drivers/input/keyboard/omap4-keypad.c - third_party/linux - Git at Google

 /*
  * OMAP4 Keypad Driver
  *
  * Copyright (C) 2010 Texas Instruments
  *
  * Author: Abraham Arce <x0066660@ti.com>
  * Initial Code: Syed Rafiuddin <rafiuddin.syed@ti.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */

 #include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/errno.h>
 #include <linux/io.h>
 #include <linux/of.h>
 #include <linux/input.h>
 #include <linux/input/matrix_keypad.h>
 #include <linux/slab.h>
 #include <linux/pm_runtime.h>

 /* OMAP4 registers */
 #define OMAP4_KBD_REVISION		0x00
 #define OMAP4_KBD_SYSCONFIG		0x10
 #define OMAP4_KBD_SYSSTATUS		0x14
 #define OMAP4_KBD_IRQSTATUS		0x18
 #define OMAP4_KBD_IRQENABLE		0x1C
 #define OMAP4_KBD_WAKEUPENABLE		0x20
 #define OMAP4_KBD_PENDING		0x24
 #define OMAP4_KBD_CTRL			0x28
 #define OMAP4_KBD_DEBOUNCINGTIME	0x2C
 #define OMAP4_KBD_LONGKEYTIME		0x30
 #define OMAP4_KBD_TIMEOUT		0x34
 #define OMAP4_KBD_STATEMACHINE		0x38
 #define OMAP4_KBD_ROWINPUTS		0x3C
 #define OMAP4_KBD_COLUMNOUTPUTS		0x40
 #define OMAP4_KBD_FULLCODE31_0		0x44
 #define OMAP4_KBD_FULLCODE63_32		0x48

 /* OMAP4 bit definitions */
 #define OMAP4_DEF_IRQENABLE_EVENTEN	BIT(0)
 #define OMAP4_DEF_IRQENABLE_LONGKEY	BIT(1)
 #define OMAP4_DEF_WUP_EVENT_ENA		BIT(0)
 #define OMAP4_DEF_WUP_LONG_KEY_ENA	BIT(1)
 #define OMAP4_DEF_CTRL_NOSOFTMODE	BIT(1)
 #define OMAP4_DEF_CTRL_PTV_SHIFT	2

 /* OMAP4 values */
 #define OMAP4_VAL_IRQDISABLE		0x0

 /*
  * Errata i689: If a key is released for a time shorter than debounce time,
  * the keyboard will idle and never detect the key release. The workaround
  * is to use at least a 12ms debounce time. See omap5432 TRM chapter
  * "26.4.6.2 Keyboard Controller Timer" for more information.
  */
 #define OMAP4_KEYPAD_PTV_DIV_128        0x6
 #define OMAP4_KEYPAD_DEBOUNCINGTIME_MS(dbms, ptv)     \
 	((((dbms) * 1000) / ((1 << ((ptv) + 1)) * (1000000 / 32768))) - 1)
 #define OMAP4_VAL_DEBOUNCINGTIME_16MS					\
 	OMAP4_KEYPAD_DEBOUNCINGTIME_MS(16, OMAP4_KEYPAD_PTV_DIV_128)

 enum {
 	KBD_REVISION_OMAP4 = 0,
 	KBD_REVISION_OMAP5,
 };

 struct omap4_keypad {
 	struct input_dev *input;

 	void __iomem *base;
 	bool irq_wake_enabled;
 	unsigned int irq;

 	unsigned int rows;
 	unsigned int cols;
 	u32 reg_offset;
 	u32 irqreg_offset;
 	unsigned int row_shift;
 	bool no_autorepeat;
 	unsigned char key_state[8];
 	unsigned short *keymap;
 };

 static int kbd_readl(struct omap4_keypad *keypad_data, u32 offset)
 {
 	return __raw_readl(keypad_data->base +
 				keypad_data->reg_offset + offset);
 }

 static void kbd_writel(struct omap4_keypad *keypad_data, u32 offset, u32 value)
 {
 	__raw_writel(value,
 		     keypad_data->base + keypad_data->reg_offset + offset);
 }

 static int kbd_read_irqreg(struct omap4_keypad *keypad_data, u32 offset)
 {
 	return __raw_readl(keypad_data->base +
 				keypad_data->irqreg_offset + offset);
 }

 static void kbd_write_irqreg(struct omap4_keypad *keypad_data,
 			     u32 offset, u32 value)
 {
 	__raw_writel(value,
 		     keypad_data->base + keypad_data->irqreg_offset + offset);
 }


