drivers/input/keyboard/spear-keyboard.c - kernel/msm-4.9 - Gitiles

 /*
  * SPEAr Keyboard Driver
  * Based on omap-keypad driver
  *
  * Copyright (C) 2010 ST Microelectronics
  * Rajeev Kumar<rajeev-dlh.kumar@st.com>
  *
  * This file is licensed under the terms of the GNU General Public
  * License version 2. This program is licensed "as is" without any
  * warranty of any kind, whether express or implied.
  */

 #include <linux/clk.h>
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/input.h>
 #include <linux/io.h>
 #include <linux/irq.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm_wakeup.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 #include <linux/platform_data/keyboard-spear.h>

 /* Keyboard Registers */
 #define MODE_CTL_REG	0x00
 #define STATUS_REG	0x0C
 #define DATA_REG	0x10
 #define INTR_MASK	0x54

 /* Register Values */
 #define NUM_ROWS	16
 #define NUM_COLS	16
 #define MODE_CTL_PCLK_FREQ_SHIFT	9
 #define MODE_CTL_PCLK_FREQ_MSK		0x7F

 #define MODE_CTL_KEYBOARD	(0x2 << 0)
 #define MODE_CTL_SCAN_RATE_10	(0x0 << 2)
 #define MODE_CTL_SCAN_RATE_20	(0x1 << 2)
 #define MODE_CTL_SCAN_RATE_40	(0x2 << 2)
 #define MODE_CTL_SCAN_RATE_80	(0x3 << 2)
 #define MODE_CTL_KEYNUM_SHIFT	6
 #define MODE_CTL_START_SCAN	(0x1 << 8)

 #define STATUS_DATA_AVAIL	(0x1 << 1)

 #define DATA_ROW_MASK		0xF0
 #define DATA_COLUMN_MASK	0x0F

 #define ROW_SHIFT		4

 struct spear_kbd {
 	struct input_dev *input;
 	void __iomem *io_base;
 	struct clk *clk;
 	unsigned int irq;
 	unsigned int mode;
 	unsigned int suspended_rate;
 	unsigned short last_key;
 	unsigned short keycodes[NUM_ROWS * NUM_COLS];
 	bool rep;
 	bool irq_wake_enabled;
 	u32 mode_ctl_reg;
 };

 static irqreturn_t spear_kbd_interrupt(int irq, void *dev_id)
 {
 	struct spear_kbd *kbd = dev_id;
 	struct input_dev *input = kbd->input;
 	unsigned int key;
 	u32 sts, val;

 	sts = readl_relaxed(kbd->io_base + STATUS_REG);
 	if (!(sts & STATUS_DATA_AVAIL))
 		return IRQ_NONE;

 	if (kbd->last_key != KEY_RESERVED) {
 		input_report_key(input, kbd->last_key, 0);
 		kbd->last_key = KEY_RESERVED;
 	}

 	/* following reads active (row, col) pair */
 	val = readl_relaxed(kbd->io_base + DATA_REG) &
 		(DATA_ROW_MASK | DATA_COLUMN_MASK);
 	key = kbd->keycodes[val];

 	input_event(input, EV_MSC, MSC_SCAN, val);
 	input_report_key(input, key, 1);
 	input_sync(input);

 	kbd->last_key = key;

 	/* clear interrupt */
 	writel_relaxed(0, kbd->io_base + STATUS_REG);

 	return IRQ_HANDLED;
 }

 static int spear_kbd_open(struct input_dev *dev)
 {
 	struct spear_kbd *kbd = input_get_drvdata(dev);
 	int error;
 	u32 val;

 	kbd->last_key = KEY_RESERVED;

 	error = clk_enable(kbd->clk);
 	if (error)
 		return error;

 	/* keyboard rate to be programmed is input clock (in MHz) - 1 */
 	val = clk_get_rate(kbd->clk) / 1000000 - 1;
 	val = (val & MODE_CTL_PCLK_FREQ_MSK) << MODE_CTL_PCLK_FREQ_SHIFT;

 	/* program keyboard */
 	val = MODE_CTL_SCAN_RATE_80 | MODE_CTL_KEYBOARD | val |
 		(kbd->mode << MODE_CTL_KEYNUM_SHIFT);
 	writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
 	writel_relaxed(1, kbd->io_base + STATUS_REG);

