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cb8c474e BG |
1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* | |
3 | * GPIO testing driver based on configfs. | |
4 | * | |
5 | * Copyright (C) 2021 Bartosz Golaszewski <brgl@bgdev.pl> | |
6 | */ | |
7 | ||
8 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
9 | ||
10 | #include <linux/bitmap.h> | |
11 | #include <linux/completion.h> | |
12 | #include <linux/configfs.h> | |
13 | #include <linux/device.h> | |
14 | #include <linux/gpio/driver.h> | |
15 | #include <linux/gpio/machine.h> | |
16 | #include <linux/idr.h> | |
17 | #include <linux/interrupt.h> | |
18 | #include <linux/irq.h> | |
19 | #include <linux/irq_sim.h> | |
20 | #include <linux/list.h> | |
21 | #include <linux/mod_devicetable.h> | |
22 | #include <linux/module.h> | |
23 | #include <linux/mutex.h> | |
24 | #include <linux/notifier.h> | |
25 | #include <linux/platform_device.h> | |
26 | #include <linux/property.h> | |
27 | #include <linux/slab.h> | |
28 | #include <linux/string.h> | |
29 | #include <linux/string_helpers.h> | |
30 | #include <linux/sysfs.h> | |
31 | ||
32 | #include "gpiolib.h" | |
33 | ||
11e47bbd | 34 | #define GPIO_SIM_NGPIO_MAX 1024 |
cb8c474e BG |
35 | #define GPIO_SIM_PROP_MAX 4 /* Max 3 properties + sentinel. */ |
36 | #define GPIO_SIM_NUM_ATTRS 3 /* value, pull and sentinel */ | |
37 | ||
38 | static DEFINE_IDA(gpio_sim_ida); | |
39 | ||
40 | struct gpio_sim_chip { | |
41 | struct gpio_chip gc; | |
42 | unsigned long *direction_map; | |
43 | unsigned long *value_map; | |
44 | unsigned long *pull_map; | |
45 | struct irq_domain *irq_sim; | |
46 | struct mutex lock; | |
47 | const struct attribute_group **attr_groups; | |
48 | }; | |
49 | ||
50 | struct gpio_sim_attribute { | |
51 | struct device_attribute dev_attr; | |
52 | unsigned int offset; | |
53 | }; | |
54 | ||
55 | static struct gpio_sim_attribute * | |
56 | to_gpio_sim_attr(struct device_attribute *dev_attr) | |
57 | { | |
58 | return container_of(dev_attr, struct gpio_sim_attribute, dev_attr); | |
59 | } | |
60 | ||
61 | static int gpio_sim_apply_pull(struct gpio_sim_chip *chip, | |
62 | unsigned int offset, int value) | |
63 | { | |
64 | int irq, irq_type, ret; | |
65 | struct gpio_desc *desc; | |
66 | struct gpio_chip *gc; | |
67 | ||
68 | gc = &chip->gc; | |
69 | desc = &gc->gpiodev->descs[offset]; | |
70 | ||
71 | mutex_lock(&chip->lock); | |
72 | ||
73 | if (test_bit(FLAG_REQUESTED, &desc->flags) && | |
74 | !test_bit(FLAG_IS_OUT, &desc->flags)) { | |
75 | if (value == !!test_bit(offset, chip->value_map)) | |
76 | goto set_pull; | |
77 | ||
78 | /* | |
79 | * This is fine - it just means, nobody is listening | |
80 | * for interrupts on this line, otherwise | |
81 | * irq_create_mapping() would have been called from | |
82 | * the to_irq() callback. | |
83 | */ | |
84 | irq = irq_find_mapping(chip->irq_sim, offset); | |
85 | if (!irq) | |
86 | goto set_value; | |
87 | ||
88 | irq_type = irq_get_trigger_type(irq); | |
89 | ||
90 | if ((value && (irq_type & IRQ_TYPE_EDGE_RISING)) || | |
91 | (!value && (irq_type & IRQ_TYPE_EDGE_FALLING))) { | |
92 | ret = irq_set_irqchip_state(irq, IRQCHIP_STATE_PENDING, | |
93 | true); | |
94 | if (ret) | |
95 | goto set_pull; | |
96 | } | |
97 | } | |
98 | ||
99 | set_value: | |
100 | /* Change the value unless we're actively driving the line. */ | |
101 | if (!test_bit(FLAG_REQUESTED, &desc->flags) || | |
102 | !test_bit(FLAG_IS_OUT, &desc->flags)) | |
103 | __assign_bit(offset, chip->value_map, value); | |
104 | ||
105 | set_pull: | |
106 | __assign_bit(offset, chip->pull_map, value); | |
107 | mutex_unlock(&chip->lock); | |
108 | return 0; | |
109 | } | |
110 | ||
111 | static int gpio_sim_get(struct gpio_chip *gc, unsigned int offset) | |
112 | { | |
113 | struct gpio_sim_chip *chip = gpiochip_get_data(gc); | |
114 | int ret; | |
115 | ||
116 | mutex_lock(&chip->lock); | |
117 | ret = !!test_bit(offset, chip->value_map); | |
118 | mutex_unlock(&chip->lock); | |
119 | ||
120 | return ret; | |
121 | } | |
122 | ||
123 | static void gpio_sim_set(struct gpio_chip *gc, unsigned int offset, int value) | |
124 | { | |
125 | struct gpio_sim_chip *chip = gpiochip_get_data(gc); | |
126 | ||
127 | mutex_lock(&chip->lock); | |
128 | __assign_bit(offset, chip->value_map, value); | |
129 | mutex_unlock(&chip->lock); | |
130 | } | |
131 | ||
132 | static int gpio_sim_get_multiple(struct gpio_chip *gc, | |
133 | unsigned long *mask, unsigned long *bits) | |
134 | { | |
135 | struct gpio_sim_chip *chip = gpiochip_get_data(gc); | |
136 | ||
137 | mutex_lock(&chip->lock); | |
3836c73e | 138 | bitmap_replace(bits, bits, chip->value_map, mask, gc->ngpio); |
cb8c474e BG |
139 | mutex_unlock(&chip->lock); |
140 | ||
141 | return 0; | |
142 | } | |
143 | ||
144 | static void gpio_sim_set_multiple(struct gpio_chip *gc, | |
145 | unsigned long *mask, unsigned long *bits) | |
146 | { | |
147 | struct gpio_sim_chip *chip = gpiochip_get_data(gc); | |
148 | ||
149 | mutex_lock(&chip->lock); | |
3836c73e | 150 | bitmap_replace(chip->value_map, chip->value_map, bits, mask, gc->ngpio); |
cb8c474e BG |
151 | mutex_unlock(&chip->lock); |
152 | } | |
153 | ||
154 | static int gpio_sim_direction_output(struct gpio_chip *gc, | |
155 | unsigned int offset, int value) | |
156 | { | |
157 | struct gpio_sim_chip *chip = gpiochip_get_data(gc); | |
158 | ||
159 | mutex_lock(&chip->lock); | |
160 | __clear_bit(offset, chip->direction_map); | |
161 | __assign_bit(offset, chip->value_map, value); | |
162 | mutex_unlock(&chip->lock); | |
163 | ||
164 | return 0; | |
165 | } | |
166 | ||
167 | static int gpio_sim_direction_input(struct gpio_chip *gc, unsigned int offset) | |
168 | { | |
169 | struct gpio_sim_chip *chip = gpiochip_get_data(gc); | |
170 | ||
171 | mutex_lock(&chip->lock); | |
172 | __set_bit(offset, chip->direction_map); | |
173 | mutex_unlock(&chip->lock); | |
174 | ||
175 | return 0; | |
176 | } | |
177 | ||
178 | static int gpio_sim_get_direction(struct gpio_chip *gc, unsigned int offset) | |
179 | { | |
180 | struct gpio_sim_chip *chip = gpiochip_get_data(gc); | |
181 | int direction; | |
182 | ||
183 | mutex_lock(&chip->lock); | |
184 | direction = !!test_bit(offset, chip->direction_map); | |
185 | mutex_unlock(&chip->lock); | |
186 | ||
187 | return direction ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT; | |
188 | } | |
189 | ||
190 | static int gpio_sim_set_config(struct gpio_chip *gc, | |
191 | unsigned int offset, unsigned long config) | |
192 | { | |
193 | struct gpio_sim_chip *chip = gpiochip_get_data(gc); | |
194 | ||
195 | switch (pinconf_to_config_param(config)) { | |
196 | case PIN_CONFIG_BIAS_PULL_UP: | |
