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1 | /* | |
2 | * Driver for keys on GPIO lines capable of generating interrupts. | |
3 | * | |
4 | * Copyright 2005 Phil Blundell | |
5 | * Copyright 2010, 2011 David Jander <david@protonic.nl> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | */ | |
11 | ||
12 | #include <linux/module.h> | |
13 | ||
14 | #include <linux/init.h> | |
15 | #include <linux/fs.h> | |
16 | #include <linux/interrupt.h> | |
17 | #include <linux/irq.h> | |
18 | #include <linux/sched.h> | |
19 | #include <linux/pm.h> | |
20 | #include <linux/slab.h> | |
21 | #include <linux/sysctl.h> | |
22 | #include <linux/proc_fs.h> | |
23 | #include <linux/delay.h> | |
24 | #include <linux/platform_device.h> | |
25 | #include <linux/input.h> | |
26 | #include <linux/gpio_keys.h> | |
27 | #include <linux/workqueue.h> | |
28 | #include <linux/gpio.h> | |
29 | #include <linux/gpio/consumer.h> | |
30 | #include <linux/of.h> | |
31 | #include <linux/of_irq.h> | |
32 | #include <linux/spinlock.h> | |
33 | ||
34 | struct gpio_button_data { | |
35 | const struct gpio_keys_button *button; | |
36 | struct input_dev *input; | |
37 | struct gpio_desc *gpiod; | |
38 | ||
39 | struct timer_list release_timer; | |
40 | unsigned int release_delay; /* in msecs, for IRQ-only buttons */ | |
41 | ||
42 | struct delayed_work work; | |
43 | unsigned int software_debounce; /* in msecs, for GPIO-driven buttons */ | |
44 | ||
45 | unsigned int irq; | |
46 | spinlock_t lock; | |
47 | bool disabled; | |
48 | bool key_pressed; | |
49 | }; | |
50 | ||
51 | struct gpio_keys_drvdata { | |
52 | const struct gpio_keys_platform_data *pdata; | |
53 | struct input_dev *input; | |
54 | struct mutex disable_lock; | |
55 | struct gpio_button_data data[0]; | |
56 | }; | |
57 | ||
58 | /* | |
59 | * SYSFS interface for enabling/disabling keys and switches: | |
60 | * | |
61 | * There are 4 attributes under /sys/devices/platform/gpio-keys/ | |
62 | * keys [ro] - bitmap of keys (EV_KEY) which can be | |
63 | * disabled | |
64 | * switches [ro] - bitmap of switches (EV_SW) which can be | |
65 | * disabled | |
66 | * disabled_keys [rw] - bitmap of keys currently disabled | |
67 | * disabled_switches [rw] - bitmap of switches currently disabled | |
68 | * | |
69 | * Userland can change these values and hence disable event generation | |
70 | * for each key (or switch). Disabling a key means its interrupt line | |
71 | * is disabled. | |
72 | * | |
73 | * For example, if we have following switches set up as gpio-keys: | |
74 | * SW_DOCK = 5 | |
75 | * SW_CAMERA_LENS_COVER = 9 | |
76 | * SW_KEYPAD_SLIDE = 10 | |
77 | * SW_FRONT_PROXIMITY = 11 | |
78 | * This is read from switches: | |
79 | * 11-9,5 | |
80 | * Next we want to disable proximity (11) and dock (5), we write: | |
81 | * 11,5 | |
82 | * to file disabled_switches. Now proximity and dock IRQs are disabled. | |
83 | * This can be verified by reading the file disabled_switches: | |
84 | * 11,5 | |
85 | * If we now want to enable proximity (11) switch we write: | |
86 | * 5 | |
87 | * to disabled_switches. | |
88 | * | |
89 | * We can disable only those keys which don't allow sharing the irq. | |
90 | */ | |
91 | ||
92 | /** | |
93 | * get_n_events_by_type() - returns maximum number of events per @type | |
94 | * @type: type of button (%EV_KEY, %EV_SW) | |
95 | * | |
96 | * Return value of this function can be used to allocate bitmap | |
97 | * large enough to hold all bits for given type. | |
98 | */ | |
99 | static int get_n_events_by_type(int type) | |
100 | { | |
101 | BUG_ON(type != EV_SW && type != EV_KEY); | |
102 | ||
103 | return (type == EV_KEY) ? KEY_CNT : SW_CNT; | |
104 | } | |
105 | ||
106 | /** | |
107 | * get_bm_events_by_type() - returns bitmap of supported events per @type | |
