[PATCHv5] Input: keypad: Add smsc ece1099 keypad driver

Commit Message

Poddar, Sourav Oct. 29, 2012, 10:38 a.m. UTC

From: G, Manjunath Kondaiah <[e-mail]>

SMSC ECE1099 is a keyboard scan or GPIO expansion device.The device
supports a keypad scan matrix of 23*8.This driver uses this
device as a keypad driver.

Tested on omap5430 evm with 3.7-rc1 kernel.

Cc: Benoit Cousson <[e-mail]>
Cc: Felipe Balbi <[e-mail]>
Cc: Santosh Shilimkar <[e-mail]>
Signed-off-by: G, Manjunath Kondaiah <[e-mail]>
Signed-off-by: Sourav Poddar <[e-mail]>
Acked-by: Felipe Balbi <[e-mail]>
---
v4->v5
- changed to use manage resource input framework
- rearrange report event into a seperate api.
- change hex values to lowercase throughout.
- Implement ->open and ->close apis.
- cleanup of unused variable and structure.
 drivers/input/keyboard/Kconfig               |   13 +
 drivers/input/keyboard/Makefile              |    1 +
 drivers/input/keyboard/smsc-ece1099-keypad.c |  310 ++++++++++++++++++++++++++
 3 files changed, 324 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/keyboard/smsc-ece1099-keypad.c

Comments

Felipe Balbi Oct. 29, 2012, 4:20 p.m. UTC | #1

Hi,

On Mon, Oct 29, 2012 at 04:08:49PM +0530, Sourav Poddar wrote:
> +static int __devinit
> +smsc_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct input_dev *input;
> +	struct smsc_keypad *kp;
> +	int ret = 0;
> +	int i, max_keys, row_shift;
> +	int irq;
> +	int addr;
> +
> +	kp = devm_kzalloc(dev, sizeof(*kp), GFP_KERNEL);
> +
> +	input = devm_input_allocate_device(dev);
> +	if (!kp || !input)
> +		ret = -ENOMEM;
> +
> +	ret = smsc_keypad_parse_dt(dev, kp);
> +	if (ret)
> +		return ret;
> +
> +	/* Get the debug Device */
> +	kp->input = input;
> +	kp->irq = platform_get_irq(pdev, 0);
> +	kp->dev = dev;
> +
> +	/* setup input device */
> +	 __set_bit(EV_KEY, input->evbit);
> +
> +	/* Enable auto repeat feature of Linux input subsystem */
> +	if (!kp->no_autorepeat)
> +		__set_bit(EV_REP, input->evbit);
> +
> +	input_set_capability(input, EV_MSC, MSC_SCAN);
> +	input->name             = "SMSC Keypad";
> +	input->phys             = "smsc_keypad/input0";
> +	input->dev.parent       = &pdev->dev;
> +	input->id.bustype       = BUS_HOST;
> +	input->id.vendor        = 0x0001;
> +	input->id.product       = 0x0001;
