(FLAG_ACTIVE_LOW, &desc->flags); |
372e722e | 1471 | } |
79a9becd | 1472 | EXPORT_SYMBOL_GPL(gpiod_is_active_low); |
d2876d08 DB |
1473 | |
1474 | /* I/O calls are only valid after configuration completed; the relevant | |
1475 | * "is this a valid GPIO" error checks should already have been done. | |
1476 | * | |
1477 | * "Get" operations are often inlinable as reading a pin value register, | |
1478 | * and masking the relevant bit in that register. | |
1479 | * | |
1480 | * When "set" operations are inlinable, they involve writing that mask to | |
1481 | * one register to set a low value, or a different register to set it high. | |
1482 | * Otherwise locking is needed, so there may be little value to inlining. | |
1483 | * | |
1484 | *------------------------------------------------------------------------ | |
1485 | * | |
1486 | * IMPORTANT!!! The hot paths -- get/set value -- assume that callers | |
1487 | * have requested the GPIO. That can include implicit requesting by | |
1488 | * a direction setting call. Marking a gpio as requested locks its chip | |
1489 | * in memory, guaranteeing that these table lookups need no more locking | |
1490 | * and that gpiochip_remove() will fail. | |
1491 | * | |
1492 | * REVISIT when debugging, consider adding some instrumentation to ensure | |
1493 | * that the GPIO was actually requested. | |
1494 | */ | |
1495 | ||
e20538b8 | 1496 | static int _gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 DB |
1497 | { |
1498 | struct gpio_chip *chip; | |
372e722e | 1499 | int offset; |
e20538b8 | 1500 | int value; |
d2876d08 | 1501 | |
372e722e AC |
1502 | chip = desc->chip; |
1503 | offset = gpio_chip_hwgpio(desc); | |
e20538b8 | 1504 | value = chip->get ? chip->get(chip, offset) : -EIO; |
723a6303 | 1505 | value = value < 0 ? value : !!value; |
372e722e | 1506 | trace_gpio_value(desc_to_gpio(desc), 1, value); |
3f397c21 | 1507 | return value; |
d2876d08 | 1508 | } |
372e722e | 1509 | |
d2876d08 | 1510 | /** |
79a9becd AC |
1511 | * gpiod_get_raw_value() - return a gpio's raw value |
1512 | * @desc: gpio whose value will be returned | |
d2876d08 | 1513 | * |
79a9becd | 1514 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding |
e20538b8 | 1515 | * its ACTIVE_LOW status, or negative errno on failure. |
79a9becd AC |
1516 | * |
1517 | * This function should be called from contexts where we cannot sleep, and will | |
1518 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1519 | */ |
79a9becd | 1520 | int gpiod_get_raw_value(const struct gpio_desc *desc) |
d2876d08 | 1521 | { |
bcabdef1 AC |
1522 | if (!desc) |
1523 | return 0; | |
e4e449e8 | 1524 | /* Should be using gpio_get_value_cansleep() */ |
d8e0ac08 | 1525 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 1526 | return _gpiod_get_raw_value(desc); |
d2876d08 | 1527 | } |
79a9becd | 1528 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value); |
372e722e | 1529 | |
79a9becd AC |
1530 | /** |
1531 | * gpiod_get_value() - return a gpio's value | |
1532 | * @desc: gpio whose value will be returned | |
1533 | * | |
1534 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
e20538b8 | 1535 | * account, or negative errno on failure. |
79a9becd AC |
1536 | * |
1537 | * This function should be called from contexts where we cannot sleep, and will | |
1538 | * complain if the GPIO chip functions potentially sleep. | |
1539 | */ | |
1540 | int gpiod_get_value(const struct gpio_desc *desc) | |
372e722e | 1541 | { |
79a9becd AC |
1542 | int value; |
1543 | if (!desc) | |
1544 | return 0; | |
1545 | /* Should be using gpio_get_value_cansleep() */ | |
1546 | WARN_ON(desc->chip->can_sleep); | |
1547 | ||
1548 | value = _gpiod_get_raw_value(desc); | |
e20538b8 BA |
1549 | if (value < 0) |
1550 | return value; | |
1551 | ||
79a9becd AC |
1552 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
1553 | value = !value; | |
1554 | ||
1555 | return value; | |
372e722e | 1556 | } |
79a9becd | 1557 | EXPORT_SYMBOL_GPL(gpiod_get_value); |
d2876d08 | 1558 | |
aca5ce14 LD |
1559 | /* |
1560 | * _gpio_set_open_drain_value() - Set the open drain gpio's value. | |
79a9becd | 1561 | * @desc: gpio descriptor whose state need to be set. |
20a8a968 | 1562 | * @value: Non-zero for setting it HIGH otherwise it will set to LOW. |
aca5ce14 | 1563 | */ |
23600969 | 1564 | static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value) |
aca5ce14 LD |
1565 | { |
1566 | int err = 0; | |
372e722e AC |
1567 | struct gpio_chip *chip = desc->chip; |
1568 | int offset = gpio_chip_hwgpio(desc); | |
1569 | ||
aca5ce14 | 1570 | if (value) { |
372e722e | 1571 | err = chip->direction_input(chip, offset); |
aca5ce14 | 1572 | if (!err) |
372e722e | 1573 | clear_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 1574 | } else { |
372e722e | 1575 | err = chip->direction_output(chip, offset, 0); |
aca5ce14 | 1576 | if (!err) |
372e722e | 1577 | set_bit(FLAG_IS_OUT, &desc->flags); |
aca5ce14 | 1578 | } |
372e722e | 1579 | trace_gpio_direction(desc_to_gpio(desc), value, err); |
aca5ce14 | 1580 | if (err < 0) |
6424de5a MB |
1581 | gpiod_err(desc, |
1582 | "%s: Error in set_value for open drain err %d\n", | |
1583 | __func__, err); | |
aca5ce14 LD |
1584 | } |
1585 | ||
25553ff0 | 1586 | /* |
79a9becd AC |
1587 | * _gpio_set_open_source_value() - Set the open source gpio's value. |
1588 | * @desc: gpio descriptor whose state need to be set. | |
20a8a968 | 1589 | * @value: Non-zero for setting it HIGH otherwise it will set to LOW. |
25553ff0 | 1590 | */ |
23600969 | 1591 | static void _gpio_set_open_source_value(struct gpio_desc *desc, bool value) |
25553ff0 LD |
1592 | { |
1593 | int err = 0; | |
372e722e AC |
1594 | struct gpio_chip *chip = desc->chip; |
1595 | int offset = gpio_chip_hwgpio(desc); | |
1596 | ||
25553ff0 | 1597 | if (value) { |
372e722e | 1598 | err = chip->direction_output(chip, offset, 1); |
25553ff0 | 1599 | if (!err) |
372e722e | 1600 | set_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 1601 | } else { |
372e722e | 1602 | err = chip->direction_input(chip, offset); |
25553ff0 | 1603 | if (!err) |
372e722e | 1604 | clear_bit(FLAG_IS_OUT, &desc->flags); |
25553ff0 | 1605 | } |
372e722e | 1606 | trace_gpio_direction(desc_to_gpio(desc), !value, err); |
25553ff0 | 1607 | if (err < 0) |
6424de5a MB |
1608 | gpiod_err(desc, |
1609 | "%s: Error in set_value for open source err %d\n", | |
1610 | __func__, err); | |
25553ff0 LD |
1611 | } |
1612 | ||
23600969 | 1613 | static void _gpiod_set_raw_value(struct gpio_desc *desc, bool value) |
d2876d08 DB |
1614 | { |
1615 | struct gpio_chip *chip; | |
1616 | ||
372e722e | 1617 | chip = desc->chip; |
372e722e AC |
1618 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
1619 | if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) | |
