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         button_hotplug_create_event(button_map[btn].name, type,
 257                         (seen - priv->seen) / HZ, value);
 258         priv->seen = seen;
 259 }
 260
 261 struct gpio_keys_button_dev {
 262         int polled;
 263         struct delayed_work work;
 264
 265         struct device *dev;
 266         struct gpio_keys_platform_data *pdata;
 267         struct gpio_keys_button_data data[0];
 268 };
 269
 270 static int gpio_button_get_value(struct gpio_keys_button_data *bdata)
 271 {
 272         int val;
 273
 274         if (bdata->can_sleep)
 275                 val = !!gpio_get_value_cansleep(bdata->b->gpio);
 276         else
 277                 val = !!gpio_get_value(bdata->b->gpio);
 278
 279         return val ^ bdata->b->active_low;
 280 }
 281
 282 static void gpio_keys_polled_check_state(struct gpio_keys_button_data *bdata)
 283 {
 284         int state = gpio_button_get_value(bdata);
 285
 286         if (state != bdata->last_state) {
 287                 unsigned int type = bdata->b->type ?: EV_KEY;
 288
 289                 if (bdata->count < bdata->threshold) {
 290                         bdata->count++;
 291                         return;
 292                 }
 293
 294                 if (bdata->last_state != -1 || type == EV_SW)
 295                         button_hotplug_event(bdata, type, state);
 296
 297                 bdata->last_state = state;
 298         }
 299
 300         bdata->count = 0;
 301 }
 302
 303 static void gpio_keys_polled_queue_work(struct gpio_keys_button_dev *bdev)
 304 {
 305         struct gpio_keys_platform_data *pdata = bdev->pdata;
 306         unsigned long delay = msecs_to_jiffies(pdata->poll_interval);
 307
 308         if (delay >= HZ)
 309                 delay = round_jiffies_relative(delay);
 310         schedule_delayed_work(&bdev->work, delay);
 311 }
 312
 313 static void gpio_keys_polled_poll(struct work_struct *work)
 314 {
 315         struct gpio_keys_button_dev *bdev =
 316                 container_of(work, struct gpio_keys_button_dev, work.work);
 317         int i;
 318
 319         for (i = 0; i < bdev->pdata->nbuttons; i++) {
 320                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 321                 gpio_keys_polled_check_state(bdata);
 322         }
 323         gpio_keys_polled_queue_work(bdev);
 324 }
 325
 326 static void gpio_keys_polled_close(struct gpio_keys_button_dev *bdev)
 327 {
 328         struct gpio_keys_platform_data *pdata = bdev->pdata;
 329
 330         cancel_delayed_work_sync(&bdev->work);
 331
 332         if (pdata->disable)
 333                 pdata->disable(bdev->dev);
 334 }
 335
 336 static void gpio_keys_irq_work_func(struct work_struct *work)
 337 {
 338         struct gpio_keys_button_data *bdata = container_of(work,
 339                 struct gpio_keys_button_data, work.work);
 340         int state = gpio_button_get_value(bdata);
 341
 342         if (state != bdata->last_state) {
 343                 unsigned int type = bdata->b->type ?: EV_KEY;
 344
 345                 if (bdata->last_state != -1 || type == EV_SW)
 346                         button_hotplug_event(bdata, type, state);
 347
 348                 bdata->last_state = state;
 349         }
 350 }
 351
 352 static irqreturn_t button_handle_irq(int irq, void *_bdata)
 353 {
 354         struct gpio_keys_button_data *bdata =
 355                 (struct gpio_keys_button_data *) _bdata;
 356
 357         schedule_delayed_work(&bdata->work,
 358                               msecs_to_jiffies(bdata->software_debounce));
 359
 360         return IRQ_HANDLED;
 361 }
 362
 363 #ifdef CONFIG_OF
 364 static struct gpio_keys_platform_data *
 365 gpio_keys_get_devtree_pdata(struct device *dev)
 366 {
 367         struct device_node *node, *pp;
 368         struct gpio_keys_platform_data *pdata;
 369         struct gpio_keys_button *button;
 370         int error;
 371         int nbuttons;
 372         int i = 0;
 373
 374         node = dev->of_node;
 375         if (!node)
 376                 return NULL;
 377
 378         nbuttons = of_get_child_count(node);
 379         if (nbuttons == 0)
 380                 return NULL;
 381
 382         pdata = devm_kzalloc(dev, sizeof(*pdata) + nbuttons * (sizeof *button),
 383                 GFP_KERNEL);
 384         if (!pdata) {
