[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / input / keyboard / gpio_keys.c

/*
 * Driver for keys on GPIO lines capable of generating interrupts.
 *
 * Copyright 2005 Phil Blundell
 *
 * 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>

struct gpio_button_data {
	struct gpio_keys_button *button;
	struct input_dev *input;
	struct timer_list timer;
	struct work_struct work;
	bool disabled;
};

struct gpio_keys_drvdata {
	struct input_dev *input;
	struct mutex disable_lock;
	unsigned int n_buttons;
	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 inline int get_n_events_by_type(int type)
{
	BUG_ON(type != EV_SW && type != EV_KEY);

	return (type == EV_KEY) ? KEY_CNT : SW_CNT;
}

/**
 * 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 possible debouncing timer.
		 */
		disable_irq(gpio_to_irq(bdata->button->gpio));
		if (bdata->button->debounce_interval)
			del_timer_sync(&bdata->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(gpio_to_irq(bdata->button->gpio));
		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 = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
	if (!bits)
		return -ENOMEM;

	for (i = 0; i < ddata->n_buttons; i++) {
		struct gpio_button_data *bdata = &ddata->data[i];

		if (bdata->button->type != type)
			continue;

		if (only_disabled && !bdata->disabled)
			continue;

		__set_bit(bdata->button->code, bits);
	}

	ret = bitmap_scnlistprintf(buf, PAGE_SIZE - 2, bits, n_events);
	buf[ret++] = '\n';
	buf[ret] = '\0';

	kfree(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 accordinly. 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);
	unsigned long *bits;
	ssize_t error;
	int i;

	bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
	if (!bits)
		return -ENOMEM;

	error = bitmap_parselist(buf, bits, n_events);
	if (error)
		goto out;

	/* First validate */
	for (i = 0; i < ddata->n_buttons; i++) {
		struct gpio_button_data *bdata = &ddata->data[i];

		if (bdata->button->type != type)
			continue;

		if (test_bit(bdata->button->code, bits) &&
		    !bdata->button->can_disable) {
			error = -EINVAL;
			goto out;
		}
	}

	mutex_lock(&ddata->disable_lock);

	for (i = 0; i < ddata->n_buttons; i++) {
		struct gpio_button_data *bdata = &ddata->data[i];

		if (bdata->button->type != type)
			continue;

		if (test_bit(bdata->button->code, bits))
			gpio_keys_disable_button(bdata);
		else
			gpio_keys_enable_button(bdata);
	}

	mutex_unlock(&ddata->disable_lock);

out:
	kfree(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 struct attribute_group gpio_keys_attr_group = {
	.attrs = gpio_keys_attrs,
};

static void gpio_keys_report_event(struct gpio_button_data *bdata)
{
	struct gpio_keys_button *button = bdata->button;
	struct input_dev *input = bdata->input;
	unsigned int type = button->type ?: EV_KEY;
	int state = (gpio_get_value(button->gpio) ? 1 : 0) ^ button->active_low;

	input_event(input, type, button->code, !!state);
	input_sync(input);
}

static void gpio_keys_work_func(struct work_struct *work)
{
	struct gpio_button_data *bdata =
		container_of(work, struct gpio_button_data, work);

	gpio_keys_report_event(bdata);
}

static void gpio_keys_timer(unsigned long _data)
{
	struct gpio_button_data *data = (struct gpio_button_data *)_data;

	schedule_work(&data->work);
}

static irqreturn_t gpio_keys_isr(int irq, void *dev_id)
{
	struct gpio_button_data *bdata = dev_id;
	struct gpio_keys_button *button = bdata->button;

	BUG_ON(irq != gpio_to_irq(button->gpio));

	if (button->debounce_interval)
		mod_timer(&bdata->timer,
			jiffies + msecs_to_jiffies(button->debounce_interval));
	else
		schedule_work(&bdata->work);

	return IRQ_HANDLED;
}

static int __devinit gpio_keys_setup_key(struct platform_device *pdev,
					 struct gpio_button_data *bdata,
					 struct gpio_keys_button *button)
{
	char *desc = button->desc ? button->desc : "gpio_keys";
	struct device *dev = &pdev->dev;
	unsigned long irqflags;
	int irq, error;

