I am designing a custom carrier board for Verdin iMX8M Plus, and new to this hardware platform.
HDMI interface is not used in the design of this carrier board.
Can HDMI-I2C (I2C5) and HDMIHPD/HDMICEC (I2C6) be used as general purpose I2C buses?
"The NXP i.MX 8M Plus SoC features six I2C controllers, five of which can be used externally. They
implement the I2C V2.1 specification. The port I2C1 is used for the on-module PMIC, RTC,
EEPROM, Secure Element, and ADC and is therefore not available externally.
All five externally available I2C can be used for general-purpose applications. However, the Verdin
standard dedicates three of them for use with the MIPI CSI-2 camera input, the MIPI DSI display
output, and the HDMI output. These three interfaces are in the “Reserved” category. There is a
proper general-purpose I2C port in the “Always Compatible” category. The fifth I2C port is only
available as an alternate function of other pins. Therefore, this interface is not compatible with
other Verdin modules.
The Verdin I2C_3_HDMI port is dedicated to the HDMI interface. The SoC pins that are connected to these module edge pins have two compatible multiplexing options. There is a dedicated HDMI_DDC interface available, as well as a general-purpose I2C interface (I2C5 instance).
Depending on the HDMI driver, the dedicated HDMI_DDC or the general-purpose I2C is used. If
the dedicated HDMI_DDC is in use, the I2C5 port could be used on other module edge pins that
offer the I2C5 as an alternate function. However, this configuration is not compatible with other
Verdin modules."
Verdin iMX8M Plus datasheet. Chapter 5.9 I2C