--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (C) 2018 BayLibre SAS
+// Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
+//
+// ONKEY driver for MAXIM 77650/77651 charger/power-supply.
+
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/max77650.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define MAX77650_ONKEY_MODE_MASK BIT(3)
+#define MAX77650_ONKEY_MODE_PUSH 0x00
+#define MAX77650_ONKEY_MODE_SLIDE BIT(3)
+
+struct max77650_onkey {
+ struct input_dev *input;
+ unsigned int code;
+};
+
+static irqreturn_t max77650_onkey_falling(int irq, void *data)
+{
+ struct max77650_onkey *onkey = data;
+
+ input_report_key(onkey->input, onkey->code, 0);
+ input_sync(onkey->input);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t max77650_onkey_rising(int irq, void *data)
+{
+ struct max77650_onkey *onkey = data;
+
+ input_report_key(onkey->input, onkey->code, 1);
+ input_sync(onkey->input);
+
+ return IRQ_HANDLED;
+}
+
+static int max77650_onkey_probe(struct platform_device *pdev)
+{
+ int irq_r, irq_f, error, mode;
+ struct max77650_onkey *onkey;
+ struct device *dev, *parent;
+ struct regmap *map;
+ unsigned int type;
+
+ dev = &pdev->dev;
+ parent = dev->parent;
+
+ map = dev_get_regmap(parent, NULL);
+ if (!map)
+ return -ENODEV;
+
+ onkey = devm_kzalloc(dev, sizeof(*onkey), GFP_KERNEL);
+ if (!onkey)
+ return -ENOMEM;
+
+ error = device_property_read_u32(dev, "linux,code", &onkey->code);
+ if (error)
+ onkey->code = KEY_POWER;
+
+ if (device_property_read_bool(dev, "maxim,onkey-slide")) {
+ mode = MAX77650_ONKEY_MODE_SLIDE;
+ type = EV_SW;
+ } else {
+ mode = MAX77650_ONKEY_MODE_PUSH;
+ type = EV_KEY;
+ }
+
+ error = regmap_update_bits(map, MAX77650_REG_CNFG_GLBL,
+ MAX77650_ONKEY_MODE_MASK, mode);
+ if (error)
+ return error;
+
+ irq_f = platform_get_irq_byname(pdev, "nEN_F");
+ if (irq_f < 0)
+ return irq_f;
+
+ irq_r = platform_get_irq_byname(pdev, "nEN_R");
+ if (irq_r < 0)
+ return irq_r;
+
+ onkey->input = devm_input_allocate_device(dev);
+ if (!onkey->input)
+ return -ENOMEM;
+
+ onkey->input->name = "max77650_onkey";
+ onkey->input->phys = "max77650_onkey/input0";
+ onkey->input->id.bustype = BUS_I2C;
+ input_set_capability(onkey->input, type, onkey->code);
+
+ error = devm_request_any_context_irq(dev, irq_f, max77650_onkey_falling,
+ IRQF_ONESHOT, "onkey-down", onkey);
+ if (error < 0)
+ return error;
+
+ error = devm_request_any_context_irq(dev, irq_r, max77650_onkey_rising,
+ IRQF_ONESHOT, "onkey-up", onkey);
+ if (error < 0)
+ return error;
+
+ return input_register_device(onkey->input);
+}
+
+static struct platform_driver max77650_onkey_driver = {
+ .driver = {
+ .name = "max77650-onkey",
+ },
+ .probe = max77650_onkey_probe,
+};
+module_platform_driver(max77650_onkey_driver);
+
+MODULE_DESCRIPTION("MAXIM 77650/77651 ONKEY driver");
+MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>");
+MODULE_LICENSE("GPL v2");