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Diffstat (limited to 'arch/mips/kernel/gpio_txx9.c')
-rw-r--r--arch/mips/kernel/gpio_txx9.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/arch/mips/kernel/gpio_txx9.c b/arch/mips/kernel/gpio_txx9.c
new file mode 100644
index 000000000..c6854d9df
--- /dev/null
+++ b/arch/mips/kernel/gpio_txx9.c
@@ -0,0 +1,89 @@
+/*
+ * 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);
+}