108 | * @input: input device from which bitmap is retrieved | |
109 | * @type: type of button (%EV_KEY, %EV_SW) | |
110 | * | |
111 | * Return value of this function can be used to allocate bitmap | |
112 | * large enough to hold all bits for given type. | |
113 | */ | |
114 | static const unsigned long *get_bm_events_by_type(struct input_dev *dev, | |
115 | int type) | |
116 | { | |
117 | BUG_ON(type != EV_SW && type != EV_KEY); | |
118 | ||
119 | return (type == EV_KEY) ? dev->keybit : dev->swbit; | |
120 | } | |
121 | ||
122 | /** | |
123 | * gpio_keys_disable_button() - disables given GPIO button | |
124 | * @bdata: button data for button to be disabled | |
125 | * | |
126 | * Disables button pointed by @bdata. This is done by masking | |
127 | * IRQ line. After this function is called, button won't generate | |
128 | * input events anymore. Note that one can only disable buttons | |
129 | * that don't share IRQs. | |
130 | * | |
131 | * Make sure that @bdata->disable_lock is locked when entering | |
132 | * this function to avoid races when concurrent threads are | |
133 | * disabling buttons at the same time. | |
134 | */ | |
135 | static void gpio_keys_disable_button(struct gpio_button_data *bdata) | |
136 | { | |
137 | if (!bdata->disabled) { | |
138 | /* | |
139 | * Disable IRQ and associated timer/work structure. | |
140 | */ | |
141 | disable_irq(bdata->irq); | |
142 | ||
143 | if (bdata->gpiod) | |
144 | cancel_delayed_work_sync(&bdata->work); | |
145 | else | |
146 | del_timer_sync(&bdata->release_timer); | |
147 | ||
148 | bdata->disabled = true; | |
149 | } | |
150 | } | |
151 | ||
152 | /** | |
153 | * gpio_keys_enable_button() - enables given GPIO button | |
154 | * @bdata: button data for button to be disabled | |
155 | * | |
156 | * Enables given button pointed by @bdata. | |
157 | * | |
158 | * Make sure that @bdata->disable_lock is locked when entering | |
159 | * this function to avoid races with concurrent threads trying | |
160 | * to enable the same button at the same time. | |
161 | */ | |
162 | static void gpio_keys_enable_button(struct gpio_button_data *bdata) | |
163 | { | |
164 | if (bdata->disabled) { | |
165 | enable_irq(bdata->irq); | |
166 | bdata->disabled = false; | |
167 | } | |
168 | } | |
169 | ||
170 | /** | |
171 | * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons | |
172 | * @ddata: pointer to drvdata | |
173 | * @buf: buffer where stringified bitmap is written | |
174 | * @type: button type (%EV_KEY, %EV_SW) | |
175 | * @only_disabled: does caller want only those buttons that are | |
176 | * currently disabled or all buttons that can be | |
177 | * disabled | |
178 | * | |
179 | * This function writes buttons that can be disabled to @buf. If | |
180 | * @only_disabled is true, then @buf contains only those buttons | |
181 | * that are currently disabled. Returns 0 on success or negative | |
182 | * errno on failure. | |
183 | */ | |
184 | static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata, | |
185 | char *buf, unsigned int type, | |
186 | bool only_disabled) | |
187 | { | |
188 | int n_events = get_n_events_by_type(type); | |
189 | unsigned long *bits; | |
190 | ssize_t ret; | |
191 | int i; | |
192 | ||
193 | bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL); | |
194 | if (!bits) | |
195 | return -ENOMEM; | |
196 | ||
197 | for (i = 0; i < ddata->pdata->nbuttons; i++) { | |
198 | struct gpio_button_data *bdata = &ddata->data[i]; | |
199 | ||
200 | if (bdata->button->type != type) | |
201 | continue; | |
202 | ||
203 | if (only_disabled && !bdata->disabled) | |
204 | continue; | |
205 | ||
206 | __set_bit(bdata->button->code, bits); | |
207 | } | |
208 | ||
209 | ret = scnprintf(buf, PAGE_SIZE - 1, "%*pbl", n_events, bits); | |