197 | return gpio_sim_apply_pull(chip, offset, 1); | |
198 | case PIN_CONFIG_BIAS_PULL_DOWN: | |
199 | return gpio_sim_apply_pull(chip, offset, 0); | |
200 | default: | |
201 | break; | |
202 | } | |
203 | ||
204 | return -ENOTSUPP; | |
205 | } | |
206 | ||
207 | static int gpio_sim_to_irq(struct gpio_chip *gc, unsigned int offset) | |
208 | { | |
209 | struct gpio_sim_chip *chip = gpiochip_get_data(gc); | |
210 | ||
211 | return irq_create_mapping(chip->irq_sim, offset); | |
212 | } | |
213 | ||
214 | static void gpio_sim_free(struct gpio_chip *gc, unsigned int offset) | |
215 | { | |
216 | struct gpio_sim_chip *chip = gpiochip_get_data(gc); | |
217 | ||
218 | mutex_lock(&chip->lock); | |
219 | __assign_bit(offset, chip->value_map, !!test_bit(offset, chip->pull_map)); | |
220 | mutex_unlock(&chip->lock); | |
221 | } | |
222 | ||
223 | static ssize_t gpio_sim_sysfs_val_show(struct device *dev, | |
224 | struct device_attribute *attr, char *buf) | |
225 | { | |
226 | struct gpio_sim_attribute *line_attr = to_gpio_sim_attr(attr); | |
227 | struct gpio_sim_chip *chip = dev_get_drvdata(dev); | |
228 | int val; | |
229 | ||
230 | mutex_lock(&chip->lock); | |
231 | val = !!test_bit(line_attr->offset, chip->value_map); | |
232 | mutex_unlock(&chip->lock); | |
233 | ||
234 | return sysfs_emit(buf, "%d\n", val); | |
235 | } | |
236 | ||
237 | static ssize_t gpio_sim_sysfs_val_store(struct device *dev, | |
238 | struct device_attribute *attr, | |
239 | const char *buf, size_t count) | |
240 | { | |
241 | /* | |
242 | * Not assigning this function will result in write() returning -EIO | |
243 | * which is confusing. Return -EPERM explicitly. | |
244 | */ | |
245 | return -EPERM; | |
246 | } | |
247 | ||
248 | static const char *const gpio_sim_sysfs_pull_strings[] = { | |
249 | [0] = "pull-down", | |
250 | [1] = "pull-up", | |
251 | }; | |
252 | ||
253 | static ssize_t gpio_sim_sysfs_pull_show(struct device *dev, | |
254 | struct device_attribute *attr, | |
255 | char *buf) | |
256 | { | |
257 | struct gpio_sim_attribute *line_attr = to_gpio_sim_attr(attr); | |
258 | struct gpio_sim_chip *chip = dev_get_drvdata(dev); | |
259 | int pull; | |
260 | ||
261 | mutex_lock(&chip->lock); | |
262 | pull = !!test_bit(line_attr->offset, chip->pull_map); | |
263 | mutex_unlock(&chip->lock); | |
264 | ||
265 | return sysfs_emit(buf, "%s\n", gpio_sim_sysfs_pull_strings[pull]); | |
266 | } | |
267 | ||
268 | static ssize_t gpio_sim_sysfs_pull_store(struct device *dev, | |
269 | struct device_attribute *attr, | |
270 | const char *buf, size_t len) | |
271 | { | |
272 | struct gpio_sim_attribute *line_attr = to_gpio_sim_attr(attr); | |
273 | struct gpio_sim_chip *chip = dev_get_drvdata(dev); | |
274 | int ret, pull; | |
275 | ||
276 | pull = sysfs_match_string(gpio_sim_sysfs_pull_strings, buf); | |
277 | if (pull < 0) | |
278 | return pull; | |
279 | ||
280 | ret = gpio_sim_apply_pull(chip, line_attr->offset, pull); | |
281 | if (ret) | |
282 | return ret; | |
283 | ||
284 | return len; | |
285 | } | |
286 | ||
287 | static void gpio_sim_mutex_destroy(void *data) | |
288 | { | |
289 | struct mutex *lock = data; | |
290 | ||
291 | mutex_destroy(lock); | |
292 | } | |
293 | ||
294 | static void gpio_sim_sysfs_remove(void *data) | |
295 | { | |
296 | struct gpio_sim_chip *chip = data; | |
297 | ||
298 | sysfs_remove_groups(&chip->gc.gpiodev->dev.kobj, chip->attr_groups); | |
299 | } | |
300 | ||
301 | static int gpio_sim_setup_sysfs(struct gpio_sim_chip *chip) | |
302 | { | |
303 | struct device_attribute *val_dev_attr, *pull_dev_attr; | |
304 | struct gpio_sim_attribute *val_attr, *pull_attr; | |
305 | unsigned int num_lines = chip->gc.ngpio; | |
306 | struct device *dev = chip->gc.parent; | |
307 | struct attribute_group *attr_group; | |
308 | struct attribute **attrs; | |
309 | int i, ret; | |
310 | ||
311 | chip->attr_groups = devm_kcalloc(dev, sizeof(*chip->attr_groups), | |
312 | num_lines + 1, GFP_KERNEL); | |
313 | if (!chip->attr_groups) | |
314 | return -ENOMEM; | |
315 | ||
316 | for (i = 0; i < num_lines; i++) { | |
317 | attr_group = devm_kzalloc(dev, sizeof(*attr_group), GFP_KERNEL); | |
c680c6a8 CJ |
318 | attrs = devm_kcalloc(dev, GPIO_SIM_NUM_ATTRS, sizeof(*attrs), |
319 | GFP_KERNEL); | |
cb8c474e BG |
320 | val_attr = devm_kzalloc(dev, sizeof(*val_attr), GFP_KERNEL); |
321 | pull_attr = devm_kzalloc(dev, sizeof(*pull_attr), GFP_KERNEL); | |
322 | if (!attr_group || !attrs || !val_attr || !pull_attr) | |
323 | return -ENOMEM; | |
324 | ||
325 | attr_group->name = devm_kasprintf(dev, GFP_KERNEL, | |
326 | "sim_gpio%u", i); | |
327 | if (!attr_group->name) | |
328 | return -ENOMEM; | |
329 | ||
330 | val_attr->offset = pull_attr->offset = i; | |
331 | ||
332 | val_dev_attr = &val_attr->dev_attr; | |
333 | pull_dev_attr = &pull_attr->dev_attr; | |
334 | ||
335 | sysfs_attr_init(&val_dev_attr->attr); | |
336 | sysfs_attr_init(&pull_dev_attr->attr); | |
337 | ||
338 | val_dev_attr->attr.name = "value"; | |
339 | pull_dev_attr->attr.name = "pull"; | |
340 | ||
341 | val_dev_attr->attr.mode = pull_dev_attr->attr.mode = 0644; | |
342 | ||
343 | val_dev_attr->show = gpio_sim_sysfs_val_show; | |
344 | val_dev_attr->store = gpio_sim_sysfs_val_store; | |
345 | pull_dev_attr->show = gpio_sim_sysfs_pull_show; | |
346 | pull_dev_attr->store = gpio_sim_sysfs_pull_store; | |
347 | ||
348 | attrs[0] = &val_dev_attr->attr; | |
349 | attrs[1] = &pull_dev_attr->attr; | |
350 | ||
351 | attr_group->attrs = attrs; | |
352 | chip->attr_groups[i] = attr_group; | |
353 | } | |
354 | ||
355 | ret = sysfs_create_groups(&chip->gc.gpiodev->dev.kobj, | |
356 | chip->attr_groups); | |
357 | if (ret) | |
358 | return ret; | |
359 | ||
360 | return devm_add_action_or_reset(dev, gpio_sim_sysfs_remove, chip); | |
361 | } | |
362 | ||
363 | static int gpio_sim_add_bank(struct fwnode_handle *swnode, struct device *dev) | |
364 | { | |
365 | struct gpio_sim_chip *chip; | |
366 | struct gpio_chip *gc; | |
367 | const char *label; | |
368 | u32 num_lines; | |
369 | int ret; | |
370 | ||
371 | ret = fwnode_property_read_u32(swnode, "ngpios", &num_lines); | |
372 | if (ret) | |
373 | return ret; | |
374 | ||
11e47bbd BG |
375 | if (num_lines > GPIO_SIM_NGPIO_MAX) |
376 | return -ERANGE; | |
377 | ||
cb8c474e BG |
378 | ret = fwnode_property_read_string(swnode, "gpio-sim,label", &label); |
379 | if (ret) { | |
4827aae0 AS |
380 | label = devm_kasprintf(dev, GFP_KERNEL, "%s-%pfwP", |
381 | dev_name(dev), swnode); | |
cb8c474e BG |
382 | if (!label) |
383 | return -ENOMEM; | |
384 | } | |
385 | ||
386 | chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL); | |
387 | if (!chip) | |
