1 /*
2  * Copyright (c) 2014, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #ifndef IO_DRIVER_H
8 #define IO_DRIVER_H
9 
10 #include <stdint.h>
11 
12 #include <drivers/io/io_storage.h>
13 
14 /* Generic IO entity structure,representing an accessible IO construct on the
15  * device, such as a file */
16 typedef struct io_entity {
17 	struct io_dev_info *dev_handle;
18 	uintptr_t info;
19 } io_entity_t;
20 
21 
22 /* Device info structure, providing device-specific functions and a means of
23  * adding driver-specific state */
24 typedef struct io_dev_info {
25 	const struct io_dev_funcs *funcs;
26 	uintptr_t info;
27 } io_dev_info_t;
28 
29 
30 /* Structure used to create a connection to a type of device */
31 typedef struct io_dev_connector {
32 	/* dev_open opens a connection to a particular device driver */
33 	int (*dev_open)(const uintptr_t dev_spec, io_dev_info_t **dev_info);
34 } io_dev_connector_t;
35 
36 
37 /* Structure to hold device driver function pointers */
38 typedef struct io_dev_funcs {
39 	io_type_t (*type)(void);
40 	int (*open)(io_dev_info_t *dev_info, const uintptr_t spec,
41 			io_entity_t *entity);
42 	int (*seek)(io_entity_t *entity, int mode, signed long long offset);
43 	int (*size)(io_entity_t *entity, size_t *length);
44 	int (*read)(io_entity_t *entity, uintptr_t buffer, size_t length,
45 			size_t *length_read);
46 	int (*write)(io_entity_t *entity, const uintptr_t buffer,
47 			size_t length, size_t *length_written);
48 	int (*close)(io_entity_t *entity);
49 	int (*dev_init)(io_dev_info_t *dev_info, const uintptr_t init_params);
50 	int (*dev_close)(io_dev_info_t *dev_info);
51 } io_dev_funcs_t;
52 
53 
54 /* Operations intended to be performed during platform initialisation */
55 
56 /* Register an IO device */
57 int io_register_device(const io_dev_info_t *dev_info);
58 
59 #endif /* IO_DRIVER_H */
60