// SPDX-License-Identifier: GPL-2.0+
//
// Driver for the IMX SNVS ON/OFF Power Key
// Copyright (C) 2015 Freescale Semiconductor, Inc. All Rights Reserved.
#include <linux/clk.h>
#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/pm_wakeirq.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#define SNVS_HPVIDR1_REG 0xBF8
#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;
u8 minor_rev;
};
static void imx_imx_snvs_check_for_events(struct timer_list *t)
{
struct pwrkey_drv_data *pdata = from_timer(pdata, t, check_timer);
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);
struct input_dev *input = pdata->input;
u32 lp_status;
pm_wakeup_event(input->dev.parent, 0);
regmap_read(pdata->snvs, SNVS_LPSR_REG, &lp_status);
if (lp_status & SNVS_LPSR_SPO) {
if (pdata->minor_rev == 0) {
/*
* The first generation i.MX6 SoCs only sends an
* interrupt on button release. To mimic power-key
* usage, we'll prepend a press event.
*/
input_report_key(input, pdata->keycode, 1);
input_sync(input);
input_report_key(input, pdata->keycode, 0);
input_sync(input);
pm_relax(input->dev.parent);
} else {
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;
struct input_dev *input;
struct device_node *np;
struct clk *clk;
int error;
u32 vid;
/* 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 (IS_ERR(pdata->snvs)) {
dev_err(&pdev->dev, "Can't get snvs syscon\n");
return PTR_ERR(pdata->snvs);
}
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");
}
clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
if (IS_ERR(clk)) {
dev_err(&pdev->dev, "Failed to get snvs clock (%pe)\n", clk);
return PTR_ERR(clk);
}
pdata->wakeup = of_property_read_bool(np, "wakeup-source");
pdata->irq = platform_get_irq(pdev, 0);
if (pdata->irq < 0)
return -EINVAL;
regmap_read(pdata->snvs, SNVS_HPVIDR1_REG, &vid);
pdata->minor_rev = vid & 0xff;
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);
timer_setup(&pdata->check_timer, imx_imx_snvs_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 = "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;
}
pdata->input = input;
platform_set_drvdata(pdev, pdata);
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");
return error;
}
device_init_wakeup(&pdev->dev, pdata->wakeup);
error = dev_pm_set_wake_irq(&pdev->dev, pdata->irq);
if (error)
dev_err(&pdev->dev, "irq wake enable failed.\n");
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 struct platform_driver imx_snvs_pwrkey_driver = {
.driver = {
.name = "snvs_pwrkey",
.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");
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