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
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
|
/*
* arch/arm/plat-orion/gpio.c
*
* Marvell Orion SoC GPIO handling.
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/bitops.h>
#include <linux/io.h>
#include <asm/gpio.h>
static DEFINE_SPINLOCK(gpio_lock);
static const char *gpio_label[GPIO_MAX]; /* non null for allocated GPIOs */
static unsigned long gpio_valid[BITS_TO_LONGS(GPIO_MAX)];
static inline void __set_direction(unsigned pin, int input)
{
u32 u;
u = readl(GPIO_IO_CONF(pin));
if (input)
u |= 1 << (pin & 31);
else
u &= ~(1 << (pin & 31));
writel(u, GPIO_IO_CONF(pin));
}
static void __set_level(unsigned pin, int high)
{
u32 u;
u = readl(GPIO_OUT(pin));
if (high)
u |= 1 << (pin & 31);
else
u &= ~(1 << (pin & 31));
writel(u, GPIO_OUT(pin));
}
/*
* GENERIC_GPIO primitives.
*/
int gpio_direction_input(unsigned pin)
{
unsigned long flags;
if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
pr_debug("%s: invalid GPIO %d\n", __func__, pin);
return -EINVAL;
}
spin_lock_irqsave(&gpio_lock, flags);
/*
* Some callers might not have used gpio_request(),
* so flag this pin as requested now.
*/
if (gpio_label[pin] == NULL)
gpio_label[pin] = "?";
/*
* Configure GPIO direction.
*/
__set_direction(pin, 1);
spin_unlock_irqrestore(&gpio_lock, flags);
return 0;
}
EXPORT_SYMBOL(gpio_direction_input);
int gpio_direction_output(unsigned pin, int value)
{
unsigned long flags;
u32 u;
if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
pr_debug("%s: invalid GPIO %d\n", __func__, pin);
return -EINVAL;
}
spin_lock_irqsave(&gpio_lock, flags);
/*
* Some callers might not have used gpio_request(),
* so flag this pin as requested now.
*/
if (gpio_label[pin] == NULL)
gpio_label[pin] = "?";
/*
* Disable blinking.
*/
u = readl(GPIO_BLINK_EN(pin));
u &= ~(1 << (pin & 31));
writel(u, GPIO_BLINK_EN(pin));
/*
* Configure GPIO output value.
*/
__set_level(pin, value);
/*
* Configure GPIO direction.
*/
__set_direction(pin, 0);
spin_unlock_irqrestore(&gpio_lock, flags);
return 0;
}
EXPORT_SYMBOL(gpio_direction_output);
int gpio_get_value(unsigned pin)
{
int val;
if (readl(GPIO_IO_CONF(pin)) & (1 << (pin & 31)))
val = readl(GPIO_DATA_IN(pin)) ^ readl(GPIO_IN_POL(pin));
else
val = readl(GPIO_OUT(pin));
return (val >> (pin & 31)) & 1;
}
EXPORT_SYMBOL(gpio_get_value);
void gpio_set_value(unsigned pin, int value)
{
unsigned long flags;
u32 u;
spin_lock_irqsave(&gpio_lock, flags);
/*
* Disable blinking.
*/
u = readl(GPIO_BLINK_EN(pin));
u &= ~(1 << (pin & 31));
writel(u, GPIO_BLINK_EN(pin));
/*
* Configure GPIO output value.
*/
__set_level(pin, value);
spin_unlock_irqrestore(&gpio_lock, flags);
}
EXPORT_SYMBOL(gpio_set_value);
int gpio_request(unsigned pin, const char *label)
{
unsigned long flags;
int ret;
if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
pr_debug("%s: invalid GPIO %d\n", __func__, pin);
return -EINVAL;
}
spin_lock_irqsave(&gpio_lock, flags);
if (gpio_label[pin] == NULL) {
gpio_label[pin] = label ? label : "?";
ret = 0;
} else {
pr_debug("%s: GPIO %d already used as %s\n",
__func__, pin, gpio_label[pin]);
ret = -EBUSY;
}
spin_unlock_irqrestore(&gpio_lock, flags);
return ret;
}
EXPORT_SYMBOL(gpio_request);
void gpio_free(unsigned pin)
{
if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
pr_debug("%s: invalid GPIO %d\n", __func__, pin);
return;
}
if (gpio_label[pin] == NULL)
pr_warning("%s: GPIO %d already freed\n", __func__, pin);
else
gpio_label[pin] = NULL;
}
EXPORT_SYMBOL(gpio_free);
/*
* Orion-specific GPIO API extensions.
*/
void __init orion_gpio_set_unused(unsigned pin)
{
/*
* Configure as output, drive low.
*/
__set_level(pin, 0);
__set_direction(pin, 0);
}
void __init orion_gpio_set_valid(unsigned pin, int valid)
{
if (valid)
__set_bit(pin, gpio_valid);
else
__clear_bit(pin, gpio_valid);
}
void orion_gpio_set_blink(unsigned pin, int blink)
{
unsigned long flags;
u32 u;
spin_lock_irqsave(&gpio_lock, flags);
/*
* Set output value to zero.
*/
__set_level(pin, 0);
u = readl(GPIO_BLINK_EN(pin));
if (blink)
u |= 1 << (pin & 31);
else
u &= ~(1 << (pin & 31));
writel(u, GPIO_BLINK_EN(pin));
spin_unlock_irqrestore(&gpio_lock, flags);
}
EXPORT_SYMBOL(orion_gpio_set_blink);
|
