Re: [PATCH v5 4/6] input: keyboard: imx: add snvs power key driver

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Wed, May 27, 2015 at 12:26:00AM +0800, Frank.Li@freescale.com wrote:
> From: Robin Gong <b38343@freescale.com>
> 
> add snvs power key driver.
> It work in imx chips after i.mx6sx
> 
> ON/OFF key used power on/off whole system.
> This driver make it wakeup from suspend state when short press
> ON/OFF key.
> 
> Long time press will trig SNVS power off chip without software
> intervention.
> 
> Signed-off-by: Robin Gong <b38343@freescale.com>
> Signed-off-by: Frank Li <Frank.Li@freescale.com>

Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

> ---
>  drivers/input/keyboard/Kconfig       |  11 ++
>  drivers/input/keyboard/Makefile      |   1 +
>  drivers/input/keyboard/snvs_pwrkey.c | 227 +++++++++++++++++++++++++++++++++++
>  3 files changed, 239 insertions(+)
>  create mode 100644 drivers/input/keyboard/snvs_pwrkey.c
> 
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index 106fbac..61b3fab 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -400,6 +400,17 @@ config KEYBOARD_MPR121
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called mpr121_touchkey.
>  
> +config KEYBOARD_SNVS_PWRKEY
> +	tristate "IMX SNVS Power Key Driver"
> +	depends on SOC_IMX6SX
> +	depends on OF
> +	help
> +	  This is the snvs powerkey driver for the Freescale i.MX application
> +	  processors that are newer than i.MX6 SX.
> +
> +	  To compile this driver as a module, choose M here; the
> +	  module will be called snvs_pwrkey.
> +
>  config KEYBOARD_IMX
>  	tristate "IMX keypad support"
>  	depends on ARCH_MXC
> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> index df28d55..1d416dd 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -51,6 +51,7 @@ obj-$(CONFIG_KEYBOARD_QT1070)           += qt1070.o
>  obj-$(CONFIG_KEYBOARD_QT2160)		+= qt2160.o
>  obj-$(CONFIG_KEYBOARD_SAMSUNG)		+= samsung-keypad.o
>  obj-$(CONFIG_KEYBOARD_SH_KEYSC)		+= sh_keysc.o
> +obj-$(CONFIG_KEYBOARD_SNVS_PWRKEY)	+= snvs_pwrkey.o
>  obj-$(CONFIG_KEYBOARD_SPEAR)		+= spear-keyboard.o
>  obj-$(CONFIG_KEYBOARD_STMPE)		+= stmpe-keypad.o
>  obj-$(CONFIG_KEYBOARD_STOWAWAY)		+= stowaway.o
> diff --git a/drivers/input/keyboard/snvs_pwrkey.c b/drivers/input/keyboard/snvs_pwrkey.c
> new file mode 100644
> index 0000000..512a1fc
> --- /dev/null
> +++ b/drivers/input/keyboard/snvs_pwrkey.c
> @@ -0,0 +1,227 @@
> +/*
> + * Driver for the IMX SNVS ON/OFF Power Key
> + * Copyright (C) 2015 Freescale Semiconductor, Inc. All Rights Reserved.
> + *
> + * The code contained herein is licensed under the GNU General Public
> + * License. You may obtain a copy of the GNU General Public License
> + * Version 2 or later at the following locations:
> + *
> + * http://www.opensource.org/licenses/gpl-license.html
> + * http://www.gnu.org/copyleft/gpl.html
> + */
> +
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/jiffies.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/regmap.h>
> +
> +#define SNVS_LPSR_REG	0x4C	/* LP Status Register */
> +#define SNVS_LPCR_REG	0x38	/* LP Control Register */
> +#define SNVS_HPSR_REG	0x14
> +#define SNVS_HPSR_BTN	BIT(6)
> +#define SNVS_LPSR_SPO	BIT(18)
> +#define SNVS_LPCR_DEP_EN BIT(5)
> +
> +#define DEBOUNCE_TIME 30
> +#define REPEAT_INTERVAL 60
> +
> +struct pwrkey_drv_data {
> +	struct regmap *snvs;
> +	int irq;
> +	int keycode;
> +	int keystate;  /* 1:pressed */
> +	int wakeup;
> +	struct timer_list check_timer;
> +	struct input_dev *input;
> +};
> +
> +static void imx_imx_snvs_check_for_events(unsigned long data)
> +{
> +	struct pwrkey_drv_data *pdata = (struct pwrkey_drv_data *) data;
> +	struct input_dev *input = pdata->input;
> +	u32 state;
> +
> +	regmap_read(pdata->snvs, SNVS_HPSR_REG, &state);
> +	state = state & SNVS_HPSR_BTN ? 1 : 0;
> +
> +	/* only report new event if status changed */
> +	if (state ^ pdata->keystate) {
> +		pdata->keystate = state;
> +		input_event(input, EV_KEY, pdata->keycode, state);
> +		input_sync(input);
> +		pm_relax(pdata->input->dev.parent);
> +	}
> +
> +	/* repeat check if pressed long */
> +	if (state) {
> +		mod_timer(&pdata->check_timer,
> +			  jiffies + msecs_to_jiffies(REPEAT_INTERVAL));
> +	}
> +}
> +
> +static irqreturn_t imx_snvs_pwrkey_interrupt(int irq, void *dev_id)
> +{
