gpio.c 1.1 KB

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  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. #define NR_FPGA_GPIOS 8
  16. static const char *usrgpir_gpio_names[NR_FPGA_GPIOS] = {
  17. "in0", "in1", "in2", "in3", "in4", "in5", "in6", "in7",
  18. };
  19. static int usrgpir_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
  20. {
  21. /* always in */
  22. return 0;
  23. }
  24. static int usrgpir_gpio_get(struct gpio_chip *chip, unsigned gpio)
  25. {
  26. return !!(fpga_read_reg(USRGPIR) & (1 << gpio));
  27. }
  28. static struct gpio_chip usrgpir_gpio_chip = {
  29. .label = "sdk7786-fpga",
  30. .names = usrgpir_gpio_names,
  31. .direction_input = usrgpir_gpio_direction_input,
  32. .get = usrgpir_gpio_get,
  33. .base = -1, /* don't care */
  34. .ngpio = NR_FPGA_GPIOS,
  35. };
  36. static int __init usrgpir_gpio_setup(void)
  37. {
  38. return gpiochip_add_data(&usrgpir_gpio_chip, NULL);
  39. }
  40. device_initcall(usrgpir_gpio_setup);