diff mbox

[1/5] drivers: input: keyboard: st-keyscan: add keyscan driver

Message ID 1393990772-9567-2-git-send-email-gabriel.fernandez@st.com
State Superseded, archived
Headers show

Commit Message

Gabriel Fernandez March 5, 2014, 3:39 a.m. UTC
This patch adds ST Keyscan driver to use the keypad hw a subset
of ST boards provide. Specific board setup will be put in the
given dt.

Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com>
Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
---
 .../devicetree/bindings/input/st-keypad.txt        |  50 ++++
 drivers/input/keyboard/Kconfig                     |  12 +
 drivers/input/keyboard/Makefile                    |   1 +
 drivers/input/keyboard/st-keyscan.c                | 323 +++++++++++++++++++++
 4 files changed, 386 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/input/st-keypad.txt
 create mode 100644 drivers/input/keyboard/st-keyscan.c

Comments

Dmitry Torokhov March 5, 2014, 6:46 a.m. UTC | #1
Hi Gabriel,

On Wed, Mar 05, 2014 at 04:39:28AM +0100, Gabriel FERNANDEZ wrote:
> This patch adds ST Keyscan driver to use the keypad hw a subset
> of ST boards provide. Specific board setup will be put in the
> given dt.
> 
> Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com>
> Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
> ---
>  .../devicetree/bindings/input/st-keypad.txt        |  50 ++++
>  drivers/input/keyboard/Kconfig                     |  12 +
>  drivers/input/keyboard/Makefile                    |   1 +
>  drivers/input/keyboard/st-keyscan.c                | 323 +++++++++++++++++++++
>  4 files changed, 386 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/input/st-keypad.txt
>  create mode 100644 drivers/input/keyboard/st-keyscan.c
> 
> diff --git a/Documentation/devicetree/bindings/input/st-keypad.txt b/Documentation/devicetree/bindings/input/st-keypad.txt
> new file mode 100644
> index 0000000..63eb07a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/st-keypad.txt
> @@ -0,0 +1,50 @@
> +* ST Keypad controller device tree bindings
> +
> +The ST keypad controller device tree binding is based on the
> +matrix-keymap.
> +
> +Required properties:
> +
> +- compatible: "st,keypad"
> +
> +- reg: Register base address of st-keypad controler.
> +
> +- interrupts: Interrupt numberof st-keypad controler.
> +
> +- clocks: Must contain one entry, for the module clock.
> +  See ../clocks/clock-bindings.txt for details.
> +
> +- pinctrl-0: Should specify pin control groups used for this controller.
> +
> +- pinctrl-names: Should contain only one value - "default".
> +
> +- linux,keymap: The keymap for keys as described in the binding document
> +  devicetree/bindings/input/matrix-keymap.txt.
> +
> +- keypad,num-rows: Number of row lines connected to the keypad controller.
> +
> +- keypad,num-columns: Number of column lines connected to the keypad
> +  controller.
> +
> +- st,debounce_us: Debouncing interval time in microseconds
> +
> +
> +Example:
> +
> +keyscan: keyscan@fe4b0000 {
> +	compatible = "st,keypad";
> +	reg = <0xfe4b0000 0x2000>;
> +	interrupts = <GIC_SPI 212 IRQ_TYPE_NONE>;
> +	clocks	= <&CLK_SYSIN>;
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&pinctrl_keyscan>;
> +
> +	keypad,num-rows = <4>;
> +	keypad,num-columns = <4>;
> +	st,debounce_us = <5000>;
> +	linux,keymap = < /* in0	in1	in2	in3 */
> +		KEY_F13 KEY_F9  KEY_F5 KEY_F1		/* out0 */
> +		KEY_F14 KEY_F10 KEY_F6 KEY_F2		/* out1 */
> +		KEY_F15 KEY_F11 KEY_F7 KEY_F3		/* out2 */
> +		KEY_F16 KEY_F12 KEY_F8 KEY_F4 >;	/* out3 */
> +};
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index a673c9f..9e29125 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -512,6 +512,18 @@ config KEYBOARD_STOWAWAY
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called stowaway.
>  
> +config KEYBOARD_ST_KEYSCAN
> +	tristate "STMicroelectronics keyscan support"
> +	depends on ARCH_STI
> +	select INPUT_EVDEV
> +	select INPUT_MATRIXKMAP
> +	help
> +	  Say Y here if you want to use a keypad attached to the keyscan block
> +	  on some STMicroelectronics SoC devices.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called stm-keyscan.
> +
>  config KEYBOARD_SUNKBD
>  	tristate "Sun Type 4 and Type 5 keyboard"
>  	select SERIO
> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> index a699b61..5fd020a 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -50,6 +50,7 @@ obj-$(CONFIG_KEYBOARD_SH_KEYSC)		+= sh_keysc.o
>  obj-$(CONFIG_KEYBOARD_SPEAR)		+= spear-keyboard.o
>  obj-$(CONFIG_KEYBOARD_STMPE)		+= stmpe-keypad.o
>  obj-$(CONFIG_KEYBOARD_STOWAWAY)		+= stowaway.o
> +obj-$(CONFIG_KEYBOARD_ST_KEYSCAN)	+= st-keyscan.o
>  obj-$(CONFIG_KEYBOARD_SUNKBD)		+= sunkbd.o
>  obj-$(CONFIG_KEYBOARD_TC3589X)		+= tc3589x-keypad.o
>  obj-$(CONFIG_KEYBOARD_TEGRA)		+= tegra-kbc.o
> diff --git a/drivers/input/keyboard/st-keyscan.c b/drivers/input/keyboard/st-keyscan.c
> new file mode 100644
> index 0000000..606cc19
> --- /dev/null
> +++ b/drivers/input/keyboard/st-keyscan.c
> @@ -0,0 +1,323 @@
> +/*
> + * STMicroelectronics Key Scanning driver
> + *
> + * Copyright (c) 2014 STMicroelectonics Ltd.
> + * Author: Stuart Menefy <stuart.menefy@st.com>
> + *
> + * Based on sh_keysc.c, copyright 2008 Magnus Damm
> + *
> + * 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/interrupt.h>
> +#include <linux/platform_device.h>
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <linux/input/matrix_keypad.h>
> +
> +#define ST_KEYSCAN_MAXKEYS 16
> +
> +#define KEYSCAN_CONFIG_OFF		0x000
> +#define KEYSCAN_CONFIG_ENABLE		1
> +#define KEYSCAN_DEBOUNCE_TIME_OFF	0x004
> +#define KEYSCAN_MATRIX_STATE_OFF	0x008
> +#define KEYSCAN_MATRIX_DIM_OFF		0x00c
> +#define KEYSCAN_MATRIX_DIM_X_SHIFT	0
> +#define KEYSCAN_MATRIX_DIM_Y_SHIFT	2
> +
> +struct keypad_platform_data {
> +	const struct matrix_keymap_data *keymap_data;
> +	unsigned int num_out_pads;
> +	unsigned int num_in_pads;
> +	unsigned int debounce_us;
> +};
> +
> +struct keyscan_priv {
> +	void __iomem *base;
> +	int irq;
> +	struct clk *clk;
> +	struct input_dev *input_dev;
> +	struct keypad_platform_data *config;
> +	unsigned int last_state;
> +	u32 keycodes[ST_KEYSCAN_MAXKEYS];
> +};
> +
> +static irqreturn_t keyscan_isr(int irq, void *dev_id)
> +{
> +	struct platform_device *pdev = dev_id;
> +	struct keyscan_priv *priv = platform_get_drvdata(pdev);
> +	int state;
> +	int change;
> +
> +	state = readl(priv->base + KEYSCAN_MATRIX_STATE_OFF) & 0xffff;
> +	change = priv->last_state ^ state;
> +
> +	while (change) {
> +		int scancode = __ffs(change);
> +		int down = state & (1 << scancode);
> +
> +		input_report_key(priv->input_dev, priv->keycodes[scancode],
> +				 down);
> +		change ^= 1 << scancode;
> +	};
> +
> +	input_sync(priv->input_dev);
> +
> +	priv->last_state = state;
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void keyscan_start(struct keyscan_priv *priv)
> +{
> +	clk_enable(priv->clk);
> +
> +	writel(priv->config->debounce_us * (clk_get_rate(priv->clk) / 1000000),
> +	       priv->base + KEYSCAN_DEBOUNCE_TIME_OFF);
> +
> +	writel(((priv->config->num_in_pads - 1) << KEYSCAN_MATRIX_DIM_X_SHIFT) |
> +	       ((priv->config->num_out_pads - 1) << KEYSCAN_MATRIX_DIM_Y_SHIFT),
> +	       priv->base + KEYSCAN_MATRIX_DIM_OFF);
> +
> +	writel(KEYSCAN_CONFIG_ENABLE, priv->base + KEYSCAN_CONFIG_OFF);
> +}
> +
> +static void keyscan_stop(struct keyscan_priv *priv)
> +{
> +	writel(0, priv->base + KEYSCAN_CONFIG_OFF);
> +
> +	clk_disable(priv->clk);
> +}
> +
> +static int keypad_matrix_key_parse_dt(struct keyscan_priv *st_kp)
> +{
> +	struct device *dev = st_kp->input_dev->dev.parent;
> +	struct device_node *np = dev->of_node;
> +	struct keypad_platform_data *pdata;
> +	int error;
> +
> +	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
> +	if (!pdata) {
> +		dev_err(dev, "failed to allocate driver pdata\n");
> +		return -ENOMEM;
> +	}
> +
> +	error = matrix_keypad_parse_of_params(dev, &pdata->num_out_pads,
> +			&pdata->num_in_pads);
> +	if (error) {
> +		dev_err(dev, "failed to parse keypad params\n");
> +		return error;
> +	}
> +
> +	of_property_read_u32(np, "st,debounce_us", &pdata->debounce_us);
> +
> +	st_kp->config = pdata;
> +
> +	dev_info(dev, "rows=%d col=%d debounce=%d\n",
> +			pdata->num_out_pads,
> +			pdata->num_in_pads,
> +			pdata->debounce_us);
> +
> +	error = of_property_read_u32_array(np, "linux,keymap",
> +					st_kp->keycodes, ST_KEYSCAN_MAXKEYS);
> +	if (error) {
> +		dev_err(dev, "failed to parse keymap\n");
> +		return error;
> +	}

