Re: [PATCH 6/8] input: stpmu1: add stpmu1 onkey driver

From: Dmitry Torokhov
Date: Mon Aug 06 2018 - 18:47:44 EST


Hi Pascal,

On Thu, Jul 05, 2018 at 03:14:24PM +0000, Pascal PAILLET-LME wrote:
> From: pascal paillet <p.paillet@xxxxxx>
>
> The stpmu1 pmic is able to manage an onkey button. This driver exposes
> the stpmu1 onkey as an input device. It can also be configured to
> shut-down the power supplies on a long key-press with an adjustable
> duration.
>
> Signed-off-by: pascal paillet <p.paillet@xxxxxx>
> ---
> drivers/input/misc/Kconfig | 11 ++
> drivers/input/misc/Makefile | 2 +
> drivers/input/misc/stpmu1_onkey.c | 321 ++++++++++++++++++++++++++++++++++++++
> 3 files changed, 334 insertions(+)
> create mode 100644 drivers/input/misc/stpmu1_onkey.c
>
> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
> index c25606e..d020971 100644
> --- a/drivers/input/misc/Kconfig
> +++ b/drivers/input/misc/Kconfig
> @@ -841,4 +841,15 @@ config INPUT_RAVE_SP_PWRBUTTON
> To compile this driver as a module, choose M here: the
> module will be called rave-sp-pwrbutton.
>
> +config INPUT_STPMU1_ONKEY
> + tristate "STPMU1 PMIC Onkey support"
> + depends on MFD_STPMU1
> + help
> + Say Y to enable support of onkey embedded into STPMU1 PMIC. onkey
> + can be used to wakeup from low power modes and force a shut-down on
> + long press.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called stpmu1_onkey.
> +
> endif
> diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
> index 72cde28..cc60dc1 100644
> --- a/drivers/input/misc/Makefile
> +++ b/drivers/input/misc/Makefile
> @@ -70,6 +70,7 @@ obj-$(CONFIG_INPUT_SGI_BTNS) += sgi_btns.o
> obj-$(CONFIG_INPUT_SIRFSOC_ONKEY) += sirfsoc-onkey.o
> obj-$(CONFIG_INPUT_SOC_BUTTON_ARRAY) += soc_button_array.o
> obj-$(CONFIG_INPUT_SPARCSPKR) += sparcspkr.o
> +obj-$(CONFIG_INPUT_STPMU1_ONKEY) += stpmu1_onkey.o
> obj-$(CONFIG_INPUT_TPS65218_PWRBUTTON) += tps65218-pwrbutton.o
> obj-$(CONFIG_INPUT_TWL4030_PWRBUTTON) += twl4030-pwrbutton.o
> obj-$(CONFIG_INPUT_TWL4030_VIBRA) += twl4030-vibra.o
> @@ -80,3 +81,4 @@ obj-$(CONFIG_INPUT_WM831X_ON) += wm831x-on.o
> obj-$(CONFIG_INPUT_XEN_KBDDEV_FRONTEND) += xen-kbdfront.o
> obj-$(CONFIG_INPUT_YEALINK) += yealink.o
> obj-$(CONFIG_INPUT_IDEAPAD_SLIDEBAR) += ideapad_slidebar.o
> +
> diff --git a/drivers/input/misc/stpmu1_onkey.c b/drivers/input/misc/stpmu1_onkey.c
> new file mode 100644
> index 0000000..084a31f
> --- /dev/null
> +++ b/drivers/input/misc/stpmu1_onkey.c
> @@ -0,0 +1,321 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) STMicroelectronics 2018 - All Rights Reserved
> + * Author: Philippe Peurichard <philippe.peurichard@xxxxxx>,
> + * Pascal Paillet <p.paillet@xxxxxx> for STMicroelectronics.
> + */
> +
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/mfd/stpmu1.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +
> +/**
> + * struct stpmu1_onkey - OnKey data
> + * @pmic: pointer to STPMU1 PMIC device
> + * @input_dev: pointer to input device
> + * @irq_falling: irq that we are hooked on to
> + * @irq_rising: irq that we are hooked on to
> + */
> +struct stpmu1_onkey {
> + struct stpmu1_dev *pmic;
> + struct input_dev *input_dev;
> + int irq_falling;
> + int irq_rising;
> +};
> +
> +/**
> + * struct pmic_onkey_config - configuration of pmic PONKEYn
> + * @turnoff_enabled: value to enable turnoff condition
> + * @cc_flag_clear: value to clear CC flag in case of PowerOff
> + * trigger by longkey press
> + * @onkey_pullup_val: value of PONKEY PullUp (active or inactive)
> + * @long_press_time_val: value for long press h/w shutdown event
> + */
> +struct pmic_onkey_config {
> + bool turnoff_enabled;
> + bool cc_flag_clear;
> + u8 onkey_pullup_val;
> + u8 long_press_time_val;
> +};
> +
> +/**
> + * onkey_falling_irq() - button press isr
> + * @irq: irq
> + * @pmic_onkey: onkey device
> + *
> + * Return: IRQ_HANDLED
> + */