 /* Interrupt handlers */
 static irqreturn_t omap4_keypad_irq_handler(int irq, void *dev_id)
 {
 	struct omap4_keypad *keypad_data = dev_id;

 	if (kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS))
 		return IRQ_WAKE_THREAD;

 	return IRQ_NONE;
 }

 static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id)
 {
 	struct omap4_keypad *keypad_data = dev_id;
 	struct input_dev *input_dev = keypad_data->input;
 	unsigned char key_state[ARRAY_SIZE(keypad_data->key_state)];
 	unsigned int col, row, code, changed;
 	u32 *new_state = (u32 *) key_state;

 	*new_state = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
 	*(new_state + 1) = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);

 	for (row = 0; row < keypad_data->rows; row++) {
 		changed = key_state[row] ^ keypad_data->key_state[row];
 		if (!changed)
 			continue;

 		for (col = 0; col < keypad_data->cols; col++) {
 			if (changed & (1 << col)) {
 				code = MATRIX_SCAN_CODE(row, col,
 						keypad_data->row_shift);
 				input_event(input_dev, EV_MSC, MSC_SCAN, code);
 				input_report_key(input_dev,
 						 keypad_data->keymap[code],
 						 key_state[row] & (1 << col));
 			}
 		}
 	}

 	input_sync(input_dev);

 	memcpy(keypad_data->key_state, key_state,
 		sizeof(keypad_data->key_state));

 	/* clear pending interrupts */
 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));

 	return IRQ_HANDLED;
 }

 static int omap4_keypad_open(struct input_dev *input)
 {
 	struct omap4_keypad *keypad_data = input_get_drvdata(input);

 	pm_runtime_get_sync(input->dev.parent);

 	disable_irq(keypad_data->irq);

 	kbd_writel(keypad_data, OMAP4_KBD_CTRL,
 			OMAP4_DEF_CTRL_NOSOFTMODE |
 			(OMAP4_KEYPAD_PTV_DIV_128 << OMAP4_DEF_CTRL_PTV_SHIFT));
 	kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
 			OMAP4_VAL_DEBOUNCINGTIME_16MS);
 	/* clear pending interrupts */
 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
 			OMAP4_DEF_IRQENABLE_EVENTEN |
 				OMAP4_DEF_IRQENABLE_LONGKEY);
 	kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
 			OMAP4_DEF_WUP_EVENT_ENA | OMAP4_DEF_WUP_LONG_KEY_ENA);

 	enable_irq(keypad_data->irq);

 	return 0;
 }

 static void omap4_keypad_stop(struct omap4_keypad *keypad_data)
 {
 	/* Disable interrupts and wake-up events */
 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
 			 OMAP4_VAL_IRQDISABLE);
 	kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE, 0);

 	/* clear pending interrupts */
 	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
 			 kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
 }

 static void omap4_keypad_close(struct input_dev *input)
 {
 	struct omap4_keypad *keypad_data;

 	keypad_data = input_get_drvdata(input);
 	disable_irq(keypad_data->irq);
 	omap4_keypad_stop(keypad_data);
 	enable_irq(keypad_data->irq);

 	pm_runtime_put_sync(input->dev.parent);
 }

 static int omap4_keypad_parse_dt(struct device *dev,
 				 struct omap4_keypad *keypad_data)
 {
 	struct device_node *np = dev->of_node;
 	int err;

 	err = matrix_keypad_parse_properties(dev, &keypad_data->rows,
 					     &keypad_data->cols);
 	if (err)
 		return err;

 	if (of_get_property(np, "linux,input-no-autorepeat", NULL))
 		keypad_data->no_autorepeat = true;

 	return 0;
 }

 static int omap4_keypad_check_revision(struct device *dev,
 				       struct omap4_keypad *keypad_data)
 {
 	unsigned int rev;

 	rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
 	rev &= 0x03 << 30;
 	rev >>= 30;
 	switch (rev) {
 	case KBD_REVISION_OMAP4:
 		keypad_data->reg_offset = 0x00;
 		keypad_data->irqreg_offset = 0x00;
 		break;
 	case KBD_REVISION_OMAP5:
 		keypad_data->reg_offset = 0x10;
 		keypad_data->irqreg_offset = 0x0c;
 		break;
 	default:
 		dev_err(dev, "Keypad reports unsupported revision %d", rev);
 		return -EINVAL;
 	}

 	return 0;
 }

 static int omap4_keypad_probe(struct platform_device *pdev)
 {
 	struct omap4_keypad *keypad_data;
 	struct input_dev *input_dev;
 	struct resource *res;
 	unsigned int max_keys;
 	int irq;
 	int error;