Please use standard format for matrix keymap so that you can use
matrix_keypad_build_keymap().

> +
> +	return 0;
> +}
> +
> +static int __init keyscan_probe(struct platform_device *pdev)
> +{
> +	struct keypad_platform_data *pdata =
> +		dev_get_platdata(&pdev->dev);

const struct ...

> +	struct keyscan_priv *st_kp;
> +	struct input_dev *input_dev;
> +	struct device *dev = &pdev->dev;
> +	struct resource *res;
> +	int len;
> +	int error;
> +	int i;
> +
> +	if (!pdata && !pdev->dev.of_node) {
> +		dev_err(&pdev->dev, "no keymap defined\n");
> +		return -EINVAL;
> +	}
> +
> +	st_kp = devm_kzalloc(dev, sizeof(*st_kp), GFP_KERNEL);
> +	if (!st_kp) {
> +		dev_err(dev, "failed to allocate driver data\n");
> +		return -ENOMEM;
> +	}
> +	st_kp->config = pdata;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(dev, "no I/O memory specified\n");
> +		return -ENXIO;
> +	}
> +
> +	len = resource_size(res);
> +	if (!devm_request_mem_region(dev, res->start, len, pdev->name)) {
> +		dev_err(dev, "failed to reserve I/O memory\n");
> +		return -EBUSY;
> +	}
> +
> +	st_kp->base = devm_ioremap_nocache(dev, res->start, len);
> +	if (st_kp->base == NULL) {
> +		dev_err(dev, "failed to remap I/O memory\n");
> +		return -ENXIO;
> +	}
> +
> +	st_kp->irq = platform_get_irq(pdev, 0);
> +	if (st_kp->irq < 0) {
> +		dev_err(dev, "no IRQ specified\n");
> +		return -ENXIO;
> +	}
> +
> +	error = devm_request_irq(dev, st_kp->irq, keyscan_isr, 0,
> +				 pdev->name, pdev);
> +	if (error) {
> +		dev_err(dev, "failed to request IRQ\n");
> +		return error;
> +	}
> +
> +	input_dev = devm_input_allocate_device(&pdev->dev);
> +	if (!input_dev) {
> +		dev_err(&pdev->dev, "failed to allocate the input device\n");
> +		return -ENOMEM;
> +	}
> +
> +	st_kp->clk = devm_clk_get(dev, NULL);
> +	if (IS_ERR(st_kp->clk)) {
> +		dev_err(dev, "cannot get clock");
> +		return PTR_ERR(st_kp->clk);
> +	}
> +
> +	input_dev = input_allocate_device();
> +	if (!input_dev) {
> +		dev_err(dev, "failed to allocate input device\n");
> +		return -ENOMEM;
> +	}

You already allocated it once a few lines above.

> +	st_kp->input_dev = input_dev;
> +
> +	input_dev->name = pdev->name;
> +	input_dev->phys = "keyscan-keys/input0";
> +	input_dev->dev.parent = dev;
> +
> +	input_dev->id.bustype = BUS_HOST;
> +	input_dev->id.vendor = 0x0001;
> +	input_dev->id.product = 0x0001;
> +	input_dev->id.version = 0x0100;
> +
> +	if (!pdata) {
> +		error = keypad_matrix_key_parse_dt(st_kp);
> +		if (error)
> +			return error;
> +		pdata = st_kp->config;
> +	}
> +
> +	input_dev->keycode = st_kp->keycodes;
> +	input_dev->keycodesize = sizeof(st_kp->keycodes[0]);
> +	input_dev->keycodemax = ARRAY_SIZE(st_kp->keycodes);
> +
> +	for (i = 0; i < ST_KEYSCAN_MAXKEYS; i++)
> +		input_set_capability(input_dev, EV_KEY, st_kp->keycodes[i]);
> +	__clear_bit(KEY_RESERVED, input_dev->keybit);
> +
> +	error = input_register_device(input_dev);
> +	if (error) {
> +		dev_err(dev, "failed to register input device\n");
> +		input_free_device(input_dev);
> +		platform_set_drvdata(pdev, NULL);
> +		return error;
> +	}
> +
> +	platform_set_drvdata(pdev, st_kp);
> +
> +	keyscan_start(st_kp);
> +
> +	device_set_wakeup_capable(&pdev->dev, 1);
> +
> +	return 0;
> +}
> +
> +static int __exit keyscan_remove(struct platform_device *pdev)

Why is this marked as __exit? I can unbind device from driver without
unloading module (via sysfs).

> +{
> +	struct keyscan_priv *priv = platform_get_drvdata(pdev);
> +
> +	keyscan_stop(priv);

Call to keyscan_stop() shoudl go into keyscan_close() implementation.

> +
> +	input_unregister_device(priv->input_dev);

Not needed since you are trying to use devres-managed input device.

> +	platform_set_drvdata(pdev, NULL);

Not needed. In fact, if you move keyscan_stop() into keyscan_close() you
should be able to get rid of keyscan_remove().

> +
> +	return 0;
> +}
> +
> +static int keyscan_suspend(struct device *dev)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct keyscan_priv *priv = platform_get_drvdata(pdev);
> +
> +	if (device_may_wakeup(dev))
> +		enable_irq_wake(priv->irq);
> +	else
> +		keyscan_stop(priv);
> +
> +	return 0;
> +}
> +
> +static int keyscan_resume(struct device *dev)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct keyscan_priv *priv = platform_get_drvdata(pdev);
> +
> +	if (device_may_wakeup(dev))
> +		disable_irq_wake(priv->irq);
> +	else
> +		keyscan_start(priv);
> +
> +	return 0;
> +}

Guard suspend/resume with CONFIG_PM_SLEEP?

> +
> +static const struct dev_pm_ops keyscan_dev_pm_ops = {
> +	.suspend = keyscan_suspend,
> +	.resume = keyscan_resume,
> +};

Make it SIMPLE_DEV_PM_OPS().

> +
> +static const struct of_device_id keyscan_of_match[] = {
> +	{ .compatible = "st,keypad" },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, keyscan_of_match);
> +
> +__refdata struct platform_driver keyscan_device_driver = {

What is this refdata business?

> +	.probe		= keyscan_probe,
> +	.remove		= __exit_p(keyscan_remove),
> +	.driver		= {
> +		.name	= "st-keyscan",
> +		.pm	= &keyscan_dev_pm_ops,
> +		.of_match_table = of_match_ptr(keyscan_of_match),
> +	}
> +};
> +
> +static int __init keyscan_init(void)
> +{
> +	return platform_driver_register(&keyscan_device_driver);
> +}
> +
> +static void __exit keyscan_exit(void)
> +{
> +	platform_driver_unregister(&keyscan_device_driver);
> +}
> +
> +module_init(keyscan_init);
> +module_exit(keyscan_exit);

I think we have module_platform_drriver() for this.

> +
> +MODULE_AUTHOR("Stuart Menefy <stuart.menefy@st.com>");
> +MODULE_DESCRIPTION("STMicroelectronics keyscan device driver");
> +MODULE_LICENSE("GPL");
> -- 
> 1.9.0
> 

Thanks.
Lee Jones March 10, 2014, 11:48 a.m. UTC | #2
Hi Gabi,

Sorry for the delay. It was a hectic week last week.

As promised:

> This patch adds ST Keyscan driver to use the keypad hw a subset
> of ST boards provide. Specific board setup will be put in the
> given dt.
> 
> Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com>
> Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>

Are you sure these are in the correct order?

What is the history of this commit?

