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authorBen Dooks <ben-linux@fluff.org>2008-10-31 12:14:31 -0400
committerBen Dooks <ben-linux@fluff.org>2008-12-15 18:33:20 -0500
commit7db6c82a37beabef7b76d232e3d20efacd74bd3a (patch)
treedcd673614883eba53a207aca9f136c6e7b490c4e /arch/arm/plat-s3c/gpio.c
parentefd3a8eb150e383305c36eedc78c29cab910158e (diff)
[ARM] S3C: Move common GPIO code from plat-s3c24xx
Move the common parts of the GPIO code into plat-s3c for use with both the s3c24xx and s3c64xx systems. Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Diffstat (limited to 'arch/arm/plat-s3c/gpio.c')
-rw-r--r--arch/arm/plat-s3c/gpio.c128
1 files changed, 128 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c/gpio.c b/arch/arm/plat-s3c/gpio.c
new file mode 100644
index 00000000000..f035d4550c4
--- /dev/null
+++ b/arch/arm/plat-s3c/gpio.c
@@ -0,0 +1,128 @@
1/* linux/arch/arm/plat-s3c/gpio.c
2 *
3 * Copyright 2008 Simtec Electronics
4 * Ben Dooks <ben@simtec.co.uk>
5 * http://armlinux.simtec.co.uk/
6 *
7 * S3C series GPIO core
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12*/
13
14#include <linux/kernel.h>
15#include <linux/init.h>
16#include <linux/io.h>
17#include <linux/gpio.h>
18
19#include <plat/gpio-core.h>
20
21/* Default routines for controlling GPIO, based on the original S3C24XX
22 * GPIO functions which deal with the case where each gpio bank of the
23 * chip is as following:
24 *
25 * base + 0x00: Control register, 2 bits per gpio
26 * gpio n: 2 bits starting at (2*n)
27 * 00 = input, 01 = output, others mean special-function
28 * base + 0x04: Data register, 1 bit per gpio
29 * bit n: data bit n
30*/
31
32static int s3c_gpiolib_input(struct gpio_chip *chip, unsigned offset)
33{
34 struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
35 void __iomem *base = ourchip->base;
36 unsigned long flags;
37 unsigned long con;
38
39 local_irq_save(flags);
40
41 con = __raw_readl(base + 0x00);
42 con &= ~(3 << (offset * 2));
43
44 __raw_writel(con, base + 0x00);
45
46 local_irq_restore(flags);
47 return 0;
48}
49
50static int s3c_gpiolib_output(struct gpio_chip *chip,
51 unsigned offset, int value)
52{
53 struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
54 void __iomem *base = ourchip->base;
55 unsigned long flags;
56 unsigned long dat;
57 unsigned long con;
58
59 local_irq_save(flags);
60
61 dat = __raw_readl(base + 0x04);
62 dat &= ~(1 << offset);
63 if (value)
64 dat |= 1 << offset;
65 __raw_writel(dat, base + 0x04);
66
67 con = __raw_readl(base + 0x00);
68 con &= ~(3 << (offset * 2));
69 con |= 1 << (offset * 2);
70
71 __raw_writel(con, base + 0x00);
72 __raw_writel(dat, base + 0x04);
73
74 local_irq_restore(flags);
75 return 0;
76}
77
78static void s3c_gpiolib_set(struct gpio_chip *chip,
79 unsigned offset, int value)
80{
81 struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
82 void __iomem *base = ourchip->base;
83 unsigned long flags;
84 unsigned long dat;
85
86 local_irq_save(flags);
87
88 dat = __raw_readl(base + 0x04);
89 dat &= ~(1 << offset);
90 if (value)
91 dat |= 1 << offset;
92 __raw_writel(dat, base + 0x04);
93
94 local_irq_restore(flags);
95}
96
97static int s3c_gpiolib_get(struct gpio_chip *chip, unsigned offset)
98{
99 struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
100 unsigned long val;
101
102 val = __raw_readl(ourchip->base + 0x04);
103 val >>= offset;
104 val &= 1;
105
106 return val;
107}
108
109__init void s3c_gpiolib_add(struct s3c_gpio_chip *chip)
110{
111 struct gpio_chip *gc = &chip->chip;
112
113 BUG_ON(!chip->base);
114 BUG_ON(!gc->label);
115 BUG_ON(!gc->ngpio);
116
117 if (!gc->direction_input)
118 gc->direction_input = s3c_gpiolib_input;
119 if (!gc->direction_output)
120 gc->direction_output = s3c_gpiolib_output;
121 if (!gc->set)
122 gc->set = s3c_gpiolib_set;
123 if (!gc->get)
124 gc->get = s3c_gpiolib_get;
125
126 /* gpiochip_add() prints own failure message on error. */
127 gpiochip_add(gc);
128}