 385                 error = -ENOMEM;
 386                 goto err_out;
 387         }
 388
 389         pdata->buttons = (struct gpio_keys_button *)(pdata + 1);
 390         pdata->nbuttons = nbuttons;
 391
 392         pdata->rep = !!of_get_property(node, "autorepeat", NULL);
 393         of_property_read_u32(node, "poll-interval", &pdata->poll_interval);
 394
 395         for_each_child_of_node(node, pp) {
 396                 enum of_gpio_flags flags;
 397
 398                 if (!of_find_property(pp, "gpios", NULL)) {
 399                         pdata->nbuttons--;
 400                         dev_warn(dev, "Found button without gpios\n");
 401                         continue;
 402                 }
 403
 404                 button = (struct gpio_keys_button *)(&pdata->buttons[i++]);
 405
 406                 button->irq = irq_of_parse_and_map(pp, 0);
 407
 408                 button->gpio = of_get_gpio_flags(pp, 0, &flags);
 409                 if (button->gpio < 0) {
 410                         error = button->gpio;
 411                         if (error != -ENOENT) {
 412                                 if (error != -EPROBE_DEFER)
 413                                         dev_err(dev,
 414                                                 "Failed to get gpio flags, error: %d\n",
 415                                                 error);
 416                                 return ERR_PTR(error);
 417                         }
 418                 } else {
 419                         button->active_low = flags & OF_GPIO_ACTIVE_LOW;
 420                 }
 421
 422                 if (of_property_read_u32(pp, "linux,code", &button->code)) {
 423                         dev_err(dev, "Button without keycode: 0x%x\n",
 424                                 button->gpio);
 425                         error = -EINVAL;
 426                         goto err_out;
 427                 }
 428
 429                 button->desc = of_get_property(pp, "label", NULL);
 430
 431                 if (of_property_read_u32(pp, "linux,input-type", &button->type))
 432                         button->type = EV_KEY;
 433
 434                 button->wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL);
 435
 436                 if (of_property_read_u32(pp, "debounce-interval",
 437                                         &button->debounce_interval))
 438                         button->debounce_interval = 5;
 439         }
 440
 441         if (pdata->nbuttons == 0) {
 442                 error = -EINVAL;
 443                 goto err_out;
 444         }
 445
 446         return pdata;
 447
 448 err_out:
 449         return ERR_PTR(error);
 450 }
 451
 452 static struct of_device_id gpio_keys_of_match[] = {
 453         { .compatible = "gpio-keys", },
 454         { },
 455 };
 456 MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
 457
 458 static struct of_device_id gpio_keys_polled_of_match[] = {
 459         { .compatible = "gpio-keys-polled", },
 460         { },
 461 };
 462 MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);
 463
 464 #else
 465
 466 static inline struct gpio_keys_platform_data *
 467 gpio_keys_get_devtree_pdata(struct device *dev)
 468 {
 469         return NULL;
 470 }
 471 #endif
 472
 473 static int gpio_keys_button_probe(struct platform_device *pdev,
 474                 struct gpio_keys_button_dev **_bdev, int polled)
 475 {
 476         struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
 477         struct device *dev = &pdev->dev;
 478         struct gpio_keys_button_dev *bdev;
 479         struct gpio_keys_button *buttons;
 480         int error;
 481         int i;
 482
 483         if (!pdata) {
 484                 pdata = gpio_keys_get_devtree_pdata(dev);
 485                 if (IS_ERR(pdata))
 486                         return PTR_ERR(pdata);
 487                 if (!pdata) {
 488                         dev_err(dev, "missing platform data\n");
 489                         return -EINVAL;
 490                 }
 491         }
 492
 493         if (polled && !pdata->poll_interval) {
 494                 dev_err(dev, "missing poll_interval value\n");
 495                 return -EINVAL;
 496         }
 497
 498         buttons = devm_kzalloc(dev, pdata->nbuttons * sizeof(struct gpio_keys_button),
 499                        GFP_KERNEL);