> ---
>  .../devicetree/bindings/input/st-keypad.txt        |  50 ++++

This should be submitted as a seperate patch.

>  drivers/input/keyboard/Kconfig                     |  12 +
>  drivers/input/keyboard/Makefile                    |   1 +
>  drivers/input/keyboard/st-keyscan.c                | 323 +++++++++++++++++++++
>  4 files changed, 386 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/input/st-keypad.txt
>  create mode 100644 drivers/input/keyboard/st-keyscan.c
> 
> diff --git a/Documentation/devicetree/bindings/input/st-keypad.txt b/Documentation/devicetree/bindings/input/st-keypad.txt
> new file mode 100644
> index 0000000..63eb07a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/st-keypad.txt
> @@ -0,0 +1,50 @@
> +* ST Keypad controller device tree bindings

s/device tree/Device Tree

> +
> +The ST keypad controller device tree binding is based on the

As above.

> +matrix-keymap.
> +
> +Required properties:
> +
> +- compatible: "st,keypad"

I think there will be subsequent st,keypad drivers? Is there any way
we can make this compatible string more specific to _this_ device?

st,stih4xx-keypad?

> +- reg: Register base address of st-keypad controler.

s/address/address and size AND s/controler/controller

> +- interrupts: Interrupt numberof st-keypad controler.

s/numberof/number for the

> +- clocks: Must contain one entry, for the module clock.
> +  See ../clocks/clock-bindings.txt for details.

Great!

> +- pinctrl-0: Should specify pin control groups used for this controller.
> +
> +- pinctrl-names: Should contain only one value - "default".

Like to ../pinctrl/pinctrl-bindings.txt

> +- linux,keymap: The keymap for keys as described in the binding document
> +  devicetree/bindings/input/matrix-keymap.txt.
> +
> +- keypad,num-rows: Number of row lines connected to the keypad controller.
> +
> +- keypad,num-columns: Number of column lines connected to the keypad
> +  controller.
> +
> +- st,debounce_us: Debouncing interval time in microseconds

I'm sure there will be a shared binding for de-bounce.

If not, there certainly should be.

> +
> +

Superfluous new lines.

> +Example:
> +
> +keyscan: keyscan@fe4b0000 {
> +	compatible = "st,keypad";

Is there any way we can make this more specific to _this_ IP?

> +	reg = <0xfe4b0000 0x2000>;
> +	interrupts = <GIC_SPI 212 IRQ_TYPE_NONE>;
> +	clocks	= <&CLK_SYSIN>;
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&pinctrl_keyscan>;
> +
> +	keypad,num-rows = <4>;
> +	keypad,num-columns = <4>;
> +	st,debounce_us = <5000>;
> +	linux,keymap = < /* in0	in1	in2	in3 */

Do these line up in the file? I know Git can be a bit funny about this
sometimes.

> +		KEY_F13 KEY_F9  KEY_F5 KEY_F1		/* out0 */
> +		KEY_F14 KEY_F10 KEY_F6 KEY_F2		/* out1 */
> +		KEY_F15 KEY_F11 KEY_F7 KEY_F3		/* out2 */
> +		KEY_F16 KEY_F12 KEY_F8 KEY_F4 >;	/* out3 */
> +};
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index a673c9f..9e29125 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -512,6 +512,18 @@ config KEYBOARD_STOWAWAY
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called stowaway.
>  
> +config KEYBOARD_ST_KEYSCAN
> +	tristate "STMicroelectronics keyscan support"
> +	depends on ARCH_STI
> +	select INPUT_EVDEV
> +	select INPUT_MATRIXKMAP
> +	help
> +	  Say Y here if you want to use a keypad attached to the keyscan block
> +	  on some STMicroelectronics SoC devices.

Might be worth mentioning which ones.

> +	  To compile this driver as a module, choose M here: the
> +	  module will be called stm-keyscan.
> +
>  config KEYBOARD_SUNKBD
>  	tristate "Sun Type 4 and Type 5 keyboard"
>  	select SERIO
> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> index a699b61..5fd020a 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -50,6 +50,7 @@ obj-$(CONFIG_KEYBOARD_SH_KEYSC)		+= sh_keysc.o
>  obj-$(CONFIG_KEYBOARD_SPEAR)		+= spear-keyboard.o
>  obj-$(CONFIG_KEYBOARD_STMPE)		+= stmpe-keypad.o
>  obj-$(CONFIG_KEYBOARD_STOWAWAY)		+= stowaway.o
> +obj-$(CONFIG_KEYBOARD_ST_KEYSCAN)	+= st-keyscan.o
>  obj-$(CONFIG_KEYBOARD_SUNKBD)		+= sunkbd.o
>  obj-$(CONFIG_KEYBOARD_TC3589X)		+= tc3589x-keypad.o
>  obj-$(CONFIG_KEYBOARD_TEGRA)		+= tegra-kbc.o
> diff --git a/drivers/input/keyboard/st-keyscan.c b/drivers/input/keyboard/st-keyscan.c
> new file mode 100644
> index 0000000..606cc19
> --- /dev/null
> +++ b/drivers/input/keyboard/st-keyscan.c
> @@ -0,0 +1,323 @@
> +/*
> + * STMicroelectronics Key Scanning driver
> + *
> + * Copyright (c) 2014 STMicroelectonics Ltd.
> + * Author: Stuart Menefy <stuart.menefy@st.com>
> + *
> + * Based on sh_keysc.c, copyright 2008 Magnus Damm

Did sh_keysc.c ever exist in Mainline?

> + * 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/interrupt.h>
> +#include <linux/platform_device.h>
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <linux/input/matrix_keypad.h>
> +
> +#define ST_KEYSCAN_MAXKEYS 16
> +
> +#define KEYSCAN_CONFIG_OFF		0x000
> +#define KEYSCAN_CONFIG_ENABLE		1

0x001?

> +#define KEYSCAN_DEBOUNCE_TIME_OFF	0x004
> +#define KEYSCAN_MATRIX_STATE_OFF	0x008
> +#define KEYSCAN_MATRIX_DIM_OFF		0x00c

Odd that these are 3 digit padded? Is there a reason for that?

> +#define KEYSCAN_MATRIX_DIM_X_SHIFT	0
> +#define KEYSCAN_MATRIX_DIM_Y_SHIFT	2

For all 'ST_KEYSCAN_...'?

> +struct keypad_platform_data {
> +	const struct matrix_keymap_data *keymap_data;
> +	unsigned int num_out_pads;
> +	unsigned int num_in_pads;
> +	unsigned int debounce_us;
> +};
> +
> +struct keyscan_priv {
> +	void __iomem *base;
> +	int irq;
> +	struct clk *clk;
> +	struct input_dev *input_dev;
> +	struct keypad_platform_data *config;
> +	unsigned int last_state;
> +	u32 keycodes[ST_KEYSCAN_MAXKEYS];

Seems odd to limit this. Can't the information come from DT
i.e. keypad,num-rows and keypad,num-columns?

> +};
> +
> +static irqreturn_t keyscan_isr(int irq, void *dev_id)
> +{
> +	struct platform_device *pdev = dev_id;
> +	struct keyscan_priv *priv = platform_get_drvdata(pdev);
> +	int state;
> +	int change;
> +
> +	state = readl(priv->base + KEYSCAN_MATRIX_STATE_OFF) & 0xffff;
> +	change = priv->last_state ^ state;
> +
> +	while (change) {
> +		int scancode = __ffs(change);
> +		int down = state & (1 << scancode);

int down = state & BIT(scancode);

> +		input_report_key(priv->input_dev, priv->keycodes[scancode],
> +				 down);
> +		change ^= 1 << scancode;

change ^= BIT(scancode);

> +	};
> +
> +	input_sync(priv->input_dev);
> +
> +	priv->last_state = state;
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void keyscan_start(struct keyscan_priv *priv)
> +{
> +	clk_enable(priv->clk);
> +
> +	writel(priv->config->debounce_us * (clk_get_rate(priv->clk) / 1000000),
> +	       priv->base + KEYSCAN_DEBOUNCE_TIME_OFF);
> +
> +	writel(((priv->config->num_in_pads - 1) << KEYSCAN_MATRIX_DIM_X_SHIFT) |
> +	       ((priv->config->num_out_pads - 1) << KEYSCAN_MATRIX_DIM_Y_SHIFT),
> +	       priv->base + KEYSCAN_MATRIX_DIM_OFF);
> +
> +	writel(KEYSCAN_CONFIG_ENABLE, priv->base + KEYSCAN_CONFIG_OFF);
> +}
> +
> +static void keyscan_stop(struct keyscan_priv *priv)
> +{
> +	writel(0, priv->base + KEYSCAN_CONFIG_OFF);
> +
> +	clk_disable(priv->clk);
> +}
> +
> +static int keypad_matrix_key_parse_dt(struct keyscan_priv *st_kp)
> +{
> +	struct device *dev = st_kp->input_dev->dev.parent;
> +	struct device_node *np = dev->of_node;
> +	struct keypad_platform_data *pdata;
> +	int error;
> +
> +	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
> +	if (!pdata) {
> +		dev_err(dev, "failed to allocate driver pdata\n");

If the system is OOM, this sort of error message will be pretty
redundant. Just return -ENOMEM instead.