This is internal driver functions, I do not see the need for kernel-doc
style comments (or any comments for this one to be honest).

> +static irqreturn_t onkey_falling_irq(int irq, void *ponkey)
> +{
> + struct stpmu1_onkey *onkey = ponkey;
> + struct input_dev *input_dev = onkey->input_dev;
> +
> + input_report_key(input_dev, KEY_POWER, 1);
> + pm_wakeup_event(input_dev->dev.parent, 0);
> + input_sync(input_dev);
> +
> + dev_dbg(&input_dev->dev, "Pwr Onkey Falling Interrupt received\n");
> +
> + return IRQ_HANDLED;
> +}
> +
> +/**
> + * onkey_rising_irq() - button released isr
> + * @irq: irq
> + * @pmic_onkey: onkey device
> + *
> + * Return: IRQ_HANDLED
> + */
> +static irqreturn_t onkey_rising_irq(int irq, void *ponkey)
> +{
> + struct stpmu1_onkey *onkey = ponkey;
> + struct input_dev *input_dev = onkey->input_dev;
> +
> + input_report_key(input_dev, KEY_POWER, 0);
> + pm_wakeup_event(input_dev->dev.parent, 0);
> + input_sync(input_dev);
> +
> + dev_dbg(&input_dev->dev, "Pwr Onkey Rising Interrupt received\n");
> +
> + return IRQ_HANDLED;
> +}
> +
> +/**
> + * stpmu1_onkey_dt_params() - device tree parameter parser
> + * @pdev: platform device for the PONKEY
> + * @onkey: pointer to onkey driver data
> + * @config: configuration params to be filled up
> + */
> +static int stpmu1_onkey_dt_params(struct platform_device *pdev,
> + struct stpmu1_onkey *onkey,
> + struct pmic_onkey_config *config)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *np;
> + u32 val;
> +
> + np = dev->of_node;
> + if (!np)
> + return -EINVAL;

Is this possible?

> +
> + onkey->irq_falling = platform_get_irq_byname(pdev, "onkey-falling");
> + if (onkey->irq_falling < 0) {
> + dev_err(dev, "failed: request IRQ onkey-falling %d",

Some of your messages use \n, some don't. I'd rather they all did.

> + onkey->irq_falling);
> + return onkey->irq_falling;
> + }
> +
> + onkey->irq_rising = platform_get_irq_byname(pdev, "onkey-rising");
> + if (onkey->irq_rising < 0) {
> + dev_err(dev, "failed: request IRQ onkey-rising %d",
> + onkey->irq_rising);
> + return onkey->irq_rising;
> + }
> +
> + if (!of_property_read_u32(np, "st,onkey-long-press-seconds", &val)) {
> + if (val >= 1 && val <= 16) {
> + config->long_press_time_val = (16 - val);
> + } else {
> + dev_warn(dev,
> + "Invalid range of long key pressed timer %d (<16)\n\r",

Why \n\r?