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res) {
 		dev_err(&pdev->dev, "no base address specified\n");
 		return -EINVAL;
 	}

 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0)
 		return irq;

 	keypad_data = kzalloc(sizeof(struct omap4_keypad), GFP_KERNEL);
 	if (!keypad_data) {
 		dev_err(&pdev->dev, "keypad_data memory allocation failed\n");
 		return -ENOMEM;
 	}

 	keypad_data->irq = irq;

 	error = omap4_keypad_parse_dt(&pdev->dev, keypad_data);
 	if (error)
 		goto err_free_keypad;

 	res = request_mem_region(res->start, resource_size(res), pdev->name);
 	if (!res) {
 		dev_err(&pdev->dev, "can't request mem region\n");
 		error = -EBUSY;
 		goto err_free_keypad;
 	}

 	keypad_data->base = ioremap(res->start, resource_size(res));
 	if (!keypad_data->base) {
 		dev_err(&pdev->dev, "can't ioremap mem resource\n");
 		error = -ENOMEM;
 		goto err_release_mem;
 	}

 	pm_runtime_enable(&pdev->dev);

 	/*
 	 * Enable clocks for the keypad module so that we can read
 	 * revision register.
 	 */
 	error = pm_runtime_get_sync(&pdev->dev);
 	if (error) {
 		dev_err(&pdev->dev, "pm_runtime_get_sync() failed\n");
 		pm_runtime_put_noidle(&pdev->dev);
 	} else {
 		error = omap4_keypad_check_revision(&pdev->dev,
 						    keypad_data);
 		if (!error) {
 			/* Ensure device does not raise interrupts */
 			omap4_keypad_stop(keypad_data);
 		}
 		pm_runtime_put_sync(&pdev->dev);
 	}
 	if (error)
 		goto err_pm_disable;

 	/* input device allocation */
 	keypad_data->input = input_dev = input_allocate_device();
 	if (!input_dev) {
 		error = -ENOMEM;
 		goto err_pm_disable;
 	}

 	input_dev->name = pdev->name;
 	input_dev->dev.parent = &pdev->dev;
 	input_dev->id.bustype = BUS_HOST;
 	input_dev->id.vendor = 0x0001;
 	input_dev->id.product = 0x0001;
 	input_dev->id.version = 0x0001;

 	input_dev->open = omap4_keypad_open;
 	input_dev->close = omap4_keypad_close;

 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
 	if (!keypad_data->no_autorepeat)
 		__set_bit(EV_REP, input_dev->evbit);

 	input_set_drvdata(input_dev, keypad_data);

 	keypad_data->row_shift = get_count_order(keypad_data->cols);
 	max_keys = keypad_data->rows << keypad_data->row_shift;
 	keypad_data->keymap = kcalloc(max_keys,
 				      sizeof(keypad_data->keymap[0]),
 				      GFP_KERNEL);
 	if (!keypad_data->keymap) {
 		dev_err(&pdev->dev, "Not enough memory for keymap\n");
 		error = -ENOMEM;
 		goto err_free_input;
 	}

 	error = matrix_keypad_build_keymap(NULL, NULL,
 					   keypad_data->rows, keypad_data->cols,
 					   keypad_data->keymap, input_dev);
 	if (error) {
 		dev_err(&pdev->dev, "failed to build keymap\n");
 		goto err_free_keymap;
 	}

 	error = request_threaded_irq(keypad_data->irq, omap4_keypad_irq_handler,
 				     omap4_keypad_irq_thread_fn, IRQF_ONESHOT,
 				     "omap4-keypad", keypad_data);
 	if (error) {
 		dev_err(&pdev->dev, "failed to register interrupt\n");
 		goto err_free_keymap;
 	}

 	error = input_register_device(keypad_data->input);
 	if (error < 0) {
 		dev_err(&pdev->dev, "failed to register input device\n");
 		goto err_free_irq;
 	}

 	device_init_wakeup(&pdev->dev, true);
 	platform_set_drvdata(pdev, keypad_data);