1620 | _gpio_set_open_drain_value(desc, value); | |
1621 | else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) | |
1622 | _gpio_set_open_source_value(desc, value); | |
aca5ce14 | 1623 | else |
372e722e AC |
1624 | chip->set(chip, gpio_chip_hwgpio(desc), value); |
1625 | } | |
1626 | ||
5f424243 RI |
1627 | /* |
1628 | * set multiple outputs on the same chip; | |
1629 | * use the chip's set_multiple function if available; | |
1630 | * otherwise set the outputs sequentially; | |
1631 | * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word | |
1632 | * defines which outputs are to be changed | |
1633 | * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word | |
1634 | * defines the values the outputs specified by mask are to be set to | |
1635 | */ | |
1636 | static void gpio_chip_set_multiple(struct gpio_chip *chip, | |
1637 | unsigned long *mask, unsigned long *bits) | |
1638 | { | |
1639 | if (chip->set_multiple) { | |
1640 | chip->set_multiple(chip, mask, bits); | |
1641 | } else { | |
1642 | int i; | |
1643 | for (i = 0; i < chip->ngpio; i++) { | |
1644 | if (mask[BIT_WORD(i)] == 0) { | |
1645 | /* no more set bits in this mask word; | |
1646 | * skip ahead to the next word */ | |
1647 | i = (BIT_WORD(i) + 1) * BITS_PER_LONG - 1; | |
1648 | continue; | |
1649 | } | |
1650 | /* set outputs if the corresponding mask bit is set */ | |
38e003f4 | 1651 | if (__test_and_clear_bit(i, mask)) |
5f424243 | 1652 | chip->set(chip, i, test_bit(i, bits)); |
5f424243 RI |
1653 | } |
1654 | } | |
1655 | } | |
1656 | ||
3fff99bc RI |
1657 | static void gpiod_set_array_value_priv(bool raw, bool can_sleep, |
1658 | unsigned int array_size, | |
1659 | struct gpio_desc **desc_array, | |
1660 | int *value_array) | |
5f424243 RI |
1661 | { |
1662 | int i = 0; | |
1663 | ||
1664 | while (i < array_size) { | |
1665 | struct gpio_chip *chip = desc_array[i]->chip; | |
1666 | unsigned long mask[BITS_TO_LONGS(chip->ngpio)]; | |
1667 | unsigned long bits[BITS_TO_LONGS(chip->ngpio)]; | |
1668 | int count = 0; | |
1669 | ||
38e003f4 | 1670 | if (!can_sleep) |
5f424243 | 1671 | WARN_ON(chip->can_sleep); |
38e003f4 | 1672 | |
5f424243 RI |
1673 | memset(mask, 0, sizeof(mask)); |
1674 | do { | |
1675 | struct gpio_desc *desc = desc_array[i]; | |
1676 | int hwgpio = gpio_chip_hwgpio(desc); | |
1677 | int value = value_array[i]; | |
1678 | ||
1679 | if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1680 | value = !value; | |
1681 | trace_gpio_value(desc_to_gpio(desc), 0, value); | |
1682 | /* | |
1683 | * collect all normal outputs belonging to the same chip | |
1684 | * open drain and open source outputs are set individually | |
1685 | */ | |
1686 | if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { | |
38e003f4 | 1687 | _gpio_set_open_drain_value(desc, value); |
5f424243 RI |
1688 | } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) { |
1689 | _gpio_set_open_source_value(desc, value); | |
1690 | } else { | |
1691 | __set_bit(hwgpio, mask); | |
38e003f4 | 1692 | if (value) |
5f424243 | 1693 | __set_bit(hwgpio, bits); |
38e003f4 | 1694 | else |
5f424243 | 1695 | __clear_bit(hwgpio, bits); |
5f424243 RI |
1696 | count++; |
1697 | } | |
1698 | i++; | |
1699 | } while ((i < array_size) && (desc_array[i]->chip == chip)); | |
1700 | /* push collected bits to outputs */ | |
38e003f4 | 1701 | if (count != 0) |
5f424243 | 1702 | gpio_chip_set_multiple(chip, mask, bits); |
5f424243 RI |
1703 | } |
1704 | } | |
1705 | ||
d2876d08 | 1706 | /** |
79a9becd AC |
1707 | * gpiod_set_raw_value() - assign a gpio's raw value |
1708 | * @desc: gpio whose value will be assigned | |
d2876d08 | 1709 | * @value: value to assign |
d2876d08 | 1710 | * |
79a9becd AC |
1711 | * Set the raw value of the GPIO, i.e. the value of its physical line without |
1712 | * regard for its ACTIVE_LOW status. | |
1713 | * | |
1714 | * This function should be called from contexts where we cannot sleep, and will | |
1715 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1716 | */ |
79a9becd | 1717 | void gpiod_set_raw_value(struct gpio_desc *desc, int value) |
372e722e | 1718 | { |
bcabdef1 AC |
1719 | if (!desc) |
1720 | return; | |
e4e449e8 | 1721 | /* Should be using gpio_set_value_cansleep() */ |
d8e0ac08 | 1722 | WARN_ON(desc->chip->can_sleep); |
79a9becd | 1723 | _gpiod_set_raw_value(desc, value); |
d2876d08 | 1724 | } |
79a9becd | 1725 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value); |
d2876d08 DB |
1726 | |
1727 | /** | |
79a9becd AC |
1728 | * gpiod_set_value() - assign a gpio's value |
1729 | * @desc: gpio whose value will be assigned | |
1730 | * @value: value to assign | |
1731 | * | |
1732 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1733 | * account | |
d2876d08 | 1734 | * |
79a9becd AC |
1735 | * This function should be called from contexts where we cannot sleep, and will |
1736 | * complain if the GPIO chip functions potentially sleep. | |
d2876d08 | 1737 | */ |
79a9becd | 1738 | void gpiod_set_value(struct gpio_desc *desc, int value) |
d2876d08 | 1739 | { |
bcabdef1 | 1740 | if (!desc) |
79a9becd AC |
1741 | return; |
1742 | /* Should be using gpio_set_value_cansleep() */ | |
1743 | WARN_ON(desc->chip->can_sleep); | |
1744 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1745 | value = !value; | |
1746 | _gpiod_set_raw_value(desc, value); | |
372e722e | 1747 | } |
79a9becd | 1748 | EXPORT_SYMBOL_GPL(gpiod_set_value); |
d2876d08 | 1749 | |
5f424243 | 1750 | /** |
3fff99bc | 1751 | * gpiod_set_raw_array_value() - assign values to an array of GPIOs |
5f424243 RI |
1752 | * @array_size: number of elements in the descriptor / value arrays |
1753 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1754 | * @value_array: array of values to assign | |
1755 | * | |
1756 | * Set the raw values of the GPIOs, i.e. the values of the physical lines | |
1757 | * without regard for their ACTIVE_LOW status. | |
1758 | * | |
1759 | * This function should be called from contexts where we cannot sleep, and will | |
1760 | * complain if the GPIO chip functions potentially sleep. | |
1761 | */ | |
3fff99bc | 1762 | void gpiod_set_raw_array_value(unsigned int array_size, |
5f424243 RI |
1763 | struct gpio_desc **desc_array, int *value_array) |
1764 | { | |
1765 | if (!desc_array) | |
1766 | return; | |
3fff99bc RI |
1767 | gpiod_set_array_value_priv(true, false, array_size, desc_array, |
1768 | value_array); | |
5f424243 | 1769 | } |
3fff99bc | 1770 | EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value); |
5f424243 RI |
1771 | |
1772 | /** | |
3fff99bc | 1773 | * gpiod_set_array_value() - assign values to an array of GPIOs |
5f424243 RI |
1774 | * @array_size: number of elements in the descriptor / value arrays |
