Initial commit

package/kernel/gpio-button-hotplug/Makefile

@@ -0,0 +1,39 @@
+#
+# Copyright (C) 2008-2012 OpenWrt.org
+#
+# This is free software, licensed under the GNU General Public License v2.
+# See /LICENSE for more information.
+#
+
+include $(TOPDIR)/rules.mk
+include $(INCLUDE_DIR)/kernel.mk
+
+PKG_NAME:=gpio-button-hotplug
+PKG_RELEASE:=3
+PKG_LICENSE:=GPL-2.0
+
+include $(INCLUDE_DIR)/package.mk
+
+define KernelPackage/gpio-button-hotplug
+  SUBMENU:=GPIO support
+  TITLE:=Simple GPIO Button Hotplug driver
+  FILES:=$(PKG_BUILD_DIR)/gpio-button-hotplug.ko
+  AUTOLOAD:=$(call AutoLoad,30,gpio-button-hotplug,1)
+  KCONFIG:=
+endef
+
+define KernelPackage/gpio-button-hotplug/description
+ This is a replacement for the following in-kernel drivers:
+ 1) gpio_keys (KEYBOARD_GPIO)
+ 2) gpio_keys_polled (KEYBOARD_GPIO_POLLED)
+
+ Instead of generating input events (like in-kernel drivers do) it generates
+ uevent-s and broadcasts them. This allows disabling input subsystem which is
+ an overkill for OpenWrt simple needs.
+endef
+
+define Build/Compile
+	$(KERNEL_MAKE) M="$(PKG_BUILD_DIR)" modules
+endef
+
+$(eval $(call KernelPackage,gpio-button-hotplug))

package/kernel/gpio-button-hotplug/src/Makefile

@@ -0,0 +1 @@
+obj-m += gpio-button-hotplug.o

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

@@ -0,0 +1,739 @@
+/*
+ *  GPIO Button Hotplug driver
+ *
+ *  Copyright (C) 2012 Felix Fietkau <nbd@nbd.name>
+ *  Copyright (C) 2008-2010 Gabor Juhos <juhosg@openwrt.org>
+ *
+ *  Based on the diag.c - GPIO interface driver for Broadcom boards
+ *    Copyright (C) 2006 Mike Baker <mbm@openwrt.org>,
+ *    Copyright (C) 2006-2007 Felix Fietkau <nbd@nbd.name>
+ *    Copyright (C) 2008 Andy Boyett <agb@openwrt.org>
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under the terms of the GNU General Public License version 2 as published
+ *  by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/kmod.h>
+
+#include <linux/workqueue.h>
+#include <linux/skbuff.h>
+#include <linux/netlink.h>
+#include <linux/kobject.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/of_gpio.h>
+#include <linux/of_irq.h>
+#include <linux/gpio_keys.h>
+#include <linux/gpio/consumer.h>
+
+#define BH_SKB_SIZE	2048
+
+#define DRV_NAME	"gpio-keys"
+#define PFX	DRV_NAME ": "
+
+struct bh_event {
+	const char		*name;
+	unsigned int		type;
+	char			*action;
+	unsigned long		seen;
+
+	struct sk_buff		*skb;
+	struct work_struct	work;
+};
+
+struct bh_map {
+	unsigned int	code;
+	const char	*name;
+};
+
+struct gpio_keys_button_data {
+	struct delayed_work work;
+	unsigned long seen;
+	int map_entry;
+	int last_state;
+	int count;
+	int threshold;
+	int can_sleep;
+	int irq;
+	unsigned int software_debounce;
+	struct gpio_desc *gpiod;
+	const struct gpio_keys_button *b;
+};
+
+extern u64 uevent_next_seqnum(void);
+
+#define BH_MAP(_code, _name)		\
+	{				\
+		.code = (_code),	\
+		.name = (_name),	\
+	}
+
+static struct bh_map button_map[] = {
+	BH_MAP(BTN_0,			"BTN_0"),
+	BH_MAP(BTN_1,			"BTN_1"),
+	BH_MAP(BTN_2,			"BTN_2"),
