diff options
Diffstat (limited to 'drivers/gpio/gpio-iop.c')
| -rw-r--r-- | drivers/gpio/gpio-iop.c | 132 | 
1 files changed, 132 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-iop.c b/drivers/gpio/gpio-iop.c new file mode 100644 index 00000000000..0a5e9d3f308 --- /dev/null +++ b/drivers/gpio/gpio-iop.c @@ -0,0 +1,132 @@ +/* + * arch/arm/plat-iop/gpio.c + * GPIO handling for Intel IOP3xx processors. + * + * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org> + * + * 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; either version 2 of the License, or (at + * your option) any later version. + */ + +#include <linux/device.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/gpio.h> +#include <linux/export.h> +#include <linux/platform_device.h> +#include <linux/bitops.h> +#include <linux/io.h> + +#define IOP3XX_N_GPIOS	8 + +#define GPIO_IN			0 +#define GPIO_OUT		1 +#define GPIO_LOW		0 +#define GPIO_HIGH		1 + +/* Memory base offset */ +static void __iomem *base; + +#define IOP3XX_GPIO_REG(reg)	(base + (reg)) +#define IOP3XX_GPOE		IOP3XX_GPIO_REG(0x0000) +#define IOP3XX_GPID		IOP3XX_GPIO_REG(0x0004) +#define IOP3XX_GPOD		IOP3XX_GPIO_REG(0x0008) + +static void gpio_line_config(int line, int direction) +{ +	unsigned long flags; +	u32 val; + +	local_irq_save(flags); +	val = readl(IOP3XX_GPOE); +	if (direction == GPIO_IN) { +		val |= BIT(line); +	} else if (direction == GPIO_OUT) { +		val &= ~BIT(line); +	} +	writel(val, IOP3XX_GPOE); +	local_irq_restore(flags); +} + +static int gpio_line_get(int line) +{ +	return !!(readl(IOP3XX_GPID) & BIT(line)); +} + +static void gpio_line_set(int line, int value) +{ +	unsigned long flags; +	u32 val; + +	local_irq_save(flags); +	val = readl(IOP3XX_GPOD); +	if (value == GPIO_LOW) { +		val &= ~BIT(line); +	} else if (value == GPIO_HIGH) { +		val |= BIT(line); +	} +	writel(val, IOP3XX_GPOD); +	local_irq_restore(flags); +} + +static int iop3xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) +{ +	gpio_line_config(gpio, GPIO_IN); +	return 0; +} + +static int iop3xx_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int level) +{ +	gpio_line_set(gpio, level); +	gpio_line_config(gpio, GPIO_OUT); +	return 0; +} + +static int iop3xx_gpio_get_value(struct gpio_chip *chip, unsigned gpio) +{ +	return gpio_line_get(gpio); +} + +static void iop3xx_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value) +{ +	gpio_line_set(gpio, value); +} + +static struct gpio_chip iop3xx_chip = { +	.label			= "iop3xx", +	.direction_input	= iop3xx_gpio_direction_input, +	.get			= iop3xx_gpio_get_value, +	.direction_output	= iop3xx_gpio_direction_output, +	.set			= iop3xx_gpio_set_value, +	.base			= 0, +	.ngpio			= IOP3XX_N_GPIOS, +}; + +static int iop3xx_gpio_probe(struct platform_device *pdev) +{ +	struct resource *res; + +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0); +	base = devm_ioremap_resource(&pdev->dev, res); +	if (IS_ERR(base)) +		return PTR_ERR(base); + +	return gpiochip_add(&iop3xx_chip); +} + +static struct platform_driver iop3xx_gpio_driver = { +	.driver = { +		.name = "gpio-iop", +		.owner = THIS_MODULE, +	}, +	.probe = iop3xx_gpio_probe, +}; + +static int __init iop3xx_gpio_init(void) +{ +	return platform_driver_register(&iop3xx_gpio_driver); +} +arch_initcall(iop3xx_gpio_init);  | 