	setup_timer(&bdata->timer, gpio_keys_timer, (unsigned long)bdata);
	INIT_WORK(&bdata->work, gpio_keys_work_func);

	error = gpio_request(button->gpio, desc);
	if (error < 0) {
		dev_err(dev, "failed to request GPIO %d, error %d\n",
			button->gpio, error);
		goto fail2;
	}

	error = gpio_direction_input(button->gpio);
	if (error < 0) {
		dev_err(dev, "failed to configure"
			" direction for GPIO %d, error %d\n",
			button->gpio, error);
		goto fail3;
	}

	irq = gpio_to_irq(button->gpio);
	if (irq < 0) {
		error = irq;
		dev_err(dev, "Unable to get irq number for GPIO %d, error %d\n",
			button->gpio, error);
		goto fail3;
	}

	irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
	/*
	 * 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 = request_irq(irq, gpio_keys_isr, irqflags, desc, bdata);
	if (error) {
		dev_err(dev, "Unable to claim irq %d; error %d\n",
			irq, error);
		goto fail3;
	}

	return 0;

fail3:
	gpio_free(button->gpio);
fail2:
	return error;
}

static int __devinit gpio_keys_probe(struct platform_device *pdev)
{
	struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
	struct gpio_keys_drvdata *ddata;
	struct device *dev = &pdev->dev;
	struct input_dev *input;
	int i, error;
	int wakeup = 0;

	ddata = kzalloc(sizeof(struct gpio_keys_drvdata) +
			pdata->nbuttons * sizeof(struct gpio_button_data),
			GFP_KERNEL);
	input = input_allocate_device();
	if (!ddata || !input) {
		dev_err(dev, "failed to allocate state\n");
		error = -ENOMEM;
		goto fail1;
	}

	ddata->input = input;
	ddata->n_buttons = pdata->nbuttons;
	mutex_init(&ddata->disable_lock);

	platform_set_drvdata(pdev, ddata);

	input->name = pdev->name;
	input->phys = "gpio-keys/input0";
	input->dev.parent = &pdev->dev;

	input->id.bustype = BUS_HOST;
	input->id.vendor = 0x0001;
	input->id.product = 0x0001;
	input->id.version = 0x0100;

	/* Enable auto repeat feature of Linux input subsystem */
	if (pdata->rep)
		__set_bit(EV_REP, input->evbit);

	for (i = 0; i < pdata->nbuttons; i++) {
		struct gpio_keys_button *button = &pdata->buttons[i];
		struct gpio_button_data *bdata = &ddata->data[i];
		unsigned int type = button->type ?: EV_KEY;

		bdata->input = input;
		bdata->button = button;

		error = gpio_keys_setup_key(pdev, bdata, button);
		if (error)
			goto fail2;

		if (button->wakeup)
			wakeup = 1;

		input_set_capability(input, type, button->code);
	}

	error = sysfs_create_group(&pdev->dev.kobj, &gpio_keys_attr_group);
	if (error) {
		dev_err(dev, "Unable to export keys/switches, error: %d\n",
			error);
		goto fail2;
	}

	error = input_register_device(input);
	if (error) {
		dev_err(dev, "Unable to register input device, error: %d\n",
			error);
		goto fail3;
	}

	/* get current state of buttons */
	for (i = 0; i < pdata->nbuttons; i++)
		gpio_keys_report_event(&ddata->data[i]);
	input_sync(input);

	device_init_wakeup(&pdev->dev, wakeup);

	return 0;

 fail3:
	sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
 fail2:
	while (--i >= 0) {
		free_irq(gpio_to_irq(pdata->buttons[i].gpio), &ddata->data[i]);
		if (pdata->buttons[i].debounce_interval)
			del_timer_sync(&ddata->data[i].timer);
		cancel_work_sync(&ddata->data[i].work);
		gpio_free(pdata->buttons[i].gpio);
	}

	platform_set_drvdata(pdev, NULL);
 fail1:
	input_free_device(input);
	kfree(ddata);

	return error;
}

static int __devexit gpio_keys_remove(struct platform_device *pdev)
{
	struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
	struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
	struct input_dev *input = ddata->input;
	int i;

	sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);

	device_init_wakeup(&pdev->dev, 0);

