Warning: That file was not part of the compilation database. It may have many parsing errors.

1/*
2 * Loongson-2F/3A/3B 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 * Copyright (c) 2013 Hongbing Hu <huhb@lemote.com>
7 * Copyright (c) 2014 Huacai Chen <chenhc@lemote.com>
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 as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 */
14
15#include <linux/kernel.h>
16#include <linux/init.h>
17#include <linux/module.h>
18#include <linux/spinlock.h>
19#include <linux/err.h>
20#include <linux/gpio/driver.h>
21#include <linux/platform_device.h>
22#include <linux/bitops.h>
23#include <asm/types.h>
24#include <loongson.h>
25
26#define STLS2F_N_GPIO 4
27#define STLS3A_N_GPIO 16
28
29#ifdef CONFIG_CPU_LOONGSON3
30#define LOONGSON_N_GPIO STLS3A_N_GPIO
31#else
32#define LOONGSON_N_GPIO STLS2F_N_GPIO
33#endif
34
35/*
36 * Offset into the register where we read lines, we write them from offset 0.
37 * This offset is the only thing that stand between us and using
38 * GPIO_GENERIC.
39 */
40#define LOONGSON_GPIO_IN_OFFSET 16
41
42static DEFINE_SPINLOCK(gpio_lock);
43
44static int loongson_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
45{
46 u32 val;
47
48 spin_lock(&gpio_lock);
49 val = LOONGSON_GPIODATA;
50 spin_unlock(&gpio_lock);
51
52 return !!(val & BIT(gpio + LOONGSON_GPIO_IN_OFFSET));
53}
54
55static void loongson_gpio_set_value(struct gpio_chip *chip,
56 unsigned gpio, int value)
57{
58 u32 val;
59
60 spin_lock(&gpio_lock);
61 val = LOONGSON_GPIODATA;
62 if (value)
63 val |= BIT(gpio);
64 else
65 val &= ~BIT(gpio);
66 LOONGSON_GPIODATA = val;
67 spin_unlock(&gpio_lock);
68}
69
70static int loongson_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
71{
72 u32 temp;
73
74 spin_lock(&gpio_lock);
75 temp = LOONGSON_GPIOIE;
76 temp |= BIT(gpio);
77 LOONGSON_GPIOIE = temp;
78 spin_unlock(&gpio_lock);
79
80 return 0;
81}
82
83static int loongson_gpio_direction_output(struct gpio_chip *chip,
84 unsigned gpio, int level)
85{
86 u32 temp;
87
88 loongson_gpio_set_value(chip, gpio, level);
89 spin_lock(&gpio_lock);
90 temp = LOONGSON_GPIOIE;
91 temp &= ~BIT(gpio);
92 LOONGSON_GPIOIE = temp;
93 spin_unlock(&gpio_lock);
94
95 return 0;
96}
97
98static int loongson_gpio_probe(struct platform_device *pdev)
99{
100 struct gpio_chip *gc;
101 struct device *dev = &pdev->dev;
102
103 gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
104 if (!gc)
105 return -ENOMEM;
106
107 gc->label = "loongson-gpio-chip";
108 gc->base = 0;
109 gc->ngpio = LOONGSON_N_GPIO;
110 gc->get = loongson_gpio_get_value;
111 gc->set = loongson_gpio_set_value;
112 gc->direction_input = loongson_gpio_direction_input;
113 gc->direction_output = loongson_gpio_direction_output;
114
115 return gpiochip_add_data(gc, NULL);
116}
117
118static struct platform_driver loongson_gpio_driver = {
119 .driver = {
120 .name = "loongson-gpio",
121 },
122 .probe = loongson_gpio_probe,
123};
124
125static int __init loongson_gpio_setup(void)
126{
127 struct platform_device *pdev;
128 int ret;
129
130 ret = platform_driver_register(&loongson_gpio_driver);
131 if (ret) {
132 pr_err("error registering loongson GPIO driver\n");
133 return ret;
134 }
135
136 pdev = platform_device_register_simple("loongson-gpio", -1, NULL, 0);
137 return PTR_ERR_OR_ZERO(pdev);
138}
139postcore_initcall(loongson_gpio_setup);
140

Warning: That file was not part of the compilation database. It may have many parsing errors.