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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Driver for keys on GPIO lines capable of generating interrupts.
4 *
5 * Copyright 2005 Phil Blundell
6 * Copyright 2010, 2011 David Jander <david@protonic.nl>
7 */
8
9#include <linux/module.h>
10
11#include <linux/init.h>
12#include <linux/fs.h>
13#include <linux/interrupt.h>
14#include <linux/irq.h>
15#include <linux/sched.h>
16#include <linux/pm.h>
17#include <linux/slab.h>
18#include <linux/sysctl.h>
19#include <linux/proc_fs.h>
20#include <linux/delay.h>
21#include <linux/platform_device.h>
22#include <linux/input.h>
23#include <linux/gpio_keys.h>
24#include <linux/workqueue.h>
25#include <linux/gpio.h>
26#include <linux/gpio/consumer.h>
27#include <linux/of.h>
28#include <linux/of_irq.h>
29#include <linux/spinlock.h>
30#include <dt-bindings/input/gpio-keys.h>
31
32struct gpio_button_data {
33 const struct gpio_keys_button *button;
34 struct input_dev *input;
35 struct gpio_desc *gpiod;
36
37 unsigned short *code;
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 unsigned int wakeup_trigger_type;
47 spinlock_t lock;
48 bool disabled;
49 bool key_pressed;
50 bool suspended;
51};
52
53struct gpio_keys_drvdata {
54 const struct gpio_keys_platform_data *pdata;
55 struct input_dev *input;
56 struct mutex disable_lock;
57 unsigned short *keymap;
58 struct gpio_button_data data[];
59};
60
61/*
62 * SYSFS interface for enabling/disabling keys and switches:
63 *
64 * There are 4 attributes under /sys/devices/platform/gpio-keys/
65 * keys [ro] - bitmap of keys (EV_KEY) which can be
66 * disabled
67 * switches [ro] - bitmap of switches (EV_SW) which can be
68 * disabled
69 * disabled_keys [rw] - bitmap of keys currently disabled
70 * disabled_switches [rw] - bitmap of switches currently disabled
71 *
72 * Userland can change these values and hence disable event generation
73 * for each key (or switch). Disabling a key means its interrupt line
74 * is disabled.
75 *
76 * For example, if we have following switches set up as gpio-keys:
77 * SW_DOCK = 5
78 * SW_CAMERA_LENS_COVER = 9
79 * SW_KEYPAD_SLIDE = 10
80 * SW_FRONT_PROXIMITY = 11
81 * This is read from switches:
82 * 11-9,5
83 * Next we want to disable proximity (11) and dock (5), we write:
84 * 11,5
85 * to file disabled_switches. Now proximity and dock IRQs are disabled.
86 * This can be verified by reading the file disabled_switches:
87 * 11,5
88 * If we now want to enable proximity (11) switch we write:
89 * 5
90 * to disabled_switches.
91 *
92 * We can disable only those keys which don't allow sharing the irq.
93 */
94
95/**
96 * get_n_events_by_type() - returns maximum number of events per @type
97 * @type: type of button (%EV_KEY, %EV_SW)
98 *
99 * Return value of this function can be used to allocate bitmap
100 * large enough to hold all bits for given type.
101 */
102static int get_n_events_by_type(int type)
103{
104 BUG_ON(type != EV_SW && type != EV_KEY);
105
106 return (type == EV_KEY) ? KEY_CNT : SW_CNT;
107}
108
109/**
110 * get_bm_events_by_type() - returns bitmap of supported events per @type
111 * @input: input device from which bitmap is retrieved
112 * @type: type of button (%EV_KEY, %EV_SW)
113 *
114 * Return value of this function can be used to allocate bitmap
115 * large enough to hold all bits for given type.
116 */
117static const unsigned long *get_bm_events_by_type(struct input_dev *dev,
118 int type)
119{
120 BUG_ON(type != EV_SW && type != EV_KEY);
121
122 return (type == EV_KEY) ? dev->keybit : dev->swbit;
123}
124
125/**
126 * gpio_keys_disable_button() - disables given GPIO button
127 * @bdata: button data for button to be disabled
128 *
129 * Disables button pointed by @bdata. This is done by masking
130 * IRQ line. After this function is called, button won't generate
131 * input events anymore. Note that one can only disable buttons
132 * that don't share IRQs.
133 *
134 * Make sure that @bdata->disable_lock is locked when entering
135 * this function to avoid races when concurrent threads are
136 * disabling buttons at the same time.
137 */
138static void gpio_keys_disable_button(struct gpio_button_data *bdata)
139{
140 if (!bdata->disabled) {
141 /*
142 * Disable IRQ and associated timer/work structure.
143 */
144 disable_irq(bdata->irq);
145
146 if (bdata->gpiod)
147 cancel_delayed_work_sync(&bdata->work);
148 else
149 del_timer_sync(&bdata->release_timer);
150
151 bdata->disabled = true;
152 }
153}
154
155/**
156 * gpio_keys_enable_button() - enables given GPIO button
157 * @bdata: button data for button to be disabled
158 *
159 * Enables given button pointed by @bdata.
160 *
161 * Make sure that @bdata->disable_lock is locked when entering
162 * this function to avoid races with concurrent threads trying
163 * to enable the same button at the same time.
164 */
165static void gpio_keys_enable_button(struct gpio_button_data *bdata)
166{
167 if (bdata->disabled) {
168 enable_irq(bdata->irq);
169 bdata->disabled = false;
170 }
171}
172
173/**
174 * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons
175 * @ddata: pointer to drvdata
176 * @buf: buffer where stringified bitmap is written
177 * @type: button type (%EV_KEY, %EV_SW)
178 * @only_disabled: does caller want only those buttons that are
179 * currently disabled or all buttons that can be
180 * disabled
181 *
182 * This function writes buttons that can be disabled to @buf. If
183 * @only_disabled is true, then @buf contains only those buttons
184 * that are currently disabled. Returns 0 on success or negative
185 * errno on failure.
186 */
187static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata,
188 char *buf, unsigned int type,
189 bool only_disabled)
190{
191 int n_events = get_n_events_by_type(type);
192 unsigned long *bits;
193 ssize_t ret;
194 int i;
195
196 bits = bitmap_zalloc(n_events, GFP_KERNEL);
197 if (!bits)
198 return -ENOMEM;
199
200 for (i = 0; i < ddata->pdata->nbuttons; i++) {
201 struct gpio_button_data *bdata = &ddata->data[i];
202
203 if (bdata->button->type != type)
204 continue;
205
206 if (only_disabled && !bdata->disabled)
207 continue;
208
209 __set_bit(*bdata->code, bits);
210 }
211
212 ret = scnprintf(buf, PAGE_SIZE - 1, "%*pbl", n_events, bits);
213 buf[ret++] = '\n';
214 buf[ret] = '\0';
215
216 bitmap_free(bits);
217
218 return ret;
219}
220
221/**
222 * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap
223 * @ddata: pointer to drvdata
224 * @buf: buffer from userspace that contains stringified bitmap
225 * @type: button type (%EV_KEY, %EV_SW)
226 *
227 * This function parses stringified bitmap from @buf and disables/enables
228 * GPIO buttons accordingly. Returns 0 on success and negative error
229 * on failure.
