diff options
Diffstat (limited to 'arch/mips/kernel/gpio_txx9.c')
-rw-r--r-- | arch/mips/kernel/gpio_txx9.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/arch/mips/kernel/gpio_txx9.c b/arch/mips/kernel/gpio_txx9.c new file mode 100644 index 000000000000..b1436a857998 --- /dev/null +++ b/arch/mips/kernel/gpio_txx9.c @@ -0,0 +1,87 @@ +/* + * A gpio chip driver for TXx9 SoCs + * + * Copyright (C) 2008 Atsushi Nemoto <anemo@mba.ocn.ne.jp> + * + * 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/init.h> +#include <linux/spinlock.h> +#include <linux/gpio.h> +#include <linux/errno.h> +#include <linux/io.h> +#include <asm/txx9pio.h> + +static DEFINE_SPINLOCK(txx9_gpio_lock); + +static struct txx9_pio_reg __iomem *txx9_pioptr; + +static int txx9_gpio_get(struct gpio_chip *chip, unsigned int offset) +{ + return __raw_readl(&txx9_pioptr->din) & (1 << offset); +} + +static void txx9_gpio_set_raw(unsigned int offset, int value) +{ + u32 val; + val = __raw_readl(&txx9_pioptr->dout); + if (value) + val |= 1 << offset; + else + val &= ~(1 << offset); + __raw_writel(val, &txx9_pioptr->dout); +} + +static void txx9_gpio_set(struct gpio_chip *chip, unsigned int offset, + int value) +{ + unsigned long flags; + spin_lock_irqsave(&txx9_gpio_lock, flags); + txx9_gpio_set_raw(offset, value); + mmiowb(); + spin_unlock_irqrestore(&txx9_gpio_lock, flags); +} + +static int txx9_gpio_dir_in(struct gpio_chip *chip, unsigned int offset) +{ + spin_lock_irq(&txx9_gpio_lock); + __raw_writel(__raw_readl(&txx9_pioptr->dir) & ~(1 << offset), + &txx9_pioptr->dir); + mmiowb(); + spin_unlock_irq(&txx9_gpio_lock); + return 0; +} + +static int txx9_gpio_dir_out(struct gpio_chip *chip, unsigned int offset, + int value) +{ + spin_lock_irq(&txx9_gpio_lock); + txx9_gpio_set_raw(offset, value); + __raw_writel(__raw_readl(&txx9_pioptr->dir) | (1 << offset), + &txx9_pioptr->dir); + mmiowb(); + spin_unlock_irq(&txx9_gpio_lock); + return 0; +} + +static struct gpio_chip txx9_gpio_chip = { + .get = txx9_gpio_get, + .set = txx9_gpio_set, + .direction_input = txx9_gpio_dir_in, + .direction_output = txx9_gpio_dir_out, + .label = "TXx9", +}; + +int __init txx9_gpio_init(unsigned long baseaddr, + unsigned int base, unsigned int num) +{ + txx9_pioptr = ioremap(baseaddr, sizeof(struct txx9_pio_reg)); + if (!txx9_pioptr) + return -ENODEV; + txx9_gpio_chip.base = base; + txx9_gpio_chip.ngpio = num; + return gpiochip_add(&txx9_gpio_chip); +} |