> +		return -ENOMEM;
> +	}
> +
> +	error = matrix_keypad_parse_of_params(dev, &pdata->num_out_pads,
> +			&pdata->num_in_pads);
> +	if (error) {
> +		dev_err(dev, "failed to parse keypad params\n");
> +		return error;

Nit: It's pretty unusual to use this for a standard error handling
variable. Consider 'ret' or 'err' as a replacement.

> +	}
> +
> +	of_property_read_u32(np, "st,debounce_us", &pdata->debounce_us);

Isn't this a required property? Might be worth checking the return
value if so.

> +	st_kp->config = pdata;
> +
> +	dev_info(dev, "rows=%d col=%d debounce=%d\n",
> +			pdata->num_out_pads,
> +			pdata->num_in_pads,
> +			pdata->debounce_us);

Might be worth moving this down passed the final point of failure.

> +	error = of_property_read_u32_array(np, "linux,keymap",
> +					st_kp->keycodes, ST_KEYSCAN_MAXKEYS);
> +	if (error) {
> +		dev_err(dev, "failed to parse keymap\n");
> +		return error;
> +	}
> +
> +	return 0;
> +}
> +
> +static int __init keyscan_probe(struct platform_device *pdev)
> +{
> +	struct keypad_platform_data *pdata =
> +		dev_get_platdata(&pdev->dev);

Do we really support platform data still?

> +	struct keyscan_priv *st_kp;
> +	struct input_dev *input_dev;
> +	struct device *dev = &pdev->dev;

dev and pdev are used randomly in probe(). Just remove the dev
de-reference and use &pdev->dev exclusively.

It's pretty common to de-reference 'np = pdev->dev.of_node' though.

> +	struct resource *res;
> +	int len;
> +	int error;
> +	int i;
> +
> +	if (!pdata && !pdev->dev.of_node) {
> +		dev_err(&pdev->dev, "no keymap defined\n");
> +		return -EINVAL;
> +	}
> +
> +	st_kp = devm_kzalloc(dev, sizeof(*st_kp), GFP_KERNEL);
> +	if (!st_kp) {
> +		dev_err(dev, "failed to allocate driver data\n");
> +		return -ENOMEM;

I wouldn't print any messages on -ENOMEM personally. It's not a driver
failure per se, but a system one where the user will soon be notified.

> +	}
> +	st_kp->config = pdata;

You only want to do this in the !np case.

> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(dev, "no I/O memory specified\n");
> +		return -ENXIO;
> +	}
> +
> +	len = resource_size(res);
> +	if (!devm_request_mem_region(dev, res->start, len, pdev->name)) {
> +		dev_err(dev, "failed to reserve I/O memory\n");
> +		return -EBUSY;
> +	}
> +
> +	st_kp->base = devm_ioremap_nocache(dev, res->start, len);
> +	if (st_kp->base == NULL) {
> +		dev_err(dev, "failed to remap I/O memory\n");
> +		return -ENXIO;
> +	}

Replace the two above with devm_ioremap_resource().

Make sure the IORESOURCE_CACHEABLE is set.

> +	st_kp->irq = platform_get_irq(pdev, 0);
> +	if (st_kp->irq < 0) {
> +		dev_err(dev, "no IRQ specified\n");
> +		return -ENXIO;

No such device or address, are you sure?

Perhaps -EINVAL would be better, as one should be specified.

> +	}
> +
> +	error = devm_request_irq(dev, st_kp->irq, keyscan_isr, 0,
> +				 pdev->name, pdev);
> +	if (error) {
> +		dev_err(dev, "failed to request IRQ\n");
> +		return error;
> +	}
> +
> +	input_dev = devm_input_allocate_device(&pdev->dev);
> +	if (!input_dev) {
> +		dev_err(&pdev->dev, "failed to allocate the input device\n");
> +		return -ENOMEM;
> +	}
> +
> +	st_kp->clk = devm_clk_get(dev, NULL);
> +	if (IS_ERR(st_kp->clk)) {
> +		dev_err(dev, "cannot get clock");
> +		return PTR_ERR(st_kp->clk);
> +	}
> +
> +	input_dev = input_allocate_device();
> +	if (!input_dev) {
> +		dev_err(dev, "failed to allocate input device\n");
> +		return -ENOMEM;
> +	}

Wasn't this done already?

> +	st_kp->input_dev = input_dev;
> +
> +	input_dev->name = pdev->name;
> +	input_dev->phys = "keyscan-keys/input0";
> +	input_dev->dev.parent = dev;
> +
> +	input_dev->id.bustype = BUS_HOST;
> +	input_dev->id.vendor = 0x0001;
> +	input_dev->id.product = 0x0001;
> +	input_dev->id.version = 0x0100;

Any chance we can #define these?

> +	if (!pdata) {
> +		error = keypad_matrix_key_parse_dt(st_kp);
> +		if (error)
> +			return error;
> +		pdata = st_kp->config;

Is pdata used after this?

> +	}
> +
> +	input_dev->keycode = st_kp->keycodes;
> +	input_dev->keycodesize = sizeof(st_kp->keycodes[0]);
> +	input_dev->keycodemax = ARRAY_SIZE(st_kp->keycodes);
> +
> +	for (i = 0; i < ST_KEYSCAN_MAXKEYS; i++)
> +		input_set_capability(input_dev, EV_KEY, st_kp->keycodes[i]);
> +	__clear_bit(KEY_RESERVED, input_dev->keybit);
> +
> +	error = input_register_device(input_dev);
> +	if (error) {
> +		dev_err(dev, "failed to register input device\n");
> +		input_free_device(input_dev);
> +		platform_set_drvdata(pdev, NULL);

You don't need to do this anymore. It's taken care of elsewhere.

> +		return error;
> +	}
> +
> +	platform_set_drvdata(pdev, st_kp);
> +
> +	keyscan_start(st_kp);
> +
> +	device_set_wakeup_capable(&pdev->dev, 1);
> +
> +	return 0;
> +}
> +
> +static int __exit keyscan_remove(struct platform_device *pdev)
> +{
> +	struct keyscan_priv *priv = platform_get_drvdata(pdev);
> +
> +	keyscan_stop(priv);
> +
> +	input_unregister_device(priv->input_dev);
> +	platform_set_drvdata(pdev, NULL);
> +
> +	return 0;

I already saw that Dmitry commented on the rest of the file.

<snip>
Dmitry Torokhov March 10, 2014, 3:28 p.m. UTC | #3
Hi Lee,

On Mon, Mar 10, 2014 at 11:48:19AM +0000, Lee Jones wrote:
> Hi Gabi,
> 
> Sorry for the delay. It was a hectic week last week.
> 
> As promised:
> 
> > This patch adds ST Keyscan driver to use the keypad hw a subset
> > of ST boards provide. Specific board setup will be put in the
> > given dt.
> > 
> > Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com>
> > Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
> 
> Are you sure these are in the correct order?
> 
> What is the history of this commit?
> 
> > ---
> >  .../devicetree/bindings/input/st-keypad.txt        |  50 ++++
> 
> This should be submitted as a seperate patch.

Why do we have such requirement? To me it would make more sense to add
binding documentation in the same commit as the code that uses these
bindings.

[...]

> > +
> > +	error = matrix_keypad_parse_of_params(dev, &pdata->num_out_pads,
> > +			&pdata->num_in_pads);
> > +	if (error) {
> > +		dev_err(dev, "failed to parse keypad params\n");
> > +		return error;
> 
> Nit: It's pretty unusual to use this for a standard error handling
> variable. Consider 'ret' or 'err' as a replacement.

I like "error", in fact there are a lot of these in input. I use "error" for
data that is only returned from error path and "retval" when the same
variable is returned in both success and error paths.

> > +
> > +	input_dev->id.bustype = BUS_HOST;
> > +	input_dev->id.vendor = 0x0001;
> > +	input_dev->id.product = 0x0001;
> > +	input_dev->id.version = 0x0100;
> 
> Any chance we can #define these?

Even better would be not use 0x0001 as vendor as there (unfortunately)
quite a few other drivers use it already. Either omit or chose something
else. Does ST have PCI or USB VID assigned?

Thanks.
Lee Jones March 10, 2014, 3:38 p.m. UTC | #4
> > > This patch adds ST Keyscan driver to use the keypad hw a subset
> > > of ST boards provide. Specific board setup will be put in the
> > > given dt.
> > > 
> > > Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com>
> > > Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
> > 
> > Are you sure these are in the correct order?
> > 
> > What is the history of this commit?
> > 
> > > ---
> > >  .../devicetree/bindings/input/st-keypad.txt        |  50 ++++
> > 
> > This should be submitted as a seperate patch.
> 
> Why do we have such requirement? To me it would make more sense to add
> binding documentation in the same commit as the code that uses these
> bindings.

