1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
|
/* linux/arch/arm/plat-s3c/gpio.c
*
* Copyright 2008 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
* http://armlinux.simtec.co.uk/
*
* S3C series GPIO core
*
* 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/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <plat/gpio-core.h>
#ifdef CONFIG_S3C_GPIO_TRACK
struct s3c_gpio_chip *s3c_gpios[S3C_GPIO_END];
static __init void s3c_gpiolib_track(struct s3c_gpio_chip *chip)
{
unsigned int gpn;
int i;
gpn = chip->chip.base;
for (i = 0; i < chip->chip.ngpio; i++, gpn++) {
BUG_ON(gpn > ARRAY_SIZE(s3c_gpios));
s3c_gpios[gpn] = chip;
}
}
#endif /* CONFIG_S3C_GPIO_TRACK */
/* Default routines for controlling GPIO, based on the original S3C24XX
* GPIO functions which deal with the case where each gpio bank of the
* chip is as following:
*
* base + 0x00: Control register, 2 bits per gpio
* gpio n: 2 bits starting at (2*n)
* 00 = input, 01 = output, others mean special-function
* base + 0x04: Data register, 1 bit per gpio
* bit n: data bit n
*/
static int s3c_gpiolib_input(struct gpio_chip *chip, unsigned offset)
{
struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
void __iomem *base = ourchip->base;
unsigned long flags;
unsigned long con;
local_irq_save(flags);
con = __raw_readl(base + 0x00);
con &= ~(3 << (offset * 2));
__raw_writel(con, base + 0x00);
local_irq_restore(flags);
return 0;
}
static int s3c_gpiolib_output(struct gpio_chip *chip,
unsigned offset, int value)
{
struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
void __iomem *base = ourchip->base;
unsigned long flags;
unsigned long dat;
unsigned long con;
local_irq_save(flags);
dat = __raw_readl(base + 0x04);
dat &= ~(1 << offset);
if (value)
dat |= 1 << offset;
__raw_writel(dat, base + 0x04);
con = __raw_readl(base + 0x00);
con &= ~(3 << (offset * 2));
con |= 1 << (offset * 2);
__raw_writel(con, base + 0x00);
__raw_writel(dat, base + 0x04);
local_irq_restore(flags);
return 0;
}
static void s3c_gpiolib_set(struct gpio_chip *chip,
unsigned offset, int value)
{
struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
void __iomem *base = ourchip->base;
unsigned long flags;
unsigned long dat;
local_irq_save(flags);
dat = __raw_readl(base + 0x04);
dat &= ~(1 << offset);
if (value)
dat |= 1 << offset;
__raw_writel(dat, base + 0x04);
local_irq_restore(flags);
}
static int s3c_gpiolib_get(struct gpio_chip *chip, unsigned offset)
{
struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
unsigned long val;
val = __raw_readl(ourchip->base + 0x04);
val >>= offset;
val &= 1;
return val;
}
__init void s3c_gpiolib_add(struct s3c_gpio_chip *chip)
{
struct gpio_chip *gc = &chip->chip;
int ret;
BUG_ON(!chip->base);
BUG_ON(!gc->label);
BUG_ON(!gc->ngpio);
if (!gc->direction_input)
gc->direction_input = s3c_gpiolib_input;
if (!gc->direction_output)
gc->direction_output = s3c_gpiolib_output;
if (!gc->set)
gc->set = s3c_gpiolib_set;
if (!gc->get)
gc->get = s3c_gpiolib_get;
/* gpiochip_add() prints own failure message on error. */
ret = gpiochip_add(gc);
if (ret >= 0)
s3c_gpiolib_track(chip);
}
|
