drivers/gpio/gpio-ftgpio010.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Faraday Technolog FTGPIO010 gpiochip and interrupt routines
  * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
  *
  * Based on arch/arm/mach-gemini/gpio.c:
  * Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
  *
  * Based on plat-mxc/gpio.c:
  * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
  * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
  */
 #include <linux/gpio/driver.h>
 #include <linux/io.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/bitops.h>
 #include <linux/clk.h>

 /* GPIO registers definition */
 #define GPIO_DATA_OUT		0x00
 #define GPIO_DATA_IN		0x04
 #define GPIO_DIR		0x08
 #define GPIO_BYPASS_IN		0x0C
 #define GPIO_DATA_SET		0x10
 #define GPIO_DATA_CLR		0x14
 #define GPIO_PULL_EN		0x18
 #define GPIO_PULL_TYPE		0x1C
 #define GPIO_INT_EN		0x20
 #define GPIO_INT_STAT_RAW	0x24
 #define GPIO_INT_STAT_MASKED	0x28
 #define GPIO_INT_MASK		0x2C
 #define GPIO_INT_CLR		0x30
 #define GPIO_INT_TYPE		0x34
 #define GPIO_INT_BOTH_EDGE	0x38
 #define GPIO_INT_LEVEL		0x3C
 #define GPIO_DEBOUNCE_EN	0x40
 #define GPIO_DEBOUNCE_PRESCALE	0x44

 /**
  * struct ftgpio_gpio - Gemini GPIO state container
  * @dev: containing device for this instance
  * @gc: gpiochip for this instance
  * @base: remapped I/O-memory base
  * @clk: silicon clock
  */
 struct ftgpio_gpio {
 	struct device *dev;
 	struct gpio_chip gc;
 	void __iomem *base;
 	struct clk *clk;
 };

 static void ftgpio_gpio_ack_irq(struct irq_data *d)
 {
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 	struct ftgpio_gpio *g = gpiochip_get_data(gc);

 	writel(BIT(irqd_to_hwirq(d)), g->base + GPIO_INT_CLR);
 }

 static void ftgpio_gpio_mask_irq(struct irq_data *d)
 {
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 	struct ftgpio_gpio *g = gpiochip_get_data(gc);
 	u32 val;

 	val = readl(g->base + GPIO_INT_EN);
 	val &= ~BIT(irqd_to_hwirq(d));
 	writel(val, g->base + GPIO_INT_EN);
 	gpiochip_disable_irq(gc, irqd_to_hwirq(d));
 }

 static void ftgpio_gpio_unmask_irq(struct irq_data *d)
 {
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 	struct ftgpio_gpio *g = gpiochip_get_data(gc);
 	u32 val;

 	gpiochip_enable_irq(gc, irqd_to_hwirq(d));
 	val = readl(g->base + GPIO_INT_EN);
 	val |= BIT(irqd_to_hwirq(d));
 	writel(val, g->base + GPIO_INT_EN);
 }

 static int ftgpio_gpio_set_irq_type(struct irq_data *d, unsigned int type)
 {
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 	struct ftgpio_gpio *g = gpiochip_get_data(gc);
 	u32 mask = BIT(irqd_to_hwirq(d));
 	u32 reg_both, reg_level, reg_type;

 	reg_type = readl(g->base + GPIO_INT_TYPE);
 	reg_level = readl(g->base + GPIO_INT_LEVEL);
 	reg_both = readl(g->base + GPIO_INT_BOTH_EDGE);

 	switch (type) {
 	case IRQ_TYPE_EDGE_BOTH:
 		irq_set_handler_locked(d, handle_edge_irq);
 		reg_type &= ~mask;
 		reg_both |= mask;
 		break;
 	case IRQ_TYPE_EDGE_RISING:
 		irq_set_handler_locked(d, handle_edge_irq);
 		reg_type &= ~mask;
 		reg_both &= ~mask;
 		reg_level &= ~mask;
 		break;
 	case IRQ_TYPE_EDGE_FALLING:
 		irq_set_handler_locked(d, handle_edge_irq);
 		reg_type &= ~mask;
 		reg_both &= ~mask;
 		reg_level |= mask;
 		break;
 	case IRQ_TYPE_LEVEL_HIGH:
 		irq_set_handler_locked(d, handle_level_irq);
 		reg_type |= mask;
 		reg_level &= ~mask;
 		break;
 	case IRQ_TYPE_LEVEL_LOW:
 		irq_set_handler_locked(d, handle_level_irq);
 		reg_type |= mask;
 		reg_level |= mask;
 		break;
 	default:
 		irq_set_handler_locked(d, handle_bad_irq);
 		return -EINVAL;
 	}

