1 /*
2  * arch/arm/plat-iop/gpio.c
3  * GPIO handling for Intel IOP3xx processors.
4  *
5  * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or (at
10  * your option) any later version.
11  */
12 
13 #include <linux/device.h>
14 #include <linux/init.h>
15 #include <linux/types.h>
16 #include <linux/errno.h>
17 #include <linux/gpio.h>
18 #include <linux/export.h>
19 #include <asm/hardware/iop3xx.h>
20 
gpio_line_config(int line,int direction)21 void gpio_line_config(int line, int direction)
22 {
23 	unsigned long flags;
24 
25 	local_irq_save(flags);
26 	if (direction == GPIO_IN) {
27 		*IOP3XX_GPOE |= 1 << line;
28 	} else if (direction == GPIO_OUT) {
29 		*IOP3XX_GPOE &= ~(1 << line);
30 	}
31 	local_irq_restore(flags);
32 }
33 EXPORT_SYMBOL(gpio_line_config);
34 
gpio_line_get(int line)35 int gpio_line_get(int line)
36 {
37 	return !!(*IOP3XX_GPID & (1 << line));
38 }
39 EXPORT_SYMBOL(gpio_line_get);
40 
gpio_line_set(int line,int value)41 void gpio_line_set(int line, int value)
42 {
43 	unsigned long flags;
44 
45 	local_irq_save(flags);
46 	if (value == GPIO_LOW) {
47 		*IOP3XX_GPOD &= ~(1 << line);
48 	} else if (value == GPIO_HIGH) {
49 		*IOP3XX_GPOD |= 1 << line;
50 	}
51 	local_irq_restore(flags);
52 }
53 EXPORT_SYMBOL(gpio_line_set);
54 
iop3xx_gpio_direction_input(struct gpio_chip * chip,unsigned gpio)55 static int iop3xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
56 {
57 	gpio_line_config(gpio, GPIO_IN);
58 	return 0;
59 }
60 
iop3xx_gpio_direction_output(struct gpio_chip * chip,unsigned gpio,int level)61 static int iop3xx_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int level)
62 {
63 	gpio_line_set(gpio, level);
64 	gpio_line_config(gpio, GPIO_OUT);
65 	return 0;
66 }
67 
iop3xx_gpio_get_value(struct gpio_chip * chip,unsigned gpio)68 static int iop3xx_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
69 {
70 	return gpio_line_get(gpio);
71 }
72 
iop3xx_gpio_set_value(struct gpio_chip * chip,unsigned gpio,int value)73 static void iop3xx_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
74 {
75 	gpio_line_set(gpio, value);
76 }
77 
78 static struct gpio_chip iop3xx_chip = {
79 	.label			= "iop3xx",
80 	.direction_input	= iop3xx_gpio_direction_input,
81 	.get			= iop3xx_gpio_get_value,
82 	.direction_output	= iop3xx_gpio_direction_output,
83 	.set			= iop3xx_gpio_set_value,
84 	.base			= 0,
85 	.ngpio			= IOP3XX_N_GPIOS,
86 };
87 
iop3xx_gpio_setup(void)88 static int __init iop3xx_gpio_setup(void)
89 {
90 	return gpiochip_add(&iop3xx_chip);
91 }
92 arch_initcall(iop3xx_gpio_setup);
93