1775 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1776 | * @value_array: array of values to assign | |
1777 | * | |
1778 | * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status | |
1779 | * into account. | |
1780 | * | |
1781 | * This function should be called from contexts where we cannot sleep, and will | |
1782 | * complain if the GPIO chip functions potentially sleep. | |
1783 | */ | |
3fff99bc RI |
1784 | void gpiod_set_array_value(unsigned int array_size, |
1785 | struct gpio_desc **desc_array, int *value_array) | |
5f424243 RI |
1786 | { |
1787 | if (!desc_array) | |
1788 | return; | |
3fff99bc RI |
1789 | gpiod_set_array_value_priv(false, false, array_size, desc_array, |
1790 | value_array); | |
5f424243 | 1791 | } |
3fff99bc | 1792 | EXPORT_SYMBOL_GPL(gpiod_set_array_value); |
5f424243 | 1793 | |
d2876d08 | 1794 | /** |
79a9becd AC |
1795 | * gpiod_cansleep() - report whether gpio value access may sleep |
1796 | * @desc: gpio to check | |
d2876d08 | 1797 | * |
d2876d08 | 1798 | */ |
79a9becd | 1799 | int gpiod_cansleep(const struct gpio_desc *desc) |
372e722e | 1800 | { |
bcabdef1 AC |
1801 | if (!desc) |
1802 | return 0; | |
372e722e | 1803 | return desc->chip->can_sleep; |
d2876d08 | 1804 | } |
79a9becd | 1805 | EXPORT_SYMBOL_GPL(gpiod_cansleep); |
d2876d08 | 1806 | |
0f6d504e | 1807 | /** |
79a9becd AC |
1808 | * gpiod_to_irq() - return the IRQ corresponding to a GPIO |
1809 | * @desc: gpio whose IRQ will be returned (already requested) | |
0f6d504e | 1810 | * |
79a9becd AC |
1811 | * Return the IRQ corresponding to the passed GPIO, or an error code in case of |
1812 | * error. | |
0f6d504e | 1813 | */ |
79a9becd | 1814 | int gpiod_to_irq(const struct gpio_desc *desc) |
0f6d504e DB |
1815 | { |
1816 | struct gpio_chip *chip; | |
372e722e | 1817 | int offset; |
0f6d504e | 1818 | |
bcabdef1 AC |
1819 | if (!desc) |
1820 | return -EINVAL; | |
372e722e AC |
1821 | chip = desc->chip; |
1822 | offset = gpio_chip_hwgpio(desc); | |
1823 | return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO; | |
0f6d504e | 1824 | } |
79a9becd | 1825 | EXPORT_SYMBOL_GPL(gpiod_to_irq); |
0f6d504e | 1826 | |
d468bf9e | 1827 | /** |
e3a2e878 | 1828 | * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ |
d74be6df AC |
1829 | * @chip: the chip the GPIO to lock belongs to |
1830 | * @offset: the offset of the GPIO to lock as IRQ | |
d468bf9e LW |
1831 | * |
1832 | * This is used directly by GPIO drivers that want to lock down | |
f438acdf | 1833 | * a certain GPIO line to be used for IRQs. |
d468bf9e | 1834 | */ |
e3a2e878 | 1835 | int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset) |
372e722e | 1836 | { |
d74be6df | 1837 | if (offset >= chip->ngpio) |
d468bf9e LW |
1838 | return -EINVAL; |
1839 | ||
d74be6df AC |
1840 | if (test_bit(FLAG_IS_OUT, &chip->desc[offset].flags)) { |
1841 | chip_err(chip, | |
d468bf9e LW |
1842 | "%s: tried to flag a GPIO set as output for IRQ\n", |
1843 | __func__); | |
1844 | return -EIO; | |
1845 | } | |
1846 | ||
d74be6df | 1847 | set_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags); |
d468bf9e | 1848 | return 0; |
372e722e | 1849 | } |
e3a2e878 | 1850 | EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq); |
d2876d08 | 1851 | |
d468bf9e | 1852 | /** |
e3a2e878 | 1853 | * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ |
d74be6df AC |
1854 | * @chip: the chip the GPIO to lock belongs to |
1855 | * @offset: the offset of the GPIO to lock as IRQ | |
d468bf9e LW |
1856 | * |
1857 | * This is used directly by GPIO drivers that want to indicate | |
1858 | * that a certain GPIO is no longer used exclusively for IRQ. | |
d2876d08 | 1859 | */ |
e3a2e878 | 1860 | void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) |
d468bf9e | 1861 | { |
d74be6df | 1862 | if (offset >= chip->ngpio) |
d468bf9e | 1863 | return; |
d2876d08 | 1864 | |
d74be6df | 1865 | clear_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags); |
d468bf9e | 1866 | } |
e3a2e878 | 1867 | EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq); |
d468bf9e | 1868 | |
79a9becd AC |
1869 | /** |
1870 | * gpiod_get_raw_value_cansleep() - return a gpio's raw value | |
1871 | * @desc: gpio whose value will be returned | |
1872 | * | |
1873 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding | |
e20538b8 | 1874 | * its ACTIVE_LOW status, or negative errno on failure. |
79a9becd AC |
1875 | * |
1876 | * This function is to be called from contexts that can sleep. | |
d2876d08 | 1877 | */ |
79a9becd | 1878 | int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) |
d2876d08 | 1879 | { |
d2876d08 | 1880 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1881 | if (!desc) |
1882 | return 0; | |
79a9becd | 1883 | return _gpiod_get_raw_value(desc); |
d2876d08 | 1884 | } |
79a9becd | 1885 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); |
372e722e | 1886 | |
79a9becd AC |
1887 | /** |
1888 | * gpiod_get_value_cansleep() - return a gpio's value | |
1889 | * @desc: gpio whose value will be returned | |
1890 | * | |
1891 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into | |
e20538b8 | 1892 | * account, or negative errno on failure. |
79a9becd AC |
1893 | * |
1894 | * This function is to be called from contexts that can sleep. | |
1895 | */ | |
1896 | int gpiod_get_value_cansleep(const struct gpio_desc *desc) | |
d2876d08 | 1897 | { |
3f397c21 | 1898 | int value; |
d2876d08 DB |
1899 | |
1900 | might_sleep_if(extra_checks); | |
bcabdef1 AC |
1901 | if (!desc) |
1902 | return 0; | |
79a9becd AC |
1903 | |
1904 | value = _gpiod_get_raw_value(desc); | |
e20538b8 BA |
1905 | if (value < 0) |
1906 | return value; | |
1907 | ||
79a9becd AC |
1908 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
1909 | value = !value; | |
1910 | ||
3f397c21 | 1911 | return value; |
d2876d08 | 1912 | } |
79a9becd | 1913 | EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); |
372e722e | 1914 | |
79a9becd AC |
1915 | /** |
1916 | * gpiod_set_raw_value_cansleep() - assign a gpio's raw value | |
1917 | * @desc: gpio whose value will be assigned | |
1918 | * @value: value to assign | |
1919 | * | |
1920 | * Set the raw value of the GPIO, i.e. the value of its physical line without | |
1921 | * regard for its ACTIVE_LOW status. | |
1922 | * | |
1923 | * This function is to be called from contexts that can sleep. | |
1924 | */ | |
1925 | void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) | |
372e722e | 1926 | { |
d2876d08 | 1927 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1928 | if (!desc) |
1929 | return; | |
79a9becd | 1930 | _gpiod_set_raw_value(desc, value); |
372e722e | 1931 | } |
79a9becd | 1932 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); |
d2876d08 | 1933 | |
79a9becd AC |
1934 | /** |
1935 | * gpiod_set_value_cansleep() - assign a gpio's value | |
