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 #include <linux/gpio/consumer.h>
  32
  33 #define BH_SKB_SIZE     2048
  34
  35 #define DRV_NAME        "gpio-keys"
  36 #define PFX     DRV_NAME ": "
  37
  38 struct bh_event {
  39         const char              *name;
  40         unsigned int            type;
  41         char                    *action;
  42         unsigned long           seen;
  43
  44         struct sk_buff          *skb;
  45         struct work_struct      work;
  46 };
  47
  48 struct bh_map {
  49         unsigned int    code;
  50         const char      *name;
  51 };
  52
  53 struct gpio_keys_button_data {
  54         struct delayed_work work;
  55         unsigned long seen;
  56         int map_entry;
  57         int last_state;
  58         int count;
  59         int threshold;
  60         int can_sleep;
  61         int irq;
  62         unsigned int software_debounce;
  63         struct gpio_desc *gpiod;
  64         const struct gpio_keys_button *b;
  65 };
  66
  67 extern u64 uevent_next_seqnum(void);
  68
  69 #define BH_MAP(_code, _name)            \
  70         {                               \
  71                 .code = (_code),        \
  72                 .name = (_name),        \
  73         }
  74
  75 static struct bh_map button_map[] = {
  76         BH_MAP(BTN_0,                   "BTN_0"),
  77         BH_MAP(BTN_1,                   "BTN_1"),
  78         BH_MAP(BTN_2,                   "BTN_2"),
  79         BH_MAP(BTN_3,                   "BTN_3"),
  80         BH_MAP(BTN_4,                   "BTN_4"),
  81         BH_MAP(BTN_5,                   "BTN_5"),
  82         BH_MAP(BTN_6,                   "BTN_6"),
  83         BH_MAP(BTN_7,                   "BTN_7"),
  84         BH_MAP(BTN_8,                   "BTN_8"),
  85         BH_MAP(BTN_9,                   "BTN_9"),
  86         BH_MAP(KEY_BRIGHTNESS_ZERO,     "brightness_zero"),
  87         BH_MAP(KEY_CONFIG,              "config"),
  88         BH_MAP(KEY_COPY,                "copy"),
  89         BH_MAP(KEY_EJECTCD,             "eject"),
  90         BH_MAP(KEY_HELP,                "help"),
  91         BH_MAP(KEY_LIGHTS_TOGGLE,       "lights_toggle"),
  92         BH_MAP(KEY_PHONE,               "phone"),
  93         BH_MAP(KEY_POWER,               "power"),
  94         BH_MAP(KEY_POWER2,              "reboot"),
  95         BH_MAP(KEY_RESTART,             "reset"),
  96         BH_MAP(KEY_RFKILL,              "rfkill"),
  97         BH_MAP(KEY_VIDEO,               "video"),
  98         BH_MAP(KEY_VOLUMEDOWN,          "volume_down"),
  99         BH_MAP(KEY_VOLUMEUP,            "volume_up"),
 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 int gpio_button_get_value(struct gpio_keys_button_data *bdata)
 241 {
 242         int val;
 243
 244         if (bdata->can_sleep)
 245                 val = !!gpio_get_value_cansleep(bdata->b->gpio);
 246         else
 247                 val = !!gpio_get_value(bdata->b->gpio);
 248
 249         return val ^ bdata->b->active_low;
 250 }
 251
 252 static void gpio_keys_handle_button(struct gpio_keys_button_data *bdata)
 253 {
 254         unsigned int type = bdata->b->type ?: EV_KEY;
 255         int state = gpio_button_get_value(bdata);
 256         unsigned long seen = jiffies;
 257
 258         pr_debug(PFX "event type=%u, code=%u, pressed=%d\n",
 259                  type, bdata->b->code, state);
 260
 261         /* is this the initialization state? */
 262         if (bdata->last_state == -1) {
 263                 /*
 264                  * Don't advertise unpressed buttons on initialization.
 265                  * Just save their state and continue otherwise this
 266                  * can cause OpenWrt to enter failsafe.
 267                  */
 268                 if (type == EV_KEY && state == 0)
 269                         goto set_state;
 270                 /*
 271                  * But we are very interested in pressed buttons and
 272                  * initial switch state. These will be reported to
 273                  * userland.