 	return 0;

 err_free_irq:
 	free_irq(keypad_data->irq, keypad_data);
 err_free_keymap:
 	kfree(keypad_data->keymap);
 err_free_input:
 	input_free_device(input_dev);
 err_pm_disable:
 	pm_runtime_disable(&pdev->dev);
 	iounmap(keypad_data->base);
 err_release_mem:
 	release_mem_region(res->start, resource_size(res));
 err_free_keypad:
 	kfree(keypad_data);
 	return error;
 }

 static int omap4_keypad_remove(struct platform_device *pdev)
 {
 	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
 	struct resource *res;

 	free_irq(keypad_data->irq, keypad_data);

 	pm_runtime_disable(&pdev->dev);

 	input_unregister_device(keypad_data->input);

 	iounmap(keypad_data->base);

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	release_mem_region(res->start, resource_size(res));

 	kfree(keypad_data->keymap);
 	kfree(keypad_data);

 	return 0;
 }

 static const struct of_device_id omap_keypad_dt_match[] = {
 	{ .compatible = "ti,omap4-keypad" },
 	{},
 };
 MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);

 #ifdef CONFIG_PM_SLEEP
 static int omap4_keypad_suspend(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
 	int error;

 	if (device_may_wakeup(&pdev->dev)) {
 		error = enable_irq_wake(keypad_data->irq);
 		if (!error)
 			keypad_data->irq_wake_enabled = true;
 	}

 	return 0;
 }

 static int omap4_keypad_resume(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);

 	if (device_may_wakeup(&pdev->dev) && keypad_data->irq_wake_enabled) {
 		disable_irq_wake(keypad_data->irq);
 		keypad_data->irq_wake_enabled = false;
 	}

 	return 0;
 }
 #endif

 static SIMPLE_DEV_PM_OPS(omap4_keypad_pm_ops,
 			 omap4_keypad_suspend, omap4_keypad_resume);

 static struct platform_driver omap4_keypad_driver = {
 	.probe		= omap4_keypad_probe,
 	.remove		= omap4_keypad_remove,
 	.driver		= {
 		.name	= "omap4-keypad",
 		.pm	= &omap4_keypad_pm_ops,
 		.of_match_table = omap_keypad_dt_match,
 	},
 };
 module_platform_driver(omap4_keypad_driver);

 MODULE_AUTHOR("Texas Instruments");
 MODULE_DESCRIPTION("OMAP4 Keypad Driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:omap4-keypad");
	/*
	* OMAP4 Keypad Driver
	*
	* Copyright (C) 2010 Texas Instruments
	*
	* Author: Abraham Arce <x0066660@ti.com>
	* Initial Code: Syed Rafiuddin <rafiuddin.syed@ti.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*/

	#include <linux/module.h>
	#include <linux/interrupt.h>
	#include <linux/platform_device.h>
	#include <linux/errno.h>
	#include <linux/io.h>
	#include <linux/of.h>
	#include <linux/input.h>
	#include <linux/input/matrix_keypad.h>
	#include <linux/slab.h>
	#include <linux/pm_runtime.h>

	/* OMAP4 registers */
	#define OMAP4_KBD_REVISION 0x00
	#define OMAP4_KBD_SYSCONFIG 0x10
	#define OMAP4_KBD_SYSSTATUS 0x14
	#define OMAP4_KBD_IRQSTATUS 0x18
	#define OMAP4_KBD_IRQENABLE 0x1C
	#define OMAP4_KBD_WAKEUPENABLE 0x20
	#define OMAP4_KBD_PENDING 0x24
	#define OMAP4_KBD_CTRL 0x28
	#define OMAP4_KBD_DEBOUNCINGTIME 0x2C
	#define OMAP4_KBD_LONGKEYTIME 0x30
	#define OMAP4_KBD_TIMEOUT 0x34
	#define OMAP4_KBD_STATEMACHINE 0x38
	#define OMAP4_KBD_ROWINPUTS 0x3C
	#define OMAP4_KBD_COLUMNOUTPUTS 0x40
	#define OMAP4_KBD_FULLCODE31_0 0x44
	#define OMAP4_KBD_FULLCODE63_32 0x48

