xref: /linux/arch/sh/boards/mach-sdk7786/gpio.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * SDK7786 FPGA USRGPIR Support.
3  *
4  * Copyright (C) 2010  Paul Mundt
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 #include <linux/init.h>
11 #include <linux/interrupt.h>
12 #include <linux/gpio.h>
13 #include <linux/irq.h>
14 #include <linux/kernel.h>
15 #include <linux/spinlock.h>
16 #include <linux/io.h>
17 #include <mach/fpga.h>
18 
19 #define NR_FPGA_GPIOS	8
20 
21 static const char *usrgpir_gpio_names[NR_FPGA_GPIOS] = {
22 	"in0", "in1", "in2", "in3", "in4", "in5", "in6", "in7",
23 };
24 
25 static int usrgpir_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
26 {
27 	/* always in */
28 	return 0;
29 }
30 
31 static int usrgpir_gpio_get(struct gpio_chip *chip, unsigned gpio)
32 {
33 	return !!(fpga_read_reg(USRGPIR) & (1 << gpio));
34 }
35 
36 static struct gpio_chip usrgpir_gpio_chip = {
37 	.label			= "sdk7786-fpga",
38 	.names			= usrgpir_gpio_names,
39 	.direction_input	= usrgpir_gpio_direction_input,
40 	.get			= usrgpir_gpio_get,
41 	.base			= -1, /* don't care */
42 	.ngpio			= NR_FPGA_GPIOS,
43 };
44 
45 static int __init usrgpir_gpio_setup(void)
46 {
47 	return gpiochip_add(&usrgpir_gpio_chip);
48 }
49 device_initcall(usrgpir_gpio_setup);
50