 	/* start key scan */
 	val = readl_relaxed(kbd->io_base + MODE_CTL_REG);
 	val |= MODE_CTL_START_SCAN;
 	writel_relaxed(val, kbd->io_base + MODE_CTL_REG);

 	return 0;
 }

 static void spear_kbd_close(struct input_dev *dev)
 {
 	struct spear_kbd *kbd = input_get_drvdata(dev);
 	u32 val;

 	/* stop key scan */
 	val = readl_relaxed(kbd->io_base + MODE_CTL_REG);
 	val &= ~MODE_CTL_START_SCAN;
 	writel_relaxed(val, kbd->io_base + MODE_CTL_REG);

 	clk_disable(kbd->clk);

 	kbd->last_key = KEY_RESERVED;
 }

 #ifdef CONFIG_OF
 static int spear_kbd_parse_dt(struct platform_device *pdev,
                                         struct spear_kbd *kbd)
 {
 	struct device_node *np = pdev->dev.of_node;
 	int error;
 	u32 val, suspended_rate;

 	if (!np) {
 		dev_err(&pdev->dev, "Missing DT data\n");
 		return -EINVAL;
 	}

 	if (of_property_read_bool(np, "autorepeat"))
 		kbd->rep = true;

 	if (of_property_read_u32(np, "suspended_rate", &suspended_rate))
 		kbd->suspended_rate = suspended_rate;

 	error = of_property_read_u32(np, "st,mode", &val);
 	if (error) {
 		dev_err(&pdev->dev, "DT: Invalid or missing mode\n");
 		return error;
 	}

 	kbd->mode = val;
 	return 0;
 }
 #else
 static inline int spear_kbd_parse_dt(struct platform_device *pdev,
 				     struct spear_kbd *kbd)
 {
 	return -ENOSYS;
 }
 #endif

 static int spear_kbd_probe(struct platform_device *pdev)
 {
 	struct kbd_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	const struct matrix_keymap_data *keymap = pdata ? pdata->keymap : NULL;
 	struct spear_kbd *kbd;
 	struct input_dev *input_dev;
 	struct resource *res;
 	int irq;
 	int error;

 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0) {
 		dev_err(&pdev->dev, "not able to get irq for the device\n");
 		return irq;
 	}

 	kbd = devm_kzalloc(&pdev->dev, sizeof(*kbd), GFP_KERNEL);
 	if (!kbd) {
 		dev_err(&pdev->dev, "not enough memory for driver data\n");
 		return -ENOMEM;
 	}

 	input_dev = devm_input_allocate_device(&pdev->dev);
 	if (!input_dev) {
 		dev_err(&pdev->dev, "unable to allocate input device\n");
 		return -ENOMEM;
 	}

 	kbd->input = input_dev;
 	kbd->irq = irq;

 	if (!pdata) {
 		error = spear_kbd_parse_dt(pdev, kbd);
 		if (error)
 			return error;
 	} else {
 		kbd->mode = pdata->mode;
 		kbd->rep = pdata->rep;
 		kbd->suspended_rate = pdata->suspended_rate;
 	}

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	kbd->io_base = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(kbd->io_base))
 		return PTR_ERR(kbd->io_base);

 	kbd->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(kbd->clk))
 		return PTR_ERR(kbd->clk);

 	input_dev->name = "Spear Keyboard";
 	input_dev->phys = "keyboard/input0";
 	input_dev->id.bustype = BUS_HOST;
 	input_dev->id.vendor = 0x0001;
 	input_dev->id.product = 0x0001;
 	input_dev->id.version = 0x0100;
 	input_dev->open = spear_kbd_open;
 	input_dev->close = spear_kbd_close;

 	error = matrix_keypad_build_keymap(keymap, NULL, NUM_ROWS, NUM_COLS,
 					   kbd->keycodes, input_dev);
 	if (error) {
 		dev_err(&pdev->dev, "Failed to build keymap\n");
 		return error;
 	}

 	if (kbd->rep)
 		__set_bit(EV_REP, input_dev->evbit);
 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);

 	input_set_drvdata(input_dev, kbd);

 	error = devm_request_irq(&pdev->dev, irq, spear_kbd_interrupt, 0,
 			"keyboard", kbd);
 	if (error) {
 		dev_err(&pdev->dev, "request_irq failed\n");
 		return error;
 	}

