include/drivers/io/io_driver.h

   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, ssize_t 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 */