v4.19.13 snapshot.
diff --git a/drivers/gpio/gpio-menz127.c b/drivers/gpio/gpio-menz127.c
new file mode 100644
index 0000000..b263532
--- /dev/null
+++ b/drivers/gpio/gpio-menz127.c
@@ -0,0 +1,216 @@
+/*
+ * MEN 16Z127 GPIO driver
+ *
+ * Copyright (C) 2016 MEN Mikroelektronik GmbH (www.men.de)
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; version 2 of the License.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/mcb.h>
+#include <linux/bitops.h>
+#include <linux/gpio/driver.h>
+
+#define MEN_Z127_CTRL	0x00
+#define MEN_Z127_PSR	0x04
+#define MEN_Z127_IRQR	0x08
+#define MEN_Z127_GPIODR	0x0c
+#define MEN_Z127_IER1	0x10
+#define MEN_Z127_IER2	0x14
+#define MEN_Z127_DBER	0x18
+#define MEN_Z127_ODER	0x1C
+#define GPIO_TO_DBCNT_REG(gpio)	((gpio * 4) + 0x80)
+
+#define MEN_Z127_DB_MIN_US	50
+/* 16 bit compare register. Each bit represents 50us */
+#define MEN_Z127_DB_MAX_US	(0xffff * MEN_Z127_DB_MIN_US)
+#define MEN_Z127_DB_IN_RANGE(db)	((db >= MEN_Z127_DB_MIN_US) && \
+					 (db <= MEN_Z127_DB_MAX_US))
+
+struct men_z127_gpio {
+	struct gpio_chip gc;
+	void __iomem *reg_base;
+	struct resource *mem;
+};
+
+static int men_z127_debounce(struct gpio_chip *gc, unsigned gpio,
+			     unsigned debounce)
+{
+	struct men_z127_gpio *priv = gpiochip_get_data(gc);
+	struct device *dev = gc->parent;
+	unsigned int rnd;
+	u32 db_en, db_cnt;
+
+	if (!MEN_Z127_DB_IN_RANGE(debounce)) {
+		dev_err(dev, "debounce value %u out of range", debounce);
+		return -EINVAL;
+	}
+
+	if (debounce > 0) {
+		/* round up or down depending on MSB-1 */
+		rnd = fls(debounce) - 1;
+
+		if (rnd && (debounce & BIT(rnd - 1)))
+			debounce = roundup(debounce, MEN_Z127_DB_MIN_US);
+		else
+			debounce = rounddown(debounce, MEN_Z127_DB_MIN_US);
+
+		if (debounce > MEN_Z127_DB_MAX_US)
+			debounce = MEN_Z127_DB_MAX_US;
+
+		/* 50us per register unit */
+		debounce /= 50;
+	}
+
+	spin_lock(&gc->bgpio_lock);
+
+	db_en = readl(priv->reg_base + MEN_Z127_DBER);
+
+	if (debounce == 0) {
+		db_en &= ~BIT(gpio);
+		db_cnt = 0;
+	} else {
+		db_en |= BIT(gpio);
+		db_cnt = debounce;
+	}
+
+	writel(db_en, priv->reg_base + MEN_Z127_DBER);
+	writel(db_cnt, priv->reg_base + GPIO_TO_DBCNT_REG(gpio));
+
+	spin_unlock(&gc->bgpio_lock);
+
+	return 0;
+}
+
+static int men_z127_set_single_ended(struct gpio_chip *gc,
+				     unsigned offset,
+				     enum pin_config_param param)
+{
+	struct men_z127_gpio *priv = gpiochip_get_data(gc);
+	u32 od_en;
+
+	spin_lock(&gc->bgpio_lock);
+	od_en = readl(priv->reg_base + MEN_Z127_ODER);
+
+	if (param == PIN_CONFIG_DRIVE_OPEN_DRAIN)
+		od_en |= BIT(offset);
+	else
+		/* Implicitly PIN_CONFIG_DRIVE_PUSH_PULL */
+		od_en &= ~BIT(offset);
+
+	writel(od_en, priv->reg_base + MEN_Z127_ODER);