	/* OMAP4 bit definitions */
	#define OMAP4_DEF_IRQENABLE_EVENTEN BIT(0)
	#define OMAP4_DEF_IRQENABLE_LONGKEY BIT(1)
	#define OMAP4_DEF_WUP_EVENT_ENA BIT(0)
	#define OMAP4_DEF_WUP_LONG_KEY_ENA BIT(1)
	#define OMAP4_DEF_CTRL_NOSOFTMODE BIT(1)
	#define OMAP4_DEF_CTRL_PTV_SHIFT 2

	/* OMAP4 values */
	#define OMAP4_VAL_IRQDISABLE 0x0

	/*
	* Errata i689: If a key is released for a time shorter than debounce time,
	* the keyboard will idle and never detect the key release. The workaround
	* is to use at least a 12ms debounce time. See omap5432 TRM chapter
	* "26.4.6.2 Keyboard Controller Timer" for more information.
	*/
	#define OMAP4_KEYPAD_PTV_DIV_128 0x6
	#define OMAP4_KEYPAD_DEBOUNCINGTIME_MS(dbms, ptv) \
	((((dbms) * 1000) / ((1 << ((ptv) + 1)) * (1000000 / 32768))) - 1)
	#define OMAP4_VAL_DEBOUNCINGTIME_16MS \
	OMAP4_KEYPAD_DEBOUNCINGTIME_MS(16, OMAP4_KEYPAD_PTV_DIV_128)

	enum {
	KBD_REVISION_OMAP4 = 0,
	KBD_REVISION_OMAP5,
	};

	struct omap4_keypad {
	struct input_dev *input;

	void __iomem *base;
	bool irq_wake_enabled;
	unsigned int irq;

	unsigned int rows;
	unsigned int cols;
	u32 reg_offset;
	u32 irqreg_offset;
	unsigned int row_shift;
	bool no_autorepeat;
	unsigned char key_state[8];
	unsigned short *keymap;
	};

	static int kbd_readl(struct omap4_keypad *keypad_data, u32 offset)
	{
	return __raw_readl(keypad_data->base +
	keypad_data->reg_offset + offset);
	}

	static void kbd_writel(struct omap4_keypad *keypad_data, u32 offset, u32 value)
	{
	__raw_writel(value,
	keypad_data->base + keypad_data->reg_offset + offset);
	}

	static int kbd_read_irqreg(struct omap4_keypad *keypad_data, u32 offset)
	{
	return __raw_readl(keypad_data->base +
	keypad_data->irqreg_offset + offset);
	}

	static void kbd_write_irqreg(struct omap4_keypad *keypad_data,
	u32 offset, u32 value)
	{
	__raw_writel(value,
	keypad_data->base + keypad_data->irqreg_offset + offset);
	}


	/* Interrupt handlers */
	static irqreturn_t omap4_keypad_irq_handler(int irq, void *dev_id)
	{
	struct omap4_keypad *keypad_data = dev_id;

	if (kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS))
	return IRQ_WAKE_THREAD;

	return IRQ_NONE;
	}

	static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id)
	{
	struct omap4_keypad *keypad_data = dev_id;
	struct input_dev *input_dev = keypad_data->input;
	unsigned char key_state[ARRAY_SIZE(keypad_data->key_state)];
	unsigned int col, row, code, changed;
	u32 new_state = (u32 ) key_state;

	*new_state = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
	*(new_state + 1) = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);

	for (row = 0; row < keypad_data->rows; row++) {
	changed = key_state[row] ^ keypad_data->key_state[row];
	if (!changed)
	continue;

	for (col = 0; col < keypad_data->cols; col++) {
	if (changed & (1 << col)) {
	code = MATRIX_SCAN_CODE(row, col,
	keypad_data->row_shift);
	input_event(input_dev, EV_MSC, MSC_SCAN, code);
	input_report_key(input_dev,
	keypad_data->keymap[code],
	key_state[row] & (1 << col));
	}
	}
	}

	input_sync(input_dev);

	memcpy(keypad_data->key_state, key_state,
	sizeof(keypad_data->key_state));