 500         if (!buttons) {
 501                 dev_err(dev, "no memory for button data\n");
 502                 return -ENOMEM;
 503         }
 504         memcpy(buttons, pdata->buttons, pdata->nbuttons * sizeof(struct gpio_keys_button));
 505
 506         bdev = devm_kzalloc(dev, sizeof(struct gpio_keys_button_dev) +
 507                        pdata->nbuttons * sizeof(struct gpio_keys_button_data),
 508                        GFP_KERNEL);
 509         if (!bdev) {
 510                 dev_err(dev, "no memory for private data\n");
 511                 return -ENOMEM;
 512         }
 513
 514         bdev->polled = polled;
 515
 516         for (i = 0; i < pdata->nbuttons; i++) {
 517                 struct gpio_keys_button *button = &buttons[i];
 518                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 519                 unsigned int gpio = button->gpio;
 520
 521                 if (button->wakeup) {
 522                         dev_err(dev, DRV_NAME "does not support wakeup\n");
 523                         return -EINVAL;
 524                 }
 525
 526                 error = devm_gpio_request(dev, gpio,
 527                                      button->desc ? button->desc : DRV_NAME);
 528                 if (error) {
 529                         dev_err(dev, "unable to claim gpio %u, err=%d\n",
 530                                 gpio, error);
 531                         return error;
 532                 }
 533                 bdata->gpiod = gpio_to_desc(gpio);
 534                 if (!bdata->gpiod)
 535                         return -EINVAL;
 536
 537                 error = gpio_direction_input(gpio);
 538                 if (error) {
 539                         dev_err(dev,
 540                                 "unable to set direction on gpio %u, err=%d\n",
 541                                 gpio, error);
 542                         return error;
 543                 }
 544
 545                 bdata->can_sleep = gpio_cansleep(gpio);
 546                 bdata->last_state = -1;
 547
 548                 if (bdev->polled) {
 549                         bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
 550                                                         pdata->poll_interval);
 551                 } else {
 552                         bdata->threshold = 1;
 553
 554                         if (button->debounce_interval) {
 555                                 error = gpiod_set_debounce(bdata->gpiod,
 556                                         button->debounce_interval * 1000);
 557                                 /*
 558                                  * use timer if gpiolib doesn't provide
 559                                  * debounce.
 560                                  */
 561                                 if (error < 0) {
 562                                         bdata->software_debounce =
 563                                                 button->debounce_interval;
 564                                 }
 565                         }
 566                 }
 567
 568                 bdata->b = &pdata->buttons[i];
 569         }
 570
 571         bdev->dev = &pdev->dev;
 572         bdev->pdata = pdata;
 573         platform_set_drvdata(pdev, bdev);
 574
 575         *_bdev = bdev;
 576
 577         return 0;
 578 }
 579
 580 static int gpio_keys_probe(struct platform_device *pdev)
 581 {
 582         struct gpio_keys_platform_data *pdata;
 583         struct gpio_keys_button_dev *bdev;
 584         int ret, i;
 585
 586
 587         ret = gpio_keys_button_probe(pdev, &bdev, 0);
 588
 589         if (ret)
 590                 return ret;
 591
 592         pdata = bdev->pdata;
 593         for (i = 0; i < pdata->nbuttons; i++) {
 594                 const struct gpio_keys_button *button = &pdata->buttons[i];
 595                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 596                 unsigned long irqflags = IRQF_ONESHOT;
 597
 598                 if (!button->irq) {
 599                         bdata->irq = gpio_to_irq(button->gpio);
 600
 601                         if (bdata->irq < 0) {
 602                                 dev_err(&pdev->dev, "failed to get irq for gpio:%d\n",
 603                                         button->gpio);
 604                                 continue;
 605                         }
 606
