diff options
Diffstat (limited to 'drivers/gpio/gpio-iop.c')
-rw-r--r-- | drivers/gpio/gpio-iop.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-iop.c b/drivers/gpio/gpio-iop.c new file mode 100644 index 000000000000..c22a61be3a9c --- /dev/null +++ b/drivers/gpio/gpio-iop.c @@ -0,0 +1,130 @@ +/* + * 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); + + 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); |