1936 | * @desc: gpio whose value will be assigned | |
1937 | * @value: value to assign | |
1938 | * | |
1939 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into | |
1940 | * account | |
1941 | * | |
1942 | * This function is to be called from contexts that can sleep. | |
1943 | */ | |
1944 | void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) | |
d2876d08 | 1945 | { |
d2876d08 | 1946 | might_sleep_if(extra_checks); |
bcabdef1 AC |
1947 | if (!desc) |
1948 | return; | |
79a9becd AC |
1949 | |
1950 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) | |
1951 | value = !value; | |
1952 | _gpiod_set_raw_value(desc, value); | |
372e722e | 1953 | } |
79a9becd | 1954 | EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); |
d2876d08 | 1955 | |
5f424243 | 1956 | /** |
3fff99bc | 1957 | * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs |
5f424243 RI |
1958 | * @array_size: number of elements in the descriptor / value arrays |
1959 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1960 | * @value_array: array of values to assign | |
1961 | * | |
1962 | * Set the raw values of the GPIOs, i.e. the values of the physical lines | |
1963 | * without regard for their ACTIVE_LOW status. | |
1964 | * | |
1965 | * This function is to be called from contexts that can sleep. | |
1966 | */ | |
3fff99bc RI |
1967 | void gpiod_set_raw_array_value_cansleep(unsigned int array_size, |
1968 | struct gpio_desc **desc_array, | |
1969 | int *value_array) | |
5f424243 RI |
1970 | { |
1971 | might_sleep_if(extra_checks); | |
1972 | if (!desc_array) | |
1973 | return; | |
3fff99bc RI |
1974 | gpiod_set_array_value_priv(true, true, array_size, desc_array, |
1975 | value_array); | |
5f424243 | 1976 | } |
3fff99bc | 1977 | EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep); |
5f424243 RI |
1978 | |
1979 | /** | |
3fff99bc | 1980 | * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs |
5f424243 RI |
1981 | * @array_size: number of elements in the descriptor / value arrays |
1982 | * @desc_array: array of GPIO descriptors whose values will be assigned | |
1983 | * @value_array: array of values to assign | |
1984 | * | |
1985 | * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status | |
1986 | * into account. | |
1987 | * | |
1988 | * This function is to be called from contexts that can sleep. | |
1989 | */ | |
3fff99bc RI |
1990 | void gpiod_set_array_value_cansleep(unsigned int array_size, |
1991 | struct gpio_desc **desc_array, | |
1992 | int *value_array) | |
5f424243 RI |
1993 | { |
1994 | might_sleep_if(extra_checks); | |
1995 | if (!desc_array) | |
1996 | return; | |
3fff99bc RI |
1997 | gpiod_set_array_value_priv(false, true, array_size, desc_array, |
1998 | value_array); | |
5f424243 | 1999 | } |
3fff99bc | 2000 | EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep); |
5f424243 | 2001 | |
bae48da2 | 2002 | /** |
ad824783 AC |
2003 | * gpiod_add_lookup_table() - register GPIO device consumers |
2004 | * @table: table of consumers to register | |
bae48da2 | 2005 | */ |
ad824783 | 2006 | void gpiod_add_lookup_table(struct gpiod_lookup_table *table) |
bae48da2 AC |
2007 | { |
2008 | mutex_lock(&gpio_lookup_lock); | |
2009 | ||
ad824783 | 2010 | list_add_tail(&table->list, &gpio_lookup_list); |
bae48da2 AC |
2011 | |
2012 | mutex_unlock(&gpio_lookup_lock); | |
2013 | } | |
2014 | ||
be9015ab SK |
2015 | /** |
2016 | * gpiod_remove_lookup_table() - unregister GPIO device consumers | |
2017 | * @table: table of consumers to unregister | |
2018 | */ | |
2019 | void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) | |
2020 | { | |
2021 | mutex_lock(&gpio_lookup_lock); | |
2022 | ||
2023 | list_del(&table->list); | |
2024 | ||
2025 | mutex_unlock(&gpio_lookup_lock); | |
2026 | } | |
2027 | ||
bae48da2 | 2028 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, |
53e7cac3 AC |
2029 | unsigned int idx, |
2030 | enum gpio_lookup_flags *flags) | |
bae48da2 AC |
2031 | { |
2032 | char prop_name[32]; /* 32 is max size of property name */ | |
2033 | enum of_gpio_flags of_flags; | |
2034 | struct gpio_desc *desc; | |
dd34c37a | 2035 | unsigned int i; |
bae48da2 | 2036 | |
7f2e553a | 2037 | for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { |
dd34c37a | 2038 | if (con_id) |
9e089246 | 2039 | snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id, |
7f2e553a | 2040 | gpio_suffixes[i]); |
dd34c37a | 2041 | else |
9e089246 | 2042 | snprintf(prop_name, sizeof(prop_name), "%s", |
7f2e553a | 2043 | gpio_suffixes[i]); |
bae48da2 | 2044 | |
dd34c37a TR |
2045 | desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx, |
2046 | &of_flags); | |
06fc3b70 | 2047 | if (!IS_ERR(desc) || (PTR_ERR(desc) == -EPROBE_DEFER)) |
dd34c37a TR |
2048 | break; |
2049 | } | |
bae48da2 AC |
2050 | |
2051 | if (IS_ERR(desc)) | |
2052 | return desc; | |
2053 | ||
2054 | if (of_flags & OF_GPIO_ACTIVE_LOW) | |
53e7cac3 | 2055 | *flags |= GPIO_ACTIVE_LOW; |
bae48da2 | 2056 | |
90b665f6 LP |
2057 | if (of_flags & OF_GPIO_SINGLE_ENDED) { |
2058 | if (of_flags & OF_GPIO_ACTIVE_LOW) | |
2059 | *flags |= GPIO_OPEN_DRAIN; | |
2060 | else | |
2061 | *flags |= GPIO_OPEN_SOURCE; | |
2062 | } | |
2063 | ||
bae48da2 AC |
2064 | return desc; |
2065 | } | |
d2876d08 | 2066 | |
81f59e9d | 2067 | static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id, |
53e7cac3 AC |
2068 | unsigned int idx, |
2069 | enum gpio_lookup_flags *flags) | |
372e722e | 2070 | { |
0d9a693c | 2071 | struct acpi_device *adev = ACPI_COMPANION(dev); |
e01f440a MW |
2072 | struct acpi_gpio_info info; |
2073 | struct gpio_desc *desc; | |
0d9a693c MW |
2074 | char propname[32]; |
2075 | int i; | |
e01f440a | 2076 | |
0d9a693c | 2077 | /* Try first from _DSD */ |
7f2e553a | 2078 | for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { |
0d9a693c MW |
2079 | if (con_id && strcmp(con_id, "gpios")) { |
2080 | snprintf(propname, sizeof(propname), "%s-%s", | |
7f2e553a | 2081 | con_id, gpio_suffixes[i]); |
0d9a693c MW |
2082 | } else { |
2083 | snprintf(propname, sizeof(propname), "%s", | |
7f2e553a | 2084 | gpio_suffixes[i]); |
0d9a693c MW |
2085 | } |
2086 | ||
2087 | desc = acpi_get_gpiod_by_index(adev, propname, idx, &info); | |
2088 | if (!IS_ERR(desc) || (PTR_ERR(desc) == -EPROBE_DEFER)) | |
2089 | break; | |
2090 | } | |
2091 | ||
2092 | /* Then from plain _CRS GPIOs */ | |
2093 | if (IS_ERR(desc)) { | |
10cf4899 DT |
2094 | if (!acpi_can_fallback_to_crs(adev, con_id)) |
2095 | return ERR_PTR(-ENOENT); | |
2096 | ||
0d9a693c MW |
2097 | desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info); |
2098 | if (IS_ERR(desc)) | |
2099 | return desc; | |
2100 | } | |
e01f440a | 2101 | |
52044723 | 2102 | if (info.polarity == GPIO_ACTIVE_LOW) |
53e7cac3 | 2103 | *flags |= GPIO_ACTIVE_LOW; |
e01f440a MW |
2104 | |