230 */
231static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata,
232 const char *buf, unsigned int type)
233{
234 int n_events = get_n_events_by_type(type);
235 const unsigned long *bitmap = get_bm_events_by_type(ddata->input, type);
236 unsigned long *bits;
237 ssize_t error;
238 int i;
239
240 bits = bitmap_zalloc(n_events, GFP_KERNEL);
241 if (!bits)
242 return -ENOMEM;
243
244 error = bitmap_parselist(buf, bits, n_events);
245 if (error)
246 goto out;
247
248 /* First validate */
249 if (!bitmap_subset(bits, bitmap, n_events)) {
250 error = -EINVAL;
251 goto out;
252 }
253
254 for (i = 0; i < ddata->pdata->nbuttons; i++) {
255 struct gpio_button_data *bdata = &ddata->data[i];
256
257 if (bdata->button->type != type)
258 continue;
259
260 if (test_bit(*bdata->code, bits) &&
261 !bdata->button->can_disable) {
262 error = -EINVAL;
263 goto out;
264 }
265 }
266
267 mutex_lock(&ddata->disable_lock);
268
269 for (i = 0; i < ddata->pdata->nbuttons; i++) {
270 struct gpio_button_data *bdata = &ddata->data[i];
271
272 if (bdata->button->type != type)
273 continue;
274
275 if (test_bit(*bdata->code, bits))
276 gpio_keys_disable_button(bdata);
277 else
278 gpio_keys_enable_button(bdata);
279 }
280
281 mutex_unlock(&ddata->disable_lock);
282
283out:
284 bitmap_free(bits);
285 return error;
286}
287
288#define ATTR_SHOW_FN(name, type, only_disabled) \
289static ssize_t gpio_keys_show_##name(struct device *dev, \
290 struct device_attribute *attr, \
291 char *buf) \
292{ \
293 struct platform_device *pdev = to_platform_device(dev); \
294 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \
295 \
296 return gpio_keys_attr_show_helper(ddata, buf, \
297 type, only_disabled); \
298}
299
300ATTR_SHOW_FN(keys, EV_KEY, false);
301ATTR_SHOW_FN(switches, EV_SW, false);
302ATTR_SHOW_FN(disabled_keys, EV_KEY, true);
303ATTR_SHOW_FN(disabled_switches, EV_SW, true);
304
305/*
306 * ATTRIBUTES:
307 *
308 * /sys/devices/platform/gpio-keys/keys [ro]
309 * /sys/devices/platform/gpio-keys/switches [ro]
310 */
311static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL);
312static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL);
313
314#define ATTR_STORE_FN(name, type) \
315static ssize_t gpio_keys_store_##name(struct device *dev, \
316 struct device_attribute *attr, \
317 const char *buf, \
318 size_t count) \
319{ \
320 struct platform_device *pdev = to_platform_device(dev); \
321 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \
322 ssize_t error; \
323 \
324 error = gpio_keys_attr_store_helper(ddata, buf, type); \
325 if (error) \
326 return error; \
327 \
328 return count; \
329}
330
331ATTR_STORE_FN(disabled_keys, EV_KEY);
332ATTR_STORE_FN(disabled_switches, EV_SW);
333
334/*
335 * ATTRIBUTES:
336 *
337 * /sys/devices/platform/gpio-keys/disabled_keys [rw]
338 * /sys/devices/platform/gpio-keys/disables_switches [rw]
339 */
340static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO,
341 gpio_keys_show_disabled_keys,
342 gpio_keys_store_disabled_keys);
343static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO,
344 gpio_keys_show_disabled_switches,
345 gpio_keys_store_disabled_switches);
346
347static struct attribute *gpio_keys_attrs[] = {
348 &dev_attr_keys.attr,
349 &dev_attr_switches.attr,
350 &dev_attr_disabled_keys.attr,
351 &dev_attr_disabled_switches.attr,
352 NULL,
353};
354ATTRIBUTE_GROUPS(gpio_keys);
355
356static 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, *bdata->code, state);
375 }
376 input_sync(input);
377}
378
379static 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
390static 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 const struct gpio_keys_button *button = bdata->button;
398
399 pm_stay_awake(bdata->input->dev.parent);
400 if (bdata->suspended &&
401 (button->type == 0 || button->type == EV_KEY)) {
402 /*
403 * Simulate wakeup key press in case the key has
404 * already released by the time we got interrupt
405 * handler to run.
406 */
407 input_report_key(bdata->input, button->code, 1);
408 }
409 }
410
411 mod_delayed_work(system_wq,
412 &bdata->work,
413 msecs_to_jiffies(bdata->software_debounce));
414
415 return IRQ_HANDLED;
416}
417
418static void gpio_keys_irq_timer(struct timer_list *t)
419{
420 struct gpio_button_data *bdata = from_timer(bdata, t, release_timer);
421 struct input_dev *input = bdata->input;
422 unsigned long flags;
423
424 spin_lock_irqsave(&bdata->lock, flags);
425 if (bdata->key_pressed) {
426 input_event(input, EV_KEY, *bdata->code, 0);
427 input_sync(input);
428 bdata->key_pressed = false;
429 }
430 spin_unlock_irqrestore(&bdata->lock, flags);
431}
432
433static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id)
434{
435 struct gpio_button_data *bdata = dev_id;
436 struct input_dev *input = bdata->input;
437 unsigned long flags;
438
439 BUG_ON(irq != bdata->irq);
440
441 spin_lock_irqsave(&bdata->lock, flags);
442
443 if (!bdata->key_pressed) {
444 if (bdata->button->wakeup)
445 pm_wakeup_event(bdata->input->dev.parent, 0);
446
447 input_event(input, EV_KEY, *bdata->code, 1);
448 input_sync(input);
449
450 if (!bdata->release_delay) {
451 input_event(input, EV_KEY, *bdata->code, 0);
452 input_sync(input);
453 goto out;
454 }
455
456 bdata->key_pressed = true;
457 }
458
459 if (bdata->release_delay)
460 mod_timer(&bdata->release_timer,
461 jiffies + msecs_to_jiffies(bdata->release_delay));
462out:
463 spin_unlock_irqrestore(&bdata->lock, flags);
464 return IRQ_HANDLED;
465}
466
467static void gpio_keys_quiesce_key(void *data)
468{
469 struct gpio_button_data *bdata = data;
470
471 if (bdata->gpiod)
472 cancel_delayed_work_sync(&bdata->work);
473 else
474 del_timer_sync(&bdata->release_timer);
475}
476
477static int gpio_keys_setup_key(struct platform_device *pdev,
478 struct input_dev *input,
479 struct gpio_keys_drvdata *ddata,
480 const struct gpio_keys_button *button,
481 int idx,
482 struct fwnode_handle *child)
483{
484 const char *desc = button->desc ? button->desc : "gpio_keys";
485 struct device *dev = &pdev->dev;
486 struct gpio_button_data *bdata = &ddata->data[idx];
487 irq_handler_t isr;
488 unsigned long irqflags;
489 int irq;
490 int error;
491
492 bdata->input = input;
493 bdata->button = button;
494 spin_lock_init(&bdata->lock);
495
496 if (child) {
497 bdata->gpiod = devm_fwnode_gpiod_get(dev, child,
498 NULL, GPIOD_IN, desc);
499 if (IS_ERR(bdata->gpiod)) {
500 error = PTR_ERR(bdata->gpiod);
501 if (error == -ENOENT) {
502 /*
503 * GPIO is optional, we may be dealing with
504 * purely interrupt-driven setup.
