Hi I am also having the similar issue for Flexcomm5 not able to assign PIN 0_7 and Pin 0_8 for I2C which has the following warning. Can help on this as well?
Issue: Signal I2C serial clock of the peripheral FLEXCOMM5 is not routed.
Level: Warning
Type: Validation
Tool: Pins
Origin: Peripherals:BOARD_InitPeripherals
Target: Pins: BOARD_InitPins
Resource: FLEXCOMM5.i2c_scl
Pin No.: 6, PIO0_7/FC3_RTS_SCL_SSEL1/SD0_CLK/FC5_SCK/FC1_SCK/SECURE_GPIO0_7
General purpose IO Port 0 pin 7;FLEXCOMM3 Request To Send output for the USART, SCL input/output for the I2C, Slave Select 1 input or output for the SPI; depends on the selected function.;SD/SDIO/MMC clock;FLEXCOMM5 Clock input or output for the USART function in synchronous modes, for the SPI function, for the I2S function (if present).;FLEXCOMM1 Clock input or output for the USART function in synchronous modes, for the SPI function, for the I2S function (if present).;Secure general purpose IO Port 0 pin 7
Pin No.: 26, PIO0_8/FC3_SSEL3/SD0_CMD/FC5_RXD_SDA_MOSI_DATA/SWO/SECURE_GPIO0_8
General purpose IO Port 0 pin 8;FLEXCOMM3 Slave Select 3 input or output for the SPI function.;Command input/output;FLEXCOMM5 Receive data input for the USART, SDA input/output for the I2C, Master data output/slave data input for the SPI, Data input or output for the I2S; depends on the selected function.;Serial wire output;Secure general purpose IO Port 0 pin 8