+	BH_MAP(BTN_3,			"BTN_3"),
+	BH_MAP(BTN_4,			"BTN_4"),
+	BH_MAP(BTN_5,			"BTN_5"),
+	BH_MAP(BTN_6,			"BTN_6"),
+	BH_MAP(BTN_7,			"BTN_7"),
+	BH_MAP(BTN_8,			"BTN_8"),
+	BH_MAP(BTN_9,			"BTN_9"),
+	BH_MAP(KEY_BRIGHTNESS_ZERO,	"brightness_zero"),
+	BH_MAP(KEY_CONFIG,		"config"),
+	BH_MAP(KEY_COPY,		"copy"),
+	BH_MAP(KEY_EJECTCD,		"eject"),
+	BH_MAP(KEY_HELP,		"help"),
+	BH_MAP(KEY_LIGHTS_TOGGLE,	"lights_toggle"),
+	BH_MAP(KEY_PHONE,		"phone"),
+	BH_MAP(KEY_POWER,		"power"),
+	BH_MAP(KEY_POWER2,		"reboot"),
+	BH_MAP(KEY_RESTART,		"reset"),
+	BH_MAP(KEY_RFKILL,		"rfkill"),
+	BH_MAP(KEY_VIDEO,		"video"),
+	BH_MAP(KEY_VOLUMEDOWN,		"volume_down"),
+	BH_MAP(KEY_VOLUMEUP,		"volume_up"),
+	BH_MAP(KEY_WIMAX,		"wwan"),
+	BH_MAP(KEY_WLAN,		"wlan"),
+	BH_MAP(KEY_WPS_BUTTON,		"wps"),
+};
+
+/* -------------------------------------------------------------------------*/
+
+static __printf(3, 4)
+int bh_event_add_var(struct bh_event *event, int argv, const char *format, ...)
+{
+	char buf[128];
+	char *s;
+	va_list args;
+	int len;
+
+	if (argv)
+		return 0;
+
+	va_start(args, format);
+	len = vsnprintf(buf, sizeof(buf), format, args);
+	va_end(args);
+
+	if (len >= sizeof(buf)) {
+		WARN(1, "buffer size too small");
+		return -ENOMEM;
+	}
+
+	s = skb_put(event->skb, len + 1);
+	strcpy(s, buf);
+
+	pr_debug(PFX "added variable '%s'\n", s);
+
+	return 0;
+}
+
+static int button_hotplug_fill_event(struct bh_event *event)
+{
+	int ret;
+
+	ret = bh_event_add_var(event, 0, "HOME=%s", "/");
+	if (ret)
+		return ret;
+
+	ret = bh_event_add_var(event, 0, "PATH=%s",
+					"/sbin:/bin:/usr/sbin:/usr/bin");
+	if (ret)
+		return ret;
+
+	ret = bh_event_add_var(event, 0, "SUBSYSTEM=%s", "button");
+	if (ret)
+		return ret;
+
+	ret = bh_event_add_var(event, 0, "ACTION=%s", event->action);
+	if (ret)
+		return ret;
+
+	ret = bh_event_add_var(event, 0, "BUTTON=%s", event->name);
+	if (ret)
+		return ret;
+
+	if (event->type == EV_SW) {
+		ret = bh_event_add_var(event, 0, "TYPE=%s", "switch");
+		if (ret)
+			return ret;
+	}
+
+	ret = bh_event_add_var(event, 0, "SEEN=%ld", event->seen);
+	if (ret)
+		return ret;
+
+	ret = bh_event_add_var(event, 0, "SEQNUM=%llu", uevent_next_seqnum());
+
+	return ret;
+}
+
+static void button_hotplug_work(struct work_struct *work)
+{
+	struct bh_event *event = container_of(work, struct bh_event, work);
+	int ret = 0;
+
+	event->skb = alloc_skb(BH_SKB_SIZE, GFP_KERNEL);
+	if (!event->skb)
+		goto out_free_event;
+
+	ret = bh_event_add_var(event, 0, "%s@", event->action);
+	if (ret)
+		goto out_free_skb;
+
+	ret = button_hotplug_fill_event(event);
+	if (ret)
+		goto out_free_skb;
+
+	NETLINK_CB(event->skb).dst_group = 1;
+	broadcast_uevent(event->skb, 0, 1, GFP_KERNEL);
+
+ out_free_skb:
+	if (ret) {
+		pr_err(PFX "work error %d\n", ret);
+		kfree_skb(event->skb);
+	}
+ out_free_event:
+	kfree(event);
+}
+
+static int button_hotplug_create_event(const char *name, unsigned int type,
+		unsigned long seen, int pressed)
+{
+	struct bh_event *event;
+
+	pr_debug(PFX "create event, name=%s, seen=%lu, pressed=%d\n",
+		 name, seen, pressed);
