How to get detailed document of OMAPL137

Hi, there

I used OMPA-L137 EVM board

http://www.ti.com/product/omap-l137?247SEM

I'm confused by below codes.  How to get those API reference/document? 

Please help me!  Thx!

/* Configure AIC3106 */
EVMOMAPL137_AIC3106_rset( AIC3106_PAGESELECT, 0 ); // Select page 0
EVMOMAPL137_AIC3106_rset( AIC3106_RESET, 0x80 ); // Reset AIC3106

EVMOMAPL137_AIC3106_rset( 3, 0x22 ); // 5 PLL A <- [PLL=OFF][Q=4][P=2]
EVMOMAPL137_AIC3106_rset( 4, 0x20 ); // 4 PLL B <- [J=8]
EVMOMAPL137_AIC3106_rset( 5, 0x6E ); // 5 PLL C <- [D=7075]

while ( ! ( MCASP1_SRCTL0 & 0x20 ) );
sample_data = MCASP1_RBUF0_32BIT;