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Andreas Wernerlinusw
Andreas Werner
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linusw
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gpio: add driver for MEN 16Z127 GPIO controller
The 16Z127 is a 32bit GPIO controller on a MCB FPGA. Every single line can be configured as input and output. Push pull and open drain are supported as well as setting a debounce value for the input lines. Signed-off-by: Andreas Werner <andy@wernerandy.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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‎drivers/gpio/Kconfig

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@@ -270,6 +270,13 @@ config GPIO_MB86S7X
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help
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Say yes here to support the GPIO controller in Fujitsu MB86S70 SoCs.
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config GPIO_MENZ127
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tristate "MEN 16Z127 GPIO support"
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depends on MCB
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select GPIO_GENERIC
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help
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Say yes here to support the MEN 16Z127 GPIO Controller
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config GPIO_MM_LANTIQ
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bool "Lantiq Memory mapped GPIOs"
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depends on LANTIQ && SOC_XWAY

‎drivers/gpio/Makefile

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@@ -59,6 +59,7 @@ obj-$(CONFIG_GPIO_MAX7300) += gpio-max7300.o
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obj-$(CONFIG_GPIO_MAX7301) += gpio-max7301.o
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obj-$(CONFIG_GPIO_MAX732X) += gpio-max732x.o
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obj-$(CONFIG_GPIO_MB86S7X) += gpio-mb86s7x.o
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obj-$(CONFIG_GPIO_MENZ127) += gpio-menz127.o
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obj-$(CONFIG_GPIO_MC33880) += gpio-mc33880.o
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obj-$(CONFIG_GPIO_MC9S08DZ60) += gpio-mc9s08dz60.o
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obj-$(CONFIG_GPIO_MCP23S08) += gpio-mcp23s08.o