505 */
506 bdata->gpiod = NULL;
507 } else {
508 if (error != -EPROBE_DEFER)
509 dev_err(dev, "failed to get gpio: %d\n",
510 error);
511 return error;
512 }
513 }
514 } else if (gpio_is_valid(button->gpio)) {
515 /*
516 * Legacy GPIO number, so request the GPIO here and
517 * convert it to descriptor.
518 */
519 unsigned flags = GPIOF_IN;
520
521 if (button->active_low)
522 flags |= GPIOF_ACTIVE_LOW;
523
524 error = devm_gpio_request_one(dev, button->gpio, flags, desc);
525 if (error < 0) {
526 dev_err(dev, "Failed to request GPIO %d, error %d\n",
527 button->gpio, error);
528 return error;
529 }
530
531 bdata->gpiod = gpio_to_desc(button->gpio);
532 if (!bdata->gpiod)
533 return -EINVAL;
534 }
535
536 if (bdata->gpiod) {
537 bool active_low = gpiod_is_active_low(bdata->gpiod);
538
539 if (button->debounce_interval) {
540 error = gpiod_set_debounce(bdata->gpiod,
541 button->debounce_interval * 1000);
542 /* use timer if gpiolib doesn't provide debounce */
543 if (error < 0)
544 bdata->software_debounce =
545 button->debounce_interval;
546 }
547
548 if (button->irq) {
549 bdata->irq = button->irq;
550 } else {
551 irq = gpiod_to_irq(bdata->gpiod);
552 if (irq < 0) {
553 error = irq;
554 dev_err(dev,
555 "Unable to get irq number for GPIO %d, error %d\n",
556 button->gpio, error);
557 return error;
558 }
559 bdata->irq = irq;
560 }
561
562 INIT_DELAYED_WORK(&bdata->work, gpio_keys_gpio_work_func);
563
564 isr = gpio_keys_gpio_isr;
565 irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
566
567 switch (button->wakeup_event_action) {
568 case EV_ACT_ASSERTED:
569 bdata->wakeup_trigger_type = active_low ?
570 IRQ_TYPE_EDGE_FALLING : IRQ_TYPE_EDGE_RISING;
571 break;
572 case EV_ACT_DEASSERTED:
573 bdata->wakeup_trigger_type = active_low ?
574 IRQ_TYPE_EDGE_RISING : IRQ_TYPE_EDGE_FALLING;
575 break;
576 case EV_ACT_ANY:
577 default:
578 /*
579 * For other cases, we are OK letting suspend/resume
580 * not reconfigure the trigger type.
581 */
582 break;
583 }
584 } else {
585 if (!button->irq) {
586 dev_err(dev, "Found button without gpio or irq\n");
587 return -EINVAL;
588 }
589
590 bdata->irq = button->irq;
591
592 if (button->type && button->type != EV_KEY) {
593 dev_err(dev, "Only EV_KEY allowed for IRQ buttons.\n");
594 return -EINVAL;
595 }
596
597 bdata->release_delay = button->debounce_interval;
598 timer_setup(&bdata->release_timer, gpio_keys_irq_timer, 0);
599
600 isr = gpio_keys_irq_isr;
601 irqflags = 0;
602
603 /*
604 * For IRQ buttons, there is no interrupt for release.
605 * So we don't need to reconfigure the trigger type for wakeup.
606 */
607 }
608
609 bdata->code = &ddata->keymap[idx];
610 *bdata->code = button->code;
611 input_set_capability(input, button->type ?: EV_KEY, *bdata->code);
612
613 /*
614 * Install custom action to cancel release timer and
615 * workqueue item.
616 */
617 error = devm_add_action(dev, gpio_keys_quiesce_key, bdata);
618 if (error) {
619 dev_err(dev, "failed to register quiesce action, error: %d\n",
620 error);
621 return error;
622 }
623
624 /*
625 * If platform has specified that the button can be disabled,
626 * we don't want it to share the interrupt line.