	for (i = 0; i < pdata->nbuttons; i++) {
		int irq = gpio_to_irq(pdata->buttons[i].gpio);
		free_irq(irq, &ddata->data[i]);
		if (pdata->buttons[i].debounce_interval)
			del_timer_sync(&ddata->data[i].timer);
		cancel_work_sync(&ddata->data[i].work);
		gpio_free(pdata->buttons[i].gpio);
	}

	input_unregister_device(input);

	return 0;
}


#ifdef CONFIG_PM
static int gpio_keys_suspend(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
	int i;

	if (device_may_wakeup(&pdev->dev)) {
		for (i = 0; i < pdata->nbuttons; i++) {
			struct gpio_keys_button *button = &pdata->buttons[i];
			if (button->wakeup) {
				int irq = gpio_to_irq(button->gpio);
				enable_irq_wake(irq);
			}
		}
	}

	return 0;
}

static int gpio_keys_resume(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
	struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
	int i;

	for (i = 0; i < pdata->nbuttons; i++) {

		struct gpio_keys_button *button = &pdata->buttons[i];
		if (button->wakeup && device_may_wakeup(&pdev->dev)) {
			int irq = gpio_to_irq(button->gpio);
			disable_irq_wake(irq);
		}

		gpio_keys_report_event(&ddata->data[i]);
	}
	input_sync(ddata->input);

	return 0;
}

static const struct dev_pm_ops gpio_keys_pm_ops = {
	.suspend	= gpio_keys_suspend,
	.resume		= gpio_keys_resume,
};
#endif

static struct platform_driver gpio_keys_device_driver = {
	.probe		= gpio_keys_probe,
	.remove		= __devexit_p(gpio_keys_remove),
	.driver		= {
		.name	= "gpio-keys",
		.owner	= THIS_MODULE,
#ifdef CONFIG_PM
		.pm	= &gpio_keys_pm_ops,
#endif
	}
};