> +	input->id.version       = 0x0003;
> +
> +	input->open = smsc_keypad_open;
> +	input->close = smsc_keypad_close;
> +	input_set_drvdata(input, kp);
> +
> +	/* Mask all GPIO interrupts (0x37-0x3B) */
> +	for (addr = SMSC_GPIO_INT_MASK_START;
> +			addr < SMSC_GPIO_INT_MASK_START + 4; addr++)
> +		smsc_write(dev, addr, 0);
> +
> +	/* Set all outputs high (0x05-0x09) */
> +	for (addr = SMSC_GPIO_DATA_OUT_START;
> +			addr < SMSC_GPIO_DATA_OUT_START + 4; addr++)
> +		smsc_write(dev, addr, 0xff);
> +
> +	/* Clear all GPIO interrupts (0x32-0x36) */
> +	for (addr = SMSC_GPIO_INT_STAT_START;
> +			addr < SMSC_GPIO_INT_STAT_START + 4; addr++)
> +		smsc_write(dev, addr, 0xff);
> +
> +	/* Configure the smsc pins as Keyboard scan Input */
> +	for (i = 0; i < kp->rows; i++) {
> +		addr = 0x12 + i;
> +		smsc_write(dev, addr, SMSC_KP_KSI);
> +	}
> +
> +	/* Configure the smsc pins as Keyboard scan output */
> +	for (i = 0; i < kp->cols; i++) {
> +		addr = 0x1a + i;
> +		smsc_write(dev, addr, SMSC_KP_KSO);
> +	}
> +
> +	smsc_write(dev, SMSC_KP_INT_STAT, SMSC_KP_SET_HIGH);
> +	smsc_write(dev, SMSC_WKUP_CTRL, SMSC_KP_SET_LOW_PWR);
> +	smsc_write(dev, SMSC_KP_OUT, SMSC_KSO_ALL_LOW);
> +
> +	row_shift = get_count_order(kp->cols);
> +	max_keys = kp->rows << row_shift;
> +
> +	kp->row_shift = row_shift;
> +	kp->keymap = devm_kzalloc(dev, max_keys * sizeof(kp->keymap[0]),
> +					GFP_KERNEL);
> +	if (!kp->keymap) {
> +		dev_err(dev, "Not enough memory for keymap\n");
> +		return -ENOMEM;
> +	}
> +
> +	ret = matrix_keypad_build_keymap(NULL, NULL, kp->rows,
> +			kp->cols, kp->keymap, input);
> +	if (ret) {
> +		dev_err(dev, "failed to build keymap\n");
> +		return ret;
> +	}
> +
> +	/*
> +	* This ISR will always execute in kernel thread context because of
> +	* the need to access the SMSC over the I2C bus.
> +	*/
> +	ret = devm_request_threaded_irq(dev, kp->irq, NULL, do_kp_irq,
> +			IRQF_TRIGGER_FALLING | IRQF_ONESHOT, pdev->name, kp);
> +	if (ret) {
> +		dev_dbg(dev, "request_irq failed for irq no=%d\n",
> +			irq);
> +		return ret;
> +	}
> +
> +	ret = input_register_device(input);
> +	if (ret) {
> +		dev_err(kp->dev,
> +			"Unable to register twl4030 keypad device\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int __devexit smsc_remove(struct platform_device *pdev)
> +{

