// SPDX-License-Identifier: GPL-2.0+
//
// Copyright 2022 NXP.
#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/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/pm_wakeirq.h>
#include <linux/regmap.h>
#define BBNSM_CTRL 0x8
#define BBNSM_INT_EN 0x10
#define BBNSM_EVENTS 0x14
#define BBNSM_PAD_CTRL 0x24
#define BBNSM_BTN_PRESSED BIT(7)
#define BBNSM_PWR_ON BIT(6)
#define BBNSM_BTN_OFF BIT(5)
#define BBNSM_EMG_OFF BIT(4)
#define BBNSM_PWRKEY_EVENTS (BBNSM_PWR_ON | BBNSM_BTN_OFF | BBNSM_EMG_OFF)
#define BBNSM_DP_EN BIT(24)
#define DEBOUNCE_TIME 30
#define REPEAT_INTERVAL 60
struct bbnsm_pwrkey {
struct regmap *regmap;
int irq;
int keycode;
int keystate; /* 1:pressed */
bool suspended;
struct timer_list check_timer;
struct input_dev *input;
};
static void bbnsm_pwrkey_check_for_events(struct timer_list *t)
{
struct bbnsm_pwrkey *bbnsm = from_timer(bbnsm, t, check_timer);
struct input_dev *input = bbnsm->input;
u32 state;
regmap_read(bbnsm->regmap, BBNSM_EVENTS, &state);
state = state & BBNSM_BTN_PRESSED ? 1 : 0;
/* only report new event if status changed */
if (state ^ bbnsm->keystate) {
bbnsm->keystate = state;
input_event(input, EV_KEY, bbnsm->keycode, state);
input_sync(input);
pm_relax(bbnsm->input->dev.parent);
}
/* repeat check if pressed long */
if (state)
mod_timer(&bbnsm->check_timer,
jiffies + msecs_to_jiffies(REPEAT_INTERVAL));
}
static irqreturn_t bbnsm_pwrkey_interrupt(int irq, void *dev_id)
{
struct platform_device *pdev = dev_id;
struct bbnsm_pwrkey *bbnsm = platform_get_drvdata(pdev);
struct input_dev *input = bbnsm->input;
u32 event;
regmap_read(bbnsm->regmap, BBNSM_EVENTS, &event);
if (!(event & BBNSM_BTN_OFF))
return IRQ_NONE;
pm_wakeup_event(bbnsm->input->dev.parent, 0);
/*
* Directly report key event after resume to make sure key press
* event is never missed.
*/
if (bbnsm->suspended) {
bbnsm->keystate = 1;
input_event(input, EV_KEY, bbnsm->keycode, 1);
input_sync(input);
/* Fire at most once per suspend/resume cycle */
bbnsm->suspended = false;
}
mod_timer(&bbnsm->check_timer,
jiffies + msecs_to_jiffies(DEBOUNCE_TIME));
/* clear PWR OFF */
regmap_write(bbnsm->regmap, BBNSM_EVENTS, BBNSM_BTN_OFF);
return IRQ_HANDLED;
}
static void bbnsm_pwrkey_act(void *pdata)
{
struct bbnsm_pwrkey *bbnsm = pdata;
timer_shutdown_sync(&bbnsm->check_timer);
}
static int bbnsm_pwrkey_probe(struct platform_device *pdev)
{
struct bbnsm_pwrkey *bbnsm;
struct input_dev *input;
struct device_node *np = pdev->dev.of_node;
int error;
bbnsm = devm_kzalloc(&pdev->dev, sizeof(*bbnsm), GFP_KERNEL);
if (!bbnsm)
return -ENOMEM;
bbnsm->regmap = syscon_node_to_regmap(np->parent);
if (IS_ERR(bbnsm->regmap)) {
dev_err(&pdev->dev, "bbnsm pwerkey get regmap failed\n");
return PTR_ERR(bbnsm->regmap);
}
if (device_property_read_u32(&pdev->dev, "linux,code",
&bbnsm->keycode)) {
bbnsm->keycode = KEY_POWER;
dev_warn(&pdev->dev, "key code is not specified, using default KEY_POWER\n");
}
bbnsm->irq = platform_get_irq(pdev, 0);
if (bbnsm->irq < 0)
return -EINVAL;
/* config the BBNSM power related register */
regmap_update_bits(bbnsm->regmap, BBNSM_CTRL, BBNSM_DP_EN, BBNSM_DP_EN);
/* clear the unexpected interrupt before driver ready */
regmap_write_bits(bbnsm->regmap, BBNSM_EVENTS, BBNSM_PWRKEY_EVENTS,
BBNSM_PWRKEY_EVENTS);
timer_setup(&bbnsm->check_timer, bbnsm_pwrkey_check_for_events, 0);
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 = "bbnsm-pwrkey/input0";
input->id.bustype = BUS_HOST;
input_set_capability(input, EV_KEY, bbnsm->keycode);
/* input customer action to cancel release timer */
error = devm_add_action(&pdev->dev, bbnsm_pwrkey_act, bbnsm);
if (error) {
dev_err(&pdev->dev, "failed to register remove action\n");
return error;
}
bbnsm->input = input;
platform_set_drvdata(pdev, bbnsm);
error = devm_request_irq(&pdev->dev, bbnsm->irq, bbnsm_pwrkey_interrupt,
IRQF_SHARED, pdev->name, pdev);
if (error) {
dev_err(&pdev->dev, "interrupt not available.\n");
return error;
}
error = input_register_device(input);
if (error) {
dev_err(&pdev->dev, "failed to register input device\n");
return error;
}
device_init_wakeup(&pdev->dev, true);
error = dev_pm_set_wake_irq(&pdev->dev, bbnsm->irq);
if (error)
dev_warn(&pdev->dev, "irq wake enable failed.\n");
return 0;
}
static int __maybe_unused bbnsm_pwrkey_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct bbnsm_pwrkey *bbnsm = platform_get_drvdata(pdev);
bbnsm->suspended = true;
return 0;
}
static int __maybe_unused bbnsm_pwrkey_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct bbnsm_pwrkey *bbnsm = platform_get_drvdata(pdev);
bbnsm->suspended = false;
return 0;
}
static SIMPLE_DEV_PM_OPS(bbnsm_pwrkey_pm_ops, bbnsm_pwrkey_suspend,
bbnsm_pwrkey_resume);
static const struct of_device_id bbnsm_pwrkey_ids[] = {
{ .compatible = "nxp,imx93-bbnsm-pwrkey" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, bbnsm_pwrkey_ids);
static struct platform_driver bbnsm_pwrkey_driver = {
.driver = {
.name = "bbnsm_pwrkey",
.pm = &bbnsm_pwrkey_pm_ops,
.of_match_table = bbnsm_pwrkey_ids,
},
.probe = bbnsm_pwrkey_probe,
};
module_platform_driver(bbnsm_pwrkey_driver);
MODULE_AUTHOR("Jacky Bai <[email protected]>");
MODULE_DESCRIPTION("NXP bbnsm power key Driver");
MODULE_LICENSE("GPL");
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