627 */
628 if (!button->can_disable)
629 irqflags |= IRQF_SHARED;
630
631 error = devm_request_any_context_irq(dev, bdata->irq, isr, irqflags,
632 desc, bdata);
633 if (error < 0) {
634 dev_err(dev, "Unable to claim irq %d; error %d\n",
635 bdata->irq, error);
636 return error;
637 }
638
639 return 0;
640}
641
642static void gpio_keys_report_state(struct gpio_keys_drvdata *ddata)
643{
644 struct input_dev *input = ddata->input;
645 int i;
646
647 for (i = 0; i < ddata->pdata->nbuttons; i++) {
648 struct gpio_button_data *bdata = &ddata->data[i];
649 if (bdata->gpiod)
650 gpio_keys_gpio_report_event(bdata);
651 }
652 input_sync(input);
653}
654
655static int gpio_keys_open(struct input_dev *input)
656{
657 struct gpio_keys_drvdata *ddata = input_get_drvdata(input);
658 const struct gpio_keys_platform_data *pdata = ddata->pdata;
659 int error;
660
661 if (pdata->enable) {
662 error = pdata->enable(input->dev.parent);
663 if (error)
664 return error;
665 }
666
667 /* Report current state of buttons that are connected to GPIOs */
668 gpio_keys_report_state(ddata);
669
670 return 0;
671}
672
673static void gpio_keys_close(struct input_dev *input)
674{
675 struct gpio_keys_drvdata *ddata = input_get_drvdata(input);
676 const struct gpio_keys_platform_data *pdata = ddata->pdata;
677
678 if (pdata->disable)
679 pdata->disable(input->dev.parent);
680}
681
682/*
683 * Handlers for alternative sources of platform_data
684 */
685
686/*
687 * Translate properties into platform_data
688 */
689static struct gpio_keys_platform_data *
690gpio_keys_get_devtree_pdata(struct device *dev)
691{
692 struct gpio_keys_platform_data *pdata;
693 struct gpio_keys_button *button;
694 struct fwnode_handle *child;
695 int nbuttons;
696
697 nbuttons = device_get_child_node_count(dev);
698 if (nbuttons == 0)
699 return ERR_PTR(-ENODEV);
700
701 pdata = devm_kzalloc(dev,
702 sizeof(*pdata) + nbuttons * sizeof(*button),
703 GFP_KERNEL);
704 if (!pdata)
705 return ERR_PTR(-ENOMEM);
706
707 button = (struct gpio_keys_button *)(pdata + 1);
708
709 pdata->buttons = button;
710 pdata->nbuttons = nbuttons;
711
712 pdata->rep = device_property_read_bool(dev, "autorepeat");
713
714 device_property_read_string(dev, "label", &pdata->name);
715
716 device_for_each_child_node(dev, child) {
717 if (is_of_node(child))
718 button->irq =
719 irq_of_parse_and_map(to_of_node(child), 0);
720
721 if (fwnode_property_read_u32(child, "linux,code",
722 &button->code)) {
723 dev_err(dev, "Button without keycode\n");
724 fwnode_handle_put(child);
725 return ERR_PTR(-EINVAL);
726 }
727
728 fwnode_property_read_string(child, "label", &button->desc);
729
730 if (fwnode_property_read_u32(child, "linux,input-type",
731 &button->type))
732 button->type = EV_KEY;
733
734 button->wakeup =
735 fwnode_property_read_bool(child, "wakeup-source") ||
736 /* legacy name */
737 fwnode_property_read_bool(child, "gpio-key,wakeup");
738
739 fwnode_property_read_u32(child, "wakeup-event-action",
740 &button->wakeup_event_action);
741
742 button->can_disable =
743 fwnode_property_read_bool(child, "linux,can-disable");
744
745 if (fwnode_property_read_u32(child, "debounce-interval",
746 &button->debounce_interval))
747 button->debounce_interval = 5;
748
749 button++;
750 }
751
752 return pdata;
753}
754
755static const struct of_device_id gpio_keys_of_match[] = {
756 { .compatible = "gpio-keys", },
757 { },
758};
759MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
760
761static int gpio_keys_probe(struct platform_device *pdev)
762{
763 struct device *dev = &pdev->dev;
764 const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev);
765 struct fwnode_handle *child = NULL;
766 struct gpio_keys_drvdata *ddata;
767 struct input_dev *input;
768 int i, error;
769 int wakeup = 0;
770
771 if (!pdata) {
772 pdata = gpio_keys_get_devtree_pdata(dev);
773 if (IS_ERR(pdata))
774 return PTR_ERR(pdata);
775 }
776
777 ddata = devm_kzalloc(dev, struct_size(ddata, data, pdata->nbuttons),
778 GFP_KERNEL);
779 if (!ddata) {
780 dev_err(dev, "failed to allocate state\n");
781 return -ENOMEM;
782 }
783
784 ddata->keymap = devm_kcalloc(dev,
785 pdata->nbuttons, sizeof(ddata->keymap[0]),
786 GFP_KERNEL);
787 if (!ddata->keymap)
788 return -ENOMEM;
789
790 input = devm_input_allocate_device(dev);
791 if (!input) {
792 dev_err(dev, "failed to allocate input device\n");
793 return -ENOMEM;
794 }
795
796 ddata->pdata = pdata;
797 ddata->input = input;
798 mutex_init(&ddata->disable_lock);
799
800 platform_set_drvdata(pdev, ddata);
801 input_set_drvdata(input, ddata);
802
803 input->name = pdata->name ? : pdev->name;
804 input->phys = "gpio-keys/input0";
805 input->dev.parent = dev;
806 input->open = gpio_keys_open;
807 input->close = gpio_keys_close;
808
809 input->id.bustype = BUS_HOST;
810 input->id.vendor = 0x0001;
811 input->id.product = 0x0001;
812 input->id.version = 0x0100;
813
814 input->keycode = ddata->keymap;
815 input->keycodesize = sizeof(ddata->keymap[0]);
816 input->keycodemax = pdata->nbuttons;
817
818 /* Enable auto repeat feature of Linux input subsystem */
819 if (pdata->rep)
820 __set_bit(EV_REP, input->evbit);
821
822 for (i = 0; i < pdata->nbuttons; i++) {
823 const struct gpio_keys_button *button = &pdata->buttons[i];
824
825 if (!dev_get_platdata(dev)) {
826 child = device_get_next_child_node(dev, child);
827 if (!child) {
828 dev_err(dev,
829 "missing child device node for entry %d\n",
830 i);
831 return -EINVAL;
832 }
833 }
834
835 error = gpio_keys_setup_key(pdev, input, ddata,
836 button, i, child);
837 if (error) {
838 fwnode_handle_put(child);
839 return error;
840 }
841
842 if (button->wakeup)
843 wakeup = 1;
844 }
845
846 fwnode_handle_put(child);
847
848 error = input_register_device(input);
849 if (error) {
850 dev_err(dev, "Unable to register input device, error: %d\n",
851 error);
852 return error;
853 }
854
855 device_init_wakeup(dev, wakeup);
856
857 return 0;
858}
859
860static int __maybe_unused
861gpio_keys_button_enable_wakeup(struct gpio_button_data *bdata)
862{
863 int error;
864
865 error = enable_irq_wake(bdata->irq);
866 if (error) {
867 dev_err(bdata->input->dev.parent,
868 "failed to configure IRQ %d as wakeup source: %d\n",
869 bdata->irq, error);
870 return error;
871 }
872
873 if (bdata->wakeup_trigger_type) {
874 error = irq_set_irq_type(bdata->irq,
875 bdata->wakeup_trigger_type);
876 if (error) {
877 dev_err(bdata->input->dev.parent,
878 "failed to set wakeup trigger %08x for IRQ %d: %d\n",
879 bdata->wakeup_trigger_type, bdata->irq, error);
880 disable_irq_wake(bdata->irq);
881 return error;
882 }
883 }
884
885 return 0;
886}
887
888static void __maybe_unused
889gpio_keys_button_disable_wakeup(struct gpio_button_data *bdata)
890{
891 int error;
892
893 /*
894 * The trigger type is always both edges for gpio-based keys and we do
895 * not support changing wakeup trigger for interrupt-based keys.
