The CAN-FD protocol allows the transmission and reception of data at a
higher bit rate than the nominal rate used in the arbitration phase when
the message's BRS bit is set.

The TDC mechanism is effective only during the data phase of FD frames
having BRS bit set. It has no effect either on non-FD frames, or on FD
frames transmitted at normal bit rate.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20190712075926.7357-7-qiangqing.zhang@nxp.comSigned-off-by: Marc Kleine-Budde <mkl@pengutronix.de>