+
+	event = kzalloc(sizeof(*event), GFP_KERNEL);
+	if (!event)
+		return -ENOMEM;
+
+	event->name = name;
+	event->type = type;
+	event->seen = seen;
+	event->action = pressed ? "pressed" : "released";
+
+	INIT_WORK(&event->work, (void *)(void *)button_hotplug_work);
+	schedule_work(&event->work);
+
+	return 0;
+}
+
+/* -------------------------------------------------------------------------*/
+
+static int button_get_index(unsigned int code)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(button_map); i++)
+		if (button_map[i].code == code)
+			return i;
+
+	return -1;
+}
+
+static int gpio_button_get_value(struct gpio_keys_button_data *bdata)
+{
+	int val;
+
+	if (bdata->can_sleep)
+		val = !!gpiod_get_value_cansleep(bdata->gpiod);
+	else
+		val = !!gpiod_get_value(bdata->gpiod);
+
+	return val;
+}
+
+static void gpio_keys_handle_button(struct gpio_keys_button_data *bdata)
+{
+	unsigned int type = bdata->b->type ?: EV_KEY;
+	int state = gpio_button_get_value(bdata);
+	unsigned long seen = jiffies;
+
+	pr_debug(PFX "event type=%u, code=%u, pressed=%d\n",
+		 type, bdata->b->code, state);
+
+	/* is this the initialization state? */
+	if (bdata->last_state == -1) {
+		/*
+		 * Don't advertise unpressed buttons on initialization.
+		 * Just save their state and continue otherwise this
+		 * can cause OpenWrt to enter failsafe.
+		 */
+		if (type == EV_KEY && state == 0)
+			goto set_state;
+		/*
+		 * But we are very interested in pressed buttons and
+		 * initial switch state. These will be reported to
+		 * userland.
+		 */
+	} else if (bdata->last_state == state) {
+		/* reset asserted counter (only relevant for polled keys) */
+		bdata->count = 0;
+		return;
+	}
+
+	if (bdata->count < bdata->threshold) {
+		bdata->count++;
+		return;
+	}
+
+	if (bdata->seen == 0)
+		bdata->seen = seen;
+
+	button_hotplug_create_event(button_map[bdata->map_entry].name, type,
+				    (seen - bdata->seen) / HZ, state);
+	bdata->seen = seen;
+
+set_state:
+	bdata->last_state = state;
+	bdata->count = 0;
+}
+
+struct gpio_keys_button_dev {
+	int polled;
+	struct delayed_work work;
+
+	struct device *dev;
+	struct gpio_keys_platform_data *pdata;
+	struct gpio_keys_button_data data[0];
+};
+
+static void gpio_keys_polled_queue_work(struct gpio_keys_button_dev *bdev)
+{
+	struct gpio_keys_platform_data *pdata = bdev->pdata;
+	unsigned long delay = msecs_to_jiffies(pdata->poll_interval);
+
+	if (delay >= HZ)
+		delay = round_jiffies_relative(delay);
+	schedule_delayed_work(&bdev->work, delay);
+}
+
+static void gpio_keys_polled_poll(struct work_struct *work)
+{
+	struct gpio_keys_button_dev *bdev =
+		container_of(work, struct gpio_keys_button_dev, work.work);
+	int i;
+
+	for (i = 0; i < bdev->pdata->nbuttons; i++) {
+		struct gpio_keys_button_data *bdata = &bdev->data[i];
+
+		if (bdata->gpiod)
+			gpio_keys_handle_button(bdata);
+	}
+	gpio_keys_polled_queue_work(bdev);
+}
+
+static void gpio_keys_polled_close(struct gpio_keys_button_dev *bdev)
+{
+	struct gpio_keys_platform_data *pdata = bdev->pdata;
+
+	cancel_delayed_work_sync(&bdev->work);
