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-rw-r--r--arch/mips/kernel/gpio_txx9.c87
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 @@
1/*
2 * A gpio chip driver for TXx9 SoCs
3 *
4 * Copyright (C) 2008 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/init.h>
12#include <linux/spinlock.h>
13#include <linux/gpio.h>
14#include <linux/errno.h>
15#include <linux/io.h>
16#include <asm/txx9pio.h>
17
18static DEFINE_SPINLOCK(txx9_gpio_lock);
19
20static struct txx9_pio_reg __iomem *txx9_pioptr;
21
22static int txx9_gpio_get(struct gpio_chip *chip, unsigned int offset)
23{
24 return __raw_readl(&txx9_pioptr->din) & (1 << offset);
25}
26
27static void txx9_gpio_set_raw(unsigned int offset, int value)
28{
29 u32 val;
30 val = __raw_readl(&txx9_pioptr->dout);
31 if (value)
32 val |= 1 << offset;
33 else
34 val &= ~(1 << offset);
35 __raw_writel(val, &txx9_pioptr->dout);
36}
37
38static void txx9_gpio_set(struct gpio_chip *chip, unsigned int offset,
39 int value)
40{
41 unsigned long flags;
42 spin_lock_irqsave(&txx9_gpio_lock, flags);
43 txx9_gpio_set_raw(offset, value);
44 mmiowb();
45 spin_unlock_irqrestore(&txx9_gpio_lock, flags);
46}
47
48static int txx9_gpio_dir_in(struct gpio_chip *chip, unsigned int offset)
49{
50 spin_lock_irq(&txx9_gpio_lock);
51 __raw_writel(__raw_readl(&txx9_pioptr->dir) & ~(1 << offset),
52 &txx9_pioptr->dir);
53 mmiowb();
54 spin_unlock_irq(&txx9_gpio_lock);
55 return 0;
56}
57
58static int txx9_gpio_dir_out(struct gpio_chip *chip, unsigned int offset,
59 int value)
60{
61 spin_lock_irq(&txx9_gpio_lock);
62 txx9_gpio_set_raw(offset, value);
63 __raw_writel(__raw_readl(&txx9_pioptr->dir) | (1 << offset),
64 &txx9_pioptr->dir);
65 mmiowb();
66 spin_unlock_irq(&txx9_gpio_lock);
67 return 0;
68}
69
70static struct gpio_chip txx9_gpio_chip = {
71 .get = txx9_gpio_get,
72 .set = txx9_gpio_set,
73 .direction_input = txx9_gpio_dir_in,
74 .direction_output = txx9_gpio_dir_out,
75 .label = "TXx9",
76};
77
78int __init txx9_gpio_init(unsigned long baseaddr,
79 unsigned int base, unsigned int num)
80{
81 txx9_pioptr = ioremap(baseaddr, sizeof(struct txx9_pio_reg));
82 if (!txx9_pioptr)
83 return -ENODEV;
84 txx9_gpio_chip.base = base;
85 txx9_gpio_chip.ngpio = num;
86 return gpiochip_add(&txx9_gpio_chip);
87}