896 */
897 if (bdata->wakeup_trigger_type) {
898 error = irq_set_irq_type(bdata->irq, IRQ_TYPE_EDGE_BOTH);
899 if (error)
900 dev_warn(bdata->input->dev.parent,
901 "failed to restore interrupt trigger for IRQ %d: %d\n",
902 bdata->irq, error);
903 }
904
905 error = disable_irq_wake(bdata->irq);
906 if (error)
907 dev_warn(bdata->input->dev.parent,
908 "failed to disable IRQ %d as wake source: %d\n",
909 bdata->irq, error);
910}
911
912static int __maybe_unused
913gpio_keys_enable_wakeup(struct gpio_keys_drvdata *ddata)
914{
915 struct gpio_button_data *bdata;
916 int error;
917 int i;
918
919 for (i = 0; i < ddata->pdata->nbuttons; i++) {
920 bdata = &ddata->data[i];
921 if (bdata->button->wakeup) {
922 error = gpio_keys_button_enable_wakeup(bdata);
923 if (error)
924 goto err_out;
925 }
926 bdata->suspended = true;
927 }
928
929 return 0;
930
931err_out:
932 while (i--) {
933 bdata = &ddata->data[i];
934 if (bdata->button->wakeup)
935 gpio_keys_button_disable_wakeup(bdata);
936 bdata->suspended = false;
937 }
938
939 return error;
940}
941
942static void __maybe_unused
943gpio_keys_disable_wakeup(struct gpio_keys_drvdata *ddata)
944{
945 struct gpio_button_data *bdata;
946 int i;
947
948 for (i = 0; i < ddata->pdata->nbuttons; i++) {
949 bdata = &ddata->data[i];
950 bdata->suspended = false;
951 if (irqd_is_wakeup_set(irq_get_irq_data(bdata->irq)))
952 gpio_keys_button_disable_wakeup(bdata);
953 }
954}
955
956static int __maybe_unused gpio_keys_suspend(struct device *dev)
957{
958 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev);
959 struct input_dev *input = ddata->input;
960 int error;
961
962 if (device_may_wakeup(dev)) {
963 error = gpio_keys_enable_wakeup(ddata);
964 if (error)
965 return error;
966 } else {
967 mutex_lock(&input->mutex);
968 if (input->users)
969 gpio_keys_close(input);
970 mutex_unlock(&input->mutex);
971 }
972
973 return 0;
974}
975
976static int __maybe_unused gpio_keys_resume(struct device *dev)
977{
978 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev);
979 struct input_dev *input = ddata->input;
980 int error = 0;
981
982 if (device_may_wakeup(dev)) {
983 gpio_keys_disable_wakeup(ddata);
984 } else {
985 mutex_lock(&input->mutex);
986 if (input->users)
987 error = gpio_keys_open(input);
988 mutex_unlock(&input->mutex);
989 }
990
991 if (error)
992 return error;
993
994 gpio_keys_report_state(ddata);
995 return 0;
996}
997
998static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume);
999
1000static void gpio_keys_shutdown(struct platform_device *pdev)
1001{
1002 int ret;
1003
1004 ret = gpio_keys_suspend(&pdev->dev);
1005 if (ret)
1006 dev_err(&pdev->dev, "failed to shutdown\n");
1007}
1008
1009static struct platform_driver gpio_keys_device_driver = {
1010 .probe = gpio_keys_probe,
1011 .shutdown = gpio_keys_shutdown,
1012 .driver = {
1013 .name = "gpio-keys",
1014 .pm = &gpio_keys_pm_ops,
1015 .of_match_table = gpio_keys_of_match,
1016 .dev_groups = gpio_keys_groups,
1017 }
1018};
1019
1020static int __init gpio_keys_init(void)
1021{
1022 return platform_driver_register(&gpio_keys_device_driver);
1023}
1024
1025static void __exit gpio_keys_exit(void)
1026{
1027 platform_driver_unregister(&gpio_keys_device_driver);
1028}
1029
1030late_initcall(gpio_keys_init);
1031module_exit(gpio_keys_exit);
1032
1033MODULE_LICENSE("GPL");
1034MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>");
1035MODULE_DESCRIPTION("Keyboard driver for GPIOs");
1036MODULE_ALIAS("platform:gpio-keys");
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/of_platform.h>
30#include <linux/of_gpio.h>
31
32struct gpio_button_data {
33 struct gpio_keys_button *button;
34 struct input_dev *input;
35 struct timer_list timer;
36 struct work_struct work;
37 int timer_debounce; /* in msecs */
38 bool disabled;
39};
40
41struct gpio_keys_drvdata {
42 struct input_dev *input;
43 struct mutex disable_lock;
44 unsigned int n_buttons;
45 int (*enable)(struct device *dev);
46 void (*disable)(struct device *dev);
47 struct gpio_button_data data[0];
48};
49
50/*
51 * SYSFS interface for enabling/disabling keys and switches:
52 *
53 * There are 4 attributes under /sys/devices/platform/gpio-keys/
54 * keys [ro] - bitmap of keys (EV_KEY) which can be
55 * disabled
56 * switches [ro] - bitmap of switches (EV_SW) which can be
57 * disabled
58 * disabled_keys [rw] - bitmap of keys currently disabled
59 * disabled_switches [rw] - bitmap of switches currently disabled
60 *
61 * Userland can change these values and hence disable event generation
62 * for each key (or switch). Disabling a key means its interrupt line
63 * is disabled.
64 *
65 * For example, if we have following switches set up as gpio-keys:
66 * SW_DOCK = 5
67 * SW_CAMERA_LENS_COVER = 9
68 * SW_KEYPAD_SLIDE = 10
69 * SW_FRONT_PROXIMITY = 11
70 * This is read from switches:
71 * 11-9,5
72 * Next we want to disable proximity (11) and dock (5), we write:
73 * 11,5
74 * to file disabled_switches. Now proximity and dock IRQs are disabled.
75 * This can be verified by reading the file disabled_switches:
76 * 11,5
77 * If we now want to enable proximity (11) switch we write:
78 * 5
79 * to disabled_switches.
80 *
81 * We can disable only those keys which don't allow sharing the irq.
82 */
83
84/**
85 * get_n_events_by_type() - returns maximum number of events per @type
86 * @type: type of button (%EV_KEY, %EV_SW)
87 *
88 * Return value of this function can be used to allocate bitmap
89 * large enough to hold all bits for given type.
90 */
91static inline int get_n_events_by_type(int type)
92{
93 BUG_ON(type != EV_SW && type != EV_KEY);
94
95 return (type == EV_KEY) ? KEY_CNT : SW_CNT;
96}
97
98/**
99 * gpio_keys_disable_button() - disables given GPIO button
100 * @bdata: button data for button to be disabled
101 *
102 * Disables button pointed by @bdata. This is done by masking
103 * IRQ line. After this function is called, button won't generate
104 * input events anymore. Note that one can only disable buttons
105 * that don't share IRQs.