210 | buf[ret++] = '\n'; | |
211 | buf[ret] = '\0'; | |
212 | ||
213 | kfree(bits); | |
214 | ||
215 | return ret; | |
216 | } | |
217 | ||
218 | /** | |
219 | * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap | |
220 | * @ddata: pointer to drvdata | |
221 | * @buf: buffer from userspace that contains stringified bitmap | |
222 | * @type: button type (%EV_KEY, %EV_SW) | |
223 | * | |
224 | * This function parses stringified bitmap from @buf and disables/enables | |
225 | * GPIO buttons accordingly. Returns 0 on success and negative error | |
226 | * on failure. | |
227 | */ | |
228 | static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata, | |
229 | const char *buf, unsigned int type) | |
230 | { | |
231 | int n_events = get_n_events_by_type(type); | |
232 | const unsigned long *bitmap = get_bm_events_by_type(ddata->input, type); | |
233 | unsigned long *bits; | |
234 | ssize_t error; | |
235 | int i; | |
236 | ||
237 | bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL); | |
238 | if (!bits) | |
239 | return -ENOMEM; | |
240 | ||
241 | error = bitmap_parselist(buf, bits, n_events); | |
242 | if (error) | |
243 | goto out; | |
244 | ||
245 | /* First validate */ | |
246 | if (!bitmap_subset(bits, bitmap, n_events)) { | |
247 | error = -EINVAL; | |
248 | goto out; | |
249 | } | |
250 | ||
251 | for (i = 0; i < ddata->pdata->nbuttons; i++) { | |
252 | struct gpio_button_data *bdata = &ddata->data[i]; | |
253 | ||
254 | if (bdata->button->type != type) | |
255 | continue; | |
256 | ||
257 | if (test_bit(bdata->button->code, bits) && | |
258 | !bdata->button->can_disable) { | |
259 | error = -EINVAL; | |
260 | goto out; | |
261 | } | |
262 | } | |
263 | ||
264 | mutex_lock(&ddata->disable_lock); | |
265 | ||
266 | for (i = 0; i < ddata->pdata->nbuttons; i++) { | |
267 | struct gpio_button_data *bdata = &ddata->data[i]; | |
268 | ||
269 | if (bdata->button->type != type) | |
270 | continue; | |
271 | ||
272 | if (test_bit(bdata->button->code, bits)) | |
273 | gpio_keys_disable_button(bdata); | |
274 | else | |
275 | gpio_keys_enable_button(bdata); | |
276 | } | |
277 | ||
278 | mutex_unlock(&ddata->disable_lock); | |
279 | ||
280 | out: | |
281 | kfree(bits); | |
282 | return error; | |
283 | } | |
284 | ||
285 | #define ATTR_SHOW_FN(name, type, only_disabled) \ | |
286 | static ssize_t gpio_keys_show_##name(struct device *dev, \ | |
287 | struct device_attribute *attr, \ | |
288 | char *buf) \ | |
289 | { \ | |
290 | struct platform_device *pdev = to_platform_device(dev); \ | |
291 | struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ | |
292 | \ | |
293 | return gpio_keys_attr_show_helper(ddata, buf, \ | |
294 | type, only_disabled); \ | |
295 | } | |
296 | ||
297 | ATTR_SHOW_FN(keys, EV_KEY, false); | |
298 | ATTR_SHOW_FN(switches, EV_SW, false); | |
299 | ATTR_SHOW_FN(disabled_keys, EV_KEY, true); | |
300 | ATTR_SHOW_FN(disabled_switches, EV_SW, true); | |
301 | ||
302 | /* | |
303 | * ATTRIBUTES: | |
304 | * | |
305 | * /sys/devices/platform/gpio-keys/keys [ro] | |
306 | * /sys/devices/platform/gpio-keys/switches [ro] | |
307 | */ | |
308 | static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL); | |
309 | static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL); | |
310 | ||
311 | #define ATTR_STORE_FN(name, type) \ | |
312 | static ssize_t gpio_keys_store_##name(struct device *dev, \ | |
313 | struct device_attribute *attr, \ | |
314 | const char *buf, \ | |
315 | size_t count) \ | |
316 | { \ | |
317 | struct platform_device *pdev = to_platform_device(dev); \ | |
318 | struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ | |
319 | ssize_t error; \ | |
320 | \ | |
321 | error = gpio_keys_attr_store_helper(ddata, buf, type); \ | |
322 | if (error) \ | |
323 | return error; \ | |