I'm inclined to agree with you and that's actually how we used to do
it, but a decision was made by the DT guys at one of the Kernel
Summits to submit Documentation as a separate patch.

> [...]
> 
> > > +
> > > +	error = matrix_keypad_parse_of_params(dev, &pdata->num_out_pads,
> > > +			&pdata->num_in_pads);
> > > +	if (error) {
> > > +		dev_err(dev, "failed to parse keypad params\n");
> > > +		return error;
> > 
> > Nit: It's pretty unusual to use this for a standard error handling
> > variable. Consider 'ret' or 'err' as a replacement.
> 
> I like "error", in fact there are a lot of these in input. I use "error" for
> data that is only returned from error path and "retval" when the same
> variable is returned in both success and error paths.

If that's your preference then I'm cool with it too. Scrap my comment.

[...]
Dmitry Torokhov March 10, 2014, 3:58 p.m. UTC | #5
On Mon, Mar 10, 2014 at 03:38:15PM +0000, Lee Jones wrote:
> > > > This patch adds ST Keyscan driver to use the keypad hw a subset
> > > > of ST boards provide. Specific board setup will be put in the
> > > > given dt.
> > > > 
> > > > Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com>
> > > > Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
> > > 
> > > Are you sure these are in the correct order?
> > > 
> > > What is the history of this commit?
> > > 
> > > > ---
> > > >  .../devicetree/bindings/input/st-keypad.txt        |  50 ++++
> > > 
> > > This should be submitted as a seperate patch.
> > 
> > Why do we have such requirement? To me it would make more sense to add
> > binding documentation in the same commit as the code that uses these
> > bindings.
> 
> I'm inclined to agree with you and that's actually how we used to do
> it, but a decision was made by the DT guys at one of the Kernel
> Summits to submit Documentation as a separate patch.

Do you have background for this decision? To me it is akin splitting
header file into a separate patch.
Lee Jones March 10, 2014, 4:35 p.m. UTC | #6
> > > > > This patch adds ST Keyscan driver to use the keypad hw a subset
> > > > > of ST boards provide. Specific board setup will be put in the
> > > > > given dt.
> > > > > 
> > > > > Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com>
> > > > > Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
> > > > 
> > > > Are you sure these are in the correct order?
> > > > 
> > > > What is the history of this commit?
> > > > 
> > > > > ---
> > > > >  .../devicetree/bindings/input/st-keypad.txt        |  50 ++++
> > > > 
> > > > This should be submitted as a seperate patch.
> > > 
> > > Why do we have such requirement? To me it would make more sense to add
> > > binding documentation in the same commit as the code that uses these
> > > bindings.
> > 
> > I'm inclined to agree with you and that's actually how we used to do
> > it, but a decision was made by the DT guys at one of the Kernel
> > Summits to submit Documentation as a separate patch.
> 
> Do you have background for this decision? To me it is akin splitting
> header file into a separate patch.

The discussion/decision was verbal unfortunately.

I don't really mind either way. I'm just attempting to enforce the
decisions that were made by the forces-that-be. Perhaps ping
devicetree@vger.kernel.org with me in CC for more clarification if
required.
Gabriel Fernandez March 14, 2014, 10:13 a.m. UTC | #7
Hi Lee,

On 03/10/2014 12:48 PM, Lee Jones wrote:
> Hi Gabi,
>
> Sorry for the delay. It was a hectic week last week.
>
> As promised:
>
>> This patch adds ST Keyscan driver to use the keypad hw a subset
>> of ST boards provide. Specific board setup will be put in the
>> given dt.
>>
>> Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com>
>> Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
> Are you sure these are in the correct order?
ok i change the order

>> +- linux,keymap: The keymap for keys as described in the binding document
>> +  devicetree/bindings/input/matrix-keymap.txt.
>> +
>> +- keypad,num-rows: Number of row lines connected to the keypad controller.
>> +
>> +- keypad,num-columns: Number of column lines connected to the keypad
>> +  controller.
>> +
>> +- st,debounce_us: Debouncing interval time in microseconds
> I'm sure there will be a shared binding for de-bounce.
>
> If not, there certainly should be.

you want to refer to "debounce-interval" ?

>
> +Example:
> +
> +keyscan: keyscan@fe4b0000 {
> +	compatible = "st,keypad";
> Is there any way we can make this more specific to _this_ IP?
for my knowledge this IP is the same for stixxxx platform.


>
>> +	  To compile this driver as a module, choose M here: the
>> +	  module will be called stm-keyscan.
>> +
>>   config KEYBOARD_SUNKBD
>>   	tristate "Sun Type 4 and Type 5 keyboard"
>>   	select SERIO
>> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
>> index a699b61..5fd020a 100644
>> --- a/drivers/input/keyboard/Makefile
>> +++ b/drivers/input/keyboard/Makefile
>> @@ -50,6 +50,7 @@ obj-$(CONFIG_KEYBOARD_SH_KEYSC)		+= sh_keysc.o
>>   obj-$(CONFIG_KEYBOARD_SPEAR)		+= spear-keyboard.o
>>   obj-$(CONFIG_KEYBOARD_STMPE)		+= stmpe-keypad.o
>>   obj-$(CONFIG_KEYBOARD_STOWAWAY)		+= stowaway.o
>> +obj-$(CONFIG_KEYBOARD_ST_KEYSCAN)	+= st-keyscan.o
>>   obj-$(CONFIG_KEYBOARD_SUNKBD)		+= sunkbd.o
>>   obj-$(CONFIG_KEYBOARD_TC3589X)		+= tc3589x-keypad.o
>>   obj-$(CONFIG_KEYBOARD_TEGRA)		+= tegra-kbc.o
>> diff --git a/drivers/input/keyboard/st-keyscan.c b/drivers/input/keyboard/st-keyscan.c
>> new file mode 100644
>> index 0000000..606cc19
>> --- /dev/null
>> +++ b/drivers/input/keyboard/st-keyscan.c
>> @@ -0,0 +1,323 @@
>> +/*
>> + * STMicroelectronics Key Scanning driver
>> + *
>> + * Copyright (c) 2014 STMicroelectonics Ltd.
>> + * Author: Stuart Menefy <stuart.menefy@st.com>
>> + *
>> + * Based on sh_keysc.c, copyright 2008 Magnus Damm
> Did sh_keysc.c ever exist in Mainline?
i think no, i 'll suppress "Based on sh_keysc.c, copyright 2008 Magnus Damm"

>
>> + * 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/interrupt.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/clk.h>
>> +#include <linux/io.h>
>> +#include <linux/input/matrix_keypad.h>
>> +
>> +#define ST_KEYSCAN_MAXKEYS 16
>> +
>> +#define KEYSCAN_CONFIG_OFF		0x000
>> +#define KEYSCAN_CONFIG_ENABLE		1
> 0x001?
>
>> +#define KEYSCAN_DEBOUNCE_TIME_OFF	0x004
>> +#define KEYSCAN_MATRIX_STATE_OFF	0x008
>> +#define KEYSCAN_MATRIX_DIM_OFF		0x00c
> Odd that these are 3 digit padded? Is there a reason for that?
no reason for the padded,  i will change that.

>> +struct keypad_platform_data {
>> +	const struct matrix_keymap_data *keymap_data;
>> +	unsigned int num_out_pads;
>> +	unsigned int num_in_pads;
>> +	unsigned int debounce_us;
>> +};
>> +
>> +struct keyscan_priv {
>> +	void __iomem *base;
>> +	int irq;
>> +	struct clk *clk;
>> +	struct input_dev *input_dev;
>> +	struct keypad_platform_data *config;
>> +	unsigned int last_state;
>> +	u32 keycodes[ST_KEYSCAN_MAXKEYS];
> Seems odd to limit this. Can't the information come from DT
> i.e. keypad,num-rows and keypad,num-columns?
>
i 'll rename 'num_out_pads' into 'n_rows' and 'num_in_pads' into 'n_cols'



> Nit: It's pretty unusual to use this for a standard error handling
> variable. Consider 'ret' or 'err' as a replacement.
>
>> +	}
>> +
>> +	of_property_read_u32(np, "st,debounce_us", &pdata->debounce_us);
> Isn't this a required property? Might be worth checking the return
> value if so.
no mandatory property, i will update the  dt binding.

>
>> +	st_kp->config = pdata;
>> +
>> +	dev_info(dev, "rows=%d col=%d debounce=%d\n",
>> +			pdata->num_out_pads,
>> +			pdata->num_in_pads,
>> +			pdata->debounce_us);
> Might be worth moving this down passed the final point of failure.
>
>> +	error = of_property_read_u32_array(np, "linux,keymap",
>> +					st_kp->keycodes, ST_KEYSCAN_MAXKEYS);
>> +	if (error) {
>> +		dev_err(dev, "failed to parse keymap\n");
>> +		return error;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int __init keyscan_probe(struct platform_device *pdev)
>> +{
>> +	struct keypad_platform_data *pdata =
>> +		dev_get_platdata(&pdev->dev);
> Do we really support platform data still?
no, i will remove that.

> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(dev, "no I/O memory specified\n");
> +		return -ENXIO;
> +	}
> +
> +	len = resource_size(res);
> +	if (!devm_request_mem_region(dev, res->start, len, pdev->name)) {
> +		dev_err(dev, "failed to reserve I/O memory\n");
> +		return -EBUSY;
> +	}
> +
> +	st_kp->base = devm_ioremap_nocache(dev, res->start, len);
> +	if (st_kp->base == NULL) {
> +		dev_err(dev, "failed to remap I/O memory\n");
> +		return -ENXIO;
> +	}
> Replace the two above with devm_ioremap_resource().
>
> Make sure the IORESOURCE_CACHEABLE is set.
ok, we are in no cacheable use case.

>
>> +	}
>> +
>> +	error = devm_request_irq(dev, st_kp->irq, keyscan_isr, 0,
>> +				 pdev->name, pdev);
>> +	if (error) {
>> +		dev_err(dev, "failed to request IRQ\n");
>> +		return error;
>> +	}
>> +
>> +	input_dev = devm_input_allocate_device(&pdev->dev);
>> +	if (!input_dev) {
>> +		dev_err(&pdev->dev, "failed to allocate the input device\n");
>> +		return -ENOMEM;
>> +	}
>> +
>> +	st_kp->clk = devm_clk_get(dev, NULL);
>> +	if (IS_ERR(st_kp->clk)) {
>> +		dev_err(dev, "cannot get clock");
>> +		return PTR_ERR(st_kp->clk);
>> +	}
>> +
>> +	input_dev = input_allocate_device();
>> +	if (!input_dev) {
>> +		dev_err(dev, "failed to allocate input device\n");
>> +		return -ENOMEM;
>> +	}
> Wasn't this done already?
yes, crap these lines.
>> +	st_kp->input_dev = input_dev;
>> +
>> +	input_dev->name = pdev->name;
>> +	input_dev->phys = "keyscan-keys/input0";
>> +	input_dev->dev.parent = dev;
>> +
>> +	input_dev->id.bustype = BUS_HOST;
>> +	input_dev->id.vendor = 0x0001;
>> +	input_dev->id.product = 0x0001;
>> +	input_dev->id.version = 0x0100;
> Any chance we can #define these?
i will follow Dmitry remark (omit these information)

>
>> +	if (!pdata) {
>> +		error = keypad_matrix_key_parse_dt(st_kp);
>> +		if (error)
>> +			return error;
>> +		pdata = st_kp->config;
> Is pdata used after this?
no, i will remove platform data support


Thanks

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Lee Jones March 14, 2014, 10:42 a.m. UTC | #8
> >Sorry for the delay. It was a hectic week last week.
> >
> >As promised:
> >
> >>This patch adds ST Keyscan driver to use the keypad hw a subset
> >>of ST boards provide. Specific board setup will be put in the
> >>given dt.
> >>
> >>Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com>
> >>Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
> >Are you sure these are in the correct order?
> ok i change the order

I'm not saying they are in the wrong order, I'm just asking. Who wrote
the patch? Has it changed since?

> >>+- linux,keymap: The keymap for keys as described in the binding document
> >>+  devicetree/bindings/input/matrix-keymap.txt.
> >>+
> >>+- keypad,num-rows: Number of row lines connected to the keypad controller.
> >>+
> >>+- keypad,num-columns: Number of column lines connected to the keypad
> >>+  controller.
> >>+
> >>+- st,debounce_us: Debouncing interval time in microseconds
> >I'm sure there will be a shared binding for de-bounce.
> >
> >If not, there certainly should be.
> 
> you want to refer to "debounce-interval" ?

That sounds more generic, but if it's not documented as such, then
please consider doing so.

> >+Example:
> >+
> >+keyscan: keyscan@fe4b0000 {
> >+	compatible = "st,keypad";
> >Is there any way we can make this more specific to _this_ IP?
> for my knowledge this IP is the same for stixxxx platform.

So st,stix-keypad, or st,sti4x-keypad?

I'm just thinking about future proofing the architecture. What if ST
released stj which has a different keypad IP?

> >>+struct keyscan_priv {
> >>+	void __iomem *base;
> >>+	int irq;
> >>+	struct clk *clk;
> >>+	struct input_dev *input_dev;
> >>+	struct keypad_platform_data *config;
> >>+	unsigned int last_state;
> >>+	u32 keycodes[ST_KEYSCAN_MAXKEYS];
> >Seems odd to limit this. Can't the information come from DT
> >i.e. keypad,num-rows and keypad,num-columns?
> >
> i 'll rename 'num_out_pads' into 'n_rows' and 'num_in_pads' into
> 'n_cols'

That's not quite what I meant, I mean can't ST_KEY_MAXKEYS be more
dynamic and be obtained from (keypad,num-rows * keypad,num-columns)?
Dmitry Torokhov March 14, 2014, 3:26 p.m. UTC | #9
On Fri, Mar 14, 2014 at 11:13:17AM +0100, Gabriel Fernandez wrote:
> Hi Lee,
> 
> On 03/10/2014 12:48 PM, Lee Jones wrote:
> >Hi Gabi,
> >
> >Sorry for the delay. It was a hectic week last week.
> >
> >As promised:
> >
> >>This patch adds ST Keyscan driver to use the keypad hw a subset
> >>of ST boards provide. Specific board setup will be put in the
> >>given dt.
> >>
> >>Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com>
> >>Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
> >Are you sure these are in the correct order?
> ok i change the order
> 
> >>+- linux,keymap: The keymap for keys as described in the binding document
> >>+  devicetree/bindings/input/matrix-keymap.txt.
> >>+
> >>+- keypad,num-rows: Number of row lines connected to the keypad controller.
> >>+
> >>+- keypad,num-columns: Number of column lines connected to the keypad
> >>+  controller.
> >>+
> >>+- st,debounce_us: Debouncing interval time in microseconds
> >I'm sure there will be a shared binding for de-bounce.
> >
> >If not, there certainly should be.
> 
> you want to refer to "debounce-interval" ?
> 
> >
> >+Example:
> >+
> >+keyscan: keyscan@fe4b0000 {
> >+	compatible = "st,keypad";
> >Is there any way we can make this more specific to _this_ IP?
> for my knowledge this IP is the same for stixxxx platform.
> 
> 
> >
> >>+	  To compile this driver as a module, choose M here: the
> >>+	  module will be called stm-keyscan.
> >>+
> >>  config KEYBOARD_SUNKBD
> >>  	tristate "Sun Type 4 and Type 5 keyboard"
> >>  	select SERIO
> >>diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> >>index a699b61..5fd020a 100644
> >>--- a/drivers/input/keyboard/Makefile
> >>+++ b/drivers/input/keyboard/Makefile
> >>@@ -50,6 +50,7 @@ obj-$(CONFIG_KEYBOARD_SH_KEYSC)		+= sh_keysc.o
> >>  obj-$(CONFIG_KEYBOARD_SPEAR)		+= spear-keyboard.o
> >>  obj-$(CONFIG_KEYBOARD_STMPE)		+= stmpe-keypad.o
> >>  obj-$(CONFIG_KEYBOARD_STOWAWAY)		+= stowaway.o
> >>+obj-$(CONFIG_KEYBOARD_ST_KEYSCAN)	+= st-keyscan.o
> >>  obj-$(CONFIG_KEYBOARD_SUNKBD)		+= sunkbd.o
> >>  obj-$(CONFIG_KEYBOARD_TC3589X)		+= tc3589x-keypad.o
> >>  obj-$(CONFIG_KEYBOARD_TEGRA)		+= tegra-kbc.o
> >>diff --git a/drivers/input/keyboard/st-keyscan.c b/drivers/input/keyboard/st-keyscan.c
> >>new file mode 100644
> >>index 0000000..606cc19
> >>--- /dev/null
> >>+++ b/drivers/input/keyboard/st-keyscan.c
> >>@@ -0,0 +1,323 @@
> >>+/*
> >>+ * STMicroelectronics Key Scanning driver
> >>+ *
> >>+ * Copyright (c) 2014 STMicroelectonics Ltd.
> >>+ * Author: Stuart Menefy <stuart.menefy@st.com>
> >>+ *
> >>+ * Based on sh_keysc.c, copyright 2008 Magnus Damm
> >Did sh_keysc.c ever exist in Mainline?
> i think no, i 'll suppress "Based on sh_keysc.c, copyright 2008 Magnus Damm"

It is still in here:

[dtor@dtor-d630 work]$ git log --oneline --
drivers/input/keyboard/sh_keysc.c | wc -l
31
[dtor@dtor-d630 work]$
Gabriel Fernandez March 18, 2014, 10:25 a.m. UTC | #10
Hi Lee,