+
+	if (pdata->disable)
+		pdata->disable(bdev->dev);
+}
+
+static void gpio_keys_irq_work_func(struct work_struct *work)
+{
+	struct gpio_keys_button_data *bdata = container_of(work,
+		struct gpio_keys_button_data, work.work);
+
+	gpio_keys_handle_button(bdata);
+}
+
+static irqreturn_t button_handle_irq(int irq, void *_bdata)
+{
+	struct gpio_keys_button_data *bdata =
+		(struct gpio_keys_button_data *) _bdata;
+
+	mod_delayed_work(system_wq, &bdata->work,
+			 msecs_to_jiffies(bdata->software_debounce));
+
+	return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_OF
+static struct gpio_keys_platform_data *
+gpio_keys_get_devtree_pdata(struct device *dev)
+{
+	struct device_node *node, *pp;
+	struct gpio_keys_platform_data *pdata;
+	struct gpio_keys_button *button;
+	int nbuttons;
+	int i = 0;
+
+	node = dev->of_node;
+	if (!node)
+		return NULL;
+
+	nbuttons = of_get_child_count(node);
+	if (nbuttons == 0)
+		return ERR_PTR(-EINVAL);
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata) + nbuttons * (sizeof *button),
+		GFP_KERNEL);
+	if (!pdata)
+		return ERR_PTR(-ENOMEM);
+
+	pdata->buttons = (struct gpio_keys_button *)(pdata + 1);
+	pdata->nbuttons = nbuttons;
+
+	pdata->rep = !!of_get_property(node, "autorepeat", NULL);
+	of_property_read_u32(node, "poll-interval", &pdata->poll_interval);
+
+	for_each_child_of_node(node, pp) {
+		button = (struct gpio_keys_button *)(&pdata->buttons[i++]);
+
+		if (of_property_read_u32(pp, "linux,code", &button->code)) {
+			dev_err(dev, "Button node '%s' without keycode\n",
+				pp->full_name);
+			of_node_put(pp);
+			return ERR_PTR(-EINVAL);
+		}
+
+		button->desc = of_get_property(pp, "label", NULL);
+
+		if (of_property_read_u32(pp, "linux,input-type", &button->type))
+			button->type = EV_KEY;
+
+		button->wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL);
+
+		if (of_property_read_u32(pp, "debounce-interval",
+					&button->debounce_interval))
+			button->debounce_interval = 5;
+
+		button->irq = irq_of_parse_and_map(pp, 0);
+		button->gpio = -ENOENT; /* mark this as device-tree */
+	}
+
+	return pdata;
+}
+
+static struct of_device_id gpio_keys_of_match[] = {
+	{ .compatible = "gpio-keys", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
+
+static struct of_device_id gpio_keys_polled_of_match[] = {
+	{ .compatible = "gpio-keys-polled", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);
+
+#else
+
+static inline struct gpio_keys_platform_data *
+gpio_keys_get_devtree_pdata(struct device *dev)
+{
+	return NULL;
+}
+#endif
+
+static int gpio_keys_button_probe(struct platform_device *pdev,
+		struct gpio_keys_button_dev **_bdev, int polled)
+{
+	struct device *dev = &pdev->dev;
+	struct gpio_keys_platform_data *pdata = dev_get_platdata(dev);
+	struct gpio_keys_button_dev *bdev;
+	struct gpio_keys_button *buttons;
+	struct device_node *prev = NULL;
+	int error = 0;
+	int i;
+
+	if (!pdata) {
+		pdata = gpio_keys_get_devtree_pdata(dev);
+		if (IS_ERR(pdata))
+			return PTR_ERR(pdata);
+		if (!pdata) {
+			dev_err(dev, "missing platform data\n");