324 | \ | |
325 | return count; \ | |
326 | } | |
327 | ||
328 | ATTR_STORE_FN(disabled_keys, EV_KEY); | |
329 | ATTR_STORE_FN(disabled_switches, EV_SW); | |
330 | ||
331 | /* | |
332 | * ATTRIBUTES: | |
333 | * | |
334 | * /sys/devices/platform/gpio-keys/disabled_keys [rw] | |
335 | * /sys/devices/platform/gpio-keys/disables_switches [rw] | |
336 | */ | |
337 | static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO, | |
338 | gpio_keys_show_disabled_keys, | |
339 | gpio_keys_store_disabled_keys); | |
340 | static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO, | |
341 | gpio_keys_show_disabled_switches, | |
342 | gpio_keys_store_disabled_switches); | |
343 | ||
344 | static struct attribute *gpio_keys_attrs[] = { | |
345 | &dev_attr_keys.attr, | |
346 | &dev_attr_switches.attr, | |
347 | &dev_attr_disabled_keys.attr, | |
348 | &dev_attr_disabled_switches.attr, | |
349 | NULL, | |
350 | }; | |
351 | ||
352 | static struct attribute_group gpio_keys_attr_group = { | |
353 | .attrs = gpio_keys_attrs, | |
354 | }; | |
355 | ||
356 | static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata) | |
357 | { | |
358 | const struct gpio_keys_button *button = bdata->button; | |
359 | struct input_dev *input = bdata->input; | |
360 | unsigned int type = button->type ?: EV_KEY; | |
361 | int state; | |
362 | ||
363 | state = gpiod_get_value_cansleep(bdata->gpiod); | |
364 | if (state < 0) { | |
365 | dev_err(input->dev.parent, | |
366 | "failed to get gpio state: %d\n", state); | |
367 | return; | |
368 | } | |
369 | ||
370 | if (type == EV_ABS) { | |
371 | if (state) | |
372 | input_event(input, type, button->code, button->value); | |
373 | } else { | |
374 | input_event(input, type, button->code, state); | |
375 | } | |
376 | input_sync(input); | |
377 | } | |
378 | ||
379 | static void gpio_keys_gpio_work_func(struct work_struct *work) | |
380 | { | |
381 | struct gpio_button_data *bdata = | |
382 | container_of(work, struct gpio_button_data, work.work); | |
383 | ||
384 | gpio_keys_gpio_report_event(bdata); | |
385 | ||
386 | if (bdata->button->wakeup) | |
387 | pm_relax(bdata->input->dev.parent); | |
388 | } | |
389 | ||
390 | static irqreturn_t gpio_keys_gpio_isr(int irq, void *dev_id) | |
391 | { | |
392 | struct gpio_button_data *bdata = dev_id; | |
393 | ||
394 | BUG_ON(irq != bdata->irq); | |
395 | ||
396 | if (bdata->button->wakeup) | |
397 | pm_stay_awake(bdata->input->dev.parent); | |
398 | ||
399 | mod_delayed_work(system_wq, | |
400 | &bdata->work, | |
401 | msecs_to_jiffies(bdata->software_debounce)); | |
402 | ||
403 | return IRQ_HANDLED; | |
404 | } | |
405 | ||
406 | static void gpio_keys_irq_timer(unsigned long _data) | |
407 | { | |
408 | struct gpio_button_data *bdata = (struct gpio_button_data *)_data; | |
409 | struct input_dev *input = bdata->input; | |
410 | unsigned long flags; | |
411 | ||
412 | spin_lock_irqsave(&bdata->lock, flags); | |
413 | if (bdata->key_pressed) { | |
414 | input_event(input, EV_KEY, bdata->button->code, 0); | |
415 | input_sync(input); | |
416 | bdata->key_pressed = false; | |
417 | } | |
418 | spin_unlock_irqrestore(&bdata->lock, flags); | |
419 | } | |
420 | ||
421 | static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) | |
422 | { | |
423 | struct gpio_button_data *bdata = dev_id; | |
424 | const struct gpio_keys_button *button = bdata->button; | |
425 | struct input_dev *input = bdata->input; | |
426 | unsigned long flags; | |
427 | ||
428 | BUG_ON(irq != bdata->irq); | |
429 | ||
430 | spin_lock_irqsave(&bdata->lock, flags); | |
431 | ||
432 | if (!bdata->key_pressed) { | |
433 | if (bdata->button->wakeup) | |
434 | pm_wakeup_event(bdata->input->dev.parent, 0); | |
435 | ||
436 | input_event(input, EV_KEY, button->code, 1); | |
437 | input_sync(input); | |
