package/kernel/gpio-button-hotplug/src/gpio-button-hotplug.c

   1 /*
   2  *  GPIO Button Hotplug driver
   3  *
   4  *  Copyright (C) 2012 Felix Fietkau <nbd@nbd.name>
   5  *  Copyright (C) 2008-2010 Gabor Juhos <juhosg@openwrt.org>
   6  *
   7  *  Based on the diag.c - GPIO interface driver for Broadcom boards
   8  *    Copyright (C) 2006 Mike Baker <mbm@openwrt.org>,
   9  *    Copyright (C) 2006-2007 Felix Fietkau <nbd@nbd.name>
  10  *    Copyright (C) 2008 Andy Boyett <agb@openwrt.org>
  11  *
  12  *  This program is free software; you can redistribute it and/or modify it
  13  *  under the terms of the GNU General Public License version 2 as published
  14  *  by the Free Software Foundation.
  15  */
  16
  17 #include <linux/module.h>
  18 #include <linux/version.h>
  19 #include <linux/kmod.h>
  20
  21 #include <linux/workqueue.h>
  22 #include <linux/skbuff.h>
  23 #include <linux/netlink.h>
  24 #include <linux/kobject.h>
  25 #include <linux/input.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/platform_device.h>
  28 #include <linux/of_gpio.h>
  29 #include <linux/of_irq.h>
  30 #include <linux/gpio_keys.h>
  31
  32 #define BH_SKB_SIZE     2048
  33
  34 #define DRV_NAME        "gpio-keys"
  35 #define PFX     DRV_NAME ": "
  36
  37 struct bh_priv {
  38         unsigned long           seen;
  39 };
  40
  41 struct bh_event {
  42         const char              *name;
  43         unsigned int            type;
  44         char                    *action;
  45         unsigned long           seen;
  46
  47         struct sk_buff          *skb;
  48         struct work_struct      work;
  49 };
  50
  51 struct bh_map {
  52         unsigned int    code;
  53         const char      *name;
  54 };
  55
  56 struct gpio_keys_button_data {
  57         struct delayed_work work;
  58         struct bh_priv bh;
  59         int last_state;
  60         int count;
  61         int threshold;
  62         int can_sleep;
  63         int irq;
  64         unsigned int software_debounce;
  65         struct gpio_desc *gpiod;
  66         const struct gpio_keys_button *b;
  67 };
  68
  69 extern u64 uevent_next_seqnum(void);
  70
  71 #define BH_MAP(_code, _name)            \
  72         {                               \
  73                 .code = (_code),        \
  74                 .name = (_name),        \
  75         }
  76
  77 static struct bh_map button_map[] = {
  78         BH_MAP(BTN_0,                   "BTN_0"),
  79         BH_MAP(BTN_1,                   "BTN_1"),
  80         BH_MAP(BTN_2,                   "BTN_2"),
  81         BH_MAP(BTN_3,                   "BTN_3"),
  82         BH_MAP(BTN_4,                   "BTN_4"),
  83         BH_MAP(BTN_5,                   "BTN_5"),
  84         BH_MAP(BTN_6,                   "BTN_6"),
  85         BH_MAP(BTN_7,                   "BTN_7"),
  86         BH_MAP(BTN_8,                   "BTN_8"),
  87         BH_MAP(BTN_9,                   "BTN_9"),
  88         BH_MAP(KEY_BRIGHTNESS_ZERO,     "brightness_zero"),
  89         BH_MAP(KEY_CONFIG,              "config"),
  90         BH_MAP(KEY_COPY,                "copy"),
  91         BH_MAP(KEY_EJECTCD,             "eject"),
  92         BH_MAP(KEY_HELP,                "help"),
  93         BH_MAP(KEY_LIGHTS_TOGGLE,       "lights_toggle"),
  94         BH_MAP(KEY_PHONE,               "phone"),
  95         BH_MAP(KEY_POWER,               "power"),
  96         BH_MAP(KEY_POWER2,              "reboot"),
  97         BH_MAP(KEY_RESTART,             "reset"),
  98         BH_MAP(KEY_RFKILL,              "rfkill"),
  99         BH_MAP(KEY_VIDEO,               "video"),
 100         BH_MAP(KEY_WIMAX,               "wwan"),
 101         BH_MAP(KEY_WLAN,                "wlan"),
 102         BH_MAP(KEY_WPS_BUTTON,          "wps"),
 103 };
 104
 105 /* -------------------------------------------------------------------------*/
 106
 107 static __printf(3, 4)
 108 int bh_event_add_var(struct bh_event *event, int argv, const char *format, ...)
