18c2ecf20Sopenharmony_ci* Liebherr's BK4 controller external SPI 28c2ecf20Sopenharmony_ci 38c2ecf20Sopenharmony_ciA device which handles data acquisition from compatible industrial 48c2ecf20Sopenharmony_ciperipherals. 58c2ecf20Sopenharmony_ciThe SPI is used for data and management purposes in both master and 68c2ecf20Sopenharmony_cislave modes. 78c2ecf20Sopenharmony_ci 88c2ecf20Sopenharmony_ciRequired properties: 98c2ecf20Sopenharmony_ci 108c2ecf20Sopenharmony_ci- compatible : Should be "lwn,bk4" 118c2ecf20Sopenharmony_ci 128c2ecf20Sopenharmony_ciRequired SPI properties: 138c2ecf20Sopenharmony_ci 148c2ecf20Sopenharmony_ci- reg : Should be address of the device chip select within 158c2ecf20Sopenharmony_ci the controller. 168c2ecf20Sopenharmony_ci 178c2ecf20Sopenharmony_ci- spi-max-frequency : Maximum SPI clocking speed of device in Hz, should be 188c2ecf20Sopenharmony_ci 30MHz at most for the Liebherr's BK4 external bus. 198c2ecf20Sopenharmony_ci 208c2ecf20Sopenharmony_ciExample: 218c2ecf20Sopenharmony_ci 228c2ecf20Sopenharmony_cispidev0: spi@0 { 238c2ecf20Sopenharmony_ci compatible = "lwn,bk4"; 248c2ecf20Sopenharmony_ci spi-max-frequency = <30000000>; 258c2ecf20Sopenharmony_ci reg = <0>; 268c2ecf20Sopenharmony_ci}; 27