Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1043 insertions, 0 deletions

diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
new file mode 100644
index 000000000..492a971b9
--- /dev/null
+++ b/drivers/input/keyboard/gpio_keys.c
@@ -0,0 +1,1043 @@
+/*
+ * Driver for keys on GPIO lines capable of generating interrupts.
+ *
+ * Copyright 2005 Phil Blundell
+ * Copyright 2010, 2011 David Jander <david@protonic.nl>
+ *
+ * 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/init.h>
+#include <linux/fs.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/sched.h>
+#include <linux/pm.h>
+#include <linux/slab.h>
+#include <linux/sysctl.h>
+#include <linux/proc_fs.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/gpio_keys.h>
+#include <linux/workqueue.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/spinlock.h>
+#include <dt-bindings/input/gpio-keys.h>
+
+struct gpio_button_data {
+	const struct gpio_keys_button *button;
+	struct input_dev *input;
+	struct gpio_desc *gpiod;
+
+	unsigned short *code;
+
+	struct timer_list release_timer;
+	unsigned int release_delay;	/* in msecs, for IRQ-only buttons */
+
+	struct delayed_work work;
+	unsigned int software_debounce;	/* in msecs, for GPIO-driven buttons */
+
+	unsigned int irq;
+	unsigned int wakeup_trigger_type;
+	spinlock_t lock;
+	bool disabled;
+	bool key_pressed;
+	bool suspended;
+};
+
+struct gpio_keys_drvdata {
+	const struct gpio_keys_platform_data *pdata;
+	struct input_dev *input;
+	struct mutex disable_lock;
+	unsigned short *keymap;
+	struct gpio_button_data data[0];
+};
+
+/*
+ * SYSFS interface for enabling/disabling keys and switches:
+ *
+ * There are 4 attributes under /sys/devices/platform/gpio-keys/
+ *	keys [ro]              - bitmap of keys (EV_KEY) which can be
+ *	                         disabled
+ *	switches [ro]          - bitmap of switches (EV_SW) which can be
+ *	                         disabled
+ *	disabled_keys [rw]     - bitmap of keys currently disabled
+ *	disabled_switches [rw] - bitmap of switches currently disabled
+ *
+ * Userland can change these values and hence disable event generation
+ * for each key (or switch). Disabling a key means its interrupt line
+ * is disabled.
+ *
+ * For example, if we have following switches set up as gpio-keys:
+ *	SW_DOCK = 5
+ *	SW_CAMERA_LENS_COVER = 9
+ *	SW_KEYPAD_SLIDE = 10
+ *	SW_FRONT_PROXIMITY = 11
+ * This is read from switches:
+ *	11-9,5
+ * Next we want to disable proximity (11) and dock (5), we write:
+ *	11,5
+ * to file disabled_switches. Now proximity and dock IRQs are disabled.
+ * This can be verified by reading the file disabled_switches:
+ *	11,5
+ * If we now want to enable proximity (11) switch we write:
+ *	5
+ * to disabled_switches.
+ *
+ * We can disable only those keys which don't allow sharing the irq.
+ */
+
+/**
+ * get_n_events_by_type() - returns maximum number of events per @type
+ * @type: type of button (%EV_KEY, %EV_SW)
+ *
+ * Return value of this function can be used to allocate bitmap
+ * large enough to hold all bits for given type.
+ */
+static int get_n_events_by_type(int type)
+{
+	BUG_ON(type != EV_SW && type != EV_KEY);
+
+	return (type == EV_KEY) ? KEY_CNT : SW_CNT;
+}
+
+/**
+ * get_bm_events_by_type() - returns bitmap of supported events per @type
+ * @input: input device from which bitmap is retrieved
+ * @type: type of button (%EV_KEY, %EV_SW)
+ *
+ * Return value of this function can be used to allocate bitmap
+ * large enough to hold all bits for given type.