 109 {
 110         static char buf[128];
 111         char *s;
 112         va_list args;
 113         int len;
 114
 115         if (argv)
 116                 return 0;
 117
 118         va_start(args, format);
 119         len = vsnprintf(buf, sizeof(buf), format, args);
 120         va_end(args);
 121
 122         if (len >= sizeof(buf)) {
 123                 WARN(1, "buffer size too small");
 124                 return -ENOMEM;
 125         }
 126
 127         s = skb_put(event->skb, len + 1);
 128         strcpy(s, buf);
 129
 130         pr_debug(PFX "added variable '%s'\n", s);
 131
 132         return 0;
 133 }
 134
 135 static int button_hotplug_fill_event(struct bh_event *event)
 136 {
 137         int ret;
 138
 139         ret = bh_event_add_var(event, 0, "HOME=%s", "/");
 140         if (ret)
 141                 return ret;
 142
 143         ret = bh_event_add_var(event, 0, "PATH=%s",
 144                                         "/sbin:/bin:/usr/sbin:/usr/bin");
 145         if (ret)
 146                 return ret;
 147
 148         ret = bh_event_add_var(event, 0, "SUBSYSTEM=%s", "button");
 149         if (ret)
 150                 return ret;
 151
 152         ret = bh_event_add_var(event, 0, "ACTION=%s", event->action);
 153         if (ret)
 154                 return ret;
 155
 156         ret = bh_event_add_var(event, 0, "BUTTON=%s", event->name);
 157         if (ret)
 158                 return ret;
 159
 160         if (event->type == EV_SW) {
 161                 ret = bh_event_add_var(event, 0, "TYPE=%s", "switch");
 162                 if (ret)
 163                         return ret;
 164         }
 165
 166         ret = bh_event_add_var(event, 0, "SEEN=%ld", event->seen);
 167         if (ret)
 168                 return ret;
 169
 170         ret = bh_event_add_var(event, 0, "SEQNUM=%llu", uevent_next_seqnum());
 171
 172         return ret;
 173 }
 174
 175 static void button_hotplug_work(struct work_struct *work)
 176 {
 177         struct bh_event *event = container_of(work, struct bh_event, work);
 178         int ret = 0;
 179
 180         event->skb = alloc_skb(BH_SKB_SIZE, GFP_KERNEL);
 181         if (!event->skb)
 182                 goto out_free_event;
 183
 184         ret = bh_event_add_var(event, 0, "%s@", event->action);
 185         if (ret)
 186                 goto out_free_skb;
 187
 188         ret = button_hotplug_fill_event(event);
 189         if (ret)
 190                 goto out_free_skb;
 191
 192         NETLINK_CB(event->skb).dst_group = 1;
 193         broadcast_uevent(event->skb, 0, 1, GFP_KERNEL);
 194
 195  out_free_skb:
 196         if (ret) {
 197                 pr_err(PFX "work error %d\n", ret);
 198                 kfree_skb(event->skb);
 199         }
 200  out_free_event:
 201         kfree(event);
 202 }
 203
 204 static int button_hotplug_create_event(const char *name, unsigned int type,
 205                 unsigned long seen, int pressed)
 206 {
 207         struct bh_event *event;
 208
 209         pr_debug(PFX "create event, name=%s, seen=%lu, pressed=%d\n",
 210                  name, seen, pressed);
 211
 212         event = kzalloc(sizeof(*event), GFP_KERNEL);
 213         if (!event)
 214                 return -ENOMEM;
 215
 216         event->name = name;
 217         event->type = type;
 218         event->seen = seen;
 219         event->action = pressed ? "pressed" : "released";
 220
 221         INIT_WORK(&event->work, (void *)(void *)button_hotplug_work);
 222         schedule_work(&event->work);
 223
 224         return 0;
 225 }
 226
 227 /* -------------------------------------------------------------------------*/
 228
 229 static int button_get_index(unsigned int code)
 230 {
 231         int i;
 232
 233         for (i = 0; i < ARRAY_SIZE(button_map); i++)
 234                 if (button_map[i].code == code)
 235                         return i;
 236
 237         return -1;
 238 }
 239
 240 static void button_hotplug_event(struct gpio_keys_button_data *data,
 241                            unsigned int type, int value)
 242 {
 243         struct bh_priv *priv = &data->bh;
 244         unsigned long seen = jiffies;
 245         int btn;
 246
 247         pr_debug(PFX "event type=%u, code=%u, value=%d\n", type, data->b->code, value);
 248
 249         if ((type != EV_KEY) && (type != EV_SW))
 250                 return;
 251