388 | return -ENOMEM; | |
389 | ||
390 | chip->direction_map = devm_bitmap_alloc(dev, num_lines, GFP_KERNEL); | |
391 | if (!chip->direction_map) | |
392 | return -ENOMEM; | |
393 | ||
394 | /* Default to input mode. */ | |
395 | bitmap_fill(chip->direction_map, num_lines); | |
396 | ||
397 | chip->value_map = devm_bitmap_zalloc(dev, num_lines, GFP_KERNEL); | |
398 | if (!chip->value_map) | |
399 | return -ENOMEM; | |
400 | ||
401 | chip->pull_map = devm_bitmap_zalloc(dev, num_lines, GFP_KERNEL); | |
402 | if (!chip->pull_map) | |
403 | return -ENOMEM; | |
404 | ||
405 | chip->irq_sim = devm_irq_domain_create_sim(dev, NULL, num_lines); | |
406 | if (IS_ERR(chip->irq_sim)) | |
407 | return PTR_ERR(chip->irq_sim); | |
408 | ||
409 | mutex_init(&chip->lock); | |
410 | ret = devm_add_action_or_reset(dev, gpio_sim_mutex_destroy, | |
411 | &chip->lock); | |
412 | if (ret) | |
413 | return ret; | |
414 | ||
415 | gc = &chip->gc; | |
416 | gc->base = -1; | |
417 | gc->ngpio = num_lines; | |
418 | gc->label = label; | |
419 | gc->owner = THIS_MODULE; | |
420 | gc->parent = dev; | |
421 | gc->fwnode = swnode; | |
422 | gc->get = gpio_sim_get; | |
423 | gc->set = gpio_sim_set; | |
424 | gc->get_multiple = gpio_sim_get_multiple; | |
425 | gc->set_multiple = gpio_sim_set_multiple; | |
426 | gc->direction_output = gpio_sim_direction_output; | |
427 | gc->direction_input = gpio_sim_direction_input; | |
428 | gc->get_direction = gpio_sim_get_direction; | |
429 | gc->set_config = gpio_sim_set_config; | |
430 | gc->to_irq = gpio_sim_to_irq; | |
431 | gc->free = gpio_sim_free; | |
432 | ||
433 | ret = devm_gpiochip_add_data(dev, gc, chip); | |
434 | if (ret) | |
435 | return ret; | |
436 | ||
437 | /* Used by sysfs and configfs callbacks. */ | |
438 | dev_set_drvdata(&gc->gpiodev->dev, chip); | |
439 | ||
440 | return gpio_sim_setup_sysfs(chip); | |
441 | } | |
442 | ||
443 | static int gpio_sim_probe(struct platform_device *pdev) | |
444 | { | |
445 | struct device *dev = &pdev->dev; | |
446 | struct fwnode_handle *swnode; | |
447 | int ret; | |
448 | ||
449 | device_for_each_child_node(dev, swnode) { | |
450 | ret = gpio_sim_add_bank(swnode, dev); | |
a2d05fb7 YY |
451 | if (ret) { |
452 | fwnode_handle_put(swnode); | |
cb8c474e | 453 | return ret; |
a2d05fb7 | 454 | } |
cb8c474e BG |
455 | } |
456 | ||
457 | return 0; | |
458 | } | |
459 | ||
460 | static const struct of_device_id gpio_sim_of_match[] = { | |
461 | { .compatible = "gpio-simulator" }, | |
462 | { } | |
463 | }; | |
464 | MODULE_DEVICE_TABLE(of, gpio_sim_of_match); | |
465 | ||
466 | static struct platform_driver gpio_sim_driver = { | |
467 | .driver = { | |
468 | .name = "gpio-sim", | |
469 | .of_match_table = gpio_sim_of_match, | |
470 | }, | |
471 | .probe = gpio_sim_probe, | |
472 | }; | |
473 | ||
474 | struct gpio_sim_device { | |
475 | struct config_group group; | |
476 | ||
477 | /* | |
478 | * If pdev is NULL, the device is 'pending' (waiting for configuration). | |
479 | * Once the pointer is assigned, the device has been created and the | |
480 | * item is 'live'. | |
481 | */ | |
482 | struct platform_device *pdev; | |
483 | int id; | |
484 | ||
485 | /* | |
486 | * Each configfs filesystem operation is protected with the subsystem | |
487 | * mutex. Each separate attribute is protected with the buffer mutex. | |
488 | * This structure however can be modified by callbacks of different | |
489 | * attributes so we need another lock. | |
490 | * | |
491 | * We use this lock fo protecting all data structures owned by this | |
492 | * object too. | |
493 | */ | |
494 | struct mutex lock; | |
495 | ||
496 | /* | |
497 | * This is used to synchronously wait for the driver's probe to complete | |
498 | * and notify the user-space about any errors. | |
499 | */ | |
500 | struct notifier_block bus_notifier; | |
501 | struct completion probe_completion; | |
502 | bool driver_bound; | |
503 | ||
504 | struct gpiod_hog *hogs; | |
505 | ||
506 | struct list_head bank_list; | |
507 | }; | |
508 | ||
509 | /* This is called with dev->lock already taken. */ | |
510 | static int gpio_sim_bus_notifier_call(struct notifier_block *nb, | |
511 | unsigned long action, void *data) | |
512 | { | |
513 | struct gpio_sim_device *simdev = container_of(nb, | |
514 | struct gpio_sim_device, | |
515 | bus_notifier); | |
516 | struct device *dev = data; | |
517 | char devname[32]; | |
518 | ||
519 | snprintf(devname, sizeof(devname), "gpio-sim.%u", simdev->id); | |
520 | ||
521 | if (strcmp(dev_name(dev), devname) == 0) { | |
522 | if (action == BUS_NOTIFY_BOUND_DRIVER) | |
523 | simdev->driver_bound = true; | |
524 | else if (action == BUS_NOTIFY_DRIVER_NOT_BOUND) | |
525 | simdev->driver_bound = false; | |
526 | else | |
527 | return NOTIFY_DONE; | |
528 | ||
529 | complete(&simdev->probe_completion); | |
530 | return NOTIFY_OK; | |
531 | } | |
532 | ||
533 | return NOTIFY_DONE; | |
534 | } | |
535 | ||
536 | static struct gpio_sim_device *to_gpio_sim_device(struct config_item *item) | |
537 | { | |
538 | struct config_group *group = to_config_group(item); | |
539 | ||
540 | return container_of(group, struct gpio_sim_device, group); | |
541 | } | |
542 | ||
543 | struct gpio_sim_bank { | |
544 | struct config_group group; | |
545 | ||
546 | /* | |
547 | * We could have used the ci_parent field of the config_item but | |
548 | * configfs is stupid and calls the item's release callback after | |
549 | * already having cleared the parent pointer even though the parent | |
550 | * is guaranteed to survive the child... | |
551 | * | |
552 | * So we need to store the pointer to the parent struct here. We can | |
553 | * dereference it anywhere we need with no checks and no locking as | |
55d01c98 | 554 | * it's guaranteed to survive the children and protected by configfs |
cb8c474e BG |
555 | * locks. |
556 | * | |
557 | * Same for other structures. | |
558 | */ | |
559 | struct gpio_sim_device *parent; | |
560 | struct list_head siblings; | |
561 | ||
562 | char *label; | |
563 | unsigned int num_lines; | |
564 | ||
565 | struct list_head line_list; | |
566 | ||
567 | struct fwnode_handle *swnode; | |
568 | }; | |
569 | ||
570 | static struct gpio_sim_bank *to_gpio_sim_bank(struct config_item *item) | |
571 | { | |
572 | struct config_group *group = to_config_group(item); | |
573 | ||
574 | return container_of(group, struct gpio_sim_bank, group); | |
575 | } | |
576 | ||
c162ca0b BG |
577 | static bool gpio_sim_bank_has_label(struct gpio_sim_bank *bank) |
578 | { | |
579 | return bank->label && *bank->label; | |
580 | } | |
581 | ||
cb8c474e BG |
582 | static struct gpio_sim_device * |