 	writel(reg_type, g->base + GPIO_INT_TYPE);
 	writel(reg_level, g->base + GPIO_INT_LEVEL);
 	writel(reg_both, g->base + GPIO_INT_BOTH_EDGE);

 	ftgpio_gpio_ack_irq(d);

 	return 0;
 }

 static void ftgpio_gpio_irq_handler(struct irq_desc *desc)
 {
 	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
 	struct ftgpio_gpio *g = gpiochip_get_data(gc);
 	struct irq_chip *irqchip = irq_desc_get_chip(desc);
 	int offset;
 	unsigned long stat;

 	chained_irq_enter(irqchip, desc);

 	stat = readl(g->base + GPIO_INT_STAT_RAW);
 	if (stat)
 		for_each_set_bit(offset, &stat, gc->ngpio)
 			generic_handle_domain_irq(gc->irq.domain, offset);

 	chained_irq_exit(irqchip, desc);
 }

 static int ftgpio_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
 				  unsigned long config)
 {
 	enum pin_config_param param = pinconf_to_config_param(config);
 	u32 arg = pinconf_to_config_argument(config);
 	struct ftgpio_gpio *g = gpiochip_get_data(gc);
 	unsigned long pclk_freq;
 	u32 deb_div;
 	u32 val;

 	if (param != PIN_CONFIG_INPUT_DEBOUNCE)
 		return -ENOTSUPP;

 	/*
 	 * Debounce only works if interrupts are enabled. The manual
 	 * states that if PCLK is 66 MHz, and this is set to 0x7D0, then
 	 * PCLK is divided down to 33 kHz for the debounce timer. 0x7D0 is
 	 * 2000 decimal, so what they mean is simply that the PCLK is
 	 * divided by this value.
 	 *
 	 * As we get a debounce setting in microseconds, we calculate the
 	 * desired period time and see if we can get a suitable debounce
 	 * time.
 	 */
 	pclk_freq = clk_get_rate(g->clk);
 	deb_div = DIV_ROUND_CLOSEST(pclk_freq, arg);

 	/* This register is only 24 bits wide */
 	if (deb_div > (1 << 24))
 		return -ENOTSUPP;

 	dev_dbg(g->dev, "prescale divisor: %08x, resulting frequency %lu Hz\n",
 		deb_div, (pclk_freq/deb_div));

 	val = readl(g->base + GPIO_DEBOUNCE_PRESCALE);
 	if (val == deb_div) {
 		/*
 		 * The debounce timer happens to already be set to the
 		 * desirable value, what a coincidence! We can just enable
 		 * debounce on this GPIO line and return. This happens more
 		 * often than you think, for example when all GPIO keys
 		 * on a system are requesting the same debounce interval.
 		 */
 		val = readl(g->base + GPIO_DEBOUNCE_EN);
 		val |= BIT(offset);
 		writel(val, g->base + GPIO_DEBOUNCE_EN);
 		return 0;
 	}

 	val = readl(g->base + GPIO_DEBOUNCE_EN);
 	if (val) {
 		/*
 		 * Oh no! Someone is already using the debounce with
 		 * another setting than what we need. Bummer.
 		 */
 		return -ENOTSUPP;
 	}