438 | ||
439 | if (!bdata->release_delay) { | |
440 | input_event(input, EV_KEY, button->code, 0); | |
441 | input_sync(input); | |
442 | goto out; | |
443 | } | |
444 | ||
445 | bdata->key_pressed = true; | |
446 | } | |
447 | ||
448 | if (bdata->release_delay) | |
449 | mod_timer(&bdata->release_timer, | |
450 | jiffies + msecs_to_jiffies(bdata->release_delay)); | |
451 | out: | |
452 | spin_unlock_irqrestore(&bdata->lock, flags); | |
453 | return IRQ_HANDLED; | |
454 | } | |
455 | ||
456 | static void gpio_keys_quiesce_key(void *data) | |
457 | { | |
458 | struct gpio_button_data *bdata = data; | |
459 | ||
460 | if (bdata->gpiod) | |
461 | cancel_delayed_work_sync(&bdata->work); | |
462 | else | |
463 | del_timer_sync(&bdata->release_timer); | |
464 | } | |
465 | ||
466 | static int gpio_keys_setup_key(struct platform_device *pdev, | |
467 | struct input_dev *input, | |
468 | struct gpio_button_data *bdata, | |
469 | const struct gpio_keys_button *button, | |
470 | struct fwnode_handle *child) | |
471 | { | |
472 | const char *desc = button->desc ? button->desc : "gpio_keys"; | |
473 | struct device *dev = &pdev->dev; | |
474 | irq_handler_t isr; | |
475 | unsigned long irqflags; | |
476 | int irq; | |
477 | int error; | |
478 | ||
479 | bdata->input = input; | |
480 | bdata->button = button; | |
481 | spin_lock_init(&bdata->lock); | |
482 | ||
483 | if (child) { | |
484 | bdata->gpiod = devm_get_gpiod_from_child(dev, NULL, child); | |
485 | if (IS_ERR(bdata->gpiod)) { | |
486 | error = PTR_ERR(bdata->gpiod); | |
487 | if (error == -ENOENT) { | |
488 | /* | |
489 | * GPIO is optional, we may be dealing with | |
490 | * purely interrupt-driven setup. | |
491 | */ | |
492 | bdata->gpiod = NULL; | |
493 | } else { | |
494 | if (error != -EPROBE_DEFER) | |
495 | dev_err(dev, "failed to get gpio: %d\n", | |
496 | error); | |
497 | return error; | |
498 | } | |
499 | } else { | |
500 | error = gpiod_direction_input(bdata->gpiod); | |
501 | if (error) { | |
502 | dev_err(dev, "Failed to configure GPIO %d as input: %d\n", | |
503 | desc_to_gpio(bdata->gpiod), error); | |
504 | return error; | |
505 | } | |
506 | } | |
507 | } else if (gpio_is_valid(button->gpio)) { | |
508 | /* | |
509 | * Legacy GPIO number, so request the GPIO here and | |
510 | * convert it to descriptor. | |
511 | */ | |
512 | unsigned flags = GPIOF_IN; | |
513 | ||
514 | if (button->active_low) | |
515 | flags |= GPIOF_ACTIVE_LOW; | |
516 | ||
517 | error = devm_gpio_request_one(&pdev->dev, button->gpio, flags, | |
518 | desc); | |
519 | if (error < 0) { | |
520 | dev_err(dev, "Failed to request GPIO %d, error %d\n", | |
521 | button->gpio, error); | |
522 | return error; | |
523 | } | |
524 | ||
525 | bdata->gpiod = gpio_to_desc(button->gpio); | |
526 | if (!bdata->gpiod) | |
527 | return -EINVAL; | |
528 | } | |
529 | ||
530 | if (bdata->gpiod) { | |
531 | if (button->debounce_interval) { | |
532 | error = gpiod_set_debounce(bdata->gpiod, | |
533 | button->debounce_interval * 1000); | |
534 | /* use timer if gpiolib doesn't provide debounce */ | |
535 | if (error < 0) | |
536 | bdata->software_debounce = | |
537 | button->debounce_interval; | |
538 | } | |
539 | ||
540 | if (button->irq) { | |
541 | bdata->irq = button->irq; | |
542 | } else { | |
543 | irq = gpiod_to_irq(bdata->gpiod); | |
544 | if (irq < 0) { | |
545 | error = irq; | |
546 | dev_err(dev, | |
547 | "Unable to get irq number for GPIO %d, error %d\n", | |
548 | button->gpio, error); | |
549 | return error; | |
550 | } | |
551 | bdata->irq = irq; | |
552 | } | |
553 | ||
554 | INIT_DELAYED_WORK(&bdata->work, gpio_keys_gpio_work_func); | |
555 | ||
556 | isr = gpio_keys_gpio_isr; | |
557 | irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING; | |
558 | ||