2105 | return desc; | |
81f59e9d MW |
2106 | } |
2107 | ||
ad824783 | 2108 | static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) |
bae48da2 AC |
2109 | { |
2110 | const char *dev_id = dev ? dev_name(dev) : NULL; | |
ad824783 | 2111 | struct gpiod_lookup_table *table; |
bae48da2 AC |
2112 | |
2113 | mutex_lock(&gpio_lookup_lock); | |
2114 | ||
ad824783 AC |
2115 | list_for_each_entry(table, &gpio_lookup_list, list) { |
2116 | if (table->dev_id && dev_id) { | |
2117 | /* | |
2118 | * Valid strings on both ends, must be identical to have | |
2119 | * a match | |
2120 | */ | |
2121 | if (!strcmp(table->dev_id, dev_id)) | |
2122 | goto found; | |
2123 | } else { | |
2124 | /* | |
2125 | * One of the pointers is NULL, so both must be to have | |
2126 | * a match | |
2127 | */ | |
2128 | if (dev_id == table->dev_id) | |
2129 | goto found; | |
2130 | } | |
2131 | } | |
2132 | table = NULL; | |
bae48da2 | 2133 | |
ad824783 AC |
2134 | found: |
2135 | mutex_unlock(&gpio_lookup_lock); | |
2136 | return table; | |
2137 | } | |
bae48da2 | 2138 | |
ad824783 AC |
2139 | static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, |
2140 | unsigned int idx, | |
2141 | enum gpio_lookup_flags *flags) | |
2142 | { | |
2a3cf6a3 | 2143 | struct gpio_desc *desc = ERR_PTR(-ENOENT); |
ad824783 AC |
2144 | struct gpiod_lookup_table *table; |
2145 | struct gpiod_lookup *p; | |
bae48da2 | 2146 | |
ad824783 AC |
2147 | table = gpiod_find_lookup_table(dev); |
2148 | if (!table) | |
2149 | return desc; | |
bae48da2 | 2150 | |
ad824783 AC |
2151 | for (p = &table->table[0]; p->chip_label; p++) { |
2152 | struct gpio_chip *chip; | |
bae48da2 | 2153 | |
ad824783 | 2154 | /* idx must always match exactly */ |
bae48da2 AC |
2155 | if (p->idx != idx) |
2156 | continue; | |
2157 | ||
ad824783 AC |
2158 | /* If the lookup entry has a con_id, require exact match */ |
2159 | if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) | |
2160 | continue; | |
bae48da2 | 2161 | |
ad824783 | 2162 | chip = find_chip_by_name(p->chip_label); |
bae48da2 | 2163 | |
ad824783 | 2164 | if (!chip) { |
2a3cf6a3 AC |
2165 | dev_err(dev, "cannot find GPIO chip %s\n", |
2166 | p->chip_label); | |
2167 | return ERR_PTR(-ENODEV); | |
ad824783 | 2168 | } |
bae48da2 | 2169 | |
ad824783 | 2170 | if (chip->ngpio <= p->chip_hwnum) { |
2a3cf6a3 AC |
2171 | dev_err(dev, |
2172 | "requested GPIO %d is out of range [0..%d] for chip %s\n", | |
2173 | idx, chip->ngpio, chip->label); | |
2174 | return ERR_PTR(-EINVAL); | |
bae48da2 | 2175 | } |
bae48da2 | 2176 | |
bb1e88cc | 2177 | desc = gpiochip_get_desc(chip, p->chip_hwnum); |
ad824783 | 2178 | *flags = p->flags; |
bae48da2 | 2179 | |
2a3cf6a3 | 2180 | return desc; |
bae48da2 AC |
2181 | } |
2182 | ||
bae48da2 AC |
2183 | return desc; |
2184 | } | |
2185 | ||
66858527 RI |
2186 | static int dt_gpio_count(struct device *dev, const char *con_id) |
2187 | { | |
2188 | int ret; | |
2189 | char propname[32]; | |
2190 | unsigned int i; | |
2191 | ||
2192 | for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { | |
2193 | if (con_id) | |
2194 | snprintf(propname, sizeof(propname), "%s-%s", | |
2195 | con_id, gpio_suffixes[i]); | |
2196 | else | |
2197 | snprintf(propname, sizeof(propname), "%s", | |
2198 | gpio_suffixes[i]); | |
2199 | ||
2200 | ret = of_gpio_named_count(dev->of_node, propname); | |
2201 | if (ret >= 0) | |
2202 | break; | |
2203 | } | |
2204 | return ret; | |
2205 | } | |
2206 | ||
2207 | static int platform_gpio_count(struct device *dev, const char *con_id) | |
2208 | { | |
2209 | struct gpiod_lookup_table *table; | |
2210 | struct gpiod_lookup *p; | |
2211 | unsigned int count = 0; | |
2212 | ||
2213 | table = gpiod_find_lookup_table(dev); | |
2214 | if (!table) | |
2215 | return -ENOENT; | |
2216 | ||
2217 | for (p = &table->table[0]; p->chip_label; p++) { | |
2218 | if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) || | |
2219 | (!con_id && !p->con_id)) | |
2220 | count++; | |
2221 | } | |
2222 | if (!count) | |
2223 | return -ENOENT; | |
2224 | ||
2225 | return count; | |
2226 | } | |
2227 | ||
2228 | /** | |
2229 | * gpiod_count - return the number of GPIOs associated with a device / function | |
2230 | * or -ENOENT if no GPIO has been assigned to the requested function | |
2231 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
2232 | * @con_id: function within the GPIO consumer | |
2233 | */ | |
2234 | int gpiod_count(struct device *dev, const char *con_id) | |
2235 | { | |
2236 | int count = -ENOENT; | |
2237 | ||
2238 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) | |
2239 | count = dt_gpio_count(dev, con_id); | |
2240 | else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) | |
2241 | count = acpi_gpio_count(dev, con_id); | |
2242 | ||
2243 | if (count < 0) | |
2244 | count = platform_gpio_count(dev, con_id); | |
2245 | ||
2246 | return count; | |
2247 | } | |
2248 | EXPORT_SYMBOL_GPL(gpiod_count); | |
2249 | ||
bae48da2 | 2250 | /** |
0879162f | 2251 | * gpiod_get - obtain a GPIO for a given GPIO function |
ad824783 | 2252 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 | 2253 | * @con_id: function within the GPIO consumer |
39b2bbe3 | 2254 | * @flags: optional GPIO initialization flags |
bae48da2 AC |
2255 | * |
2256 | * Return the GPIO descriptor corresponding to the function con_id of device | |
2a3cf6a3 | 2257 | * dev, -ENOENT if no GPIO has been assigned to the requested function, or |
20a8a968 | 2258 | * another IS_ERR() code if an error occurred while trying to acquire the GPIO. |
bae48da2 | 2259 | */ |
b17d1bf1 | 2260 | struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id, |
39b2bbe3 | 2261 | enum gpiod_flags flags) |
bae48da2 | 2262 | { |
39b2bbe3 | 2263 | return gpiod_get_index(dev, con_id, 0, flags); |
bae48da2 | 2264 | } |
b17d1bf1 | 2265 | EXPORT_SYMBOL_GPL(gpiod_get); |
bae48da2 | 2266 | |
29a1f233 TR |
2267 | /** |
2268 | * gpiod_get_optional - obtain an optional GPIO for a given GPIO function | |
2269 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
2270 | * @con_id: function within the GPIO consumer | |
39b2bbe3 | 2271 | * @flags: optional GPIO initialization flags |
29a1f233 TR |
2272 | * |
2273 | * This is equivalent to gpiod_get(), except that when no GPIO was assigned to | |
2274 | * the requested function it will return NULL. This is convenient for drivers | |
2275 | * that need to handle optional GPIOs. | |
2276 | */ | |
b17d1bf1 | 2277 | struct gpio_desc *__must_check gpiod_get_optional(struct device *dev, |
39b2bbe3 AC |
2278 | const char *con_id, |
2279 | enum gpiod_flags flags) | |
29a1f233 | 2280 | { |
39b2bbe3 | 2281 | return gpiod_get_index_optional(dev, con_id, 0, flags); |
29a1f233 | 2282 | } |
b17d1bf1 | 2283 | EXPORT_SYMBOL_GPL(gpiod_get_optional); |
29a1f233 | 2284 | |