> + val);
> + }
> + }
> + if (of_get_property(np, "st,onkey-pwroff-enabled", NULL))
> + config->turnoff_enabled = true;
> +
> + if (of_get_property(np, "st,onkey-clear-cc-flag", NULL))
> + config->cc_flag_clear = true;
> +
> + if (of_get_property(np, "st,onkey-pu-inactive", NULL))
> + config->onkey_pullup_val = PONKEY_PU_ACTIVE;

Even though the driver is only used in OF systems, I wonder if we should
not be using generic device property API.

> +
> + dev_dbg(dev, "onkey-switch-off duration=%d seconds\n",
> + config->long_press_time_val);
> +
> + return 0;
> +}
> +
> +/**
> + * stpmu1_onkey_probe() - probe
> + * @pdev: platform device for the PONKEY
> + *
> + * Return: 0 for successful probe else appropriate error
> + */
> +static int stpmu1_onkey_probe(struct platform_device *pdev)
> +{
> + struct stpmu1_dev *pmic = dev_get_drvdata(pdev->dev.parent);
> + struct device *dev = &pdev->dev;
> + struct input_dev *input_dev;
> + struct stpmu1_onkey *onkey;
> + struct pmic_onkey_config config;
> + unsigned int val = 0;
> + int ret;

Call this variable "error" please.

> +
> + onkey = devm_kzalloc(dev, sizeof(*onkey), GFP_KERNEL);
> + if (!onkey)
> + return -ENOMEM;
> +
> + memset(&config, 0, sizeof(struct pmic_onkey_config));
> + ret = stpmu1_onkey_dt_params(pdev, onkey, &config);
> + if (ret < 0)

stpmu1_onkey_dt_params() does not return positives (good) so:

if (error)
return error;

> + goto err;
> +
> + input_dev = devm_input_allocate_device(dev);
> + if (!input_dev) {
> + dev_err(dev, "Can't allocate Pwr Onkey Input Device\n");
> + ret = -ENOMEM;
> + goto err;
> + }
> +
> + input_dev->name = "pmic_onkey";
> + input_dev->phys = "pmic_onkey/input0";
> + input_dev->dev.parent = dev;

This is already set by devm_input_allocate_device().

> +
> + input_set_capability(input_dev, EV_KEY, KEY_POWER);
> +
> + /* Setup Power Onkey Hardware parameters (long key press)*/
> + val = (config.long_press_time_val & PONKEY_TURNOFF_TIMER_MASK);
> + if (config.turnoff_enabled)
> + val |= PONKEY_PWR_OFF;
> + if (config.cc_flag_clear)
> + val |= PONKEY_CC_FLAG_CLEAR;
> + ret = regmap_update_bits(pmic->regmap, PKEY_TURNOFF_CR,
> + PONKEY_TURNOFF_MASK, val);
> + if (ret) {
> + dev_err(dev, "LONG_PRESS_KEY_UPDATE failed: %d\n", ret);
> + goto err;

You are using all managed resources, so "return error" directly, no need
to just to error unwinding path.

> + }
> +
> + ret = regmap_update_bits(pmic->regmap, PADS_PULL_CR,
> + PONKEY_PU_ACTIVE,
> + config.onkey_pullup_val);
> +
> + if (ret) {
> + dev_err(dev, "ONKEY Pads configuration failed: %d\n", ret);
> + goto err;
> + }
> +
> + onkey->pmic = pmic;
> + onkey->input_dev = input_dev;
> +
> + ret = devm_request_threaded_irq(dev, onkey->irq_falling, NULL,

Why does this need to be threaded? The isr does not seem to be calling
any APIs that may wait.