 274                  */
 275         } else if (bdata->last_state == state) {
 276                 /* reset asserted counter (only relevant for polled keys) */
 277                 bdata->count = 0;
 278                 return;
 279         }
 280
 281         if (bdata->count < bdata->threshold) {
 282                 bdata->count++;
 283                 return;
 284         }
 285
 286         if (bdata->seen == 0)
 287                 bdata->seen = seen;
 288
 289         button_hotplug_create_event(button_map[bdata->map_entry].name, type,
 290                                     (seen - bdata->seen) / HZ, state);
 291         bdata->seen = seen;
 292
 293 set_state:
 294         bdata->last_state = state;
 295         bdata->count = 0;
 296 }
 297
 298 struct gpio_keys_button_dev {
 299         int polled;
 300         struct delayed_work work;
 301
 302         struct device *dev;
 303         struct gpio_keys_platform_data *pdata;
 304         struct gpio_keys_button_data data[0];
 305 };
 306
 307 static void gpio_keys_polled_queue_work(struct gpio_keys_button_dev *bdev)
 308 {
 309         struct gpio_keys_platform_data *pdata = bdev->pdata;
 310         unsigned long delay = msecs_to_jiffies(pdata->poll_interval);
 311
 312         if (delay >= HZ)
 313                 delay = round_jiffies_relative(delay);
 314         schedule_delayed_work(&bdev->work, delay);
 315 }
 316
 317 static void gpio_keys_polled_poll(struct work_struct *work)
 318 {
 319         struct gpio_keys_button_dev *bdev =
 320                 container_of(work, struct gpio_keys_button_dev, work.work);
 321         int i;
 322
 323         for (i = 0; i < bdev->pdata->nbuttons; i++) {
 324                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 325
 326                 if (bdata->gpiod)
 327                         gpio_keys_handle_button(bdata);
 328         }
 329         gpio_keys_polled_queue_work(bdev);
 330 }
 331
 332 static void gpio_keys_polled_close(struct gpio_keys_button_dev *bdev)
 333 {
 334         struct gpio_keys_platform_data *pdata = bdev->pdata;
 335
 336         cancel_delayed_work_sync(&bdev->work);
 337
 338         if (pdata->disable)
 339                 pdata->disable(bdev->dev);
 340 }
 341
 342 static void gpio_keys_irq_work_func(struct work_struct *work)
 343 {
 344         struct gpio_keys_button_data *bdata = container_of(work,
 345                 struct gpio_keys_button_data, work.work);
 346
 347         gpio_keys_handle_button(bdata);
 348 }
 349
 350 static irqreturn_t button_handle_irq(int irq, void *_bdata)
 351 {
 352         struct gpio_keys_button_data *bdata =
 353                 (struct gpio_keys_button_data *) _bdata;
 354
 355         mod_delayed_work(system_wq, &bdata->work,
 356                          msecs_to_jiffies(bdata->software_debounce));
 357
 358         return IRQ_HANDLED;
 359 }
 360
 361 #ifdef CONFIG_OF
 362 static struct gpio_keys_platform_data *
 363 gpio_keys_get_devtree_pdata(struct device *dev)
 364 {
 365         struct device_node *node, *pp;
 366         struct gpio_keys_platform_data *pdata;
 367         struct gpio_keys_button *button;
 368         int error;
 369         int nbuttons;
 370         int i = 0;
 371
 372         node = dev->of_node;
 373         if (!node)
 374                 return NULL;
 375
 376         nbuttons = of_get_child_count(node);
 377         if (nbuttons == 0)
 378                 return NULL;
 379
 380         pdata = devm_kzalloc(dev, sizeof(*pdata) + nbuttons * (sizeof *button),
 381                 GFP_KERNEL);
 382         if (!pdata) {
 383                 error = -ENOMEM;
 384                 goto err_out;
 385         }
 386
 387         pdata->buttons = (struct gpio_keys_button *)(pdata + 1);
 388         pdata->nbuttons = nbuttons;
 389
 390         pdata->rep = !!of_get_property(node, "autorepeat", NULL);
 391         of_property_read_u32(node, "poll-interval", &pdata->poll_interval);
 392
 393         for_each_child_of_node(node, pp) {
 394                 enum of_gpio_flags flags;
 395
 396                 if (!of_find_property(pp, "gpios", NULL)) {
 397                         pdata->nbuttons--;
 398                         dev_warn(dev, "Found button without gpios\n");
 399                         continue;
 400                 }
 401
