can: ifi: Add obscure bit swap for EFF frame IDs
In case of CAN2.0 EFF frame, the controller handles frame IDs in a rather bizzare way. The ID is split into an extended part, IDX[28:11] and standard part, ID[10:0]. In the TX path, the core first sends the top 11 bits of the IDX, followed by ID and finally the rest of IDX. In the RX path, the core stores the ID the LSbit part of IDX field, followed by the LSbit parts of real IDX. The MSbit parts of IDX are stored in ID field of the register. This patch implements the necessary bit shuffling to mitigate this obscure behavior. In case two of these controllers are connected together, the RX and TX bit swapping nullifies itself and the issue does not manifest. The issue only manifests when talking to another different CAN controller. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Marc Kleine-Budde <mkl@pengutronix.de> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Oliver Hartkopp <socketcan@hartkopp.net> Cc: Wolfgang Grandegger <wg@grandegger.com> Reviewed-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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