 	/* First come, first serve */
 	writel(deb_div, g->base + GPIO_DEBOUNCE_PRESCALE);
 	/* Enable debounce */
 	val |= BIT(offset);
 	writel(val, g->base + GPIO_DEBOUNCE_EN);

 	return 0;
 }

 static const struct irq_chip ftgpio_irq_chip = {
 	.name = "FTGPIO010",
 	.irq_ack = ftgpio_gpio_ack_irq,
 	.irq_mask = ftgpio_gpio_mask_irq,
 	.irq_unmask = ftgpio_gpio_unmask_irq,
 	.irq_set_type = ftgpio_gpio_set_irq_type,
 	.flags = IRQCHIP_IMMUTABLE,
 	 GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };

 static int ftgpio_gpio_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct ftgpio_gpio *g;
 	struct gpio_irq_chip *girq;
 	int irq;
 	int ret;

 	g = devm_kzalloc(dev, sizeof(*g), GFP_KERNEL);
 	if (!g)
 		return -ENOMEM;

 	g->dev = dev;

 	g->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(g->base))
 		return PTR_ERR(g->base);

 	irq = platform_get_irq(pdev, 0);
 	if (irq <= 0)
 		return irq ? irq : -EINVAL;

 	g->clk = devm_clk_get(dev, NULL);
 	if (!IS_ERR(g->clk)) {
 		ret = clk_prepare_enable(g->clk);
 		if (ret)
 			return ret;
 	} else if (PTR_ERR(g->clk) == -EPROBE_DEFER) {
 		/*
 		 * Percolate deferrals, for anything else,
 		 * just live without the clocking.
 		 */
 		return PTR_ERR(g->clk);
 	}

 	ret = bgpio_init(&g->gc, dev, 4,
 			 g->base + GPIO_DATA_IN,
 			 g->base + GPIO_DATA_SET,
 			 g->base + GPIO_DATA_CLR,
 			 g->base + GPIO_DIR,
 			 NULL,
 			 0);
 	if (ret) {
 		dev_err(dev, "unable to init generic GPIO\n");
 		goto dis_clk;
 	}
 	g->gc.label = "FTGPIO010";
 	g->gc.base = -1;
 	g->gc.parent = dev;
 	g->gc.owner = THIS_MODULE;
 	/* ngpio is set by bgpio_init() */

 	/* We need a silicon clock to do debounce */
 	if (!IS_ERR(g->clk))
 		g->gc.set_config = ftgpio_gpio_set_config;

 	girq = &g->gc.irq;
 	gpio_irq_chip_set_chip(girq, &ftgpio_irq_chip);
 	girq->parent_handler = ftgpio_gpio_irq_handler;
 	girq->num_parents = 1;
 	girq->parents = devm_kcalloc(dev, 1, sizeof(*girq->parents),
 				     GFP_KERNEL);
 	if (!girq->parents) {
 		ret = -ENOMEM;
 		goto dis_clk;
 	}
 	girq->default_type = IRQ_TYPE_NONE;
 	girq->handler = handle_bad_irq;
 	girq->parents[0] = irq;

 	/* Disable, unmask and clear all interrupts */
 	writel(0x0, g->base + GPIO_INT_EN);
 	writel(0x0, g->base + GPIO_INT_MASK);
 	writel(~0x0, g->base + GPIO_INT_CLR);

 	/* Clear any use of debounce */
 	writel(0x0, g->base + GPIO_DEBOUNCE_EN);

 	ret = devm_gpiochip_add_data(dev, &g->gc, g);
 	if (ret)
 		goto dis_clk;

 	platform_set_drvdata(pdev, g);
 	dev_info(dev, "FTGPIO010 @%p registered\n", g->base);

 	return 0;

 dis_clk:
 	clk_disable_unprepare(g->clk);

 	return ret;
 }

 static int ftgpio_gpio_remove(struct platform_device *pdev)
 {
 	struct ftgpio_gpio *g = platform_get_drvdata(pdev);

 	clk_disable_unprepare(g->clk);

 	return 0;
 }

 static const struct of_device_id ftgpio_gpio_of_match[] = {
 	{
 		.compatible = "cortina,gemini-gpio",
 	},
 	{
 		.compatible = "moxa,moxart-gpio",
 	},
 	{
 		.compatible = "faraday,ftgpio010",
 	},
 	{},
 };