shouldn't you unregister the input device here ??

Dmitry Torokhov Oct. 29, 2012, 5:06 p.m. UTC | #2

On Mon, Oct 29, 2012 at 06:20:45PM +0200, Felipe Balbi wrote:
> Hi,
> 
> On Mon, Oct 29, 2012 at 04:08:49PM +0530, Sourav Poddar wrote:
> > +static int __devinit
> > +smsc_probe(struct platform_device *pdev)
> > +{
> > +	struct device *dev = &pdev->dev;
> > +	struct input_dev *input;
> > +	struct smsc_keypad *kp;
> > +	int ret = 0;
> > +	int i, max_keys, row_shift;
> > +	int irq;
> > +	int addr;
> > +
> > +	kp = devm_kzalloc(dev, sizeof(*kp), GFP_KERNEL);
> > +
> > +	input = devm_input_allocate_device(dev);
> > +	if (!kp || !input)
> > +		ret = -ENOMEM;
> > +
> > +	ret = smsc_keypad_parse_dt(dev, kp);
> > +	if (ret)
> > +		return ret;
> > +
> > +	/* Get the debug Device */
> > +	kp->input = input;
> > +	kp->irq = platform_get_irq(pdev, 0);
> > +	kp->dev = dev;
> > +
> > +	/* setup input device */
> > +	 __set_bit(EV_KEY, input->evbit);
> > +
> > +	/* Enable auto repeat feature of Linux input subsystem */
> > +	if (!kp->no_autorepeat)
> > +		__set_bit(EV_REP, input->evbit);
> > +
> > +	input_set_capability(input, EV_MSC, MSC_SCAN);
> > +	input->name             = "SMSC Keypad";
> > +	input->phys             = "smsc_keypad/input0";
> > +	input->dev.parent       = &pdev->dev;
> > +	input->id.bustype       = BUS_HOST;
> > +	input->id.vendor        = 0x0001;
> > +	input->id.product       = 0x0001;
> > +	input->id.version       = 0x0003;
> > +
> > +	input->open = smsc_keypad_open;
> > +	input->close = smsc_keypad_close;
> > +	input_set_drvdata(input, kp);
> > +
> > +	/* Mask all GPIO interrupts (0x37-0x3B) */
> > +	for (addr = SMSC_GPIO_INT_MASK_START;
> > +			addr < SMSC_GPIO_INT_MASK_START + 4; addr++)
> > +		smsc_write(dev, addr, 0);
> > +
> > +	/* Set all outputs high (0x05-0x09) */
> > +	for (addr = SMSC_GPIO_DATA_OUT_START;
> > +			addr < SMSC_GPIO_DATA_OUT_START + 4; addr++)
> > +		smsc_write(dev, addr, 0xff);
> > +
> > +	/* Clear all GPIO interrupts (0x32-0x36) */
> > +	for (addr = SMSC_GPIO_INT_STAT_START;
> > +			addr < SMSC_GPIO_INT_STAT_START + 4; addr++)
> > +		smsc_write(dev, addr, 0xff);
> > +
> > +	/* Configure the smsc pins as Keyboard scan Input */
> > +	for (i = 0; i < kp->rows; i++) {
> > +		addr = 0x12 + i;
> > +		smsc_write(dev, addr, SMSC_KP_KSI);
> > +	}
> > +
> > +	/* Configure the smsc pins as Keyboard scan output */
> > +	for (i = 0; i < kp->cols; i++) {
> > +		addr = 0x1a + i;
> > +		smsc_write(dev, addr, SMSC_KP_KSO);
> > +	}
> > +
> > +	smsc_write(dev, SMSC_KP_INT_STAT, SMSC_KP_SET_HIGH);
> > +	smsc_write(dev, SMSC_WKUP_CTRL, SMSC_KP_SET_LOW_PWR);
> > +	smsc_write(dev, SMSC_KP_OUT, SMSC_KSO_ALL_LOW);
> > +
> > +	row_shift = get_count_order(kp->cols);
> > +	max_keys = kp->rows << row_shift;
> > +
> > +	kp->row_shift = row_shift;
> > +	kp->keymap = devm_kzalloc(dev, max_keys * sizeof(kp->keymap[0]),
> > +					GFP_KERNEL);
> > +	if (!kp->keymap) {
> > +		dev_err(dev, "Not enough memory for keymap\n");
> > +		return -ENOMEM;
> > +	}
> > +
> > +	ret = matrix_keypad_build_keymap(NULL, NULL, kp->rows,
> > +			kp->cols, kp->keymap, input);
> > +	if (ret) {
> > +		dev_err(dev, "failed to build keymap\n");
> > +		return ret;
> > +	}
> > +
> > +	/*
> > +	* This ISR will always execute in kernel thread context because of
> > +	* the need to access the SMSC over the I2C bus.
> > +	*/
> > +	ret = devm_request_threaded_irq(dev, kp->irq, NULL, do_kp_irq,
> > +			IRQF_TRIGGER_FALLING | IRQF_ONESHOT, pdev->name, kp);
> > +	if (ret) {
> > +		dev_dbg(dev, "request_irq failed for irq no=%d\n",
> > +			irq);
> > +		return ret;
> > +	}
> > +
> > +	ret = input_register_device(input);
> > +	if (ret) {
> > +		dev_err(kp->dev,
> > +			"Unable to register twl4030 keypad device\n");
> > +		return ret;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int __devexit smsc_remove(struct platform_device *pdev)
> > +{
> 
> shouldn't you unregister the input device here ??

And that is why I do not like devm_* interface myself... But no, since
input device was allocated with devm_input_allocate_device() it does not
need to be explicitly freed or unregistered.

Thanks.