+ */
+static const unsigned long *get_bm_events_by_type(struct input_dev *dev,
+						  int type)
+{
+	BUG_ON(type != EV_SW && type != EV_KEY);
+
+	return (type == EV_KEY) ? dev->keybit : dev->swbit;
+}
+
+/**
+ * gpio_keys_disable_button() - disables given GPIO button
+ * @bdata: button data for button to be disabled
+ *
+ * Disables button pointed by @bdata. This is done by masking
+ * IRQ line. After this function is called, button won't generate
+ * input events anymore. Note that one can only disable buttons
+ * that don't share IRQs.
+ *
+ * Make sure that @bdata->disable_lock is locked when entering
+ * this function to avoid races when concurrent threads are
+ * disabling buttons at the same time.
+ */
+static void gpio_keys_disable_button(struct gpio_button_data *bdata)
+{
+	if (!bdata->disabled) {
+		/*
+		 * Disable IRQ and associated timer/work structure.
+		 */
+		disable_irq(bdata->irq);
+
+		if (bdata->gpiod)
+			cancel_delayed_work_sync(&bdata->work);
+		else
+			del_timer_sync(&bdata->release_timer);
+
+		bdata->disabled = true;
+	}
+}
+
+/**
+ * gpio_keys_enable_button() - enables given GPIO button
+ * @bdata: button data for button to be disabled
+ *
+ * Enables given button pointed by @bdata.
+ *
+ * Make sure that @bdata->disable_lock is locked when entering
+ * this function to avoid races with concurrent threads trying
+ * to enable the same button at the same time.
+ */
+static void gpio_keys_enable_button(struct gpio_button_data *bdata)
+{
+	if (bdata->disabled) {
+		enable_irq(bdata->irq);
+		bdata->disabled = false;
+	}
+}
+
+/**
+ * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons
+ * @ddata: pointer to drvdata
+ * @buf: buffer where stringified bitmap is written
+ * @type: button type (%EV_KEY, %EV_SW)
+ * @only_disabled: does caller want only those buttons that are
+ *                 currently disabled or all buttons that can be
+ *                 disabled
+ *
+ * This function writes buttons that can be disabled to @buf. If
+ * @only_disabled is true, then @buf contains only those buttons
+ * that are currently disabled. Returns 0 on success or negative
+ * errno on failure.
+ */
+static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata,
+					  char *buf, unsigned int type,
+					  bool only_disabled)
+{
+	int n_events = get_n_events_by_type(type);
+	unsigned long *bits;
+	ssize_t ret;
+	int i;
+
+	bits = bitmap_zalloc(n_events, GFP_KERNEL);
+	if (!bits)
+		return -ENOMEM;
+
+	for (i = 0; i < ddata->pdata->nbuttons; i++) {
+		struct gpio_button_data *bdata = &ddata->data[i];
+
+		if (bdata->button->type != type)
+			continue;
+
+		if (only_disabled && !bdata->disabled)
+			continue;
+
+		__set_bit(*bdata->code, bits);
+	}
+
+	ret = scnprintf(buf, PAGE_SIZE - 1, "%*pbl", n_events, bits);
+	buf[ret++] = '\n';
+	buf[ret] = '\0';
+
+	bitmap_free(bits);
+
+	return ret;
+}
+
+/**
+ * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap
+ * @ddata: pointer to drvdata
+ * @buf: buffer from userspace that contains stringified bitmap
+ * @type: button type (%EV_KEY, %EV_SW)
+ *
+ * This function parses stringified bitmap from @buf and disables/enables
+ * GPIO buttons accordingly. Returns 0 on success and negative error
+ * on failure.
