summaryrefslogtreecommitdiffstats
path: root/arch/mips/ar7/gpio.c
blob: 0e9f4e13f427d0c3e879f3b941533ec18b1d63a2 (plain)
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
/*
 * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
 * Copyright (C) 2007 Eugene Konev <ejka@openwrt.org>
 * Copyright (C) 2009 Florian Fainelli <florian@openwrt.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <linux/module.h>
#include <linux/gpio.h>

#include <asm/mach-ar7/gpio.h>

struct ar7_gpio_chip {
	void __iomem	*regs;
	struct gpio_chip chip;
};

static int ar7_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{
	struct ar7_gpio_chip *gpch =
				container_of(chip, struct ar7_gpio_chip, chip);
	void __iomem *gpio_in = gpch->regs + AR7_GPIO_INPUT;

	return readl(gpio_in) & (1 << gpio);
}

static void ar7_gpio_set_value(struct gpio_chip *chip,
				unsigned gpio, int value)
{
	struct ar7_gpio_chip *gpch =
				container_of(chip, struct ar7_gpio_chip, chip);
	void __iomem *gpio_out = gpch->regs + AR7_GPIO_OUTPUT;
	unsigned tmp;

	tmp = readl(gpio_out) & ~(1 << gpio);
	if (value)
		tmp |= 1 << gpio;
	writel(tmp, gpio_out);
}

static int ar7_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
{
	struct ar7_gpio_chip *gpch =
				container_of(chip, struct ar7_gpio_chip, chip);
	void __iomem *gpio_dir = gpch->regs + AR7_GPIO_DIR;

	writel(readl(gpio_dir) | (1 << gpio), gpio_dir);

	return 0;
}

static int ar7_gpio_direction_output(struct gpio_chip *chip,
					unsigned gpio, int value)
{
	struct ar7_gpio_chip *gpch =
				container_of(chip, struct ar7_gpio_chip, chip);
	void __iomem *gpio_dir = gpch->regs + AR7_GPIO_DIR;

	ar7_gpio_set_value(chip, gpio, value);
	writel(readl(gpio_dir) & ~(1 << gpio), gpio_dir);

	return 0;
}

static struct ar7_gpio_chip ar7_gpio_chip = {
	.chip = {
		.label		= "ar7-gpio",
		.direction_input	= ar7_gpio_direction_input,
		.direction_output	= ar7_gpio_direction_output,
		.set			= ar7_gpio_set_value,
		.get			= ar7_gpio_get_value,
		.base			= 0,
		.ngpio			= AR7_GPIO_MAX,
	}
};

int ar7_gpio_enable(unsigned gpio)
{
	void __iomem *gpio_en = ar7_gpio_chip.regs + AR7_GPIO_ENABLE;

	writel(readl(gpio_en) | (1 << gpio), gpio_en);

	return 0;
}
EXPORT_SYMBOL(ar7_gpio_enable);

int ar7_gpio_disable(unsigned gpio)
{
	void __iomem *gpio_en = ar7_gpio_chip.regs + AR7_GPIO_ENABLE;

	writel(readl(gpio_en) & ~(1 << gpio), gpio_en);

	return 0;
}
EXPORT_SYMBOL(ar7_gpio_disable);

static int __init ar7_gpio_init(void)
{
	int ret;

	ar7_gpio_chip.regs = ioremap_nocache(AR7_REGS_GPIO,
					AR7_REGS_GPIO + 0x10);

	if (!ar7_gpio_chip.regs) {
		printk(KERN_ERR "ar7-gpio: failed to ioremap regs\n");
		return -ENOMEM;
	}

	ret = gpiochip_add(&ar7_gpio_chip.chip);
	if (ret) {
		printk(KERN_ERR "ar7-gpio: failed to add gpiochip\n");
		return ret;
	}
	printk(KERN_INFO "ar7-gpio: registered %d GPIOs\n",
				ar7_gpio_chip.chip.ngpio);
	return ret;
}
arch_initcall(ar7_gpio_init);