583 | gpio_sim_bank_get_device(struct gpio_sim_bank *bank) | |
584 | { | |
585 | return bank->parent; | |
586 | } | |
587 | ||
588 | struct gpio_sim_hog; | |
589 | ||
590 | struct gpio_sim_line { | |
591 | struct config_group group; | |
592 | ||
593 | struct gpio_sim_bank *parent; | |
594 | struct list_head siblings; | |
595 | ||
596 | unsigned int offset; | |
597 | char *name; | |
598 | ||
599 | /* There can only be one hog per line. */ | |
600 | struct gpio_sim_hog *hog; | |
601 | }; | |
602 | ||
603 | static struct gpio_sim_line *to_gpio_sim_line(struct config_item *item) | |
604 | { | |
605 | struct config_group *group = to_config_group(item); | |
606 | ||
607 | return container_of(group, struct gpio_sim_line, group); | |
608 | } | |
609 | ||
610 | static struct gpio_sim_device * | |
611 | gpio_sim_line_get_device(struct gpio_sim_line *line) | |
612 | { | |
613 | struct gpio_sim_bank *bank = line->parent; | |
614 | ||
615 | return gpio_sim_bank_get_device(bank); | |
616 | } | |
617 | ||
618 | struct gpio_sim_hog { | |
619 | struct config_item item; | |
620 | struct gpio_sim_line *parent; | |
621 | ||
622 | char *name; | |
623 | int dir; | |
624 | }; | |
625 | ||
626 | static struct gpio_sim_hog *to_gpio_sim_hog(struct config_item *item) | |
627 | { | |
628 | return container_of(item, struct gpio_sim_hog, item); | |
629 | } | |
630 | ||
631 | static struct gpio_sim_device *gpio_sim_hog_get_device(struct gpio_sim_hog *hog) | |
632 | { | |
633 | struct gpio_sim_line *line = hog->parent; | |
634 | ||
635 | return gpio_sim_line_get_device(line); | |
636 | } | |
637 | ||
638 | static bool gpio_sim_device_is_live_unlocked(struct gpio_sim_device *dev) | |
639 | { | |
640 | return !!dev->pdev; | |
641 | } | |
642 | ||
643 | static char *gpio_sim_strdup_trimmed(const char *str, size_t count) | |
644 | { | |
645 | char *dup, *trimmed; | |
646 | ||
647 | dup = kstrndup(str, count, GFP_KERNEL); | |
648 | if (!dup) | |
649 | return NULL; | |
650 | ||
651 | trimmed = strstrip(dup); | |
652 | memmove(dup, trimmed, strlen(trimmed) + 1); | |
653 | ||
654 | return dup; | |
655 | } | |
656 | ||
657 | static ssize_t gpio_sim_device_config_dev_name_show(struct config_item *item, | |
658 | char *page) | |
659 | { | |
660 | struct gpio_sim_device *dev = to_gpio_sim_device(item); | |
661 | struct platform_device *pdev; | |
662 | int ret; | |
663 | ||
664 | mutex_lock(&dev->lock); | |
665 | pdev = dev->pdev; | |
666 | if (pdev) | |
667 | ret = sprintf(page, "%s\n", dev_name(&pdev->dev)); | |
668 | else | |
669 | ret = sprintf(page, "gpio-sim.%d\n", dev->id); | |
670 | mutex_unlock(&dev->lock); | |
671 | ||
672 | return ret; | |
673 | } | |
674 | ||
675 | CONFIGFS_ATTR_RO(gpio_sim_device_config_, dev_name); | |
676 | ||
677 | static ssize_t | |
678 | gpio_sim_device_config_live_show(struct config_item *item, char *page) | |
679 | { | |
680 | struct gpio_sim_device *dev = to_gpio_sim_device(item); | |
681 | bool live; | |
682 | ||
683 | mutex_lock(&dev->lock); | |
684 | live = gpio_sim_device_is_live_unlocked(dev); | |
685 | mutex_unlock(&dev->lock); | |
686 | ||
687 | return sprintf(page, "%c\n", live ? '1' : '0'); | |
688 | } | |
689 | ||
690 | static char **gpio_sim_make_line_names(struct gpio_sim_bank *bank, | |
691 | unsigned int *line_names_size) | |
692 | { | |
693 | unsigned int max_offset = 0; | |
694 | bool has_line_names = false; | |
695 | struct gpio_sim_line *line; | |
696 | char **line_names; | |
697 | ||
698 | list_for_each_entry(line, &bank->line_list, siblings) { | |
699 | if (line->name) { | |
700 | if (line->offset > max_offset) | |
701 | max_offset = line->offset; | |
702 | ||
703 | /* | |
704 | * max_offset can stay at 0 so it's not an indicator | |
705 | * of whether line names were configured at all. | |
706 | */ | |
707 | has_line_names = true; | |
708 | } | |
709 | } | |
710 | ||
711 | if (!has_line_names) | |
712 | /* | |
713 | * This is not an error - NULL means, there are no line | |
714 | * names configured. | |
715 | */ | |
716 | return NULL; | |
717 | ||
718 | *line_names_size = max_offset + 1; | |
719 | ||
720 | line_names = kcalloc(*line_names_size, sizeof(*line_names), GFP_KERNEL); | |
721 | if (!line_names) | |
722 | return ERR_PTR(-ENOMEM); | |
723 | ||
724 | list_for_each_entry(line, &bank->line_list, siblings) | |
725 | line_names[line->offset] = line->name; | |
726 | ||
727 | return line_names; | |
728 | } | |
729 | ||
730 | static void gpio_sim_remove_hogs(struct gpio_sim_device *dev) | |
731 | { | |
732 | struct gpiod_hog *hog; | |
733 | ||
734 | if (!dev->hogs) | |
735 | return; | |
736 | ||
737 | gpiod_remove_hogs(dev->hogs); | |
738 | ||
79eeab1d | 739 | for (hog = dev->hogs; hog->chip_label; hog++) { |
cb8c474e BG |
740 | kfree(hog->chip_label); |
741 | kfree(hog->line_name); | |
742 | } | |
743 | ||
744 | kfree(dev->hogs); | |
745 | dev->hogs = NULL; | |
746 | } | |
747 | ||
748 | static int gpio_sim_add_hogs(struct gpio_sim_device *dev) | |
749 | { | |
750 | unsigned int num_hogs = 0, idx = 0; | |
751 | struct gpio_sim_bank *bank; | |
752 | struct gpio_sim_line *line; | |
753 | struct gpiod_hog *hog; | |
754 | ||
755 | list_for_each_entry(bank, &dev->bank_list, siblings) { | |
756 | list_for_each_entry(line, &bank->line_list, siblings) { | |
757 | if (line->hog) | |
758 | num_hogs++; | |
759 | } | |
760 | } | |
761 | ||
762 | if (!num_hogs) | |
763 | return 0; | |
764 | ||
765 | /* Allocate one more for the sentinel. */ | |
766 | dev->hogs = kcalloc(num_hogs + 1, sizeof(*dev->hogs), GFP_KERNEL); | |
767 | if (!dev->hogs) | |
768 | return -ENOMEM; | |
769 | ||
770 | list_for_each_entry(bank, &dev->bank_list, siblings) { | |
771 | list_for_each_entry(line, &bank->line_list, siblings) { | |
772 | if (!line->hog) | |
773 | continue; | |
774 | ||
775 | hog = &dev->hogs[idx++]; | |
776 | ||
777 | /* | |
778 | * We need to make this string manually because at this | |
779 | * point the device doesn't exist yet and so dev_name() | |
780 | * is not available. | |
781 | */ | |
c162ca0b BG |
782 | if (gpio_sim_bank_has_label(bank)) |
783 | hog->chip_label = kstrdup(bank->label, | |
784 | GFP_KERNEL); | |
785 | else | |
786 | hog->chip_label = kasprintf(GFP_KERNEL, | |
4827aae0 | 787 | "gpio-sim.%u-%pfwP", |
c162ca0b | 788 | dev->id, |
4827aae0 | 789 | bank->swnode); |
cb8c474e BG |
790 | if (!hog->chip_label) { |
791 | gpio_sim_remove_hogs(dev); | |
792 | return -ENOMEM; | |
793 | } | |
794 | ||
795 | /* | |
796 | * We need to duplicate this because the hog config | |
797 | * item can be removed at any time (and we can't block | |
798 | * it) and gpiolib doesn't make a deep copy of the hog | |
799 | * data. | |
800 | */ | |
801 | if (line->hog->name) { | |