+ */
+static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata,
+					   const char *buf, unsigned int type)
+{
+	int n_events = get_n_events_by_type(type);
+	const unsigned long *bitmap = get_bm_events_by_type(ddata->input, type);
+	unsigned long *bits;
+	ssize_t error;
+	int i;
+
+	bits = bitmap_zalloc(n_events, GFP_KERNEL);
+	if (!bits)
+		return -ENOMEM;
+
+	error = bitmap_parselist(buf, bits, n_events);
+	if (error)
+		goto out;
+
+	/* First validate */
+	if (!bitmap_subset(bits, bitmap, n_events)) {
+		error = -EINVAL;
+		goto out;
+	}
+
+	for (i = 0; i < ddata->pdata->nbuttons; i++) {
+		struct gpio_button_data *bdata = &ddata->data[i];
+
+		if (bdata->button->type != type)
+			continue;
+
+		if (test_bit(*bdata->code, bits) &&
+		    !bdata->button->can_disable) {
+			error = -EINVAL;
+			goto out;
+		}
+	}
+
+	mutex_lock(&ddata->disable_lock);
+
+	for (i = 0; i < ddata->pdata->nbuttons; i++) {
+		struct gpio_button_data *bdata = &ddata->data[i];
+
+		if (bdata->button->type != type)
+			continue;
+
+		if (test_bit(*bdata->code, bits))
+			gpio_keys_disable_button(bdata);
+		else
+			gpio_keys_enable_button(bdata);
+	}
+
+	mutex_unlock(&ddata->disable_lock);
+
+out:
+	bitmap_free(bits);
+	return error;
+}
+
+#define ATTR_SHOW_FN(name, type, only_disabled)				\
+static ssize_t gpio_keys_show_##name(struct device *dev,		\
+				     struct device_attribute *attr,	\
+				     char *buf)				\
+{									\
+	struct platform_device *pdev = to_platform_device(dev);		\
+	struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);	\
+									\
+	return gpio_keys_attr_show_helper(ddata, buf,			\
+					  type, only_disabled);		\
+}
+
+ATTR_SHOW_FN(keys, EV_KEY, false);
+ATTR_SHOW_FN(switches, EV_SW, false);
+ATTR_SHOW_FN(disabled_keys, EV_KEY, true);
+ATTR_SHOW_FN(disabled_switches, EV_SW, true);
+
+/*
+ * ATTRIBUTES:
+ *
+ * /sys/devices/platform/gpio-keys/keys [ro]
+ * /sys/devices/platform/gpio-keys/switches [ro]
+ */
+static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL);
+static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL);
+
+#define ATTR_STORE_FN(name, type)					\
+static ssize_t gpio_keys_store_##name(struct device *dev,		\
+				      struct device_attribute *attr,	\
+				      const char *buf,			\
+				      size_t count)			\
+{									\
+	struct platform_device *pdev = to_platform_device(dev);		\
+	struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);	\
+	ssize_t error;							\
+									\
+	error = gpio_keys_attr_store_helper(ddata, buf, type);		\
+	if (error)							\
+		return error;						\
+									\
+	return count;							\
+}
+
+ATTR_STORE_FN(disabled_keys, EV_KEY);
+ATTR_STORE_FN(disabled_switches, EV_SW);
+
+/*
+ * ATTRIBUTES:
+ *
+ * /sys/devices/platform/gpio-keys/disabled_keys [rw]
+ * /sys/devices/platform/gpio-keys/disables_switches [rw]
+ */
+static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO,
+		   gpio_keys_show_disabled_keys,
+		   gpio_keys_store_disabled_keys);
+static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO,
+		   gpio_keys_show_disabled_switches,
+		   gpio_keys_store_disabled_switches);
+
+static struct attribute *gpio_keys_attrs[] = {
+	&dev_attr_keys.attr,
+	&dev_attr_switches.attr,
+	&dev_attr_disabled_keys.attr,
+	&dev_attr_disabled_switches.attr,
+	NULL,
+};
+
+static const struct attribute_group gpio_keys_attr_group = {
+	.attrs = gpio_keys_attrs,
+};
+
+static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata)
+{
+	const struct gpio_keys_button *button = bdata->button;
+	struct input_dev *input = bdata->input;
+	unsigned int type = button->type ?: EV_KEY;
+	int state;
+
+	state = gpiod_get_value_cansleep(bdata->gpiod);
+	if (state < 0) {
+		dev_err(input->dev.parent,
+			"failed to get gpio state: %d\n", state);
+		return;
+	}
+
+	if (type == EV_ABS) {
+		if (state)
+			input_event(input, type, button->code, button->value);
+	} else {
+		input_event(input, type, *bdata->code, state);
+	}
+	input_sync(input);
+}
+
+static void gpio_keys_gpio_work_func(struct work_struct *work)
+{
+	struct gpio_button_data *bdata =
+		container_of(work, struct gpio_button_data, work.work);
+
+	gpio_keys_gpio_report_event(bdata);
+
+	if (bdata->button->wakeup)
+		pm_relax(bdata->input->dev.parent);
+}
+
+static irqreturn_t gpio_keys_gpio_isr(int irq, void *dev_id)
+{
+	struct gpio_button_data *bdata = dev_id;
+
+	BUG_ON(irq != bdata->irq);
+
+	if (bdata->button->wakeup) {
+		const struct gpio_keys_button *button = bdata->button;
+
+		pm_stay_awake(bdata->input->dev.parent);
+		if (bdata->suspended  &&
+		    (button->type == 0 || button->type == EV_KEY)) {
+			/*
+			 * Simulate wakeup key press in case the key has
+			 * already released by the time we got interrupt
+			 * handler to run.
