drivers/input/keyboard/gpio_keys_polled.c - maze/linux - Git at Google

 /*
  *  Driver for buttons on GPIO lines not capable of generating interrupts
  *
  *  Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org>
  *  Copyright (C) 2010 Nuno Goncalves <nunojpg@gmail.com>
  *
  *  This file was based on: /drivers/input/misc/cobalt_btns.c
  *	Copyright (C) 2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
  *
  *  also was based on: /drivers/input/keyboard/gpio_keys.c
  *	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/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/input.h>
 #include <linux/input-polldev.h>
 #include <linux/ioport.h>
 #include <linux/platform_device.h>
 #include <linux/gpio.h>
 #include <linux/gpio_keys.h>
 #include <linux/of_platform.h>
 #include <linux/of_gpio.h>

 #define DRV_NAME	"gpio-keys-polled"

 struct gpio_keys_button_data {
 	int last_state;
 	int count;
 	int threshold;
 	int can_sleep;
 };

 struct gpio_keys_polled_dev {
 	struct input_polled_dev *poll_dev;
 	struct device *dev;
 	const struct gpio_keys_platform_data *pdata;
 	struct gpio_keys_button_data data[0];
 };

 static void gpio_keys_polled_check_state(struct input_dev *input,
 					 struct gpio_keys_button *button,
 					 struct gpio_keys_button_data *bdata)
 {
 	int state;

 	if (bdata->can_sleep)
 		state = !!gpio_get_value_cansleep(button->gpio);
 	else
 		state = !!gpio_get_value(button->gpio);

 	if (state != bdata->last_state) {
 		unsigned int type = button->type ?: EV_KEY;

 		input_event(input, type, button->code,
 			    !!(state ^ button->active_low));
 		input_sync(input);
 		bdata->count = 0;
 		bdata->last_state = state;
 	}
 }

 static void gpio_keys_polled_poll(struct input_polled_dev *dev)
 {
 	struct gpio_keys_polled_dev *bdev = dev->private;
 	const struct gpio_keys_platform_data *pdata = bdev->pdata;
 	struct input_dev *input = dev->input;
 	int i;

 	for (i = 0; i < pdata->nbuttons; i++) {
 		struct gpio_keys_button_data *bdata = &bdev->data[i];

 		if (bdata->count < bdata->threshold)
 			bdata->count++;
 		else
 			gpio_keys_polled_check_state(input, &pdata->buttons[i],
 						     bdata);
 	}
 }

 static void gpio_keys_polled_open(struct input_polled_dev *dev)
 {
 	struct gpio_keys_polled_dev *bdev = dev->private;
 	const struct gpio_keys_platform_data *pdata = bdev->pdata;

 	if (pdata->enable)
 		pdata->enable(bdev->dev);
 }

 static void gpio_keys_polled_close(struct input_polled_dev *dev)
 {
 	struct gpio_keys_polled_dev *bdev = dev->private;
 	const struct gpio_keys_platform_data *pdata = bdev->pdata;

 	if (pdata->disable)
 		pdata->disable(bdev->dev);
 }

 #ifdef CONFIG_OF
 static struct gpio_keys_platform_data *gpio_keys_polled_get_devtree_pdata(struct device *dev)
 {
 	struct device_node *node, *pp;
 	struct gpio_keys_platform_data *pdata;
 	struct gpio_keys_button *button;
 	int error;
 	int nbuttons;
 	int i;

 	node = dev->of_node;
 	if (!node)
 		return NULL;

 	nbuttons = of_get_child_count(node);
 	if (nbuttons == 0)
 		return NULL;

 	pdata = kzalloc(sizeof(*pdata) + nbuttons * (sizeof *button),
 			GFP_KERNEL);
 	if (!pdata) {
 		error = -ENOMEM;
 		goto err_out;
 	}

 	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);

 	i = 0;
 	for_each_child_of_node(node, pp) {
 		int gpio;
 		enum of_gpio_flags flags;

 		if (!of_find_property(pp, "gpios", NULL)) {
 			pdata->nbuttons--;
 			dev_warn(dev, "Found button without gpios\n");
 			continue;
 		}

 		gpio = of_get_gpio_flags(pp, 0, &flags);
 		if (gpio < 0) {
 			error = gpio;
 			if (error != -EPROBE_DEFER)
 				dev_err(dev,
 					"Failed to get gpio flags, error: %d\n",
 					error);
 			goto err_free_pdata;
 		}

 		button = &pdata->buttons[i++];

 		button->gpio = gpio;
 		button->active_low = flags & OF_GPIO_ACTIVE_LOW;

 		if (of_property_read_u32(pp, "linux,code", &button->code)) {
 			dev_err(dev, "Button without keycode: 0x%x\n",
 				button->gpio);
 			error = -EINVAL;
 			goto err_free_pdata;
 		}

