diff options
Diffstat (limited to 'kernel/arch/arm/mach-w90x900/gpio.c')
-rw-r--r-- | kernel/arch/arm/mach-w90x900/gpio.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-w90x900/gpio.c b/kernel/arch/arm/mach-w90x900/gpio.c new file mode 100644 index 000000000..ba05aec7e --- /dev/null +++ b/kernel/arch/arm/mach-w90x900/gpio.c @@ -0,0 +1,154 @@ +/* + * linux/arch/arm/mach-w90x900/gpio.c + * + * Generic nuc900 GPIO handling + * + * Wan ZongShun <mcuos.com@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/clk.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/gpio.h> + +#include <mach/hardware.h> + +#define GPIO_BASE (W90X900_VA_GPIO) +#define GPIO_DIR (0x04) +#define GPIO_OUT (0x08) +#define GPIO_IN (0x0C) +#define GROUPINERV (0x10) +#define GPIO_GPIO(Nb) (0x00000001 << (Nb)) +#define to_nuc900_gpio_chip(c) container_of(c, struct nuc900_gpio_chip, chip) + +#define NUC900_GPIO_CHIP(name, base_gpio, nr_gpio) \ + { \ + .chip = { \ + .label = name, \ + .direction_input = nuc900_dir_input, \ + .direction_output = nuc900_dir_output, \ + .get = nuc900_gpio_get, \ + .set = nuc900_gpio_set, \ + .base = base_gpio, \ + .ngpio = nr_gpio, \ + } \ + } + +struct nuc900_gpio_chip { + struct gpio_chip chip; + void __iomem *regbase; /* Base of group register*/ + spinlock_t gpio_lock; +}; + +static int nuc900_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + struct nuc900_gpio_chip *nuc900_gpio = to_nuc900_gpio_chip(chip); + void __iomem *pio = nuc900_gpio->regbase + GPIO_IN; + unsigned int regval; + + regval = __raw_readl(pio); + regval &= GPIO_GPIO(offset); + + return (regval != 0); +} + +static void nuc900_gpio_set(struct gpio_chip *chip, unsigned offset, int val) +{ + struct nuc900_gpio_chip *nuc900_gpio = to_nuc900_gpio_chip(chip); + void __iomem *pio = nuc900_gpio->regbase + GPIO_OUT; + unsigned int regval; + unsigned long flags; + + spin_lock_irqsave(&nuc900_gpio->gpio_lock, flags); + + regval = __raw_readl(pio); + + if (val) + regval |= GPIO_GPIO(offset); + else + regval &= ~GPIO_GPIO(offset); + + __raw_writel(regval, pio); + + spin_unlock_irqrestore(&nuc900_gpio->gpio_lock, flags); +} + +static int nuc900_dir_input(struct gpio_chip *chip, unsigned offset) +{ + struct nuc900_gpio_chip *nuc900_gpio = to_nuc900_gpio_chip(chip); + void __iomem *pio = nuc900_gpio->regbase + GPIO_DIR; + unsigned int regval; + unsigned long flags; + + spin_lock_irqsave(&nuc900_gpio->gpio_lock, flags); + + regval = __raw_readl(pio); + regval &= ~GPIO_GPIO(offset); + __raw_writel(regval, pio); + + spin_unlock_irqrestore(&nuc900_gpio->gpio_lock, flags); + + return 0; +} + +static int nuc900_dir_output(struct gpio_chip *chip, unsigned offset, int val) +{ + struct nuc900_gpio_chip *nuc900_gpio = to_nuc900_gpio_chip(chip); + void __iomem *outreg = nuc900_gpio->regbase + GPIO_OUT; + void __iomem *pio = nuc900_gpio->regbase + GPIO_DIR; + unsigned int regval; + unsigned long flags; + + spin_lock_irqsave(&nuc900_gpio->gpio_lock, flags); + + regval = __raw_readl(pio); + regval |= GPIO_GPIO(offset); + __raw_writel(regval, pio); + + regval = __raw_readl(outreg); + + if (val) + regval |= GPIO_GPIO(offset); + else + regval &= ~GPIO_GPIO(offset); + + __raw_writel(regval, outreg); + + spin_unlock_irqrestore(&nuc900_gpio->gpio_lock, flags); + + return 0; +} + +static struct nuc900_gpio_chip nuc900_gpio[] = { + NUC900_GPIO_CHIP("GROUPC", 0, 16), + NUC900_GPIO_CHIP("GROUPD", 16, 10), + NUC900_GPIO_CHIP("GROUPE", 26, 14), + NUC900_GPIO_CHIP("GROUPF", 40, 10), + NUC900_GPIO_CHIP("GROUPG", 50, 17), + NUC900_GPIO_CHIP("GROUPH", 67, 8), + NUC900_GPIO_CHIP("GROUPI", 75, 17), +}; + +void __init nuc900_init_gpio(int nr_group) +{ + unsigned i; + struct nuc900_gpio_chip *gpio_chip; + + for (i = 0; i < nr_group; i++) { + gpio_chip = &nuc900_gpio[i]; + spin_lock_init(&gpio_chip->gpio_lock); + gpio_chip->regbase = GPIO_BASE + i * GROUPINERV; + gpiochip_add(&gpio_chip->chip); + } +} |