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);
}

module_init(gpio_keys_init);
module_exit(gpio_keys_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>");
MODULE_DESCRIPTION("Keyboard driver for CPU GPIOs");
MODULE_ALIAS("platform:gpio-keys");
Commit	Line	Data
78a56aab PB	1	/*
	2	* Driver for keys on GPIO lines capable of generating interrupts.
	3	*
	4	* Copyright 2005 Phil Blundell
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*/
	10
	11	#include <linux/module.h>
78a56aab PB	12
	13	#include <linux/init.h>
	14	#include <linux/fs.h>
	15	#include <linux/interrupt.h>
	16	#include <linux/irq.h>
	17	#include <linux/sched.h>
	18	#include <linux/pm.h>
5a0e3ad6	19	#include <linux/slab.h>
78a56aab PB	20	#include <linux/sysctl.h>
	21	#include <linux/proc_fs.h>
	22	#include <linux/delay.h>
	23	#include <linux/platform_device.h>
	24	#include <linux/input.h>
49015bee	25	#include <linux/gpio_keys.h>
da0d03fe	26	#include <linux/workqueue.h>
111bc59c	27	#include <linux/gpio.h>
78a56aab	28
a33466e3 DES	29	struct gpio_button_data {
	30	struct gpio_keys_button *button;
	31	struct input_dev *input;
ca865a77	32	struct timer_list timer;
da0d03fe	33	struct work_struct work;
9e3af04f	34	bool disabled;
a33466e3 DES	35	};
	36
	37	struct gpio_keys_drvdata {
	38	struct input_dev *input;
9e3af04f MW	39	struct mutex disable_lock;
9e3af04f MW	40	unsigned int n_buttons;
a33466e3 DES	41	struct gpio_button_data data[0];
	42	};
	43
9e3af04f MW	44	/*
	45	* SYSFS interface for enabling/disabling keys and switches:
	46	*
	47	* There are 4 attributes under /sys/devices/platform/gpio-keys/
	48	* keys [ro] - bitmap of keys (EV_KEY) which can be
	49	* disabled
	50	* switches [ro] - bitmap of switches (EV_SW) which can be
	51	* disabled
	52	* disabled_keys [rw] - bitmap of keys currently disabled
	53	* disabled_switches [rw] - bitmap of switches currently disabled
	54	*
	55	* Userland can change these values and hence disable event generation
	56	* for each key (or switch). Disabling a key means its interrupt line
	57	* is disabled.
	58	*
	59	* For example, if we have following switches set up as gpio-keys:
	60	* SW_DOCK = 5
	61	* SW_CAMERA_LENS_COVER = 9
	62	* SW_KEYPAD_SLIDE = 10
	63	* SW_FRONT_PROXIMITY = 11
	64	* This is read from switches:
	65	* 11-9,5
	66	* Next we want to disable proximity (11) and dock (5), we write:
	67	* 11,5
	68	* to file disabled_switches. Now proximity and dock IRQs are disabled.
	69	* This can be verified by reading the file disabled_switches:
	70	* 11,5
	71	* If we now want to enable proximity (11) switch we write:
	72	* 5
	73	* to disabled_switches.
	74	*
	75	* We can disable only those keys which don't allow sharing the irq.
	76	*/
	77
	78	/**
	79	* get_n_events_by_type() - returns maximum number of events per @type
	80	* @type: type of button (%EV_KEY, %EV_SW)
	81	*
	82	* Return value of this function can be used to allocate bitmap
	83	* large enough to hold all bits for given type.
	84	*/
	85	static inline int get_n_events_by_type(int type)
	86	{
	87	BUG_ON(type != EV_SW && type != EV_KEY);
	88
	89	return (type == EV_KEY) ? KEY_CNT : SW_CNT;
	90	}
	91
	92	/**
	93	* gpio_keys_disable_button() - disables given GPIO button
	94	* @bdata: button data for button to be disabled
	95	*
	96	* Disables button pointed by @bdata. This is done by masking
	97	* IRQ line. After this function is called, button won't generate
	98	* input events anymore. Note that one can only disable buttons
	99	* that don't share IRQs.
	100	*
	101	* Make sure that @bdata->disable_lock is locked when entering
	102	* this function to avoid races when concurrent threads are
	103	* disabling buttons at the same time.
	104	*/
	105	static void gpio_keys_disable_button(struct gpio_button_data *bdata)
	106	{
	107	if (!bdata->disabled) {
108	/*
109	* Disable IRQ and possible debouncing timer.
110	*/
111	disable_irq(gpio_to_irq(bdata->button->gpio));