+			return -EINVAL;
+		}
+	}
+
+	if (polled && !pdata->poll_interval) {
+		dev_err(dev, "missing poll_interval value\n");
+		return -EINVAL;
+	}
+
+	buttons = devm_kzalloc(dev, pdata->nbuttons * sizeof(struct gpio_keys_button),
+		       GFP_KERNEL);
+	if (!buttons) {
+		dev_err(dev, "no memory for button data\n");
+		return -ENOMEM;
+	}
+	memcpy(buttons, pdata->buttons, pdata->nbuttons * sizeof(struct gpio_keys_button));
+
+	bdev = devm_kzalloc(dev, sizeof(struct gpio_keys_button_dev) +
+		       pdata->nbuttons * sizeof(struct gpio_keys_button_data),
+		       GFP_KERNEL);
+	if (!bdev) {
+		dev_err(dev, "no memory for private data\n");
+		return -ENOMEM;
+	}
+
+	bdev->polled = polled;
+
+	for (i = 0; i < pdata->nbuttons; i++) {
+		struct gpio_keys_button *button = &buttons[i];
+		struct gpio_keys_button_data *bdata = &bdev->data[i];
+		const char *desc = button->desc ? button->desc : DRV_NAME;
+
+		if (button->wakeup) {
+			dev_err(dev, "does not support wakeup\n");
+			error = -EINVAL;
+			goto out;
+		}
+
+		bdata->map_entry = button_get_index(button->code);
+		if (bdata->map_entry < 0) {
+			dev_err(dev, "does not support key code:%u\n",
+				button->code);
+			error = -EINVAL;
+			goto out;
+		}
+
+		if (!(button->type == 0 || button->type == EV_KEY ||
+		      button->type == EV_SW)) {
+			dev_err(dev, "only supports buttons or switches\n");
+			error = -EINVAL;
+			goto out;
+		}
+
+		if (button->irq) {
+			dev_err(dev, "skipping button %s (only gpio buttons supported)\n",
+				button->desc);
+			bdata->b = &pdata->buttons[i];
+			continue;
+		}
+
+		if (gpio_is_valid(button->gpio)) {
+			/* legacy platform data... but is it the lookup table? */
+			bdata->gpiod = devm_gpiod_get_index(dev, desc, i,
+							    GPIOD_IN);
+			if (IS_ERR(bdata->gpiod)) {
+				/* or the legacy (button->gpio is good) way? */
+				error = devm_gpio_request_one(dev,
+					button->gpio, GPIOF_IN | (
+					button->active_low ? GPIOF_ACTIVE_LOW :
+					0), desc);
+				if (error) {
+					if (error != -EPROBE_DEFER) {
+						dev_err(dev, "unable to claim gpio %d, err=%d\n",
+							button->gpio, error);
+					}
+					goto out;
+				}
+
+				bdata->gpiod = gpio_to_desc(button->gpio);
+			}
+		} else {
+			/* Device-tree */
+			struct device_node *child =
+				of_get_next_child(dev->of_node, prev);
+
+			bdata->gpiod = devm_fwnode_gpiod_get(dev,
+				of_fwnode_handle(child), NULL, GPIOD_IN,
+				desc);
+
+			prev = child;
+		}
+
+		if (IS_ERR_OR_NULL(bdata->gpiod)) {
+			error = IS_ERR(bdata->gpiod) ? PTR_ERR(bdata->gpiod) :
+				-EINVAL;
+			goto out;
+		}
+
+		bdata->can_sleep = gpiod_cansleep(bdata->gpiod);
+		bdata->last_state = -1; /* Unknown state on boot */
+
+		if (bdev->polled) {
+			bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
+							pdata->poll_interval);
+		} else {
+			/* bdata->threshold = 0; already initialized */
+
+			if (button->debounce_interval) {
+				error = gpiod_set_debounce(bdata->gpiod,
+					button->debounce_interval * 1000);
+				/*
+				 * use timer if gpiolib doesn't provide
+				 * debounce.
