Input: add Qualcomm PM8941 power key driver

Qualcomm PM8941 PMIC Power Key

PROPERTIES

- compatible:

	Usage: required

	Value type: <string>

	Definition: must be one of:

		    "qcom,pm8941-pwrkey"

- reg:

	Usage: required

	Value type: <prop-encoded-array>

	Definition: base address of registers for block

- interrupts:

	Usage: required

	Value type: <prop-encoded-array>

	Definition: key change interrupt; The format of the specifier is

		    defined by the binding document describing the node's

		    interrupt parent.

- debounce:

	Usage: optional

	Value type: <u32>

	Definition: time in microseconds that key must be pressed or released

		    for state change interrupt to trigger.

- bias-pull-up:

	Usage: optional

	Value type: <empty>

	Definition: presence of this property indicates that the KPDPWR_N pin

		    should be configured for pull up.

EXAMPLE

	pwrkey@800 {

		compatible = "qcom,pm8941-pwrkey";

		reg = <0x800>;

		interrupts = <0x0 0x8 0 IRQ_TYPE_EDGE_BOTH>;

		debounce = <15625>;

		bias-pull-up;

	};

	  To compile this driver as a module, choose M here: the

	  module will be called pcspkr.

config INPUT_PM8941_PWRKEY

	tristate "Qualcomm PM8941 power key support"

	depends on MFD_SPMI_PMIC

	help

	  Say Y here if you want support for the power key usually found

	  on boards using a Qualcomm PM8941 compatible PMIC.

	  If unsure, say Y.

	  To compile this driver as a module, choose M here: the module

	  will be called pm8941-pwrkey.

config INPUT_PM8XXX_VIBRATOR

	tristate "Qualcomm PM8XXX vibrator support"

	depends on MFD_PM8XXX

obj-$(CONFIG_INPUT_PCF50633_PMU)	+= pcf50633-input.o

obj-$(CONFIG_INPUT_PCF8574)		+= pcf8574_keypad.o

obj-$(CONFIG_INPUT_PCSPKR)		+= pcspkr.o

obj-$(CONFIG_INPUT_PM8941_PWRKEY)	+= pm8941-pwrkey.o

obj-$(CONFIG_INPUT_PM8XXX_VIBRATOR)	+= pm8xxx-vibrator.o

obj-$(CONFIG_INPUT_PMIC8XXX_PWRKEY)	+= pmic8xxx-pwrkey.o

obj-$(CONFIG_INPUT_POWERMATE)		+= powermate.o

/*

 * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.

 * Copyright (c) 2014, Sony Mobile Communications Inc.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 and

 * only version 2 as published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 */

#include <linux/delay.h>

#include <linux/errno.h>

#include <linux/input.h>

#include <linux/interrupt.h>

#include <linux/kernel.h>

#include <linux/log2.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/platform_device.h>

#include <linux/reboot.h>

#include <linux/regmap.h>

#define PON_REV2			0x01

#define PON_RT_STS			0x10

#define  PON_KPDPWR_N_SET		BIT(0)

#define PON_PS_HOLD_RST_CTL		0x5a

#define PON_PS_HOLD_RST_CTL2		0x5b

#define  PON_PS_HOLD_ENABLE		BIT(7)

#define  PON_PS_HOLD_TYPE_MASK		0x0f

#define  PON_PS_HOLD_TYPE_SHUTDOWN	4

#define  PON_PS_HOLD_TYPE_HARD_RESET	7

#define PON_PULL_CTL			0x70

#define  PON_KPDPWR_PULL_UP		BIT(1)

#define PON_DBC_CTL			0x71

#define  PON_DBC_DELAY_MASK		0x7

struct pm8941_pwrkey {

	struct device *dev;

	int irq;

	u32 baseaddr;

	struct regmap *regmap;

	struct input_dev *input;

	unsigned int revision;

	struct notifier_block reboot_notifier;

};

static int pm8941_reboot_notify(struct notifier_block *nb,

				unsigned long code, void *unused)

