xref: /openbmc/u-boot/drivers/gpio/mxc_gpio.c (revision 5094fbf7)
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_MX51) || defined(CONFIG_MX53) || \
45 		defined(CONFIG_MX6Q)
46 	[3] = GPIO4_BASE_ADDR,
47 #endif
48 #if defined(CONFIG_MX53) || defined(CONFIG_MX6Q)
49 	[4] = GPIO5_BASE_ADDR,
50 	[5] = GPIO6_BASE_ADDR,
51 	[6] = GPIO7_BASE_ADDR,
52 #endif
53 };
54 
55 static int mxc_gpio_direction(unsigned int gpio,
56 	enum mxc_gpio_direction direction)
57 {
58 	unsigned int port = GPIO_TO_PORT(gpio);
59 	struct gpio_regs *regs;
60 	u32 l;
61 
62 	if (port >= ARRAY_SIZE(gpio_ports))
63 		return -1;
64 
65 	gpio &= 0x1f;
66 
67 	regs = (struct gpio_regs *)gpio_ports[port];
68 
69 	l = readl(&regs->gpio_dir);
70 
71 	switch (direction) {
72 	case MXC_GPIO_DIRECTION_OUT:
73 		l |= 1 << gpio;
74 		break;
75 	case MXC_GPIO_DIRECTION_IN:
76 		l &= ~(1 << gpio);
77 	}
78 	writel(l, &regs->gpio_dir);
79 
80 	return 0;
81 }
82 
83 int gpio_set_value(unsigned gpio, int value)
84 {
85 	unsigned int port = GPIO_TO_PORT(gpio);
86 	struct gpio_regs *regs;
87 	u32 l;
88 
89 	if (port >= ARRAY_SIZE(gpio_ports))
90 		return -1;
91 
92 	gpio &= 0x1f;
93 
94 	regs = (struct gpio_regs *)gpio_ports[port];
95 
96 	l = readl(&regs->gpio_dr);
97 	if (value)
98 		l |= 1 << gpio;
99 	else
100 		l &= ~(1 << gpio);
101 	writel(l, &regs->gpio_dr);
102 
103 	return 0;
104 }
105 
106 int gpio_get_value(unsigned gpio)
107 {
108 	unsigned int port = GPIO_TO_PORT(gpio);
109 	struct gpio_regs *regs;
110 	u32 val;
111 
112 	if (port >= ARRAY_SIZE(gpio_ports))
113 		return -1;
114 
115 	gpio &= 0x1f;
116 
117 	regs = (struct gpio_regs *)gpio_ports[port];
118 
119 	val = (readl(&regs->gpio_dr) >> gpio) & 0x01;
120 
121 	return val;
122 }
123 
124 int gpio_request(unsigned gpio, const char *label)
125 {
126 	unsigned int port = GPIO_TO_PORT(gpio);
127 	if (port >= ARRAY_SIZE(gpio_ports))
128 		return -1;
129 	return 0;
130 }
131 
132 int gpio_free(unsigned gpio)
133 {
134 	return 0;
135 }
136 
137 int gpio_direction_input(unsigned gpio)
138 {
139 	return mxc_gpio_direction(gpio, MXC_GPIO_DIRECTION_IN);
140 }
141 
142 int gpio_direction_output(unsigned gpio, int value)
143 {
144 	int ret = mxc_gpio_direction(gpio, MXC_GPIO_DIRECTION_OUT);
145 
146 	if (ret < 0)
147 		return ret;
148 
149 	return gpio_set_value(gpio, value);
150 }
151