 252         btn = button_get_index(data->b->code);
 253         if (btn < 0)
 254                 return;
 255
 256         if (priv->seen == 0)
 257                 priv->seen = seen;
 258
 259         button_hotplug_create_event(button_map[btn].name, type,
 260                         (seen - priv->seen) / HZ, value);
 261         priv->seen = seen;
 262 }
 263
 264 struct gpio_keys_button_dev {
 265         int polled;
 266         struct delayed_work work;
 267
 268         struct device *dev;
 269         struct gpio_keys_platform_data *pdata;
 270         struct gpio_keys_button_data data[0];
 271 };
 272
 273 static int gpio_button_get_value(struct gpio_keys_button_data *bdata)
 274 {
 275         int val;
 276
 277         if (bdata->can_sleep)
 278                 val = !!gpio_get_value_cansleep(bdata->b->gpio);
 279         else
 280                 val = !!gpio_get_value(bdata->b->gpio);
 281
 282         return val ^ bdata->b->active_low;
 283 }
 284
 285 static void gpio_keys_polled_check_state(struct gpio_keys_button_data *bdata)
 286 {
 287         int state = gpio_button_get_value(bdata);
 288
 289         if (state != bdata->last_state) {
 290                 unsigned int type = bdata->b->type ?: EV_KEY;
 291
 292                 if (bdata->count < bdata->threshold) {
 293                         bdata->count++;
 294                         return;
 295                 }
 296
 297                 if (bdata->last_state != -1 || type == EV_SW)
 298                         button_hotplug_event(bdata, type, state);
 299
 300                 bdata->last_state = state;
 301         }
 302
 303         bdata->count = 0;
 304 }
 305
 306 static void gpio_keys_polled_queue_work(struct gpio_keys_button_dev *bdev)
 307 {
 308         struct gpio_keys_platform_data *pdata = bdev->pdata;
 309         unsigned long delay = msecs_to_jiffies(pdata->poll_interval);
 310
 311         if (delay >= HZ)
 312                 delay = round_jiffies_relative(delay);
 313         schedule_delayed_work(&bdev->work, delay);
 314 }
 315
 316 static void gpio_keys_polled_poll(struct work_struct *work)
 317 {
 318         struct gpio_keys_button_dev *bdev =
 319                 container_of(work, struct gpio_keys_button_dev, work.work);
 320         int i;
 321
 322         for (i = 0; i < bdev->pdata->nbuttons; i++) {
 323                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 324                 gpio_keys_polled_check_state(bdata);
 325         }
 326         gpio_keys_polled_queue_work(bdev);
 327 }
 328
 329 static void gpio_keys_polled_close(struct gpio_keys_button_dev *bdev)
 330 {
 331         struct gpio_keys_platform_data *pdata = bdev->pdata;
 332
 333         cancel_delayed_work_sync(&bdev->work);
 334
 335         if (pdata->disable)
 336                 pdata->disable(bdev->dev);
 337 }
 338
 339 static void gpio_keys_irq_work_func(struct work_struct *work)
 340 {
 341         struct gpio_keys_button_data *bdata = container_of(work,
 342                 struct gpio_keys_button_data, work.work);
 343         int state = gpio_button_get_value(bdata);
 344
 345         if (state != bdata->last_state) {
 346                 unsigned int type = bdata->b->type ?: EV_KEY;
 347
 348                 if (bdata->last_state != -1 || type == EV_SW)
 349                         button_hotplug_event(bdata, type, state);
 350
 351                 bdata->last_state = state;
 352         }
 353 }
 354
 355 static irqreturn_t button_handle_irq(int irq, void *_bdata)
 356 {
 357         struct gpio_keys_button_data *bdata =
 358                 (struct gpio_keys_button_data *) _bdata;
 359
 360         schedule_delayed_work(&bdata->work,
 361                               msecs_to_jiffies(bdata->software_debounce));
 362
 363         return IRQ_HANDLED;
 364 }
 365
 366 #ifdef CONFIG_OF
 367 static struct gpio_keys_platform_data *
 368 gpio_keys_get_devtree_pdata(struct device *dev)
 369 {
 370         struct device_node *node, *pp;
 371         struct gpio_keys_platform_data *pdata;
 372         struct gpio_keys_button *button;
 373         int error;
 374         int nbuttons;
 375         int i = 0;
 376
 377         node = dev->of_node;
 378         if (!node)
 379                 return NULL;
 380
 381         nbuttons = of_get_child_count(node);
 382         if (nbuttons == 0)
 383                 return NULL;
 384
