1// Copyright 2017 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include <ddk/binding.h>
6#include <ddk/device.h>
7#include <ddk/driver.h>
8
9#include <zircon/types.h>
10#include <stdio.h>
11#include <stdlib.h>
12#include <string.h>
13
14static zx_status_t zero_read(void* ctx, void* buf, size_t count, zx_off_t off, size_t* actual) {
15    memset(buf, 0, count);
16    *actual = count;
17    return ZX_OK;
18}
19
20static zx_status_t zero_write(void* ctx, const void* buf, size_t count, zx_off_t off,
21                              size_t* actual) {
22    return ZX_ERR_NOT_SUPPORTED;
23}
24
25static zx_protocol_device_t zero_device_proto = {
26    .version = DEVICE_OPS_VERSION,
27    .read = zero_read,
28    .write = zero_write,
29};
30
31zx_status_t zero_bind(void* ctx, zx_device_t* parent, void** cookie) {
32    device_add_args_t args = {
33        .version = DEVICE_ADD_ARGS_VERSION,
34        .name = "zero",
35        .ops = &zero_device_proto,
36    };
37
38    zx_device_t* dev;
39    return device_add(parent, &args, &dev);
40}
41