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	It's hard for occasional GPIO code reader/writer to know if values 0/1 equal to IN or OUT. Use defined GPIO_LINE_DIRECTION_IN and GPIO_LINE_DIRECTION_OUT to help them out. NOTE - for gpio-amd-fch and gpio-bd9571mwv: This commit also changes the return value for direction get to equal 1 for direction INPUT. Prior this commit these drivers might have returned some other positive value but 1 for INPUT. Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com> Acked-by: Scott Branden <scott.branden@broadcom.com> Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com> Reviewed-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
		
			
				
	
	
		
			149 lines
		
	
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			149 lines
		
	
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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 * 74xx MMIO GPIO driver
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 *
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 *  Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
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 */
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#include <linux/err.h>
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#include <linux/module.h>
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#include <linux/of_device.h>
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#include <linux/gpio/driver.h>
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#include <linux/platform_device.h>
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#define MMIO_74XX_DIR_IN	(0 << 8)
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#define MMIO_74XX_DIR_OUT	(1 << 8)
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#define MMIO_74XX_BIT_CNT(x)	((x) & 0xff)
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struct mmio_74xx_gpio_priv {
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	struct gpio_chip	gc;
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	unsigned		flags;
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};
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static const struct of_device_id mmio_74xx_gpio_ids[] = {
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	{
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		.compatible	= "ti,741g125",
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		.data		= (const void *)(MMIO_74XX_DIR_IN | 1),
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	},
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	{
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		.compatible	= "ti,742g125",
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		.data		= (const void *)(MMIO_74XX_DIR_IN | 2),
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	},
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	{
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		.compatible	= "ti,74125",
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		.data		= (const void *)(MMIO_74XX_DIR_IN | 4),
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	},
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	{
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		.compatible	= "ti,74365",
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		.data		= (const void *)(MMIO_74XX_DIR_IN | 6),
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	},
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	{
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		.compatible	= "ti,74244",
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		.data		= (const void *)(MMIO_74XX_DIR_IN | 8),
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	},
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	{
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		.compatible	= "ti,741624",
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		.data		= (const void *)(MMIO_74XX_DIR_IN | 16),
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	},
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	{
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		.compatible	= "ti,741g74",
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		.data		= (const void *)(MMIO_74XX_DIR_OUT | 1),
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	},
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	{
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		.compatible	= "ti,7474",
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		.data		= (const void *)(MMIO_74XX_DIR_OUT | 2),
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	},
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	{
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		.compatible	= "ti,74175",
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		.data		= (const void *)(MMIO_74XX_DIR_OUT | 4),
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	},
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	{
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		.compatible	= "ti,74174",
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		.data		= (const void *)(MMIO_74XX_DIR_OUT | 6),
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	},
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	{
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		.compatible	= "ti,74273",
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		.data		= (const void *)(MMIO_74XX_DIR_OUT | 8),
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	},
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	{
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		.compatible	= "ti,7416374",
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		.data		= (const void *)(MMIO_74XX_DIR_OUT | 16),
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	},
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	{ }
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};
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MODULE_DEVICE_TABLE(of, mmio_74xx_gpio_ids);
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static int mmio_74xx_get_direction(struct gpio_chip *gc, unsigned offset)
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{
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	struct mmio_74xx_gpio_priv *priv = gpiochip_get_data(gc);
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	if (priv->flags & MMIO_74XX_DIR_OUT)
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		return GPIO_LINE_DIRECTION_OUT;
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	return  GPIO_LINE_DIRECTION_IN;
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}
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static int mmio_74xx_dir_in(struct gpio_chip *gc, unsigned int gpio)
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{
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	struct mmio_74xx_gpio_priv *priv = gpiochip_get_data(gc);
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	return (priv->flags & MMIO_74XX_DIR_OUT) ? -ENOTSUPP : 0;
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}
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static int mmio_74xx_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
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{
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	struct mmio_74xx_gpio_priv *priv = gpiochip_get_data(gc);
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	if (priv->flags & MMIO_74XX_DIR_OUT) {
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		gc->set(gc, gpio, val);
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		return 0;
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	}
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	return -ENOTSUPP;
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}
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static int mmio_74xx_gpio_probe(struct platform_device *pdev)
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{
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	struct mmio_74xx_gpio_priv *priv;
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	void __iomem *dat;
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	int err;
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	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
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	if (!priv)
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		return -ENOMEM;
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	priv->flags = (uintptr_t)of_device_get_match_data(&pdev->dev);
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	dat = devm_platform_ioremap_resource(pdev, 0);
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	if (IS_ERR(dat))
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		return PTR_ERR(dat);
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	err = bgpio_init(&priv->gc, &pdev->dev,
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			 DIV_ROUND_UP(MMIO_74XX_BIT_CNT(priv->flags), 8),
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			 dat, NULL, NULL, NULL, NULL, 0);
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	if (err)
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		return err;
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	priv->gc.direction_input = mmio_74xx_dir_in;
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	priv->gc.direction_output = mmio_74xx_dir_out;
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	priv->gc.get_direction = mmio_74xx_get_direction;
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	priv->gc.ngpio = MMIO_74XX_BIT_CNT(priv->flags);
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	priv->gc.owner = THIS_MODULE;
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	platform_set_drvdata(pdev, priv);
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	return devm_gpiochip_add_data(&pdev->dev, &priv->gc, priv);
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}
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static struct platform_driver mmio_74xx_gpio_driver = {
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	.driver	= {
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		.name		= "74xx-mmio-gpio",
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		.of_match_table	= mmio_74xx_gpio_ids,
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	},
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	.probe	= mmio_74xx_gpio_probe,
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};
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module_platform_driver(mmio_74xx_gpio_driver);
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
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MODULE_DESCRIPTION("74xx MMIO GPIO driver");
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