Re: [PATCH v2 1/2] Input: add regulator haptic driver

[Chanwoo Choi <cw00.choi@samsung.com>]

On 11/24/2014 11:50 PM, Jaewon Kim wrote:
> This patch adds support for haptic driver controlled by
> voltage of regulator. And this driver support for
> Force Feedback interface from input framework
> 
> Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
> Signed-off-by: Hyunhee Kim <hyunhee.kim@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>

Looks good to me.

I tested this patch on Exynos3250-based Rinato (Samsung Gear2) board.

Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>

Thanks,
Chanwoo Choi

> ---
>  .../devicetree/bindings/input/regulator-haptic.txt |   24 ++
>  drivers/input/misc/Kconfig                         |   11 +
>  drivers/input/misc/Makefile                        |    1 +
>  drivers/input/misc/regulator-haptic.c              |  247 ++++++++++++++++++++
>  include/linux/input/regulator-haptic.h             |   30 +++
>  5 files changed, 313 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/input/regulator-haptic.txt
>  create mode 100644 drivers/input/misc/regulator-haptic.c
>  create mode 100644 include/linux/input/regulator-haptic.h
> 
> diff --git a/Documentation/devicetree/bindings/input/regulator-haptic.txt b/Documentation/devicetree/bindings/input/regulator-haptic.txt
> new file mode 100644
> index 0000000..5a44e8f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/regulator-haptic.txt
> @@ -0,0 +1,24 @@
> +* Requlator Haptic Device Tree Bindings
> +
> +The regulator haptic driver controlled by voltage of regulator.
> +This driver implemented via Force Feedback interface.
> +
> +Required Properties:
> + - compatible : Should be "regulator-haptic"
> + - haptic-supply : Power supply to the haptic motor.
> +	[*] refer Documentation/devicetree/bindings/regulator/regulator.txt
> +
> + - max-microvolt : The maximum voltage value supplied to the haptic motor.
> +		[The unit of the voltage is a micro]
> +
> + - min-microvolt : The minimum voltage value supplied to the haptic motor.
> +		[The unit of the voltage is a micro]
> +
> +Example:
> +
> +	haptics {
> +		compatible = "regulator-haptic";
> +		haptic-supply = <&motor_regulator>;
> +		max-microvolt = <2700000>;
> +		min-microvolt = <1100000>;
> +	};
> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
> index 23297ab..e5e556d 100644
> --- a/drivers/input/misc/Kconfig
> +++ b/drivers/input/misc/Kconfig
> @@ -394,6 +394,17 @@ config INPUT_CM109
>  	  To compile this driver as a module, choose M here: the module will be
>  	  called cm109.
>  
> +config INPUT_REGULATOR_HAPTIC
> +	tristate "regulator haptics support"
> +	select INPUT_FF_MEMLESS
> +	help
> +	  This option enables device driver support for the haptic controlled
> +	  by regulator. This driver supports ff-memless interface
> +	  from input framework.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called regulator-haptic.
> +
>  config INPUT_RETU_PWRBUTTON
>  	tristate "Retu Power button Driver"
>  	depends on MFD_RETU
> diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
> index 19c7603..1f135af 100644
> --- a/drivers/input/misc/Makefile
> +++ b/drivers/input/misc/Makefile
> @@ -53,6 +53,7 @@ obj-$(CONFIG_INPUT_PMIC8XXX_PWRKEY)	+= pmic8xxx-pwrkey.o
>  obj-$(CONFIG_INPUT_POWERMATE)		+= powermate.o
>  obj-$(CONFIG_INPUT_PWM_BEEPER)		+= pwm-beeper.o
>  obj-$(CONFIG_INPUT_RB532_BUTTON)	+= rb532_button.o
> +obj-$(CONFIG_INPUT_REGULATOR_HAPTIC)	+= regulator-haptic.o
>  obj-$(CONFIG_INPUT_RETU_PWRBUTTON)	+= retu-pwrbutton.o
>  obj-$(CONFIG_INPUT_GPIO_ROTARY_ENCODER)	+= rotary_encoder.o
>  obj-$(CONFIG_INPUT_SGI_BTNS)		+= sgi_btns.o
> diff --git a/drivers/input/misc/regulator-haptic.c b/drivers/input/misc/regulator-haptic.c
> new file mode 100644
> index 0000000..c61dd99
> --- /dev/null
> +++ b/drivers/input/misc/regulator-haptic.c