 	error = clk_prepare(kbd->clk);
 	if (error)
 		return error;

 	error = input_register_device(input_dev);
 	if (error) {
 		dev_err(&pdev->dev, "Unable to register keyboard device\n");
 		clk_unprepare(kbd->clk);
 		return error;
 	}

 	device_init_wakeup(&pdev->dev, 1);
 	platform_set_drvdata(pdev, kbd);

 	return 0;
 }

 static int spear_kbd_remove(struct platform_device *pdev)
 {
 	struct spear_kbd *kbd = platform_get_drvdata(pdev);

 	input_unregister_device(kbd->input);
 	clk_unprepare(kbd->clk);

 	device_init_wakeup(&pdev->dev, 0);

 	return 0;
 }

 #ifdef CONFIG_PM
 static int spear_kbd_suspend(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct spear_kbd *kbd = platform_get_drvdata(pdev);
 	struct input_dev *input_dev = kbd->input;
 	unsigned int rate = 0, mode_ctl_reg, val;

 	mutex_lock(&input_dev->mutex);

 	/* explicitly enable clock as we may program device */
 	clk_enable(kbd->clk);

 	mode_ctl_reg = readl_relaxed(kbd->io_base + MODE_CTL_REG);

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

 		/*
 		 * reprogram the keyboard operating frequency as on some
 		 * platform it may change during system suspended
 		 */
 		if (kbd->suspended_rate)
 			rate = kbd->suspended_rate / 1000000 - 1;
 		else
 			rate = clk_get_rate(kbd->clk) / 1000000 - 1;

 		val = mode_ctl_reg &
 			~(MODE_CTL_PCLK_FREQ_MSK << MODE_CTL_PCLK_FREQ_SHIFT);
 		val |= (rate & MODE_CTL_PCLK_FREQ_MSK)
 			<< MODE_CTL_PCLK_FREQ_SHIFT;
 		writel_relaxed(val, kbd->io_base + MODE_CTL_REG);

 	} else {
 		if (input_dev->users) {
 			writel_relaxed(mode_ctl_reg & ~MODE_CTL_START_SCAN,
 					kbd->io_base + MODE_CTL_REG);
 			clk_disable(kbd->clk);
 		}
 	}

 	/* store current configuration */
 	if (input_dev->users)
 		kbd->mode_ctl_reg = mode_ctl_reg;

 	/* restore previous clk state */
 	clk_disable(kbd->clk);

 	mutex_unlock(&input_dev->mutex);

 	return 0;
 }

 static int spear_kbd_resume(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct spear_kbd *kbd = platform_get_drvdata(pdev);
 	struct input_dev *input_dev = kbd->input;

 	mutex_lock(&input_dev->mutex);

 	if (device_may_wakeup(&pdev->dev)) {
 		if (kbd->irq_wake_enabled) {
 			kbd->irq_wake_enabled = false;
 			disable_irq_wake(kbd->irq);
 		}
 	} else {
 		if (input_dev->users)
 			clk_enable(kbd->clk);
 	}

 	/* restore current configuration */
 	if (input_dev->users)
 		writel_relaxed(kbd->mode_ctl_reg, kbd->io_base + MODE_CTL_REG);

 	mutex_unlock(&input_dev->mutex);

 	return 0;
 }
 #endif

 static SIMPLE_DEV_PM_OPS(spear_kbd_pm_ops, spear_kbd_suspend, spear_kbd_resume);

 #ifdef CONFIG_OF
 static const struct of_device_id spear_kbd_id_table[] = {
 	{ .compatible = "st,spear300-kbd" },
 	{}
 };
 MODULE_DEVICE_TABLE(of, spear_kbd_id_table);
 #endif

 static struct platform_driver spear_kbd_driver = {
 	.probe		= spear_kbd_probe,
 	.remove		= spear_kbd_remove,
 	.driver		= {
 		.name	= "keyboard",
 		.owner	= THIS_MODULE,
 		.pm	= &spear_kbd_pm_ops,
 		.of_match_table = of_match_ptr(spear_kbd_id_table),
 	},
 };
 module_platform_driver(spear_kbd_driver);