 		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;
 	}

 	if (pdata->nbuttons == 0) {
 		error = -EINVAL;
 		goto err_free_pdata;
 	}

 	return pdata;

 err_free_pdata:
 	kfree(pdata);
 err_out:
 	return ERR_PTR(error);
 }

 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_polled_get_devtree_pdata(struct device *dev)
 {
 	return NULL;
 }
 #endif

 static int gpio_keys_polled_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev);
 	struct gpio_keys_polled_dev *bdev;
 	struct input_polled_dev *poll_dev;
 	struct input_dev *input;
 	int error;
 	int i;

 	if (!pdata) {
 		pdata = gpio_keys_polled_get_devtree_pdata(dev);
 		if (IS_ERR(pdata))
 			return PTR_ERR(pdata);
 		if (!pdata) {
 			dev_err(dev, "missing platform data\n");
 			return -EINVAL;
 		}
 	}

 	if (!pdata->poll_interval) {
 		dev_err(dev, "missing poll_interval value\n");
 		error = -EINVAL;
 		goto err_free_pdata;
 	}

 	bdev = kzalloc(sizeof(struct gpio_keys_polled_dev) +
 		       pdata->nbuttons * sizeof(struct gpio_keys_button_data),
 		       GFP_KERNEL);
 	if (!bdev) {
 		dev_err(dev, "no memory for private data\n");
 		error = -ENOMEM;
 		goto err_free_pdata;
 	}

 	poll_dev = input_allocate_polled_device();
 	if (!poll_dev) {
 		dev_err(dev, "no memory for polled device\n");
 		error = -ENOMEM;
 		goto err_free_bdev;
 	}

 	poll_dev->private = bdev;
 	poll_dev->poll = gpio_keys_polled_poll;
 	poll_dev->poll_interval = pdata->poll_interval;
 	poll_dev->open = gpio_keys_polled_open;
 	poll_dev->close = gpio_keys_polled_close;

 	input = poll_dev->input;

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

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

 	__set_bit(EV_KEY, input->evbit);
 	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_keys_button_data *bdata = &bdev->data[i];
 		unsigned int gpio = button->gpio;
 		unsigned int type = button->type ?: EV_KEY;

 		if (button->wakeup) {
 			dev_err(dev, DRV_NAME " does not support wakeup\n");
 			error = -EINVAL;
 			goto err_free_gpio;
 		}

 		error = gpio_request_one(gpio, GPIOF_IN,
 					 button->desc ?: DRV_NAME);
 		if (error) {
 			dev_err(dev, "unable to claim gpio %u, err=%d\n",
 				gpio, error);
 			goto err_free_gpio;
 		}

 		bdata->can_sleep = gpio_cansleep(gpio);
 		bdata->last_state = -1;
 		bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
 						pdata->poll_interval);

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

 	bdev->poll_dev = poll_dev;
 	bdev->dev = dev;
 	bdev->pdata = pdata;
 	platform_set_drvdata(pdev, bdev);

 	error = input_register_polled_device(poll_dev);
 	if (error) {
 		dev_err(dev, "unable to register polled device, err=%d\n",
 			error);
 		goto err_free_gpio;
 	}

 	/* report initial state of the buttons */
 	for (i = 0; i < pdata->nbuttons; i++)
 		gpio_keys_polled_check_state(input, &pdata->buttons[i],
 					     &bdev->data[i]);

 	return 0;

 err_free_gpio:
 	while (--i >= 0)
 		gpio_free(pdata->buttons[i].gpio);

 	input_free_polled_device(poll_dev);

 err_free_bdev:
 	kfree(bdev);

 err_free_pdata:
 	/* If we have no platform_data, we allocated pdata dynamically.  */
 	if (!dev_get_platdata(&pdev->dev))
 		kfree(pdata);

 	return error;
 }

 static int gpio_keys_polled_remove(struct platform_device *pdev)
 {
 	struct gpio_keys_polled_dev *bdev = platform_get_drvdata(pdev);
 	const struct gpio_keys_platform_data *pdata = bdev->pdata;
 	int i;

 	input_unregister_polled_device(bdev->poll_dev);

 	for (i = 0; i < pdata->nbuttons; i++)
 		gpio_free(pdata->buttons[i].gpio);

 	input_free_polled_device(bdev->poll_dev);

 	/*
 	 * If we had no platform_data, we allocated pdata dynamically and
 	 * must free it here.
 	 */
 	if (!dev_get_platdata(&pdev->dev))
 		kfree(pdata);

 	kfree(bdev);

 	return 0;
 }

 static struct platform_driver gpio_keys_polled_driver = {
 	.probe	= gpio_keys_polled_probe,
 	.remove	= gpio_keys_polled_remove,
 	.driver	= {
 		.name	= DRV_NAME,
 		.owner	= THIS_MODULE,
 		.of_match_table = of_match_ptr(gpio_keys_polled_of_match),
 	},
 };
 module_platform_driver(gpio_keys_polled_driver);

