source: svn/trunk/newcon3bcm2_21bu/magnum/basemodules/reg/breg_spi.h @ 2

/***************************************************************************
 *         Copyright (c) 2003-2011, Broadcom Corporation
 *         All Rights Reserved
 *         Confidential Property of Broadcom Corporation
 *
 *      THIS SOFTWARE MAY ONLY BE USED SUBJECT TO AN EXECUTED SOFTWARE LICENSE
 *      AGREEMENT  BETWEEN THE USER AND BROADCOM.  YOU HAVE NO RIGHT TO USE OR
 *      EXPLOIT THIS MATERIAL EXCEPT SUBJECT TO THE TERMS OF SUCH AN AGREEMENT.
 *
 * $brcm_Workfile: breg_spi.h $
 * $brcm_Revision: Hydra_Software_Devel/10 $
 * $brcm_Date: 1/11/11 7:01p $
 *
 * Module Description:
 *
 * Revision History:
 *
 * $brcm_Log: /magnum/basemodules/reg/breg_spi.h $
 * 
 * Hydra_Software_Devel/10   1/11/11 7:01p mbatchel
 * SW35230-2053, SW35230-2702: Integrate SPI isr support for DTV.
 * 
 * Hydra_Software_Devel/SW35230-2053/1   11/11/10 1:55p mbatchel
 * SW35230-2053: Integrate SPI isr support for DTV.
 * 
 * Hydra_Software_Devel/9   1/13/04 5:02p brianlee
 * PR9268: Make write structures constant.
 * 
 * Hydra_Software_Devel/8   9/11/03 5:06p brianlee
 * Fixed SPI register interface function definitions.
 * 
 * Hydra_Software_Devel/7   9/11/03 10:51a brianlee
 * Fixed BREG_SPI_Read definition.
 * 
 * Hydra_Software_Devel/6   8/29/03 10:30a marcusk
 * Fixed BREG_SPI_Read definition.
 * 
 * Hydra_Software_Devel/5   8/22/03 2:52p marcusk
 * Updated with latest changes discussed in the UPG design review.
 * 
 * Hydra_Software_Devel/4   3/31/03 1:20p marcusk
 * Updated with comments on threadsafety
 * 
 * Hydra_Software_Devel/3   3/31/03 10:32a marcusk
 * Updated comments.
 * 
 * Hydra_Software_Devel/2   3/10/03 2:39p marcusk
 * Removed const keyword from read routines (copy paste error).
 * 
 * Hydra_Software_Devel/1   3/5/03 5:13p marcusk
 * Initial version.
 * 
 ***************************************************************************/

/*= Module Overview ********************************************************
This module provides a standard abstraction API for accessing SPI registers.
Several SPI busses may exist on a single platform. Some may be hardware based, 
while others software based (using GPIO pins). In order to hide the 
specific implementation of the SPI bus from a PortingInterface this SPI
register access abstraction is used.

---++++ SPI Register Handles
Hardware and software SPI implementations must follow the defined function 
prototype definitions. All SPI PortingInterfaces supply the a function 
that initializes a standard BREG_SPI_Handle (and fills it with function 
pointers provided by the specific SPI PortingInterfaces implementation).
Please refer to the specific SPI PortingInterface implementations for more
details.

An example of this type of function would be:

<verbatim>
BERR_Code BSPI_CreateSpiRegHandle( BSPI_Handle SpiHandle, BREG_SPI_Handle *pSpiRegHandle );
</verbatim>

This handle should be created during initialization and passed to the 
appropriate porting interfaces.  The porting interfaces in turn pass 
this handle to the abstract SPI functions when then call the appropriate 
SPI implementation though function pointers contained in the BREG_SPI_Handle.

---++++ Handling ThreadSafe with SPI
Since multiple modules (PortingInterface and otherwise) may be sharing the
same SPI bus, any function calls to the modules in question must be serialized
to prevent thread collisions.

        1 All calls to the modules sharing the same SPI handle must be protected
          through the use of a mutex.  This protection must be handled by the
          upper level software (driver, middleware, etc).
        2 Upper level software can create an additional layer between the SPI
          RegisterInterface and the corresponding SPI PortingInterface instance
          that implements the SPI register access.  In this layer a mutex is
          used to protect all SPI accesses.  This could easily be done
          using the BREG_SPI_Impl structure.
***************************************************************************/

#ifndef BREG_SPI_H
#define BREG_SPI_H

#ifdef __cplusplus
extern "C" {
#endif

/*
Summary:
This is an opaque handle that is used for SPI read and write functions.
*/
typedef struct BREG_SPI_Impl *BREG_SPI_Handle;

/*
Summary:
This function writes a programmable number of SPI registers.
*/
BERR_Code BREG_SPI_Write(
                                        BREG_SPI_Handle spiHandle,              /* Device channel handle */
                                        const uint8_t *pWriteData,              /* pointer to write memory location */
                                        size_t length                                   /* size of *pWriteData  buffers (number of bytes to write ) */
                                        );

/*
Summary:
This function reads a programmable number of SPI registers.

The SPI protocol always writes data out as it is reading data in.
The incoming data is stored in pReadData while the data
going out is sourced from pWriteData.
*/
BERR_Code BREG_SPI_Read(
                                        BREG_SPI_Handle spiHandle,              /* Device channel handle */
                                        const uint8_t *pWriteData,              /* pointer to memory location where data is to sent  */
                                        uint8_t *pReadData,             /* pointer to memory location to store read data  */
                                        size_t length                                   /* size of *pWriteData and *pReadData buffers (number of bytes to read + number of bytes to write) */
                                        );

/*
Summary:
This function writes a programmable number of SPI registers in isr.
*/
BERR_Code BREG_SPI_Write_isr(
                                        BREG_SPI_Handle spiHandle,              /* Device channel handle */
                                        const uint8_t *pWriteData,              /* pointer to write memory location */
                                        size_t length                                   /* size of *pWriteData  buffers (number of bytes to write ) */
                                        );

/*
Summary:
This function reads a programmable number of SPI registers in isr.

The SPI protocol always writes data out as it is reading data in.
The incoming data is stored in pReadData while the data
going out is sourced from pWriteData.
*/
BERR_Code BREG_SPI_Read_isr(
                                        BREG_SPI_Handle spiHandle,              /* Device channel handle */
                                        const uint8_t *pWriteData,              /* pointer to memory location where data is to sent  */
                                        uint8_t *pReadData,             /* pointer to memory location to store read data  */
                                        size_t length                                   /* size of *pWriteData and *pReadData buffers (number of bytes to read + number of bytes to write) */
                                        );


#ifdef __cplusplus
}
#endif
 
#endif
/* End of File */