On 03/14/2014 11:42 AM, Lee Jones wrote:
>>> Sorry for the delay. It was a hectic week last week.
>>>
>>> As promised:
>>>
>>>> This patch adds ST Keyscan driver to use the keypad hw a subset
>>>> of ST boards provide. Specific board setup will be put in the
>>>> given dt.
>>>>
>>>> Signed-off-by: Giuseppe Condorelli<giuseppe.condorelli@st.com>
>>>> Signed-off-by: Gabriel Fernandez<gabriel.fernandez@st.com>
>>> Are you sure these are in the correct order?
>> ok i change the order
> I'm not saying they are in the wrong order, I'm just asking. Who wrote
> the patch? Has it changed since?
Sorry...
I wrote the patch, then Guiseppe has changed and tested, and I re-modifiedit
>>>> +- linux,keymap: The keymap for keys as described in the binding document
>>>> +  devicetree/bindings/input/matrix-keymap.txt.
>>>> +
>>>> +- keypad,num-rows: Number of row lines connected to the keypad controller.
>>>> +
>>>> +- keypad,num-columns: Number of column lines connected to the keypad
>>>> +  controller.
>>>> +
>>>> +- st,debounce_us: Debouncing interval time in microseconds
>>> I'm sure there will be a shared binding for de-bounce.
>>>
>>> If not, there certainly should be.
>> you want to refer to "debounce-interval" ?
> That sounds more generic, but if it's not documented as such, then
> please consider doing so.
>
>>> +Example:
>>> +
>>> +keyscan: keyscan@fe4b0000 {
>>> +	compatible = "st,keypad";
>>> Is there any way we can make this more specific to _this_ IP?
>> for my knowledge this IP is the same for stixxxx platform.
> So st,stix-keypad, or st,sti4x-keypad?
>
> I'm just thinking about future proofing the architecture. What if ST
> released stj which has a different keypad IP?
After discussing internally with st  "st,sti-keyscan" is better

>>>> +struct keyscan_priv {
>>>> +	void __iomem *base;
>>>> +	int irq;
>>>> +	struct clk *clk;
>>>> +	struct input_dev *input_dev;
>>>> +	struct keypad_platform_data *config;
>>>> +	unsigned int last_state;
>>>> +	u32 keycodes[ST_KEYSCAN_MAXKEYS];
>>> Seems odd to limit this. Can't the information come from DT
>>> i.e. keypad,num-rows and keypad,num-columns?
>>>
>> i 'll rename 'num_out_pads' into 'n_rows' and 'num_in_pads' into
>> 'n_cols'
> That's not quite what I meant, I mean can't ST_KEY_MAXKEYS be more
> dynamic and be obtained from (keypad,num-rows * keypad,num-columns)?
ok


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Lee Jones March 18, 2014, 11:01 a.m. UTC | #11
> >>>Sorry for the delay. It was a hectic week last week.
> >>>
> >>>As promised:
> >>>
> >>>>This patch adds ST Keyscan driver to use the keypad hw a subset
> >>>>of ST boards provide. Specific board setup will be put in the
> >>>>given dt.
> >>>>
> >>>>Signed-off-by: Giuseppe Condorelli<giuseppe.condorelli@st.com>
> >>>>Signed-off-by: Gabriel Fernandez<gabriel.fernandez@st.com>
> >>>Are you sure these are in the correct order?
> >>ok i change the order
> >I'm not saying they are in the wrong order, I'm just asking. Who wrote
> >the patch? Has it changed since?
> Sorry...
> I wrote the patch, then Guiseppe has changed and tested, and I re-modifiedit

Ah, then it starts to get very complicated. :)

If you wrote the patch, you need to be at the top of the list.

<snip>

> >>>+keyscan: keyscan@fe4b0000 {
> >>>+	compatible = "st,keypad";
> >>>Is there any way we can make this more specific to _this_ IP?
> >>for my knowledge this IP is the same for stixxxx platform.
> >So st,stix-keypad, or st,sti4x-keypad?
> >
> >I'm just thinking about future proofing the architecture. What if ST
> >released stj which has a different keypad IP?
> After discussing internally with st  "st,sti-keyscan" is better

Perfect.

<snip>
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/input/st-keypad.txt b/Documentation/devicetree/bindings/input/st-keypad.txt
new file mode 100644
index 0000000..63eb07a
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/st-keypad.txt
@@ -0,0 +1,50 @@ 
+* ST Keypad controller device tree bindings
+
+The ST keypad controller device tree binding is based on the
+matrix-keymap.
+
+Required properties:
+
+- compatible: "st,keypad"
+
+- reg: Register base address of st-keypad controler.
+
+- interrupts: Interrupt numberof st-keypad controler.
+
+- clocks: Must contain one entry, for the module clock.
+  See ../clocks/clock-bindings.txt for details.
+
+- pinctrl-0: Should specify pin control groups used for this controller.
+
+- pinctrl-names: Should contain only one value - "default".
+
+- linux,keymap: The keymap for keys as described in the binding document
+  devicetree/bindings/input/matrix-keymap.txt.
+
+- keypad,num-rows: Number of row lines connected to the keypad controller.
+
+- keypad,num-columns: Number of column lines connected to the keypad
+  controller.
+
+- st,debounce_us: Debouncing interval time in microseconds
+
+
+Example:
+
+keyscan: keyscan@fe4b0000 {
+	compatible = "st,keypad";
+	reg = <0xfe4b0000 0x2000>;
+	interrupts = <GIC_SPI 212 IRQ_TYPE_NONE>;
+	clocks	= <&CLK_SYSIN>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_keyscan>;
+
+	keypad,num-rows = <4>;
+	keypad,num-columns = <4>;
+	st,debounce_us = <5000>;
+	linux,keymap = < /* in0	in1	in2	in3 */
+		KEY_F13 KEY_F9  KEY_F5 KEY_F1		/* out0 */
+		KEY_F14 KEY_F10 KEY_F6 KEY_F2		/* out1 */
+		KEY_F15 KEY_F11 KEY_F7 KEY_F3		/* out2 */
+		KEY_F16 KEY_F12 KEY_F8 KEY_F4 >;	/* out3 */
+};
diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index a673c9f..9e29125 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -512,6 +512,18 @@  config KEYBOARD_STOWAWAY
 	  To compile this driver as a module, choose M here: the
 	  module will be called stowaway.
 
