LXR uboot/include/spl

   1/* SPDX-License-Identifier: GPL-2.0+ */
   2/*
   3 * Simple GPIO access from SPL. This only supports a single GPIO space,
   4 * typically the SoC GPIO banks.
   5 *
   6 * Copyright 2018 Google LLC
   7 */
   8
   9#ifndef __SPL_GPIO_H
  10#define __SPL_GPIO_H
  11
  12#include <asm/gpio.h>
  13
  14/*
  15 * The functions listed here should be implemented in the SoC GPIO driver.
  16 * They correspond to the normal GPIO API (asm-generic/gpio.h). The GPIO
  17 * number is encoded in an unsigned int by an SoC-specific means. Pull
  18 * values are also SoC-specific.
  19 *
  20 * This API should only be used in TPL/SPL where GPIO access is needed but
  21 * driver model is not available (yet) or adds too much overhead.
  22 *
  23 * The caller must supply the GPIO register base since this information is
  24 * often specific to a particular SoC generation. This allows the GPIO
  25 * code to be fairly generic.
  26 *
  27 * Only a single implementation of each of these functions can be provided.
  28 *
  29 * The 'gpio' value can include both a bank and a GPIO number, if desired. The
  30 * encoding is SoC-specific.
  31 */
  32
  33/**
  34 * spl_gpio_set_pull() - Set the pull up/down state of a GPIO
  35 *
  36 * @regs: Pointer to GPIO registers
  37 * @gpio: GPIO to adjust (SoC-specific)
  38 * @pull: Pull value (SoC-specific)
  39 * @return return 0 if OK, -ve on error
  40 */
  41int spl_gpio_set_pull(void *regs, uint gpio, int pull);
  42
  43/**
  44 * spl_gpio_output() - Set a GPIO as an output
  45 *
  46 * @regs: Pointer to GPIO registers
  47 * @gpio: GPIO to adjust (SoC-specific)
  48 * @value: 0 to set the output low, 1 to set it high
  49 * @return return 0 if OK, -ve on error
  50 */
  51int spl_gpio_output(void *regs, uint gpio, int value);
  52
  53/**
  54 * spl_gpio_input() - Set a GPIO as an input
  55 *
  56 * @regs: Pointer to GPIO registers
  57 * @gpio: GPIO to adjust (SoC-specific)
  58 * @return return 0 if OK, -ve on error
  59 */
  60int spl_gpio_input(void *regs, uint gpio);
  61
  62#endif /* __SPL_GPIO_H */
  63