 385         pdata = devm_kzalloc(dev, sizeof(*pdata) + nbuttons * (sizeof *button),
 386                 GFP_KERNEL);
 387         if (!pdata) {
 388                 error = -ENOMEM;
 389                 goto err_out;
 390         }
 391
 392         pdata->buttons = (struct gpio_keys_button *)(pdata + 1);
 393         pdata->nbuttons = nbuttons;
 394
 395         pdata->rep = !!of_get_property(node, "autorepeat", NULL);
 396         of_property_read_u32(node, "poll-interval", &pdata->poll_interval);
 397
 398         for_each_child_of_node(node, pp) {
 399                 enum of_gpio_flags flags;
 400
 401                 if (!of_find_property(pp, "gpios", NULL)) {
 402                         pdata->nbuttons--;
 403                         dev_warn(dev, "Found button without gpios\n");
 404                         continue;
 405                 }
 406
 407                 button = (struct gpio_keys_button *)(&pdata->buttons[i++]);
 408
 409                 button->irq = irq_of_parse_and_map(pp, 0);
 410
 411                 button->gpio = of_get_gpio_flags(pp, 0, &flags);
 412                 if (button->gpio < 0) {
 413                         error = button->gpio;
 414                         if (error != -ENOENT) {
 415                                 if (error != -EPROBE_DEFER)
 416                                         dev_err(dev,
 417                                                 "Failed to get gpio flags, error: %d\n",
 418                                                 error);
 419                                 return ERR_PTR(error);
 420                         }
 421                 } else {
 422                         button->active_low = flags & OF_GPIO_ACTIVE_LOW;
 423                 }
 424
 425                 if (of_property_read_u32(pp, "linux,code", &button->code)) {
 426                         dev_err(dev, "Button without keycode: 0x%x\n",
 427                                 button->gpio);
 428                         error = -EINVAL;
 429                         goto err_out;
 430                 }
 431
 432                 button->desc = of_get_property(pp, "label", NULL);
 433
 434                 if (of_property_read_u32(pp, "linux,input-type", &button->type))
 435                         button->type = EV_KEY;
 436
 437                 button->wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL);
 438
 439                 if (of_property_read_u32(pp, "debounce-interval",
 440                                         &button->debounce_interval))
 441                         button->debounce_interval = 5;
 442         }
 443
 444         if (pdata->nbuttons == 0) {
 445                 error = -EINVAL;
 446                 goto err_out;
 447         }
 448
 449         return pdata;
 450
 451 err_out:
 452         return ERR_PTR(error);
 453 }
 454
 455 static struct of_device_id gpio_keys_of_match[] = {
 456         { .compatible = "gpio-keys", },
 457         { },
 458 };
 459 MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
 460
 461 static struct of_device_id gpio_keys_polled_of_match[] = {
 462         { .compatible = "gpio-keys-polled", },
 463         { },
 464 };
 465 MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);
 466
 467 #else
 468
 469 static inline struct gpio_keys_platform_data *
 470 gpio_keys_get_devtree_pdata(struct device *dev)
 471 {
 472         return NULL;
 473 }
 474 #endif
 475
 476 static int gpio_keys_button_probe(struct platform_device *pdev,
 477                 struct gpio_keys_button_dev **_bdev, int polled)
 478 {
 479         struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
 480         struct device *dev = &pdev->dev;
 481         struct gpio_keys_button_dev *bdev;
 482         struct gpio_keys_button *buttons;
 483         int error;
 484         int i;
 485
 486         if (!pdata) {
 487                 pdata = gpio_keys_get_devtree_pdata(dev);
 488                 if (IS_ERR(pdata))
 489                         return PTR_ERR(pdata);
 490                 if (!pdata) {
 491                         dev_err(dev, "missing platform data\n");
 492                         return -EINVAL;
 493                 }
 494         }
 495
 496         if (polled && !pdata->poll_interval) {
 497                 dev_err(dev, "missing poll_interval value\n");
 498                 return -EINVAL;
 499         }
 500
 501         buttons = devm_kzalloc(dev, pdata->nbuttons * sizeof(struct gpio_keys_button),