 static struct platform_driver ftgpio_gpio_driver = {
 	.driver = {
 		.name		= "ftgpio010-gpio",
 		.of_match_table = of_match_ptr(ftgpio_gpio_of_match),
 	},
 	.probe = ftgpio_gpio_probe,
 	.remove = ftgpio_gpio_remove,
 };
 builtin_platform_driver(ftgpio_gpio_driver);
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Faraday Technolog FTGPIO010 gpiochip and interrupt routines
	* Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
	*
	* Based on arch/arm/mach-gemini/gpio.c:
	* Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
	*
	* Based on plat-mxc/gpio.c:
	* MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
	* Copyright 2008 Juergen Beisert, kernel@pengutronix.de
	*/
	#include <linux/gpio/driver.h>
	#include <linux/io.h>
	#include <linux/interrupt.h>
	#include <linux/platform_device.h>
	#include <linux/bitops.h>
	#include <linux/clk.h>

	/* GPIO registers definition */
	#define GPIO_DATA_OUT 0x00
	#define GPIO_DATA_IN 0x04
	#define GPIO_DIR 0x08
	#define GPIO_BYPASS_IN 0x0C
	#define GPIO_DATA_SET 0x10
	#define GPIO_DATA_CLR 0x14
	#define GPIO_PULL_EN 0x18
	#define GPIO_PULL_TYPE 0x1C
	#define GPIO_INT_EN 0x20
	#define GPIO_INT_STAT_RAW 0x24
	#define GPIO_INT_STAT_MASKED 0x28
	#define GPIO_INT_MASK 0x2C
	#define GPIO_INT_CLR 0x30
	#define GPIO_INT_TYPE 0x34
	#define GPIO_INT_BOTH_EDGE 0x38
	#define GPIO_INT_LEVEL 0x3C
	#define GPIO_DEBOUNCE_EN 0x40
	#define GPIO_DEBOUNCE_PRESCALE 0x44

	/**
	* struct ftgpio_gpio - Gemini GPIO state container
	* @dev: containing device for this instance
	* @gc: gpiochip for this instance
	* @base: remapped I/O-memory base
	* @clk: silicon clock
	*/
	struct ftgpio_gpio {
	struct device *dev;
	struct gpio_chip gc;
	void __iomem *base;
	struct clk *clk;
	};

	static void ftgpio_gpio_ack_irq(struct irq_data *d)
	{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct ftgpio_gpio *g = gpiochip_get_data(gc);

	writel(BIT(irqd_to_hwirq(d)), g->base + GPIO_INT_CLR);
	}

	static void ftgpio_gpio_mask_irq(struct irq_data *d)
	{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct ftgpio_gpio *g = gpiochip_get_data(gc);
	u32 val;

	val = readl(g->base + GPIO_INT_EN);
	val &= ~BIT(irqd_to_hwirq(d));
	writel(val, g->base + GPIO_INT_EN);
	gpiochip_disable_irq(gc, irqd_to_hwirq(d));
	}

	static void ftgpio_gpio_unmask_irq(struct irq_data *d)
	{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct ftgpio_gpio *g = gpiochip_get_data(gc);
	u32 val;

	gpiochip_enable_irq(gc, irqd_to_hwirq(d));
	val = readl(g->base + GPIO_INT_EN);
	val \|= BIT(irqd_to_hwirq(d));
	writel(val, g->base + GPIO_INT_EN);
	}

	static int ftgpio_gpio_set_irq_type(struct irq_data *d, unsigned int type)
	{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct ftgpio_gpio *g = gpiochip_get_data(gc);
	u32 mask = BIT(irqd_to_hwirq(d));
	u32 reg_both, reg_level, reg_type;

	reg_type = readl(g->base + GPIO_INT_TYPE);
	reg_level = readl(g->base + GPIO_INT_LEVEL);
	reg_both = readl(g->base + GPIO_INT_BOTH_EDGE);

