1 /*
2 * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7 #include <assert.h>
8 #include <debug.h>
9 #include <io_driver.h>
10 #include <io_dummy.h>
11 #include <io_storage.h>
12 #include <string.h>
13
14 struct file_state {
15 int in_use;
16 size_t size;
17 };
18
19 static struct file_state current_file = {0};
20
21 /* Identify the device type as dummy */
device_type_dummy(void)22 static io_type_t device_type_dummy(void)
23 {
24 return IO_TYPE_DUMMY;
25 }
26
27 /* Dummy device functions */
28 static int dummy_dev_open(const uintptr_t dev_spec, io_dev_info_t **dev_info);
29 static int dummy_block_open(io_dev_info_t *dev_info, const uintptr_t spec,
30 io_entity_t *entity);
31 static int dummy_block_len(io_entity_t *entity, size_t *length);
32 static int dummy_block_read(io_entity_t *entity, uintptr_t buffer,
33 size_t length, size_t *length_read);
34 static int dummy_block_close(io_entity_t *entity);
35 static int dummy_dev_close(io_dev_info_t *dev_info);
36
37
38 static const io_dev_connector_t dummy_dev_connector = {
39 .dev_open = dummy_dev_open
40 };
41
42
43 static const io_dev_funcs_t dummy_dev_funcs = {
44 .type = device_type_dummy,
45 .open = dummy_block_open,
46 .seek = NULL,
47 .size = dummy_block_len,
48 .read = dummy_block_read,
49 .write = NULL,
50 .close = dummy_block_close,
51 .dev_init = NULL,
52 .dev_close = dummy_dev_close,
53 };
54
55
56 static const io_dev_info_t dummy_dev_info = {
57 .funcs = &dummy_dev_funcs,
58 .info = (uintptr_t)NULL
59 };
60
61
62 /* Open a connection to the dummy device */
dummy_dev_open(const uintptr_t dev_spec,io_dev_info_t ** dev_info)63 static int dummy_dev_open(const uintptr_t dev_spec __attribute__((unused)),
64 io_dev_info_t **dev_info)
65 {
66 assert(dev_info != NULL);
67 *dev_info = (io_dev_info_t *)&dummy_dev_info;
68
69 return 0;
70 }
71
72
73 /* Close a connection to the dummy device */
dummy_dev_close(io_dev_info_t * dev_info)74 static int dummy_dev_close(io_dev_info_t *dev_info)
75 {
76 return 0;
77 }
78
79
80 /* Open a file on the dummy device */
dummy_block_open(io_dev_info_t * dev_info,const uintptr_t spec,io_entity_t * entity)81 static int dummy_block_open(io_dev_info_t *dev_info, const uintptr_t spec,
82 io_entity_t *entity)
83 {
84 int result;
85 const io_block_spec_t *block_spec = (io_block_spec_t *)spec;
86
87 if (current_file.in_use == 0) {
88 assert(block_spec != NULL);
89 assert(entity != NULL);
90
91 current_file.in_use = 1;
92 current_file.size = block_spec->length;
93 entity->info = (uintptr_t)¤t_file;
94 result = 0;
95 } else {
96 WARN("A Dummy device is already active. Close first.\n");
97 result = -ENOMEM;
98 }
99
100 return result;
101 }
102
103
104 /* Return the size of a file on the dummy device */
dummy_block_len(io_entity_t * entity,size_t * length)105 static int dummy_block_len(io_entity_t *entity, size_t *length)
106 {
107 assert(entity != NULL);
108 assert(length != NULL);
109
110 *length = ((struct file_state *)entity->info)->size;
111
112 return 0;
113 }
114
115
116 /* Read data from a file on the dummy device */
dummy_block_read(io_entity_t * entity,uintptr_t buffer,size_t length,size_t * length_read)117 static int dummy_block_read(io_entity_t *entity, uintptr_t buffer,
118 size_t length, size_t *length_read)
119 {
120 assert(length_read != NULL);
121
122 *length_read = length;
123
124 return 0;
125 }
126
127
128 /* Close a file on the dummy device */
dummy_block_close(io_entity_t * entity)129 static int dummy_block_close(io_entity_t *entity)
130 {
131 assert(entity != NULL);
132
133 entity->info = 0;
134 current_file.in_use = 0;
135
136 return 0;
137 }
138
139
140 /* Exported functions */
141
142 /* Register the dummy driver with the IO abstraction */
register_io_dev_dummy(const io_dev_connector_t ** dev_con)143 int register_io_dev_dummy(const io_dev_connector_t **dev_con)
144 {
145 int result;
146
147 assert(dev_con != NULL);
148
149 result = io_register_device(&dummy_dev_info);
150 if (result == 0)
151 *dev_con = &dummy_dev_connector;
152
153 return result;
154 }
155