 502                        GFP_KERNEL);
 503         if (!buttons) {
 504                 dev_err(dev, "no memory for button data\n");
 505                 return -ENOMEM;
 506         }
 507         memcpy(buttons, pdata->buttons, pdata->nbuttons * sizeof(struct gpio_keys_button));
 508
 509         bdev = devm_kzalloc(dev, sizeof(struct gpio_keys_button_dev) +
 510                        pdata->nbuttons * sizeof(struct gpio_keys_button_data),
 511                        GFP_KERNEL);
 512         if (!bdev) {
 513                 dev_err(dev, "no memory for private data\n");
 514                 return -ENOMEM;
 515         }
 516
 517         bdev->polled = polled;
 518
 519         for (i = 0; i < pdata->nbuttons; i++) {
 520                 struct gpio_keys_button *button = &buttons[i];
 521                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 522                 unsigned int gpio = button->gpio;
 523
 524                 if (button->wakeup) {
 525                         dev_err(dev, DRV_NAME "does not support wakeup\n");
 526                         return -EINVAL;
 527                 }
 528
 529                 error = devm_gpio_request(dev, gpio,
 530                                      button->desc ? button->desc : DRV_NAME);
 531                 if (error) {
 532                         dev_err(dev, "unable to claim gpio %u, err=%d\n",
 533                                 gpio, error);
 534                         return error;
 535                 }
 536                 bdata->gpiod = gpio_to_desc(gpio);
 537                 if (!bdata->gpiod)
 538                         return -EINVAL;
 539
 540                 error = gpio_direction_input(gpio);
 541                 if (error) {
 542                         dev_err(dev,
 543                                 "unable to set direction on gpio %u, err=%d\n",
 544                                 gpio, error);
 545                         return error;
 546                 }
 547
 548                 bdata->can_sleep = gpio_cansleep(gpio);
 549                 bdata->last_state = -1;
 550
 551                 if (bdev->polled) {
 552                         bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
 553                                                         pdata->poll_interval);
 554                 } else {
 555                         bdata->threshold = 1;
 556
 557                         if (button->debounce_interval) {
 558                                 error = gpiod_set_debounce(bdata->gpiod,
 559                                         button->debounce_interval * 1000);
 560                                 /*
 561                                  * use timer if gpiolib doesn't provide
 562                                  * debounce.
 563                                  */
 564                                 if (error < 0) {
 565                                         bdata->software_debounce =
 566                                                 button->debounce_interval;
 567                                 }
 568                         }
 569                 }
 570
 571                 bdata->b = &pdata->buttons[i];
 572         }
 573
 574         bdev->dev = &pdev->dev;
 575         bdev->pdata = pdata;
 576         platform_set_drvdata(pdev, bdev);
 577
 578         *_bdev = bdev;
 579
 580         return 0;
 581 }
 582
 583 static int gpio_keys_probe(struct platform_device *pdev)
 584 {
 585         struct gpio_keys_platform_data *pdata;
 586         struct gpio_keys_button_dev *bdev;
 587         int ret, i;
 588
 589
 590         ret = gpio_keys_button_probe(pdev, &bdev, 0);
 591
 592         if (ret)
 593                 return ret;
 594
 595         pdata = bdev->pdata;
 596         for (i = 0; i < pdata->nbuttons; i++) {
 597                 const struct gpio_keys_button *button = &pdata->buttons[i];
 598                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 599                 unsigned long irqflags = IRQF_ONESHOT;
 600
 601                 if (!button->irq) {
 602                         bdata->irq = gpio_to_irq(button->gpio);
 603
 604                         if (bdata->irq < 0) {
 605                                 dev_err(&pdev->dev, "failed to get irq for gpio:%d\n",
 606                                         button->gpio);
 607                                 continue;
 608                         }