 402                 button = (struct gpio_keys_button *)(&pdata->buttons[i++]);
 403
 404                 button->irq = irq_of_parse_and_map(pp, 0);
 405
 406                 button->gpio = of_get_gpio_flags(pp, 0, &flags);
 407                 if (button->gpio < 0) {
 408                         error = button->gpio;
 409                         if (error != -ENOENT) {
 410                                 if (error != -EPROBE_DEFER)
 411                                         dev_err(dev,
 412                                                 "Failed to get gpio flags, error: %d\n",
 413                                                 error);
 414                                 return ERR_PTR(error);
 415                         }
 416                 } else {
 417                         button->active_low = !!(flags & OF_GPIO_ACTIVE_LOW);
 418                 }
 419
 420                 if (of_property_read_u32(pp, "linux,code", &button->code)) {
 421                         dev_err(dev, "Button without keycode: 0x%x\n",
 422                                 button->gpio);
 423                         error = -EINVAL;
 424                         goto err_out;
 425                 }
 426
 427                 button->desc = of_get_property(pp, "label", NULL);
 428
 429                 if (of_property_read_u32(pp, "linux,input-type", &button->type))
 430                         button->type = EV_KEY;
 431
 432                 button->wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL);
 433
 434                 if (of_property_read_u32(pp, "debounce-interval",
 435                                         &button->debounce_interval))
 436                         button->debounce_interval = 5;
 437         }
 438
 439         if (pdata->nbuttons == 0) {
 440                 error = -EINVAL;
 441                 goto err_out;
 442         }
 443
 444         return pdata;
 445
 446 err_out:
 447         return ERR_PTR(error);
 448 }
 449
 450 static struct of_device_id gpio_keys_of_match[] = {
 451         { .compatible = "gpio-keys", },
 452         { },
 453 };
 454 MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
 455
 456 static struct of_device_id gpio_keys_polled_of_match[] = {
 457         { .compatible = "gpio-keys-polled", },
 458         { },
 459 };
 460 MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);
 461
 462 #else
 463
 464 static inline struct gpio_keys_platform_data *
 465 gpio_keys_get_devtree_pdata(struct device *dev)
 466 {
 467         return NULL;
 468 }
 469 #endif
 470
 471 static int gpio_keys_button_probe(struct platform_device *pdev,
 472                 struct gpio_keys_button_dev **_bdev, int polled)
 473 {
 474         struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
 475         struct device *dev = &pdev->dev;
 476         struct gpio_keys_button_dev *bdev;
 477         struct gpio_keys_button *buttons;
 478         int error;
 479         int i;
 480
 481         if (!pdata) {
 482                 pdata = gpio_keys_get_devtree_pdata(dev);
 483                 if (IS_ERR(pdata))
 484                         return PTR_ERR(pdata);
 485                 if (!pdata) {
 486                         dev_err(dev, "missing platform data\n");
 487                         return -EINVAL;
 488                 }
 489         }
 490
 491         if (polled && !pdata->poll_interval) {
 492                 dev_err(dev, "missing poll_interval value\n");
 493                 return -EINVAL;
 494         }
 495
 496         buttons = devm_kzalloc(dev, pdata->nbuttons * sizeof(struct gpio_keys_button),
 497                        GFP_KERNEL);
 498         if (!buttons) {
 499                 dev_err(dev, "no memory for button data\n");
 500                 return -ENOMEM;
 501         }
 502         memcpy(buttons, pdata->buttons, pdata->nbuttons * sizeof(struct gpio_keys_button));
 503
 504         bdev = devm_kzalloc(dev, sizeof(struct gpio_keys_button_dev) +
 505                        pdata->nbuttons * sizeof(struct gpio_keys_button_data),
 506                        GFP_KERNEL);
 507         if (!bdev) {
 508                 dev_err(dev, "no memory for private data\n");
 509                 return -ENOMEM;
 510         }
 511
 512         bdev->polled = polled;
 513
 514         for (i = 0; i < pdata->nbuttons; i++) {
