xref: /openbmc/u-boot/drivers/gpio/mxc_gpio.c (revision 713cb680)
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 #define GPIO_TO_PORT(n)		(n / 32)
38 
39 /* GPIO port description */
40 static unsigned long gpio_ports[] = {
41 	[0] = GPIO1_BASE_ADDR,
42 	[1] = GPIO2_BASE_ADDR,
43 	[2] = GPIO3_BASE_ADDR,
44 #if defined(CONFIG_MX25) || defined(CONFIG_MX27) || defined(CONFIG_MX51) || \
45 		defined(CONFIG_MX53) || defined(CONFIG_MX6)
46 	[3] = GPIO4_BASE_ADDR,
47 #endif
48 #if defined(CONFIG_MX27) || defined(CONFIG_MX53) || defined(CONFIG_MX6)
49 	[4] = GPIO5_BASE_ADDR,
50 	[5] = GPIO6_BASE_ADDR,
51 #endif
52 #if defined(CONFIG_MX53) || defined(CONFIG_MX6)
53 	[6] = GPIO7_BASE_ADDR,
54 #endif
55 };
56 
57 static int mxc_gpio_direction(unsigned int gpio,
58 	enum mxc_gpio_direction direction)
59 {
60 	unsigned int port = GPIO_TO_PORT(gpio);
61 	struct gpio_regs *regs;
62 	u32 l;
63 
64 	if (port >= ARRAY_SIZE(gpio_ports))
65 		return -1;
66 
67 	gpio &= 0x1f;
68 
69 	regs = (struct gpio_regs *)gpio_ports[port];
70 
71 	l = readl(&regs->gpio_dir);
72 
73 	switch (direction) {
74 	case MXC_GPIO_DIRECTION_OUT:
75 		l |= 1 << gpio;
76 		break;
77 	case MXC_GPIO_DIRECTION_IN:
78 		l &= ~(1 << gpio);
79 	}
80 	writel(l, &regs->gpio_dir);
81 
82 	return 0;
83 }
84 
85 int gpio_set_value(unsigned gpio, int value)
86 {
87 	unsigned int port = GPIO_TO_PORT(gpio);
88 	struct gpio_regs *regs;
89 	u32 l;
90 
91 	if (port >= ARRAY_SIZE(gpio_ports))
92 		return -1;
93 
94 	gpio &= 0x1f;
95 
96 	regs = (struct gpio_regs *)gpio_ports[port];
97 
98 	l = readl(&regs->gpio_dr);
99 	if (value)
100 		l |= 1 << gpio;
101 	else
102 		l &= ~(1 << gpio);
103 	writel(l, &regs->gpio_dr);
104 
105 	return 0;
106 }
107 
108 int gpio_get_value(unsigned gpio)
109 {
110 	unsigned int port = GPIO_TO_PORT(gpio);
111 	struct gpio_regs *regs;
112 	u32 val;
113 
114 	if (port >= ARRAY_SIZE(gpio_ports))
115 		return -1;
116 
117 	gpio &= 0x1f;
118 
119 	regs = (struct gpio_regs *)gpio_ports[port];
120 
121 	val = (readl(&regs->gpio_psr) >> gpio) & 0x01;
122 
123 	return val;
124 }
125 
126 int gpio_request(unsigned gpio, const char *label)
127 {
128 	unsigned int port = GPIO_TO_PORT(gpio);
129 	if (port >= ARRAY_SIZE(gpio_ports))
130 		return -1;
131 	return 0;
132 }
133 
134 int gpio_free(unsigned gpio)
135 {
136 	return 0;
137 }
138 
139 int gpio_direction_input(unsigned gpio)
140 {
141 	return mxc_gpio_direction(gpio, MXC_GPIO_DIRECTION_IN);
142 }
143 
144 int gpio_direction_output(unsigned gpio, int value)
145 {
146 	int ret = mxc_gpio_direction(gpio, MXC_GPIO_DIRECTION_OUT);
147 
148 	if (ret < 0)
149 		return ret;
150 
151 	return gpio_set_value(gpio, value);
152 }
153