Only the I2C is officially supported by i-TRiLOGI.
The SPI pins are available but not officially supported by i-TRiLOGI. For SmartTILE customers who need to design custom interface to external SPI devices special helps can be arranged with TRi tech support to enable the use of the SPI pins. Please write to support@triplc.com and provide some project details to initiate the design support.