923b93e4 LP |
2285 | /** |
2286 | * gpiod_parse_flags - helper function to parse GPIO lookup flags | |
2287 | * @desc: gpio to be setup | |
2288 | * @lflags: gpio_lookup_flags - returned from of_find_gpio() or | |
2289 | * of_get_gpio_hog() | |
2290 | * | |
2291 | * Set the GPIO descriptor flags based on the given GPIO lookup flags. | |
2292 | */ | |
2293 | static void gpiod_parse_flags(struct gpio_desc *desc, unsigned long lflags) | |
2294 | { | |
2295 | if (lflags & GPIO_ACTIVE_LOW) | |
2296 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
2297 | if (lflags & GPIO_OPEN_DRAIN) | |
2298 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); | |
2299 | if (lflags & GPIO_OPEN_SOURCE) | |
2300 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); | |
2301 | } | |
f625d460 BP |
2302 | |
2303 | /** | |
2304 | * gpiod_configure_flags - helper function to configure a given GPIO | |
2305 | * @desc: gpio whose value will be assigned | |
2306 | * @con_id: function within the GPIO consumer | |
f625d460 BP |
2307 | * @dflags: gpiod_flags - optional GPIO initialization flags |
2308 | * | |
2309 | * Return 0 on success, -ENOENT if no GPIO has been assigned to the | |
2310 | * requested function and/or index, or another IS_ERR() code if an error | |
2311 | * occurred while trying to acquire the GPIO. | |
2312 | */ | |
2313 | static int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, | |
923b93e4 | 2314 | enum gpiod_flags dflags) |
f625d460 BP |
2315 | { |
2316 | int status; | |
2317 | ||
f625d460 BP |
2318 | /* No particular flag request, return here... */ |
2319 | if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) { | |
2320 | pr_debug("no flags found for %s\n", con_id); | |
2321 | return 0; | |
2322 | } | |
2323 | ||
2324 | /* Process flags */ | |
2325 | if (dflags & GPIOD_FLAGS_BIT_DIR_OUT) | |
2326 | status = gpiod_direction_output(desc, | |
2327 | dflags & GPIOD_FLAGS_BIT_DIR_VAL); | |
2328 | else | |
2329 | status = gpiod_direction_input(desc); | |
2330 | ||
2331 | return status; | |
2332 | } | |
2333 | ||
bae48da2 AC |
2334 | /** |
2335 | * gpiod_get_index - obtain a GPIO from a multi-index GPIO function | |
fdd6a5fe | 2336 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
bae48da2 AC |
2337 | * @con_id: function within the GPIO consumer |
2338 | * @idx: index of the GPIO to obtain in the consumer | |
39b2bbe3 | 2339 | * @flags: optional GPIO initialization flags |
bae48da2 AC |
2340 | * |
2341 | * This variant of gpiod_get() allows to access GPIOs other than the first | |
2342 | * defined one for functions that define several GPIOs. | |
2343 | * | |
2a3cf6a3 AC |
2344 | * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the |
2345 | * requested function and/or index, or another IS_ERR() code if an error | |
20a8a968 | 2346 | * occurred while trying to acquire the GPIO. |
bae48da2 | 2347 | */ |
b17d1bf1 | 2348 | struct gpio_desc *__must_check gpiod_get_index(struct device *dev, |
bae48da2 | 2349 | const char *con_id, |
39b2bbe3 AC |
2350 | unsigned int idx, |
2351 | enum gpiod_flags flags) | |
bae48da2 | 2352 | { |
35c5d7fd | 2353 | struct gpio_desc *desc = NULL; |
bae48da2 | 2354 | int status; |
39b2bbe3 | 2355 | enum gpio_lookup_flags lookupflags = 0; |
bae48da2 AC |
2356 | |
2357 | dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); | |
2358 | ||
4d8440b9 RW |
2359 | if (dev) { |
2360 | /* Using device tree? */ | |
2361 | if (IS_ENABLED(CONFIG_OF) && dev->of_node) { | |
2362 | dev_dbg(dev, "using device tree for GPIO lookup\n"); | |
2363 | desc = of_find_gpio(dev, con_id, idx, &lookupflags); | |
2364 | } else if (ACPI_COMPANION(dev)) { | |
2365 | dev_dbg(dev, "using ACPI for GPIO lookup\n"); | |
2366 | desc = acpi_find_gpio(dev, con_id, idx, &lookupflags); | |
2367 | } | |
35c5d7fd AC |
2368 | } |
2369 | ||
2370 | /* | |
2371 | * Either we are not using DT or ACPI, or their lookup did not return | |
2372 | * a result. In that case, use platform lookup as a fallback. | |
2373 | */ | |
2a3cf6a3 | 2374 | if (!desc || desc == ERR_PTR(-ENOENT)) { |
43a8785a | 2375 | dev_dbg(dev, "using lookup tables for GPIO lookup\n"); |
39b2bbe3 | 2376 | desc = gpiod_find(dev, con_id, idx, &lookupflags); |
bae48da2 AC |
2377 | } |
2378 | ||
2379 | if (IS_ERR(desc)) { | |
351cfe0f | 2380 | dev_dbg(dev, "lookup for GPIO %s failed\n", con_id); |
bae48da2 AC |
2381 | return desc; |
2382 | } | |
2383 | ||
923b93e4 LP |
2384 | gpiod_parse_flags(desc, lookupflags); |
2385 | ||
bae48da2 | 2386 | status = gpiod_request(desc, con_id); |
bae48da2 AC |
2387 | if (status < 0) |
2388 | return ERR_PTR(status); | |
2389 | ||
923b93e4 | 2390 | status = gpiod_configure_flags(desc, con_id, flags); |
39b2bbe3 AC |
2391 | if (status < 0) { |
2392 | dev_dbg(dev, "setup of GPIO %s failed\n", con_id); | |
2393 | gpiod_put(desc); | |
2394 | return ERR_PTR(status); | |
2395 | } | |
2396 | ||
bae48da2 AC |
2397 | return desc; |
2398 | } | |
b17d1bf1 | 2399 | EXPORT_SYMBOL_GPL(gpiod_get_index); |
bae48da2 | 2400 | |
40b73183 MW |
2401 | /** |
2402 | * fwnode_get_named_gpiod - obtain a GPIO from firmware node | |
2403 | * @fwnode: handle of the firmware node | |
2404 | * @propname: name of the firmware property representing the GPIO | |
2405 | * | |
2406 | * This function can be used for drivers that get their configuration | |
2407 | * from firmware. | |
2408 | * | |
2409 | * Function properly finds the corresponding GPIO using whatever is the | |
2410 | * underlying firmware interface and then makes sure that the GPIO | |
2411 | * descriptor is requested before it is returned to the caller. | |
2412 | * | |
2413 | * In case of error an ERR_PTR() is returned. | |
2414 | */ | |
2415 | struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, | |
2416 | const char *propname) | |
2417 | { | |
2418 | struct gpio_desc *desc = ERR_PTR(-ENODEV); | |
2419 | bool active_low = false; | |
90b665f6 | 2420 | bool single_ended = false; |
40b73183 MW |
2421 | int ret; |
2422 | ||
2423 | if (!fwnode) | |
2424 | return ERR_PTR(-EINVAL); | |
2425 | ||
2426 | if (is_of_node(fwnode)) { | |
2427 | enum of_gpio_flags flags; | |
2428 | ||
c181fb3e | 2429 | desc = of_get_named_gpiod_flags(to_of_node(fwnode), propname, 0, |
40b73183 | 2430 | &flags); |
90b665f6 | 2431 | if (!IS_ERR(desc)) { |
40b73183 | 2432 | active_low = flags & OF_GPIO_ACTIVE_LOW; |
90b665f6 LP |
2433 | single_ended = flags & OF_GPIO_SINGLE_ENDED; |
2434 | } | |
40b73183 MW |
2435 | } else if (is_acpi_node(fwnode)) { |
2436 | struct acpi_gpio_info info; | |
2437 | ||
504a3374 | 2438 | desc = acpi_node_get_gpiod(fwnode, propname, 0, &info); |
40b73183 | 2439 | if (!IS_ERR(desc)) |
52044723 | 2440 | active_low = info.polarity == GPIO_ACTIVE_LOW; |
40b73183 MW |
2441 | } |
2442 | ||
2443 | if (IS_ERR(desc)) | |