> + onkey_falling_irq,
> + IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> + dev_name(dev), onkey);
> + if (ret) {
> + dev_err(dev, "Can't get IRQ for Onkey Falling edge: %d\n", ret);
> + goto err;
> + }
> +
> + ret = devm_request_threaded_irq(dev, onkey->irq_rising, NULL,
> + onkey_rising_irq,
> + IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> + dev_name(dev), onkey);
> + if (ret) {
> + dev_err(dev, "Can't get IRQ for Onkey Rising edge: %d\n", ret);
> + goto err;
> + }
> +
> + ret = input_register_device(input_dev);
> + if (ret) {
> + dev_err(dev, "Can't register power button: %d\n", ret);
> + goto err;
> + }
> +
> + platform_set_drvdata(pdev, onkey);
> + device_init_wakeup(dev, true);
> +
> + dev_dbg(dev, "PMIC Pwr Onkey driver probed\n");

I'd rather dropped this. Input core will print when registering device
already.

> +
> +err:
> + return ret;
> +}
> +
> +/**
> + * stpmu1_onkey_remove() - Cleanup on removal
> + * @pdev: platform device for the button
> + *
> + * Return: 0
> + */
> +static int stpmu1_onkey_remove(struct platform_device *pdev)
> +{
> + struct stpmu1_onkey *onkey = platform_get_drvdata(pdev);
> +
> + input_unregister_device(onkey->input_dev);

You are using managed input device, so this call is not needed. You
should be able to remove entire stpmu1_onkey_remove().

> + return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP

You annotated suspend/resume methods with __maybe_unused, so this guard
is not needed.

> +
> +/**
> + * pmic_onkey_suspend() - suspend handler
> + * @dev: power button device
> + *
> + * Cancel all pending work items for the power button, setup irq for wakeup
> + *
> + * Return: 0
> + */
> +static int __maybe_unused stpmu1_onkey_suspend(struct device *dev)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct stpmu1_onkey *onkey = platform_get_drvdata(pdev);
> +
> + if (device_may_wakeup(dev)) {
> + enable_irq_wake(onkey->irq_falling);
> + enable_irq_wake(onkey->irq_rising);
> + }
> + return 0;
> +}
> +
> +/**
> + * pmic_onkey_resume() - resume handler
> + * @dev: power button device
> + *
> + * Just disable the wakeup capability of irq here.
> + *
> + * Return: 0
> + */
> +static int __maybe_unused stpmu1_onkey_resume(struct device *dev)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct stpmu1_onkey *onkey = platform_get_drvdata(pdev);
> +
> + if (device_may_wakeup(dev)) {
> + disable_irq_wake(onkey->irq_falling);
> + disable_irq_wake(onkey->irq_rising);
> + }
> + return 0;
> +}
> +
> +#endif
> +
> +static SIMPLE_DEV_PM_OPS(stpmu1_onkey_pm,
> + stpmu1_onkey_suspend,
> + stpmu1_onkey_resume);
> +
> +static const struct of_device_id of_stpmu1_onkey_match[] = {
> + { .compatible = "st,stpmu1-onkey" },
> + { },
> +};
> +
> +MODULE_DEVICE_TABLE(of, of_stpmu1_onkey_match);
> +
> +static struct platform_driver stpmu1_onkey_driver = {
> + .probe = stpmu1_onkey_probe,
> + .remove = stpmu1_onkey_remove,
> + .driver = {
> + .name = "stpmu1_onkey",
> + .of_match_table = of_match_ptr(of_stpmu1_onkey_match),
> + .pm = &stpmu1_onkey_pm,
> + },
> +};
> +module_platform_driver(stpmu1_onkey_driver);
> +
> +MODULE_DESCRIPTION("Onkey driver for STPMU1");
> +MODULE_LICENSE("GPL");

To match your SPDX notice this should be MODULE_LICENSE("GPL v2").

> +MODULE_AUTHOR("philippe.peurichard@xxxxxx>");
> --
> 1.9.1

Thanks.

--
Dmitry