802 | hog->line_name = kstrdup(line->hog->name, | |
803 | GFP_KERNEL); | |
804 | if (!hog->line_name) { | |
805 | gpio_sim_remove_hogs(dev); | |
806 | return -ENOMEM; | |
807 | } | |
808 | } | |
809 | ||
810 | hog->chip_hwnum = line->offset; | |
811 | hog->dflags = line->hog->dir; | |
812 | } | |
813 | } | |
814 | ||
815 | gpiod_add_hogs(dev->hogs); | |
816 | ||
817 | return 0; | |
818 | } | |
819 | ||
820 | static struct fwnode_handle * | |
821 | gpio_sim_make_bank_swnode(struct gpio_sim_bank *bank, | |
822 | struct fwnode_handle *parent) | |
823 | { | |
824 | struct property_entry properties[GPIO_SIM_PROP_MAX]; | |
825 | unsigned int prop_idx = 0, line_names_size = 0; | |
826 | struct fwnode_handle *swnode; | |
827 | char **line_names; | |
828 | ||
829 | memset(properties, 0, sizeof(properties)); | |
830 | ||
831 | properties[prop_idx++] = PROPERTY_ENTRY_U32("ngpios", bank->num_lines); | |
832 | ||
c162ca0b | 833 | if (gpio_sim_bank_has_label(bank)) |
cb8c474e BG |
834 | properties[prop_idx++] = PROPERTY_ENTRY_STRING("gpio-sim,label", |
835 | bank->label); | |
836 | ||
837 | line_names = gpio_sim_make_line_names(bank, &line_names_size); | |
838 | if (IS_ERR(line_names)) | |
839 | return ERR_CAST(line_names); | |
840 | ||
841 | if (line_names) | |
842 | properties[prop_idx++] = PROPERTY_ENTRY_STRING_ARRAY_LEN( | |
843 | "gpio-line-names", | |
844 | line_names, line_names_size); | |
845 | ||
846 | swnode = fwnode_create_software_node(properties, parent); | |
847 | kfree(line_names); | |
848 | return swnode; | |
849 | } | |
850 | ||
851 | static void gpio_sim_remove_swnode_recursive(struct fwnode_handle *swnode) | |
852 | { | |
853 | struct fwnode_handle *child; | |
854 | ||
855 | fwnode_for_each_child_node(swnode, child) | |
856 | fwnode_remove_software_node(child); | |
857 | ||
858 | fwnode_remove_software_node(swnode); | |
859 | } | |
860 | ||
861 | static bool gpio_sim_bank_labels_non_unique(struct gpio_sim_device *dev) | |
862 | { | |
863 | struct gpio_sim_bank *this, *pos; | |
864 | ||
865 | list_for_each_entry(this, &dev->bank_list, siblings) { | |
866 | list_for_each_entry(pos, &dev->bank_list, siblings) { | |
867 | if (this == pos || (!this->label || !pos->label)) | |
868 | continue; | |
869 | ||
870 | if (strcmp(this->label, pos->label) == 0) | |
871 | return true; | |
872 | } | |
873 | } | |
874 | ||
875 | return false; | |
876 | } | |
877 | ||
878 | static int gpio_sim_device_activate_unlocked(struct gpio_sim_device *dev) | |
879 | { | |
880 | struct platform_device_info pdevinfo; | |
881 | struct fwnode_handle *swnode; | |
882 | struct platform_device *pdev; | |
883 | struct gpio_sim_bank *bank; | |
884 | int ret; | |
885 | ||
886 | if (list_empty(&dev->bank_list)) | |
887 | return -ENODATA; | |
888 | ||
889 | /* | |
890 | * Non-unique GPIO device labels are a corner-case we don't support | |
891 | * as it would interfere with machine hogging mechanism and has little | |
892 | * use in real life. | |
893 | */ | |
894 | if (gpio_sim_bank_labels_non_unique(dev)) | |
895 | return -EINVAL; | |
896 | ||
897 | memset(&pdevinfo, 0, sizeof(pdevinfo)); | |
898 | ||
899 | swnode = fwnode_create_software_node(NULL, NULL); | |
900 | if (IS_ERR(swnode)) | |
901 | return PTR_ERR(swnode); | |
902 | ||
903 | list_for_each_entry(bank, &dev->bank_list, siblings) { | |
904 | bank->swnode = gpio_sim_make_bank_swnode(bank, swnode); | |
c08995bf TR |
905 | if (IS_ERR(bank->swnode)) { |
906 | ret = PTR_ERR(bank->swnode); | |
cb8c474e BG |
907 | gpio_sim_remove_swnode_recursive(swnode); |
908 | return ret; | |
909 | } | |
910 | } | |
911 | ||
912 | ret = gpio_sim_add_hogs(dev); | |
913 | if (ret) { | |
914 | gpio_sim_remove_swnode_recursive(swnode); | |
915 | return ret; | |
916 | } | |
917 | ||
918 | pdevinfo.name = "gpio-sim"; | |
919 | pdevinfo.fwnode = swnode; | |
920 | pdevinfo.id = dev->id; | |
921 | ||
922 | reinit_completion(&dev->probe_completion); | |
923 | dev->driver_bound = false; | |
924 | bus_register_notifier(&platform_bus_type, &dev->bus_notifier); | |
925 | ||
926 | pdev = platform_device_register_full(&pdevinfo); | |
927 | if (IS_ERR(pdev)) { | |
928 | bus_unregister_notifier(&platform_bus_type, &dev->bus_notifier); | |
929 | gpio_sim_remove_hogs(dev); | |
930 | gpio_sim_remove_swnode_recursive(swnode); | |
931 | return PTR_ERR(pdev); | |
932 | } | |
933 | ||
934 | wait_for_completion(&dev->probe_completion); | |
935 | bus_unregister_notifier(&platform_bus_type, &dev->bus_notifier); | |
936 | ||
937 | if (!dev->driver_bound) { | |
938 | /* Probe failed, check kernel log. */ | |
939 | platform_device_unregister(pdev); | |
940 | gpio_sim_remove_hogs(dev); | |
941 | gpio_sim_remove_swnode_recursive(swnode); | |
942 | return -ENXIO; | |
943 | } | |
944 | ||
945 | dev->pdev = pdev; | |
946 | ||
947 | return 0; | |
948 | } | |
949 | ||
950 | static void gpio_sim_device_deactivate_unlocked(struct gpio_sim_device *dev) | |
951 | { | |
952 | struct fwnode_handle *swnode; | |
953 | ||
954 | swnode = dev_fwnode(&dev->pdev->dev); | |
955 | platform_device_unregister(dev->pdev); | |
0c14f3aa | 956 | gpio_sim_remove_hogs(dev); |
cb8c474e BG |
957 | gpio_sim_remove_swnode_recursive(swnode); |
958 | dev->pdev = NULL; | |
cb8c474e BG |
959 | } |
960 | ||
961 | static ssize_t | |
962 | gpio_sim_device_config_live_store(struct config_item *item, | |
963 | const char *page, size_t count) | |
964 | { | |
965 | struct gpio_sim_device *dev = to_gpio_sim_device(item); | |
966 | bool live; | |
967 | int ret; | |
968 | ||
969 | ret = kstrtobool(page, &live); | |
970 | if (ret) | |
971 | return ret; | |
972 | ||
973 | mutex_lock(&dev->lock); | |
974 | ||
975 | if ((!live && !gpio_sim_device_is_live_unlocked(dev)) || | |
976 | (live && gpio_sim_device_is_live_unlocked(dev))) | |
977 | ret = -EPERM; | |
978 | else if (live) | |
979 | ret = gpio_sim_device_activate_unlocked(dev); | |
980 | else | |
981 | gpio_sim_device_deactivate_unlocked(dev); | |
982 | ||
983 | mutex_unlock(&dev->lock); | |
984 | ||
985 | return ret ?: count; | |
986 | } | |
987 | ||
988 | CONFIGFS_ATTR(gpio_sim_device_config_, live); | |
989 | ||
990 | static struct configfs_attribute *gpio_sim_device_config_attrs[] = { | |
991 | &gpio_sim_device_config_attr_dev_name, | |
992 | &gpio_sim_device_config_attr_live, | |
993 | NULL | |
994 | }; | |
995 | ||
996 | struct gpio_sim_chip_name_ctx { | |
7329b071 | 997 | struct fwnode_handle *swnode; |
cb8c474e BG |
998 | char *page; |
999 | }; | |
1000 | ||
1001 | static int gpio_sim_emit_chip_name(struct device *dev, void *data) | |
1002 | { | |
1003 | struct gpio_sim_chip_name_ctx *ctx = data; | |
cb8c474e BG |
1004 | |