 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 MODULE_DESCRIPTION("Polled GPIO Buttons driver");
 MODULE_ALIAS("platform:" DRV_NAME);
	/*
	* Driver for buttons on GPIO lines not capable of generating interrupts
	*
	* Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org>
	* Copyright (C) 2010 Nuno Goncalves <nunojpg@gmail.com>
	*
	* This file was based on: /drivers/input/misc/cobalt_btns.c
	* Copyright (C) 2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
	*
	* also was based on: /drivers/input/keyboard/gpio_keys.c
	* 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/kernel.h>
	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/slab.h>
	#include <linux/input.h>
	#include <linux/input-polldev.h>
	#include <linux/ioport.h>
	#include <linux/platform_device.h>
	#include <linux/gpio.h>
	#include <linux/gpio_keys.h>
	#include <linux/of_platform.h>
	#include <linux/of_gpio.h>

	#define DRV_NAME "gpio-keys-polled"

	struct gpio_keys_button_data {
	int last_state;
	int count;
	int threshold;
	int can_sleep;
	};

	struct gpio_keys_polled_dev {
	struct input_polled_dev *poll_dev;
	struct device *dev;
	const struct gpio_keys_platform_data *pdata;
	struct gpio_keys_button_data data[0];
	};

	static void gpio_keys_polled_check_state(struct input_dev *input,
	struct gpio_keys_button *button,
	struct gpio_keys_button_data *bdata)
	{
	int state;

	if (bdata->can_sleep)
	state = !!gpio_get_value_cansleep(button->gpio);
	else
	state = !!gpio_get_value(button->gpio);

	if (state != bdata->last_state) {
	unsigned int type = button->type ?: EV_KEY;

	input_event(input, type, button->code,
	!!(state ^ button->active_low));
	input_sync(input);
	bdata->count = 0;
	bdata->last_state = state;
	}
	}

	static void gpio_keys_polled_poll(struct input_polled_dev *dev)
	{
	struct gpio_keys_polled_dev *bdev = dev->private;
	const struct gpio_keys_platform_data *pdata = bdev->pdata;
	struct input_dev *input = dev->input;
	int i;

	for (i = 0; i < pdata->nbuttons; i++) {
	struct gpio_keys_button_data *bdata = &bdev->data[i];

	if (bdata->count < bdata->threshold)
	bdata->count++;
	else
	gpio_keys_polled_check_state(input, &pdata->buttons[i],
	bdata);
	}
	}

	static void gpio_keys_polled_open(struct input_polled_dev *dev)
	{
	struct gpio_keys_polled_dev *bdev = dev->private;
	const struct gpio_keys_platform_data *pdata = bdev->pdata;

	if (pdata->enable)
	pdata->enable(bdev->dev);
	}

	static void gpio_keys_polled_close(struct input_polled_dev *dev)
	{
	struct gpio_keys_polled_dev *bdev = dev->private;
	const struct gpio_keys_platform_data *pdata = bdev->pdata;

	if (pdata->disable)
	pdata->disable(bdev->dev);
	}

	#ifdef CONFIG_OF
	static struct gpio_keys_platform_data gpio_keys_polled_get_devtree_pdata(struct device dev)
	{
	struct device_node node, pp;
	struct gpio_keys_platform_data *pdata;
	struct gpio_keys_button *button;
	int error;
	int nbuttons;
	int i;

	node = dev->of_node;
	if (!node)
	return NULL;

	nbuttons = of_get_child_count(node);
	if (nbuttons == 0)
	return NULL;

	pdata = kzalloc(sizeof(pdata) + nbuttons (sizeof *button),
	GFP_KERNEL);
	if (!pdata) {
	error = -ENOMEM;
	goto err_out;
	}

	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);

	i = 0;
	for_each_child_of_node(node, pp) {
	int gpio;
	enum of_gpio_flags flags;

	if (!of_find_property(pp, "gpios", NULL)) {
	pdata->nbuttons--;
	dev_warn(dev, "Found button without gpios\n");
	continue;
	}

	gpio = of_get_gpio_flags(pp, 0, &flags);
	if (gpio < 0) {
	error = gpio;
	if (error != -EPROBE_DEFER)
	dev_err(dev,
	"Failed to get gpio flags, error: %d\n",
	error);
	goto err_free_pdata;
	}

	button = &pdata->buttons[i++];

	button->gpio = gpio;
	button->active_low = flags & OF_GPIO_ACTIVE_LOW;

	if (of_property_read_u32(pp, "linux,code", &button->code)) {
	dev_err(dev, "Button without keycode: 0x%x\n",
	button->gpio);
	error = -EINVAL;
	goto err_free_pdata;
	}

