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/*
* Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <assert.h>
#include <string.h>
#include <common/debug.h>
#include <drivers/io/io_driver.h>
#include <drivers/io/io_dummy.h>
#include <drivers/io/io_storage.h>
struct file_state {
int in_use;
size_t size;
};
static struct file_state current_file = {0};
/* Identify the device type as dummy */
static io_type_t device_type_dummy(void)
{
return IO_TYPE_DUMMY;
}
/* Dummy device functions */
static int dummy_dev_open(const uintptr_t dev_spec, io_dev_info_t **dev_info);
static int dummy_block_open(io_dev_info_t *dev_info, const uintptr_t spec,
io_entity_t *entity);
static int dummy_block_len(io_entity_t *entity, size_t *length);
static int dummy_block_read(io_entity_t *entity, uintptr_t buffer,
size_t length, size_t *length_read);
static int dummy_block_close(io_entity_t *entity);
static int dummy_dev_close(io_dev_info_t *dev_info);
static const io_dev_connector_t dummy_dev_connector = {
.dev_open = dummy_dev_open
};
static const io_dev_funcs_t dummy_dev_funcs = {
.type = device_type_dummy,
.open = dummy_block_open,
.seek = NULL,
.size = dummy_block_len,
.read = dummy_block_read,
.write = NULL,
.close = dummy_block_close,
.dev_init = NULL,
.dev_close = dummy_dev_close,
};
static const io_dev_info_t dummy_dev_info = {
.funcs = &dummy_dev_funcs,
.info = (uintptr_t)NULL
};
/* Open a connection to the dummy device */
static int dummy_dev_open(const uintptr_t dev_spec __attribute__((unused)),
io_dev_info_t **dev_info)
{
assert(dev_info != NULL);
*dev_info = (io_dev_info_t *)&dummy_dev_info;
return 0;
}
/* Close a connection to the dummy device */
static int dummy_dev_close(io_dev_info_t *dev_info)
{
return 0;
}
/* Open a file on the dummy device */
static int dummy_block_open(io_dev_info_t *dev_info, const uintptr_t spec,
io_entity_t *entity)
{
int result;
const io_block_spec_t *block_spec = (io_block_spec_t *)spec;
if (current_file.in_use == 0) {
assert(block_spec != NULL);
assert(entity != NULL);
current_file.in_use = 1;
current_file.size = block_spec->length;
entity->info = (uintptr_t)¤t_file;
result = 0;
} else {
WARN("A Dummy device is already active. Close first.\n");
result = -ENOMEM;
}
return result;
}
/* Return the size of a file on the dummy device */
static int dummy_block_len(io_entity_t *entity, size_t *length)
{
assert(entity != NULL);
assert(length != NULL);
*length = ((struct file_state *)entity->info)->size;
return 0;
}
/* Read data from a file on the dummy device */
static int dummy_block_read(io_entity_t *entity, uintptr_t buffer,
size_t length, size_t *length_read)
{
assert(length_read != NULL);
*length_read = length;
return 0;
}
/* Close a file on the dummy device */
static int dummy_block_close(io_entity_t *entity)
{
assert(entity != NULL);
entity->info = 0;
current_file.in_use = 0;
return 0;
}
/* Exported functions */
/* Register the dummy driver with the IO abstraction */
int register_io_dev_dummy(const io_dev_connector_t **dev_con)
{
int result;
assert(dev_con != NULL);
result = io_register_device(&dummy_dev_info);
if (result == 0)
*dev_con = &dummy_dev_connector;
return result;
}