112	if (bdata->button->debounce_interval)
113	del_timer_sync(&bdata->timer);
114
115	bdata->disabled = true;
116	}
117	}
118
119	/**
120	* gpio_keys_enable_button() - enables given GPIO button
121	* @bdata: button data for button to be disabled
122	*
123	* Enables given button pointed by @bdata.
124	*
125	* Make sure that @bdata->disable_lock is locked when entering
126	* this function to avoid races with concurrent threads trying
127	* to enable the same button at the same time.
128	*/
129	static void gpio_keys_enable_button(struct gpio_button_data *bdata)
130	{
131	if (bdata->disabled) {
132	enable_irq(gpio_to_irq(bdata->button->gpio));
133	bdata->disabled = false;
134	}
135	}
136
137	/**
138	* gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons
139	* @ddata: pointer to drvdata
140	* @buf: buffer where stringified bitmap is written
141	* @type: button type (%EV_KEY, %EV_SW)
142	* @only_disabled: does caller want only those buttons that are
143	* currently disabled or all buttons that can be
144	* disabled
145	*
146	* This function writes buttons that can be disabled to @buf. If
147	* @only_disabled is true, then @buf contains only those buttons
148	* that are currently disabled. Returns 0 on success or negative
149	* errno on failure.
150	*/
151	static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata,
152	char *buf, unsigned int type,
153	bool only_disabled)
154	{
155	int n_events = get_n_events_by_type(type);
156	unsigned long *bits;
157	ssize_t ret;
158	int i;
159
160	bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
161	if (!bits)
162	return -ENOMEM;
163
164	for (i = 0; i < ddata->n_buttons; i++) {
165	struct gpio_button_data *bdata = &ddata->data[i];
166
167	if (bdata->button->type != type)
168	continue;
169
170	if (only_disabled && !bdata->disabled)
171	continue;
172
173	__set_bit(bdata->button->code, bits);
174	}
175
176	ret = bitmap_scnlistprintf(buf, PAGE_SIZE - 2, bits, n_events);
177	buf[ret++] = '\n';
178	buf[ret] = '\0';
179
180	kfree(bits);
181
182	return ret;
183	}
184
185	/**
186	* gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap
187	* @ddata: pointer to drvdata
188	* @buf: buffer from userspace that contains stringified bitmap
189	* @type: button type (%EV_KEY, %EV_SW)
190	*
191	* This function parses stringified bitmap from @buf and disables/enables
192	* GPIO buttons accordinly. Returns 0 on success and negative error
193	* on failure.
194	*/
195	static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata,
196	const char *buf, unsigned int type)
197	{
198	int n_events = get_n_events_by_type(type);
199	unsigned long *bits;
200	ssize_t error;
201	int i;
202
203	bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
204	if (!bits)
205	return -ENOMEM;
206
207	error = bitmap_parselist(buf, bits, n_events);
208	if (error)
209	goto out;
210
211	/* First validate */
212	for (i = 0; i < ddata->n_buttons; i++) {
213	struct gpio_button_data *bdata = &ddata->data[i];
214
215	if (bdata->button->type != type)
216	continue;
217
218	if (test_bit(bdata->button->code, bits) &&
219	!bdata->button->can_disable) {
220	error = -EINVAL;
221	goto out;
222	}
223	}
224
225	mutex_lock(&ddata->disable_lock);
226
227	for (i = 0; i < ddata->n_buttons; i++) {
228	struct gpio_button_data *bdata = &ddata->data[i];
229
230	if (bdata->button->type != type)
231	continue;
232
233	if (test_bit(bdata->button->code, bits))
234	gpio_keys_disable_button(bdata);
235	else
236	gpio_keys_enable_button(bdata);
237	}
238
239	mutex_unlock(&ddata->disable_lock);
240
241	out:
242	kfree(bits);
243	return error;
244	}
245
246	#define ATTR_SHOW_FN(name, type, only_disabled) \
247	static ssize_t gpio_keys_show_##name(struct device *dev, \
248	struct device_attribute *attr, \
249	char *buf) \
250	{ \
251	struct platform_device *pdev = to_platform_device(dev); \
252	struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \
253	\
254	return gpio_keys_attr_show_helper(ddata, buf, \
255	type, only_disabled); \
256	}
257
258	ATTR_SHOW_FN(keys, EV_KEY, false);
259	ATTR_SHOW_FN(switches, EV_SW, false);
260	ATTR_SHOW_FN(disabled_keys, EV_KEY, true);
261	ATTR_SHOW_FN(disabled_switches, EV_SW, true);
262
263	/*
264	* ATTRIBUTES:
265	*
266	* /sys/devices/platform/gpio-keys/keys [ro]
267	* /sys/devices/platform/gpio-keys/switches [ro]
268	*/
269	static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL);
270	static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL);
271
272	#define ATTR_STORE_FN(name, type) \
273	static ssize_t gpio_keys_store_##name(struct device *dev, \
274	struct device_attribute *attr, \
275	const char *buf, \
276	size_t count) \
277	{ \
278	struct platform_device *pdev = to_platform_device(dev); \
279	struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \
280	ssize_t error; \
281	\
282	error = gpio_keys_attr_store_helper(ddata, buf, type); \
283	if (error) \
284	return error; \
285	\
286	return count; \
287	}
288
289	ATTR_STORE_FN(disabled_keys, EV_KEY);
290	ATTR_STORE_FN(disabled_switches, EV_SW);
291
292	/*
293	* ATTRIBUTES:
294	*
295	* /sys/devices/platform/gpio-keys/disabled_keys [rw]
296	* /sys/devices/platform/gpio-keys/disables_switches [rw]
297	*/
298	static DEVICE_ATTR(disabled_keys, S_IWUSR \| S_IRUGO,
299	gpio_keys_show_disabled_keys,
300	gpio_keys_store_disabled_keys);
301	static DEVICE_ATTR(disabled_switches, S_IWUSR \| S_IRUGO,
302	gpio_keys_show_disabled_switches,
303	gpio_keys_store_disabled_switches);
304
305	static struct attribute *gpio_keys_attrs[] = {
306	&dev_attr_keys.attr,
307	&dev_attr_switches.attr,
308	&dev_attr_disabled_keys.attr,
309	&dev_attr_disabled_switches.attr,
310	NULL,
311	};
312
313	static struct attribute_group gpio_keys_attr_group = {
314	.attrs = gpio_keys_attrs,
315	};
316
6ee88d71	317	static void gpio_keys_report_event(struct gpio_button_data *bdata)
a33466e3	318	{
ce25d7e9 UKK	319	struct gpio_keys_button *button = bdata->button;
ce25d7e9 UKK	320	struct input_dev *input = bdata->input;
a33466e3 DES	321	unsigned int type = button->type ?: EV_KEY;
	322	int state = (gpio_get_value(button->gpio) ? 1 : 0) ^ button->active_low;
	323
	324	input_event(input, type, button->code, !!state);
	325	input_sync(input);
	326	}
	327
6ee88d71 DM	328	static void gpio_keys_work_func(struct work_struct *work)
	329	{
	330	struct gpio_button_data *bdata =
	331	container_of(work, struct gpio_button_data, work);
	332
	333	gpio_keys_report_event(bdata);
	334	}
	335
da0d03fe	336	static void gpio_keys_timer(unsigned long _data)
ca865a77 JN	337	{
	338	struct gpio_button_data data = (struct gpio_button_data )_data;
	339
da0d03fe	340	schedule_work(&data->work);
ca865a77 JN	341	}
ca865a77 JN	342
78a56aab PB	343	static irqreturn_t gpio_keys_isr(int irq, void *dev_id)
78a56aab PB	344	{
57ffe9d5 UKK	345	struct gpio_button_data *bdata = dev_id;
57ffe9d5 UKK	346	struct gpio_keys_button *button = bdata->button;
78a56aab	347
57ffe9d5	348	BUG_ON(irq != gpio_to_irq(button->gpio));
84767d00	349
ca865a77 JN	350	if (button->debounce_interval)
	351	mod_timer(&bdata->timer,
	352	jiffies + msecs_to_jiffies(button->debounce_interval));
	353	else
da0d03fe	354	schedule_work(&bdata->work);
78a56aab	355
57ffe9d5	356	return IRQ_HANDLED;
78a56aab PB	357	}
78a56aab PB	358
9e3af04f	359	static int __devinit gpio_keys_setup_key(struct platform_device *pdev,
bc8f1eaf BD	360	struct gpio_button_data *bdata,
	361	struct gpio_keys_button *button)
	362	{
	363	char *desc = button->desc ? button->desc : "gpio_keys";
9e3af04f MW	364	struct device *dev = &pdev->dev;
9e3af04f MW	365	unsigned long irqflags;
bc8f1eaf BD	366	int irq, error;
	367
	368	setup_timer(&bdata->timer, gpio_keys_timer, (unsigned long)bdata);
6ee88d71	369	INIT_WORK(&bdata->work, gpio_keys_work_func);
bc8f1eaf BD	370
	371	error = gpio_request(button->gpio, desc);