106 *
107 * Make sure that @bdata->disable_lock is locked when entering
108 * this function to avoid races when concurrent threads are
109 * disabling buttons at the same time.
110 */
111static void gpio_keys_disable_button(struct gpio_button_data *bdata)
112{
113 if (!bdata->disabled) {
114 /*
115 * Disable IRQ and possible debouncing timer.
116 */
117 disable_irq(gpio_to_irq(bdata->button->gpio));
118 if (bdata->timer_debounce)
119 del_timer_sync(&bdata->timer);
120
121 bdata->disabled = true;
122 }
123}
124
125/**
126 * gpio_keys_enable_button() - enables given GPIO button
127 * @bdata: button data for button to be disabled
128 *
129 * Enables given button pointed by @bdata.
130 *
131 * Make sure that @bdata->disable_lock is locked when entering
132 * this function to avoid races with concurrent threads trying
133 * to enable the same button at the same time.
134 */
135static void gpio_keys_enable_button(struct gpio_button_data *bdata)
136{
137 if (bdata->disabled) {
138 enable_irq(gpio_to_irq(bdata->button->gpio));
139 bdata->disabled = false;
140 }
141}
142
143/**
144 * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons
145 * @ddata: pointer to drvdata
146 * @buf: buffer where stringified bitmap is written
147 * @type: button type (%EV_KEY, %EV_SW)
148 * @only_disabled: does caller want only those buttons that are
149 * currently disabled or all buttons that can be
150 * disabled
151 *
152 * This function writes buttons that can be disabled to @buf. If
153 * @only_disabled is true, then @buf contains only those buttons
154 * that are currently disabled. Returns 0 on success or negative
155 * errno on failure.
156 */
157static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata,
158 char *buf, unsigned int type,
159 bool only_disabled)
160{
161 int n_events = get_n_events_by_type(type);
162 unsigned long *bits;
163 ssize_t ret;
164 int i;
165
166 bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
167 if (!bits)
168 return -ENOMEM;
169
170 for (i = 0; i < ddata->n_buttons; i++) {
171 struct gpio_button_data *bdata = &ddata->data[i];
172
173 if (bdata->button->type != type)
174 continue;
175
176 if (only_disabled && !bdata->disabled)
177 continue;
178
179 __set_bit(bdata->button->code, bits);
180 }
181
182 ret = bitmap_scnlistprintf(buf, PAGE_SIZE - 2, bits, n_events);
183 buf[ret++] = '\n';
184 buf[ret] = '\0';
185
186 kfree(bits);
187
188 return ret;
189}
190
191/**
192 * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap
193 * @ddata: pointer to drvdata
194 * @buf: buffer from userspace that contains stringified bitmap
195 * @type: button type (%EV_KEY, %EV_SW)
196 *
197 * This function parses stringified bitmap from @buf and disables/enables
198 * GPIO buttons accordinly. Returns 0 on success and negative error
199 * on failure.
200 */
201static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata,
202 const char *buf, unsigned int type)
203{
204 int n_events = get_n_events_by_type(type);
205 unsigned long *bits;
206 ssize_t error;
207 int i;
208
209 bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
210 if (!bits)
211 return -ENOMEM;
212
213 error = bitmap_parselist(buf, bits, n_events);
214 if (error)
215 goto out;
216
217 /* First validate */
218 for (i = 0; i < ddata->n_buttons; i++) {
219 struct gpio_button_data *bdata = &ddata->data[i];
220
221 if (bdata->button->type != type)
222 continue;
223
224 if (test_bit(bdata->button->code, bits) &&
225 !bdata->button->can_disable) {
226 error = -EINVAL;
227 goto out;
228 }
229 }
230
231 mutex_lock(&ddata->disable_lock);
232
233 for (i = 0; i < ddata->n_buttons; i++) {
234 struct gpio_button_data *bdata = &ddata->data[i];
235
236 if (bdata->button->type != type)
237 continue;
238
239 if (test_bit(bdata->button->code, bits))
240 gpio_keys_disable_button(bdata);
241 else
242 gpio_keys_enable_button(bdata);
243 }
244
245 mutex_unlock(&ddata->disable_lock);
246
247out:
248 kfree(bits);
249 return error;
250}
251
252#define ATTR_SHOW_FN(name, type, only_disabled) \
253static ssize_t gpio_keys_show_##name(struct device *dev, \
254 struct device_attribute *attr, \
255 char *buf) \
256{ \
257 struct platform_device *pdev = to_platform_device(dev); \
258 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \
259 \
260 return gpio_keys_attr_show_helper(ddata, buf, \
261 type, only_disabled); \
262}
263
264ATTR_SHOW_FN(keys, EV_KEY, false);
265ATTR_SHOW_FN(switches, EV_SW, false);
266ATTR_SHOW_FN(disabled_keys, EV_KEY, true);
267ATTR_SHOW_FN(disabled_switches, EV_SW, true);
268
269/*
270 * ATTRIBUTES:
271 *
272 * /sys/devices/platform/gpio-keys/keys [ro]
273 * /sys/devices/platform/gpio-keys/switches [ro]
274 */
275static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL);
276static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL);
277
278#define ATTR_STORE_FN(name, type) \
279static ssize_t gpio_keys_store_##name(struct device *dev, \
280 struct device_attribute *attr, \
281 const char *buf, \
282 size_t count) \
283{ \
284 struct platform_device *pdev = to_platform_device(dev); \
285 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \
286 ssize_t error; \
287 \
288 error = gpio_keys_attr_store_helper(ddata, buf, type); \
289 if (error) \
290 return error; \
291 \
292 return count; \
293}
294
295ATTR_STORE_FN(disabled_keys, EV_KEY);
296ATTR_STORE_FN(disabled_switches, EV_SW);
297
298/*
299 * ATTRIBUTES:
300 *
301 * /sys/devices/platform/gpio-keys/disabled_keys [rw]
302 * /sys/devices/platform/gpio-keys/disables_switches [rw]
303 */
304static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO,
305 gpio_keys_show_disabled_keys,
306 gpio_keys_store_disabled_keys);
307static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO,
308 gpio_keys_show_disabled_switches,
309 gpio_keys_store_disabled_switches);
310
311static struct attribute *gpio_keys_attrs[] = {
312 &dev_attr_keys.attr,
313 &dev_attr_switches.attr,
314 &dev_attr_disabled_keys.attr,