	switch (type) {
	case IRQ_TYPE_EDGE_BOTH:
	irq_set_handler_locked(d, handle_edge_irq);
	reg_type &= ~mask;
	reg_both \|= mask;
	break;
	case IRQ_TYPE_EDGE_RISING:
	irq_set_handler_locked(d, handle_edge_irq);
	reg_type &= ~mask;
	reg_both &= ~mask;
	reg_level &= ~mask;
	break;
	case IRQ_TYPE_EDGE_FALLING:
	irq_set_handler_locked(d, handle_edge_irq);
	reg_type &= ~mask;
	reg_both &= ~mask;
	reg_level \|= mask;
	break;
	case IRQ_TYPE_LEVEL_HIGH:
	irq_set_handler_locked(d, handle_level_irq);
	reg_type \|= mask;
	reg_level &= ~mask;
	break;
	case IRQ_TYPE_LEVEL_LOW:
	irq_set_handler_locked(d, handle_level_irq);
	reg_type \|= mask;
	reg_level \|= mask;
	break;
	default:
	irq_set_handler_locked(d, handle_bad_irq);
	return -EINVAL;
	}

	writel(reg_type, g->base + GPIO_INT_TYPE);
	writel(reg_level, g->base + GPIO_INT_LEVEL);
	writel(reg_both, g->base + GPIO_INT_BOTH_EDGE);

	ftgpio_gpio_ack_irq(d);

	return 0;
	}

	static void ftgpio_gpio_irq_handler(struct irq_desc *desc)
	{
	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
	struct ftgpio_gpio *g = gpiochip_get_data(gc);
	struct irq_chip *irqchip = irq_desc_get_chip(desc);
	int offset;
	unsigned long stat;

	chained_irq_enter(irqchip, desc);

	stat = readl(g->base + GPIO_INT_STAT_RAW);
	if (stat)
	for_each_set_bit(offset, &stat, gc->ngpio)
	generic_handle_domain_irq(gc->irq.domain, offset);

	chained_irq_exit(irqchip, desc);
	}

	static int ftgpio_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
	unsigned long config)
	{
	enum pin_config_param param = pinconf_to_config_param(config);
	u32 arg = pinconf_to_config_argument(config);
	struct ftgpio_gpio *g = gpiochip_get_data(gc);
	unsigned long pclk_freq;
	u32 deb_div;
	u32 val;

	if (param != PIN_CONFIG_INPUT_DEBOUNCE)
	return -ENOTSUPP;

	/*
	* Debounce only works if interrupts are enabled. The manual
	* states that if PCLK is 66 MHz, and this is set to 0x7D0, then
	* PCLK is divided down to 33 kHz for the debounce timer. 0x7D0 is
	* 2000 decimal, so what they mean is simply that the PCLK is
	* divided by this value.
	*
	* As we get a debounce setting in microseconds, we calculate the
	* desired period time and see if we can get a suitable debounce
	* time.
	*/
	pclk_freq = clk_get_rate(g->clk);
	deb_div = DIV_ROUND_CLOSEST(pclk_freq, arg);

	/* This register is only 24 bits wide */
	if (deb_div > (1 << 24))
	return -ENOTSUPP;

	dev_dbg(g->dev, "prescale divisor: %08x, resulting frequency %lu Hz\n",
	deb_div, (pclk_freq/deb_div));

	val = readl(g->base + GPIO_DEBOUNCE_PRESCALE);
	if (val == deb_div) {
	/*
	* The debounce timer happens to already be set to the
	* desirable value, what a coincidence! We can just enable
	* debounce on this GPIO line and return. This happens more
	* often than you think, for example when all GPIO keys
	* on a system are requesting the same debounce interval.
	*/
	val = readl(g->base + GPIO_DEBOUNCE_EN);
	val \|= BIT(offset);
	writel(val, g->base + GPIO_DEBOUNCE_EN);
	return 0;
	}

	val = readl(g->base + GPIO_DEBOUNCE_EN);
	if (val) {
	/*
	* Oh no! Someone is already using the debounce with
	* another setting than what we need. Bummer.
	*/
	return -ENOTSUPP;
	}