> +	struct platform_device *pdev = dev_id;
> +	struct pwrkey_drv_data *pdata = platform_get_drvdata(pdev);
> +	u32 lp_status;
> +
> +	pm_wakeup_event(pdata->input->dev.parent, 0);
> +
> +	regmap_read(pdata->snvs, SNVS_LPSR_REG, &lp_status);
> +	if (lp_status & SNVS_LPSR_SPO)
> +		mod_timer(&pdata->check_timer, jiffies + msecs_to_jiffies(DEBOUNCE_TIME));
> +
> +	/* clear SPO status */
> +	regmap_write(pdata->snvs, SNVS_LPSR_REG, SNVS_LPSR_SPO);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void imx_snvs_pwrkey_act(void *pdata)
> +{
> +	struct pwrkey_drv_data *pd = pdata;
> +
> +	del_timer_sync(&pd->check_timer);
> +}
> +
> +static int imx_snvs_pwrkey_probe(struct platform_device *pdev)
> +{
> +	struct pwrkey_drv_data *pdata = NULL;
> +	struct input_dev *input = NULL;
> +	struct device_node *np;
> +	int error;
> +
> +	/* Get SNVS register Page */
> +	np = pdev->dev.of_node;
> +	if (!np)
> +		return -ENODEV;
> +
> +	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
> +	if (!pdata)
> +		return -ENOMEM;
> +
> +	pdata->snvs = syscon_regmap_lookup_by_phandle(np, "regmap");;
> +
> +	if (!pdata->snvs) {
> +		dev_err(&pdev->dev, "Can't get snvs syscon\n");
> +		return -ENODEV;
> +	}
> +
> +	if (of_property_read_u32(np, "linux,keycode", &pdata->keycode)) {
> +		pdata->keycode = KEY_POWER;
> +		dev_warn(&pdev->dev, "KEY_POWER without setting in dts\n");
> +	}
> +
> +	pdata->wakeup = of_property_read_bool(np, "wakeup");
> +
> +	pdata->irq = platform_get_irq(pdev, 0);
> +	if (pdata->irq < 0) {
> +		dev_err(&pdev->dev, "no irq defined in platform data\n");
> +		return -EINVAL;
> +	}
> +
> +	regmap_update_bits(pdata->snvs, SNVS_LPCR_REG, SNVS_LPCR_DEP_EN, SNVS_LPCR_DEP_EN);
> +
> +	/* clear the unexpected interrupt before driver ready */
> +	regmap_write(pdata->snvs, SNVS_LPSR_REG, SNVS_LPSR_SPO);
> +
> +	setup_timer(&pdata->check_timer,
> +		    imx_imx_snvs_check_for_events, (unsigned long) pdata);
> +
> +	input = devm_input_allocate_device(&pdev->dev);
> +	if (!input) {
> +		dev_err(&pdev->dev, "failed to allocate the input device\n");
> +		return -ENOMEM;
> +	}
> +
> +	input->name = pdev->name;
> +	input->phys = "snvs-pwrkey/input0";
> +	input->id.bustype = BUS_HOST;
> +
> +	input_set_capability(input, EV_KEY, pdata->keycode);
> +
> +	/* input customer action to cancel release timer */
> +	error = devm_add_action(&pdev->dev, imx_snvs_pwrkey_act, pdata);
> +	if (error) {
> +		dev_err(&pdev->dev, "failed to register remove action\n");
> +		return error;
> +	}
> +
> +	error = devm_request_irq(&pdev->dev, pdata->irq,
> +			       imx_snvs_pwrkey_interrupt,
> +			       0, pdev->name, pdev);
> +
> +	if (error) {
> +		dev_err(&pdev->dev, "interrupt not available.\n");
> +		return error;
> +	}
> +
> +	error = input_register_device(input);
> +	if (error < 0) {
> +		dev_err(&pdev->dev, "failed to register input device\n");
> +		input_free_device(input);
> +		return error;
> +	}
> +
> +	pdata->input = input;
> +	platform_set_drvdata(pdev, pdata);
> +
> +	device_init_wakeup(&pdev->dev, pdata->wakeup);
> +
> +	return 0;
> +}
> +
> +static int imx_snvs_pwrkey_suspend(struct device *dev)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct pwrkey_drv_data *pdata = platform_get_drvdata(pdev);
> +
> +	if (device_may_wakeup(&pdev->dev))
> +		enable_irq_wake(pdata->irq);
> +
> +	return 0;
> +}
> +
> +static int imx_snvs_pwrkey_resume(struct device *dev)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct pwrkey_drv_data *pdata = platform_get_drvdata(pdev);
> +
> +	if (device_may_wakeup(&pdev->dev))
> +		disable_irq_wake(pdata->irq);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id imx_snvs_pwrkey_ids[] = {
> +	{ .compatible = "fsl,sec-v4.0-pwrkey" },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, imx_snvs_pwrkey_ids);
> +
> +static SIMPLE_DEV_PM_OPS(imx_snvs_pwrkey_pm_ops, imx_snvs_pwrkey_suspend,
> +				imx_snvs_pwrkey_resume);
> +
> +static struct platform_driver imx_snvs_pwrkey_driver = {
> +	.driver = {
> +		.name = "snvs_pwrkey",
> +		.pm     = &imx_snvs_pwrkey_pm_ops,
> +		.of_match_table = imx_snvs_pwrkey_ids,
> +	},
> +	.probe = imx_snvs_pwrkey_probe,
> +};
> +module_platform_driver(imx_snvs_pwrkey_driver);
> +
> +MODULE_AUTHOR("Freescale Semiconductor");
> +MODULE_DESCRIPTION("i.MX snvs power key Driver");
> +MODULE_LICENSE("GPL");
> -- 
> 1.9.1
> 

-- 
Dmitry