system/ulib/ddk/include/ddk/protocol/gpio-impl.h

// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#pragma once

#include <ddk/protocol/gpio.h>
#include <zircon/compiler.h>
#include <zircon/types.h>

__BEGIN_CDECLS;

typedef struct {
    zx_status_t (*config_in)(void* ctx, uint32_t pin, uint32_t flags);
    zx_status_t (*config_out)(void* ctx, uint32_t pin, uint8_t initial_value);
    zx_status_t (*set_alt_function)(void* ctx, uint32_t pin, uint64_t function);
    zx_status_t (*read)(void* ctx, uint32_t pin, uint8_t* out_value);
    zx_status_t (*write)(void* ctx, uint32_t pin, uint8_t value);
    zx_status_t (*get_interrupt)(void* ctx, uint32_t pin, uint32_t flags, zx_handle_t* out_handle);
    zx_status_t (*release_interrupt)(void* ctx, uint32_t pin);
    zx_status_t (*set_polarity)(void* ctx, uint32_t pin, uint32_t polarity);
} gpio_impl_protocol_ops_t;

typedef struct {
    gpio_impl_protocol_ops_t* ops;
    void* ctx;
} gpio_impl_protocol_t;

// configures a GPIO for input
static inline zx_status_t gpio_impl_config_in(const gpio_impl_protocol_t* gpio, uint32_t pin,
                                              uint32_t flags) {
    return gpio->ops->config_in(gpio->ctx, pin, flags);
}

// configures a GPIO for output
static inline zx_status_t gpio_impl_config_out(const gpio_impl_protocol_t* gpio, uint32_t pin,
                                               uint8_t initial_value) {
    return gpio->ops->config_out(gpio->ctx, pin, initial_value);
}

// configures the GPIO pin for an alternate function (I2C, SPI, etc)
// the interpretation of "function" is platform dependent
static inline zx_status_t gpio_impl_set_alt_function(const gpio_impl_protocol_t* gpio, uint32_t pin,
                                                     uint64_t function) {
    return gpio->ops->set_alt_function(gpio->ctx, pin, function);
}

// reads the current value of a GPIO (0 or 1)
static inline zx_status_t gpio_impl_read(const gpio_impl_protocol_t* gpio, uint32_t pin,
                                         uint8_t* out_value) {
    return gpio->ops->read(gpio->ctx, pin, out_value);
}

// sets the current value of the GPIO (any non-zero value maps to 1)
static inline zx_status_t gpio_impl_write(const gpio_impl_protocol_t* gpio, uint32_t pin,
                                          uint8_t value) {
    return gpio->ops->write(gpio->ctx, pin, value);
}

// gets an interrupt object pertaining to a particular GPIO pin
static inline zx_status_t gpio_impl_get_interrupt(const gpio_impl_protocol_t* gpio, uint32_t pin,
                                                  uint32_t flags, zx_handle_t* out_handle) {
    return gpio->ops->get_interrupt(gpio->ctx, pin, flags, out_handle);
}

// release the interrupt
static inline zx_status_t gpio_impl_release_interrupt(const gpio_impl_protocol_t* gpio, uint32_t pin) {
    return gpio->ops->release_interrupt(gpio->ctx, pin);
}

// Set GPIO polarity
static inline zx_status_t gpio_impl_set_polarity(const gpio_impl_protocol_t* gpio, uint32_t pin,
                                                 uint32_t polarity) {
    return gpio->ops->set_polarity(gpio->ctx, pin, polarity);
}
__END_CDECLS;