+			 */
+			input_report_key(bdata->input, button->code, 1);
+		}
+	}
+
+	mod_delayed_work(system_wq,
+			 &bdata->work,
+			 msecs_to_jiffies(bdata->software_debounce));
+
+	return IRQ_HANDLED;
+}
+
+static void gpio_keys_irq_timer(struct timer_list *t)
+{
+	struct gpio_button_data *bdata = from_timer(bdata, t, release_timer);
+	struct input_dev *input = bdata->input;
+	unsigned long flags;
+
+	spin_lock_irqsave(&bdata->lock, flags);
+	if (bdata->key_pressed) {
+		input_event(input, EV_KEY, *bdata->code, 0);
+		input_sync(input);
+		bdata->key_pressed = false;
+	}
+	spin_unlock_irqrestore(&bdata->lock, flags);
+}
+
+static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id)
+{
+	struct gpio_button_data *bdata = dev_id;
+	struct input_dev *input = bdata->input;
+	unsigned long flags;
+
+	BUG_ON(irq != bdata->irq);
+
+	spin_lock_irqsave(&bdata->lock, flags);
+
+	if (!bdata->key_pressed) {
+		if (bdata->button->wakeup)
+			pm_wakeup_event(bdata->input->dev.parent, 0);
+
+		input_event(input, EV_KEY, *bdata->code, 1);
+		input_sync(input);
+
+		if (!bdata->release_delay) {
+			input_event(input, EV_KEY, *bdata->code, 0);
+			input_sync(input);
+			goto out;
+		}
+
+		bdata->key_pressed = true;
+	}
+
+	if (bdata->release_delay)
+		mod_timer(&bdata->release_timer,
+			jiffies + msecs_to_jiffies(bdata->release_delay));
+out:
+	spin_unlock_irqrestore(&bdata->lock, flags);
+	return IRQ_HANDLED;
+}
+
+static void gpio_keys_quiesce_key(void *data)
+{
+	struct gpio_button_data *bdata = data;
+
+	if (bdata->gpiod)
+		cancel_delayed_work_sync(&bdata->work);
+	else
+		del_timer_sync(&bdata->release_timer);
+}
+
+static int gpio_keys_setup_key(struct platform_device *pdev,
+				struct input_dev *input,
+				struct gpio_keys_drvdata *ddata,
+				const struct gpio_keys_button *button,
+				int idx,
+				struct fwnode_handle *child)
+{
+	const char *desc = button->desc ? button->desc : "gpio_keys";
+	struct device *dev = &pdev->dev;
+	struct gpio_button_data *bdata = &ddata->data[idx];
+	irq_handler_t isr;
+	unsigned long irqflags;
+	int irq;
+	int error;
+
+	bdata->input = input;
+	bdata->button = button;
+	spin_lock_init(&bdata->lock);
+
+	if (child) {
+		bdata->gpiod = devm_fwnode_get_gpiod_from_child(dev, NULL,
+								child,
+								GPIOD_IN,
+								desc);
+		if (IS_ERR(bdata->gpiod)) {
+			error = PTR_ERR(bdata->gpiod);
+			if (error == -ENOENT) {
+				/*
+				 * GPIO is optional, we may be dealing with
+				 * purely interrupt-driven setup.
