File changed.
Preview size limit exceeded, changes collapsed.
Loading
Universal Serial Interface (USI) supports three types of serial interface such as Universal Asynchronous Receiver and Transmitter (UART), Serial Peripheral Interface (SPI), and Inter-Integrated Circuit (I2C). Each protocols can be working independently and configured as one of those using external configuration inputs. Exynos Auto v9 SoC support 12 USIs. When a USI uses two pins such as i2c and 3 wire uarts(RX/TX only), we can use remain two pins as i2c mode. So, we can define one USI node that includes serial/spi and hsi2c. usi_i2c nodes can be used only for i2c mode. We can have below combinations for one USI. 1) The usi node is used either 4 pin uart or 4 pin spi -> No usi_i2c can be used 2) The usi node is used 2 pin uart(RX/TX) and i2c(SDA/SCL) -> usi_i2c should be enabled to use the latter i2c 3) The usi node is used i2c(SDA/SCL) and i2c(SDA/SCL) -> usi_i2c should be enabled to use the latter i2c By default, all USIs are initially set to uart mode by below setting. samsung,mode = <USI_V2_UART>; You can change it either USI_V2_SPI or USI_V2_I2C. Signed-off-by:Chanho Park <chanho61.park@samsung.com> Signed-off-by:
Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Link: https://lore.kernel.org/r/20220701015226.32781-6-chanho61.park@samsung.com
File changed.
Preview size limit exceeded, changes collapsed.