Felipe Balbi Oct. 29, 2012, 7:05 p.m. UTC | #3

Hi,

On Mon, Oct 29, 2012 at 10:06:33AM -0700, Dmitry Torokhov wrote:

[ big snip ]

> > > +static int __devexit smsc_remove(struct platform_device *pdev)
> > > +{
> > 
> > shouldn't you unregister the input device here ??
> 
> And that is why I do not like devm_* interface myself... But no, since
> input device was allocated with devm_input_allocate_device() it does not
> need to be explicitly freed or unregistered.

IMHO, that's a fragility on current devm implementation for input
devices, then.

devm_input_allocate_device() is *only* allocating the input device (at
least judging by the name). Looks like you should introduce
devm_input_register_device() ? What happens if I
devm_input_allocate_device() but don't go as far as
input_register_device() (some error happens in-between) ?

I'm sure you have some proper handling for it, but it's quite misleading
the way this was implemented.

Dmitry Torokhov Oct. 29, 2012, 8:45 p.m. UTC | #4

On Mon, Oct 29, 2012 at 09:05:53PM +0200, Felipe Balbi wrote:
> Hi,
> 
> On Mon, Oct 29, 2012 at 10:06:33AM -0700, Dmitry Torokhov wrote:
> 
> [ big snip ]
> 
> > > > +static int __devexit smsc_remove(struct platform_device *pdev)
> > > > +{
> > > 
> > > shouldn't you unregister the input device here ??
> > 
> > And that is why I do not like devm_* interface myself... But no, since
> > input device was allocated with devm_input_allocate_device() it does not
> > need to be explicitly freed or unregistered.
> 
> IMHO, that's a fragility on current devm implementation for input
> devices, then.
> 
> devm_input_allocate_device() is *only* allocating the input device (at
> least judging by the name). Looks like you should introduce
> devm_input_register_device() ? What happens if I
> devm_input_allocate_device() but don't go as far as
> input_register_device() (some error happens in-between) ?
> 

It will be freed automatically.

> I'm sure you have some proper handling for it, but it's quite misleading
> the way this was implemented.

Well, I could add devm_input_register_device(),
devm_input_unregister_device(), devm_input_free_device() and then add
checks to "normal" input_register_device(), input_unregister_device()
and input_free_device() to throw warnings and errors if they are used
with managed resources, and similarly add checks to devm_* API so that
they are not called with unmanaged devices and make a big mess out of
it.

_OR_ I could just add one new call devm_input_allocate_device() to
create managed input devices and make the rest of old API work with both
managed and unmanaged input devices. I think the latter is much better.

Thanks.