1005 | /* This would be the sysfs device exported in /sys/class/gpio. */ | |
1006 | if (dev->class) | |
1007 | return 0; | |
1008 | ||
7329b071 BG |
1009 | if (device_match_fwnode(dev, ctx->swnode)) |
1010 | return sprintf(ctx->page, "%s\n", dev_name(dev)); | |
cb8c474e | 1011 | |
7329b071 | 1012 | return 0; |
cb8c474e BG |
1013 | } |
1014 | ||
1015 | static ssize_t gpio_sim_bank_config_chip_name_show(struct config_item *item, | |
1016 | char *page) | |
1017 | { | |
1018 | struct gpio_sim_bank *bank = to_gpio_sim_bank(item); | |
1019 | struct gpio_sim_device *dev = gpio_sim_bank_get_device(bank); | |
7329b071 | 1020 | struct gpio_sim_chip_name_ctx ctx = { bank->swnode, page }; |
cb8c474e BG |
1021 | int ret; |
1022 | ||
1023 | mutex_lock(&dev->lock); | |
1024 | if (gpio_sim_device_is_live_unlocked(dev)) | |
1025 | ret = device_for_each_child(&dev->pdev->dev, &ctx, | |
1026 | gpio_sim_emit_chip_name); | |
1027 | else | |
1028 | ret = sprintf(page, "none\n"); | |
1029 | mutex_unlock(&dev->lock); | |
1030 | ||
1031 | return ret; | |
1032 | } | |
1033 | ||
1034 | CONFIGFS_ATTR_RO(gpio_sim_bank_config_, chip_name); | |
1035 | ||
1036 | static ssize_t | |
1037 | gpio_sim_bank_config_label_show(struct config_item *item, char *page) | |
1038 | { | |
1039 | struct gpio_sim_bank *bank = to_gpio_sim_bank(item); | |
1040 | struct gpio_sim_device *dev = gpio_sim_bank_get_device(bank); | |
1041 | int ret; | |
1042 | ||
1043 | mutex_lock(&dev->lock); | |
1044 | ret = sprintf(page, "%s\n", bank->label ?: ""); | |
1045 | mutex_unlock(&dev->lock); | |
1046 | ||
1047 | return ret; | |
1048 | } | |
1049 | ||
1050 | static ssize_t gpio_sim_bank_config_label_store(struct config_item *item, | |
1051 | const char *page, size_t count) | |
1052 | { | |
1053 | struct gpio_sim_bank *bank = to_gpio_sim_bank(item); | |
1054 | struct gpio_sim_device *dev = gpio_sim_bank_get_device(bank); | |
1055 | char *trimmed; | |
1056 | ||
1057 | mutex_lock(&dev->lock); | |
1058 | ||
1059 | if (gpio_sim_device_is_live_unlocked(dev)) { | |
1060 | mutex_unlock(&dev->lock); | |
1061 | return -EBUSY; | |
1062 | } | |
1063 | ||
1064 | trimmed = gpio_sim_strdup_trimmed(page, count); | |
1065 | if (!trimmed) { | |
1066 | mutex_unlock(&dev->lock); | |
1067 | return -ENOMEM; | |
1068 | } | |
1069 | ||
1070 | kfree(bank->label); | |
1071 | bank->label = trimmed; | |
1072 | ||
1073 | mutex_unlock(&dev->lock); | |
1074 | return count; | |
1075 | } | |
1076 | ||
1077 | CONFIGFS_ATTR(gpio_sim_bank_config_, label); | |
1078 | ||
1079 | static ssize_t | |
1080 | gpio_sim_bank_config_num_lines_show(struct config_item *item, char *page) | |
1081 | { | |
1082 | struct gpio_sim_bank *bank = to_gpio_sim_bank(item); | |
1083 | struct gpio_sim_device *dev = gpio_sim_bank_get_device(bank); | |
1084 | int ret; | |
1085 | ||
1086 | mutex_lock(&dev->lock); | |
1087 | ret = sprintf(page, "%u\n", bank->num_lines); | |
1088 | mutex_unlock(&dev->lock); | |
1089 | ||
1090 | return ret; | |
1091 | } | |
1092 | ||
1093 | static ssize_t | |
1094 | gpio_sim_bank_config_num_lines_store(struct config_item *item, | |
1095 | const char *page, size_t count) | |
1096 | { | |
1097 | struct gpio_sim_bank *bank = to_gpio_sim_bank(item); | |
1098 | struct gpio_sim_device *dev = gpio_sim_bank_get_device(bank); | |
1099 | unsigned int num_lines; | |
1100 | int ret; | |
1101 | ||
1102 | ret = kstrtouint(page, 0, &num_lines); | |
1103 | if (ret) | |
1104 | return ret; | |
1105 | ||
1106 | if (num_lines == 0) | |
1107 | return -EINVAL; | |
1108 | ||
1109 | mutex_lock(&dev->lock); | |
1110 | ||
1111 | if (gpio_sim_device_is_live_unlocked(dev)) { | |
1112 | mutex_unlock(&dev->lock); | |
1113 | return -EBUSY; | |
1114 | } | |
1115 | ||
1116 | bank->num_lines = num_lines; | |
1117 | ||
1118 | mutex_unlock(&dev->lock); | |
1119 | return count; | |
1120 | } | |
1121 | ||
1122 | CONFIGFS_ATTR(gpio_sim_bank_config_, num_lines); | |
1123 | ||
1124 | static struct configfs_attribute *gpio_sim_bank_config_attrs[] = { | |
1125 | &gpio_sim_bank_config_attr_chip_name, | |
1126 | &gpio_sim_bank_config_attr_label, | |
1127 | &gpio_sim_bank_config_attr_num_lines, | |
1128 | NULL | |
1129 | }; | |
1130 | ||
1131 | static ssize_t | |
1132 | gpio_sim_line_config_name_show(struct config_item *item, char *page) | |
1133 | { | |
1134 | struct gpio_sim_line *line = to_gpio_sim_line(item); | |
1135 | struct gpio_sim_device *dev = gpio_sim_line_get_device(line); | |
1136 | int ret; | |
1137 | ||
1138 | mutex_lock(&dev->lock); | |
1139 | ret = sprintf(page, "%s\n", line->name ?: ""); | |
1140 | mutex_unlock(&dev->lock); | |
1141 | ||
1142 | return ret; | |
1143 | } | |
1144 | ||
1145 | static ssize_t gpio_sim_line_config_name_store(struct config_item *item, | |
1146 | const char *page, size_t count) | |
1147 | { | |
1148 | struct gpio_sim_line *line = to_gpio_sim_line(item); | |
1149 | struct gpio_sim_device *dev = gpio_sim_line_get_device(line); | |
1150 | char *trimmed; | |
1151 | ||
1152 | mutex_lock(&dev->lock); | |
1153 | ||
1154 | if (gpio_sim_device_is_live_unlocked(dev)) { | |
1155 | mutex_unlock(&dev->lock); | |
1156 | return -EBUSY; | |
1157 | } | |
1158 | ||
1159 | trimmed = gpio_sim_strdup_trimmed(page, count); | |
1160 | if (!trimmed) { | |
1161 | mutex_unlock(&dev->lock); | |
1162 | return -ENOMEM; | |
1163 | } | |
1164 | ||
1165 | kfree(line->name); | |
1166 | line->name = trimmed; | |
1167 | ||
1168 | mutex_unlock(&dev->lock); | |
1169 | ||
1170 | return count; | |
1171 | } | |
1172 | ||
1173 | CONFIGFS_ATTR(gpio_sim_line_config_, name); | |
1174 | ||
1175 | static struct configfs_attribute *gpio_sim_line_config_attrs[] = { | |
1176 | &gpio_sim_line_config_attr_name, | |
1177 | NULL | |
1178 | }; | |
1179 | ||
1180 | static ssize_t gpio_sim_hog_config_name_show(struct config_item *item, | |
1181 | char *page) | |
1182 | { | |
1183 | struct gpio_sim_hog *hog = to_gpio_sim_hog(item); | |
1184 | struct gpio_sim_device *dev = gpio_sim_hog_get_device(hog); | |
1185 | int ret; | |
1186 | ||
1187 | mutex_lock(&dev->lock); | |
1188 | ret = sprintf(page, "%s\n", hog->name ?: ""); | |
1189 | mutex_unlock(&dev->lock); | |
1190 | ||
1191 | return ret; | |
1192 | } | |
1193 | ||
1194 | static ssize_t gpio_sim_hog_config_name_store(struct config_item *item, | |
1195 | const char *page, size_t count) | |
1196 | { | |
1197 | struct gpio_sim_hog *hog = to_gpio_sim_hog(item); | |
1198 | struct gpio_sim_device *dev = gpio_sim_hog_get_device(hog); | |
1199 | char *trimmed; | |
1200 | ||
1201 | mutex_lock(&dev->lock); | |
1202 | ||
1203 | if (gpio_sim_device_is_live_unlocked(dev)) { | |
1204 | mutex_unlock(&dev->lock); | |
1205 | return -EBUSY; | |
1206 | } | |
1207 | ||
