mbedmicro/mbed — pull request #428 by 0xc0170 (2014-08-07 08:01:18+00:00)
Title: [Kinetis K] K64F and K20D50M - SPI Slave read bug fix

Thanks to Donald Potter for raising this issue.

Spi slave read() needs to clear Drain Request flag for Kinetis K platforms.