 515                 struct gpio_keys_button *button = &buttons[i];
 516                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 517                 unsigned int gpio = button->gpio;
 518
 519                 if (button->wakeup) {
 520                         dev_err(dev, "does not support wakeup\n");
 521                         return -EINVAL;
 522                 }
 523
 524                 bdata->map_entry = button_get_index(button->code);
 525                 if (bdata->map_entry < 0) {
 526                         dev_warn(dev, "does not support key code:%u\n",
 527                                 button->code);
 528                         continue;
 529                 }
 530
 531                 if (!(button->type == 0 || button->type == EV_KEY ||
 532                       button->type == EV_SW)) {
 533                         dev_warn(dev, "only supports buttons or switches\n");
 534                         continue;
 535                 }
 536
 537                 error = devm_gpio_request(dev, gpio,
 538                                      button->desc ? button->desc : DRV_NAME);
 539                 if (error) {
 540                         dev_err(dev, "unable to claim gpio %u, err=%d\n",
 541                                 gpio, error);
 542                         return error;
 543                 }
 544                 bdata->gpiod = gpio_to_desc(gpio);
 545                 if (!bdata->gpiod)
 546                         return -EINVAL;
 547
 548                 error = gpio_direction_input(gpio);
 549                 if (error) {
 550                         dev_err(dev,
 551                                 "unable to set direction on gpio %u, err=%d\n",
 552                                 gpio, error);
 553                         return error;
 554                 }
 555
 556                 bdata->can_sleep = gpio_cansleep(gpio);
 557                 bdata->last_state = -1; /* Unknown state on boot */
 558
 559                 if (bdev->polled) {
 560                         bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
 561                                                         pdata->poll_interval);
 562                 } else {
 563                         /* bdata->threshold = 0; already initialized */
 564
 565                         if (button->debounce_interval) {
 566                                 error = gpiod_set_debounce(bdata->gpiod,
 567                                         button->debounce_interval * 1000);
 568                                 /*
 569                                  * use timer if gpiolib doesn't provide
 570                                  * debounce.
 571                                  */
 572                                 if (error < 0) {
 573                                         bdata->software_debounce =
 574                                                 button->debounce_interval;
 575                                 }
 576                         }
 577                 }
 578
 579                 bdata->b = &pdata->buttons[i];
 580         }
 581
 582         bdev->dev = &pdev->dev;
 583         bdev->pdata = pdata;
 584         platform_set_drvdata(pdev, bdev);
 585
 586         *_bdev = bdev;
 587
 588         return 0;
 589 }
 590
 591 static int gpio_keys_probe(struct platform_device *pdev)
 592 {
 593         struct gpio_keys_platform_data *pdata;
 594         struct gpio_keys_button_dev *bdev;
 595         int ret, i;
 596
 597
 598         ret = gpio_keys_button_probe(pdev, &bdev, 0);
 599
 600         if (ret)
 601                 return ret;
 602
 603         pdata = bdev->pdata;
 604         for (i = 0; i < pdata->nbuttons; i++) {
 605                 const struct gpio_keys_button *button = &pdata->buttons[i];
 606                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 607                 unsigned long irqflags = IRQF_ONESHOT;
 608
 609                 INIT_DELAYED_WORK(&bdata->work, gpio_keys_irq_work_func);
 610
 611                 if (!bdata->gpiod)
 612                         continue;
 613
 614                 if (!button->irq) {
 615                         bdata->irq = gpio_to_irq(button->gpio);
 616
 617                         if (bdata->irq < 0) {
 618                                 dev_err(&pdev->dev, "failed to get irq for gpio:%d\n",
