1 /*
2 * STLS2F GPIO Support
3 *
4 * Copyright (c) 2008 Richard Liu, STMicroelectronics <richard.liu@st.com>
5 * Copyright (c) 2008-2010 Arnaud Patard <apatard@mandriva.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 */
12
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/module.h>
16 #include <linux/spinlock.h>
17 #include <linux/err.h>
18 #include <asm/types.h>
19 #include <loongson.h>
20 #include <linux/gpio.h>
21
22 #define STLS2F_N_GPIO 4
23 #define STLS2F_GPIO_IN_OFFSET 16
24
25 static DEFINE_SPINLOCK(gpio_lock);
26
gpio_get_value(unsigned gpio)27 int gpio_get_value(unsigned gpio)
28 {
29 u32 val;
30 u32 mask;
31
32 if (gpio >= STLS2F_N_GPIO)
33 return __gpio_get_value(gpio);
34
35 mask = 1 << (gpio + STLS2F_GPIO_IN_OFFSET);
36 spin_lock(&gpio_lock);
37 val = LOONGSON_GPIODATA;
38 spin_unlock(&gpio_lock);
39
40 return ((val & mask) != 0);
41 }
42 EXPORT_SYMBOL(gpio_get_value);
43
gpio_set_value(unsigned gpio,int state)44 void gpio_set_value(unsigned gpio, int state)
45 {
46 u32 val;
47 u32 mask;
48
49 if (gpio >= STLS2F_N_GPIO) {
50 __gpio_set_value(gpio, state);
51 return ;
52 }
53
54 mask = 1 << gpio;
55
56 spin_lock(&gpio_lock);
57 val = LOONGSON_GPIODATA;
58 if (state)
59 val |= mask;
60 else
61 val &= (~mask);
62 LOONGSON_GPIODATA = val;
63 spin_unlock(&gpio_lock);
64 }
65 EXPORT_SYMBOL(gpio_set_value);
66
gpio_cansleep(unsigned gpio)67 int gpio_cansleep(unsigned gpio)
68 {
69 if (gpio < STLS2F_N_GPIO)
70 return 0;
71 else
72 return __gpio_cansleep(gpio);
73 }
74 EXPORT_SYMBOL(gpio_cansleep);
75
ls2f_gpio_direction_input(struct gpio_chip * chip,unsigned gpio)76 static int ls2f_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
77 {
78 u32 temp;
79 u32 mask;
80
81 if (gpio >= STLS2F_N_GPIO)
82 return -EINVAL;
83
84 spin_lock(&gpio_lock);
85 mask = 1 << gpio;
86 temp = LOONGSON_GPIOIE;
87 temp |= mask;
88 LOONGSON_GPIOIE = temp;
89 spin_unlock(&gpio_lock);
90
91 return 0;
92 }
93
ls2f_gpio_direction_output(struct gpio_chip * chip,unsigned gpio,int level)94 static int ls2f_gpio_direction_output(struct gpio_chip *chip,
95 unsigned gpio, int level)
96 {
97 u32 temp;
98 u32 mask;
99
100 if (gpio >= STLS2F_N_GPIO)
101 return -EINVAL;
102
103 gpio_set_value(gpio, level);
104 spin_lock(&gpio_lock);
105 mask = 1 << gpio;
106 temp = LOONGSON_GPIOIE;
107 temp &= (~mask);
108 LOONGSON_GPIOIE = temp;
109 spin_unlock(&gpio_lock);
110
111 return 0;
112 }
113
ls2f_gpio_get_value(struct gpio_chip * chip,unsigned gpio)114 static int ls2f_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
115 {
116 return gpio_get_value(gpio);
117 }
118
ls2f_gpio_set_value(struct gpio_chip * chip,unsigned gpio,int value)119 static void ls2f_gpio_set_value(struct gpio_chip *chip,
120 unsigned gpio, int value)
121 {
122 gpio_set_value(gpio, value);
123 }
124
125 static struct gpio_chip ls2f_chip = {
126 .label = "ls2f",
127 .direction_input = ls2f_gpio_direction_input,
128 .get = ls2f_gpio_get_value,
129 .direction_output = ls2f_gpio_direction_output,
130 .set = ls2f_gpio_set_value,
131 .base = 0,
132 .ngpio = STLS2F_N_GPIO,
133 };
134
ls2f_gpio_setup(void)135 static int __init ls2f_gpio_setup(void)
136 {
137 return gpiochip_add(&ls2f_chip);
138 }
139 arch_initcall(ls2f_gpio_setup);
140