	/* clear pending interrupts */
	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
	kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));

	return IRQ_HANDLED;
	}

	static int omap4_keypad_open(struct input_dev *input)
	{
	struct omap4_keypad *keypad_data = input_get_drvdata(input);

	pm_runtime_get_sync(input->dev.parent);

	disable_irq(keypad_data->irq);

	kbd_writel(keypad_data, OMAP4_KBD_CTRL,
	OMAP4_DEF_CTRL_NOSOFTMODE \|
	(OMAP4_KEYPAD_PTV_DIV_128 << OMAP4_DEF_CTRL_PTV_SHIFT));
	kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
	OMAP4_VAL_DEBOUNCINGTIME_16MS);
	/* clear pending interrupts */
	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
	kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
	OMAP4_DEF_IRQENABLE_EVENTEN \|
	OMAP4_DEF_IRQENABLE_LONGKEY);
	kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
	OMAP4_DEF_WUP_EVENT_ENA \| OMAP4_DEF_WUP_LONG_KEY_ENA);

	enable_irq(keypad_data->irq);

	return 0;
	}

	static void omap4_keypad_stop(struct omap4_keypad *keypad_data)
	{
	/* Disable interrupts and wake-up events */
	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
	OMAP4_VAL_IRQDISABLE);
	kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE, 0);

	/* clear pending interrupts */
	kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
	kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
	}

	static void omap4_keypad_close(struct input_dev *input)
	{
	struct omap4_keypad *keypad_data;

	keypad_data = input_get_drvdata(input);
	disable_irq(keypad_data->irq);
	omap4_keypad_stop(keypad_data);
	enable_irq(keypad_data->irq);

	pm_runtime_put_sync(input->dev.parent);
	}

	static int omap4_keypad_parse_dt(struct device *dev,
	struct omap4_keypad *keypad_data)
	{
	struct device_node *np = dev->of_node;
	int err;

	err = matrix_keypad_parse_properties(dev, &keypad_data->rows,
	&keypad_data->cols);
	if (err)
	return err;

	if (of_get_property(np, "linux,input-no-autorepeat", NULL))
	keypad_data->no_autorepeat = true;

	return 0;
	}

	static int omap4_keypad_check_revision(struct device *dev,
	struct omap4_keypad *keypad_data)
	{
	unsigned int rev;

	rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
	rev &= 0x03 << 30;
	rev >>= 30;
	switch (rev) {
	case KBD_REVISION_OMAP4:
	keypad_data->reg_offset = 0x00;
	keypad_data->irqreg_offset = 0x00;
	break;
	case KBD_REVISION_OMAP5:
	keypad_data->reg_offset = 0x10;
	keypad_data->irqreg_offset = 0x0c;
	break;
	default:
	dev_err(dev, "Keypad reports unsupported revision %d", rev);
	return -EINVAL;
	}

	return 0;
	}

	static int omap4_keypad_probe(struct platform_device *pdev)
	{
	struct omap4_keypad *keypad_data;
	struct input_dev *input_dev;
	struct resource *res;
	unsigned int max_keys;
	int irq;
	int error;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
	dev_err(&pdev->dev, "no base address specified\n");
	return -EINVAL;
	}

	irq = platform_get_irq(pdev, 0);
	if (irq < 0)
	return irq;

	keypad_data = kzalloc(sizeof(struct omap4_keypad), GFP_KERNEL);
	if (!keypad_data) {
	dev_err(&pdev->dev, "keypad_data memory allocation failed\n");
	return -ENOMEM;
	}

	keypad_data->irq = irq;

	error = omap4_keypad_parse_dt(&pdev->dev, keypad_data);
	if (error)
	goto err_free_keypad;

	res = request_mem_region(res->start, resource_size(res), pdev->name);
	if (!res) {
	dev_err(&pdev->dev, "can't request mem region\n");
	error = -EBUSY;
	goto err_free_keypad;
	}

	keypad_data->base = ioremap(res->start, resource_size(res));
	if (!keypad_data->base) {
	dev_err(&pdev->dev, "can't ioremap mem resource\n");
	error = -ENOMEM;
	goto err_release_mem;
	}

	pm_runtime_enable(&pdev->dev);

	/*
	* Enable clocks for the keypad module so that we can read
	* revision register.
	*/
	error = pm_runtime_get_sync(&pdev->dev);
	if (error) {
	dev_err(&pdev->dev, "pm_runtime_get_sync() failed\n");
	pm_runtime_put_noidle(&pdev->dev);
	} else {
	error = omap4_keypad_check_revision(&pdev->dev,
	keypad_data);
	if (!error) {
	/* Ensure device does not raise interrupts */
	omap4_keypad_stop(keypad_data);
	}
	pm_runtime_put_sync(&pdev->dev);
	}
	if (error)
	goto err_pm_disable;