 619                                         button->gpio);
 620                                 continue;
 621                         }
 622
 623                         irqflags |= IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
 624                 } else {
 625                         bdata->irq = button->irq;
 626                 }
 627
 628                 schedule_delayed_work(&bdata->work,
 629                                       msecs_to_jiffies(bdata->software_debounce));
 630
 631                 ret = devm_request_threaded_irq(&pdev->dev,
 632                         bdata->irq, NULL, button_handle_irq,
 633                         irqflags, dev_name(&pdev->dev), bdata);
 634
 635                 if (ret < 0) {
 636                         bdata->irq = 0;
 637                         dev_err(&pdev->dev, "failed to request irq:%d for gpio:%d\n",
 638                                 bdata->irq, button->gpio);
 639                         continue;
 640                 } else {
 641                         dev_dbg(&pdev->dev, "gpio:%d has irq:%d\n",
 642                                 button->gpio, bdata->irq);
 643                 }
 644         }
 645
 646         return 0;
 647 }
 648
 649 static int gpio_keys_polled_probe(struct platform_device *pdev)
 650 {
 651         struct gpio_keys_platform_data *pdata;
 652         struct gpio_keys_button_dev *bdev;
 653         int ret;
 654
 655         ret = gpio_keys_button_probe(pdev, &bdev, 1);
 656
 657         if (ret)
 658                 return ret;
 659
 660         INIT_DELAYED_WORK(&bdev->work, gpio_keys_polled_poll);
 661
 662         pdata = bdev->pdata;
 663
 664         if (pdata->enable)
 665                 pdata->enable(bdev->dev);
 666
 667         gpio_keys_polled_queue_work(bdev);
 668
 669         return ret;
 670 }
 671
 672 static void gpio_keys_irq_close(struct gpio_keys_button_dev *bdev)
 673 {
 674         struct gpio_keys_platform_data *pdata = bdev->pdata;
 675         size_t i;
 676
 677         for (i = 0; i < pdata->nbuttons; i++) {
 678                 struct gpio_keys_button_data *bdata = &bdev->data[i];
 679
 680                 disable_irq(bdata->irq);
 681                 cancel_delayed_work_sync(&bdata->work);
 682         }
 683 }
 684
 685 static int gpio_keys_remove(struct platform_device *pdev)
 686 {
 687         struct gpio_keys_button_dev *bdev = platform_get_drvdata(pdev);
 688
 689         platform_set_drvdata(pdev, NULL);
 690
 691         if (bdev->polled)
 692                 gpio_keys_polled_close(bdev);
 693         else
 694                 gpio_keys_irq_close(bdev);
 695
 696         return 0;
 697 }
 698
 699 static struct platform_driver gpio_keys_driver = {
 700         .probe  = gpio_keys_probe,
 701         .remove = gpio_keys_remove,
 702         .driver = {
 703                 .name   = "gpio-keys",
 704                 .owner  = THIS_MODULE,
 705                 .of_match_table = of_match_ptr(gpio_keys_of_match),
 706         },
 707 };
 708
 709 static struct platform_driver gpio_keys_polled_driver = {
 710         .probe  = gpio_keys_polled_probe,
 711         .remove = gpio_keys_remove,
 712         .driver = {
 713                 .name   = "gpio-keys-polled",
 714                 .owner  = THIS_MODULE,
 715                 .of_match_table = of_match_ptr(gpio_keys_polled_of_match),
 716         },
 717 };
 718
 719 static int __init gpio_button_init(void)
 720 {
 721         int ret;
 722
 723         ret = platform_driver_register(&gpio_keys_driver);
 724         if (ret)
 725                 return ret;
 726
 727         ret = platform_driver_register(&gpio_keys_polled_driver);
 728         if (ret)
 729                 platform_driver_unregister(&gpio_keys_driver);
 730
 731         return ret;
 732 }
 733
 734 static void __exit gpio_button_exit(void)
 735 {
 736         platform_driver_unregister(&gpio_keys_driver);
 737         platform_driver_unregister(&gpio_keys_polled_driver);
 738 }
 739
 740 module_init(gpio_button_init);
 741 module_exit(gpio_button_exit);
 742
 743 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 744 MODULE_AUTHOR("Felix Fietkau <nbd@nbd.name>");
 745 MODULE_DESCRIPTION("Polled GPIO Buttons hotplug driver");
 746 MODULE_LICENSE("GPL v2");
 747 MODULE_ALIAS("platform:" DRV_NAME);