This is an improved version of the driver patch original
submitted by Graeme Smecher <graeme.smecher@mail.mcgill.ca>
The changes are:
- remove hard coded Xilinx BSP defines (XPAR_SPI_*) and
use CONFIG_SYS_SPI_BASE from config.h instead
- add extensive register struct definitions
- remove offset calculation for register access and
use the new register struct instead
- move default SPI controller configuration from
spi_setup_slave() to spi_claim_bus()
- add spi_set_speed()
- insert SPI controller deactivation in spi_release_bus()
- protect while loops in spi_xfer() with counter / timeouts
- support SPI mode flags: LSB_FIRST, CPHA, CPOL, LOOP
Come from:
http://patchwork.ozlabs.org/patch/71797/
Signed-off-by: Stephan Linz <linz@li-pro.net>
Tested-by: Michal Simek <monstr@monstr.eu>
