DT: Add binding for Altera FPGAs in passive-serial mode
Altera FPGAs that are programmed via SPI use the passive serial protocol.
Add a simple binding that describes the setup for this usecase.
Cc: devicetree@vger.kernel.org
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>