 MODULE_AUTHOR("Rajeev Kumar");
 MODULE_DESCRIPTION("SPEAr Keyboard Driver");
 MODULE_LICENSE("GPL");
	/*
	* SPEAr Keyboard Driver
	* Based on omap-keypad driver
	*
	* Copyright (C) 2010 ST Microelectronics
	* Rajeev Kumar<rajeev-dlh.kumar@st.com>
	*
	* This file is licensed under the terms of the GNU General Public
	* License version 2. This program is licensed "as is" without any
	* warranty of any kind, whether express or implied.
	*/

	#include <linux/clk.h>
	#include <linux/errno.h>
	#include <linux/init.h>
	#include <linux/interrupt.h>
	#include <linux/input.h>
	#include <linux/io.h>
	#include <linux/irq.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/platform_device.h>
	#include <linux/pm_wakeup.h>
	#include <linux/slab.h>
	#include <linux/types.h>
	#include <linux/platform_data/keyboard-spear.h>

	/* Keyboard Registers */
	#define MODE_CTL_REG 0x00
	#define STATUS_REG 0x0C
	#define DATA_REG 0x10
	#define INTR_MASK 0x54

	/* Register Values */
	#define NUM_ROWS 16
	#define NUM_COLS 16
	#define MODE_CTL_PCLK_FREQ_SHIFT 9
	#define MODE_CTL_PCLK_FREQ_MSK 0x7F

	#define MODE_CTL_KEYBOARD (0x2 << 0)
	#define MODE_CTL_SCAN_RATE_10 (0x0 << 2)
	#define MODE_CTL_SCAN_RATE_20 (0x1 << 2)
	#define MODE_CTL_SCAN_RATE_40 (0x2 << 2)
	#define MODE_CTL_SCAN_RATE_80 (0x3 << 2)
	#define MODE_CTL_KEYNUM_SHIFT 6
	#define MODE_CTL_START_SCAN (0x1 << 8)

	#define STATUS_DATA_AVAIL (0x1 << 1)

	#define DATA_ROW_MASK 0xF0
	#define DATA_COLUMN_MASK 0x0F

	#define ROW_SHIFT 4

	struct spear_kbd {
	struct input_dev *input;
	void __iomem *io_base;
	struct clk *clk;
	unsigned int irq;
	unsigned int mode;
	unsigned int suspended_rate;
	unsigned short last_key;
	unsigned short keycodes[NUM_ROWS * NUM_COLS];
	bool rep;
	bool irq_wake_enabled;
	u32 mode_ctl_reg;
	};

	static irqreturn_t spear_kbd_interrupt(int irq, void *dev_id)
	{
	struct spear_kbd *kbd = dev_id;
	struct input_dev *input = kbd->input;
	unsigned int key;
	u32 sts, val;

	sts = readl_relaxed(kbd->io_base + STATUS_REG);
	if (!(sts & STATUS_DATA_AVAIL))
	return IRQ_NONE;

	if (kbd->last_key != KEY_RESERVED) {
	input_report_key(input, kbd->last_key, 0);
	kbd->last_key = KEY_RESERVED;
	}

	/* following reads active (row, col) pair */
	val = readl_relaxed(kbd->io_base + DATA_REG) &
	(DATA_ROW_MASK \| DATA_COLUMN_MASK);
	key = kbd->keycodes[val];

	input_event(input, EV_MSC, MSC_SCAN, val);
	input_report_key(input, key, 1);
	input_sync(input);

	kbd->last_key = key;

	/* clear interrupt */
	writel_relaxed(0, kbd->io_base + STATUS_REG);

	return IRQ_HANDLED;
	}

	static int spear_kbd_open(struct input_dev *dev)
	{
	struct spear_kbd *kbd = input_get_drvdata(dev);
	int error;
	u32 val;

	kbd->last_key = KEY_RESERVED;

	error = clk_enable(kbd->clk);
	if (error)
	return error;

	/* keyboard rate to be programmed is input clock (in MHz) - 1 */
	val = clk_get_rate(kbd->clk) / 1000000 - 1;
	val = (val & MODE_CTL_PCLK_FREQ_MSK) << MODE_CTL_PCLK_FREQ_SHIFT;