Poddar, Sourav Oct. 30, 2012, 5:31 a.m. UTC | #5

Hi Felipe,
On Monday 29 October 2012 09:50 PM, Felipe Balbi wrote:
> Hi,
>
> On Mon, Oct 29, 2012 at 04:08:49PM +0530, Sourav Poddar wrote:
>> +static int __devinit
>> +smsc_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct input_dev *input;
>> +	struct smsc_keypad *kp;
>> +	int ret = 0;
>> +	int i, max_keys, row_shift;
>> +	int irq;
>> +	int addr;
>> +
>> +	kp = devm_kzalloc(dev, sizeof(*kp), GFP_KERNEL);
>> +
>> +	input = devm_input_allocate_device(dev);
>> +	if (!kp || !input)
>> +		ret = -ENOMEM;
>> +
>> +	ret = smsc_keypad_parse_dt(dev, kp);
>> +	if (ret)
>> +		return ret;
>> +
>> +	/* Get the debug Device */
>> +	kp->input = input;
>> +	kp->irq = platform_get_irq(pdev, 0);
>> +	kp->dev = dev;
>> +
>> +	/* setup input device */
>> +	 __set_bit(EV_KEY, input->evbit);
>> +
>> +	/* Enable auto repeat feature of Linux input subsystem */
>> +	if (!kp->no_autorepeat)
>> +		__set_bit(EV_REP, input->evbit);
>> +
>> +	input_set_capability(input, EV_MSC, MSC_SCAN);
>> +	input->name             = "SMSC Keypad";
>> +	input->phys             = "smsc_keypad/input0";
>> +	input->dev.parent       = &pdev->dev;
>> +	input->id.bustype       = BUS_HOST;
>> +	input->id.vendor        = 0x0001;
>> +	input->id.product       = 0x0001;
>> +	input->id.version       = 0x0003;
>> +
>> +	input->open = smsc_keypad_open;
>> +	input->close = smsc_keypad_close;
>> +	input_set_drvdata(input, kp);
>> +
>> +	/* Mask all GPIO interrupts (0x37-0x3B) */
>> +	for (addr = SMSC_GPIO_INT_MASK_START;
>> +			addr < SMSC_GPIO_INT_MASK_START + 4; addr++)
>> +		smsc_write(dev, addr, 0);
>> +
>> +	/* Set all outputs high (0x05-0x09) */
>> +	for (addr = SMSC_GPIO_DATA_OUT_START;
>> +			addr < SMSC_GPIO_DATA_OUT_START + 4; addr++)
>> +		smsc_write(dev, addr, 0xff);
>> +
>> +	/* Clear all GPIO interrupts (0x32-0x36) */
>> +	for (addr = SMSC_GPIO_INT_STAT_START;
>> +			addr < SMSC_GPIO_INT_STAT_START + 4; addr++)
>> +		smsc_write(dev, addr, 0xff);
>> +
>> +	/* Configure the smsc pins as Keyboard scan Input */
>> +	for (i = 0; i < kp->rows; i++) {
>> +		addr = 0x12 + i;
>> +		smsc_write(dev, addr, SMSC_KP_KSI);
>> +	}
>> +
>> +	/* Configure the smsc pins as Keyboard scan output */
>> +	for (i = 0; i < kp->cols; i++) {
>> +		addr = 0x1a + i;
>> +		smsc_write(dev, addr, SMSC_KP_KSO);
>> +	}
>> +
>> +	smsc_write(dev, SMSC_KP_INT_STAT, SMSC_KP_SET_HIGH);
>> +	smsc_write(dev, SMSC_WKUP_CTRL, SMSC_KP_SET_LOW_PWR);
>> +	smsc_write(dev, SMSC_KP_OUT, SMSC_KSO_ALL_LOW);
>> +
>> +	row_shift = get_count_order(kp->cols);
>> +	max_keys = kp->rows << row_shift;
>> +
>> +	kp->row_shift = row_shift;
>> +	kp->keymap = devm_kzalloc(dev, max_keys * sizeof(kp->keymap[0]),
>> +					GFP_KERNEL);
>> +	if (!kp->keymap) {
>> +		dev_err(dev, "Not enough memory for keymap\n");
>> +		return -ENOMEM;
>> +	}
>> +
>> +	ret = matrix_keypad_build_keymap(NULL, NULL, kp->rows,
>> +			kp->cols, kp->keymap, input);
>> +	if (ret) {
>> +		dev_err(dev, "failed to build keymap\n");
>> +		return ret;
>> +	}
>> +
>> +	/*
>> +	* This ISR will always execute in kernel thread context because of
>> +	* the need to access the SMSC over the I2C bus.
>> +	*/
>> +	ret = devm_request_threaded_irq(dev, kp->irq, NULL, do_kp_irq,
>> +			IRQF_TRIGGER_FALLING | IRQF_ONESHOT, pdev->name, kp);
>> +	if (ret) {
>> +		dev_dbg(dev, "request_irq failed for irq no=%d\n",
>> +			irq);
>> +		return ret;
>> +	}
>> +
>> +	ret = input_register_device(input);
>> +	if (ret) {
>> +		dev_err(kp->dev,
>> +			"Unable to register twl4030 keypad device\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int __devexit smsc_remove(struct platform_device *pdev)
>> +{
> shouldn't you unregister the input device here ??
>
As Dmitry already pointed out, I was also thinking on the same line that 
using devm_* variants
will automatically take care of unregistering your device.
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Patch

diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index b4b65af..af3f3d0 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -593,6 +593,19 @@  config KEYBOARD_TWL4030
 	  To compile this driver as a module, choose M here: the
 	  module will be called twl4030_keypad.
 
