forked from Minki/linux
47da88f366
The sdk7786 FPGA supports a number of user settable input switches that are otherwise unused. This wires up a dummy gpio chip for the switch bank to simply expose them to userspace. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
50 lines
1.2 KiB
C
50 lines
1.2 KiB
C
/*
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* SDK7786 FPGA USRGPIR Support.
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*
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* Copyright (C) 2010 Paul Mundt
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*/
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/gpio.h>
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#include <linux/irq.h>
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#include <linux/kernel.h>
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#include <linux/spinlock.h>
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#include <linux/io.h>
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#include <mach/fpga.h>
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#define NR_FPGA_GPIOS 8
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static const char *usrgpir_gpio_names[NR_FPGA_GPIOS] = {
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"in0", "in1", "in2", "in3", "in4", "in5", "in6", "in7",
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};
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static int usrgpir_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
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{
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/* always in */
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return 0;
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}
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static int usrgpir_gpio_get(struct gpio_chip *chip, unsigned gpio)
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{
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return !!(fpga_read_reg(USRGPIR) & (1 << gpio));
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}
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static struct gpio_chip usrgpir_gpio_chip = {
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.label = "sdk7786-fpga",
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.names = usrgpir_gpio_names,
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.direction_input = usrgpir_gpio_direction_input,
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.get = usrgpir_gpio_get,
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.base = -1, /* don't care */
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.ngpio = NR_FPGA_GPIOS,
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};
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static int __init usrgpir_gpio_setup(void)
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{
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return gpiochip_add(&usrgpir_gpio_chip);
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}
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device_initcall(usrgpir_gpio_setup);
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