	/* program keyboard */
	val = MODE_CTL_SCAN_RATE_80 \| MODE_CTL_KEYBOARD \| val \|
	(kbd->mode << MODE_CTL_KEYNUM_SHIFT);
	writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
	writel_relaxed(1, kbd->io_base + STATUS_REG);

	/* start key scan */
	val = readl_relaxed(kbd->io_base + MODE_CTL_REG);
	val \|= MODE_CTL_START_SCAN;
	writel_relaxed(val, kbd->io_base + MODE_CTL_REG);

	return 0;
	}

	static void spear_kbd_close(struct input_dev *dev)
	{
	struct spear_kbd *kbd = input_get_drvdata(dev);
	u32 val;

	/* stop key scan */
	val = readl_relaxed(kbd->io_base + MODE_CTL_REG);
	val &= ~MODE_CTL_START_SCAN;
	writel_relaxed(val, kbd->io_base + MODE_CTL_REG);

	clk_disable(kbd->clk);

	kbd->last_key = KEY_RESERVED;
	}

	#ifdef CONFIG_OF
	static int spear_kbd_parse_dt(struct platform_device *pdev,
	struct spear_kbd *kbd)
	{
	struct device_node *np = pdev->dev.of_node;
	int error;
	u32 val, suspended_rate;

	if (!np) {
	dev_err(&pdev->dev, "Missing DT data\n");
	return -EINVAL;
	}

	if (of_property_read_bool(np, "autorepeat"))
	kbd->rep = true;

	if (of_property_read_u32(np, "suspended_rate", &suspended_rate))
	kbd->suspended_rate = suspended_rate;

	error = of_property_read_u32(np, "st,mode", &val);
	if (error) {
	dev_err(&pdev->dev, "DT: Invalid or missing mode\n");
	return error;
	}

	kbd->mode = val;
	return 0;
	}
	#else
	static inline int spear_kbd_parse_dt(struct platform_device *pdev,
	struct spear_kbd *kbd)
	{
	return -ENOSYS;
	}
	#endif

	static int spear_kbd_probe(struct platform_device *pdev)
	{
	struct kbd_platform_data *pdata = dev_get_platdata(&pdev->dev);
	const struct matrix_keymap_data *keymap = pdata ? pdata->keymap : NULL;
	struct spear_kbd *kbd;
	struct input_dev *input_dev;
	struct resource *res;
	int irq;
	int error;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
	dev_err(&pdev->dev, "not able to get irq for the device\n");
	return irq;
	}

	kbd = devm_kzalloc(&pdev->dev, sizeof(*kbd), GFP_KERNEL);
	if (!kbd) {
	dev_err(&pdev->dev, "not enough memory for driver data\n");
	return -ENOMEM;
	}

	input_dev = devm_input_allocate_device(&pdev->dev);
	if (!input_dev) {
	dev_err(&pdev->dev, "unable to allocate input device\n");
	return -ENOMEM;
	}

	kbd->input = input_dev;
	kbd->irq = irq;

	if (!pdata) {
	error = spear_kbd_parse_dt(pdev, kbd);
	if (error)
	return error;
	} else {
	kbd->mode = pdata->mode;
	kbd->rep = pdata->rep;
	kbd->suspended_rate = pdata->suspended_rate;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	kbd->io_base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(kbd->io_base))
	return PTR_ERR(kbd->io_base);

	kbd->clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(kbd->clk))
	return PTR_ERR(kbd->clk);

	input_dev->name = "Spear Keyboard";
	input_dev->phys = "keyboard/input0";
	input_dev->id.bustype = BUS_HOST;
	input_dev->id.vendor = 0x0001;
	input_dev->id.product = 0x0001;
	input_dev->id.version = 0x0100;
	input_dev->open = spear_kbd_open;
	input_dev->close = spear_kbd_close;

	error = matrix_keypad_build_keymap(keymap, NULL, NUM_ROWS, NUM_COLS,
	kbd->keycodes, input_dev);
	if (error) {
	dev_err(&pdev->dev, "Failed to build keymap\n");
	return error;
	}

	if (kbd->rep)
	__set_bit(EV_REP, input_dev->evbit);
	input_set_capability(input_dev, EV_MSC, MSC_SCAN);

	input_set_drvdata(input_dev, kbd);