	372	if (error < 0) {
	373	dev_err(dev, "failed to request GPIO %d, error %d\n",
	374	button->gpio, error);
	375	goto fail2;
	376	}
	377
	378	error = gpio_direction_input(button->gpio);
	379	if (error < 0) {
	380	dev_err(dev, "failed to configure"
	381	" direction for GPIO %d, error %d\n",
	382	button->gpio, error);
	383	goto fail3;
	384	}
	385
	386	irq = gpio_to_irq(button->gpio);
	387	if (irq < 0) {
	388	error = irq;
	389	dev_err(dev, "Unable to get irq number for GPIO %d, error %d\n",
	390	button->gpio, error);
	391	goto fail3;
	392	}
	393
9e3af04f MW	394	irqflags = IRQF_TRIGGER_RISING \| IRQF_TRIGGER_FALLING;
	395	/*
	396	* If platform has specified that the button can be disabled,
	397	* we don't want it to share the interrupt line.
	398	*/
	399	if (!button->can_disable)
	400	irqflags \|= IRQF_SHARED;
	401
	402	error = request_irq(irq, gpio_keys_isr, irqflags, desc, bdata);
bc8f1eaf BD	403	if (error) {
	404	dev_err(dev, "Unable to claim irq %d; error %d\n",
	405	irq, error);
	406	goto fail3;
	407	}
	408
	409	return 0;
	410
	411	fail3:
	412	gpio_free(button->gpio);
	413	fail2:
	414	return error;
	415	}
	416
78a56aab PB	417	static int __devinit gpio_keys_probe(struct platform_device *pdev)
	418	{
	419	struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
a33466e3	420	struct gpio_keys_drvdata *ddata;
db19fd8b	421	struct device *dev = &pdev->dev;
78a56aab PB	422	struct input_dev *input;
78a56aab PB	423	int i, error;
e15b0213	424	int wakeup = 0;
78a56aab	425
a33466e3 DES	426	ddata = kzalloc(sizeof(struct gpio_keys_drvdata) +
	427	pdata->nbuttons * sizeof(struct gpio_button_data),
	428	GFP_KERNEL);
78a56aab	429	input = input_allocate_device();
a33466e3	430	if (!ddata \|\| !input) {
db19fd8b	431	dev_err(dev, "failed to allocate state\n");
a33466e3 DES	432	error = -ENOMEM;
	433	goto fail1;
	434	}
78a56aab	435
9e3af04f MW	436	ddata->input = input;
	437	ddata->n_buttons = pdata->nbuttons;
	438	mutex_init(&ddata->disable_lock);
	439
a33466e3	440	platform_set_drvdata(pdev, ddata);
78a56aab PB	441
	442	input->name = pdev->name;
	443	input->phys = "gpio-keys/input0";
469ba4df	444	input->dev.parent = &pdev->dev;
78a56aab PB	445
	446	input->id.bustype = BUS_HOST;
	447	input->id.vendor = 0x0001;
	448	input->id.product = 0x0001;
	449	input->id.version = 0x0100;
	450
b67b4b11 DC	451	/* Enable auto repeat feature of Linux input subsystem */
	452	if (pdata->rep)
	453	__set_bit(EV_REP, input->evbit);
	454
78a56aab	455	for (i = 0; i < pdata->nbuttons; i++) {
84767d00	456	struct gpio_keys_button *button = &pdata->buttons[i];
a33466e3	457	struct gpio_button_data *bdata = &ddata->data[i];
84767d00	458	unsigned int type = button->type ?: EV_KEY;
78a56aab	459
a33466e3	460	bdata->input = input;
74dd4393	461	bdata->button = button;
bc8f1eaf	462
9e3af04f	463	error = gpio_keys_setup_key(pdev, bdata, button);
bc8f1eaf	464	if (error)
a33466e3	465	goto fail2;
84767d00	466
e15b0213 AS	467	if (button->wakeup)
	468	wakeup = 1;
	469
84767d00	470	input_set_capability(input, type, button->code);
78a56aab PB	471	}
78a56aab PB	472
9e3af04f	473	error = sysfs_create_group(&pdev->dev.kobj, &gpio_keys_attr_group);
78a56aab	474	if (error) {
9e3af04f MW	475	dev_err(dev, "Unable to export keys/switches, error: %d\n",
9e3af04f MW	476	error);
a33466e3	477	goto fail2;
78a56aab PB	478	}
78a56aab PB	479
9e3af04f MW	480	error = input_register_device(input);
	481	if (error) {
	482	dev_err(dev, "Unable to register input device, error: %d\n",
	483	error);
	484	goto fail3;
	485	}
	486
6ee88d71 DM	487	/* get current state of buttons */
	488	for (i = 0; i < pdata->nbuttons; i++)
	489	gpio_keys_report_event(&ddata->data[i]);
	490	input_sync(input);
	491
e15b0213 AS	492	device_init_wakeup(&pdev->dev, wakeup);
e15b0213 AS	493
78a56aab PB	494	return 0;
78a56aab PB	495
9e3af04f MW	496	fail3:
9e3af04f MW	497	sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
