arm64: dts: exynosautov9: add usi device tree nodes

arm64: dts: exynosautov9: add usi device tree nodes

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