559 | } else { | |
560 | if (!button->irq) { | |
561 | dev_err(dev, "Found button without gpio or irq\n"); | |
562 | return -EINVAL; | |
563 | } | |
564 | ||
565 | bdata->irq = button->irq; | |
566 | ||
567 | if (button->type && button->type != EV_KEY) { | |
568 | dev_err(dev, "Only EV_KEY allowed for IRQ buttons.\n"); | |
569 | return -EINVAL; | |
570 | } | |
571 | ||
572 | bdata->release_delay = button->debounce_interval; | |
573 | setup_timer(&bdata->release_timer, | |
574 | gpio_keys_irq_timer, (unsigned long)bdata); | |
575 | ||
576 | isr = gpio_keys_irq_isr; | |
577 | irqflags = 0; | |
578 | } | |
579 | ||
580 | input_set_capability(input, button->type ?: EV_KEY, button->code); | |
581 | ||
582 | /* | |
583 | * Install custom action to cancel release timer and | |
584 | * workqueue item. | |
585 | */ | |
586 | error = devm_add_action(&pdev->dev, gpio_keys_quiesce_key, bdata); | |
587 | if (error) { | |
588 | dev_err(&pdev->dev, | |
589 | "failed to register quiesce action, error: %d\n", | |
590 | error); | |
591 | return error; | |
592 | } | |
593 | ||
594 | /* | |
595 | * If platform has specified that the button can be disabled, | |
596 | * we don't want it to share the interrupt line. | |
597 | */ | |
598 | if (!button->can_disable) | |
599 | irqflags |= IRQF_SHARED; | |
600 | ||
601 | error = devm_request_any_context_irq(&pdev->dev, bdata->irq, | |
602 | isr, irqflags, desc, bdata); | |
603 | if (error < 0) { | |
604 | dev_err(dev, "Unable to claim irq %d; error %d\n", | |
605 | bdata->irq, error); | |
606 | return error; | |
607 | } | |
608 | ||
609 | return 0; | |
610 | } | |
611 | ||
612 | static void gpio_keys_report_state(struct gpio_keys_drvdata *ddata) | |
613 | { | |
614 | struct input_dev *input = ddata->input; | |
615 | int i; | |
616 | ||
617 | for (i = 0; i < ddata->pdata->nbuttons; i++) { | |
618 | struct gpio_button_data *bdata = &ddata->data[i]; | |
619 | if (bdata->gpiod) | |
620 | gpio_keys_gpio_report_event(bdata); | |
621 | } | |
622 | input_sync(input); | |
623 | } | |
624 | ||
625 | static int gpio_keys_open(struct input_dev *input) | |
626 | { | |
627 | struct gpio_keys_drvdata *ddata = input_get_drvdata(input); | |
628 | const struct gpio_keys_platform_data *pdata = ddata->pdata; | |
629 | int error; | |
630 | ||
631 | if (pdata->enable) { | |
632 | error = pdata->enable(input->dev.parent); | |
633 | if (error) | |
634 | return error; | |
635 | } | |
636 | ||
637 | /* Report current state of buttons that are connected to GPIOs */ | |
638 | gpio_keys_report_state(ddata); | |
639 | ||
640 | return 0; | |
641 | } | |
642 | ||
643 | static void gpio_keys_close(struct input_dev *input) | |
644 | { | |
645 | struct gpio_keys_drvdata *ddata = input_get_drvdata(input); | |
646 | const struct gpio_keys_platform_data *pdata = ddata->pdata; | |
647 | ||
648 | if (pdata->disable) | |
649 | pdata->disable(input->dev.parent); | |
650 | } | |
651 | ||
652 | /* | |
653 | * Handlers for alternative sources of platform_data | |
654 | */ | |
655 | ||
656 | /* | |
657 | * Translate properties into platform_data | |
658 | */ | |
659 | static struct gpio_keys_platform_data * | |
660 | gpio_keys_get_devtree_pdata(struct device *dev) | |
661 | { | |
662 | struct gpio_keys_platform_data *pdata; | |
663 | struct gpio_keys_button *button; | |
664 | struct fwnode_handle *child; | |
665 | int nbuttons; | |
666 | ||
667 | nbuttons = device_get_child_node_count(dev); | |
668 | if (nbuttons == 0) | |
669 | return ERR_PTR(-ENODEV); | |
670 | ||
671 | pdata = devm_kzalloc(dev, | |
672 | sizeof(*pdata) + nbuttons * sizeof(*button), | |
673 | GFP_KERNEL); | |
674 | if (!pdata) | |
675 | return ERR_PTR(-ENOMEM); | |
676 | ||
677 | button = (struct gpio_keys_button *)(pdata + 1); | |
678 | ||
679 | pdata->buttons = button; | |