2444 | return desc; | |
2445 | ||
40b73183 MW |
2446 | if (active_low) |
2447 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); | |
2448 | ||
90b665f6 LP |
2449 | if (single_ended) { |
2450 | if (active_low) | |
2451 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); | |
2452 | else | |
2453 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); | |
2454 | } | |
2455 | ||
923b93e4 LP |
2456 | ret = gpiod_request(desc, NULL); |
2457 | if (ret) | |
2458 | return ERR_PTR(ret); | |
2459 | ||
40b73183 MW |
2460 | return desc; |
2461 | } | |
2462 | EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod); | |
2463 | ||
29a1f233 TR |
2464 | /** |
2465 | * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO | |
2466 | * function | |
2467 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
2468 | * @con_id: function within the GPIO consumer | |
2469 | * @index: index of the GPIO to obtain in the consumer | |
39b2bbe3 | 2470 | * @flags: optional GPIO initialization flags |
29a1f233 TR |
2471 | * |
2472 | * This is equivalent to gpiod_get_index(), except that when no GPIO with the | |
2473 | * specified index was assigned to the requested function it will return NULL. | |
2474 | * This is convenient for drivers that need to handle optional GPIOs. | |
2475 | */ | |
b17d1bf1 | 2476 | struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev, |
29a1f233 | 2477 | const char *con_id, |
39b2bbe3 AC |
2478 | unsigned int index, |
2479 | enum gpiod_flags flags) | |
29a1f233 TR |
2480 | { |
2481 | struct gpio_desc *desc; | |
2482 | ||
39b2bbe3 | 2483 | desc = gpiod_get_index(dev, con_id, index, flags); |
29a1f233 TR |
2484 | if (IS_ERR(desc)) { |
2485 | if (PTR_ERR(desc) == -ENOENT) | |
2486 | return NULL; | |
2487 | } | |
2488 | ||
2489 | return desc; | |
2490 | } | |
b17d1bf1 | 2491 | EXPORT_SYMBOL_GPL(gpiod_get_index_optional); |
29a1f233 | 2492 | |
f625d460 BP |
2493 | /** |
2494 | * gpiod_hog - Hog the specified GPIO desc given the provided flags | |
2495 | * @desc: gpio whose value will be assigned | |
2496 | * @name: gpio line name | |
2497 | * @lflags: gpio_lookup_flags - returned from of_find_gpio() or | |
2498 | * of_get_gpio_hog() | |
2499 | * @dflags: gpiod_flags - optional GPIO initialization flags | |
2500 | */ | |
2501 | int gpiod_hog(struct gpio_desc *desc, const char *name, | |
2502 | unsigned long lflags, enum gpiod_flags dflags) | |
2503 | { | |
2504 | struct gpio_chip *chip; | |
2505 | struct gpio_desc *local_desc; | |
2506 | int hwnum; | |
2507 | int status; | |
2508 | ||
2509 | chip = gpiod_to_chip(desc); | |
2510 | hwnum = gpio_chip_hwgpio(desc); | |
2511 | ||
923b93e4 LP |
2512 | gpiod_parse_flags(desc, lflags); |
2513 | ||
f625d460 BP |
2514 | local_desc = gpiochip_request_own_desc(chip, hwnum, name); |
2515 | if (IS_ERR(local_desc)) { | |
a713890d LW |
2516 | pr_err("requesting hog GPIO %s (chip %s, offset %d) failed\n", |
2517 | name, chip->label, hwnum); | |
f625d460 BP |
2518 | return PTR_ERR(local_desc); |
2519 | } | |
2520 | ||
923b93e4 | 2521 | status = gpiod_configure_flags(desc, name, dflags); |
f625d460 | 2522 | if (status < 0) { |
a713890d LW |
2523 | pr_err("setup of hog GPIO %s (chip %s, offset %d) failed\n", |
2524 | name, chip->label, hwnum); | |
f625d460 BP |
2525 | gpiochip_free_own_desc(desc); |
2526 | return status; | |
2527 | } | |
2528 | ||
2529 | /* Mark GPIO as hogged so it can be identified and removed later */ | |
2530 | set_bit(FLAG_IS_HOGGED, &desc->flags); | |
2531 | ||
2532 | pr_info("GPIO line %d (%s) hogged as %s%s\n", | |
2533 | desc_to_gpio(desc), name, | |
2534 | (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input", | |
2535 | (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? | |
2536 | (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":""); | |
2537 | ||
2538 | return 0; | |
2539 | } | |
2540 | ||
2541 | /** | |
2542 | * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog | |
2543 | * @chip: gpio chip to act on | |
2544 | * | |
2545 | * This is only used by of_gpiochip_remove to free hogged gpios | |
2546 | */ | |
2547 | static void gpiochip_free_hogs(struct gpio_chip *chip) | |
2548 | { | |
2549 | int id; | |
2550 | ||
2551 | for (id = 0; id < chip->ngpio; id++) { | |
2552 | if (test_bit(FLAG_IS_HOGGED, &chip->desc[id].flags)) | |
2553 | gpiochip_free_own_desc(&chip->desc[id]); | |
2554 | } | |
2555 | } | |
2556 | ||
66858527 RI |
2557 | /** |
2558 | * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function | |
2559 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
2560 | * @con_id: function within the GPIO consumer | |
2561 | * @flags: optional GPIO initialization flags | |
2562 | * | |
2563 | * This function acquires all the GPIOs defined under a given function. | |
2564 | * | |
2565 | * Return a struct gpio_descs containing an array of descriptors, -ENOENT if | |
2566 | * no GPIO has been assigned to the requested function, or another IS_ERR() | |
2567 | * code if an error occurred while trying to acquire the GPIOs. | |
2568 | */ | |
2569 | struct gpio_descs *__must_check gpiod_get_array(struct device *dev, | |
2570 | const char *con_id, | |
2571 | enum gpiod_flags flags) | |
2572 | { | |
2573 | struct gpio_desc *desc; | |
2574 | struct gpio_descs *descs; | |
2575 | int count; | |
2576 | ||
2577 | count = gpiod_count(dev, con_id); | |
2578 | if (count < 0) | |
2579 | return ERR_PTR(count); | |
2580 | ||
2581 | descs = kzalloc(sizeof(*descs) + sizeof(descs->desc[0]) * count, | |
2582 | GFP_KERNEL); | |
2583 | if (!descs) | |
2584 | return ERR_PTR(-ENOMEM); | |
2585 | ||
2586 | for (descs->ndescs = 0; descs->ndescs < count; ) { | |
2587 | desc = gpiod_get_index(dev, con_id, descs->ndescs, flags); | |
2588 | if (IS_ERR(desc)) { | |
2589 | gpiod_put_array(descs); | |
2590 | return ERR_CAST(desc); | |
2591 | } | |
2592 | descs->desc[descs->ndescs] = desc; | |
2593 | descs->ndescs++; | |
2594 | } | |
2595 | return descs; | |
2596 | } | |
2597 | EXPORT_SYMBOL_GPL(gpiod_get_array); | |
2598 | ||
2599 | /** | |
2600 | * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO | |
2601 | * function | |
2602 | * @dev: GPIO consumer, can be NULL for system-global GPIOs | |
2603 | * @con_id: function within the GPIO consumer | |
2604 | * @flags: optional GPIO initialization flags | |
2605 | * | |
2606 | * This is equivalent to gpiod_get_array(), except that when no GPIO was | |
2607 | * assigned to the requested function it will return NULL. | |
2608 | */ | |
2609 | struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev, | |
2610 | const char *con_id, | |
2611 | enum gpiod_flags flags) | |
2612 | { | |
2613 | struct gpio_descs *descs; | |
2614 | ||
2615 | descs = gpiod_get_array(dev, con_id, flags); | |
2616 | if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT)) | |