	/* input device allocation */
	keypad_data->input = input_dev = input_allocate_device();
	if (!input_dev) {
	error = -ENOMEM;
	goto err_pm_disable;
	}

	input_dev->name = pdev->name;
	input_dev->dev.parent = &pdev->dev;
	input_dev->id.bustype = BUS_HOST;
	input_dev->id.vendor = 0x0001;
	input_dev->id.product = 0x0001;
	input_dev->id.version = 0x0001;

	input_dev->open = omap4_keypad_open;
	input_dev->close = omap4_keypad_close;

	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
	if (!keypad_data->no_autorepeat)
	__set_bit(EV_REP, input_dev->evbit);

	input_set_drvdata(input_dev, keypad_data);

	keypad_data->row_shift = get_count_order(keypad_data->cols);
	max_keys = keypad_data->rows << keypad_data->row_shift;
	keypad_data->keymap = kcalloc(max_keys,
	sizeof(keypad_data->keymap[0]),
	GFP_KERNEL);
	if (!keypad_data->keymap) {
	dev_err(&pdev->dev, "Not enough memory for keymap\n");
	error = -ENOMEM;
	goto err_free_input;
	}

	error = matrix_keypad_build_keymap(NULL, NULL,
	keypad_data->rows, keypad_data->cols,
	keypad_data->keymap, input_dev);
	if (error) {
	dev_err(&pdev->dev, "failed to build keymap\n");
	goto err_free_keymap;
	}

	error = request_threaded_irq(keypad_data->irq, omap4_keypad_irq_handler,
	omap4_keypad_irq_thread_fn, IRQF_ONESHOT,
	"omap4-keypad", keypad_data);
	if (error) {
	dev_err(&pdev->dev, "failed to register interrupt\n");
	goto err_free_keymap;
	}

	error = input_register_device(keypad_data->input);
	if (error < 0) {
	dev_err(&pdev->dev, "failed to register input device\n");
	goto err_free_irq;
	}

	device_init_wakeup(&pdev->dev, true);
	platform_set_drvdata(pdev, keypad_data);

	return 0;

	err_free_irq:
	free_irq(keypad_data->irq, keypad_data);
	err_free_keymap:
	kfree(keypad_data->keymap);
	err_free_input:
	input_free_device(input_dev);
	err_pm_disable:
	pm_runtime_disable(&pdev->dev);
	iounmap(keypad_data->base);
	err_release_mem:
	release_mem_region(res->start, resource_size(res));
	err_free_keypad:
	kfree(keypad_data);
	return error;
	}

	static int omap4_keypad_remove(struct platform_device *pdev)
	{
	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
	struct resource *res;

	free_irq(keypad_data->irq, keypad_data);

	pm_runtime_disable(&pdev->dev);

	input_unregister_device(keypad_data->input);

	iounmap(keypad_data->base);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	release_mem_region(res->start, resource_size(res));

	kfree(keypad_data->keymap);
	kfree(keypad_data);

	return 0;
	}

	static const struct of_device_id omap_keypad_dt_match[] = {
	{ .compatible = "ti,omap4-keypad" },
	{},
	};
	MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);

	#ifdef CONFIG_PM_SLEEP
	static int omap4_keypad_suspend(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
	int error;

	if (device_may_wakeup(&pdev->dev)) {
	error = enable_irq_wake(keypad_data->irq);
	if (!error)
	keypad_data->irq_wake_enabled = true;
	}

	return 0;
	}

	static int omap4_keypad_resume(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);

	if (device_may_wakeup(&pdev->dev) && keypad_data->irq_wake_enabled) {
	disable_irq_wake(keypad_data->irq);
	keypad_data->irq_wake_enabled = false;
	}

	return 0;
	}
	#endif

	static SIMPLE_DEV_PM_OPS(omap4_keypad_pm_ops,
	omap4_keypad_suspend, omap4_keypad_resume);

	static struct platform_driver omap4_keypad_driver = {
	.probe = omap4_keypad_probe,
	.remove = omap4_keypad_remove,
	.driver = {
	.name = "omap4-keypad",
	.pm = &omap4_keypad_pm_ops,
	.of_match_table = omap_keypad_dt_match,
	},
	};
	module_platform_driver(omap4_keypad_driver);

	MODULE_AUTHOR("Texas Instruments");
	MODULE_DESCRIPTION("OMAP4 Keypad Driver");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:omap4-keypad");