source: svn/trunk/newcon3bcm2_21bu/BSEAV/lib/scte65/nit/si_nit_cds.c

/***************************************************************
**
** Broadcom Corp. Confidential
** Copyright 2003-2008 Broadcom Corp. All Rights Reserved.
**
** 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.
**
** File:                si_nit_cds.c
** Description: function that parses the CDS subtable of the NIT
**              table section. 
**
** Created: 03/08/2001 
**
** REVISION:
**
** $Log: $
**
**
****************************************************************/

#include "si.h"
#include "si_os.h"
#include "si_dbg.h"
#include "si_util.h"
#include "si_nit_cds.h"

/* the carrier frequency table as defined by one or more CDS subtable in NIT */
/* later in SVCT, the CDS__reference should be the index for this table to find */
/* a particular carrier frequency for a Virtual channel. */
/* the frequency is described in KHz unit. */
unsigned long NIT_CDS_Freq_KHZ_Table[NIT_CDS_MAX_NUM_OF_CARRIRE_INDEX];
unsigned long Total_NIT_CDS_carriers = 0;
static SI_CDS_Callback_t *s_CDS_Callback = NULL;


void SI_NIT_CDS_Init (SI_CDS_Callback_t *cb)
{
        SI_memset(NIT_CDS_Freq_KHZ_Table, 0, sizeof(NIT_CDS_Freq_KHZ_Table));
        Total_NIT_CDS_carriers = 0;
        s_CDS_Callback = cb;
}

/*********************************************************************/
/* Function : SI_NIT_CDS_parse                                                                           */
/* Description : Function to parse the CDS subtable and populate the */
/*               carrier freq table.                                                             */
/* Input : cds_record, point to the current ith CDS subtable         */
/*            defined in NIT table section. There may be up to       */
/*            number_of_record CDS subtables defined in NIT table    */
/*            section. See table 5.1 of DVS234.                                          */
/*         idx, point to the carrier index where the carriers        */
/*                        defined in this CDS will be located.                                   */
/* Output : The number of carriers defined in this CDS. It can be    */
/*                      used to increment the first_index in the NIT table  to   */
/*                      be passed as idx of this function.                                               */
/*********************************************************************/
unsigned char SI_NIT_CDS_parse (unsigned char * cds_record, unsigned char idx)
{
        unsigned long num_of_carriers;
        unsigned long frequency_spacing;
        unsigned long first_carrier_frequency;
        unsigned long unit, unitnum;
        long    i;

        SI_DBG_PRINT(E_SI_DBG_MSG,("NIT CDS Table received.\n"));
        
        num_of_carriers = SI_Construct_Data(cds_record, 
                                                NIT_CDS_NUMBER_OF_CARRIERS_BYTE_INDX,
                                                NIT_CDS_NUMBER_OF_CARRIERS_BYTE_NUM,
                                                NIT_CDS_NUMBER_OF_CARRIERS_SHIFT,
                                                NIT_CDS_NUMBER_OF_CARRIERS_MASK);

        unit = SI_Construct_Data(cds_record, 
                        NIT_CDS_SPACING_UNIT_BYTE_INDX,
                        NIT_CDS_SPACING_UNIT_BYTE_NUM,
                        NIT_CDS_SPACING_UNIT_BYTE_SHIFT,
                        NIT_CDS_SPACING_UNIT_BYTE_MASK);
        unitnum = (unit?NIT_CDS_SPACING_UNIT1:NIT_CDS_SPACING_UNIT0);
        frequency_spacing = SI_Construct_Data(cds_record, 
                        NIT_CDS_FREQUENCY_SPACING_BYTE_INDX,
                        NIT_CDS_FREQUENCY_SPACING_BYTE_NUM,
                        NIT_CDS_FREQUENCY_SPACING_BYTE_SHIFT,
                        NIT_CDS_FREQUENCY_SPACING_BYTE_MASK);
        SI_DBG_PRINT(E_SI_DBG_MSG,("freq space %x, unit %d kHz, real space %d\n", frequency_spacing, unitnum, frequency_spacing*unitnum));              
        frequency_spacing *= unitnum;
        
        unit = SI_Construct_Data(cds_record, 
                        NIT_CDS_FREQUENCY_UNIT_BYTE_INDX,
                        NIT_CDS_FREQUENCY_UNIT_BYTE_NUM,
                        NIT_CDS_FREQUENCY_UNIT_BYTE_SHIFT,
                        NIT_CDS_FREQUENCY_UNIT_BYTE_MASK);
        unitnum = (unit?NIT_CDS_FREQUENCY_UNIT1:NIT_CDS_FREQUENCY_UNIT0);

        first_carrier_frequency = SI_Construct_Data(cds_record, 
                        NIT_CDS_FIRST_CARRIER_FREQUENCY_BYTE_INDX,
                        NIT_CDS_FIRST_CARRIER_FREQUENCY_BYTE_NUM,
                        NIT_CDS_FIRST_CARRIER_FREQUENCY_BYTE_SHIFT,
                        NIT_CDS_FIRST_CARRIER_FREQUENCY_BYTE_MASK);
        SI_DBG_PRINT(E_SI_DBG_MSG,("1st freq %x, unit %d kHz, real freq %d\n", first_carrier_frequency, unitnum, first_carrier_frequency*unitnum));             
        first_carrier_frequency *= unitnum;

        SI_DBG_PRINT(E_SI_DBG_MSG,("NIT CDS num of carriers %x, spacing %d kHz, first freq %d kHz.\n", num_of_carriers, frequency_spacing, first_carrier_frequency));
        SI_DBG_PRINT(E_SI_DBG_MSG,("NIT CDS Actual Freqs defined (from index %x):\n", idx));
        for (i=0; i<num_of_carriers; i++)
        {
                NIT_CDS_Freq_KHZ_Table[idx+i] = first_carrier_frequency + i*frequency_spacing;
                SI_DBG_PRINT(E_SI_DBG_MSG,("%d kHz, ", NIT_CDS_Freq_KHZ_Table[idx+i]));
                if (s_CDS_Callback && s_CDS_Callback->cb)
                        s_CDS_Callback->cb(NIT_CDS_Freq_KHZ_Table[idx+i], idx+i, s_CDS_Callback->data);
        }
        SI_DBG_PRINT(E_SI_DBG_MSG,("\n"));

        Total_NIT_CDS_carriers = num_of_carriers;
        return (unsigned char)num_of_carriers;
}