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 <asm/hardware/iop3xx.h>
19 
gpio_line_config(int line,int direction)20 void gpio_line_config(int line, int direction)
21 {
22 	unsigned long flags;
23 
24 	local_irq_save(flags);
25 	if (direction == GPIO_IN) {
26 		*IOP3XX_GPOE |= 1 << line;
27 	} else if (direction == GPIO_OUT) {
28 		*IOP3XX_GPOE &= ~(1 << line);
29 	}
30 	local_irq_restore(flags);
31 }
32 EXPORT_SYMBOL(gpio_line_config);
33 
gpio_line_get(int line)34 int gpio_line_get(int line)
35 {
36 	return !!(*IOP3XX_GPID & (1 << line));
37 }
38 EXPORT_SYMBOL(gpio_line_get);
39 
gpio_line_set(int line,int value)40 void gpio_line_set(int line, int value)
41 {
42 	unsigned long flags;
43 
44 	local_irq_save(flags);
45 	if (value == GPIO_LOW) {
46 		*IOP3XX_GPOD &= ~(1 << line);
47 	} else if (value == GPIO_HIGH) {
48 		*IOP3XX_GPOD |= 1 << line;
49 	}
50 	local_irq_restore(flags);
51 }
52 EXPORT_SYMBOL(gpio_line_set);
53 
iop3xx_gpio_direction_input(struct gpio_chip * chip,unsigned gpio)54 static int iop3xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
55 {
56 	gpio_line_config(gpio, GPIO_IN);
57 	return 0;
58 }
59 
iop3xx_gpio_direction_output(struct gpio_chip * chip,unsigned gpio,int level)60 static int iop3xx_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int level)
61 {
62 	gpio_line_set(gpio, level);
63 	gpio_line_config(gpio, GPIO_OUT);
64 	return 0;
65 }
66 
iop3xx_gpio_get_value(struct gpio_chip * chip,unsigned gpio)67 static int iop3xx_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
68 {
69 	return gpio_line_get(gpio);
70 }
71 
iop3xx_gpio_set_value(struct gpio_chip * chip,unsigned gpio,int value)72 static void iop3xx_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
73 {
74 	gpio_line_set(gpio, value);
75 }
76 
77 static struct gpio_chip iop3xx_chip = {
78 	.label			= "iop3xx",
79 	.direction_input	= iop3xx_gpio_direction_input,
80 	.get			= iop3xx_gpio_get_value,
81 	.direction_output	= iop3xx_gpio_direction_output,
82 	.set			= iop3xx_gpio_set_value,
83 	.base			= 0,
84 	.ngpio			= IOP3XX_N_GPIOS,
85 };
86 
iop3xx_gpio_setup(void)87 static int __init iop3xx_gpio_setup(void)
88 {
89 	return gpiochip_add(&iop3xx_chip);
90 }
91 arch_initcall(iop3xx_gpio_setup);
92