ddf_frame.h

一个简单的小型操作系统

/*****************************************************************************
 * 
 * Module       : ddf_frame.h
 * Description  : Simple low level Device Driver Framework
 * OS           : SLOS 0.09
 * Platform     : e7t
 * History      : 
 *
 * 19th November 2001 Andrew N. Sloss
 * - implemented version DDF 0.01 from Chris Wright's 
 *   specification
 *
 * December 2nd 2001 Andrew N. Sloss
 * - added uid generator
 *
 *****************************************************************************/

/*****************************************************************************
 * IMPORT
 *****************************************************************************/

#include "../core/uid.h" /* UID generator ................... */

/*****************************************************************************
 * MACROS
 *****************************************************************************/

/* none... */

/*****************************************************************************
 * DATATYPES
 *****************************************************************************/

/* -- DATA_STR ----------------------------------------------------------------
 *
 * Description : for block transfer devices
 * Fields      : unsigned int size - size of the block
 *             : void *data - point to the block of data
 *
 */

typedef struct data {
  unsigned int size;
  void 	     *data;
} block_data_t;

/* -- DATA_STR ----------------------------------------------------------------
 *
 * Description : for block transfer devices
 * Fields      : unsigned int size - size of the block
 * 		     : void *data - point to the block of data
 *
 */

typedef struct device_tree {

  /* -----------------------------------------------------------
   * Field          : name
   * Description    : name of the device driver
   * Example        : "LED Driver"
   *
   */	

  char  name[12];
  
  /* -----------------------------------------------------------
   * Field          : driver_id
   * Description    : is a unique identifer for the driver
   * Example        : for LED driver
   *
   */

  UID driver_id;

  /* -----------------------------------------------------------
   * Field          : fn * init
   * Description    : initialize internel specific
   *	               : device driver functions
   * Example        : led_init ();
   * Returns        : none...
   */

  void 	(*init)   	(void);

  /* -----------------------------------------------------------
   * Field          : fn * open
   * Description    : opens a device for access
   * Example        : uid = open (SERIAL,COM1);
   * Returns        : UID
   *
   *	>0 - SUCCESS
   *	-1 - DEVICE_IN_USE
   * -2 - DEVICE_UNKNOWN
   *
   */

  UID	(*open)   	(unsigned int, unsigned int);

  /* -----------------------------------------------------------
   * Field          : fn * close
   * Description    : opens a device for access
   * Example        : uid = open (SERIAL,COM1);
   * Returns        : UID
   *
   *	 0 - DEVICE_SUCCESS
   *  -2 - DEVICE_UNKNOWN
   *
   */

  int	(*close)	(UID);

    /**********************************************************
     * WRITE
     **********************************************************/	

    union  
    {

    /* --------------------------------------------------------
     * Field        : fn * byte
     * Description  : write a byte to a particular device
     * Example      : write.byte (SEGMENT,SEVEN);
     * Returns      : none...
     *
     */

    void		(*byte)	 (UID, BYTE);

    /* --------------------------------------------------------
     * Field        : fn * bit
     * Description  : write a bit to a particular device
     * Example      : write.bit (LEDRED,REDON);
     * Returns      : none...
     *
     */

    void		(*bit)	 (UID, BYTE);

    /* --------------------------------------------------------
     * Field        : fn * bit
     * Description  : write a block to a particular device
     * Example      : write.block (ETHER,&PACKET);
     * Returns      : none...
     *
     */

    void		(*block) (UID, block_data_t *);

    } write;


    /**********************************************************
     * READ
     **********************************************************/	

    union 
    {

    /* --------------------------------------------------------
     * Field        : fn * byte
     * Description  : read a byte from a particular device
     * Example      : c = read.block (SERIAL,COM1);
     * Returns      : BYTE - 8-bit unsigned char
     *
     */

    BYTE 		(*byte)  (UID); 
    
    /* --------------------------------------------------------
     * Field        : fn * bit
     * Description  : read a bit from a particular device
     * Example      : is_redled_on = read.bit (LED_RED);
     * Returns      : BYTE - only least significant bit is 
     *                important  
     *
     */

    BYTE 		(*bit)   (UID);

    /* --------------------------------------------------------
     * Field        : fn * block
     * Description  : write a block to a particular device
     * Example      : recieved = write.block (ETHER);
     * Returns      : block_data_t 
     *
     */

    block_data_t 	*(*block) (UID);
    
    } read;

} device_treestr ;

extern device_treestr devices[];