1208 | trimmed = gpio_sim_strdup_trimmed(page, count); | |
1209 | if (!trimmed) { | |
1210 | mutex_unlock(&dev->lock); | |
1211 | return -ENOMEM; | |
1212 | } | |
1213 | ||
1214 | kfree(hog->name); | |
1215 | hog->name = trimmed; | |
1216 | ||
1217 | mutex_unlock(&dev->lock); | |
1218 | ||
1219 | return count; | |
1220 | } | |
1221 | ||
1222 | CONFIGFS_ATTR(gpio_sim_hog_config_, name); | |
1223 | ||
1224 | static ssize_t gpio_sim_hog_config_direction_show(struct config_item *item, | |
1225 | char *page) | |
1226 | { | |
1227 | struct gpio_sim_hog *hog = to_gpio_sim_hog(item); | |
1228 | struct gpio_sim_device *dev = gpio_sim_hog_get_device(hog); | |
1229 | char *repr; | |
1230 | int dir; | |
1231 | ||
1232 | mutex_lock(&dev->lock); | |
1233 | dir = hog->dir; | |
1234 | mutex_unlock(&dev->lock); | |
1235 | ||
1236 | switch (dir) { | |
1237 | case GPIOD_IN: | |
1238 | repr = "input"; | |
1239 | break; | |
1240 | case GPIOD_OUT_HIGH: | |
1241 | repr = "output-high"; | |
1242 | break; | |
1243 | case GPIOD_OUT_LOW: | |
1244 | repr = "output-low"; | |
1245 | break; | |
1246 | default: | |
1247 | /* This would be a programmer bug. */ | |
1248 | WARN(1, "Unexpected hog direction value: %d", dir); | |
1249 | return -EINVAL; | |
1250 | } | |
1251 | ||
1252 | return sprintf(page, "%s\n", repr); | |
1253 | } | |
1254 | ||
1255 | static ssize_t | |
1256 | gpio_sim_hog_config_direction_store(struct config_item *item, | |
1257 | const char *page, size_t count) | |
1258 | { | |
1259 | struct gpio_sim_hog *hog = to_gpio_sim_hog(item); | |
1260 | struct gpio_sim_device *dev = gpio_sim_hog_get_device(hog); | |
1261 | char *trimmed; | |
1262 | int dir; | |
1263 | ||
1264 | mutex_lock(&dev->lock); | |
1265 | ||
1266 | if (gpio_sim_device_is_live_unlocked(dev)) { | |
1267 | mutex_unlock(&dev->lock); | |
1268 | return -EBUSY; | |
1269 | } | |
1270 | ||
1271 | trimmed = gpio_sim_strdup_trimmed(page, count); | |
1272 | if (!trimmed) { | |
1273 | mutex_unlock(&dev->lock); | |
1274 | return -ENOMEM; | |
1275 | } | |
1276 | ||
1277 | if (strcmp(trimmed, "input") == 0) | |
1278 | dir = GPIOD_IN; | |
1279 | else if (strcmp(trimmed, "output-high") == 0) | |
1280 | dir = GPIOD_OUT_HIGH; | |
1281 | else if (strcmp(trimmed, "output-low") == 0) | |
1282 | dir = GPIOD_OUT_LOW; | |
1283 | else | |
1284 | dir = -EINVAL; | |
1285 | ||
1286 | kfree(trimmed); | |
1287 | ||
1288 | if (dir < 0) { | |
1289 | mutex_unlock(&dev->lock); | |
1290 | return dir; | |
1291 | } | |
1292 | ||
1293 | hog->dir = dir; | |
1294 | ||
1295 | mutex_unlock(&dev->lock); | |
1296 | ||
1297 | return count; | |
1298 | } | |
1299 | ||
1300 | CONFIGFS_ATTR(gpio_sim_hog_config_, direction); | |
1301 | ||
1302 | static struct configfs_attribute *gpio_sim_hog_config_attrs[] = { | |
1303 | &gpio_sim_hog_config_attr_name, | |
1304 | &gpio_sim_hog_config_attr_direction, | |
1305 | NULL | |
1306 | }; | |
1307 | ||
1308 | static void gpio_sim_hog_config_item_release(struct config_item *item) | |
1309 | { | |
1310 | struct gpio_sim_hog *hog = to_gpio_sim_hog(item); | |
1311 | struct gpio_sim_line *line = hog->parent; | |
1312 | struct gpio_sim_device *dev = gpio_sim_hog_get_device(hog); | |
1313 | ||
1314 | mutex_lock(&dev->lock); | |
1315 | line->hog = NULL; | |
1316 | mutex_unlock(&dev->lock); | |
1317 | ||
1318 | kfree(hog->name); | |
1319 | kfree(hog); | |
1320 | } | |
1321 | ||
a9a5b720 | 1322 | static struct configfs_item_operations gpio_sim_hog_config_item_ops = { |
cb8c474e BG |
1323 | .release = gpio_sim_hog_config_item_release, |
1324 | }; | |
1325 | ||
1326 | static const struct config_item_type gpio_sim_hog_config_type = { | |
1327 | .ct_item_ops = &gpio_sim_hog_config_item_ops, | |
1328 | .ct_attrs = gpio_sim_hog_config_attrs, | |
1329 | .ct_owner = THIS_MODULE, | |
1330 | }; | |
1331 | ||
1332 | static struct config_item * | |
1333 | gpio_sim_line_config_make_hog_item(struct config_group *group, const char *name) | |
1334 | { | |
1335 | struct gpio_sim_line *line = to_gpio_sim_line(&group->cg_item); | |
1336 | struct gpio_sim_device *dev = gpio_sim_line_get_device(line); | |
1337 | struct gpio_sim_hog *hog; | |
1338 | ||
1339 | if (strcmp(name, "hog") != 0) | |
1340 | return ERR_PTR(-EINVAL); | |
1341 | ||
1342 | mutex_lock(&dev->lock); | |
1343 | ||
1344 | hog = kzalloc(sizeof(*hog), GFP_KERNEL); | |
1345 | if (!hog) { | |
1346 | mutex_unlock(&dev->lock); | |
1347 | return ERR_PTR(-ENOMEM); | |
1348 | } | |
1349 | ||
1350 | config_item_init_type_name(&hog->item, name, | |
1351 | &gpio_sim_hog_config_type); | |
1352 | ||
1353 | hog->dir = GPIOD_IN; | |
1354 | hog->name = NULL; | |
1355 | hog->parent = line; | |
1356 | line->hog = hog; | |
1357 | ||
1358 | mutex_unlock(&dev->lock); | |
1359 | ||
1360 | return &hog->item; | |
1361 | } | |
1362 | ||
1363 | static void gpio_sim_line_config_group_release(struct config_item *item) | |
1364 | { | |
1365 | struct gpio_sim_line *line = to_gpio_sim_line(item); | |
1366 | struct gpio_sim_device *dev = gpio_sim_line_get_device(line); | |
1367 | ||
1368 | mutex_lock(&dev->lock); | |
1369 | list_del(&line->siblings); | |
1370 | mutex_unlock(&dev->lock); | |
1371 | ||
1372 | kfree(line->name); | |
1373 | kfree(line); | |
1374 | } | |
1375 | ||
1376 | static struct configfs_item_operations gpio_sim_line_config_item_ops = { | |
1377 | .release = gpio_sim_line_config_group_release, | |
1378 | }; | |
1379 | ||
1380 | static struct configfs_group_operations gpio_sim_line_config_group_ops = { | |
1381 | .make_item = gpio_sim_line_config_make_hog_item, | |
1382 | }; | |
1383 | ||
1384 | static const struct config_item_type gpio_sim_line_config_type = { | |
1385 | .ct_item_ops = &gpio_sim_line_config_item_ops, | |
1386 | .ct_group_ops = &gpio_sim_line_config_group_ops, | |
1387 | .ct_attrs = gpio_sim_line_config_attrs, | |
1388 | .ct_owner = THIS_MODULE, | |
1389 | }; | |
1390 | ||
1391 | static struct config_group * | |
1392 | gpio_sim_bank_config_make_line_group(struct config_group *group, | |
1393 | const char *name) | |
1394 | { | |
1395 | struct gpio_sim_bank *bank = to_gpio_sim_bank(&group->cg_item); | |
1396 | struct gpio_sim_device *dev = gpio_sim_bank_get_device(bank); | |
1397 | struct gpio_sim_line *line; | |
1398 | unsigned int offset; | |
1399 | int ret, nchar; | |
1400 | ||
1401 | ret = sscanf(name, "line%u%n", &offset, &nchar); | |
1402 | if (ret != 1 || nchar != strlen(name)) | |
1403 | return ERR_PTR(-EINVAL); | |
1404 | ||
1405 | mutex_lock(&dev->lock); | |
1406 | ||
1407 | if (gpio_sim_device_is_live_unlocked(dev)) { | |
1408 | mutex_unlock(&dev->lock); | |
1409 | return ERR_PTR(-EBUSY); | |
1410 | } | |
1411 | ||
1412 | line = kzalloc(sizeof(*line), GFP_KERNEL); | |