+config KEYBOARD_SMSC
+       tristate "SMSC ECE1099 keypad support"
+       depends on I2C && OF
+       depends on MFD_SMSC
+       select INPUT_MATRIXKMAP
+       help
+         Say Y here if your board use the smsc keypad controller
+         for omap5 defconfig. It's safe to say enable this
+         even on boards that don't use the keypad controller.
+
+         To compile this driver as a module, choose M here: the
+         module will be called smsc-ece1099-keypad.
+
 config KEYBOARD_XTKBD
 	tristate "XT keyboard"
 	select SERIO
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 44e7600..0f2aa26 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -52,5 +52,6 @@  obj-$(CONFIG_KEYBOARD_TC3589X)		+= tc3589x-keypad.o
 obj-$(CONFIG_KEYBOARD_TEGRA)		+= tegra-kbc.o
 obj-$(CONFIG_KEYBOARD_TNETV107X)	+= tnetv107x-keypad.o
 obj-$(CONFIG_KEYBOARD_TWL4030)		+= twl4030_keypad.o
+obj-$(CONFIG_KEYBOARD_SMSC)            += smsc-ece1099-keypad.o
 obj-$(CONFIG_KEYBOARD_XTKBD)		+= xtkbd.o
 obj-$(CONFIG_KEYBOARD_W90P910)		+= w90p910_keypad.o
diff --git a/drivers/input/keyboard/smsc-ece1099-keypad.c b/drivers/input/keyboard/smsc-ece1099-keypad.c
new file mode 100644
index 0000000..04e04fb
--- /dev/null
+++ b/drivers/input/keyboard/smsc-ece1099-keypad.c
@@ -0,0 +1,310 @@ 
+/*
+ * SMSC_ECE1099 Keypad driver
+ *
+ * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * 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/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/input/matrix_keypad.h>
+#include <linux/delay.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/smsc.h>
+#include <linux/of_gpio.h>
+#include <linux/of.h>
+
+#define KEYPRESS_TIME          200
+
+struct smsc_keypad {
+	unsigned int last_key_state[16];
+	unsigned int last_col;
+	unsigned int last_key_ms[16];
+	unsigned short *keymap;
+	struct i2c_client *client;
+	struct input_dev *input;
+	int rows, cols;
+	int row_shift;
+	bool no_autorepeat;
+	unsigned        irq;
+	struct device *dev;
+};
+
+static void smsc_kp_report_event(struct smsc_keypad *kp, int col, int temp)
+{
+	struct input_dev *input = kp->input;
+	int j, code, row;
+	unsigned int new_state[16];
+	unsigned int bits_changed;
+	int this_ms;
+
+	for (j = 0; j < kp->rows; j++) {
+		if ((temp & 0x01) != 0x00) {
+			temp = temp >> 1;
+			continue;
+		}
+
+		row = j;
+		new_state[col] =  (1 << row);
+		bits_changed = kp->last_key_state[col] ^ new_state[col];
+		this_ms = jiffies_to_msecs(jiffies);
+		if (bits_changed != 0 || (!bits_changed &&
+				((this_ms - kp->last_key_ms[col]) >= KEYPRESS_TIME))) {
+			code = MATRIX_SCAN_CODE(row, col, kp->row_shift);
+			input_event(input, EV_MSC, MSC_SCAN, code);
+			input_report_key(input, kp->keymap[code], 1);
+			input_report_key(input, kp->keymap[code], 0);
+			kp->last_key_state[col] = new_state[col];
+			if (kp->last_col != col)
+				kp->last_key_state[kp->last_col] = 0;
+			kp->last_key_ms[col] = this_ms;
+		}
+		temp = temp >> 1;