315 &dev_attr_disabled_switches.attr,
316 NULL,
317};
318
319static struct attribute_group gpio_keys_attr_group = {
320 .attrs = gpio_keys_attrs,
321};
322
323static void gpio_keys_report_event(struct gpio_button_data *bdata)
324{
325 struct gpio_keys_button *button = bdata->button;
326 struct input_dev *input = bdata->input;
327 unsigned int type = button->type ?: EV_KEY;
328 int state = (gpio_get_value_cansleep(button->gpio) ? 1 : 0) ^ button->active_low;
329
330 if (type == EV_ABS) {
331 if (state)
332 input_event(input, type, button->code, button->value);
333 } else {
334 input_event(input, type, button->code, !!state);
335 }
336 input_sync(input);
337}
338
339static void gpio_keys_work_func(struct work_struct *work)
340{
341 struct gpio_button_data *bdata =
342 container_of(work, struct gpio_button_data, work);
343
344 gpio_keys_report_event(bdata);
345}
346
347static void gpio_keys_timer(unsigned long _data)
348{
349 struct gpio_button_data *data = (struct gpio_button_data *)_data;
350
351 schedule_work(&data->work);
352}
353
354static irqreturn_t gpio_keys_isr(int irq, void *dev_id)
355{
356 struct gpio_button_data *bdata = dev_id;
357 struct gpio_keys_button *button = bdata->button;
358
359 BUG_ON(irq != gpio_to_irq(button->gpio));
360
361 if (bdata->timer_debounce)
362 mod_timer(&bdata->timer,
363 jiffies + msecs_to_jiffies(bdata->timer_debounce));
364 else
365 schedule_work(&bdata->work);
366
367 return IRQ_HANDLED;
368}
369
370static int __devinit gpio_keys_setup_key(struct platform_device *pdev,
371 struct gpio_button_data *bdata,
372 struct gpio_keys_button *button)
373{
374 const char *desc = button->desc ? button->desc : "gpio_keys";
375 struct device *dev = &pdev->dev;
376 unsigned long irqflags;
377 int irq, error;
378
379 setup_timer(&bdata->timer, gpio_keys_timer, (unsigned long)bdata);
380 INIT_WORK(&bdata->work, gpio_keys_work_func);
381
382 error = gpio_request(button->gpio, desc);
383 if (error < 0) {
384 dev_err(dev, "failed to request GPIO %d, error %d\n",
385 button->gpio, error);
386 goto fail2;
387 }
388
389 error = gpio_direction_input(button->gpio);
390 if (error < 0) {
391 dev_err(dev, "failed to configure"
392 " direction for GPIO %d, error %d\n",
393 button->gpio, error);
394 goto fail3;
395 }
396
397 if (button->debounce_interval) {
398 error = gpio_set_debounce(button->gpio,
399 button->debounce_interval * 1000);
400 /* use timer if gpiolib doesn't provide debounce */
401 if (error < 0)
402 bdata->timer_debounce = button->debounce_interval;
403 }
404
405 irq = gpio_to_irq(button->gpio);
406 if (irq < 0) {
407 error = irq;
408 dev_err(dev, "Unable to get irq number for GPIO %d, error %d\n",
409 button->gpio, error);
410 goto fail3;
411 }
412
413 irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
414 /*
415 * If platform has specified that the button can be disabled,
416 * we don't want it to share the interrupt line.
417 */
418 if (!button->can_disable)
419 irqflags |= IRQF_SHARED;
420
421 error = request_threaded_irq(irq, NULL, gpio_keys_isr, irqflags, desc, bdata);
422 if (error < 0) {
423 dev_err(dev, "Unable to claim irq %d; error %d\n",
424 irq, error);
425 goto fail3;
426 }
427
428 return 0;
429
430fail3:
431 gpio_free(button->gpio);
432fail2:
433 return error;
434}
435
436static int gpio_keys_open(struct input_dev *input)
437{
438 struct gpio_keys_drvdata *ddata = input_get_drvdata(input);
439
440 return ddata->enable ? ddata->enable(input->dev.parent) : 0;
441}
442
443static void gpio_keys_close(struct input_dev *input)
444{
445 struct gpio_keys_drvdata *ddata = input_get_drvdata(input);
446
447 if (ddata->disable)
448 ddata->disable(input->dev.parent);
449}
450
451/*
452 * Handlers for alternative sources of platform_data
453 */
454#ifdef CONFIG_OF
455/*
456 * Translate OpenFirmware node properties into platform_data
457 */
458static int gpio_keys_get_devtree_pdata(struct device *dev,
459 struct gpio_keys_platform_data *pdata)
460{
461 struct device_node *node, *pp;
462 int i;
463 struct gpio_keys_button *buttons;
464 const u32 *reg;
465 int len;
466
467 node = dev->of_node;
468 if (node == NULL)
469 return -ENODEV;
470
471 memset(pdata, 0, sizeof *pdata);
472
473 pdata->rep = !!of_get_property(node, "autorepeat", &len);
474
475 /* First count the subnodes */
476 pdata->nbuttons = 0;
477 pp = NULL;
478 while ((pp = of_get_next_child(node, pp)))
479 pdata->nbuttons++;
480
481 if (pdata->nbuttons == 0)
482 return -ENODEV;
483
484 buttons = kzalloc(pdata->nbuttons * (sizeof *buttons), GFP_KERNEL);
485 if (!buttons)
486 return -ENOMEM;
487
488 pp = NULL;
489 i = 0;
490 while ((pp = of_get_next_child(node, pp))) {
491 enum of_gpio_flags flags;
492
493 if (!of_find_property(pp, "gpios", NULL)) {
494 pdata->nbuttons--;
495 dev_warn(dev, "Found button without gpios\n");
496 continue;
497 }
498 buttons[i].gpio = of_get_gpio_flags(pp, 0, &flags);
499 buttons[i].active_low = flags & OF_GPIO_ACTIVE_LOW;
500
501 reg = of_get_property(pp, "linux,code", &len);
502 if (!reg) {
503 dev_err(dev, "Button without keycode: 0x%x\n", buttons[i].gpio);
504 goto out_fail;
505 }
506 buttons[i].code = be32_to_cpup(reg);
507
508 buttons[i].desc = of_get_property(pp, "label", &len);
509
510 reg = of_get_property(pp, "linux,input-type", &len);
511 buttons[i].type = reg ? be32_to_cpup(reg) : EV_KEY;
512
513 buttons[i].wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL);
514
515 reg = of_get_property(pp, "debounce-interval", &len);
516 buttons[i].debounce_interval = reg ? be32_to_cpup(reg) : 5;
517
518 i++;
519 }
520
521 pdata->buttons = buttons;
522
523 return 0;
524
525out_fail:
526 kfree(buttons);
527 return -ENODEV;
528}
529
530static struct of_device_id gpio_keys_of_match[] = {
531 { .compatible = "gpio-keys", },
532 { },
533};
534MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
535
536#else
537
538static int gpio_keys_get_devtree_pdata(struct device *dev,
539 struct gpio_keys_platform_data *altp)