a33466e3	498	fail2:
6a2e3911	499	while (--i >= 0) {
57ffe9d5	500	free_irq(gpio_to_irq(pdata->buttons[i].gpio), &ddata->data[i]);
ca865a77 JN	501	if (pdata->buttons[i].debounce_interval)
ca865a77 JN	502	del_timer_sync(&ddata->data[i].timer);
da0d03fe	503	cancel_work_sync(&ddata->data[i].work);
6a2e3911 HVR	504	gpio_free(pdata->buttons[i].gpio);
6a2e3911 HVR	505	}
78a56aab	506
006df302	507	platform_set_drvdata(pdev, NULL);
a33466e3	508	fail1:
78a56aab	509	input_free_device(input);
a33466e3	510	kfree(ddata);
78a56aab PB	511
	512	return error;
	513	}
	514
	515	static int __devexit gpio_keys_remove(struct platform_device *pdev)
	516	{
	517	struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
a33466e3 DES	518	struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
a33466e3 DES	519	struct input_dev *input = ddata->input;
78a56aab PB	520	int i;
78a56aab PB	521
9e3af04f MW	522	sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
9e3af04f MW	523
e15b0213 AS	524	device_init_wakeup(&pdev->dev, 0);
e15b0213 AS	525
78a56aab	526	for (i = 0; i < pdata->nbuttons; i++) {
0d98f6bb	527	int irq = gpio_to_irq(pdata->buttons[i].gpio);
57ffe9d5	528	free_irq(irq, &ddata->data[i]);
ca865a77 JN	529	if (pdata->buttons[i].debounce_interval)
ca865a77 JN	530	del_timer_sync(&ddata->data[i].timer);
da0d03fe	531	cancel_work_sync(&ddata->data[i].work);
6a2e3911	532	gpio_free(pdata->buttons[i].gpio);
78a56aab PB	533	}
	534
	535	input_unregister_device(input);
	536
	537	return 0;
	538	}
	539
e15b0213 AS	540
e15b0213 AS	541	#ifdef CONFIG_PM
ae78e0e0	542	static int gpio_keys_suspend(struct device *dev)
e15b0213	543	{
ae78e0e0	544	struct platform_device *pdev = to_platform_device(dev);
e15b0213 AS	545	struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
	546	int i;
	547
	548	if (device_may_wakeup(&pdev->dev)) {
	549	for (i = 0; i < pdata->nbuttons; i++) {
	550	struct gpio_keys_button *button = &pdata->buttons[i];
	551	if (button->wakeup) {
	552	int irq = gpio_to_irq(button->gpio);
	553	enable_irq_wake(irq);
	554	}
	555	}
	556	}
	557
	558	return 0;
	559	}
	560
ae78e0e0	561	static int gpio_keys_resume(struct device *dev)
e15b0213	562	{
ae78e0e0	563	struct platform_device *pdev = to_platform_device(dev);
6ee88d71	564	struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
e15b0213 AS	565	struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
	566	int i;
	567
6ee88d71 DM	568	for (i = 0; i < pdata->nbuttons; i++) {
	569
	570	struct gpio_keys_button *button = &pdata->buttons[i];
	571	if (button->wakeup && device_may_wakeup(&pdev->dev)) {
	572	int irq = gpio_to_irq(button->gpio);
	573	disable_irq_wake(irq);
e15b0213	574	}
6ee88d71 DM	575
6ee88d71 DM	576	gpio_keys_report_event(&ddata->data[i]);
e15b0213	577	}
6ee88d71	578	input_sync(ddata->input);
e15b0213 AS	579
	580	return 0;
	581	}
ae78e0e0 MR	582
	583	static const struct dev_pm_ops gpio_keys_pm_ops = {
	584	.suspend = gpio_keys_suspend,
	585	.resume = gpio_keys_resume,
	586	};
e15b0213 AS	587	#endif
e15b0213 AS	588
9b07044c	589	static struct platform_driver gpio_keys_device_driver = {
78a56aab PB	590	.probe = gpio_keys_probe,
	591	.remove = __devexit_p(gpio_keys_remove),
	592	.driver = {
	593	.name = "gpio-keys",
d7b5247b	594	.owner = THIS_MODULE,
ae78e0e0 MR	595	#ifdef CONFIG_PM
	596	.pm = &gpio_keys_pm_ops,
	597	#endif
78a56aab PB	598	}
	599	};
	600
	601	static int __init gpio_keys_init(void)
	602	{
	603	return platform_driver_register(&gpio_keys_device_driver);
	604	}
	605
	606	static void __exit gpio_keys_exit(void)
	607	{
	608	platform_driver_unregister(&gpio_keys_device_driver);
	609	}
	610
	611	module_init(gpio_keys_init);
	612	module_exit(gpio_keys_exit);
	613
	614	MODULE_LICENSE("GPL");
	615	MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>");
	616	MODULE_DESCRIPTION("Keyboard driver for CPU GPIOs");
d7b5247b	617	MODULE_ALIAS("platform:gpio-keys");