xref: /openbmc/u-boot/drivers/gpio/mxc_gpio.c (revision 977a39e6)
1 /*
2  * Copyright (C) 2009
3  * Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de>
4  *
5  * Copyright (C) 2011
6  * Stefano Babic, DENX Software Engineering, <sbabic@denx.de>
7  *
8  * See file CREDITS for list of people who contributed to this
9  * project.
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License as
13  * published by the Free Software Foundation; either version 2 of
14  * the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
24  * MA 02111-1307 USA
25  */
26 #include <common.h>
27 #include <asm/arch/imx-regs.h>
28 #include <asm/gpio.h>
29 #include <asm/io.h>
30 #include <errno.h>
31 
32 enum mxc_gpio_direction {
33 	MXC_GPIO_DIRECTION_IN,
34 	MXC_GPIO_DIRECTION_OUT,
35 };
36 
37 
38 /* GPIO port description */
39 static unsigned long gpio_ports[] = {
40 	[0] = GPIO1_BASE_ADDR,
41 	[1] = GPIO2_BASE_ADDR,
42 	[2] = GPIO3_BASE_ADDR,
43 #if defined(CONFIG_MX51) || defined(CONFIG_MX53) || defined(CONFIG_MX6Q)
44 	[3] = GPIO4_BASE_ADDR,
45 #endif
46 #if defined(CONFIG_MX53) || defined(CONFIG_MX6Q)
47 	[4] = GPIO5_BASE_ADDR,
48 	[5] = GPIO6_BASE_ADDR,
49 	[6] = GPIO7_BASE_ADDR,
50 #endif
51 };
52 
53 static int mxc_gpio_direction(unsigned int gpio,
54 	enum mxc_gpio_direction direction)
55 {
56 	unsigned int port = gpio >> 5;
57 	struct gpio_regs *regs;
58 	u32 l;
59 
60 	if (port >= ARRAY_SIZE(gpio_ports))
61 		return -EINVAL;
62 
63 	gpio &= 0x1f;
64 
65 	regs = (struct gpio_regs *)gpio_ports[port];
66 
67 	l = readl(&regs->gpio_dir);
68 
69 	switch (direction) {
70 	case MXC_GPIO_DIRECTION_OUT:
71 		l |= 1 << gpio;
72 		break;
73 	case MXC_GPIO_DIRECTION_IN:
74 		l &= ~(1 << gpio);
75 	}
76 	writel(l, &regs->gpio_dir);
77 
78 	return 0;
79 }
80 
81 void gpio_set_value(int gpio, int value)
82 {
83 	unsigned int port = gpio >> 5;
84 	struct gpio_regs *regs;
85 	u32 l;
86 
87 	if (port >= ARRAY_SIZE(gpio_ports))
88 		return;
89 
90 	gpio &= 0x1f;
91 
92 	regs = (struct gpio_regs *)gpio_ports[port];
93 
94 	l = readl(&regs->gpio_dr);
95 	if (value)
96 		l |= 1 << gpio;
97 	else
98 		l &= ~(1 << gpio);
99 	writel(l, &regs->gpio_dr);
100 }
101 
102 int gpio_get_value(int gpio)
103 {
104 	unsigned int port = gpio >> 5;
105 	struct gpio_regs *regs;
106 	u32 l;
107 
108 	if (port >= ARRAY_SIZE(gpio_ports))
109 		return -EINVAL;
110 
111 	gpio &= 0x1f;
112 
113 	regs = (struct gpio_regs *)gpio_ports[port];
114 
115 	l = (readl(&regs->gpio_dr) >> gpio) & 0x01;
116 
117 	return l;
118 }
119 
120 int gpio_request(int gp, const char *label)
121 {
122 	unsigned int port = gp >> 5;
123 	if (port >= ARRAY_SIZE(gpio_ports))
124 		return -EINVAL;
125 	return 0;
126 }
127 
128 void gpio_free(int gp)
129 {
130 }
131 
132 void gpio_toggle_value(int gp)
133 {
134 	gpio_set_value(gp, !gpio_get_value(gp));
135 }
136 
137 int gpio_direction_input(int gp)
138 {
139 	return mxc_gpio_direction(gp, MXC_GPIO_DIRECTION_IN);
140 }
141 
142 int gpio_direction_output(int gp, int value)
143 {
144 	int ret = mxc_gpio_direction(gp, MXC_GPIO_DIRECTION_OUT);
145 
146 	if (ret < 0)
147 		return ret;
148 
149 	gpio_set_value(gp, value);
150 	return 0;
151 }
152