	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;
	}

	if (pdata->nbuttons == 0) {
	error = -EINVAL;
	goto err_free_pdata;
	}

	return pdata;

	err_free_pdata:
	kfree(pdata);
	err_out:
	return ERR_PTR(error);
	}

	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_polled_get_devtree_pdata(struct device *dev)
	{
	return NULL;
	}
	#endif

	static int gpio_keys_polled_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev);
	struct gpio_keys_polled_dev *bdev;
	struct input_polled_dev *poll_dev;
	struct input_dev *input;
	int error;
	int i;

	if (!pdata) {
	pdata = gpio_keys_polled_get_devtree_pdata(dev);
	if (IS_ERR(pdata))
	return PTR_ERR(pdata);
	if (!pdata) {
	dev_err(dev, "missing platform data\n");
	return -EINVAL;
	}
	}

	if (!pdata->poll_interval) {
	dev_err(dev, "missing poll_interval value\n");
	error = -EINVAL;
	goto err_free_pdata;
	}

	bdev = kzalloc(sizeof(struct gpio_keys_polled_dev) +
	pdata->nbuttons * sizeof(struct gpio_keys_button_data),
	GFP_KERNEL);
	if (!bdev) {
	dev_err(dev, "no memory for private data\n");
	error = -ENOMEM;
	goto err_free_pdata;
	}

	poll_dev = input_allocate_polled_device();
	if (!poll_dev) {
	dev_err(dev, "no memory for polled device\n");
	error = -ENOMEM;
	goto err_free_bdev;
	}

	poll_dev->private = bdev;
	poll_dev->poll = gpio_keys_polled_poll;
	poll_dev->poll_interval = pdata->poll_interval;
	poll_dev->open = gpio_keys_polled_open;
	poll_dev->close = gpio_keys_polled_close;

	input = poll_dev->input;

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

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

	__set_bit(EV_KEY, input->evbit);
	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_keys_button_data *bdata = &bdev->data[i];
	unsigned int gpio = button->gpio;
	unsigned int type = button->type ?: EV_KEY;

	if (button->wakeup) {
	dev_err(dev, DRV_NAME " does not support wakeup\n");
	error = -EINVAL;
	goto err_free_gpio;
	}

	error = gpio_request_one(gpio, GPIOF_IN,
	button->desc ?: DRV_NAME);
	if (error) {
	dev_err(dev, "unable to claim gpio %u, err=%d\n",
	gpio, error);
	goto err_free_gpio;
	}

	bdata->can_sleep = gpio_cansleep(gpio);
	bdata->last_state = -1;
	bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
	pdata->poll_interval);

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

	bdev->poll_dev = poll_dev;
	bdev->dev = dev;
	bdev->pdata = pdata;
	platform_set_drvdata(pdev, bdev);

	error = input_register_polled_device(poll_dev);
	if (error) {
	dev_err(dev, "unable to register polled device, err=%d\n",
	error);
	goto err_free_gpio;
	}

	/* report initial state of the buttons */
	for (i = 0; i < pdata->nbuttons; i++)
	gpio_keys_polled_check_state(input, &pdata->buttons[i],
	&bdev->data[i]);

	return 0;

	err_free_gpio:
	while (--i >= 0)
	gpio_free(pdata->buttons[i].gpio);

	input_free_polled_device(poll_dev);

	err_free_bdev:
	kfree(bdev);

	err_free_pdata:
	/* If we have no platform_data, we allocated pdata dynamically. */
	if (!dev_get_platdata(&pdev->dev))
	kfree(pdata);

	return error;
	}

	static int gpio_keys_polled_remove(struct platform_device *pdev)
	{
	struct gpio_keys_polled_dev *bdev = platform_get_drvdata(pdev);
	const struct gpio_keys_platform_data *pdata = bdev->pdata;
	int i;

	input_unregister_polled_device(bdev->poll_dev);

	for (i = 0; i < pdata->nbuttons; i++)
	gpio_free(pdata->buttons[i].gpio);

	input_free_polled_device(bdev->poll_dev);

	/*
	* If we had no platform_data, we allocated pdata dynamically and
	* must free it here.
	*/
	if (!dev_get_platdata(&pdev->dev))
	kfree(pdata);

	kfree(bdev);

	return 0;
	}

	static struct platform_driver gpio_keys_polled_driver = {
	.probe = gpio_keys_polled_probe,
	.remove = gpio_keys_polled_remove,
	.driver = {
	.name = DRV_NAME,
	.owner = THIS_MODULE,
	.of_match_table = of_match_ptr(gpio_keys_polled_of_match),
	},
	};
	module_platform_driver(gpio_keys_polled_driver);

	MODULE_LICENSE("GPL v2");
	MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
	MODULE_DESCRIPTION("Polled GPIO Buttons driver");
	MODULE_ALIAS("platform:" DRV_NAME);