Alexey T, Bitbuck Issue 73:

Lower part of STM32 CAN driver arch/arm/src/stm32/stm32_can.c uses all three hw tx mailboxes and clears TXFP bit in the CAN_MCR register (it means transmission order is defined by identifier and mailbox number).

This creates situation when order frames are put in upper part of CAN driver (via can_write) and order frames are sent on bus can be different (and I experience this in wild).

Since CAN driver API pretends to be "file like" I expect data to be read from fd the same order it is written. So I consider described behaviour to be a bug.

I propose either to set TXFP bit in the CAN_MCR register (FIFO transmit order) or to use only one mailbox.