ChibiOS/os/hal/include/io_block.h

269 lines
9.3 KiB
C

/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file io_block.h
* @brief I/O block devices access.
* @details This header defines abstract interfaces useful to access generic
* I/O block devices in a standardized way.
*
* @addtogroup IO_BLOCK
* @details This module define an abstract interface for accessing generic
* block devices.
* Note that no code is present, just abstract interfaces-like
* structures, you should look at the system as to a set of
* abstract C++ classes (even if written in C). This system
* has then advantage to make the access to block devices
* independent from the implementation logic.
* @{
*/
#ifndef _IO_BLOCK_H_
#define _IO_BLOCK_H_
/**
* @brief Driver state machine possible states.
*/
typedef enum {
BLK_UNINIT = 0, /**< Not initialized. */
BLK_STOP = 1, /**< Stopped. */
BLK_ACTIVE = 2, /**< Interface active. */
BLK_CONNECTING = 3, /**< Connection in progress. */
BLK_DISCONNECTING = 4, /**< Disconnection in progress. */
BLK_READY = 5, /**< Device ready. */
BLK_READING = 6, /**< Read operation in progress. */
BLK_WRITING = 7 /**< Write operation in progress. */
} blkstate_t;
/**
* @brief Block device info.
*/
typedef struct {
uint32_t blk_size; /**< @brief Block size in bytes. */
uint32_t blk_num; /**< @brief Total number of blocks. */
} BlockDeviceInfo;
/**
* @brief @p BaseBlockDevice specific methods.
*/
#define _base_block_device_methods \
/* Removable media detection.*/ \
bool_t (*is_inserted)(void *instance); \
/* Removable write protection detection.*/ \
bool_t (*is_protected)(void *instance); \
/* Connection to the block device.*/ \
bool_t (*connect)(void *instance); \
/* Disconnection from the block device.*/ \
bool_t (*disconnect)(void *instance); \
/* Reads one or more blocks.*/ \
bool_t (*read)(void *instance, uint32_t startblk, \
uint8_t *buffer, uint32_t n); \
/* Writes one or more blocks.*/ \
bool_t (*write)(void *instance, uint32_t startblk, \
const uint8_t *buffer, uint32_t n); \
/* Write operations synchronization.*/ \
bool_t (*sync)(void *instance); \
/* Obtains info about the media.*/ \
bool_t (*get_info)(void *instance, BlockDeviceInfo *bdip);
/**
* @brief @p BaseBlockDevice specific data.
*/
#define _base_block_device_data \
/* Driver state.*/ \
blkstate_t state;
/**
* @brief @p BaseBlockDevice virtual methods table.
*/
struct BaseBlockDeviceVMT {
_base_block_device_methods
};
/**
* @brief Base block device class.
* @details This class represents a generic, block-accessible, device.
*/
typedef struct {
/** @brief Virtual Methods Table.*/
const struct BaseBlockDeviceVMT *vmt;
_base_block_device_data
} BaseBlockDevice;
/**
* @name Macro Functions (BaseBlockDevice)
* @{
*/
/**
* @brief Returns the driver state.
* @note Can be called in ISR context.
*
* @param[in] ip pointer to a @p BaseBlockDevice or derived class
*
* @return The driver state.
*
* @special
*/
#define blkGetDriverState(ip) ((ip)->state)
/**
* @brief Determines if the device is transferring data.
* @note Can be called in ISR context.
*
* @param[in] ip pointer to a @p BaseBlockDevice or derived class
*
* @return The driver state.
* @retval FALSE the device is not transferring data.
* @retval TRUE the device not transferring data.
*
* @special
*/
#define blkIsTransferring(ip) ((((ip)->state) == BLK_CONNECTING) || \
(((ip)->state) == BLK_DISCONNECTING) || \
(((ip)->state) == BLK_READING) || \
(((ip)->state) == BLK_WRITING))
/**
* @brief Returns the media insertion status.
* @note On some implementations this function can only be called if the
* device is not transferring data.
* The function @p blkIsTransferring() should be used before calling
* this function.
*
* @param[in] ip pointer to a @p BaseBlockDevice or derived class
*
* @return The media state.
* @retval FALSE media not inserted.
* @retval TRUE media inserted.
*
* @api
*/
#define blkIsInserted(ip) ((ip)->vmt->is_inserted(ip))
/**
* @brief Returns the media write protection status.
*
* @param[in] ip pointer to a @p BaseBlockDevice or derived class
*
* @return The media state.
* @retval FALSE writable media.
* @retval TRUE non writable media.
*
* @api
*/
#define blkIsWriteProtected(ip) ((ip)->vmt->is_protected(ip))
/**
* @brief Performs the initialization procedure on the block device.
* @details This function should be performed before I/O operations can be
* attempted on the block device and after insertion has been
* confirmed using @p blkIsInserted().
*
* @param[in] ip pointer to a @p BaseBlockDevice or derived class
*
* @return The operation status.
* @retval CH_SUCCESS operation succeeded.
* @retval CH_FAILED operation failed.
*
* @api
*/
#define blkConnect(ip) ((ip)->vmt->connect(ip))
/**
* @brief Terminates operations on the block device.
* @details This operation safely terminates operations on the block device.
*
* @param[in] ip pointer to a @p BaseBlockDevice or derived class
*
* @return The operation status.
* @retval CH_SUCCESS operation succeeded.
* @retval CH_FAILED operation failed.
*
* @api
*/
#define blkDisconnect(ip) ((ip)->vmt-disconnect(ip))
/**
* @brief Reads one or more blocks.
*
* @param[in] ip pointer to a @p BaseBlockDevice or derived class
* @param[in] startblk first block to read
* @param[out] buf pointer to the read buffer
* @param[in] n number of blocks to read
*
* @return The operation status.
* @retval CH_SUCCESS operation succeeded.
* @retval CH_FAILED operation failed.
*
* @api
*/
#define blkRead(ip, startblk, buf, n) \
((ip)->vmt->read(ip, startblk, buf, n))
/**
* @brief Writes one or more blocks.
*
* @param[in] ip pointer to a @p BaseBlockDevice or derived class
* @param[in] startblk first block to write
* @param[out] buf pointer to the write buffer
* @param[in] n number of blocks to write
*
* @return The operation status.
* @retval CH_SUCCESS operation succeeded.
* @retval CH_FAILED operation failed.
*
* @api
*/
#define blkWrite(ip, startblk, buf, n) \
((ip)->vmt->write(ip, startblk, buf, n))
/**
* @brief Ensures write synchronization.
*
* @param[in] ip pointer to a @p BaseBlockDevice or derived class
*
* @return The operation status.
* @retval CH_SUCCESS operation succeeded.
* @retval CH_FAILED operation failed.
*
* @api
*/
#define blkSync(ip) ((ip)->vmt->sync(ip))
/**
* @brief Returns a media information structure.
*
* @param[in] ip pointer to a @p BaseBlockDevice or derived class
* @param[out] bdip pointer to a @p BlockDeviceInfo structure
*
* @return The operation status.
* @retval CH_SUCCESS operation succeeded.
* @retval CH_FAILED operation failed.
*
* @api
*/
#define blkGetInfo(ip, bdip) ((ip)->vmt->get_info(ip, bdip))
/** @} */
#endif /* _IO_BLOCK_H_ */
/** @} */