> @@ -0,0 +1,247 @@
> +/*
> + * Regulator haptic driver
> + *
> + * Copyright (c) 2014 Samsung Electronics Co., Ltd.
> + * Author: Jaewon Kim <jaewon02.kim@samsung.com>
> + * Author: Hyunhee Kim <hyunhee.kim@samsung.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/input.h>
> +#include <linux/input/regulator-haptic.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/slab.h>
> +
> +#define MAX_MAGNITUDE_SHIFT	16
> +
> +struct regulator_haptic {
> +	struct device *dev;
> +	struct input_dev *input_dev;
> +	struct regulator *regulator;
> +	struct work_struct work;
> +
> +	bool enabled;
> +	bool suspend_state;
> +	unsigned int max_volt;
> +	unsigned int min_volt;
> +	unsigned int intensity;
> +	unsigned int magnitude;
> +};
> +
> +static void regulator_haptic_enable(struct regulator_haptic *haptic, bool state)
> +{
> +	int error;
> +
> +	if (haptic->enabled == state)
> +		return;
> +
> +	if (state)
> +		error = regulator_enable(haptic->regulator);
> +	else
> +		error = regulator_disable(haptic->regulator);
> +	if (error) {
> +		dev_err(haptic->dev, "cannot enable regulator\n");
> +		return;
> +	}
> +
> +	haptic->enabled = state;
> +}
> +
> +static void regulator_haptic_work(struct work_struct *work)
> +{
> +	struct regulator_haptic *haptic = container_of(work,
> +					struct regulator_haptic, work);
> +	int error;
> +
> +	error = regulator_set_voltage(haptic->regulator,
> +			haptic->intensity + haptic->min_volt, haptic->max_volt);
> +	if (error) {
> +		dev_err(haptic->dev, "cannot set regulator voltage\n");
> +		return;
> +	}
> +
> +	if (haptic->magnitude)
> +		regulator_haptic_enable(haptic, true);
> +	else
> +		regulator_haptic_enable(haptic, false);
> +}
> +
> +static int regulator_haptic_play_effect(struct input_dev *input, void *data,
> +					struct ff_effect *effect)
> +{
> +	struct regulator_haptic *haptic = input_get_drvdata(input);
> +	u64 volt_mag_multi;
> +
> +	haptic->magnitude = effect->u.rumble.strong_magnitude;
> +	if (!haptic->magnitude)
> +		haptic->magnitude = effect->u.rumble.weak_magnitude;
> +
> +
> +	volt_mag_multi = (u64)(haptic->max_volt - haptic->min_volt) *
> +					haptic->magnitude;
> +	haptic->intensity = (unsigned int)(volt_mag_multi >>
> +					MAX_MAGNITUDE_SHIFT);
> +
> +	schedule_work(&haptic->work);
> +
> +	return 0;
> +}
> +
> +static void regulator_haptic_close(struct input_dev *input)
> +{
> +	struct regulator_haptic *haptic = input_get_drvdata(input);
> +
> +	cancel_work_sync(&haptic->work);
> +	regulator_haptic_enable(haptic, false);
> +}
> +
> +#ifdef CONFIG_OF
> +static int regulator_haptic_parse_dt(struct regulator_haptic *haptic)
> +{
> +	struct device_node *node = haptic->dev->of_node;
> +	int error;
> +
> +	error = of_property_read_u32(node, "max-microvolt", &haptic->max_volt);
> +	if (error) {
> +		dev_err(haptic->dev, "cannot parse max-microvolt\n");
> +		return error;
> +	}
> +
> +	error = of_property_read_u32(node, "min-microvolt", &haptic->min_volt);
> +	if (error) {
> +		dev_err(haptic->dev, "cannot parse min-microvolt\n");
> +		return error;
> +	}
> +
> +	return 0;
> +}
> +#else
> +static int regulator_haptic_parse_dt(struct regulator_haptic *haptic)
> +{
> +	return 0;
> +}
> +#endif /* CONFIG_OF */
> +
> +static int regulator_haptic_probe(struct platform_device *pdev)
> +{
> +	struct regulator_haptic *haptic;
> +	struct regulator_haptic_data *data;
> +	struct input_dev *input_dev;
> +	int error;
> +
> +	haptic = devm_kzalloc(&pdev->dev, sizeof(*haptic), GFP_KERNEL);
> +	if (!haptic)
> +		return -ENOMEM;
> +
> +	haptic->dev = &pdev->dev;
> +	haptic->enabled = false;
> +	haptic->suspend_state = false;
> +	INIT_WORK(&haptic->work, regulator_haptic_work);
> +
> +	if (pdev->dev.of_node) {
> +		error = regulator_haptic_parse_dt(haptic);
> +		if (error) {
> +			dev_err(&pdev->dev, "failed to parse device tree\n");