	/* First come, first serve */
	writel(deb_div, g->base + GPIO_DEBOUNCE_PRESCALE);
	/* Enable debounce */
	val \|= BIT(offset);
	writel(val, g->base + GPIO_DEBOUNCE_EN);

	return 0;
	}

	static const struct irq_chip ftgpio_irq_chip = {
	.name = "FTGPIO010",
	.irq_ack = ftgpio_gpio_ack_irq,
	.irq_mask = ftgpio_gpio_mask_irq,
	.irq_unmask = ftgpio_gpio_unmask_irq,
	.irq_set_type = ftgpio_gpio_set_irq_type,
	.flags = IRQCHIP_IMMUTABLE,
	GPIOCHIP_IRQ_RESOURCE_HELPERS,
	};

	static int ftgpio_gpio_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct ftgpio_gpio *g;
	struct gpio_irq_chip *girq;
	int irq;
	int ret;

	g = devm_kzalloc(dev, sizeof(*g), GFP_KERNEL);
	if (!g)
	return -ENOMEM;

	g->dev = dev;

	g->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(g->base))
	return PTR_ERR(g->base);

	irq = platform_get_irq(pdev, 0);
	if (irq <= 0)
	return irq ? irq : -EINVAL;

	g->clk = devm_clk_get(dev, NULL);
	if (!IS_ERR(g->clk)) {
	ret = clk_prepare_enable(g->clk);
	if (ret)
	return ret;
	} else if (PTR_ERR(g->clk) == -EPROBE_DEFER) {
	/*
	* Percolate deferrals, for anything else,
	* just live without the clocking.
	*/
	return PTR_ERR(g->clk);
	}

	ret = bgpio_init(&g->gc, dev, 4,
	g->base + GPIO_DATA_IN,
	g->base + GPIO_DATA_SET,
	g->base + GPIO_DATA_CLR,
	g->base + GPIO_DIR,
	NULL,
	0);
	if (ret) {
	dev_err(dev, "unable to init generic GPIO\n");
	goto dis_clk;
	}
	g->gc.label = "FTGPIO010";
	g->gc.base = -1;
	g->gc.parent = dev;
	g->gc.owner = THIS_MODULE;
	/* ngpio is set by bgpio_init() */

	/* We need a silicon clock to do debounce */
	if (!IS_ERR(g->clk))
	g->gc.set_config = ftgpio_gpio_set_config;

	girq = &g->gc.irq;
	gpio_irq_chip_set_chip(girq, &ftgpio_irq_chip);
	girq->parent_handler = ftgpio_gpio_irq_handler;
	girq->num_parents = 1;
	girq->parents = devm_kcalloc(dev, 1, sizeof(*girq->parents),
	GFP_KERNEL);
	if (!girq->parents) {
	ret = -ENOMEM;
	goto dis_clk;
	}
	girq->default_type = IRQ_TYPE_NONE;
	girq->handler = handle_bad_irq;
	girq->parents[0] = irq;

	/* Disable, unmask and clear all interrupts */
	writel(0x0, g->base + GPIO_INT_EN);
	writel(0x0, g->base + GPIO_INT_MASK);
	writel(~0x0, g->base + GPIO_INT_CLR);

	/* Clear any use of debounce */
	writel(0x0, g->base + GPIO_DEBOUNCE_EN);

	ret = devm_gpiochip_add_data(dev, &g->gc, g);
	if (ret)
	goto dis_clk;

	platform_set_drvdata(pdev, g);
	dev_info(dev, "FTGPIO010 @%p registered\n", g->base);

	return 0;

	dis_clk:
	clk_disable_unprepare(g->clk);

	return ret;
	}

	static int ftgpio_gpio_remove(struct platform_device *pdev)
	{
	struct ftgpio_gpio *g = platform_get_drvdata(pdev);

	clk_disable_unprepare(g->clk);

	return 0;
	}

	static const struct of_device_id ftgpio_gpio_of_match[] = {
	{
	.compatible = "cortina,gemini-gpio",
	},
	{
	.compatible = "moxa,moxart-gpio",
	},
	{
	.compatible = "faraday,ftgpio010",
	},
	{},
	};

	static struct platform_driver ftgpio_gpio_driver = {
	.driver = {
	.name = "ftgpio010-gpio",
	.of_match_table = of_match_ptr(ftgpio_gpio_of_match),
	},
	.probe = ftgpio_gpio_probe,
	.remove = ftgpio_gpio_remove,
	};
	builtin_platform_driver(ftgpio_gpio_driver);