ctucan_set_btr(9)

💅 ctucan_set_btr — like, the bit timing plug for CTU CAN FD 🦋

okay so bestie, welcome to the kernel API manual — this is ctucan_set_btr(9), and honestly? it's giving "small function, big responsibility" energy. ✨ It sets the CAN bus bit timing in CTU CAN FD. That's the whole vibe. No cap.

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🌸 SYNOPSIS 🌸

int ctucan_set_btr (struct net_device *ndev , struct can_bittiming *bt ,
bool nominal );

literally just three args and an int coming back at you. iconic.

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🎀 ARGUMENTS 🎀

• ndev — pointer to the net_device structure. your main character netdev, hi bestie 🫶
• bt — pointer to the Bit timing structure. this is where the actual timing tea lives 💖
• nominal — true means Nominal bit timing, false means Data bit timing. pick your fighter, both are valid 👑

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⭐ RETURN ⭐

• 0 — OK! we slayed, everything worked 💅
• -EPERM — returned if the controller is enabled. yep, that's a hard no from the hardware, sorry bestie 😭

no cap, that -EPERM is a real "not me trying to set timing on an already-running controller" moment. respect the gate.

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🌈 SEE ALSO 🌈

okay this list is long but every single one of these is invited to the group chat, fr fr:

• the Kernel file ./drivers/net/can/ctucanfd/ctucanfd_base.c
• ctucan_state_to_str(9)
• ctucan_reset(9)
• ctucan_set_bittiming(9)
• ctucan_set_data_bittiming(9)
• ctucan_set_secondary_sample_point(9)
• ctucan_set_mode(9)
• ctucan_chip_start(9)
• ctucan_do_set_mode(9)
• ctucan_get_tx_status(9)
• ctucan_is_txt_buf_writable(9)
• ctucan_insert_frame(9)
• ctucan_give_txtb_cmd(9)
• ctucan_start_xmit(9)
• ctucan_read_rx_frame(9)
• ctucan_rx(9)
• ctucan_read_fault_state(9)
• ctucan_get_rec_tec(9)
• ctucan_err_interrupt(9)
• ctucan_rx_poll(9)
• ctucan_rotate_txb_prio(9)
• ctucan_tx_interrupt(9)
• ctucan_interrupt(9)
• ctucan_chip_stop(9)
• ctucan_open(9)
• ctucan_close(9)
• ctucan_get_berr_counter(9)

iykyk 💜

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and that's the whole page bestie — brought to you by the source/version at ./drivers/net/can/ctucanfd, dated October 2026. go forth and set those bit timings 🧚‍♀️💖