540{
541 return -ENODEV;
542}
543
544#define gpio_keys_of_match NULL
545
546#endif
547
548static int __devinit gpio_keys_probe(struct platform_device *pdev)
549{
550 struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
551 struct gpio_keys_drvdata *ddata;
552 struct device *dev = &pdev->dev;
553 struct gpio_keys_platform_data alt_pdata;
554 struct input_dev *input;
555 int i, error;
556 int wakeup = 0;
557
558 if (!pdata) {
559 error = gpio_keys_get_devtree_pdata(dev, &alt_pdata);
560 if (error)
561 return error;
562 pdata = &alt_pdata;
563 }
564
565 ddata = kzalloc(sizeof(struct gpio_keys_drvdata) +
566 pdata->nbuttons * sizeof(struct gpio_button_data),
567 GFP_KERNEL);
568 input = input_allocate_device();
569 if (!ddata || !input) {
570 dev_err(dev, "failed to allocate state\n");
571 error = -ENOMEM;
572 goto fail1;
573 }
574
575 ddata->input = input;
576 ddata->n_buttons = pdata->nbuttons;
577 ddata->enable = pdata->enable;
578 ddata->disable = pdata->disable;
579 mutex_init(&ddata->disable_lock);
580
581 platform_set_drvdata(pdev, ddata);
582 input_set_drvdata(input, ddata);
583
584 input->name = pdata->name ? : pdev->name;
585 input->phys = "gpio-keys/input0";
586 input->dev.parent = &pdev->dev;
587 input->open = gpio_keys_open;
588 input->close = gpio_keys_close;
589
590 input->id.bustype = BUS_HOST;
591 input->id.vendor = 0x0001;
592 input->id.product = 0x0001;
593 input->id.version = 0x0100;
594
595 /* Enable auto repeat feature of Linux input subsystem */
596 if (pdata->rep)
597 __set_bit(EV_REP, input->evbit);
598
599 for (i = 0; i < pdata->nbuttons; i++) {
600 struct gpio_keys_button *button = &pdata->buttons[i];
601 struct gpio_button_data *bdata = &ddata->data[i];
602 unsigned int type = button->type ?: EV_KEY;
603
604 bdata->input = input;
605 bdata->button = button;
606
607 error = gpio_keys_setup_key(pdev, bdata, button);
608 if (error)
609 goto fail2;
610
611 if (button->wakeup)
612 wakeup = 1;
613
614 input_set_capability(input, type, button->code);
615 }
616
617 error = sysfs_create_group(&pdev->dev.kobj, &gpio_keys_attr_group);
618 if (error) {
619 dev_err(dev, "Unable to export keys/switches, error: %d\n",
620 error);
621 goto fail2;
622 }
623
624 error = input_register_device(input);
625 if (error) {
626 dev_err(dev, "Unable to register input device, error: %d\n",
627 error);
628 goto fail3;
629 }
630
631 /* get current state of buttons */
632 for (i = 0; i < pdata->nbuttons; i++)
633 gpio_keys_report_event(&ddata->data[i]);
634 input_sync(input);
635
636 device_init_wakeup(&pdev->dev, wakeup);
637
638 return 0;
639
640 fail3:
641 sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
642 fail2:
643 while (--i >= 0) {
644 free_irq(gpio_to_irq(pdata->buttons[i].gpio), &ddata->data[i]);
645 if (ddata->data[i].timer_debounce)
646 del_timer_sync(&ddata->data[i].timer);
647 cancel_work_sync(&ddata->data[i].work);
648 gpio_free(pdata->buttons[i].gpio);
649 }
650
651 platform_set_drvdata(pdev, NULL);
652 fail1:
653 input_free_device(input);
654 kfree(ddata);
655 /* If we have no platform_data, we allocated buttons dynamically. */
656 if (!pdev->dev.platform_data)
657 kfree(pdata->buttons);
658
659 return error;
660}
661
662static int __devexit gpio_keys_remove(struct platform_device *pdev)
663{
664 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
665 struct input_dev *input = ddata->input;
666 int i;
667
668 sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
669
670 device_init_wakeup(&pdev->dev, 0);
671
672 for (i = 0; i < ddata->n_buttons; i++) {
673 int irq = gpio_to_irq(ddata->data[i].button->gpio);
674 free_irq(irq, &ddata->data[i]);
675 if (ddata->data[i].timer_debounce)
676 del_timer_sync(&ddata->data[i].timer);
677 cancel_work_sync(&ddata->data[i].work);
678 gpio_free(ddata->data[i].button->gpio);
679 }
680
681 input_unregister_device(input);
682
683 /*
684 * If we had no platform_data, we allocated buttons dynamically, and
685 * must free them here. ddata->data[0].button is the pointer to the
686 * beginning of the allocated array.
687 */
688 if (!pdev->dev.platform_data)
689 kfree(ddata->data[0].button);
690
691 kfree(ddata);
692
693 return 0;
694}
695
696#ifdef CONFIG_PM_SLEEP
697static int gpio_keys_suspend(struct device *dev)
698{
699 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev);
700 int i;
701
702 if (device_may_wakeup(dev)) {
703 for (i = 0; i < ddata->n_buttons; i++) {
704 struct gpio_keys_button *button = ddata->data[i].button;
705 if (button->wakeup) {
706 int irq = gpio_to_irq(button->gpio);
707 enable_irq_wake(irq);
708 }
709 }
710 }
711
712 return 0;
713}
714
715static int gpio_keys_resume(struct device *dev)
716{
717 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev);
718 int i;
719
720 for (i = 0; i < ddata->n_buttons; i++) {
721
722 struct gpio_keys_button *button = ddata->data[i].button;
723 if (button->wakeup && device_may_wakeup(dev)) {
724 int irq = gpio_to_irq(button->gpio);
725 disable_irq_wake(irq);
726 }
727
728 gpio_keys_report_event(&ddata->data[i]);
729 }
730 input_sync(ddata->input);
731
732 return 0;
733}
734#endif
735
736static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume);
737
738static struct platform_driver gpio_keys_device_driver = {
739 .probe = gpio_keys_probe,
740 .remove = __devexit_p(gpio_keys_remove),
741 .driver = {
742 .name = "gpio-keys",
743 .owner = THIS_MODULE,
744 .pm = &gpio_keys_pm_ops,
745 .of_match_table = gpio_keys_of_match,
746 }
747};
748
749static int __init gpio_keys_init(void)
750{
751 return platform_driver_register(&gpio_keys_device_driver);
752}
753
754static void __exit gpio_keys_exit(void)
755{
756 platform_driver_unregister(&gpio_keys_device_driver);
757}
758
759late_initcall(gpio_keys_init);
760module_exit(gpio_keys_exit);
761
762MODULE_LICENSE("GPL");
763MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>");
764MODULE_DESCRIPTION("Keyboard driver for GPIOs");
765MODULE_ALIAS("platform:gpio-keys");