1413 | if (!line) { | |
1414 | mutex_unlock(&dev->lock); | |
1415 | return ERR_PTR(-ENOMEM); | |
1416 | } | |
1417 | ||
1418 | config_group_init_type_name(&line->group, name, | |
1419 | &gpio_sim_line_config_type); | |
1420 | ||
1421 | line->parent = bank; | |
1422 | line->offset = offset; | |
1423 | list_add_tail(&line->siblings, &bank->line_list); | |
1424 | ||
1425 | mutex_unlock(&dev->lock); | |
1426 | ||
1427 | return &line->group; | |
1428 | } | |
1429 | ||
1430 | static void gpio_sim_bank_config_group_release(struct config_item *item) | |
1431 | { | |
1432 | struct gpio_sim_bank *bank = to_gpio_sim_bank(item); | |
1433 | struct gpio_sim_device *dev = gpio_sim_bank_get_device(bank); | |
1434 | ||
1435 | mutex_lock(&dev->lock); | |
1436 | list_del(&bank->siblings); | |
1437 | mutex_unlock(&dev->lock); | |
1438 | ||
1439 | kfree(bank->label); | |
1440 | kfree(bank); | |
1441 | } | |
1442 | ||
1443 | static struct configfs_item_operations gpio_sim_bank_config_item_ops = { | |
1444 | .release = gpio_sim_bank_config_group_release, | |
1445 | }; | |
1446 | ||
1447 | static struct configfs_group_operations gpio_sim_bank_config_group_ops = { | |
1448 | .make_group = gpio_sim_bank_config_make_line_group, | |
1449 | }; | |
1450 | ||
1451 | static const struct config_item_type gpio_sim_bank_config_group_type = { | |
1452 | .ct_item_ops = &gpio_sim_bank_config_item_ops, | |
1453 | .ct_group_ops = &gpio_sim_bank_config_group_ops, | |
1454 | .ct_attrs = gpio_sim_bank_config_attrs, | |
1455 | .ct_owner = THIS_MODULE, | |
1456 | }; | |
1457 | ||
1458 | static struct config_group * | |
1459 | gpio_sim_device_config_make_bank_group(struct config_group *group, | |
1460 | const char *name) | |
1461 | { | |
1462 | struct gpio_sim_device *dev = to_gpio_sim_device(&group->cg_item); | |
1463 | struct gpio_sim_bank *bank; | |
1464 | ||
1465 | mutex_lock(&dev->lock); | |
1466 | ||
1467 | if (gpio_sim_device_is_live_unlocked(dev)) { | |
1468 | mutex_unlock(&dev->lock); | |
1469 | return ERR_PTR(-EBUSY); | |
1470 | } | |
1471 | ||
1472 | bank = kzalloc(sizeof(*bank), GFP_KERNEL); | |
1473 | if (!bank) { | |
1474 | mutex_unlock(&dev->lock); | |
1475 | return ERR_PTR(-ENOMEM); | |
1476 | } | |
1477 | ||
1478 | config_group_init_type_name(&bank->group, name, | |
1479 | &gpio_sim_bank_config_group_type); | |
1480 | bank->num_lines = 1; | |
1481 | bank->parent = dev; | |
1482 | INIT_LIST_HEAD(&bank->line_list); | |
1483 | list_add_tail(&bank->siblings, &dev->bank_list); | |
1484 | ||
1485 | mutex_unlock(&dev->lock); | |
1486 | ||
1487 | return &bank->group; | |
1488 | } | |
1489 | ||
1490 | static void gpio_sim_device_config_group_release(struct config_item *item) | |
1491 | { | |
1492 | struct gpio_sim_device *dev = to_gpio_sim_device(item); | |
1493 | ||
1494 | mutex_lock(&dev->lock); | |
1495 | if (gpio_sim_device_is_live_unlocked(dev)) | |
1496 | gpio_sim_device_deactivate_unlocked(dev); | |
1497 | mutex_unlock(&dev->lock); | |
1498 | ||
1499 | mutex_destroy(&dev->lock); | |
1500 | ida_free(&gpio_sim_ida, dev->id); | |
1501 | kfree(dev); | |
1502 | } | |
1503 | ||
1504 | static struct configfs_item_operations gpio_sim_device_config_item_ops = { | |
1505 | .release = gpio_sim_device_config_group_release, | |
1506 | }; | |
1507 | ||
1508 | static struct configfs_group_operations gpio_sim_device_config_group_ops = { | |
1509 | .make_group = gpio_sim_device_config_make_bank_group, | |
1510 | }; | |
1511 | ||
1512 | static const struct config_item_type gpio_sim_device_config_group_type = { | |
1513 | .ct_item_ops = &gpio_sim_device_config_item_ops, | |
1514 | .ct_group_ops = &gpio_sim_device_config_group_ops, | |
1515 | .ct_attrs = gpio_sim_device_config_attrs, | |
1516 | .ct_owner = THIS_MODULE, | |
1517 | }; | |
1518 | ||
1519 | static struct config_group * | |
1520 | gpio_sim_config_make_device_group(struct config_group *group, const char *name) | |
1521 | { | |
1522 | struct gpio_sim_device *dev; | |
1523 | int id; | |
1524 | ||
1525 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); | |
1526 | if (!dev) | |
1527 | return ERR_PTR(-ENOMEM); | |
1528 | ||
1529 | id = ida_alloc(&gpio_sim_ida, GFP_KERNEL); | |
1530 | if (id < 0) { | |
1531 | kfree(dev); | |
1532 | return ERR_PTR(id); | |
1533 | } | |
1534 | ||
1535 | config_group_init_type_name(&dev->group, name, | |
1536 | &gpio_sim_device_config_group_type); | |
1537 | dev->id = id; | |
1538 | mutex_init(&dev->lock); | |
1539 | INIT_LIST_HEAD(&dev->bank_list); | |
1540 | ||
1541 | dev->bus_notifier.notifier_call = gpio_sim_bus_notifier_call; | |
1542 | init_completion(&dev->probe_completion); | |
1543 | ||
1544 | return &dev->group; | |
1545 | } | |
1546 | ||
1547 | static struct configfs_group_operations gpio_sim_config_group_ops = { | |
1548 | .make_group = gpio_sim_config_make_device_group, | |
1549 | }; | |
1550 | ||
1551 | static const struct config_item_type gpio_sim_config_type = { | |
1552 | .ct_group_ops = &gpio_sim_config_group_ops, | |
1553 | .ct_owner = THIS_MODULE, | |
1554 | }; | |
1555 | ||
1556 | static struct configfs_subsystem gpio_sim_config_subsys = { | |
1557 | .su_group = { | |
1558 | .cg_item = { | |
1559 | .ci_namebuf = "gpio-sim", | |
1560 | .ci_type = &gpio_sim_config_type, | |
1561 | }, | |
1562 | }, | |
1563 | }; | |
1564 | ||
1565 | static int __init gpio_sim_init(void) | |
1566 | { | |
1567 | int ret; | |
1568 | ||
1569 | ret = platform_driver_register(&gpio_sim_driver); | |
1570 | if (ret) { | |
1571 | pr_err("Error %d while registering the platform driver\n", ret); | |
1572 | return ret; | |
1573 | } | |
1574 | ||
1575 | config_group_init(&gpio_sim_config_subsys.su_group); | |
1576 | mutex_init(&gpio_sim_config_subsys.su_mutex); | |
1577 | ret = configfs_register_subsystem(&gpio_sim_config_subsys); | |
1578 | if (ret) { | |
1579 | pr_err("Error %d while registering the configfs subsystem %s\n", | |
1580 | ret, gpio_sim_config_subsys.su_group.cg_item.ci_namebuf); | |
1581 | mutex_destroy(&gpio_sim_config_subsys.su_mutex); | |
1582 | platform_driver_unregister(&gpio_sim_driver); | |
1583 | return ret; | |
1584 | } | |
1585 | ||
1586 | return 0; | |
1587 | } | |
1588 | module_init(gpio_sim_init); | |
1589 | ||
1590 | static void __exit gpio_sim_exit(void) | |
1591 | { | |
1592 | configfs_unregister_subsystem(&gpio_sim_config_subsys); | |
1593 | mutex_destroy(&gpio_sim_config_subsys.su_mutex); | |
1594 | platform_driver_unregister(&gpio_sim_driver); | |
1595 | } | |
1596 | module_exit(gpio_sim_exit); | |
1597 | ||
1598 | MODULE_AUTHOR("Bartosz Golaszewski <brgl@bgdev.pl"); | |
1599 | MODULE_DESCRIPTION("GPIO Simulator Module"); | |
1600 | MODULE_LICENSE("GPL"); |