 609
 610                         irqflags |= IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
 611                 } else {
 612                         bdata->irq = button->irq;
 613                 }
 614
 615                 INIT_DELAYED_WORK(&bdata->work, gpio_keys_irq_work_func);
 616
 617                 ret = devm_request_threaded_irq(&pdev->dev,
 618                         bdata->irq, NULL, button_handle_irq,
 619                         irqflags, dev_name(&pdev->dev), bdata);
 620
 621                 if (ret < 0) {
 622                         bdata->irq = 0;
 623                         dev_err(&pdev->dev, "failed to request irq:%d for gpio:%d\n",
 624                                 bdata->irq, button->gpio);
 625                         continue;
 626                 } else {
 627                         dev_dbg(&pdev->dev, "gpio:%d has irq:%d\n",
 628                                 button->gpio, bdata->irq);
 629                 }
 630
 631                 if (bdata->b->type == EV_SW)
 632                         button_hotplug_event(bdata, EV_SW, gpio_button_get_value(bdata));
 633         }
 634
 635         return 0;
 636 }
 637
 638 static int gpio_keys_polled_probe(struct platform_device *pdev)
 639 {
 640         struct gpio_keys_platform_data *pdata;
 641         struct gpio_keys_button_dev *bdev;
 642         int ret;
 643         int i;
 644
 645         ret = gpio_keys_button_probe(pdev, &bdev, 1);
 646
 647         if (ret)
 648                 return ret;
 649
 650         INIT_DELAYED_WORK(&bdev->work, gpio_keys_polled_poll);
 651
 652         pdata = bdev->pdata;
 653
 654         if (pdata->enable)
 655                 pdata->enable(bdev->dev);
 656
 657         for (i = 0; i < pdata->nbuttons; i++)
 658                 gpio_keys_polled_check_state(&bdev->data[i]);
 659
 660         gpio_keys_polled_queue_work(bdev);
 661
 662         return ret;
 663 }
 664
 665 static void gpio_keys_irq_close(struct gpio_keys_button_dev *bdev)
 666 {
 667         struct gpio_keys_platform_data *pdata = bdev->pdata;
 668         size_t i;
 669
 670         for (i = 0; i < pdata->nbuttons; i++) {
 671                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 672
 673                 disable_irq(bdata->irq);
 674                 cancel_delayed_work_sync(&bdata->work);
 675         }
 676 }
 677
 678 static int gpio_keys_remove(struct platform_device *pdev)
 679 {
 680         struct gpio_keys_button_dev *bdev = platform_get_drvdata(pdev);
 681
 682         platform_set_drvdata(pdev, NULL);
 683
 684         if (bdev->polled)
 685                 gpio_keys_polled_close(bdev);
 686         else
 687                 gpio_keys_irq_close(bdev);
 688
 689         return 0;
 690 }
 691
 692 static struct platform_driver gpio_keys_driver = {
 693         .probe  = gpio_keys_probe,
 694         .remove = gpio_keys_remove,
 695         .driver = {
 696                 .name   = "gpio-keys",
 697                 .owner  = THIS_MODULE,
 698                 .of_match_table = of_match_ptr(gpio_keys_of_match),
 699         },
 700 };
 701
 702 static struct platform_driver gpio_keys_polled_driver = {
 703         .probe  = gpio_keys_polled_probe,
 704         .remove = gpio_keys_remove,
 705         .driver = {
 706                 .name   = "gpio-keys-polled",
 707                 .owner  = THIS_MODULE,
 708                 .of_match_table = of_match_ptr(gpio_keys_polled_of_match),
 709         },
 710 };
 711
 712 static int __init gpio_button_init(void)
 713 {
 714         int ret;
 715
 716         ret = platform_driver_register(&gpio_keys_driver);
 717         if (ret)
 718                 return ret;
 719
 720         ret = platform_driver_register(&gpio_keys_polled_driver);
 721         if (ret)
 722                 platform_driver_unregister(&gpio_keys_driver);
 723
 724         return ret;
 725 }
 726
 727 static void __exit gpio_button_exit(void)
 728 {
 729         platform_driver_unregister(&gpio_keys_driver);
 730         platform_driver_unregister(&gpio_keys_polled_driver);
 731 }
 732
 733 module_init(gpio_button_init);
 734 module_exit(gpio_button_exit);
 735
 736 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 737 MODULE_AUTHOR("Felix Fietkau <nbd@nbd.name>");
 738 MODULE_DESCRIPTION("Polled GPIO Buttons hotplug driver");
 739 MODULE_LICENSE("GPL v2");
 740 MODULE_ALIAS("platform:" DRV_NAME);