+	spin_unlock(&gc->bgpio_lock);
+
+	return 0;
+}
+
+static int men_z127_set_config(struct gpio_chip *gc, unsigned offset,
+			       unsigned long config)
+{
+	enum pin_config_param param = pinconf_to_config_param(config);
+
+	switch (param) {
+	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
+	case PIN_CONFIG_DRIVE_PUSH_PULL:
+		return men_z127_set_single_ended(gc, offset, param);
+
+	case PIN_CONFIG_INPUT_DEBOUNCE:
+		return men_z127_debounce(gc, offset,
+			pinconf_to_config_argument(config));
+
+	default:
+		break;
+	}
+
+	return -ENOTSUPP;
+}
+
+static int men_z127_probe(struct mcb_device *mdev,
+			  const struct mcb_device_id *id)
+{
+	struct men_z127_gpio *men_z127_gpio;
+	struct device *dev = &mdev->dev;
+	int ret;
+
+	men_z127_gpio = devm_kzalloc(dev, sizeof(struct men_z127_gpio),
+				     GFP_KERNEL);
+	if (!men_z127_gpio)
+		return -ENOMEM;
+
+	men_z127_gpio->mem = mcb_request_mem(mdev, dev_name(dev));
+	if (IS_ERR(men_z127_gpio->mem)) {
+		dev_err(dev, "failed to request device memory");
+		return PTR_ERR(men_z127_gpio->mem);
+	}
+
+	men_z127_gpio->reg_base = ioremap(men_z127_gpio->mem->start,
+					  resource_size(men_z127_gpio->mem));
+	if (men_z127_gpio->reg_base == NULL) {
+		ret = -ENXIO;
+		goto err_release;
+	}
+
+	mcb_set_drvdata(mdev, men_z127_gpio);
+
+	ret = bgpio_init(&men_z127_gpio->gc, &mdev->dev, 4,
+			 men_z127_gpio->reg_base + MEN_Z127_PSR,
+			 men_z127_gpio->reg_base + MEN_Z127_CTRL,
+			 NULL,
+			 men_z127_gpio->reg_base + MEN_Z127_GPIODR,
+			 NULL, 0);
+	if (ret)
+		goto err_unmap;
+
+	men_z127_gpio->gc.set_config = men_z127_set_config;
+
+	ret = gpiochip_add_data(&men_z127_gpio->gc, men_z127_gpio);
+	if (ret) {
+		dev_err(dev, "failed to register MEN 16Z127 GPIO controller");
+		goto err_unmap;
+	}
+
+	dev_info(dev, "MEN 16Z127 GPIO driver registered");
+
+	return 0;
+
+err_unmap:
+	iounmap(men_z127_gpio->reg_base);
+err_release:
+	mcb_release_mem(men_z127_gpio->mem);
+	return ret;
+}
+
+static void men_z127_remove(struct mcb_device *mdev)
+{
+	struct men_z127_gpio *men_z127_gpio = mcb_get_drvdata(mdev);
+
+	gpiochip_remove(&men_z127_gpio->gc);
+	iounmap(men_z127_gpio->reg_base);
+	mcb_release_mem(men_z127_gpio->mem);
+}
+
+static const struct mcb_device_id men_z127_ids[] = {
+	{ .device = 0x7f },
+	{ }
+};
+MODULE_DEVICE_TABLE(mcb, men_z127_ids);
+
+static struct mcb_driver men_z127_driver = {
+	.driver = {
+		.name = "z127-gpio",
+	},
+	.probe = men_z127_probe,
+	.remove = men_z127_remove,
+	.id_table = men_z127_ids,
+};
+module_mcb_driver(men_z127_driver);
+
+MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
+MODULE_DESCRIPTION("MEN 16z127 GPIO Controller");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("mcb:16z127");