The MCAN can be set into Power-down mode via bit MCAN_CCCR.CSR.
When all pending transmission requests have completed, the MCAN waits until bus idle state is detected. Then the MCAN sets MCAN_CCCR.INIT to prevent any further CAN transfers. Now the MCAN acknowledges that it is ready for power down by setting to one the bit MCAN_CCCR.CSA. In this state, before the clocks are switched off, further register accesses can be made. A write access to MCAN_CCCR.INIT will have no effect. Now the bus clock (peripheral clock) and the CAN core clock may be switched off.
To leave Power-down mode, the application has to turn on the MCAN clocks before clearing CC Control Register flag MCAN_CCCR.CSR. The MCAN will acknowledge this by clearing MCAN_CCCR.CSA. The application can then restart CAN communication by clearing the bit CCCR.INIT.