	error = devm_request_irq(&pdev->dev, irq, spear_kbd_interrupt, 0,
	"keyboard", kbd);
	if (error) {
	dev_err(&pdev->dev, "request_irq failed\n");
	return error;
	}

	error = clk_prepare(kbd->clk);
	if (error)
	return error;

	error = input_register_device(input_dev);
	if (error) {
	dev_err(&pdev->dev, "Unable to register keyboard device\n");
	clk_unprepare(kbd->clk);
	return error;
	}

	device_init_wakeup(&pdev->dev, 1);
	platform_set_drvdata(pdev, kbd);

	return 0;
	}

	static int spear_kbd_remove(struct platform_device *pdev)
	{
	struct spear_kbd *kbd = platform_get_drvdata(pdev);

	input_unregister_device(kbd->input);
	clk_unprepare(kbd->clk);

	device_init_wakeup(&pdev->dev, 0);

	return 0;
	}

	#ifdef CONFIG_PM
	static int spear_kbd_suspend(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct spear_kbd *kbd = platform_get_drvdata(pdev);
	struct input_dev *input_dev = kbd->input;
	unsigned int rate = 0, mode_ctl_reg, val;

	mutex_lock(&input_dev->mutex);

	/* explicitly enable clock as we may program device */
	clk_enable(kbd->clk);

	mode_ctl_reg = readl_relaxed(kbd->io_base + MODE_CTL_REG);

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

	/*
	* reprogram the keyboard operating frequency as on some
	* platform it may change during system suspended
	*/
	if (kbd->suspended_rate)
	rate = kbd->suspended_rate / 1000000 - 1;
	else
	rate = clk_get_rate(kbd->clk) / 1000000 - 1;

	val = mode_ctl_reg &
	~(MODE_CTL_PCLK_FREQ_MSK << MODE_CTL_PCLK_FREQ_SHIFT);
	val \|= (rate & MODE_CTL_PCLK_FREQ_MSK)
	<< MODE_CTL_PCLK_FREQ_SHIFT;
	writel_relaxed(val, kbd->io_base + MODE_CTL_REG);

	} else {
	if (input_dev->users) {
	writel_relaxed(mode_ctl_reg & ~MODE_CTL_START_SCAN,
	kbd->io_base + MODE_CTL_REG);
	clk_disable(kbd->clk);
	}
	}

	/* store current configuration */
	if (input_dev->users)
	kbd->mode_ctl_reg = mode_ctl_reg;

	/* restore previous clk state */
	clk_disable(kbd->clk);

	mutex_unlock(&input_dev->mutex);

	return 0;
	}

	static int spear_kbd_resume(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct spear_kbd *kbd = platform_get_drvdata(pdev);
	struct input_dev *input_dev = kbd->input;

	mutex_lock(&input_dev->mutex);

	if (device_may_wakeup(&pdev->dev)) {
	if (kbd->irq_wake_enabled) {
	kbd->irq_wake_enabled = false;
	disable_irq_wake(kbd->irq);
	}
	} else {
	if (input_dev->users)
	clk_enable(kbd->clk);
	}

	/* restore current configuration */
	if (input_dev->users)
	writel_relaxed(kbd->mode_ctl_reg, kbd->io_base + MODE_CTL_REG);

	mutex_unlock(&input_dev->mutex);

	return 0;
	}
	#endif

	static SIMPLE_DEV_PM_OPS(spear_kbd_pm_ops, spear_kbd_suspend, spear_kbd_resume);

	#ifdef CONFIG_OF
	static const struct of_device_id spear_kbd_id_table[] = {
	{ .compatible = "st,spear300-kbd" },
	{}
	};
	MODULE_DEVICE_TABLE(of, spear_kbd_id_table);
	#endif

	static struct platform_driver spear_kbd_driver = {
	.probe = spear_kbd_probe,
	.remove = spear_kbd_remove,
	.driver = {
	.name = "keyboard",
	.owner = THIS_MODULE,
	.pm = &spear_kbd_pm_ops,
	.of_match_table = of_match_ptr(spear_kbd_id_table),
	},
	};
	module_platform_driver(spear_kbd_driver);

	MODULE_AUTHOR("Rajeev Kumar");
	MODULE_DESCRIPTION("SPEAr Keyboard Driver");
	MODULE_LICENSE("GPL");