+				 */
+				if (error < 0) {
+					bdata->software_debounce =
+						button->debounce_interval;
+				}
+			}
+		}
+
+		bdata->b = &pdata->buttons[i];
+	}
+
+	bdev->dev = &pdev->dev;
+	bdev->pdata = pdata;
+	platform_set_drvdata(pdev, bdev);
+
+	*_bdev = bdev;
+	error = 0;
+
+out:
+	of_node_put(prev);
+	return error;
+}
+
+static int gpio_keys_probe(struct platform_device *pdev)
+{
+	struct gpio_keys_platform_data *pdata;
+	struct gpio_keys_button_dev *bdev;
+	int ret, i;
+
+	ret = gpio_keys_button_probe(pdev, &bdev, 0);
+	if (ret)
+		return ret;
+
+	pdata = bdev->pdata;
+	for (i = 0; i < pdata->nbuttons; i++) {
+		const struct gpio_keys_button *button = &pdata->buttons[i];
+		struct gpio_keys_button_data *bdata = &bdev->data[i];
+		unsigned long irqflags = IRQF_ONESHOT;
+
+		INIT_DELAYED_WORK(&bdata->work, gpio_keys_irq_work_func);
+
+		if (!button->irq) {
+			bdata->irq = gpiod_to_irq(bdata->gpiod);
+			if (bdata->irq < 0) {
+				dev_err(&pdev->dev, "failed to get irq for gpio:%d\n",
+					button->gpio);
+				continue;
+			}
+
+			irqflags |= IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
+		} else {
+			bdata->irq = button->irq;
+		}
+
+		schedule_delayed_work(&bdata->work,
+				      msecs_to_jiffies(bdata->software_debounce));
+
+		ret = devm_request_threaded_irq(&pdev->dev,
+			bdata->irq, NULL, button_handle_irq,
+			irqflags, dev_name(&pdev->dev), bdata);
+		if (ret < 0) {
+			bdata->irq = 0;
+			dev_err(&pdev->dev, "failed to request irq:%d for gpio:%d\n",
+				bdata->irq, button->gpio);
+			continue;
+		} else {
+			dev_dbg(&pdev->dev, "gpio:%d has irq:%d\n",
+				button->gpio, bdata->irq);
+		}
+	}
+
+	return 0;
+}
+
+static int gpio_keys_polled_probe(struct platform_device *pdev)
+{
+	struct gpio_keys_platform_data *pdata;
+	struct gpio_keys_button_dev *bdev;
+	int ret;
+
+	ret = gpio_keys_button_probe(pdev, &bdev, 1);
+	if (ret)
+		return ret;
+
+	INIT_DELAYED_WORK(&bdev->work, gpio_keys_polled_poll);
+
+	pdata = bdev->pdata;
+	if (pdata->enable)
+		pdata->enable(bdev->dev);
+
+	gpio_keys_polled_queue_work(bdev);
+
+	return ret;
+}
+
+static void gpio_keys_irq_close(struct gpio_keys_button_dev *bdev)
+{
+	struct gpio_keys_platform_data *pdata = bdev->pdata;
+	size_t i;
+
+	for (i = 0; i < pdata->nbuttons; i++) {
+		struct gpio_keys_button_data *bdata = &bdev->data[i];
+
+		disable_irq(bdata->irq);
+		cancel_delayed_work_sync(&bdata->work);
+	}
+}
+
+static int gpio_keys_remove(struct platform_device *pdev)
+{
+	struct gpio_keys_button_dev *bdev = platform_get_drvdata(pdev);
+
+	platform_set_drvdata(pdev, NULL);
+
+	if (bdev->polled)
+		gpio_keys_polled_close(bdev);
+	else
+		gpio_keys_irq_close(bdev);
+
+	return 0;
+}
+
+static struct platform_driver gpio_keys_driver = {
+	.probe	= gpio_keys_probe,
+	.remove	= gpio_keys_remove,
+	.driver	= {
+		.name	= "gpio-keys",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(gpio_keys_of_match),
+	},
+};
+
+static struct platform_driver gpio_keys_polled_driver = {
+	.probe	= gpio_keys_polled_probe,
+	.remove	= gpio_keys_remove,
+	.driver	= {
+		.name	= "gpio-keys-polled",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(gpio_keys_polled_of_match),
+	},
+};
+
+static int __init gpio_button_init(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&gpio_keys_driver);
+	if (ret)
+		return ret;
+
+	ret = platform_driver_register(&gpio_keys_polled_driver);
+	if (ret)
+		platform_driver_unregister(&gpio_keys_driver);
+
+	return ret;
+}
+
+static void __exit gpio_button_exit(void)
+{
+	platform_driver_unregister(&gpio_keys_driver);
+	platform_driver_unregister(&gpio_keys_polled_driver);
+}
+
+module_init(gpio_button_init);
+module_exit(gpio_button_exit);
+
+MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
+MODULE_AUTHOR("Felix Fietkau <nbd@nbd.name>");
+MODULE_DESCRIPTION("Polled GPIO Buttons hotplug driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRV_NAME);