+	}
+}
+
+static void smsc_kp_scan(struct smsc_keypad *kp)
+{
+	struct input_dev *input = kp->input;
+	int i, col, temp;
+
+	smsc_write(kp->dev, SMSC_KP_INT_MASK, 0x00);
+	smsc_write(kp->dev, SMSC_KP_INT_STAT, 0xff);
+
+	/* Scan for row and column */
+	for (i = 0; i < kp->cols; i++) {
+		smsc_write(kp->dev, SMSC_KP_OUT, SMSC_KSO_EVAL + i);
+		/* Read Row Status */
+		smsc_read(kp->dev, SMSC_KP_IN, &temp);
+		if (temp == 0xff)
+			continue;
+
+		col = i;
+		smsc_kp_report_event(kp, col, temp);
+	}
+	input_sync(input);
+
+	smsc_write(kp->dev, SMSC_KP_INT_MASK, 0xff);
+
+	/* Set up Low Power Mode (Wake-up) (0xFB) */
+	smsc_write(kp->dev, SMSC_WKUP_CTRL, SMSC_KP_SET_LOW_PWR);
+
+	/*Enable Keypad Scan (generate interrupt on key press) (0x40)*/
+	smsc_write(kp->dev, SMSC_KP_OUT, SMSC_KSO_ALL_LOW);
+}
+
+static int smsc_keypad_open(struct input_dev *input)
+{
+	struct smsc_keypad *kp = input_get_drvdata(input);
+	int ret;
+
+	ret = smsc_write(kp->dev, SMSC_KP_INT_MASK, 0xff);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static void smsc_keypad_close(struct input_dev *input)
+{
+	struct smsc_keypad *kp = input_get_drvdata(input);
+
+	smsc_write(kp->dev, SMSC_KP_INT_MASK, 0x0);
+}
+
+static irqreturn_t do_kp_irq(int irq, void *_kp)
+{
+	struct smsc_keypad *kp = _kp;
+	int int_status;
+
+	smsc_read(kp->dev, SMSC_KP_INT_STAT, &int_status);
+	if (int_status)
+		smsc_kp_scan(kp);
+
+	return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_OF
+static int __devinit smsc_keypad_parse_dt(struct device *dev,
+				struct smsc_keypad *kp)
+{
+	struct device_node *np = dev->of_node;
+
+	if (!np) {
+		dev_err(dev, "missing DT data");
+		return -EINVAL;
+	}
+
+	of_property_read_u32(np, "keypad,num-rows", &kp->rows);
+	of_property_read_u32(np, "keypad,num-columns", &kp->cols);
+	if (!kp->rows || !kp->cols) {
+		dev_err(dev, "number of keypad rows/columns not specified\n");
+		return -EINVAL;
+	}
+
+	if (of_property_read_bool(np, "linux,input-no-autorepeat"))
+		kp->no_autorepeat = true;
+
+	return 0;
+}
+#else
+static inline int smsc_keypad_parse_dt(struct device *dev,
+				struct smsc_keypad *kp)
+{
+	return -ENOSYS;
+}
+#endif
+
+static int __devinit
+smsc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct input_dev *input;
+	struct smsc_keypad *kp;
+	int ret = 0;
+	int i, max_keys, row_shift;
+	int irq;
+	int addr;
+
+	kp = devm_kzalloc(dev, sizeof(*kp), GFP_KERNEL);
+
+	input = devm_input_allocate_device(dev);
+	if (!kp || !input)
+		ret = -ENOMEM;
+
+	ret = smsc_keypad_parse_dt(dev, kp);
+	if (ret)
+		return ret;
+
+	/* Get the debug Device */
+	kp->input = input;
+	kp->irq = platform_get_irq(pdev, 0);
+	kp->dev = dev;
+
+	/* setup input device */
+	 __set_bit(EV_KEY, input->evbit);
+
+	/* Enable auto repeat feature of Linux input subsystem */
+	if (!kp->no_autorepeat)
+		__set_bit(EV_REP, input->evbit);
+
+	input_set_capability(input, EV_MSC, MSC_SCAN);
+	input->name             = "SMSC Keypad";