+				 */
+				bdata->gpiod = NULL;
+			} else {
+				if (error != -EPROBE_DEFER)
+					dev_err(dev, "failed to get gpio: %d\n",
+						error);
+				return error;
+			}
+		}
+	} else if (gpio_is_valid(button->gpio)) {
+		/*
+		 * Legacy GPIO number, so request the GPIO here and
+		 * convert it to descriptor.
+		 */
+		unsigned flags = GPIOF_IN;
+
+		if (button->active_low)
+			flags |= GPIOF_ACTIVE_LOW;
+
+		error = devm_gpio_request_one(dev, button->gpio, flags, desc);
+		if (error < 0) {
+			dev_err(dev, "Failed to request GPIO %d, error %d\n",
+				button->gpio, error);
+			return error;
+		}
+
+		bdata->gpiod = gpio_to_desc(button->gpio);
+		if (!bdata->gpiod)
+			return -EINVAL;
+	}
+
+	if (bdata->gpiod) {
+		bool active_low = gpiod_is_active_low(bdata->gpiod);
+
+		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;
+		}
+
+		if (button->irq) {
+			bdata->irq = button->irq;
+		} else {
+			irq = gpiod_to_irq(bdata->gpiod);
+			if (irq < 0) {
+				error = irq;
+				dev_err(dev,
+					"Unable to get irq number for GPIO %d, error %d\n",
+					button->gpio, error);
+				return error;
+			}
+			bdata->irq = irq;
+		}
+
+		INIT_DELAYED_WORK(&bdata->work, gpio_keys_gpio_work_func);
+
+		isr = gpio_keys_gpio_isr;
+		irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
+
+		switch (button->wakeup_event_action) {
+		case EV_ACT_ASSERTED:
+			bdata->wakeup_trigger_type = active_low ?
+				IRQ_TYPE_EDGE_FALLING : IRQ_TYPE_EDGE_RISING;
+			break;
+		case EV_ACT_DEASSERTED:
+			bdata->wakeup_trigger_type = active_low ?
+				IRQ_TYPE_EDGE_RISING : IRQ_TYPE_EDGE_FALLING;
+			break;
+		case EV_ACT_ANY:
+			/* fall through */
+		default:
+			/*
+			 * For other cases, we are OK letting suspend/resume
+			 * not reconfigure the trigger type.
+			 */
+			break;
+		}
+	} else {
+		if (!button->irq) {
+			dev_err(dev, "Found button without gpio or irq\n");
+			return -EINVAL;
+		}
+
+		bdata->irq = button->irq;
+
+		if (button->type && button->type != EV_KEY) {
+			dev_err(dev, "Only EV_KEY allowed for IRQ buttons.\n");
+			return -EINVAL;
+		}
+
+		bdata->release_delay = button->debounce_interval;
+		timer_setup(&bdata->release_timer, gpio_keys_irq_timer, 0);
+
+		isr = gpio_keys_irq_isr;
+		irqflags = 0;
+
+		/*
+		 * For IRQ buttons, there is no interrupt for release.
+		 * So we don't need to reconfigure the trigger type for wakeup.
+		 */
+	}
+
+	bdata->code = &ddata->keymap[idx];
+	*bdata->code = button->code;
+	input_set_capability(input, button->type ?: EV_KEY, *bdata->code);
+
+	/*
+	 * Install custom action to cancel release timer and
+	 * workqueue item.
+	 */
+	error = devm_add_action(dev, gpio_keys_quiesce_key, bdata);
+	if (error) {
+		dev_err(dev, "failed to register quiesce action, error: %d\n",
+			error);
+		return error;
+	}
+
+	/*
+	 * If platform has specified that the button can be disabled,
+	 * we don't want it to share the interrupt line.
