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/*
* Copyright (c) 2014, ARM Limited and Contributors. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of ARM nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __IO_DRIVER_H__
#define __IO_DRIVER_H__
#include "platform.h" /* For MAX_IO_DEVICES */
/* Generic IO entity structure,representing an accessible IO construct on the
* device, such as a file */
struct io_entity {
io_dev_handle dev_handle;
uintptr_t info;
};
/* Device info structure, providing device-specific functions and a means of
* adding driver-specific state */
struct io_dev_info {
struct io_dev_funcs *funcs;
uintptr_t info;
};
/* Structure used to create a connection to a type of device */
struct io_dev_connector {
/* dev_open opens a connection to a particular device driver */
int (*dev_open)(void *spec, struct io_dev_info **dev_info);
};
/* Structure to hold device driver function pointers */
struct io_dev_funcs {
io_type (*type)(void);
int (*open)(struct io_dev_info *dev_info, const void *spec,
struct io_entity *entity);
int (*seek)(struct io_entity *entity, int mode, ssize_t offset);
int (*size)(struct io_entity *entity, size_t *length);
int (*read)(struct io_entity *entity, void *buffer, size_t length,
size_t *length_read);
int (*write)(struct io_entity *entity, const void *buffer,
size_t length, size_t *length_written);
int (*close)(struct io_entity *entity);
int (*dev_init)(struct io_dev_info *dev_info, const void *init_params);
int (*dev_close)(struct io_dev_info *dev_info);
};
/* IO platform data - used to track devices registered for a specific
* platform */
struct io_plat_data {
struct io_dev_info *devices[MAX_IO_DEVICES];
unsigned int dev_count;
};
/* Operations intended to be performed during platform initialisation */
/* Initialise the IO layer */
void io_init(struct io_plat_data *data);
/* Register a device driver */
int io_register_device(struct io_dev_info *dev_info);
#endif /* __IO_DRIVER_H__ */