‎drivers/gpio/gpio-menz127.c

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/*
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* MEN 16Z127 GPIO driver
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*
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* Copyright (C) 2016 MEN Mikroelektronik GmbH (www.men.de)
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the Free
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* Software Foundation; version 2 of the License.
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/io.h>
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#include <linux/err.h>
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#include <linux/mcb.h>
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#include <linux/bitops.h>
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#include <linux/gpio/driver.h>
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#define MEN_Z127_CTRL 0x00
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#define MEN_Z127_PSR 0x04
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#define MEN_Z127_IRQR 0x08
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#define MEN_Z127_GPIODR 0x0c
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#define MEN_Z127_IER1 0x10
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#define MEN_Z127_IER2 0x14
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#define MEN_Z127_DBER 0x18
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#define MEN_Z127_ODER 0x1C
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#define GPIO_TO_DBCNT_REG(gpio) ((gpio * 4) + 0x80)
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#define MEN_Z127_DB_MIN_US 50
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/* 16 bit compare register. Each bit represents 50us */
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#define MEN_Z127_DB_MAX_US (0xffff * MEN_Z127_DB_MIN_US)
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#define MEN_Z127_DB_IN_RANGE(db) ((db >= MEN_Z127_DB_MIN_US) && \
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(db <= MEN_Z127_DB_MAX_US))
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struct men_z127_gpio {
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struct gpio_chip gc;
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void __iomem *reg_base;
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struct mcb_device *mdev;
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struct resource *mem;
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spinlock_t lock;
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};
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static int men_z127_debounce(struct gpio_chip *gc, unsigned gpio,
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unsigned debounce)
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{
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struct men_z127_gpio *priv = gpiochip_get_data(gc);
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struct device *dev = &priv->mdev->dev;
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unsigned int rnd;
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u32 db_en, db_cnt;
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if (!MEN_Z127_DB_IN_RANGE(debounce)) {
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dev_err(dev, "debounce value %u out of range", debounce);
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return -EINVAL;
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}
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if (debounce > 0) {
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/* round up or down depending on MSB-1 */
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rnd = fls(debounce) - 1;
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if (rnd && (debounce & BIT(rnd - 1)))
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debounce = round_up(debounce, MEN_Z127_DB_MIN_US);
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else
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debounce = round_down(debounce, MEN_Z127_DB_MIN_US);
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if (debounce > MEN_Z127_DB_MAX_US)
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debounce = MEN_Z127_DB_MAX_US;
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/* 50us per register unit */
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debounce /= 50;
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}
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spin_lock(&priv->lock);
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db_en = readl(priv->reg_base + MEN_Z127_DBER);
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if (debounce == 0) {
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db_en &= ~BIT(gpio);
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db_cnt = 0;
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} else {
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db_en |= BIT(gpio);
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db_cnt = debounce;
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}
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writel(db_en, priv->reg_base + MEN_Z127_DBER);
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writel(db_cnt, priv->reg_base + GPIO_TO_DBCNT_REG(gpio));
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spin_unlock(&priv->lock);
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return 0;
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}
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static int men_z127_request(struct gpio_chip *gc, unsigned gpio_pin)
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{
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struct men_z127_gpio *priv = gpiochip_get_data(gc);
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u32 od_en;
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if (gpio_pin >= gc->ngpio)
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return -EINVAL;
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spin_lock(&priv->lock);
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od_en = readl(priv->reg_base + MEN_Z127_ODER);
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if (gpiochip_line_is_open_drain(gc, gpio_pin))
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od_en |= BIT(gpio_pin);
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else
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od_en &= ~BIT(gpio_pin);
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writel(od_en, priv->reg_base + MEN_Z127_ODER);
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spin_unlock(&priv->lock);
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return 0;
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}
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static int men_z127_probe(struct mcb_device *mdev,
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const struct mcb_device_id *id)
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{
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struct men_z127_gpio *men_z127_gpio;
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struct device *dev = &mdev->dev;
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int ret;
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men_z127_gpio = devm_kzalloc(dev, sizeof(struct men_z127_gpio),
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GFP_KERNEL);
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if (!men_z127_gpio)
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return -ENOMEM;
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men_z127_gpio->mem = mcb_request_mem(mdev, dev_name(dev));
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if (IS_ERR(men_z127_gpio->mem)) {
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dev_err(dev, "failed to request device memory");
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return PTR_ERR(men_z127_gpio->mem);
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}
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men_z127_gpio->reg_base = ioremap(men_z127_gpio->mem->start,
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resource_size(men_z127_gpio->mem));
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if (men_z127_gpio->reg_base == NULL) {
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ret = -ENXIO;
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goto err_release;
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}
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men_z127_gpio->mdev = mdev;
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mcb_set_drvdata(mdev, men_z127_gpio);
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ret = bgpio_init(&men_z127_gpio->gc, &mdev->dev, 4,
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men_z127_gpio->reg_base + MEN_Z127_PSR,
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men_z127_gpio->reg_base + MEN_Z127_CTRL,
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NULL,
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men_z127_gpio->reg_base + MEN_Z127_GPIODR,
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NULL, 0);
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if (ret)
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goto err_unmap;
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men_z127_gpio->gc.set_debounce = men_z127_debounce;
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men_z127_gpio->gc.request = men_z127_request;
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ret = gpiochip_add_data(&men_z127_gpio->gc, men_z127_gpio);
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if (ret) {
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dev_err(dev, "failed to register MEN 16Z127 GPIO controller");
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goto err_unmap;
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}
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dev_info(dev, "MEN 16Z127 GPIO driver registered");
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return 0;
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err_unmap:
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iounmap(men_z127_gpio->reg_base);
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err_release:
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mcb_release_mem(men_z127_gpio->mem);
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return ret;
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}
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static void men_z127_remove(struct mcb_device *mdev)
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{
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struct men_z127_gpio *men_z127_gpio = mcb_get_drvdata(mdev);
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gpiochip_remove(&men_z127_gpio->gc);
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iounmap(men_z127_gpio->reg_base);
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mcb_release_mem(men_z127_gpio->mem);
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}
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static const struct mcb_device_id men_z127_ids[] = {
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{ .device = 0x7f },
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{ }
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};
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MODULE_DEVICE_TABLE(mcb, men_z127_ids);
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static struct mcb_driver men_z127_driver = {
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.driver = {
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.name = "z127-gpio",
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.owner = THIS_MODULE,
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},
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.probe = men_z127_probe,
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.remove = men_z127_remove,
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.id_table = men_z127_ids,
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};
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module_mcb_driver(men_z127_driver);
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MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
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MODULE_DESCRIPTION("MEN 16z127 GPIO Controller");
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MODULE_LICENSE("GPL v2");
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MODULE_ALIAS("mcb:16z127");

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