Not a question, I just want to write this in hope that the next who
stumbles across the problem finds a solution in this post.
* If you wonder why each SPI transfer takes 4.7 milliseconds longer than
it should: Disable the 'Debug Support for SPI Devices' (SPI_DEBUG) in
the kernel.
The Omap SPI driver will print out the speed and bit settings each time
it sets up a transfer. If your syslog goes to the UART (very likely)
this will delay each SPI-transaction so much that it becomes unusable
for most applications.
Cheers,
Nils