2617 | return NULL; | |
2618 | ||
2619 | return descs; | |
2620 | } | |
2621 | EXPORT_SYMBOL_GPL(gpiod_get_array_optional); | |
2622 | ||
bae48da2 AC |
2623 | /** |
2624 | * gpiod_put - dispose of a GPIO descriptor | |
2625 | * @desc: GPIO descriptor to dispose of | |
2626 | * | |
2627 | * No descriptor can be used after gpiod_put() has been called on it. | |
2628 | */ | |
2629 | void gpiod_put(struct gpio_desc *desc) | |
2630 | { | |
2631 | gpiod_free(desc); | |
372e722e | 2632 | } |
bae48da2 | 2633 | EXPORT_SYMBOL_GPL(gpiod_put); |
d2876d08 | 2634 | |
66858527 RI |
2635 | /** |
2636 | * gpiod_put_array - dispose of multiple GPIO descriptors | |
2637 | * @descs: struct gpio_descs containing an array of descriptors | |
2638 | */ | |
2639 | void gpiod_put_array(struct gpio_descs *descs) | |
2640 | { | |
2641 | unsigned int i; | |
2642 | ||
2643 | for (i = 0; i < descs->ndescs; i++) | |
2644 | gpiod_put(descs->desc[i]); | |
2645 | ||
2646 | kfree(descs); | |
2647 | } | |
2648 | EXPORT_SYMBOL_GPL(gpiod_put_array); | |
2649 | ||
3c702e99 LW |
2650 | static int __init gpiolib_dev_init(void) |
2651 | { | |
2652 | int ret; | |
2653 | ||
2654 | /* Register GPIO sysfs bus */ | |
2655 | ret = bus_register(&gpio_bus_type); | |
2656 | if (ret < 0) { | |
2657 | pr_err("gpiolib: could not register GPIO bus type\n"); | |
2658 | return ret; | |
2659 | } | |
2660 | ||
2661 | ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip"); | |
2662 | if (ret < 0) { | |
2663 | pr_err("gpiolib: failed to allocate char dev region\n"); | |
2664 | bus_unregister(&gpio_bus_type); | |
2665 | } | |
2666 | return ret; | |
2667 | } | |
2668 | core_initcall(gpiolib_dev_init); | |
2669 | ||
d2876d08 DB |
2670 | #ifdef CONFIG_DEBUG_FS |
2671 | ||
d2876d08 DB |
2672 | static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip) |
2673 | { | |
2674 | unsigned i; | |
2675 | unsigned gpio = chip->base; | |
6c0b4e6c | 2676 | struct gpio_desc *gdesc = &chip->desc[0]; |
d2876d08 | 2677 | int is_out; |
d468bf9e | 2678 | int is_irq; |
d2876d08 DB |
2679 | |
2680 | for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) { | |
ced433e2 MP |
2681 | if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) { |
2682 | if (gdesc->name) { | |
2683 | seq_printf(s, " gpio-%-3d (%-20.20s)\n", | |
2684 | gpio, gdesc->name); | |
2685 | } | |
d2876d08 | 2686 | continue; |
ced433e2 | 2687 | } |
d2876d08 | 2688 | |
372e722e | 2689 | gpiod_get_direction(gdesc); |
d2876d08 | 2690 | is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); |
d468bf9e | 2691 | is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); |
ced433e2 MP |
2692 | seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s", |
2693 | gpio, gdesc->name ? gdesc->name : "", gdesc->label, | |
d2876d08 DB |
2694 | is_out ? "out" : "in ", |
2695 | chip->get | |
2696 | ? (chip->get(chip, i) ? "hi" : "lo") | |
d468bf9e LW |
2697 | : "? ", |
2698 | is_irq ? "IRQ" : " "); | |
d2876d08 DB |
2699 | seq_printf(s, "\n"); |
2700 | } | |
2701 | } | |
2702 | ||
f9c4a31f | 2703 | static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) |
d2876d08 | 2704 | { |
362432ae | 2705 | unsigned long flags; |
ff2b1359 | 2706 | struct gpio_device *gdev = NULL; |
cb1650d4 | 2707 | loff_t index = *pos; |
d2876d08 | 2708 | |
f9c4a31f | 2709 | s->private = ""; |
d2876d08 | 2710 | |
362432ae | 2711 | spin_lock_irqsave(&gpio_lock, flags); |
ff2b1359 | 2712 | list_for_each_entry(gdev, &gpio_devices, list) |
362432ae GL |
2713 | if (index-- == 0) { |
2714 | spin_unlock_irqrestore(&gpio_lock, flags); | |
ff2b1359 | 2715 | return gdev; |
f9c4a31f | 2716 | } |
362432ae | 2717 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f | 2718 | |
cb1650d4 | 2719 | return NULL; |
f9c4a31f TR |
2720 | } |
2721 | ||
2722 | static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
2723 | { | |
362432ae | 2724 | unsigned long flags; |
ff2b1359 | 2725 | struct gpio_device *gdev = v; |
f9c4a31f TR |
2726 | void *ret = NULL; |
2727 | ||
362432ae | 2728 | spin_lock_irqsave(&gpio_lock, flags); |
ff2b1359 | 2729 | if (list_is_last(&gdev->list, &gpio_devices)) |
cb1650d4 AC |
2730 | ret = NULL; |
2731 | else | |
ff2b1359 | 2732 | ret = list_entry(gdev->list.next, struct gpio_device, list); |
362432ae | 2733 | spin_unlock_irqrestore(&gpio_lock, flags); |
f9c4a31f TR |
2734 | |
2735 | s->private = "\n"; | |
2736 | ++*pos; | |
2737 | ||
2738 | return ret; | |
2739 | } | |
2740 | ||
2741 | static void gpiolib_seq_stop(struct seq_file *s, void *v) | |
2742 | { | |
2743 | } | |
2744 | ||
2745 | static int gpiolib_seq_show(struct seq_file *s, void *v) | |
2746 | { | |
ff2b1359 LW |
2747 | struct gpio_device *gdev = v; |
2748 | struct gpio_chip *chip = gdev->chip; | |
2749 | struct device *parent; | |
2750 | ||
2751 | if (!chip) { | |
2752 | seq_printf(s, "%s%s: (dangling chip)", (char *)s->private, | |
2753 | dev_name(&gdev->dev)); | |
2754 | return 0; | |
2755 | } | |
f9c4a31f | 2756 | |
ff2b1359 LW |
2757 | seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private, |
2758 | dev_name(&gdev->dev), | |
2759 | chip->base, chip->base + chip->ngpio - 1); | |
2760 | parent = chip->parent; | |
2761 | if (parent) | |
2762 | seq_printf(s, ", parent: %s/%s", | |
2763 | parent->bus ? parent->bus->name : "no-bus", | |
2764 | dev_name(parent)); | |
f9c4a31f TR |
2765 | if (chip->label) |
2766 | seq_printf(s, ", %s", chip->label); | |
2767 | if (chip->can_sleep) | |
2768 | seq_printf(s, ", can sleep"); | |
2769 | seq_printf(s, ":\n"); | |
2770 | ||
2771 | if (chip->dbg_show) | |
2772 | chip->dbg_show(s, chip); | |
2773 | else | |
2774 | gpiolib_dbg_show(s, chip); | |
2775 | ||
d2876d08 DB |
2776 | return 0; |
2777 | } | |
2778 | ||
f9c4a31f TR |
2779 | static const struct seq_operations gpiolib_seq_ops = { |
2780 | .start = gpiolib_seq_start, | |
2781 | .next = gpiolib_seq_next, | |
2782 | .stop = gpiolib_seq_stop, | |
2783 | .show = gpiolib_seq_show, | |
2784 | }; | |
2785 | ||
d2876d08 DB |
2786 | static int gpiolib_open(struct inode *inode, struct file *file) |
2787 | { | |
f9c4a31f | 2788 | return seq_open(file, &gpiolib_seq_ops); |
d2876d08 DB |
2789 | } |
2790 | ||
828c0950 | 2791 | static const struct file_operations gpiolib_operations = { |
f9c4a31f | 2792 | .owner = THIS_MODULE, |
d2876d08 DB |
2793 | .open = gpiolib_open, |
2794 | .read = seq_read, | |
2795 | .llseek = seq_lseek, | |
f9c4a31f | 2796 | .release = seq_release, |
d2876d08 DB |
2797 | }; |
2798 | ||
2799 | static int __init gpiolib_debugfs_init(void) | |
2800 | { | |
2801 | /* /sys/kernel/debug/gpio */ | |
2802 | (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO, | |
2803 | NULL, NULL, &gpiolib_operations); | |
2804 | return 0; | |
2805 | } | |
2806 | subsys_initcall(gpiolib_debugfs_init); | |
2807 | ||
2808 | #endif /* DEBUG_FS */ |