+	 */
+	if (!button->can_disable)
+		irqflags |= IRQF_SHARED;
+
+	error = devm_request_any_context_irq(dev, bdata->irq, isr, irqflags,
+					     desc, bdata);
+	if (error < 0) {
+		dev_err(dev, "Unable to claim irq %d; error %d\n",
+			bdata->irq, error);
+		return error;
+	}
+
+	return 0;
+}
+
+static void gpio_keys_report_state(struct gpio_keys_drvdata *ddata)
+{
+	struct input_dev *input = ddata->input;
+	int i;
+
+	for (i = 0; i < ddata->pdata->nbuttons; i++) {
+		struct gpio_button_data *bdata = &ddata->data[i];
+		if (bdata->gpiod)
+			gpio_keys_gpio_report_event(bdata);
+	}
+	input_sync(input);
+}
+
+static int gpio_keys_open(struct input_dev *input)
+{
+	struct gpio_keys_drvdata *ddata = input_get_drvdata(input);
+	const struct gpio_keys_platform_data *pdata = ddata->pdata;
+	int error;
+
+	if (pdata->enable) {
+		error = pdata->enable(input->dev.parent);
+		if (error)
+			return error;
+	}
+
+	/* Report current state of buttons that are connected to GPIOs */
+	gpio_keys_report_state(ddata);
+
+	return 0;
+}
+
+static void gpio_keys_close(struct input_dev *input)
+{
+	struct gpio_keys_drvdata *ddata = input_get_drvdata(input);
+	const struct gpio_keys_platform_data *pdata = ddata->pdata;
+
+	if (pdata->disable)
+		pdata->disable(input->dev.parent);
+}
+
+/*
+ * Handlers for alternative sources of platform_data
+ */
+
+/*
+ * Translate properties into platform_data
+ */
+static struct gpio_keys_platform_data *
+gpio_keys_get_devtree_pdata(struct device *dev)
+{
+	struct gpio_keys_platform_data *pdata;
+	struct gpio_keys_button *button;
+	struct fwnode_handle *child;
+	int nbuttons;
+
+	nbuttons = device_get_child_node_count(dev);
+	if (nbuttons == 0)
+		return ERR_PTR(-ENODEV);
+
+	pdata = devm_kzalloc(dev,
+			     sizeof(*pdata) + nbuttons * sizeof(*button),
+			     GFP_KERNEL);
+	if (!pdata)
+		return ERR_PTR(-ENOMEM);
+
+	button = (struct gpio_keys_button *)(pdata + 1);
+
+	pdata->buttons = button;
+	pdata->nbuttons = nbuttons;
+
+	pdata->rep = device_property_read_bool(dev, "autorepeat");
+
+	device_property_read_string(dev, "label", &pdata->name);
+
+	device_for_each_child_node(dev, child) {
+		if (is_of_node(child))
+			button->irq =
+				irq_of_parse_and_map(to_of_node(child), 0);
+
+		if (fwnode_property_read_u32(child, "linux,code",
+					     &button->code)) {
+			dev_err(dev, "Button without keycode\n");
+			fwnode_handle_put(child);
+			return ERR_PTR(-EINVAL);
+		}
+
+		fwnode_property_read_string(child, "label", &button->desc);
+
+		if (fwnode_property_read_u32(child, "linux,input-type",
+					     &button->type))
+			button->type = EV_KEY;
+
+		button->wakeup =
+			fwnode_property_read_bool(child, "wakeup-source") ||
+			/* legacy name */
+			fwnode_property_read_bool(child, "gpio-key,wakeup");
+
+		fwnode_property_read_u32(child, "wakeup-event-action",
+					 &button->wakeup_event_action);
+
+		button->can_disable =
+			fwnode_property_read_bool(child, "linux,can-disable");
+
+		if (fwnode_property_read_u32(child, "debounce-interval",
+					 &button->debounce_interval))
+			button->debounce_interval = 5;
+
+		button++;
+	}
+
+	return pdata;
+}
+
+static const struct of_device_id gpio_keys_of_match[] = {
+	{ .compatible = "gpio-keys", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
+
+static int gpio_keys_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev);