{

	struct pm8941_pwrkey *pwrkey = container_of(nb, struct pm8941_pwrkey,

						    reboot_notifier);

	unsigned int enable_reg;

	unsigned int reset_type;

	int error;

	/* PMICs with revision 0 have the enable bit in same register as ctrl */

	if (pwrkey->revision == 0)

		enable_reg = PON_PS_HOLD_RST_CTL;

	else

		enable_reg = PON_PS_HOLD_RST_CTL2;

	error = regmap_update_bits(pwrkey->regmap,

				   pwrkey->baseaddr + enable_reg,

				   PON_PS_HOLD_ENABLE,

				   0);

	if (error)

		dev_err(pwrkey->dev,

			"unable to clear ps hold reset enable: %d\n",

			error);

	/*

	 * Updates of PON_PS_HOLD_ENABLE requires 3 sleep cycles between

	 * writes.

	 */

	usleep_range(100, 1000);

	switch (code) {

	case SYS_HALT:

	case SYS_POWER_OFF:

		reset_type = PON_PS_HOLD_TYPE_SHUTDOWN;

		break;

	case SYS_RESTART:

	default:

		reset_type = PON_PS_HOLD_TYPE_HARD_RESET;

		break;

	};

	error = regmap_update_bits(pwrkey->regmap,

				   pwrkey->baseaddr + PON_PS_HOLD_RST_CTL,

				   PON_PS_HOLD_TYPE_MASK,

				   reset_type);

	if (error)

		dev_err(pwrkey->dev, "unable to set ps hold reset type: %d\n",

			error);

	error = regmap_update_bits(pwrkey->regmap,

				   pwrkey->baseaddr + enable_reg,

				   PON_PS_HOLD_ENABLE,

				   PON_PS_HOLD_ENABLE);

	if (error)

		dev_err(pwrkey->dev, "unable to re-set enable: %d\n", error);

	return NOTIFY_DONE;

}

static irqreturn_t pm8941_pwrkey_irq(int irq, void *_data)

{

	struct pm8941_pwrkey *pwrkey = _data;

	unsigned int sts;

	int error;

	error = regmap_read(pwrkey->regmap,

			    pwrkey->baseaddr + PON_RT_STS, &sts);

	if (error)

		return IRQ_HANDLED;

	input_report_key(pwrkey->input, KEY_POWER, !!(sts & PON_KPDPWR_N_SET));

	input_sync(pwrkey->input);

	return IRQ_HANDLED;

}

static int __maybe_unused pm8941_pwrkey_suspend(struct device *dev)

{

	struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);

	if (device_may_wakeup(dev))

		enable_irq_wake(pwrkey->irq);

	return 0;

}

static int __maybe_unused pm8941_pwrkey_resume(struct device *dev)

{

	struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);

	if (device_may_wakeup(dev))

		disable_irq_wake(pwrkey->irq);

	return 0;

}

static SIMPLE_DEV_PM_OPS(pm8941_pwr_key_pm_ops,

			 pm8941_pwrkey_suspend, pm8941_pwrkey_resume);

static int pm8941_pwrkey_probe(struct platform_device *pdev)

{

	struct pm8941_pwrkey *pwrkey;

	bool pull_up;

	u32 req_delay;

	int error;

	if (of_property_read_u32(pdev->dev.of_node, "debounce", &req_delay))

		req_delay = 15625;

	if (req_delay > 2000000 || req_delay == 0) {

		dev_err(&pdev->dev, "invalid debounce time: %u\n", req_delay);

		return -EINVAL;

	}

	pull_up = of_property_read_bool(pdev->dev.of_node, "bias-pull-up");

	pwrkey = devm_kzalloc(&pdev->dev, sizeof(*pwrkey), GFP_KERNEL);

	if (!pwrkey)

		return -ENOMEM;

	pwrkey->dev = &pdev->dev;

	pwrkey->regmap = dev_get_regmap(pdev->dev.parent, NULL);

	if (!pwrkey->regmap) {

		dev_err(&pdev->dev, "failed to locate regmap\n");

		return -ENODEV;