680 | pdata->nbuttons = nbuttons; | |
681 | ||
682 | pdata->rep = device_property_read_bool(dev, "autorepeat"); | |
683 | ||
684 | device_property_read_string(dev, "label", &pdata->name); | |
685 | ||
686 | device_for_each_child_node(dev, child) { | |
687 | if (is_of_node(child)) | |
688 | button->irq = | |
689 | irq_of_parse_and_map(to_of_node(child), 0); | |
690 | ||
691 | if (fwnode_property_read_u32(child, "linux,code", | |
692 | &button->code)) { | |
693 | dev_err(dev, "Button without keycode\n"); | |
694 | fwnode_handle_put(child); | |
695 | return ERR_PTR(-EINVAL); | |
696 | } | |
697 | ||
698 | fwnode_property_read_string(child, "label", &button->desc); | |
699 | ||
700 | if (fwnode_property_read_u32(child, "linux,input-type", | |
701 | &button->type)) | |
702 | button->type = EV_KEY; | |
703 | ||
704 | button->wakeup = | |
705 | fwnode_property_read_bool(child, "wakeup-source") || | |
706 | /* legacy name */ | |
707 | fwnode_property_read_bool(child, "gpio-key,wakeup"); | |
708 | ||
709 | button->can_disable = | |
710 | fwnode_property_read_bool(child, "linux,can-disable"); | |
711 | ||
712 | if (fwnode_property_read_u32(child, "debounce-interval", | |
713 | &button->debounce_interval)) | |
714 | button->debounce_interval = 5; | |
715 | ||
716 | button++; | |
717 | } | |
718 | ||
719 | return pdata; | |
720 | } | |
721 | ||
722 | static const struct of_device_id gpio_keys_of_match[] = { | |
723 | { .compatible = "gpio-keys", }, | |
724 | { }, | |
725 | }; | |
726 | MODULE_DEVICE_TABLE(of, gpio_keys_of_match); | |
727 | ||
728 | static int gpio_keys_probe(struct platform_device *pdev) | |
729 | { | |
730 | struct device *dev = &pdev->dev; | |
731 | const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev); | |
732 | struct fwnode_handle *child = NULL; | |
733 | struct gpio_keys_drvdata *ddata; | |
734 | struct input_dev *input; | |
735 | size_t size; | |
736 | int i, error; | |
737 | int wakeup = 0; | |
738 | ||
739 | if (!pdata) { | |
740 | pdata = gpio_keys_get_devtree_pdata(dev); | |
741 | if (IS_ERR(pdata)) | |
742 | return PTR_ERR(pdata); | |
743 | } | |
744 | ||
745 | size = sizeof(struct gpio_keys_drvdata) + | |
746 | pdata->nbuttons * sizeof(struct gpio_button_data); | |
747 | ddata = devm_kzalloc(dev, size, GFP_KERNEL); | |
748 | if (!ddata) { | |
749 | dev_err(dev, "failed to allocate state\n"); | |
750 | return -ENOMEM; | |
751 | } | |
752 | ||
753 | input = devm_input_allocate_device(dev); | |
754 | if (!input) { | |
755 | dev_err(dev, "failed to allocate input device\n"); | |
756 | return -ENOMEM; | |
757 | } | |
758 | ||
759 | ddata->pdata = pdata; | |
760 | ddata->input = input; | |
761 | mutex_init(&ddata->disable_lock); | |
762 | ||
763 | platform_set_drvdata(pdev, ddata); | |
764 | input_set_drvdata(input, ddata); | |
765 | ||
766 | input->name = pdata->name ? : pdev->name; | |
767 | input->phys = "gpio-keys/input0"; | |
768 | input->dev.parent = &pdev->dev; | |
769 | input->open = gpio_keys_open; | |
770 | input->close = gpio_keys_close; | |
771 | ||
772 | input->id.bustype = BUS_HOST; | |
773 | input->id.vendor = 0x0001; | |
774 | input->id.product = 0x0001; | |
775 | input->id.version = 0x0100; | |
776 | ||
777 | /* Enable auto repeat feature of Linux input subsystem */ | |
778 | if (pdata->rep) | |
779 | __set_bit(EV_REP, input->evbit); | |
780 | ||
781 | for (i = 0; i < pdata->nbuttons; i++) { | |
782 | const struct gpio_keys_button *button = &pdata->buttons[i]; | |
783 | struct gpio_button_data *bdata = &ddata->data[i]; | |
784 | ||
785 | if (!dev_get_platdata(dev)) { | |
786 | child = device_get_next_child_node(&pdev->dev, child); | |
787 | if (!child) { | |
788 | dev_err(&pdev->dev, | |
789 | "missing child device node for entry %d\n", | |
790 | i); | |
791 | return -EINVAL; | |
