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
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
|
/* arch/arm/plat-samsung/gpiolib.c
*
* Copyright 2008 Openmoko, Inc.
* Copyright 2008 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
* http://armlinux.simtec.co.uk/
*
* Copyright (c) 2009 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
*
* SAMSUNG - GPIOlib support
*
* 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/irq.h>
#include <linux/io.h>
#include <mach/gpio.h>
#include <plat/gpio-core.h>
#include <plat/gpio-cfg.h>
#include <plat/gpio-cfg-helpers.h>
#ifndef DEBUG_GPIO
#define gpio_dbg(x...) do { } while (0)
#else
#define gpio_dbg(x...) printk(KERN_DEBUG x)
#endif
/* The samsung_gpiolib_4bit routines are to control the gpio banks where
* the gpio configuration register (GPxCON) has 4 bits per GPIO, as the
* following example:
*
* base + 0x00: Control register, 4 bits per gpio
* gpio n: 4 bits starting at (4*n)
* 0000 = input, 0001 = output, others mean special-function
* base + 0x04: Data register, 1 bit per gpio
* bit n: data bit n
*
* Note, since the data register is one bit per gpio and is at base + 0x4
* we can use s3c_gpiolib_get and s3c_gpiolib_set to change the state of
* the output.
*/
static int samsung_gpiolib_4bit_input(struct gpio_chip *chip,
unsigned int offset)
{
struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
void __iomem *base = ourchip->base;
unsigned long con;
con = __raw_readl(base + GPIOCON_OFF);
con &= ~(0xf << con_4bit_shift(offset));
__raw_writel(con, base + GPIOCON_OFF);
gpio_dbg("%s: %p: CON now %08lx\n", __func__, base, con);
return 0;
}
static int samsung_gpiolib_4bit_output(struct gpio_chip *chip,
unsigned int offset, int value)
{
struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
void __iomem *base = ourchip->base;
unsigned long con;
unsigned long dat;
con = __raw_readl(base + GPIOCON_OFF);
con &= ~(0xf << con_4bit_shift(offset));
con |= 0x1 << con_4bit_shift(offset);
dat = __raw_readl(base + GPIODAT_OFF);
if (value)
dat |= 1 << offset;
else
dat &= ~(1 << offset);
__raw_writel(dat, base + GPIODAT_OFF);
__raw_writel(con, base + GPIOCON_OFF);
__raw_writel(dat, base + GPIODAT_OFF);
gpio_dbg("%s: %p: CON %08lx, DAT %08lx\n", __func__, base, con, dat);
return 0;
}
/* The next set of routines are for the case where the GPIO configuration
* registers are 4 bits per GPIO but there is more than one register (the
* bank has more than 8 GPIOs.
*
* This case is the similar to the 4 bit case, but the registers are as
* follows:
*
* base + 0x00: Control register, 4 bits per gpio (lower 8 GPIOs)
* gpio n: 4 bits starting at (4*n)
* 0000 = input, 0001 = output, others mean special-function
* base + 0x04: Control register, 4 bits per gpio (up to 8 additions GPIOs)
* gpio n: 4 bits starting at (4*n)
* 0000 = input, 0001 = output, others mean special-function
* base + 0x08: Data register, 1 bit per gpio
* bit n: data bit n
*
* To allow us to use the s3c_gpiolib_get and s3c_gpiolib_set routines we
* store the 'base + 0x4' address so that these routines see the data
* register at ourchip->base + 0x04.
*/
static int samsung_gpiolib_4bit2_input(struct gpio_chip *chip,
unsigned int offset)
{
struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
void __iomem *base = ourchip->base;
void __iomem *regcon = base;
unsigned long con;
if (offset > 7)
offset -= 8;
else
regcon -= 4;
con = __raw_readl(regcon);
con &= ~(0xf << con_4bit_shift(offset));
__raw_writel(con, regcon);
gpio_dbg("%s: %p: CON %08lx\n", __func__, base, con);
return 0;
}
static int samsung_gpiolib_4bit2_output(struct gpio_chip *chip,
unsigned int offset, int value)
{
struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
void __iomem *base = ourchip->base;
void __iomem *regcon = base;
unsigned long con;
unsigned long dat;
unsigned con_offset = offset;
if (con_offset > 7)
con_offset -= 8;
else
regcon -= 4;
con = __raw_readl(regcon);
con &= ~(0xf << con_4bit_shift(con_offset));
con |= 0x1 << con_4bit_shift(con_offset);
dat = __raw_readl(base + GPIODAT_OFF);
if (value)
dat |= 1 << offset;
else
dat &= ~(1 << offset);
__raw_writel(dat, base + GPIODAT_OFF);
__raw_writel(con, regcon);
__raw_writel(dat, base + GPIODAT_OFF);
gpio_dbg("%s: %p: CON %08lx, DAT %08lx\n", __func__, base, con, dat);
return 0;
}
void __init samsung_gpiolib_add_4bit(struct s3c_gpio_chip *chip)
{
chip->chip.direction_input = samsung_gpiolib_4bit_input;
chip->chip.direction_output = samsung_gpiolib_4bit_output;
chip->pm = __gpio_pm(&s3c_gpio_pm_4bit);
}
void __init samsung_gpiolib_add_4bit2(struct s3c_gpio_chip *chip)
{
chip->chip.direction_input = samsung_gpiolib_4bit2_input;
chip->chip.direction_output = samsung_gpiolib_4bit2_output;
chip->pm = __gpio_pm(&s3c_gpio_pm_4bit);
}
void __init samsung_gpiolib_add_4bit_chips(struct s3c_gpio_chip *chip,
int nr_chips)
{
for (; nr_chips > 0; nr_chips--, chip++) {
samsung_gpiolib_add_4bit(chip);
s3c_gpiolib_add(chip);
}
}
void __init samsung_gpiolib_add_4bit2_chips(struct s3c_gpio_chip *chip,
int nr_chips)
{
for (; nr_chips > 0; nr_chips--, chip++) {
samsung_gpiolib_add_4bit2(chip);
s3c_gpiolib_add(chip);
}
}
|
