arch/sh/boards/mach-sdk7786/gpio.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * SDK7786 FPGA USRGPIR Support.
   4  *
   5  * Copyright (C) 2010  Paul Mundt
   6  */
   7 #include <linux/init.h>
   8 #include <linux/interrupt.h>
   9 #include <linux/gpio/driver.h>
  10 #include <linux/irq.h>
  11 #include <linux/kernel.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/io.h>
  14 #include <mach/fpga.h>
  15
  16 #define NR_FPGA_GPIOS   8
  17
  18 static const char *usrgpir_gpio_names[NR_FPGA_GPIOS] = {
  19         "in0", "in1", "in2", "in3", "in4", "in5", "in6", "in7",
  20 };
  21
  22 static int usrgpir_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
  23 {
  24         /* always in */
  25         return 0;
  26 }
  27
  28 static int usrgpir_gpio_get(struct gpio_chip *chip, unsigned gpio)
  29 {
  30         return !!(fpga_read_reg(USRGPIR) & (1 << gpio));
  31 }
  32
  33 static struct gpio_chip usrgpir_gpio_chip = {
  34         .label                  = "sdk7786-fpga",
  35         .names                  = usrgpir_gpio_names,
  36         .direction_input        = usrgpir_gpio_direction_input,
  37         .get                    = usrgpir_gpio_get,
  38         .base                   = -1, /* don't care */
  39         .ngpio                  = NR_FPGA_GPIOS,
  40 };
  41
  42 static int __init usrgpir_gpio_setup(void)
  43 {
  44         return gpiochip_add_data(&usrgpir_gpio_chip, NULL);
  45 }
  46 device_initcall(usrgpir_gpio_setup);