+	struct fwnode_handle *child = NULL;
+	struct gpio_keys_drvdata *ddata;
+	struct input_dev *input;
+	size_t size;
+	int i, error;
+	int wakeup = 0;
+
+	if (!pdata) {
+		pdata = gpio_keys_get_devtree_pdata(dev);
+		if (IS_ERR(pdata))
+			return PTR_ERR(pdata);
+	}
+
+	size = sizeof(struct gpio_keys_drvdata) +
+			pdata->nbuttons * sizeof(struct gpio_button_data);
+	ddata = devm_kzalloc(dev, size, GFP_KERNEL);
+	if (!ddata) {
+		dev_err(dev, "failed to allocate state\n");
+		return -ENOMEM;
+	}
+
+	ddata->keymap = devm_kcalloc(dev,
+				     pdata->nbuttons, sizeof(ddata->keymap[0]),
+				     GFP_KERNEL);
+	if (!ddata->keymap)
+		return -ENOMEM;
+
+	input = devm_input_allocate_device(dev);
+	if (!input) {
+		dev_err(dev, "failed to allocate input device\n");
+		return -ENOMEM;
+	}
+
+	ddata->pdata = pdata;
+	ddata->input = input;
+	mutex_init(&ddata->disable_lock);
+
+	platform_set_drvdata(pdev, ddata);
+	input_set_drvdata(input, ddata);
+
+	input->name = pdata->name ? : pdev->name;
+	input->phys = "gpio-keys/input0";
+	input->dev.parent = dev;
+	input->open = gpio_keys_open;
+	input->close = gpio_keys_close;
+
+	input->id.bustype = BUS_HOST;
+	input->id.vendor = 0x0001;
+	input->id.product = 0x0001;
+	input->id.version = 0x0100;
+
+	input->keycode = ddata->keymap;
+	input->keycodesize = sizeof(ddata->keymap[0]);
+	input->keycodemax = pdata->nbuttons;
+
+	/* Enable auto repeat feature of Linux input subsystem */
+	if (pdata->rep)
+		__set_bit(EV_REP, input->evbit);
+
+	for (i = 0; i < pdata->nbuttons; i++) {
+		const struct gpio_keys_button *button = &pdata->buttons[i];
+
+		if (!dev_get_platdata(dev)) {
+			child = device_get_next_child_node(dev, child);
+			if (!child) {
+				dev_err(dev,
+					"missing child device node for entry %d\n",
+					i);
+				return -EINVAL;
+			}
+		}
+
+		error = gpio_keys_setup_key(pdev, input, ddata,
+					    button, i, child);
+		if (error) {
+			fwnode_handle_put(child);
+			return error;
+		}
+
+		if (button->wakeup)
+			wakeup = 1;
+	}
+
+	fwnode_handle_put(child);
+
+	error = devm_device_add_group(dev, &gpio_keys_attr_group);
+	if (error) {
+		dev_err(dev, "Unable to export keys/switches, error: %d\n",
+			error);
+		return error;
+	}
+
+	error = input_register_device(input);
+	if (error) {
+		dev_err(dev, "Unable to register input device, error: %d\n",
+			error);
+		return error;
+	}
+
+	device_init_wakeup(dev, wakeup);
+
+	return 0;
+}
+
+static int __maybe_unused
+gpio_keys_button_enable_wakeup(struct gpio_button_data *bdata)
+{
+	int error;
+
+	error = enable_irq_wake(bdata->irq);
+	if (error) {
+		dev_err(bdata->input->dev.parent,
+			"failed to configure IRQ %d as wakeup source: %d\n",
+			bdata->irq, error);
+		return error;
+	}
+
+	if (bdata->wakeup_trigger_type) {
+		error = irq_set_irq_type(bdata->irq,
+					 bdata->wakeup_trigger_type);
+		if (error) {
+			dev_err(bdata->input->dev.parent,
+				"failed to set wakeup trigger %08x for IRQ %d: %d\n",
+				bdata->wakeup_trigger_type, bdata->irq, error);
+			disable_irq_wake(bdata->irq);
+			return error;
+		}
+	}
+
+	return 0;
+}
+
+static void __maybe_unused
+gpio_keys_button_disable_wakeup(struct gpio_button_data *bdata)
+{
+	int error;
+
+	/*
+	 * The trigger type is always both edges for gpio-based keys and we do
+	 * not support changing wakeup trigger for interrupt-based keys.