792 | } | |
793 | } | |
794 | ||
795 | error = gpio_keys_setup_key(pdev, input, bdata, button, child); | |
796 | if (error) { | |
797 | fwnode_handle_put(child); | |
798 | return error; | |
799 | } | |
800 | ||
801 | if (button->wakeup) | |
802 | wakeup = 1; | |
803 | } | |
804 | ||
805 | fwnode_handle_put(child); | |
806 | ||
807 | error = sysfs_create_group(&pdev->dev.kobj, &gpio_keys_attr_group); | |
808 | if (error) { | |
809 | dev_err(dev, "Unable to export keys/switches, error: %d\n", | |
810 | error); | |
811 | return error; | |
812 | } | |
813 | ||
814 | error = input_register_device(input); | |
815 | if (error) { | |
816 | dev_err(dev, "Unable to register input device, error: %d\n", | |
817 | error); | |
818 | goto err_remove_group; | |
819 | } | |
820 | ||
821 | device_init_wakeup(&pdev->dev, wakeup); | |
822 | ||
823 | return 0; | |
824 | ||
825 | err_remove_group: | |
826 | sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group); | |
827 | return error; | |
828 | } | |
829 | ||
830 | static int gpio_keys_remove(struct platform_device *pdev) | |
831 | { | |
832 | sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group); | |
833 | ||
834 | device_init_wakeup(&pdev->dev, 0); | |
835 | ||
836 | return 0; | |
837 | } | |
838 | ||
839 | static int __maybe_unused gpio_keys_suspend(struct device *dev) | |
840 | { | |
841 | struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); | |
842 | struct input_dev *input = ddata->input; | |
843 | int i; | |
844 | ||
845 | if (device_may_wakeup(dev)) { | |
846 | for (i = 0; i < ddata->pdata->nbuttons; i++) { | |
847 | struct gpio_button_data *bdata = &ddata->data[i]; | |
848 | if (bdata->button->wakeup) | |
849 | enable_irq_wake(bdata->irq); | |
850 | } | |
851 | } else { | |
852 | mutex_lock(&input->mutex); | |
853 | if (input->users) | |
854 | gpio_keys_close(input); | |
855 | mutex_unlock(&input->mutex); | |
856 | } | |
857 | ||
858 | return 0; | |
859 | } | |
860 | ||
861 | static int __maybe_unused gpio_keys_resume(struct device *dev) | |
862 | { | |
863 | struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); | |
864 | struct input_dev *input = ddata->input; | |
865 | int error = 0; | |
866 | int i; | |
867 | ||
868 | if (device_may_wakeup(dev)) { | |
869 | for (i = 0; i < ddata->pdata->nbuttons; i++) { | |
870 | struct gpio_button_data *bdata = &ddata->data[i]; | |
871 | if (bdata->button->wakeup) | |
872 | disable_irq_wake(bdata->irq); | |
873 | } | |
874 | } else { | |
875 | mutex_lock(&input->mutex); | |
876 | if (input->users) | |
877 | error = gpio_keys_open(input); | |
878 | mutex_unlock(&input->mutex); | |
879 | } | |
880 | ||
881 | if (error) | |
882 | return error; | |
883 | ||
884 | gpio_keys_report_state(ddata); | |
885 | return 0; | |
886 | } | |
887 | ||
888 | static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume); | |
889 | ||
890 | static struct platform_driver gpio_keys_device_driver = { | |
891 | .probe = gpio_keys_probe, | |
892 | .remove = gpio_keys_remove, | |
893 | .driver = { | |
894 | .name = "gpio-keys", | |
895 | .pm = &gpio_keys_pm_ops, | |
896 | .of_match_table = gpio_keys_of_match, | |
897 | } | |
898 | }; | |
899 | ||
900 | static int __init gpio_keys_init(void) | |
901 | { | |
902 | return platform_driver_register(&gpio_keys_device_driver); | |
903 | } | |
904 | ||
905 | static void __exit gpio_keys_exit(void) | |
906 | { | |
907 | platform_driver_unregister(&gpio_keys_device_driver); | |
908 | } | |
909 | ||
910 | late_initcall(gpio_keys_init); | |
911 | module_exit(gpio_keys_exit); | |
912 | ||
913 | MODULE_LICENSE("GPL"); | |
914 | MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>"); | |
915 | MODULE_DESCRIPTION("Keyboard driver for GPIOs"); | |
916 | MODULE_ALIAS("platform:gpio-keys"); |