+	input->phys             = "smsc_keypad/input0";
+	input->dev.parent       = &pdev->dev;
+	input->id.bustype       = BUS_HOST;
+	input->id.vendor        = 0x0001;
+	input->id.product       = 0x0001;
+	input->id.version       = 0x0003;
+
+	input->open = smsc_keypad_open;
+	input->close = smsc_keypad_close;
+	input_set_drvdata(input, kp);
+
+	/* Mask all GPIO interrupts (0x37-0x3B) */
+	for (addr = SMSC_GPIO_INT_MASK_START;
+			addr < SMSC_GPIO_INT_MASK_START + 4; addr++)
+		smsc_write(dev, addr, 0);
+
+	/* Set all outputs high (0x05-0x09) */
+	for (addr = SMSC_GPIO_DATA_OUT_START;
+			addr < SMSC_GPIO_DATA_OUT_START + 4; addr++)
+		smsc_write(dev, addr, 0xff);
+
+	/* Clear all GPIO interrupts (0x32-0x36) */
+	for (addr = SMSC_GPIO_INT_STAT_START;
+			addr < SMSC_GPIO_INT_STAT_START + 4; addr++)
+		smsc_write(dev, addr, 0xff);
+
+	/* Configure the smsc pins as Keyboard scan Input */
+	for (i = 0; i < kp->rows; i++) {
+		addr = 0x12 + i;
+		smsc_write(dev, addr, SMSC_KP_KSI);
+	}
+
+	/* Configure the smsc pins as Keyboard scan output */
+	for (i = 0; i < kp->cols; i++) {
+		addr = 0x1a + i;
+		smsc_write(dev, addr, SMSC_KP_KSO);
+	}
+
+	smsc_write(dev, SMSC_KP_INT_STAT, SMSC_KP_SET_HIGH);
+	smsc_write(dev, SMSC_WKUP_CTRL, SMSC_KP_SET_LOW_PWR);
+	smsc_write(dev, SMSC_KP_OUT, SMSC_KSO_ALL_LOW);
+
+	row_shift = get_count_order(kp->cols);
+	max_keys = kp->rows << row_shift;
+
+	kp->row_shift = row_shift;
+	kp->keymap = devm_kzalloc(dev, max_keys * sizeof(kp->keymap[0]),
+					GFP_KERNEL);
+	if (!kp->keymap) {
+		dev_err(dev, "Not enough memory for keymap\n");
+		return -ENOMEM;
+	}
+
+	ret = matrix_keypad_build_keymap(NULL, NULL, kp->rows,
+			kp->cols, kp->keymap, input);
+	if (ret) {
+		dev_err(dev, "failed to build keymap\n");
+		return ret;
+	}
+
+	/*
+	* This ISR will always execute in kernel thread context because of
+	* the need to access the SMSC over the I2C bus.
+	*/
+	ret = devm_request_threaded_irq(dev, kp->irq, NULL, do_kp_irq,
+			IRQF_TRIGGER_FALLING | IRQF_ONESHOT, pdev->name, kp);
+	if (ret) {
+		dev_dbg(dev, "request_irq failed for irq no=%d\n",
+			irq);
+		return ret;
+	}
+
+	ret = input_register_device(input);
+	if (ret) {
+		dev_err(kp->dev,
+			"Unable to register twl4030 keypad device\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int __devexit smsc_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static const struct of_device_id smsc_keypad_dt_match[] = {
+	{ .compatible = "smsc,keypad" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, smsc_keypad_dt_match);
+
+static struct platform_driver smsc_driver = {
+	.driver = {
+		.name	= "smsc-keypad",
+		.of_match_table = of_match_ptr(smsc_keypad_dt_match),
+		.owner  = THIS_MODULE,
+	},
+	.probe		= smsc_probe,
+	.remove		= __devexit_p(smsc_remove),
+};
+
+module_platform_driver(smsc_driver);
+
+MODULE_AUTHOR("G Kondaiah Manjunath <[e-mail]>");
+MODULE_DESCRIPTION("SMSC ECE1099 Keypad driver");
+MODULE_LICENSE("GPL v2");