+	 */
+	if (bdata->wakeup_trigger_type) {
+		error = irq_set_irq_type(bdata->irq, IRQ_TYPE_EDGE_BOTH);
+		if (error)
+			dev_warn(bdata->input->dev.parent,
+				 "failed to restore interrupt trigger for IRQ %d: %d\n",
+				 bdata->irq, error);
+	}
+
+	error = disable_irq_wake(bdata->irq);
+	if (error)
+		dev_warn(bdata->input->dev.parent,
+			 "failed to disable IRQ %d as wake source: %d\n",
+			 bdata->irq, error);
+}
+
+static int __maybe_unused
+gpio_keys_enable_wakeup(struct gpio_keys_drvdata *ddata)
+{
+	struct gpio_button_data *bdata;
+	int error;
+	int i;
+
+	for (i = 0; i < ddata->pdata->nbuttons; i++) {
+		bdata = &ddata->data[i];
+		if (bdata->button->wakeup) {
+			error = gpio_keys_button_enable_wakeup(bdata);
+			if (error)
+				goto err_out;
+		}
+		bdata->suspended = true;
+	}
+
+	return 0;
+
+err_out:
+	while (i--) {
+		bdata = &ddata->data[i];
+		if (bdata->button->wakeup)
+			gpio_keys_button_disable_wakeup(bdata);
+		bdata->suspended = false;
+	}
+
+	return error;
+}
+
+static void __maybe_unused
+gpio_keys_disable_wakeup(struct gpio_keys_drvdata *ddata)
+{
+	struct gpio_button_data *bdata;
+	int i;
+
+	for (i = 0; i < ddata->pdata->nbuttons; i++) {
+		bdata = &ddata->data[i];
+		bdata->suspended = false;
+		if (irqd_is_wakeup_set(irq_get_irq_data(bdata->irq)))
+			gpio_keys_button_disable_wakeup(bdata);
+	}
+}
+
+static int __maybe_unused gpio_keys_suspend(struct device *dev)
+{
+	struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev);
+	struct input_dev *input = ddata->input;
+	int error;
+
+	if (device_may_wakeup(dev)) {
+		error = gpio_keys_enable_wakeup(ddata);
+		if (error)
+			return error;
+	} else {
+		mutex_lock(&input->mutex);
+		if (input->users)
+			gpio_keys_close(input);
+		mutex_unlock(&input->mutex);
+	}
+
+	return 0;
+}
+
+static int __maybe_unused gpio_keys_resume(struct device *dev)
+{
+	struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev);
+	struct input_dev *input = ddata->input;
+	int error = 0;
+
+	if (device_may_wakeup(dev)) {
+		gpio_keys_disable_wakeup(ddata);
+	} else {
+		mutex_lock(&input->mutex);
+		if (input->users)
+			error = gpio_keys_open(input);
+		mutex_unlock(&input->mutex);
+	}
+
+	if (error)
+		return error;
+
+	gpio_keys_report_state(ddata);
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume);
+
+static struct platform_driver gpio_keys_device_driver = {
+	.probe		= gpio_keys_probe,
+	.driver		= {
+		.name	= "gpio-keys",
+		.pm	= &gpio_keys_pm_ops,
+		.of_match_table = gpio_keys_of_match,
+	}
+};
+
+static int __init gpio_keys_init(void)
+{
+	return platform_driver_register(&gpio_keys_device_driver);
+}
+
+static void __exit gpio_keys_exit(void)
+{
+	platform_driver_unregister(&gpio_keys_device_driver);
+}
+
+late_initcall(gpio_keys_init);
+module_exit(gpio_keys_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>");
+MODULE_DESCRIPTION("Keyboard driver for GPIOs");
+MODULE_ALIAS("platform:gpio-keys");