 607                         irqflags |= IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
 608                 } else {
 609                         bdata->irq = button->irq;
 610                 }
 611
 612                 INIT_DELAYED_WORK(&bdata->work, gpio_keys_irq_work_func);
 613
 614                 ret = devm_request_threaded_irq(&pdev->dev,
 615                         bdata->irq, NULL, button_handle_irq,
 616                         irqflags, dev_name(&pdev->dev), bdata);
 617
 618                 if (ret < 0) {
 619                         bdata->irq = 0;
 620                         dev_err(&pdev->dev, "failed to request irq:%d for gpio:%d\n",
 621                                 bdata->irq, button->gpio);
 622                         continue;
 623                 } else {
 624                         dev_dbg(&pdev->dev, "gpio:%d has irq:%d\n",
 625                                 button->gpio, bdata->irq);
 626                 }
 627
 628                 if (bdata->b->type == EV_SW)
 629                         button_hotplug_event(bdata, EV_SW, gpio_button_get_value(bdata));
 630         }
 631
 632         return 0;
 633 }
 634
 635 static int gpio_keys_polled_probe(struct platform_device *pdev)
 636 {
 637         struct gpio_keys_platform_data *pdata;
 638         struct gpio_keys_button_dev *bdev;
 639         int ret;
 640         int i;
 641
 642         ret = gpio_keys_button_probe(pdev, &bdev, 1);
 643
 644         if (ret)
 645                 return ret;
 646
 647         INIT_DELAYED_WORK(&bdev->work, gpio_keys_polled_poll);
 648
 649         pdata = bdev->pdata;
 650
 651         if (pdata->enable)
 652                 pdata->enable(bdev->dev);
 653
 654         for (i = 0; i < pdata->nbuttons; i++)
 655                 gpio_keys_polled_check_state(&bdev->data[i]);
 656
 657         gpio_keys_polled_queue_work(bdev);
 658
 659         return ret;
 660 }
 661
 662 static void gpio_keys_irq_close(struct gpio_keys_button_dev *bdev)
 663 {
 664         struct gpio_keys_platform_data *pdata = bdev->pdata;
 665         size_t i;
 666
 667         for (i = 0; i < pdata->nbuttons; i++) {
 668                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 669
 670                 disable_irq(bdata->irq);
 671                 cancel_delayed_work_sync(&bdata->work);
 672         }
 673 }
 674
 675 static int gpio_keys_remove(struct platform_device *pdev)
 676 {
 677         struct gpio_keys_button_dev *bdev = platform_get_drvdata(pdev);
 678
 679         platform_set_drvdata(pdev, NULL);
 680
 681         if (bdev->polled)
 682                 gpio_keys_polled_close(bdev);
 683         else
 684                 gpio_keys_irq_close(bdev);
 685
 686         return 0;
 687 }
 688
 689 static struct platform_driver gpio_keys_driver = {
 690         .probe  = gpio_keys_probe,
 691         .remove = gpio_keys_remove,
 692         .driver = {
 693                 .name   = "gpio-keys",
 694                 .owner  = THIS_MODULE,
 695                 .of_match_table = of_match_ptr(gpio_keys_of_match),
 696         },
 697 };
 698
 699 static struct platform_driver gpio_keys_polled_driver = {
 700         .probe  = gpio_keys_polled_probe,
 701         .remove = gpio_keys_remove,
 702         .driver = {
 703                 .name   = "gpio-keys-polled",
 704                 .owner  = THIS_MODULE,
 705                 .of_match_table = of_match_ptr(gpio_keys_polled_of_match),
 706         },
 707 };
 708
 709 static int __init gpio_button_init(void)
 710 {
 711         int ret;
 712
 713         ret = platform_driver_register(&gpio_keys_driver);
 714         if (ret)
 715                 return ret;
 716
 717         ret = platform_driver_register(&gpio_keys_polled_driver);
 718         if (ret)
 719                 platform_driver_unregister(&gpio_keys_driver);
 720
 721         return ret;
 722 }
 723
 724 static void __exit gpio_button_exit(void)
 725 {
 726         platform_driver_unregister(&gpio_keys_driver);
 727         platform_driver_unregister(&gpio_keys_polled_driver);
 728 }
 729
 730 module_init(gpio_button_init);
 731 module_exit(gpio_button_exit);
 732
 733 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 734 MODULE_AUTHOR("Felix Fietkau <nbd@nbd.name>");
 735 MODULE_DESCRIPTION("Polled GPIO Buttons hotplug driver");
 736 MODULE_LICENSE("GPL v2");
 737 MODULE_ALIAS("platform:" DRV_NAME);