	}

	pwrkey->irq = platform_get_irq(pdev, 0);

	if (pwrkey->irq < 0) {

		dev_err(&pdev->dev, "failed to get irq\n");

		return pwrkey->irq;

	}

	error = of_property_read_u32(pdev->dev.of_node, "reg",

				     &pwrkey->baseaddr);

	if (error)

		return error;

	error = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_REV2,

			    &pwrkey->revision);

	if (error) {

		dev_err(&pdev->dev, "failed to set debounce: %d\n", error);

		return error;

	}

	pwrkey->input = devm_input_allocate_device(&pdev->dev);

	if (!pwrkey->input) {

		dev_dbg(&pdev->dev, "unable to allocate input device\n");

		return -ENOMEM;

	}

	input_set_capability(pwrkey->input, EV_KEY, KEY_POWER);

	pwrkey->input->name = "pm8941_pwrkey";

	pwrkey->input->phys = "pm8941_pwrkey/input0";

	req_delay = (req_delay << 6) / USEC_PER_SEC;

	req_delay = ilog2(req_delay);

	error = regmap_update_bits(pwrkey->regmap,

				   pwrkey->baseaddr + PON_DBC_CTL,

				   PON_DBC_DELAY_MASK,

				   req_delay);

	if (error) {

		dev_err(&pdev->dev, "failed to set debounce: %d\n", error);

		return error;

	}

	error = regmap_update_bits(pwrkey->regmap,

				   pwrkey->baseaddr + PON_PULL_CTL,

				   PON_KPDPWR_PULL_UP,

				   pull_up ? PON_KPDPWR_PULL_UP : 0);

	if (error) {

		dev_err(&pdev->dev, "failed to set pull: %d\n", error);

		return error;

	}

	error = devm_request_threaded_irq(&pdev->dev, pwrkey->irq,

					  NULL, pm8941_pwrkey_irq,

					  IRQF_ONESHOT,

					  "pm8941_pwrkey", pwrkey);

	if (error) {

		dev_err(&pdev->dev, "failed requesting IRQ: %d\n", error);

		return error;

	}

	error = input_register_device(pwrkey->input);

	if (error) {

		dev_err(&pdev->dev, "failed to register input device: %d\n",

			error);

		return error;

	}

	pwrkey->reboot_notifier.notifier_call = pm8941_reboot_notify,

	error = register_reboot_notifier(&pwrkey->reboot_notifier);

	if (error) {

		dev_err(&pdev->dev, "failed to register reboot notifier: %d\n",

			error);

		return error;

	}

	platform_set_drvdata(pdev, pwrkey);

	device_init_wakeup(&pdev->dev, 1);

	return 0;

}

static int pm8941_pwrkey_remove(struct platform_device *pdev)

{

	struct pm8941_pwrkey *pwrkey = platform_get_drvdata(pdev);

	device_init_wakeup(&pdev->dev, 0);

	unregister_reboot_notifier(&pwrkey->reboot_notifier);

	return 0;

}

static const struct of_device_id pm8941_pwr_key_id_table[] = {

	{ .compatible = "qcom,pm8941-pwrkey" },

	{ }

};

MODULE_DEVICE_TABLE(of, pm8941_pwr_key_id_table);

static struct platform_driver pm8941_pwrkey_driver = {

	.probe = pm8941_pwrkey_probe,

	.remove = pm8941_pwrkey_remove,

	.driver = {

		.name = "pm8941-pwrkey",

		.pm = &pm8941_pwr_key_pm_ops,

		.of_match_table = of_match_ptr(pm8941_pwr_key_id_table),

	},

};

module_platform_driver(pm8941_pwrkey_driver);

MODULE_DESCRIPTION("PM8941 Power Key driver");

MODULE_LICENSE("GPL v2");