+config KEYBOARD_ST_KEYSCAN
+	tristate "STMicroelectronics keyscan support"
+	depends on ARCH_STI
+	select INPUT_EVDEV
+	select INPUT_MATRIXKMAP
+	help
+	  Say Y here if you want to use a keypad attached to the keyscan block
+	  on some STMicroelectronics SoC devices.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called stm-keyscan.
+
 config KEYBOARD_SUNKBD
 	tristate "Sun Type 4 and Type 5 keyboard"
 	select SERIO
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index a699b61..5fd020a 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -50,6 +50,7 @@  obj-$(CONFIG_KEYBOARD_SH_KEYSC)		+= sh_keysc.o
 obj-$(CONFIG_KEYBOARD_SPEAR)		+= spear-keyboard.o
 obj-$(CONFIG_KEYBOARD_STMPE)		+= stmpe-keypad.o
 obj-$(CONFIG_KEYBOARD_STOWAWAY)		+= stowaway.o
+obj-$(CONFIG_KEYBOARD_ST_KEYSCAN)	+= st-keyscan.o
 obj-$(CONFIG_KEYBOARD_SUNKBD)		+= sunkbd.o
 obj-$(CONFIG_KEYBOARD_TC3589X)		+= tc3589x-keypad.o
 obj-$(CONFIG_KEYBOARD_TEGRA)		+= tegra-kbc.o
diff --git a/drivers/input/keyboard/st-keyscan.c b/drivers/input/keyboard/st-keyscan.c
new file mode 100644
index 0000000..606cc19
--- /dev/null
+++ b/drivers/input/keyboard/st-keyscan.c
@@ -0,0 +1,323 @@ 
+/*
+ * STMicroelectronics Key Scanning driver
+ *
+ * Copyright (c) 2014 STMicroelectonics Ltd.
+ * Author: Stuart Menefy <stuart.menefy@st.com>
+ *
+ * Based on sh_keysc.c, copyright 2008 Magnus Damm
+ *
+ * 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/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/input/matrix_keypad.h>
+
+#define ST_KEYSCAN_MAXKEYS 16
+
+#define KEYSCAN_CONFIG_OFF		0x000
+#define KEYSCAN_CONFIG_ENABLE		1
+#define KEYSCAN_DEBOUNCE_TIME_OFF	0x004
+#define KEYSCAN_MATRIX_STATE_OFF	0x008
+#define KEYSCAN_MATRIX_DIM_OFF		0x00c
+#define KEYSCAN_MATRIX_DIM_X_SHIFT	0
+#define KEYSCAN_MATRIX_DIM_Y_SHIFT	2
+
+struct keypad_platform_data {
+	const struct matrix_keymap_data *keymap_data;
+	unsigned int num_out_pads;
+	unsigned int num_in_pads;
+	unsigned int debounce_us;
+};
+
+struct keyscan_priv {
+	void __iomem *base;
+	int irq;
+	struct clk *clk;
+	struct input_dev *input_dev;
+	struct keypad_platform_data *config;
+	unsigned int last_state;
+	u32 keycodes[ST_KEYSCAN_MAXKEYS];
+};
+
+static irqreturn_t keyscan_isr(int irq, void *dev_id)
+{
+	struct platform_device *pdev = dev_id;
+	struct keyscan_priv *priv = platform_get_drvdata(pdev);
+	int state;
+	int change;
+
+	state = readl(priv->base + KEYSCAN_MATRIX_STATE_OFF) & 0xffff;
+	change = priv->last_state ^ state;
+
+	while (change) {
+		int scancode = __ffs(change);
+		int down = state & (1 << scancode);
+
+		input_report_key(priv->input_dev, priv->keycodes[scancode],
+				 down);
+		change ^= 1 << scancode;
+	};
+
+	input_sync(priv->input_dev);
+
+	priv->last_state = state;
+
+	return IRQ_HANDLED;
+}
+
+static void keyscan_start(struct keyscan_priv *priv)
+{
+	clk_enable(priv->clk);
+
+	writel(priv->config->debounce_us * (clk_get_rate(priv->clk) / 1000000),
+	       priv->base + KEYSCAN_DEBOUNCE_TIME_OFF);
+
+	writel(((priv->config->num_in_pads - 1) << KEYSCAN_MATRIX_DIM_X_SHIFT) |
+	       ((priv->config->num_out_pads - 1) << KEYSCAN_MATRIX_DIM_Y_SHIFT),
+	       priv->base + KEYSCAN_MATRIX_DIM_OFF);
+
+	writel(KEYSCAN_CONFIG_ENABLE, priv->base + KEYSCAN_CONFIG_OFF);
+}
+
+static void keyscan_stop(struct keyscan_priv *priv)
+{
+	writel(0, priv->base + KEYSCAN_CONFIG_OFF);
+
+	clk_disable(priv->clk);
+}
+
+static int keypad_matrix_key_parse_dt(struct keyscan_priv *st_kp)
+{
+	struct device *dev = st_kp->input_dev->dev.parent;
+	struct device_node *np = dev->of_node;
+	struct keypad_platform_data *pdata;
+	int error;
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata) {
+		dev_err(dev, "failed to allocate driver pdata\n");
+		return -ENOMEM;
+	}
+
+	error = matrix_keypad_parse_of_params(dev, &pdata->num_out_pads,
+			&pdata->num_in_pads);
+	if (error) {
+		dev_err(dev, "failed to parse keypad params\n");
+		return error;
+	}
+
+	of_property_read_u32(np, "st,debounce_us", &pdata->debounce_us);
+
+	st_kp->config = pdata;
+
+	dev_info(dev, "rows=%d col=%d debounce=%d\n",
+			pdata->num_out_pads,
+			pdata->num_in_pads,
+			pdata->debounce_us);
+
+	error = of_property_read_u32_array(np, "linux,keymap",
+					st_kp->keycodes, ST_KEYSCAN_MAXKEYS);
+	if (error) {
+		dev_err(dev, "failed to parse keymap\n");
+		return error;
+	}
+
+	return 0;
+}
+
+static int __init keyscan_probe(struct platform_device *pdev)
+{
+	struct keypad_platform_data *pdata =
+		dev_get_platdata(&pdev->dev);
+	struct keyscan_priv *st_kp;
+	struct input_dev *input_dev;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	int len;
+	int error;
+	int i;
+
+	if (!pdata && !pdev->dev.of_node) {
+		dev_err(&pdev->dev, "no keymap defined\n");
+		return -EINVAL;
+	}
+
+	st_kp = devm_kzalloc(dev, sizeof(*st_kp), GFP_KERNEL);
+	if (!st_kp) {
+		dev_err(dev, "failed to allocate driver data\n");
+		return -ENOMEM;
+	}
+	st_kp->config = pdata;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(dev, "no I/O memory specified\n");
+		return -ENXIO;
+	}
+
+	len = resource_size(res);
+	if (!devm_request_mem_region(dev, res->start, len, pdev->name)) {
+		dev_err(dev, "failed to reserve I/O memory\n");
+		return -EBUSY;
+	}
+
+	st_kp->base = devm_ioremap_nocache(dev, res->start, len);
+	if (st_kp->base == NULL) {
+		dev_err(dev, "failed to remap I/O memory\n");
+		return -ENXIO;
+	}
+
+	st_kp->irq = platform_get_irq(pdev, 0);
+	if (st_kp->irq < 0) {
+		dev_err(dev, "no IRQ specified\n");
+		return -ENXIO;
+	}
+
+	error = devm_request_irq(dev, st_kp->irq, keyscan_isr, 0,
+				 pdev->name, pdev);
+	if (error) {
+		dev_err(dev, "failed to request IRQ\n");
+		return error;
+	}
+
+	input_dev = devm_input_allocate_device(&pdev->dev);
+	if (!input_dev) {
+		dev_err(&pdev->dev, "failed to allocate the input device\n");
+		return -ENOMEM;
+	}
+
+	st_kp->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(st_kp->clk)) {
+		dev_err(dev, "cannot get clock");
+		return PTR_ERR(st_kp->clk);
+	}
+
+	input_dev = input_allocate_device();
+	if (!input_dev) {
+		dev_err(dev, "failed to allocate input device\n");
+		return -ENOMEM;
+	}
+	st_kp->input_dev = input_dev;
+
+	input_dev->name = pdev->name;
+	input_dev->phys = "keyscan-keys/input0";
+	input_dev->dev.parent = dev;
+
+	input_dev->id.bustype = BUS_HOST;
+	input_dev->id.vendor = 0x0001;
+	input_dev->id.product = 0x0001;
+	input_dev->id.version = 0x0100;
+
+	if (!pdata) {
+		error = keypad_matrix_key_parse_dt(st_kp);
+		if (error)
+			return error;
+		pdata = st_kp->config;
+	}
+
+	input_dev->keycode = st_kp->keycodes;
+	input_dev->keycodesize = sizeof(st_kp->keycodes[0]);
+	input_dev->keycodemax = ARRAY_SIZE(st_kp->keycodes);
+
+	for (i = 0; i < ST_KEYSCAN_MAXKEYS; i++)
+		input_set_capability(input_dev, EV_KEY, st_kp->keycodes[i]);
+	__clear_bit(KEY_RESERVED, input_dev->keybit);
+
+	error = input_register_device(input_dev);
+	if (error) {
+		dev_err(dev, "failed to register input device\n");
+		input_free_device(input_dev);
+		platform_set_drvdata(pdev, NULL);
+		return error;
+	}
+
+	platform_set_drvdata(pdev, st_kp);
+
+	keyscan_start(st_kp);
+
+	device_set_wakeup_capable(&pdev->dev, 1);
+
+	return 0;
+}
+
+static int __exit keyscan_remove(struct platform_device *pdev)
+{
+	struct keyscan_priv *priv = platform_get_drvdata(pdev);
+
+	keyscan_stop(priv);
+
+	input_unregister_device(priv->input_dev);
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+static int keyscan_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct keyscan_priv *priv = platform_get_drvdata(pdev);
+
+	if (device_may_wakeup(dev))
+		enable_irq_wake(priv->irq);
+	else
+		keyscan_stop(priv);
+
+	return 0;
+}
+
+static int keyscan_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct keyscan_priv *priv = platform_get_drvdata(pdev);
+
+	if (device_may_wakeup(dev))
+		disable_irq_wake(priv->irq);
+	else
+		keyscan_start(priv);
+
+	return 0;
+}
+
+static const struct dev_pm_ops keyscan_dev_pm_ops = {
+	.suspend = keyscan_suspend,
+	.resume = keyscan_resume,
+};
+
+static const struct of_device_id keyscan_of_match[] = {
+	{ .compatible = "st,keypad" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, keyscan_of_match);
+
+__refdata struct platform_driver keyscan_device_driver = {
+	.probe		= keyscan_probe,
+	.remove		= __exit_p(keyscan_remove),
+	.driver		= {
+		.name	= "st-keyscan",
+		.pm	= &keyscan_dev_pm_ops,
+		.of_match_table = of_match_ptr(keyscan_of_match),
+	}
+};
+
+static int __init keyscan_init(void)
+{
+	return platform_driver_register(&keyscan_device_driver);
+}
+
+static void __exit keyscan_exit(void)
+{
+	platform_driver_unregister(&keyscan_device_driver);
+}
+
+module_init(keyscan_init);
+module_exit(keyscan_exit);
+
+MODULE_AUTHOR("Stuart Menefy <stuart.menefy@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics keyscan device driver");
+MODULE_LICENSE("GPL");