On 22.12.2025 16:51:07, Ondrej Ille wrote:

yes, your thinking is correct, there is a bug there.

This was pointed to by another user right in the CTU CAN FD repository
where the Linux driver also lives:
https://github.com/Blebowski/CTU-CAN-FD/pull/2

It is as you say, it should be:

-- ssp_cfg |= FIELD_PREP(REG_TRV_DELAY_SSP_SRC, 0x1);
++ ssp_cfg |= FIELD_PREP(REG_TRV_DELAY_SSP_SRC, 0x0);

This statement has no effect, as 'ssp_cfg |= 0x0' is still 'ssp_cfg'.
IMHO it's better to add a comment that says, why you don't set
REG_TRV_DELAY_SSP_SRC. Another option is to add create a define that
replaces 0x1 and 0x0 for REG_TRV_DELAY_SSP_SRC with a speaking name.

regards,
Marc

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