/* * 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) { unsigned long flags; spin_lock_irqsave(&txx9_gpio_lock, flags); __raw_writel(__raw_readl(&txx9_pioptr->dir) & ~(1 << offset), &txx9_pioptr->dir); mmiowb(); spin_unlock_irqrestore(&txx9_gpio_lock, flags); return 0; } static int txx9_gpio_dir_out(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); __raw_writel(__raw_readl(&txx9_pioptr->dir) | (1 << offset), &txx9_pioptr->dir); mmiowb(); spin_unlock_irqrestore(&txx9_gpio_lock, flags); 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); }