> +			return error;
> +		}
> +	} else {
> +		data = dev_get_platdata(&pdev->dev);
> +		if (data) {
> +			dev_err(&pdev->dev, "failed to get platdata\n");
> +			return -EINVAL;
> +		}
> +
> +		haptic->regulator = data->regulator;
> +		haptic->max_volt = data->max_volt;
> +		haptic->min_volt = data->min_volt;
> +	}
> +
> +	haptic->regulator = devm_regulator_get(&pdev->dev, "haptic");
> +	if (IS_ERR(haptic->regulator)) {
> +		dev_err(&pdev->dev, "failed to get regulator\n");
> +		return PTR_ERR(haptic->regulator);
> +	}
> +
> +	input_dev = devm_input_allocate_device(&pdev->dev);
> +	if (!input_dev)
> +		return  -ENOMEM;
> +
> +	haptic->input_dev = input_dev;
> +	haptic->input_dev->name = "regulator-haptic";
> +	haptic->input_dev->dev.parent = &pdev->dev;
> +	haptic->input_dev->close = regulator_haptic_close;
> +	input_set_drvdata(haptic->input_dev, haptic);
> +	input_set_capability(haptic->input_dev, EV_FF, FF_RUMBLE);
> +
> +	error = input_ff_create_memless(input_dev, NULL,
> +			      regulator_haptic_play_effect);
> +	if (error) {
> +		dev_err(&pdev->dev, "failed to create force-feedback\n");
> +		return error;
> +	}
> +
> +	error = input_register_device(haptic->input_dev);
> +	if (error) {
> +		dev_err(&pdev->dev, "failed to register input device\n");
> +		return error;
> +	}
> +
> +	platform_set_drvdata(pdev, haptic);
> +
> +	return 0;
> +}
> +
> +static int __maybe_unused regulator_haptic_suspend(struct device *dev)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct regulator_haptic *haptic = platform_get_drvdata(pdev);
> +
> +	if (haptic->enabled) {
> +		regulator_haptic_enable(haptic, false);
> +		haptic->suspend_state = true;
> +	}
> +
> +	return 0;
> +}
> +
> +static int __maybe_unused regulator_haptic_resume(struct device *dev)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct regulator_haptic *haptic = platform_get_drvdata(pdev);
> +
> +	if (haptic->suspend_state) {
> +		regulator_haptic_enable(haptic, true);
> +		haptic->suspend_state = false;
> +	}
> +
> +	return 0;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(regulator_haptic_pm_ops,
> +		regulator_haptic_suspend, regulator_haptic_resume);
> +
> +static struct of_device_id regulator_haptic_dt_match[] = {
> +	{ .compatible = "regulator-haptic" },
> +	{},
> +};
> +
> +static struct platform_driver regulator_haptic_driver = {
> +	.probe		= regulator_haptic_probe,
> +	.driver		= {
> +		.name		= "regulator-haptic",
> +		.of_match_table = regulator_haptic_dt_match,
> +		.pm		= &regulator_haptic_pm_ops,
> +	},
> +};
> +module_platform_driver(regulator_haptic_driver);
> +
> +MODULE_AUTHOR("Jaewon Kim <jaewon02.kim@samsung.com>");
> +MODULE_AUTHOR("Hyunhee Kim <hyunhee.kim@samsung.com>");
> +MODULE_DESCRIPTION("Regulator haptic driver");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/input/regulator-haptic.h b/include/linux/input/regulator-haptic.h
> new file mode 100644
> index 0000000..15a629c
> --- /dev/null
> +++ b/include/linux/input/regulator-haptic.h
> @@ -0,0 +1,30 @@
> +/*
> + * Regulator Haptic Platform Data
> + *
> + * Copyright (c) 2014 Samsung Electronics Co., Ltd.
> + * Author: Jaewon Kim <jaewon02.kim@samsung.com>
> + * Author: Hyunhee Kim <hyunhee.kim@samsung.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.
> + */
> +
> +#ifndef _REGULATOR_HAPTIC_H
> +
> +/*
> + * struct regulator_haptic_data - Platform device data
> + *
> + * @regulator: Power supply to the haptic motor
> + * @max_volt: maximum voltage value supplied to the haptic motor.
> + * 		<The unit of the voltage is a micro>
> + * @min_volt: minimum voltage value supplied to the haptic motor.
> + * 		<The unit of the voltage is a micro>
> + */
> +struct regulator_haptic_data {
> +	struct regulator *regulator;
> +	unsigned int max_volt;
> +	unsigned int min_volt;
> +};
> +
> +#endif /* _REGULATOR_HAPTIC_H */
>